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Sample records for heavy chain mhc

  1. Signal peptide-dependent inhibition of MHC class I heavy chain translation by rhesus cytomegalovirus.

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    Colin J Powers

    2008-10-01

    Full Text Available The US2-11 region of human and rhesus cytomegalovirus encodes a conserved family of glycoproteins that inhibit MHC-I assembly with viral peptides, thus preventing cytotoxic T cell recognition. Since HCMV lacking US2-11 is no longer able to block assembly and transport of MHC-I, we examined whether this is also observed for RhCMV lacking the corresponding region. Unexpectedly, recombinant RhCMV lacking US2-11 was still able to inhibit MHC-I expression in infected fibroblasts, suggesting the presence of an additional MHC-I evasion mechanism. Progressive deletion analysis of RhCMV-specific genomic regions revealed that MHC-I expression is fully restored upon additional deletion of rh178. The protein encoded by this RhCMV-specific open reading frame is anchored in the endoplasmic reticulum membrane. In the presence of rh178, RhCMV prevented MHC-I heavy chain (HC expression, but did not inhibit mRNA transcription or association of HC mRNA with translating ribosomes. Proteasome inhibitors stabilized a HC degradation intermediate in the absence of rh178, but not in its presence, suggesting that rh178 prevents completion of HC translation. This interference was signal sequence-dependent since replacing the signal peptide with that of CD4 or murine HC rendered human HCs resistant to rh178. We have identified an inhibitor of antigen presentation encoded by rhesus cytomegalovirus unique in both its lack of homology to any other known protein and in its mechanism of action. By preventing signal sequence-dependent HC translocation, rh178 acts prior to US2, US3 and US11 which attack MHC-I proteins after protein synthesis is completed. Rh178 is the first viral protein known to interfere at this step of the MHC-I pathway, thus taking advantage of the conserved nature of HC leader peptides, and represents a new mechanism of translational interference.

  2. The C-terminal amino acid of the MHC-I heavy chain is critical for binding to Derlin-1 in human cytomegalovirus US11-induced MHC-I degradation.

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    Cho, Sunglim; Kim, Bo Young; Ahn, Kwangseog; Jun, Youngsoo

    2013-01-01

    Derlin-1 plays a critical role in endoplasmic reticulum-associated protein degradation (ERAD) of a particular subset of proteins. Although it is generally accepted that Derlin-1 mediates the export of ERAD substrates from the ER to the cytosol, little is known about how Derlin-1 interacts with these substrates. Human cytomegalovirus (HCMV) US11 exploits Derlin-1-dependent ERAD to degrade major histocompatibility complex class I (MHC-I) molecules and evade immune surveillance. US11 requires the cytosolic tail of the MHC-I heavy chain to divert MHC-I molecules into the ERAD pathway for degradation; however, the underlying mechanisms remain unknown. Here, we show that the cytosolic tail of the MHC-I heavy chain, although not required for interaction with US11, is required for tight binding to Derlin-1 and thus for US11-induced dislocation of the MHC-I heavy chain to the cytosol for proteasomal degradation. Surprisingly, deletion of a single C-terminal amino acid from the cytosolic tail disrupted the interaction between MHC-I molecules and Derlin-1, rendering mutant MHC-I molecules resistant to US11-induced degradation. Consistently, deleting the C-terminal cytosolic region of Derlin-1 prevented it from binding to MHC-I molecules. Taken together, these results suggest that the cytosolic region of Derlin-1 is involved in ERAD substrate binding and that this interaction is critical for the Derlin-1-mediated dislocation of the MHC-I heavy chain to the cytosol during US11-induced MHC-I degradation.

  3. Modified human beta 2-microglobulin (desLys(58)) displays decreased affinity for the heavy chain of MHC class I and induces nitric oxide production and apoptosis

    DEFF Research Database (Denmark)

    Wang, M; Harhaji, L; Lamberth, K

    2009-01-01

    Beta2-microglobulin (beta2m) is the light chain of major histocompatibility complex class I (MHC-I) molecules, and is a prerequisite for the binding of peptides to the heavy chain and their presentation to CD8+ T cells. beta2m can be modified in vivo and in vitro by proteolytic cleavage...... by complement C1 and subsequent carboxypeptidase B-like activity--processes that lead to the generation of desLys(58) beta2m (dbeta2m). This work aims to study the effect of dbeta2m on peptide binding to MHC-I, the influence of dbeta2m on the binding of beta2m to the MHC-I heavy chain and the biological...... activity of dbeta2m. Both beta2m and dbeta2m are able to support the generation of MHC-I/peptide complexes at 18 degrees C, but complexes formed in the presence of dbeta2m destabilize at 37 degrees C. Moreover, a 250 times higher concentration of dbeta2m than of beta2m is needed to displace MHC...

  4. Purification of correctly oxidized MHC class I heavy-chain molecules under denaturing conditions: a novel strategy exploiting disulfide assisted protein folding

    DEFF Research Database (Denmark)

    Ferré, Henrik; Ruffet, Emmanuel; Blicher, Thomas

    2003-01-01

    The aim of this study has been to develop a strategy for purifying correctly oxidized denatured major histocompability complex class I (MHC-I) heavy-chain molecules, which on dilution, fold efficiently and become functional. Expression of heavy-chain molecules in bacteria results in the formation...... of insoluble cellular inclusion bodies, which must be solubilized under denaturing conditions. Their subsequent purification and refolding is complicated by the fact that (1). correct folding can only take place in combined presence of beta(2)-microglobulin and a binding peptide; and (2). optimal in vitro...... conditions for disulfide bond formation ( approximately pH 8) and peptide binding ( approximately pH 6.6) are far from complementary. Here we present a two-step strategy, which relies on uncoupling the events of disulfide bond formation and peptide binding. In the first phase, heavy-chain molecules...

  5. Purification of correctly oxidized MHC class I heavy-chain molecules under denaturing conditions: A novel strategy exploiting disulfide assisted protein folding

    DEFF Research Database (Denmark)

    Ferré, Henrik; Ruffet, E.; Blicher, T.

    2003-01-01

    The aim of this study has been to develop a strategy for purifying correctly oxidized denatured major histocompability complex class I (MHC-I) heavy-chain molecules, which on dilution, fold efficiently and become functional. Expression of heavy-chain molecules in bacteria results in the formation...... of insoluble cellular inclusion bodies, which must be solubilized under denaturing conditions. Their subsequent purification and refolding is complicated by the fact that (1) correct folding can only take place in combined presence of beta(2)-microglobulin and a binding peptide; and (2) optimal in vitro...... conditions for disulfide bond formation (similar topH 8) and peptide binding (similar topH 6.6) are far from complementary. Here we present a two-step strategy, which relies on uncoupling the events of disulfide bond formation and peptide binding. In the first phase, heavy-chain molecules with correct...

  6. Heavy Chain Diseases

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    ... of heavy chain produced: Alpha Gamma Mu Alpha Heavy Chain Disease Alpha heavy chain disease (IgA heavy ... the disease or lead to a remission. Gamma Heavy Chain Disease Gamma heavy chain disease (IgG heavy ...

  7. Binding of human beta 2-microglobulin to murine EL4 thymoma cells upregulates MHC class I heavy-chain epitopes, inhibits IL-2 secretion and induces resistance to killing by natural killer cells

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    Claësson, M H; Nissen, Mogens Holst

    1994-01-01

    line (ABLS-8), X63 B-lymphoma cells and YAC cells did not bind h beta 2m. In two of the T lymphomas, EL4 and BW5147, binding of h beta 2m led to an increase in major histocompatibility complex class I (MHC-I) heavy-chain epitope expression as measured by anti-H-2K/D antibody binding and FACS analysis....... EL4 cells which had bound h beta 2m decreased their rate of constitutive IL-2 secretion and became resistant to activated natural killer (NK) cell killing. The present data suggest the binding of h beta 2m to mouse T cells leads to conformational changes of MHC-I heavy chains which influence both...

  8. Expression and characterization of recombinant single-chain salmon class I MHC fused with beta2-microglobulin with biological activity

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    Zhao, Heng; Stet, René J M; Skjødt, Karsten

    2008-01-01

    Heterodimeric class I major histocompatibility complex (MHC) molecules consist of a putative 45-kDa heavy chain and a 12-kDa beta2-microglobulin (beta2m) light chain. The knowledge about MHC genes in Atlantic salmon accumulated during the last decade has allowed us to generate soluble and stable ...... MHC class I molecules with biological activity. We report here the use of a bacterial expression system to produce the recombinant single-chain MHC molecules based on a specific allele Sasa-UBA*0301. This particular allele was selected because previous work has shown its association...... antibodies were successfully produced against both the MHC class I heavy chain and beta(2)m, and showed binding to the recombinant molecule. The recombinant complex Sasabeta2mUBA*0301 was expressed and isolated; the production was scaled up by adjusting to its optimal conditions. Subsequently......, the recombinant proteins were purified by affinity chromatography using mAb against beta2m and alpha3. Eluates were analyzed by Western blot and refolded by the removal of denaturant. The correct folding was confirmed by measuring its binding capacity against mAb produced to recognize the native form of MHC...

  9. Heavy chain only antibodies

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    Moghimi, Seyed Moein; Rahbarizadeh, Fatemeh; Ahmadvand, Davoud

    2013-01-01

    Unlike conventional antibodies, heavy chain only antibodies derived from camel contain a single variable domain (VHH) and two constant domains (CH2 and CH3). Cloned and isolated VHHs possess unique properties that enable them to excel conventional therapeutic antibodies and their smaller antigen...

  10. Myosin heavy chain expression in rabbit masseter muscle during postnatal development

    NARCIS (Netherlands)

    Bredman, J. J.; Weijs, W. A.; Korfage, H. A.; Brugman, P.; Moorman, A. F.

    1992-01-01

    The expression of isoforms of myosin heavy chain (MHC) during postnatal development was studied in the masseter muscle of the rabbit. Evidence is presented that in addition to adult fast and slow myosin, the rabbit masseter contains neonatal and 'cardiac' alpha-MHC. During postnatal growth myosin

  11. Enhanced protein electrophoresis technique for separating human skeletal muscle myosin heavy chain isoforms

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    Bamman, M. M.; Clarke, M. S.; Talmadge, R. J.; Feeback, D. L.

    1999-01-01

    Talmadge and Roy (J. Appl. Physiol. 1993, 75, 2337-2340) previously established a sodium dodecyl sulfate - polyacrylamide gel electrophoresis (SDS-PAGE) protocol for separating all four rat skeletal muscle myosin heavy chain (MHC) isoforms (MHC I, IIa, IIx, IIb); however, when applied to human muscle, the type II MHC isoforms (Ila, IIx) are not clearly distinguished. In this brief paper we describe a modification of the SDS-PAGE protocol which yields distinct and consistent separation of all three adult human MHC isoforms (MHC I, IIa, IIx) in a minigel system. MHC specificity of each band was confirmed by Western blot using three monoclonal IgG antibodies (mAbs) immunoreactive against MHCI (mAb MHCs, Novacastra Laboratories), MHCI+IIa (mAb BF-35), and MHCIIa+IIx (mAb SC-71). Results provide a valuable SDS-PAGE minigel technique for separating MHC isoforms in human muscle without the difficult task of casting gradient gels.

  12. Cloning of skeletal myosin heavy chain gene family from adult pleopod muscle and whole larvae of shrimps.

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    Koyama, Hiroki; Piyapattanakorn, Sanit; Watabe, Shugo

    2013-06-01

    The physiological and biological properties of skeletal muscle in crustacea have not been well understood compared with those of vertebrates. The present study focused on myosin, the major protein in skeletal muscle, from shrimps. In our previous study, two full-length genes encoding myosin heavy chain (MHC), a large subunit of the myosin molecule, were cloned from abdominal fast skeletal muscle of kuruma Marsupenaeus japonicus, black tiger Penaeus monodon and Pacific white Penaeus vannamei shrimps, and named as MHCa and MHCb. In this study, we renamed these as MHC1 and MHC2, respectively, due to the presence of various isoforms newly identified. Partial MHC sequences were identified from pleopod muscle of these shrimps. Two MHCs, named MHC3 and MHC4, were identified from pleopod muscle of kuruma shrimp, whereas two MHCs, named MHC4 and MHC5, were cloned from Pacific white shrimp pleopod. MHC3 was cloned only from black tiger shrimp pleopod. Partial MHC sequences from zoea, mysis, and postlarvae of black tiger and Pacific white shrimps were also determined. The phylogenetic tree demonstrated that most MHCs from pleopod muscle and larval MHCs formed clades with MHC1 and MHC2, respectively. These MHCs were considered to be of fast type, since MHC1 and MHC2 are fast-type MHCs according to our previous study. MHC5 obtained from pleopod muscle of Pacific white shrimp in this study was monophyletic with American lobster Homarus americanus S2 slow tonic MHC previously reported, indicating that MHC5 from Pacific white shrimp is of slow type. Copyright © 2013 Wiley Periodicals, Inc.

  13. Changes in muscle size and MHC composition in response to resistance exercise with heavy and light loading intensity

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    Holm, L.; Reitelseder, S.; Pedersen, T.G.

    2008-01-01

    resonance imaging, muscle biopsies were obtained bilaterally from vastus lateralis for determination of myosin heavy chain (MHC) composition, and maximal muscle strength was assessed by 1RM testing and in an isokinetic dynamometer at 60 degrees /s. Quadriceps muscle cross-sectional area increased (P ...Muscle mass accretion is accomplished by heavy-load resistance training. The effect of light-load resistance exercise has been far more sparsely investigated with regard to potential effect on muscle size and contractile strength. We applied a resistance exercise protocol in which the same...... individual trained one leg at 70% of one-repetition maximum (1RM) (heavy load, HL) while training the other leg at 15.5% 1RM (light load, LL). Eleven sedentary men (age 25 +/- 1 yr) trained for 12 wk at three times/week. Before and after the intervention muscle hypertrophy was determined by magnetic...

  14. Time course of myosin heavy chain transitions in neonatal rats: importance of innervation and thyroid state

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    Adams, G. R.; McCue, S. A.; Zeng, M.; Baldwin, K. M.

    1999-01-01

    During the postnatal period, rat limb muscles adapt to weight bearing via the replacement of embryonic (Emb) and neonatal (Neo) myosin heavy chains (MHCs) by the adult isoforms. Our aim was to characterize this transition in terms of the six MHC isoforms expressed in skeletal muscle and to determine the importance of innervation and thyroid hormone status on the attainment of the adult MHC phenotype. Neonatal rats were made hypothyroid via propylthiouracil (PTU) injection. In normal and PTU subgroups, leg muscles were unilaterally denervated at 15 days of age. The MHC profiles of plantaris (PLN) and soleus (Sol) muscles were determined at 7, 14, 23, and 30 days postpartum. At day 7, the Sol MHC profile was 55% type I, 30% Emb, and 10% Neo; in the PLN, the pattern was 60% Neo and 25% Emb. By day 30 the Sol and PLN had essentially attained an adult MHC profile in the controls. PTU augmented slow MHC expression in the Sol, whereas in the PLN it markedly repressed IIb MHC by retaining neonatal MHC expression. Denervation blunted the upregulation of IIb in the PLN and of Type I in the Sol and shifted the pattern to greater expression of IIa and IIx MHCs in both muscles. In contrast to previous observations, these findings collectively suggest that both an intact thyroid and innervation state are obligatory for the attainment of the adult MHC phenotype, particularly in fast-twitch muscles.

  15. Myosin heavy chain composition of single fibres from m. biceps brachii of male body builders

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    Klitgaard, H; Zhou, M.-Y.; Richter, Erik

    1990-01-01

    The myosin heavy chain (MHC) composition of single fibres from m. biceps brachii of young sedentary men (28 +/- 0.4 years, mean +/- SE, n = 4) and male body builders (25 +/- 2.0 years, n = 4) was analysed with a sensitive one-dimensional electrophoretic technique. Compared with sedentary men...... expression of MHC isoforms within histochemical type II fibres of human skeletal muscle with body building. Furthermore, in human skeletal muscle differences in expression of MHC isoforms may not always be reflected in the traditional histochemical classification of types I, IIa, IIb and IIc fibres....

  16. A single-chain fusion molecule consisting of peptide, major histocompatibility gene complex class I heavy chain and beta2-microglobulin can fold partially correctly, but binds peptide inefficiently

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    Sylvester-Hvid, C; Buus, S

    1999-01-01

    of a recombinant murine MHC-I molecule, which could be produced in large amounts in bacteria. The recombinant MHC-I protein was expressed as a single molecule (PepSc) consisting of the antigenic peptide linked to the MHC-I heavy chain and further linked to human beta2-microglobulin (hbeta2m). The PepSc molecule...... electrophoresis (SDS-PAGE). Serological analysis revealed the presence of some, but not all, MHC-I-specific epitopes. Biochemically, PepSc could bind peptide, however, rather ineffectively. We suggest that a partially correctly refolded MHC-I has been obtained....

  17. Single-fiber myosin heavy chain polymorphism during postnatal development: modulation by hypothyroidism

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    di Maso, N. A.; Caiozzo, V. J.; Baldwin, K. M.

    2000-01-01

    The primary objective of this study was to follow the developmental time course of myosin heavy chain (MHC) isoform transitions in single fibers of the rodent plantaris muscle. Hypothyroidism was used in conjunction with single-fiber analyses to better describe a possible linkage between the neonatal and fast type IIB MHC isoforms during development. In contrast to the general concept that developmental MHC isoform transitions give rise to muscle fibers that express only a single MHC isoform, the single-fiber analyses revealed a very high degree of MHC polymorphism throughout postnatal development. In the adult state, MHC polymorphism was so pervasive that the rodent plantaris muscles contained approximately 12-15 different pools of fibers (i.e., fiber types). The degree of polymorphism observed at the single-fiber level made it difficult to determine specific developmental schemes analogous to those observed previously for the rodent soleus muscle. However, hypothyroidism was useful in that it confirmed a possible link between the developmental regulation of the neonatal and fast type IIB MHC isoforms.

  18. Rapid switch-off of the human myosin heavy chain IIX gene after heavy load muscle contractions is sustained for at least four days.

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    Andersen, J L; Gruschy-Knudsen, T

    2018-02-01

    Long-term heavy load contractions decrease the relative amount of the myosin heavy chain (MHC) IIX isoform in human skeletal muscle, but the timing of the down-regulation in the short term is unknown. Untrained subjects performed two resistance bouts, in two consecutive days, with one leg, the other leg serving as a control (age 24±1, n=5). Muscle biopsies were obtained in both legs before, immediately after, and 24, 54, and 96 hours after exercise. Serial cryosection analysis combined immunohistochemistry and ATPase histochemistry with In Situ hybridization to identify the distribution of MHC isoforms and their corresponding transcripts, enabling identification of transitional fibers. Fibers positive solely for MHC IIX mRNA decreased in the exercised leg throughout the study period. At 96 hours post-exercise, no fibers solely expressed MHC IIX mRNA. In contrast, the number of fibers expressing MHC IIA mRNA increased throughout the study period. The percentage of fibers expressing mRNA for MHC I was unchanged in both legs at all time points. Pronounced depletion of glycogen in the MHC IIX fibers of the exercised leg verifies that the type IIX fibers were active during the heavy load contractions. Major mismatch between MHC at the mRNA and protein levels was only found in the fibers of the exercised leg. These data provide unequivocal in situ evidence of an immediate shutdown of the MHC IIX gene after resistance exercise. A further novel finding was that the silencing of the MHC IIX gene is sustained at least 4 days after removal of the stimulus. © 2017 John Wiley & Sons A/S. Published by John Wiley & Sons Ltd.

  19. Increased myosin heavy chain-beta with atrial expression of ventricular light chain-2 in canine cardiomyopathy.

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    Fuller, Geraldine A; Bicer, Sabahattin; Hamlin, Robert L; Yamaguchi, Mamoru; Reiser, Peter J

    2007-10-01

    Dilated cardiomyopathy is a naturally occurring disease in humans and dogs. Human studies have shown increased levels of myosin heavy chain (MHC)-beta in failing ventricles and the left atria (LA) and of ventricular light chain (VLC)-2 in the right atria in dilated cardiomyopathy. This study evaluates the levels of MHC-beta in all heart chambers in prolonged canine right ventricular pacing. In addition, we determined whether levels of VLC2 were altered in these hearts. Failing hearts demonstrated significantly increased levels of MHC-beta in the right atria, right atrial appendage, LA, left atrial appendage (LAA), and right ventricle compared with controls. Significant levels of VLC2 were detected in the right atria of paced hearts. Differences in MHC-beta expression were observed between the LA and the LAA of paced and control dogs. MHC-beta expression was significantly greater in the LA of paced and control dogs compared with their respective LAA. The cardiac myosin isoform shifts in this study were similar to those observed in end-stage human heart failure and more severe than those reported in less prolonged pacing models, supporting the use of this model for further study of end-stage human heart failure. The observation of consistent differences between sampling sites, especially LA versus LAA, indicates the need for rigorous sampling consistency in future studies.

  20. Myosin heavy chain composition of tiger (Panthera tigris) and cheetah (Acinonyx jubatus) hindlimb muscles.

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    Hyatt, Jon-Philippe K; Roy, Roland R; Rugg, Stuart; Talmadge, Robert J

    2010-01-01

    Felids have a wide range of locomotor activity patterns and maximal running speeds, including the very fast cheetah (Acinonyx jubatas), the roaming tiger (Panthera tigris), and the relatively sedentary domestic cat (Felis catus). As previous studies have suggested a relationship between the amount and type of activity and the myosin heavy chain (MHC) isoform composition of a muscle, we assessed the MHC isoform composition of selected hindlimb muscles from these three felid species with differing activity regimens. Using gel electrophoresis, western blotting, histochemistry, and immunohistochemistry with MHC isoform-specific antibodies, we compared the MHC composition in the tibialis anterior, medial gastrocnemius (MG), plantaris (Plt), and soleus muscles of the tiger, cheetah, and domestic cat. The soleus muscle was absent in the cheetah. At least one slow (type I) and three fast (types IIa, IIx, and IIb) MHC isoforms were present in the muscles of each felid. The tiger had a high combined percentage of the characteristically slower isoforms (MHCs I and IIa) in the MG (62%) and the Plt (86%), whereas these percentages were relatively low in the MG (44%) and Plt (55%) of the cheetah. In general, the MHC isoform characteristics of the hindlimb muscles matched the daily activity patterns of these felids: the tiger has daily demands for covering long distances, whereas the cheetah has requirements for speed and power. (c) 2009 Wiley-Liss, Inc.

  1. Shark class II invariant chain reveals ancient conserved relationships with cathepsins and MHC class II.

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    Criscitiello, Michael F; Ohta, Yuko; Graham, Matthew D; Eubanks, Jeannine O; Chen, Patricia L; Flajnik, Martin F

    2012-03-01

    The invariant chain (Ii) is the critical third chain required for the MHC class II heterodimer to be properly guided through the cell, loaded with peptide, and expressed on the surface of antigen presenting cells. Here, we report the isolation of the nurse shark Ii gene, and the comparative analysis of Ii splice variants, expression, genomic organization, predicted structure, and function throughout vertebrate evolution. Alternative splicing to yield Ii with and without the putative protease-protective, thyroglobulin-like domain is as ancient as the MHC-based adaptive immune system, as our analyses in shark and lizard further show conservation of this mechanism in all vertebrate classes except bony fish. Remarkable coordinate expression of Ii and class II was found in shark tissues. Conserved Ii residues and cathepsin L orthologs suggest their long co-evolution in the antigen presentation pathway, and genomic analyses suggest 450 million years of conserved Ii exon/intron structure. Other than an extended linker preceding the thyroglobulin-like domain in cartilaginous fish, the Ii gene and protein are predicted to have largely similar physiology from shark to man. Duplicated Ii genes found only in teleosts appear to have become sub-functionalized, as one form is predicted to play the same role as that mediated by Ii mRNA alternative splicing in all other vertebrate classes. No Ii homologs or potential ancestors of any of the functional Ii domains were found in the jawless fish or lower chordates. Copyright © 2011 Elsevier Ltd. All rights reserved.

  2. MHC class II tetramers made from isolated recombinant α and β chains refolded with affinity-tagged peptides

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    Braendstrup, Peter; Justesen, Sune Frederik Lamdahl; Osterbye, Thomas

    2013-01-01

    Targeting CD4+ T cells through their unique antigen-specific, MHC class II-restricted T cell receptor makes MHC class II tetramers an attractive strategy to identify, validate and manipulate these cells at the single cell level. Currently, generating class II tetramers is a specialized undertaking...... effectively limiting their use and emphasizing the need for improved methods of production. Using class II chains expressed individually in E. coli as versatile recombinant reagents, we have previously generated peptide-MHC class II monomers, but failed to generate functional class II tetramers. Adding...... a monomer purification principle based upon affinity-tagged peptides, we here provide a robust method to produce class II tetramers and demonstrate staining of antigen-specific CD4+ T cells. We also provide evidence that both MHC class II and T cell receptor molecules largely accept affinity-tagged peptides...

  3. Comparative genomic analysis of the arthropod muscle myosin heavy chain genes allows ancestral gene reconstruction and reveals a new type of 'partially' processed pseudogene

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    Kollmar Martin

    2008-02-01

    Full Text Available Abstract Background Alternative splicing of mutually exclusive exons is an important mechanism for increasing protein diversity in eukaryotes. The insect Mhc (myosin heavy chain gene produces all different muscle myosins as a result of alternative splicing in contrast to most other organisms of the Metazoa lineage, that have a family of muscle genes with each gene coding for a protein specialized for a functional niche. Results The muscle myosin heavy chain genes of 22 species of the Arthropoda ranging from the waterflea to wasp and Drosophila have been annotated. The analysis of the gene structures allowed the reconstruction of an ancient muscle myosin heavy chain gene and showed that during evolution of the arthropods introns have mainly been lost in these genes although intron gain might have happened in a few cases. Surprisingly, the genome of Aedes aegypti contains another and that of Culex pipiens quinquefasciatus two further muscle myosin heavy chain genes, called Mhc3 and Mhc4, that contain only one variant of the corresponding alternative exons of the Mhc1 gene. Mhc3 transcription in Aedes aegypti is documented by EST data. Mhc3 and Mhc4 inserted in the Aedes and Culex genomes either by gene duplication followed by the loss of all but one variant of the alternative exons, or by incorporation of a transcript of which all other variants have been spliced out retaining the exon-intron structure. The second and more likely possibility represents a new type of a 'partially' processed pseudogene. Conclusion Based on the comparative genomic analysis of the alternatively spliced arthropod muscle myosin heavy chain genes we propose that the splicing process operates sequentially on the transcript. The process consists of the splicing of the mutually exclusive exons until one exon out of the cluster remains while retaining surrounding intronic sequence. In a second step splicing of introns takes place. A related mechanism could be responsible for

  4. Myosin heavy chain expression in cranial, pectoral fin, and tail muscle regions of zebrafish embryos.

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    Peng, Mou-Yun; Wen, Hui-Ju; Shih, Li-Jane; Kuo, Ching-Ming; Hwang, Sheng-Ping L

    2002-12-01

    To investigate whether different myosin heavy chain (MHC) isoforms may constitute myofibrils in the trunk and tail musculature and if their respective expression may be regulated by spadetail (spt) and no tail (brachyury), we identified and characterized mRNA expression patterns of an embryonic- and tail muscle-specific MHC gene (named myhz2) during zebrafish development in wild type, spt, and ntl mutant embryos. The identified myhz2 MHC gene encodes a polypeptide containing 1,935 amino acids. Deduced amino acid comparisons showed that myhz2 MHC shared 92.6% sequence identity with that of carp fast skeletal MHC. Temporal and spatial myhz2 MHC mRNA expression patterns were analyzed by quantitative RT-PCR and whole-mount in situ hybridization using primer pairs and probes designed from the 3'-untranslated region (UTR). Temporally myhz2 MHC mRNA appears in pharyngula embryos and peaks in protruding-mouth larvae. The expression level decreased in 7-day-old hatching larvae, and mRNA expression was not detectable in adult fish. Spatially in pharyngula embryos, mRNA was localized only in the tail somite region, while in long-pec embryos, transcripts were also expressed in the two cranial muscle elements of the adductor mandibulae and medial rectus, as well as in pectoral fin muscles and the tail muscle region. Myhz2 MHC mRNA was expressed in most cranial muscle elements, pectoral fin muscles, and the tail muscle region of 3-day-old hatching larvae. In contrast, no expression of myhz2 MHC mRNA could be observed in spt prim-15 mutant embryos. In spt long-pec mutant embryos, transcripts were expressed in two cranial muscle elements and the tail muscle region, but not in pectoral fin muscles, while only trace amounts of myhz2 MHC mRNA were expressed in the remaining tail muscle region of 38 hpf and long-pec ntl mutant embryos. Copyright 2002 Wiley-Liss, Inc.

  5. Myosin heavy chain profile of equine gluteus medius muscle following prolonged draught-exercise training and detraining.

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    Serrano, A L; Rivero, J L

    2000-04-01

    Fourteen 4-year old Andalusian mares were used to examine the plasticity of myosin heavy chain (MHC) composition in horse skeletal muscle with heavy draught-exercise training and detraining. Seven horses underwent a training programme based on carriage exercises for 8 months. Afterwards, they were kept in paddocks for 3 months. The remaining seven animals were used as control horses. Three gluteus medius muscle biopsies were removed at depths of 20, 40 and 60 mm from each horse before (month 0), during the training (months 3 and 8) and after detraining (month 11). Myosin heavy chain composition was analysed by electrophoresis and immunohistochemically with anti-MHC monoclonal antibodies. Fibre areas, oxidative capacity and capillaries were studied histochemically. After 8 months of training, MHC-IIX and IIX fibres decreased whereas MHC-I and type I and I + IIA fibres increased. Neither MHC-IIA nor the percentage of IIA fibres changed when the data were considered as a whole, but the proportion of MHC-IIA increased in the superficial region of the muscle after 8 months of training. Mean areas of type II fibres were not affected by training and detraining, but the cross-sectional of type I fibres increased after 3 month of training and not further increases were recorded afterward. The percentage of high-oxidative capacity fibres and the number of capillaries per mm2 increased with training. Most of these muscular adaptations reverted after detraining. These results indicate that long term draught-exercise training induces a reversible transition of MHC composition in equine muscle in the order IIX --> IIA --> I. The physiological implication of these changes is an impact on the velocity of shortening and fatigue resistance of muscle fibres.

  6. Modes of salmonid MHC class I and II evolution differ from the primate paradigm

    NARCIS (Netherlands)

    Shum, B.P.; Guethlein, L.; Flodin, L.R.; Adkison, M.A.; Hedrick, R.P.; Nehring, R.B.; Stet, R.J.M.; Secombes, C.; Parham, P.

    2001-01-01

    Rainbow trout (Oncorhynchus mykiss) and brown trout (Salmo trutta) represent two salmonid genera separated for 15-20 million years. cDNA sequences were determined for the classical MHC class I heavy chain gene UBA and the MHC class II β-chain gene DAB from 15 rainbow and 10 brown trout. Both genes

  7. Protective Effects of Clenbuterol against Dexamethasone-Induced Masseter Muscle Atrophy and Myosin Heavy Chain Transition.

    Directory of Open Access Journals (Sweden)

    Daisuke Umeki

    Full Text Available Glucocorticoid has a direct catabolic effect on skeletal muscle, leading to muscle atrophy, but no effective pharmacotherapy is available. We reported that clenbuterol (CB induced masseter muscle hypertrophy and slow-to-fast myosin heavy chain (MHC isoform transition through direct muscle β2-adrenergic receptor stimulation. Thus, we hypothesized that CB would antagonize glucocorticoid (dexamethasone; DEX-induced muscle atrophy and fast-to-slow MHC isoform transition.We examined the effect of CB on DEX-induced masseter muscle atrophy by measuring masseter muscle weight, fiber diameter, cross-sectional area, and myosin heavy chain (MHC composition. To elucidate the mechanisms involved, we used immunoblotting to study the effects of CB on muscle hypertrophic signaling (insulin growth factor 1 (IGF1 expression, Akt/mammalian target of rapamycin (mTOR pathway, and calcineurin pathway and atrophic signaling (Akt/Forkhead box-O (FOXO pathway and myostatin expression in masseter muscle of rats treated with DEX and/or CB.Masseter muscle weight in the DEX-treated group was significantly lower than that in the Control group, as expected, but co-treatment with CB suppressed the DEX-induced masseter muscle atrophy, concomitantly with inhibition of fast-to-slow MHC isoforms transition. Activation of the Akt/mTOR pathway in masseter muscle of the DEX-treated group was significantly inhibited compared to that of the Control group, and CB suppressed this inhibition. DEX also suppressed expression of IGF1 (positive regulator of muscle growth, and CB attenuated this inhibition. Myostatin protein expression was unchanged. CB had no effect on activation of the Akt/FOXO pathway. These results indicate that CB antagonizes DEX-induced muscle atrophy and fast-to-slow MHC isoform transition via modulation of Akt/mTOR activity and IGF1 expression. CB might be a useful pharmacological agent for treatment of glucocorticoid-induced muscle atrophy.

  8. Myosin heavy-chain isoforms in the flight and leg muscles of hummingbirds and zebra finches.

    Science.gov (United States)

    Velten, Brandy P; Welch, Kenneth C

    2014-06-01

    Myosin heavy chain (MHC) isoform complement is intimately related to a muscle's contractile properties, yet relatively little is known about avian MHC isoforms or how they may vary with fiber type and/or the contractile properties of a muscle. The rapid shortening of muscles necessary to power flight at the high wingbeat frequencies of ruby-throated hummingbirds and zebra finches (25-60 Hz), along with the varied morphology and use of the hummingbird hindlimb, provides a unique opportunity to understand how contractile and morphological properties of avian muscle may be reflected in MHC expression. Isoforms of the hummingbird and zebra finch flight and hindlimb muscles were electrophoretically separated and compared with those of other avian species representing different contractile properties and fiber types. The flight muscles of the study species operate at drastically different contraction rates and are composed of different histochemically defined fiber types, yet each exhibited the same, single MHC isoform corresponding to the chicken adult fast isoform. Thus, despite quantitative differences in the contractile demands of flight muscles across species, this isoform appears necessary for meeting the performance demands of avian powered flight. Variation in flight muscle contractile performance across species may be due to differences in the structural composition of this conserved isoform and/or variation within other mechanically linked proteins. The leg muscles were more varied in their MHC isoform composition across both muscles and species. The disparity in hindlimb MHC expression between hummingbirds and the other species highlights previously observed differences in fiber type composition and thrust production during take-off. Copyright © 2014 the American Physiological Society.

  9. Interaction of thyroid state and denervation on skeletal myosin heavy chain expression

    Science.gov (United States)

    Haddad, F.; Arnold, C.; Zeng, M.; Baldwin, K.

    1997-01-01

    The goal of this study was to examine the effects of altered thyroid state and denervation (Den) on skeletal myosin heavy chain (MHC) expression in the plantaris and soleus muscles. Rats were subjected to unilateral denervation (Den) and randomly assigned to one of three groups: (1) euthyroid; (2) hyperthyroid; (3) and hypothyroid. Denervation caused severe muscle atrophy and muscle-type specific MHC transformation. Denervation transformed the soleus to a faster muscle, and its effects required the presence of circulating thyroid hormone. In contrast, denervation transformed the plantaris to a slower muscle independently of thyroid state. Furthermore, thyroid hormone effects did not depend upon innervation status in the soleus, while they required the presence of the nerve in the plantaris. Collectively, these findings suggest that both thyroid hormone and intact nerve (a) differentially affect MHC transformations in fast and slow muscle; and (b) are important factors in regulating the optimal expression of both type I and IIB MHC genes. This research suggests that for patients with nerve damage and/or paralysis, both muscle mass and biochemical properties can also be affected by the thyroid state.

  10. Proteolysis of the heavy chain of major histocompatibility complex class I antigens by complement component C1s

    DEFF Research Database (Denmark)

    Eriksson, H; Nissen, Mogens Holst

    1990-01-01

    weights of the fragments are in agreement with the cleavage located in the area between the disulphide loops of the alpha 2-and alpha 3-domains of the heavy chain. In addition human C1s complement is able to cleave H-2 antigens from mouse in a similar fashion but not rat MHC class I antigen or mouse MHC...... class II antigen (I-Ad). Mouse MHC class I antigen-specific determinants could also be detected in supernatant from mouse spleen cells incubated with C1r and C1s. These results indicate the presence in the body fluids of a non-membrane-bound soluble form of the alpha 1-and alpha 2-domains which...

  11. Premalignant quiescent melanocytic nevi do not express the MHC class I chain-related protein A

    Directory of Open Access Journals (Sweden)

    Mercedes B. Fuertes

    2011-08-01

    Full Text Available The MHC class I chain-related protein A (MICA is an inducible molecule almost not expressed by normal cells but strongly up-regulated in tumor cells. MICA-expressing cells are recognized by natural killer (NK cells, CD8+ aßTCR and ?dTCR T lymphocytes through the NKG2D receptor. Engagement of NKG2D by MICA triggers IFN-? secretion and cytotoxicity against malignant cells. Although most solid tumors express MICA and this molecule is a target during immune surveillance against tumors, it has been observed that high grade tumors from different histotypes express low amounts of cell surface MICA due to a metalloprotease- induced shedding. Also, melanomas develop after a complex process of neotransformation of normal melanocytes. However, the expression of MICA in premalignant stages (primary human quiescent melanocytic nevi remains unknown. Here, we assessed expression of MICA by flow cytometry using cell suspensions from 15 primary nevi isolated from 11 patients. When collected material was abundant, cell lysates were prepared and MICA expression was also analyzed by Western blot. We observed that MICA was undetectable in the 15 primary nevi (intradermic, junction, mixed, lentigo and congenital samples as well as in normal skin, benign lesions (seborrheic keratosis, premalignant lesions (actinic keratosis and benign basocellular cancer. Conversely, a primary recently diagnosed melanoma showed intense cell surface MICA. We conclude that the onset of MICA expression is a tightly regulated process that occurs after melanocytes trespass the stage of malignant transformation. Thus, analysis of MICA expression in tissue sections of skin samples may constitute a useful marker to differentiate between benign and malignant nevi.

  12. Mouse myeloma cells that make short immunoglobulin heavy chains: pleiotropic effects on glycosylation and chain assembly

    OpenAIRE

    1984-01-01

    Two variants in immunoglobulin heavy chain production, derived from the MPC 11 mouse myeloma cell line, make short heavy (H) chains with identical precise deletions of the CH3 domain. The CH3 domain is expressed in the H chain mRNA from both variants. Although in vitro translation of this mRNA produces one H chain species, deleted heavy chains are secreted as heavy-light (HL) and H2L2 moieties in contrast to MPC 11, which secretes only H2L2 . The heavy chains of HL apparently contain more car...

  13. Translocations affecting human immunoglobulin heavy chain locus

    Directory of Open Access Journals (Sweden)

    Sklyar I. V.

    2014-03-01

    Full Text Available Translocations involving human immunoglobulin heavy chain (IGH locus are implicated in different leukaemias and lymphomas, including multiple myeloma, mantle cell lymphoma, Burkitt’s lymphoma and diffuse large B cell lymphoma. We have analysed published data and identified eleven breakpoint cluster regions (bcr related to these cancers within the IgH locus. These ~1 kbp bcrs are specific for one or several types of blood cancer. Our findings could help devise PCR-based assays to detect cancer-related translocations, to identify the mechanisms of translocations and to help in the research of potential translocation partners of the immunoglobulin locus at different stages of B-cell differentiation.

  14. Effects of different activity and inactivity paradigms on myosin heavy chain gene expression in striated muscle

    Science.gov (United States)

    Baldwin, K. M.; Haddad, F.

    2001-01-01

    The goal of this mini-review is to summarize findings concerning the role that different models of muscular activity and inactivity play in altering gene expression of the myosin heavy chain (MHC) family of motor proteins in mammalian cardiac and skeletal muscle. This was done in the context of examining parallel findings concerning the role that thyroid hormone (T(3), 3,5,3'-triiodothyronine) plays in MHC expression. Findings show that both cardiac and skeletal muscles of experimental animals are initially undifferentiated at birth and then undergo a marked level of growth and differentiation in attaining the adult MHC phenotype in a T(3)/activity level-dependent fashion. Cardiac MHC expression in small mammals is highly sensitive to thyroid deficiency, diabetes, energy deprivation, and hypertension; each of these interventions induces upregulation of the beta-MHC isoform, which functions to economize circulatory function in the face of altered energy demand. In skeletal muscle, hyperthyroidism, as well as interventions that unload or reduce the weight-bearing activity of the muscle, causes slow to fast MHC conversions. Fast to slow conversions, however, are seen under hypothyroidism or when the muscles either become chronically overloaded or subjected to intermittent loading as occurs during resistance training and endurance exercise. The regulation of MHC gene expression by T(3) or mechanical stimuli appears to be strongly regulated by transcriptional events, based on recent findings on transgenic models and animals transfected with promoter-reporter constructs. However, the mechanisms by which T(3) and mechanical stimuli exert their control on transcriptional processes appear to be different. Additional findings show that individual skeletal muscle fibers have the genetic machinery to express simultaneously all of the adult MHCs, e.g., slow type I and fast IIa, IIx, and IIb, in unique combinations under certain experimental conditions. This degree of

  15. Expression of smooth muscle and non-muscle myosin heavy chain isoforms in cultured vascular smooth muscle cells

    International Nuclear Information System (INIS)

    Rovner, A.S.; Murphy, R.A.; Owens, G.K.

    1986-01-01

    Immunocytochemical studies of cultured smooth muscle cells (SMCs) have disagreed on the nature of myosin expression. This investigation was undertaken to test for the presence of heterogeneous myosin heavy chain (MHC) isoforms in cell culture as a possible explanation for these results. Previously, Rovner et al. detected two MHCs in intact smooth muscles which differed in molecular weight by ca. 4000 daltons (SM1 and SM2) using a 3-4% acrylamide gradient SDS gel system. When sub-confluent primary cultures of rat aorta SMCs were assayed by this system, SM1 and SM2 were seen, along with large amounts of a third, unique MHC, NM, which closely resembled the MHC from human platelet in size and antigenicity. Data from 35 S-methionine autoradiograms showed that the log growth phase SMC cultures were producing almost exclusively NM, but the growth arrest, post-confluent cultures synthesized increased relative amounts of the SM MHC forms and contained comparable amounts of SM1, SM2, and NM. The same patterns of MHC synthesis were seen in sub-passaged SMCs. The expression of the SM-specific forms of myosin in quiescent, post-confluent cultures parallels that of smooth muscle actin suggesting that density induced growth arrest promotes cytodifferentiation in cultured vascular SMCs

  16. Changes in muscle size and MHC composition in response to resistance exercise with heavy and light loading intensity

    DEFF Research Database (Denmark)

    Holm, Lars; Reitelseder, Søren; Pedersen, T.G.

    2008-01-01

    Muscle mass accretion is accomplished by heavy-load resistance training. The effect of light-load resistance exercise has been far more sparsely investigated with regard to potential effect on muscle size and contractile strength. We applied a resistance exercise protocol in which the same indivi...... in healthy young men. However, LL resistance training was inferior to HL training in evoking adaptive changes in muscle size and contractile strength and was insufficient to induce changes in MHC composition.......Muscle mass accretion is accomplished by heavy-load resistance training. The effect of light-load resistance exercise has been far more sparsely investigated with regard to potential effect on muscle size and contractile strength. We applied a resistance exercise protocol in which the same.......05) in HL but remained unchanged in LL (4 +/- 5%, not significant). Finally, MHC IIX protein expression was decreased with HL but not LL, despite identical total workload in HL and LL. Our main finding was that LL resistance training was sufficient to induce a small but significant muscle hypertrophy...

  17. Reduction in beta-myosin heavy chains in stunned myocardium as assessed by nondenaturing gel electrophoresis.

    Science.gov (United States)

    Garcia, S C; Pomblum, V J; Gams, E; Rupp, H; Schipke, J D

    2007-09-01

    Myosin plays a key role in the structure and function of cardiac muscle. Three myosin isoenzymes (V(1), V(2), and V(3)) with different ATPase activities have been identified in mammalian ventricles based on their heavy chain constituents. The relative amount of myosin isoenzymes changes under physiological and pathological conditions. Until now, myosin isoenzymes have frequently been determined using either tube gel (nondenaturing) polyacrylamide gel electrophoresis (PAGE), or gradient or uniform sodium dodecyl sulfate (denaturing) PAGE. Both methods have disadvantages, e.g., a long running time. We developed, therefore, a uniform, nondenaturing PAGE with slab minigel format for analyzing the myosin isoenzymes in normoxic and stunned rabbit hearts. In normoxic hearts of adult rabbits, V(3) predominated over V(1) (46 vs 41%). In turn, in the stunned hearts, V(1) predominated over V(3) (70 vs 30%), and the heterodimeric V(2) was not anymore detectable. This alteration appears to result from a selective loss of myosin heavy chain (MHC)-beta. In parallel, the biochemical markers troponin I and creatine kinase were increased in the stunned hearts. We suggest that alterations of myosin isoenzymes in stunned myocardium can be monitored with native PAGE. The present analysis of myosin isoenzyme appears thus as a new tool for evaluating defects in MHC dimer formation in postischemic hearts.

  18. Immunolabelling, histochemistry and in situ hybridisation in human skeletal muscle fibres to detect myosin heavy chain expression at the protein and mRNA level

    Science.gov (United States)

    SERRANO, A. L.; PÉREZ, MARGARITA; LUCÍA, A.; CHICHARRO, J. L.; QUIROZ-ROTHE, E.; RIVERO, J. L. L.

    2001-01-01

    The distribution of muscle fibres classified on the basis of their content of different myosin heavy chain (MHC) isoforms was analysed in vastus lateralis muscle biopsies of 15 young men (with an average age of 22 y) by correlating immunohistochemistry with specific anti-MHC monoclonal antibodies, myofibrillar ATPase (mATPase) histochemistry and in situ hybridisation with probes specific for MHC β-slow, MHC-IIA and MHC-IIX. The characterisation of a large number of individual fibres was compared and correlated on a fibre-to-fibre basis. The panel of monoclonal antibodies used in the study allowed classification of human skeletal muscle fibres into 5 categories according to the MHC isoform they express at the protein level, types I, I+IIA, IIA, IIAX and IIX. Hybrid fibres coexpressing two isoforms represented a considerable proportion of the fibre composition (about 14%) and were clearly underestimated by mATPase histochemistry. For a very high percentage of fibres there was a precise correspondence between the MHC protein isoforms and mRNA transcripts. The integrated methods used demonstrate a high degree of precision of the immunohistochemical procedure used for the identification and quantification of human skeletal muscle fibre types. The monoclonal antibody S5-8H2 is particularly useful for identifying hybrid IIAX fibres. This protocol offers new prospects for muscle fibre classification in human experimental studies. PMID:11554510

  19. Complement component C1r mediated cleavage of the heavy chain of the major histocompatibility class I antigens

    DEFF Research Database (Denmark)

    Eriksson, H; Nissen, Mogens Holst

    1992-01-01

    Apart from cleaving C1s, we demonstrate for the first time that: 1) at concentrations found in serum, the activated forms of the complement components C1r in addition to C1s can cleave the heavy chain of MHC class I antigens, 2) the cleavage by C1r and C1s is seemingly dependent upon a native con......-chain of MHC class I was shown to take place between the alpha 2- and alpha 3- domains as estimated by the Con A-Sepharose precipitation pattern on SDS-PAGE. The alpha 1/alpha 2 fragment was still shown to interact with beta 2-microglobulin as shown by immunoprecipitation....

  20. Structural and Functional Characterization of a Single-chain Peptide-MHC Molecule that Modulates both Naive and Activated CD8plus T Cells

    Energy Technology Data Exchange (ETDEWEB)

    D Samanta; G Mukherjee; U Ramagopal; R Chaparro; S Nathenson; T DiLorenzo; S Almo

    2011-12-31

    Peptide-MHC (pMHC) multimers, in addition to being tools for tracking and quantifying antigen-specific T cells, can mediate downstream signaling after T-cell receptor engagement. In the absence of costimulation, this can lead to anergy or apoptosis of cognate T cells, a property that could be exploited in the setting of autoimmune disease. Most studies with class I pMHC multimers used noncovalently linked peptides, which can allow unwanted CD8{sup +} T-cell activation as a result of peptide transfer to cellular MHC molecules. To circumvent this problem, and given the role of self-reactive CD8{sup +} T cells in the development of type 1 diabetes, we designed a single-chain pMHC complex (scK{sup d}.IGRP) by using the class I MHC molecule H-2K{sup d} and a covalently linked peptide derived from islet-specific glucose-6-phosphatase catalytic subunit-related protein (IGRP{sub 206-214}), a well established autoantigen in NOD mice. X-ray diffraction studies revealed that the peptide is presented in the groove of the MHC molecule in canonical fashion, and it was also demonstrated that scK{sup d}.IGRP tetramers bound specifically to cognate CD8{sup +} T cells. Tetramer binding induced death of naive T cells and in vitro- and in vivo-differentiated cytotoxic T lymphocytes, and tetramer-treated cytotoxic T lymphocytes showed a diminished IFN-{gamma} response to antigen stimulation. Tetramer accessibility to disease-relevant T cells in vivo was also demonstrated. Our study suggests the potential of single-chain pMHC tetramers as possible therapeutic agents in autoimmune disease. Their ability to affect the fate of naive and activated CD8{sup +} T cells makes them a potential intervention strategy in early and late stages of disease.

  1. Regulation of an antisense RNA with the transition of neonatal to IIb myosin heavy chain during postnatal development and hypothyroidism in rat skeletal muscle.

    Science.gov (United States)

    Pandorf, Clay E; Jiang, Weihua; Qin, Anqi X; Bodell, Paul W; Baldwin, Kenneth M; Haddad, Fadia

    2012-04-01

    Postnatal development of fast skeletal muscle is characterized by a transition in expression of myosin heavy chain (MHC) isoforms, from primarily neonatal MHC at birth to primarily IIb MHC in adults, in a tightly coordinated manner. These isoforms are encoded by distinct genes, which are separated by ∼17 kb on rat chromosome 10. The neonatal-to-IIb MHC transition is inhibited by a hypothyroid state. We examined RNA products [mRNA, pre-mRNA, and natural antisense transcript (NAT)] of developmental and adult-expressed MHC genes (embryonic, neonatal, I, IIa, IIx, and IIb) at 2, 10, 20, and 40 days after birth in normal and thyroid-deficient rat neonates treated with propylthiouracil. We found that a long noncoding antisense-oriented RNA transcript, termed bII NAT, is transcribed from a site within the IIb-Neo intergenic region and across most of the IIb MHC gene. NATs have previously been shown to mediate transcriptional repression of sense-oriented counterparts. The bII NAT is transcriptionally regulated during postnatal development and in response to hypothyroidism. Evidence for a regulatory mechanism is suggested by an inverse relationship between IIb MHC and bII NAT in normal and hypothyroid-treated muscle. Neonatal MHC transcription is coordinately expressed with bII NAT. A comparative phylogenetic analysis also suggests that bII NAT-mediated regulation has been a conserved trait of placental mammals for most of the eutherian evolutionary history. The evidence in support of the regulatory model implicates long noncoding antisense RNA as a mechanism to coordinate the transition between neonatal and IIb MHC during postnatal development.

  2. Thyroid hormone partially corrects the effect of diabetes on mysoin heavy chain RNAs in the rat ventricle

    International Nuclear Information System (INIS)

    Barrieux, A.; Dillmann, W.H.

    1986-01-01

    The relative abundance of the 2 cardiac myosin heavy chains (MHH-α and MHC-β) and their corresponding RNAs is similarly affected by hypothyroidism and diabetes in the rat ventricle. Since circulating levels of thyroid hormone (T 3 ) are significantly decreased in diabetes the decreased RNA-α and increased RNA-β associated with diabetes may be related to T 3 deficiency. Chronically diabetic rats were injected with T 3 , insulin (I), or both and sacrificed between 1 and 12 hrs after injection, MHC RNA was quantified by hybridization of total RNA to a [ 32 P]-cDNA MHC-α probe. Total MHC RNA was measured by retention of S1-resistant label on DE-81 while RNA-α and RNA-β were quantified by separation of intact (α) and partially digested (β) probe by gel electrophoresis. Total MHC RNA was not changed by T 3 or I (.9-1.2 ng/μg of cellular RNA). T 3 and I elicited a very rapid increase in RNA-α (18% in untreated to 38% (I) and 47% (T 3 within 1 hr). I administered either 7 hr before or 1 hr after T 3 did not modify the RNA-α increase observed after T 3 alone. However, the response of diabetic rats to T 3 was markedly different from that of hypothyroid rats. Conclusions: 1) T 3 in diabetic rats does not mimick the effect of T 3 in hypothyroid rats; it may simply impose a hyperthyroid state on the existing diabetes and 2) since neither T 3 nor I are able to increase RNA-α to control levels within 12 hrs, neither hormone is sufficient to regulate the expression of MHC RNAs

  3. Immunoglobulin heavy chain exclusion in the shark.

    Directory of Open Access Journals (Sweden)

    Karolina Malecek

    2008-06-01

    Full Text Available The adaptive immune system depends on specific antigen receptors, immunoglobulins (Ig in B lymphocytes and T cell receptors (TCR in T lymphocytes. Adaptive responses to immune challenge are based on the expression of a single species of antigen receptor per cell; and in B cells, this is mediated in part by allelic exclusion at the Ig heavy (H chain locus. How allelic exclusion is regulated is unclear; we considered that sharks, the oldest vertebrates possessing the Ig/TCR-based immune system, would yield insights not previously approachable and reveal the primordial basis of the regulation of allelic exclusion. Sharks have an IgH locus organization consisting of 15-200 independently rearranging miniloci (VH-D1-D2-JH-Cmu, a gene organization that is considered ancestral to the tetrapod and bony fish IgH locus. We found that rearrangement takes place only within a minilocus, and the recombining gene segments are assembled simultaneously and randomly. Only one or few H chain genes were fully rearranged in each shark B cell, whereas the other loci retained their germline configuration. In contrast, most IgH were partially rearranged in every thymocyte (developing T cell examined, but no IgH transcripts were detected. The distinction between B and T cells in their IgH configurations and transcription reveals a heretofore unsuspected chromatin state permissive for rearrangement in precursor lymphocytes, and suggests that controlled limitation of B cell lineage-specific factors mediate regulated rearrangement and allelic exclusion. This regulation may be shared by higher vertebrates in which additional mechanistic and regulatory elements have evolved with their structurally complex IgH locus.

  4. Effects of chronic Akt/mTOR inhibition by rapamycin on mechanical overload-induced hypertrophy and myosin heavy chain transition in masseter muscle.

    Science.gov (United States)

    Umeki, Daisuke; Ohnuki, Yoshiki; Mototani, Yasumasa; Shiozawa, Kouichi; Fujita, Takayuki; Nakamura, Yoshiki; Saeki, Yasutake; Okumura, Satoshi

    2013-01-01

    To examine the effects of the Akt/mammalian target of rapamycin (mTOR) pathway on masseter muscle hypertrophy and myosin heavy chain (MHC) transition in response to mechanical overload, we analyzed the effects of bite-opening (BO) on the hypertrophy and MHC composition of masseter muscle of BO-rats treated or not treated with rapamycin (RAPA), a selective mTOR inhibitor. The masseter muscle weight in BO-rats was significantly greater than that in controls, and this increase was attenuated by RAPA treatment. Expression of slow-twitch MHC isoforms was significantly increased in BO-rats with/without RAPA treatment, compared with controls, but the magnitude of the increase was much smaller in RAPA-treated BO-rats. Phosphorylation of p44/42 MAPK (ERK1/2), which preserves fast-twitch MHC isoforms in skeletal muscle, was significantly decreased in BO-rats, but the decrease was abrogated by RAPA treatment. Calcineurin signaling is known to be important for masseter muscle hypertrophy and fast-to-slow MHC isoform transition, but expression of known calcineurin activity modulators was unaffected by RAPA treatment. Taken together, these results indicate that the Akt/mTOR pathway is involved in both development of masseter muscle hypertrophy and fast-to-slow MHC isoform transition in response to mechanical overload with inhibition of the ERK1/2 pathway and operates independently of the calcineurin pathway.

  5. Ginger extract mitigates ethanol-induced changes of alpha and beta - myosin heavy chain isoforms gene expression and oxidative stress in the heart of male wistar rats.

    Science.gov (United States)

    Shirpoor, Alireza; Zerehpoosh, Mitra; Ansari, Mohammad Hasan Khadem; Kheradmand, Fatemeh; Rasmi, Yousef

    2017-09-01

    The association between ethanol consumption and heart abnormalities, such as chamber dilation, myocyte damage, ventricular hypertrophy, and hypertension is well known. However, underlying molecular mediators involved in ethanol-induced heart abnormalities remain elusive. The aim of this study was to investigate the effect of chronic ethanol exposure on alpha and beta - myosin heavy chain (MHC) isoforms gene expression transition and oxidative stress in rats' heart. It was also planned to find out whether ginger extract mitigated the abnormalities induced by ethanol in rats' heart. Male wistar rats were divided into three groups of eight animals as follows: Control, ethanol, and ginger extract treated ethanolic (GETE) groups. After six weeks of treatment, the results revealed a significant increase in the β-MHC gene expression, 8- OHdG amount, and NADPH oxidase level. Furthermore, a significant decrease in the ratio of α-MHC/β-MHC gene expression to the amount of paraoxonase enzyme in the ethanol group compared to the control group was found. The consumption of Ginger extract along with ethanol ameliorated the changes in MHC isoforms gene expression and reduced the elevated amount of 8-OHdG and NADPH oxidase. Moreover, compared to the consumption of ethanol alone, it increased the paraoxonase level significantly. These findings indicate that ethanol-induced heart abnormalities may in part be associated with MHC isoforms changes mediated by oxidative stress, and that these effects can be alleviated by using ginger extract as an antioxidant molecule. Copyright © 2017 Elsevier B.V. All rights reserved.

  6. Frequency patterns of T-cell exposed motifs in immunoglobulin heavy chain peptides presented by MHCs

    Directory of Open Access Journals (Sweden)

    Robert D. Bremel

    2014-10-01

    Full Text Available Immunoglobulins are highly diverse protein sequences that are processed and presented to T-cells by B-cells and other antigen presenting cells. We examined a large dataset of immunoglobulin heavy chain variable regions (IGHV to assess the diversity of T-cell exposed motifs (TCEM. TCEM comprise those amino acids in a MHC-bound peptide which face outwards, surrounded by the MHC histotope, and which engage the T-cell receptor. Within IGHV there is a distinct pattern of predicted MHC class II binding and a very high frequency of re-use of the TCEMs. The re-use frequency indicates that only a limited number of different cognate T-cells are required to engage many different clonal B-cells. The amino acids in each outward-facing TCEM are intercalated with the amino acids of inward-facing MHC groove-exposed motifs (GEM. Different GEM may have differing, allele-specific, MHC binding affinities. The intercalation of TCEM and GEM in a peptide allows for a vast combinatorial repertoire of epitopes, each eliciting a different response. Outcome of T-cell receptor binding is determined by overall signal strength, which is a function of the number of responding T-cells and the duration of engagement. Hence, the frequency of T-cell exposed motif re-use appears to be an important determinant of whether a T-cell response is stimulatory or suppressive. The frequency distribution of TCEMs implies that somatic hypermutation is followed by clonal expansion that develop along repeated pathways. The observations of TCEM and GEM derived from immunoglobulins suggest a relatively simple, yet powerful, mechanism to correlate T-cell polyspecificity, through re-use of TCEMs, with a very high degree of specificity achieved by combination with a diversity of GEMs. The frequency profile of TCEMs also points to an economical mechanism for maintaining T-cell memory, recall, and self-discrimination based on an endogenously generated profile of motifs.

  7. Skeletal muscle myosin heavy chain isoform content in relation to gonadal hormones and anabolic-catabolic balance in trained and untrained men.

    Science.gov (United States)

    Grandys, Marcin; Majerczak, Joanna; Karasinski, Janusz; Kulpa, Jan; Zoladz, Jerzy A

    2012-12-01

    Gonadal hormones and anabolic-catabolic hormone balance have potent influence on skeletal muscle tissue, but little is known about their action with regard to myosin heavy chain (MHC) transformation in humans. We investigated the relationship between skeletal muscle MHC isoform content in the vastus lateralis muscle and basal testosterone (T) concentration in 3 groups of subjects: endurance trained (E), sprint/strength trained (S), and untrained (U) young men. We have also determined basal sex hormone-binding globulin and cortisol (C) concentrations in untrained subjects to examine the relationship between MHC composition and the anabolic-catabolic hormone balance. Moreover, basal free testosterone (fT) and bioavailable testosterone (bio-T) concentrations were calculated for this subgroup. Despite significant differences in MHC isoform content (69.4 ± 2.39%, 61.4 ± 8.04%, and 37.5 ± 13.80% of MHC-2 for groups S, U, and E, respectively, Kruskal-Wallis: H = 18.58, p 0.5). We have also found that in the U group, type 2 MHC in the vastus lateralis muscle is positively correlated with basal fT:C ratio (r = 0.63, p = 0.01). It is concluded that the differences in the training history and training specificity can be distinguished with regard to the MHC composition but not with regard to the basal T concentration. Simultaneously, it has been shown that MHC isoform content in human vastus lateralis muscle may be related to basal anabolic-catabolic hormone balance, and this hypothesis needs further investigation.

  8. Diversity Analysis of the Immunoglobulin M Heavy Chain Gene in ...

    African Journals Online (AJOL)

    A full-length cDNA encoding the immunoglobulin (IgM) heavy chain gene of Nile tilapia was successfully cloned using the 5' and 3' RACE techniques. The complete cDNA of the Nile tilapia IgM heavy chain gene is 1,921 bp in length and has an open reading frame (ORF) of 1,740 bp, which corresponds to 580 amino acid ...

  9. Stability of llama heavy chain antibody fragments under extreme conditions

    NARCIS (Netherlands)

    Dolk, E.

    2004-01-01

    Camelids have next to their normal antibodies, a unique subset of antibodies lacking light chains. The resulting single binding domain, VHH, of these heavy chain antibodies consequently have unique properties. A high stability is one of these properties, which was investigated in this thesis. The

  10. Premalignant quiescent melanocytic nevi do not express the MHC class I chain-related protein A Los nevos melanocíticos premalignos quiescentes no expresan la molécula MHC class I chain-related protein A

    Directory of Open Access Journals (Sweden)

    Mercedes B. Fuertes

    2011-08-01

    Full Text Available The MHC class I chain-related protein A (MICA is an inducible molecule almost not expressed by normal cells but strongly up-regulated in tumor cells. MICA-expressing cells are recognized by natural killer (NK cells, CD8+ aßTCR and ?dTCR T lymphocytes through the NKG2D receptor. Engagement of NKG2D by MICA triggers IFN-? secretion and cytotoxicity against malignant cells. Although most solid tumors express MICA and this molecule is a target during immune surveillance against tumors, it has been observed that high grade tumors from different histotypes express low amounts of cell surface MICA due to a metalloprotease- induced shedding. Also, melanomas develop after a complex process of neotransformation of normal melanocytes. However, the expression of MICA in premalignant stages (primary human quiescent melanocytic nevi remains unknown. Here, we assessed expression of MICA by flow cytometry using cell suspensions from 15 primary nevi isolated from 11 patients. When collected material was abundant, cell lysates were prepared and MICA expression was also analyzed by Western blot. We observed that MICA was undetectable in the 15 primary nevi (intradermic, junction, mixed, lentigo and congenital samples as well as in normal skin, benign lesions (seborrheic keratosis, premalignant lesions (actinic keratosis and benign basocellular cancer. Conversely, a primary recently diagnosed melanoma showed intense cell surface MICA. We conclude that the onset of MICA expression is a tightly regulated process that occurs after melanocytes trespass the stage of malignant transformation. Thus, analysis of MICA expression in tissue sections of skin samples may constitute a useful marker to differentiate between benign and malignant nevi.MHC class I chain-related protein A (MICA es una molécula casi ausente en células normales pero sobre-expresada por células tumorales, que promueve el reconocimiento por células citotóxicas naturales (natural killer o NK y por

  11. Enhanced Prevalence of Plasmatic Soluble MHC Class I Chain-Related Molecule in Vascular Pregnancy Diseases

    Directory of Open Access Journals (Sweden)

    Jean Baptiste Haumonte

    2014-01-01

    Full Text Available The major histocompatibility complex class I related chain (MIC is a stress-inducible protein modulating the function of immune natural killer (NK cells, a major leukocyte subset involved in proper trophoblast invasion and spiral artery remodeling. Aim of the study was to evaluate whether upregulation of soluble MIC (sMIC may reflect immune disorders associated to vascular pregnancy diseases (VPD. sMIC was more frequently detected in the plasma of women with a diagnostic of VPD (32% than in normal term-matched pregnancies (1.6%, P<0.0001, with highest prevalence in intrauterine fetal death (IUDF, 44% and vascular intrauterine growth restriction (IUGR, 39%. sMIC levels were higher in preeclampsia (PE than in IUFD (P<0.01 and vascular IUGR (P<0.05. sMIC detection was associated with bilateral early diastolic uterine notches (P=0.037, thrombocytopenia (P=0.03, and high proteinuria (P=0.03 in PE and with the vascular etiology of IUGR (P=0.0038. Incubation of sMIC-positive PE plasma resulted in downregulation of NKG2D expression and NK cell-mediated IFN-γ production in vitro. Our work thus suggests that detection of sMIC molecule in maternal plasma may constitute a hallmark of altered maternal immune functions that contributes to vascular disorders that complicate pregnancy, notably by impairing NK-cell mediated production of IFN-γ, an essential cytokine favoring vascular modeling.

  12. MHC protocols

    National Research Council Canada - National Science Library

    Powis, Stephen H; Vaughan, Robert W

    2003-01-01

    ... because it contains genes encoding components of the complement pathway. The entire human MHC has recently been sequenced (1) and each subregion is now known to contain many other genes, a number of which have immunological functions. The study of polymorphism within the MHC is well established, because the region contains the highly polymorphic HLA genes. HLA polym...

  13. All-trans retinoic acid increases the expression of oxidative myosin heavy chain through the PPARδ pathway in bovine muscle cells derived from satellite cells.

    Science.gov (United States)

    Kim, Jongkyoo; Wellmann, Kimberly B; Smith, Zachary K; Johnson, Bradley J

    2018-04-24

    All-trans retinoic acid (ATRA) has been associated with various physiological phenomenon in mammalian adipose tissue and skeletal muscle. We hypothesized that ATRA may affect skeletal muscle fiber type in bovine satellite cell culture through various transcriptional processes. Bovine primary satellite cell (BSC) culture experiments were conducted to determine dose effects of ATRA on expression of genes and protein levels related to skeletal muscle fiber type and metabolism. The semimembranosus from crossbred steers (n = 2 steers), aged approximately 24 months, were used to isolate BSC for 3 separate assays. Myogenic differentiation was induced using 3% horse serum upon cultured BSC with increasing doses (0, 1, 10, 100, 1000 nM) of ATRA. After 96 h of incubation, cells were harvested and used to measure the gene expression of protein kinase B (Akt), AMP-activated protein kinase alpha (AMPK), glucose transporter 4 (GLUT4), myogenin, lipoprotein lipase (LPL), myosin heavy chain (MHC) I, MHC IIA,MHC IIX, insulin like growth factor -1 (IGF-1), Peroxisome proliferator activated receptor gamma (PPARγ), PPARδ, and Smad transcription factor 3 (SMAD3) mRNA relative to ribosomal protein subunit 9 (RPS9). The mRNA expression of LPL was increased (P < 0.05) with 100 and 1000nM of ATRA. Expression of GLUT4 was altered (P < 0.05) by ATRA. The treatment of ATRA (1000nM) also increased (P < 0.05) mRNA gene expression of SMAD3. The gene expression of both PPARδ and PPARγ were increased (P < 0.05) with 1000nM of ATRA. Protein level of PPARδ was also affected (P < 0.05) by 1000nM of ATRA and resulted in a greater (P < 0.05) protein level of PPARδ compared to CON. All-trans retinoic acid (10nM) increased gene expression of MHC I (P < 0.05) compared to CON. Expression of MHC IIA was also influenced (P < 0.05) by ATRA. The mRNA expression of MHC IIX was decreased (P < 0.05) with 100 and 1000nM of ATRA.In muscle cells, ATRA may cause muscle fibers to transition towards the MHC

  14. Molecular regulation of MHC class I chain-related protein A expression after HDAC-inhibitor treatment of Jurkat T cells

    DEFF Research Database (Denmark)

    Andresen, Lars; Jensen, Helle; Pedersen, Marianne T

    2007-01-01

    In this study, we characterize the molecular signal pathways that lead to MHC class I chain-related protein A (MICA) expression after histone deacetylase (HDAC)-inhibitor (HDAC-i) treatment of Jurkat T cells. Chelating calcium with BAPTA-AM or EGTA potently inhibited HDAC- and CMV-mediated MICA......1 site from position -113 to -93 relative to the mRNA start site was important for HDAC and CMV-induced promoter activity. Sp1 was subsequently shown to be important, as targeted mutation of the Sp1 binding sequence or siRNA mediated down modulation of Sp1-inhibited MICA promoter activity...

  15. Heavy subgraph pairs for traceability of block-chains

    Directory of Open Access Journals (Sweden)

    Li Binlong

    2014-05-01

    Full Text Available A graph is called traceable if it contains a Hamilton path, i.e., a path containing all its vertices. Let G be a graph on n vertices. We say that an induced subgraph of G is o−1-heavy if it contains two nonadjacent vertices which satisfy an Ore-type degree condition for traceability, i.e., with degree sum at least n−1 in G. A block-chain is a graph whose block graph is a path, i.e., it is either a P1, P2, or a 2-connected graph, or a graph with at least one cut vertex and exactly two end-blocks. Obviously, every traceable graph is a block-chain, but the reverse does not hold. In this paper we characterize all the pairs of connected o−1-heavy graphs that guarantee traceability of block-chains. Our main result is a common extension of earlier work on degree sum conditions, forbidden subgraph conditions and heavy subgraph conditions for traceability

  16. Gm typing by immunoglobulin heavy-chain gene RFLP analysis.

    OpenAIRE

    Jazwinska, E C; Dunckley, H; Propert, D N; Gatenby, P A; Serjeantson, S W

    1988-01-01

    This study was undertaken to investigate a means of assigning Gm allotypes to Caucasians by RFLP analysis. A single immunoglobulin heavy-chain gamma-4 cDNA probe (HU gamma 4) was hybridized with genomic DNA digested separately with two restriction enzymes, TaqI and PvuII. Results showed excellent correlation (P less than .001) between serologically defined Gm allotypes G1m(1), G1m(2), G2m(23), and G1m;G3m (3;5,10) and RFLPs identified with the (HU gamma 4) probe. We conclude that it is now po...

  17. Tubulointerstitial nephritis accompanying gamma-heavy chain deposition and gamma-heavy chain restricted plasma cells in the kidney.

    Science.gov (United States)

    Nayer, Ali; Green, Dollie F; Gonzalez-Suarez, Maria L; Sujoy, Victoria; Ikpatt, Offiong F; Thomas, David B

    2014-09-01

    Monoclonal immunoglobulin heavy chain (HC) diseases are rare proliferative disorders of B lymphocytes or plasma cells characterized by the presence of monoclonal α-, µ-, or γ-HC without associated light chains in the blood, urine, or both. We report a 59-year-old woman with a history of Hodgkin disease who developed hypercalcemia, proteinuria, and impaired kidney function. Protein electrophoresis and immunofixation displayed γ-HC without associated light chains in the serum and urine. Pathologic examination demonstrated severe tubulointerstitial nephritis associated with diffuse and strong linear staining of the glomerular and tubular basement membranes as well as Bowman capsules for γ-HC, but not for κ- or λ-light chains. Immunohistochemical examination of the kidney and bone marrow demonstrated numerous CD138+ plasma cells immunoreactive for γ-HC, but not for κ- or λ-light chains. This is the first report of tubulointerstitial nephritis associated with γ-HC deposition and γ-HC restricted plasma cells in the kidney. This report heightens awareness about tubulointerstitial nephritis as a possible manifestation of γ-HC deposition in the kidney.

  18. Distribution of fast myosin heavy chain-based muscle fibres in the gluteus medius of untrained horses: mismatch between antigenic and ATPase determinants

    Science.gov (United States)

    LINNANE, LINDA; SERRANO, A. L.; RIVERO, J. L. L.

    1999-01-01

    The distribution of muscle fibres classified on the basis of their content of different myosin heavy chain (MHC) isoforms was analysed in muscle biopsies from the gluteus medius of adult untrained horses by correlating immunohistochemistry with specific anti-MHC monoclonal antibodies and standard myofibrillar ATPase (mATPase) histochemistry. Percutaneous needle biopsies were taken at 3 depths (20, 40 and 60 mm) from 4 4-y-old Andalusian stallions. The percentage of ‘pure’ I MHC fibres increased whereas that for pure IIX MHC fibres decreased from the most superficial to the deepest sampling site. Within the fast fibres, types IIA and IIAX MHC-classified fibres were proportionately more abundant in the deepest sampling site than in the superficial region of the muscle. The immunohistochemical and histochemical characterisation of a large number of single fibres (n=1375) was compared and correlated on a fibre-to-fibre basis. The results showed that 40% of the fibres analysed were pure type I (expressing only MHC-I); they showed correct matching between their antigenic and mATPase determinants. In contrast, within the fast fibres, a considerable proportion of fibres were found showing a mismatch between their immunohistochemical and mATPase profiles. The most common mismatched fibre phenotypes comprised fibres displaying coexpression of both fast MHCs when analysed by immunocytochemistry, but showing an mATPase profile similar to typical IIX fibres (moderate mATPase reaction after preincubation at pH 4.4). Considered altogether, the total mismatched fibres represented only 4.2% of the whole fast fibre population in the superficial region of the muscle, but their proportion increased to 15.6% and 38.4% in the middle and deep regions, respectively, of gluteus medius. It is concluded that a considerable number of hybrid fast MHC IIAX fibres are present in the gluteus medius of untrained horses, suggesting that equine type II fibres have probably been misclassified in

  19. Cancer cells become susceptible to natural killer cell killing after exposure to histone deacetylase inhibitors due to glycogen synthase kinase-3-dependent expression of MHC class I-related chain A and B

    DEFF Research Database (Denmark)

    Skov, Søren; Pedersen, Marianne Terndrup; Andresen, Lars

    2005-01-01

    We show that histone deacetylase (HDAC) inhibitors lead to functional expression of MHC class I-related chain A and B (MICA/B) on cancer cells, making them potent targets for natural killer (NK) cell-mediated killing through a NK group 2, member D (NKG2D) restricted mechanism. Blocking either...

  20. Diversity analysis of the immunoglobulin M heavy chain gene in Nile ...

    African Journals Online (AJOL)

    nu tom

    2015-07-22

    Jul 22, 2015 ... related industries and supply chains, such as hatcheries, feed manufacturers ... system has a high risk of disease outbreaks. The bulk of ...... immunoglobulin heavy-chain locus in zebrafish: identification and expression of a ...

  1. MHC class I ligation of human T cells activates the ZAP70 and p56lck tyrosine kinases, leads to an alternative phenotype of the TCR/CD3 zeta-chain, and induces apoptosis

    DEFF Research Database (Denmark)

    Skov, S; Bregenholt, S; Claesson, Mogens Helweg

    1997-01-01

    Cross-linking of MHC class I (MHC-I) molecules on human T cells induces signal-transduction events, including activation of tyrosine kinases, tyrosine phosphorylation of phospholipase C-gamma 1, and elevation of the intracellular free calcium concentration. In this study, we demonstrate...... that the ZAP70 tyrosine kinase is tyrosine phosphorylated in Jurkat T cells and in purified peripheral T cells after MHC-I ligation. The tyrosine-phosphorylated ZAP70 kinase exhibits a particular phenotype with low affinities for proteins at 21, 40, 60, and 120 kDa, proteins normally co-precipitated with ZAP70...... after TCR/CD3 stimulation. The phosphorylation of ZAP70 after MHC-I ligation was dependent on TCR/CD3 surface expression. One of the natural substrates for ZAP70 is the zeta-chain dimer of the TCR/CD3 complex. MHC-I cross-linking induces a phosphorylated zeta-protein that migrates as a dimer at 42 k...

  2. Prediction of antigenic epitopes and MHC binders of neurotoxin ...

    African Journals Online (AJOL)

    PRECIOUS

    2009-12-01

    Dec 1, 2009 ... scorpion chlorotoxin-like short-chain neurotoxins (SCNs). *Corresponding ... Protein sequence analysis. Here we ... MHC/peptide binding is a log-transformed value related to the IC50 values in nM ..... porter. Adducts of MHC and peptide complexes are the ligands for T cell receptors (TCR) (Table-1). MHC.

  3. The mRNA expression profile of metabolic genes relative to MHC isoform pattern in human skeletal muscles

    DEFF Research Database (Denmark)

    Plomgaard, Peter; Penkowa, Milena; Leick, Lotte

    2006-01-01

    The metabolic profile of rodent muscle is generally reflected in the myosin heavy chain (MHC) fiber-type composition. The present study was conducted to test the hypothesis that metabolic gene expression is not tightly coupled with MHC fiber-type composition for all genes in human skeletal muscle....... Triceps brachii, vastus lateralis quadriceps, and soleus muscle biopsies were obtained from normally physically active, healthy, young male volunteers, because these muscles are characterized by different fiber-type compositions. As expected, citrate synthase and 3-hydroxyacyl dehydrogenase activity...... of a broad range of metabolic genes. The triceps muscle had two- to fivefold higher MHC IIa, phosphofructokinase, and LDH A mRNA content and two- to fourfold lower MHC I, lipoprotein lipase, CD36, hormone-sensitive lipase, and LDH B and hexokinase II mRNA than vastus lateralis or soleus. Interestingly...

  4.  Variable fragments of heavy chain antibodies (VHHs: a new magic bullet molecule of medicine?

    Directory of Open Access Journals (Sweden)

    Dorota Smolarek

    2012-06-01

    Full Text Available  Serum of animals belonging to the Camelidae family (camels and llamas contains fully active antibodies that are naturally devoid of light chains. Variable domains derived from heavy chain antibodies (hcAb called VHHs or nanobodies™ can bind antigens as effectively as full-length antibodies and are easy to clone and express. Because of their potential, VHHs are being intensively studied as potential therapeutic, diagnostic and imaging tools. The paper reviews the molecular background of heavy chain antibodies and describes methods of obtaining recombinant fragments of heavy chain antibodies as well as their therapeutic, diagnostic and other applications.

  5. Statistical deconvolution of enthalpic energetic contributions to MHC-peptide binding affinity

    Directory of Open Access Journals (Sweden)

    Drew Michael GB

    2006-03-01

    Full Text Available Abstract Background MHC Class I molecules present antigenic peptides to cytotoxic T cells, which forms an integral part of the adaptive immune response. Peptides are bound within a groove formed by the MHC heavy chain. Previous approaches to MHC Class I-peptide binding prediction have largely concentrated on the peptide anchor residues located at the P2 and C-terminus positions. Results A large dataset comprising MHC-peptide structural complexes was created by re-modelling pre-determined x-ray crystallographic structures. Static energetic analysis, following energy minimisation, was performed on the dataset in order to characterise interactions between bound peptides and the MHC Class I molecule, partitioning the interactions within the groove into van der Waals, electrostatic and total non-bonded energy contributions. Conclusion The QSAR techniques of Genetic Function Approximation (GFA and Genetic Partial Least Squares (G/PLS algorithms were used to identify key interactions between the two molecules by comparing the calculated energy values with experimentally-determined BL50 data. Although the peptide termini binding interactions help ensure the stability of the MHC Class I-peptide complex, the central region of the peptide is also important in defining the specificity of the interaction. As thermodynamic studies indicate that peptide association and dissociation may be driven entropically, it may be necessary to incorporate entropic contributions into future calculations.

  6. Doxorubicin-conjugated bacteriophages carrying anti-MHC class I chain-related A for targeted cancer therapy in vitro

    Directory of Open Access Journals (Sweden)

    Phumyen A

    2014-11-01

    . Dox-phage was more efficient than free drugs in killing all the cell lines tested. The half maximal inhibitory concentration (IC50 values of Dox-phage were lower than those of free drugs at approximately 1.6–6 times depending on MICA expressions and the cell lines tested. Conclusion: Evidently, the application of 1-ethyl-3-[3-dimethylaminopropyl] carbodiimide chemistry is effective to conjugate doxorubicin and major coat protein of bacteriophages without destroying binding activity of MICA antibodies. Dox-carrying bacteriophages targeting MICA have been successfully developed and may enable a broad range of applications in cancer-targeting chemotherapy. Keywords: MHC class I chain–related A (MICA, phage display, doxorubicin, targeted therapy

  7. Characterization of the interaction between the heavy and light chains of bovine factor Va.

    Science.gov (United States)

    Walker, F J

    1992-10-05

    Bovine factor Va has been previously been shown to consist of heavy (M(r) = 94,000) and light chains (M(r) = 81,000), that interact in a manner dependent upon the presence of either calcium or manganese ions. In an attempt to understand the mechanism of subunit interaction we have studied the effects of temperature and ions on factor Va stability. The rates of formation of factor Va from isolated chains and dissociation were temperature-dependent with an energy of activation of 6.2 and 1.3 kcal mol-1, respectively. The yield of factor Va from isolated chains was inversely related to the amount of time the chains were incubated at 4 degrees C. Incubation of individual chains revealed that the heavy chain is cold-labile, an effect that is reversible. Manganese ion was observed to prevent the conversion to the inactive form. High salt tends to stabilize the two-chain structure of factor Va, but is inhibitory to its formation from isolated chains. High concentrations of either manganese or calcium ions also inhibited reconstitution of activity. The light chain, in particular, was sensitive to the presence of manganese or calcium ion. Heavy chain that had been cleaved by activated protein C had a weakened interaction with the light chain, and the resulting complex had no procoagulant activity. Cooling of the heavy chain to 4 degrees C enhanced its intrinsic fluorescence. Manganese ion prevented some of this enhancement. The heavy chain fluorescence returned to the room temperature value with a half-life of approximately 10 min. In the presence of manganese ion relaxation was accelerated. The intrinsic fluorescence of activated protein C-cleaved heavy chain was not increased when the temperature was decreased. These data suggest that the heavy chain can exist in two forms. Elevated temperature converts it to a form that can bind ions and have a productive interaction with the light chain. However, conditions that prevent the heavy chain from combining with the light

  8. Characterization of human cardiac myosin heavy chain genes

    International Nuclear Information System (INIS)

    Yamauchi-Takihara, K.; Sole, M.J.; Liew, J.; Ing, D.; Liew, C.C.

    1989-01-01

    The authors have isolated and analyzed the structure of the genes coding for the α and β forms of the human cardiac myosin heavy chain (MYHC). Detailed analysis of four overlapping MYHC genomic clones shows that the α-MYHC and β-MYHC genes constitute a total length of 51 kilobases and are tandemly linked. The β-MYHC-encoding gene, predominantly expressed in the normal human ventricle and also in slow-twitch skeletal muscle, is located 4.5 kilobases upstream of the α-MYHC-encoding gene, which is predominantly expressed in normal human atrium. The authors have determined the nucleotide sequences of the β form of the MYHC gene, which is 100% homologous to the cardiac MYHC cDNA clone (pHMC3). It is unlikely that the divergence of a few nucleotide sequences from the cardiac β-MYHC cDNA clone (pHMC3) reported in a MYHC cDNA clone (PSMHCZ) from skeletal muscle is due to a splicing mechanism. This finding suggests that the same β form of the cardiac MYHC gene is expressed in both ventricular and slow-twitch skeletal muscle. The promoter regions of both α- and β-MYHC genes, as well as the first four coding regions in the respective genes, have also been sequenced. The sequences in the 5'-flanking region of the α- and β-MYHC-encoding genes diverge extensively from one another, suggesting that expression of the α- and β-MYHC genes is independently regulated

  9. Porcine circovirus type 2 ORF4 protein binds heavy chain ferritin

    Indian Academy of Sciences (India)

    Porcine circovirus type 2 ORF4 protein binds heavy chain ferritin. Qizhuang Lv Kangkang Guo Tao Wang ... Keywords. Cellular protein; FHC; ORF4 protein; porcine circovirus type 2 (PCV2); yeast two-hybrid ... Journal of Biosciences | News ...

  10. Serial cerebrospinal fluid neurofilament heavy chain levels in severe Guillain-Barre syndrome

    NARCIS (Netherlands)

    Dujmovic, I.; Lunn, M.P.; Reilly, M.M.; Petzold, A.

    2013-01-01

    Introduction: Proximal axonotmesis results in the release of neurofilament (Nf) proteins into the cerebrospinal fluid (CSF) in patients with Guillain-Barré syndrome (GBS). High CSF levels of the phosphorylated form of Nf-heavy chain (NfH

  11. The motion planning problem and exponential stabilization of a heavy chain. Part II

    OpenAIRE

    Piotr Grabowski

    2008-01-01

    This is the second part of paper [P. Grabowski, The motion planning problem and exponential stabilization of a heavy chain. Part I, to appear in International Journal of Control], where a model of a heavy chain system with a punctual load (tip mass) in the form of a system of partial differential equations was interpreted as an abstract semigroup system and then analysed on a Hilbert state space. In particular, in [P. Grabowski, The motion planning problem and exponential stabilization of a h...

  12. Tracing heavy metals in 'swine manure - maggot - chicken' production chain.

    Science.gov (United States)

    Wang, Wanqiang; Zhang, Wenjuan; Wang, Xiaoping; Lei, Chaoliang; Tang, Rui; Zhang, Feng; Yang, Qizhi; Zhu, Fen

    2017-08-21

    With the development of large-scale livestock farming, manure pollution has drawn much attention. Conversion by insects is a rapid and cost-effective new method for manure management. Swine manure conversion with maggots (Musca domestica larvae) has developed, and the harvested maggots are often used as animal feed. However, the flow of heavy metals from manure to downstream processes cannot be ignored, and therefore, heavy metal content was measured in untreated raw manure, maggot-treated manure, harvested maggots and maggot-eating chickens (chest muscle and liver) to evaluate potential heavy metal risks. The levels of zinc, copper, chromium, selenium, cadmium and lead had significant differences between untreated raw manure and maggot-treated manure. The concentrations of all detected heavy metals, except for cadmium and selenium, in maggots met the limits established by the feed or feed additive standards of many countries. The bioaccumulation factor (BAF) of heavy metals decreased with the increase of the maggot instar, indicating that heavy metals were discharged from the bodies of maggots with the growth of maggots. Also, the contents of overall heavy metals in chickens fed harvested maggots met the standards for food. In conclusion, regarding heavy metals, it is eco-safe to use maggots in manure management.

  13. MHC motif viewer

    DEFF Research Database (Denmark)

    Rapin, Nicolas Philippe Jean-Pierre; Hoof, Ilka; Lund, Ole

    2008-01-01

    . Algorithms that predict which peptides MHC molecules bind have recently been developed and cover many different alleles, but the utility of these algorithms is hampered by the lack of tools for browsing and comparing the specificity of these molecules. We have, therefore, developed a web server, MHC motif....... A special viewing feature, MHC fight, allows for display of the specificity of two different MHC molecules side by side. We show how the web server can be used to discover and display surprising similarities as well as differences between MHC molecules within and between different species. The MHC motif...

  14. Role of cyclic AMP sensor Epac1 in masseter muscle hypertrophy and myosin heavy chain transition induced by β2-adrenoceptor stimulation.

    Science.gov (United States)

    Ohnuki, Yoshiki; Umeki, Daisuke; Mototani, Yasumasa; Jin, Huiling; Cai, Wenqian; Shiozawa, Kouichi; Suita, Kenji; Saeki, Yasutake; Fujita, Takayuki; Ishikawa, Yoshihiro; Okumura, Satoshi

    2014-12-15

    The predominant isoform of β-adrenoceptor (β-AR) in skeletal muscle is β2-AR and that in the cardiac muscle is β1-AR. We have reported that Epac1 (exchange protein directly activated by cAMP 1), a new protein kinase A-independent cAMP sensor, does not affect cardiac hypertrophy in response to pressure overload or chronic isoproterenol (isoprenaline) infusion. However, the role of Epac1 in skeletal muscle hypertrophy remains poorly understood. We thus examined the effect of disruption of Epac1, the major Epac isoform in skeletal muscle, on masseter muscle hypertrophy induced by chronic β2-AR stimulation with clenbuterol (CB) in Epac1-null mice (Epac1KO). The masseter muscle weight/tibial length ratio was similar in wild-type (WT) and Epac1KO at baseline and was significantly increased in WT after CB infusion, but this increase was suppressed in Epac1KO. CB treatment significantly increased the proportion of myosin heavy chain (MHC) IIb at the expense of that of MHC IId/x in both WT and Epac1KO, indicating that Epac1 did not mediate the CB-induced MHC isoform transition towards the faster isoform. The mechanism of suppression of CB-mediated hypertrophy in Epac1KO is considered to involve decreased activation of Akt signalling. In addition, CB-induced histone deacetylase 4 (HDAC4) phosphorylation on serine 246 mediated by calmodulin kinase II (CaMKII), which plays a role in skeletal muscle hypertrophy, was suppressed in Epac1KO. Our findings suggest that Epac1 plays a role in β2-AR-mediated masseter muscle hypertrophy, probably through activation of both Akt signalling and CaMKII/HDAC4 signalling. © 2014 The Authors. The Journal of Physiology © 2014 The Physiological Society.

  15. Acquired cutis laxa associated with light and heavy chain deposition disease

    Directory of Open Access Journals (Sweden)

    Reena A Majithia

    2018-01-01

    Full Text Available Acquired cutis laxa (ACL is a rare connective tissue disorder characterized by pendulous and coarsely wrinkled skin. There have been few cases of its association to monoclonal immunoglobulin deposition disease (MIDD, which constitutes the light chain (LCDD, heavy chain (HCDD, and light and heavy chain (LHCDD deposition disease. MIDD predominantly involves the kidney. Skin is the next common organ to be affected by HCDD, which presents as ACL. We report the case of a 40-year-old male who presented with ACL associated with LHCDD. The clinical features of ACL in the present case appeared prior to the development of clinical features related to LHCDD.

  16. Excessive amounts of mu heavy chain block B-cell development.

    Science.gov (United States)

    Zhu, Lingqiao; Chang, Cheong-Hee; Dunnick, Wesley

    2011-09-01

    Antigen-independent B-cell development occurs in several stages that depend on the expression of Ig heavy and light chain. We identified a line of mice that lacked mature B cells in the spleen. This mouse line carried approximately 11 copies of a transgene of the murine heavy chain constant region locus, and B-lineage cells expressed excessive amounts of the intracellular μ heavy chain. B-cell development failed in the bone marrow at the pro/pre B-cell transition, and examination of other lines with various copy numbers of the same transgene suggested that deficiencies in B-cell development increased with increased transgene copy number. Expression of a transgenic (Tg) light chain along with the Tg μ heavy chain led to minimal rescue of B-cell development in the bone marrow and B cells in the spleen. There are several potential mechanisms for the death of pro/pre B cells as a consequence of excess heavy chain expression.

  17. The association of heavy and light chain variable domains in antibodies: implications for antigen specificity.

    KAUST Repository

    Chailyan, Anna

    2011-06-28

    The antigen-binding site of immunoglobulins is formed by six regions, three from the light and three from the heavy chain variable domains, which, on association of the two chains, form the conventional antigen-binding site of the antibody. The mode of interaction between the heavy and light chain variable domains affects the relative position of the antigen-binding loops and therefore has an effect on the overall conformation of the binding site. In this article, we analyze the structure of the interface between the heavy and light chain variable domains and show that there are essentially two different modes for their interaction that can be identified by the presence of key amino acids in specific positions of the antibody sequences. We also show that the different packing modes are related to the type of recognized antigen.

  18. The properties of the single chicken MHC classical class II alpha chain (B-LA) gene indicate an ancient origin for the DR/E-like isotype of class II molecules

    DEFF Research Database (Denmark)

    Salomonsen, Jan; Marston, Denise; Avila, David

    2003-01-01

    for the cloning and sequencing of the cDNA. We found only one class II alpha chain transcript, which bears the major features of a classical class II alpha sequence, including the critical peptide-binding residues. The chicken sequence is more similar to human DR than to the DQ, DP, DO or DM isotypes, most...... the mammalian DR and E isotypes in three properties: the presence of the critical peptide-binding residues, the low level of polymorphism and sequence diversity, and the recombinational separation from the class II beta chain genes. These results indicate that the sequence features of this lineage are both......In mammals, there are MHC class II molecules with distinctive sequence features, such as the classical isotypes DR, DQ and DP. These particular isotypes have not been reported in non-mammalian vertebrates. We have isolated the class II (B-L) alpha chain from outbred chickens as the basis...

  19. Heavy subgraph pairs for traceability of block-chains

    NARCIS (Netherlands)

    Li, Binlong; Li, Binlong; Broersma, Haitze J.; Zhang, Shenggui

    2014-01-01

    A graph is called traceable if it contains a Hamilton path, i.e., a path containing all its vertices. Let G be a graph on n vertices. We say that an induced subgraph of G is o-1-heavy if it contains two nonadjacent vertices which satisfy an Ore-type degree condition for traceability, i.e., with

  20. The association of heavy and light chain variable domains in antibodies: implications for antigen specificity.

    KAUST Repository

    Chailyan, Anna; Marcatili, Paolo; Tramontano, Anna

    2011-01-01

    of interaction between the heavy and light chain variable domains affects the relative position of the antigen-binding loops and therefore has an effect on the overall conformation of the binding site. In this article, we analyze the structure of the interface

  1. Expression and production of llama variable heavy-chain antibody fragments (VHHs) by Aspergillus awamori

    NARCIS (Netherlands)

    Joosten, V.; Gouka, R.J.; Hondel, C.A.M.J.J. van den; Verrips, C.T.; Lokman, B.C.

    2005-01-01

    We report the expression and production of llama variable heavy-chain antibody fragments (VHHs) by Aspergillus awamori. Fragments encoding VHHs were cloned in a suitable Aspergillus expression vector and transformants secreting VHH fragments were analysed for integrated gene copy-numbers, mRNA

  2. Improved production and function of llama heavy chain antibody fragments by molecular evolution

    NARCIS (Netherlands)

    Linden, van der R.H.; Geus, de B.; Frenken, G.J.; Peters, H.; Verrips, C.T.

    2000-01-01

    The aim of this study was to improve production level of llama heavy chain antibody fragments (V (HH)) in Saccharomyces cerevisiae while retaining functional characteristics. For this purpose, the DNA shuffling technique was used on llama V (HH) fragments specific for the azo-dye reactive red-6. In

  3. Expression of porcine myosin heavy chain 1 gene in Berkshire loins ...

    African Journals Online (AJOL)

    Expression of porcine myosin heavy chain 1 gene in Berkshire loins with a high pH24 value. Jin Hun Kang, Woo Young Bang, Eun Jung Kwon, Yong Hwa Lee, Da Hye Park, Eun Seok Cho, Min Ji Kim, Jong-Soon Choi, Hwa Chun Park, Beom Young Park, Chul Wook Kim ...

  4. Determination of allergen specificity by heavy chains in grass pollen allergen-specific IgE antibodies.

    Science.gov (United States)

    Gadermaier, Elisabeth; Flicker, Sabine; Lupinek, Christian; Steinberger, Peter; Valenta, Rudolf

    2013-04-01

    Affinity and clonality of allergen-specific IgE antibodies are important determinants for the magnitude of IgE-mediated allergic inflammation. We sought to analyze the contribution of heavy and light chains of human allergen-specific IgE antibodies for allergen specificity and to test whether promiscuous pairing of heavy and light chains with different allergen specificity allows binding and might affect affinity. Ten IgE Fabs specific for 3 non-cross-reactive major timothy grass pollen allergens (Phl p 1, Phl p 2, and Phl p 5) obtained by means of combinatorial cloning from patients with grass pollen allergy were used to construct stable recombinant single chain variable fragments (ScFvs) representing the original Fabs and shuffled ScFvs in which heavy chains were recombined with light chains from IgE Fabs with specificity for other allergens by using the pCANTAB 5 E expression system. Possible ancestor genes for the heavy chain and light chain variable region-encoding genes were determined by using sequence comparison with the ImMunoGeneTics database, and their chromosomal locations were determined. Recombinant ScFvs were tested for allergen specificity and epitope recognition by means of direct and sandwich ELISA, and affinity by using surface plasmon resonance experiments. The shuffling experiments demonstrate that promiscuous pairing of heavy and light chains is possible and maintains allergen specificity, which is mainly determined by the heavy chains. ScFvs consisting of different heavy and light chains exhibited different affinities and even epitope specificity for the corresponding allergen. Our results indicate that allergen specificity of allergen-specific IgE is mainly determined by the heavy chains. Different heavy and light chain pairings in allergen-specific IgE antibodies affect affinity and epitope specificity and thus might influence clinical reactivity to allergens. Copyright © 2012 American Academy of Allergy, Asthma & Immunology. Published by

  5. Detection of clonal immunoglobulin heavy chain gene rearrangements by the polymerase chain reaction and capillary gel electrophoresis.

    Science.gov (United States)

    Fan, Hongxin; Robetorye, Ryan S

    2013-01-01

    Although well-established diagnostic criteria exist for mature B-cell neoplasms, a definitive diagnosis of a B-cell lymphoproliferative disorder cannot always be obtained using more conventional techniques such as flow cytometric immunophenotyping, conventional cytogenetics, fluorescence in situ hybridization, or immunohistochemistry. However, because B-cell malignancies contain identically rearranged immunoglobulin heavy chain genes, the polymerase chain reaction (PCR) can be a fast, convenient, and dependable option to identify clonal B-cell processes. This chapter describes the use of PCR and capillary electrophoresis to identify clonal immunoglobulin heavy chain (IGH) variable and joining region (VH-JH) gene rearrangements (IGH VH-JH PCR) using a commercially available method employing multiple multiplex PCR tubes that was originally developed as the result of a large European BIOMED-2 collaborative study (Invivoscribe Technologies). The core protocol involves the use of three separate master mix tubes that target the conserved framework (FR1, FR2, and FR3) and joining (J) regions of the IGH gene. Analysis of these three framework regions can detect approximately 88% of clonal IGH gene rearrangements.

  6. Shark Ig light chain junctions are as diverse as in heavy chains.

    Science.gov (United States)

    Fleurant, Marshall; Changchien, Lily; Chen, Chin-Tung; Flajnik, Martin F; Hsu, Ellen

    2004-11-01

    We have characterized a small family of four genes encoding one of the three nurse shark Ig L chain isotypes, called NS5. All NS5 cDNA sequences are encoded by three loci, of which two are organized as conventional clusters, each consisting of a V and J gene segment that can recombine and one C region exon; the third contains a germline-joined VJ in-frame and the fourth locus is a pseudogene. This is the second nurse shark L chain type where both germline-joined and split V-J organizations have been found. Since there are only two rearranging Ig loci, it was possible for the first time to examine junctional diversity in defined fish Ig genes, comparing productive vs nonproductive rearrangements. N region addition was found to be considerably more extensive in length and in frequency than any other vertebrate L chain so far reported and rivals that in H chain. We put forth the speculation that the unprecedented efficiency of N region addition (87-93% of NS5 sequences) may be a result not only of simultaneous H and L chain rearrangement in the shark but also of processing events that afford greater accessibility of the V or J gene coding ends to terminal deoxynucleotidyltransferase.

  7. Heavy and Light chain amyloidosois presenting as complete heart block: A rare presentation of a rare disease.

    Science.gov (United States)

    Priyamvada, P S; Morkhandikar, S; Srinivas, B H; Parameswaran, S

    2015-01-01

    Amyloidosis is an uncommon disease characterized by deposition of proteinaceous material in the extracellular matrix, which results from abnormal protein folding. Even though more than 25 precursor proteins are identified, majority of systemic amyloidosis results from deposition of abnormal immunoglobulin (Ig) light chains. In heavy chain amyloidosis (AH), deposits are derived from both heavy chain alone, whereas in heavy and light chain amyloidosis (AHL), the deposits are derived from Ig heavy chains and light chains. Both AH and AHL are extremely rare diseases. Here, we report an unusual presentation of IgG (lambda) AHL amyloidosis in the background of multiple myeloma, where the initial clinical presentation was complete heart block, which preceded the definitive diagnosis by 18 months.

  8. Heavy and Light chain amyloidosois presenting as complete heart block: A rare presentation of a rare disease

    Directory of Open Access Journals (Sweden)

    P S Priyamvada

    2015-01-01

    Full Text Available Amyloidosis is an uncommon disease characterized by deposition of proteinaceous material in the extracellular matrix, which results from abnormal protein folding. Even though more than 25 precursor proteins are identified, majority of systemic amyloidosis results from deposition of abnormal immunoglobulin (Ig light chains. In heavy chain amyloidosis (AH, deposits are derived from both heavy chain alone, whereas in heavy and light chain amyloidosis (AHL, the deposits are derived from Ig heavy chains and light chains. Both AH and AHL are extremely rare diseases. Here, we report an unusual presentation of IgG (lambda AHL amyloidosis in the background of multiple myeloma, where the initial clinical presentation was complete heart block, which preceded the definitive diagnosis by 18 months.

  9. Expression, refolding and crystallization of murine MHC class I H-2Db in complex with human β2-microglobulin

    International Nuclear Information System (INIS)

    Sandalova, Tatyana; Michaëlsson, Jakob; Harris, Robert A.; Ljunggren, Hans-Gustaf; Kärre, Klas; Schneider, Gunter; Achour, Adnane

    2005-01-01

    Mouse MHC class I H-2Db in complex with human β2m and the LCMV-derived peptide gp33 has been produced and crystallized. Resolution of the structure of this complex combined with the structural comparison with the previously solved crystal structure of H-2Db/mβ2m/gp33 should lead to a better understanding of how the β2m subunit affects the overall conformation of MHC complexes as well as the stability of the presented peptides. β 2 -Microglobulin (β 2 m) is non-covalently linked to the major histocompatibility (MHC) class I heavy chain and interacts with CD8 and Ly49 receptors. Murine MHC class I can bind human β 2 m (hβ 2 m) and such hybrid molecules are often used in structural and functional studies. The replacement of mouse β 2 m (mβ 2 m) by hβ 2 m has important functional consequences for MHC class I complex stability and specificity, but the structural basis for this is unknown. To investigate the impact of species-specific β 2 m subunits on MHC class I conformation, murine MHC class I H-2D b in complex with hβ 2 m and the peptide gp33 derived from lymphocytic choriomeningitis virus (LCMV) has been expressed, refolded in vitro and crystallized. Crystals containing two complexes per asymmetric unit and belonging to the space group P2 1 , with unit-cell parameters a = 68.1, b = 65.2, c = 101.9 Å, β = 102.4°, were obtained

  10. Nanobodies and Nanobody-Based Human Heavy Chain Antibodies As Antitumor Therapeutics

    Directory of Open Access Journals (Sweden)

    Peter Bannas

    2017-11-01

    Full Text Available Monoclonal antibodies have revolutionized cancer therapy. However, delivery to tumor cells in vivo is hampered by the large size (150 kDa of conventional antibodies. The minimal target recognition module of a conventional antibody is composed of two non-covalently associated variable domains (VH and VL. The proper orientation of these domains is mediated by their hydrophobic interface and is stabilized by their linkage to disulfide-linked constant domains (CH1 and CL. VH and VL domains can be fused via a genetic linker into a single-chain variable fragment (scFv. scFv modules in turn can be fused to one another, e.g., to generate a bispecific T-cell engager, or they can be fused in various orientations to antibody hinge and Fc domains to generate bi- and multispecific antibodies. However, the inherent hydrophobic interaction of VH and VL domains limits the stability and solubility of engineered antibodies, often causing aggregation and/or mispairing of V-domains. Nanobodies (15 kDa and nanobody-based human heavy chain antibodies (75 kDa can overcome these limitations. Camelids naturally produce antibodies composed only of heavy chains in which the target recognition module is composed of a single variable domain (VHH or Nb. Advantageous features of nanobodies include their small size, high solubility, high stability, and excellent tissue penetration in vivo. Nanobodies can readily be linked genetically to Fc-domains, other nanobodies, peptide tags, or toxins and can be conjugated chemically at a specific site to drugs, radionuclides, photosensitizers, and nanoparticles. These properties make them particularly suited for specific and efficient targeting of tumors in vivo. Chimeric nanobody-heavy chain antibodies combine advantageous features of nanobodies and human Fc domains in about half the size of a conventional antibody. In this review, we discuss recent developments and perspectives for applications of nanobodies and nanobody

  11. Nanobodies and Nanobody-Based Human Heavy Chain Antibodies As Antitumor Therapeutics.

    Science.gov (United States)

    Bannas, Peter; Hambach, Julia; Koch-Nolte, Friedrich

    2017-01-01

    Monoclonal antibodies have revolutionized cancer therapy. However, delivery to tumor cells in vivo is hampered by the large size (150 kDa) of conventional antibodies. The minimal target recognition module of a conventional antibody is composed of two non-covalently associated variable domains (VH and VL). The proper orientation of these domains is mediated by their hydrophobic interface and is stabilized by their linkage to disulfide-linked constant domains (CH1 and CL). VH and VL domains can be fused via a genetic linker into a single-chain variable fragment (scFv). scFv modules in turn can be fused to one another, e.g., to generate a bispecific T-cell engager, or they can be fused in various orientations to antibody hinge and Fc domains to generate bi- and multispecific antibodies. However, the inherent hydrophobic interaction of VH and VL domains limits the stability and solubility of engineered antibodies, often causing aggregation and/or mispairing of V-domains. Nanobodies (15 kDa) and nanobody-based human heavy chain antibodies (75 kDa) can overcome these limitations. Camelids naturally produce antibodies composed only of heavy chains in which the target recognition module is composed of a single variable domain (VHH or Nb). Advantageous features of nanobodies include their small size, high solubility, high stability, and excellent tissue penetration in vivo . Nanobodies can readily be linked genetically to Fc-domains, other nanobodies, peptide tags, or toxins and can be conjugated chemically at a specific site to drugs, radionuclides, photosensitizers, and nanoparticles. These properties make them particularly suited for specific and efficient targeting of tumors in vivo . Chimeric nanobody-heavy chain antibodies combine advantageous features of nanobodies and human Fc domains in about half the size of a conventional antibody. In this review, we discuss recent developments and perspectives for applications of nanobodies and nanobody-based human heavy

  12. Clathrin Heavy Chain Is Important for Viability, Oviposition, Embryogenesis and, Possibly, Systemic RNAi Response in the Predatory Mite Metaseiulus occidentalis

    Science.gov (United States)

    Wu, Ke; Hoy, Marjorie A.

    2014-01-01

    Clathrin heavy chain has been shown to be important for viability, embryogenesis, and RNA interference (RNAi) in arthropods such as Drosophila melanogaster. However, the functional roles of clathrin heavy chain in chelicerate arthropods, such as the predatory mite Metaseiulus occidentalis, remain unknown. We previously showed that dsRNA ingestion, followed by feeding on spider mites, induced systemic and robust RNAi in M. occidentalis females. In the current study, we performed a loss-of-function analysis of the clathrin heavy chain gene in M. occidentalis using RNAi. We showed that ingestion of clathrin heavy chain dsRNA by M. occidentalis females resulted in gene knockdown and reduced longevity. In addition, clathrin heavy chain dsRNA treatment almost completely abolished oviposition by M. occidentalis females and the few eggs produced did not hatch. Finally, we demonstrated that clathrin heavy chain gene knockdown in M. occidentalis females significantly reduced a subsequent RNAi response induced by ingestion of cathepsin L dsRNA. The last finding suggests that clathrin heavy chain may be involved in systemic RNAi responses mediated by orally delivered dsRNAs in M. occidentalis. PMID:25329675

  13. Early Bronchus-Associated Lymphoid Tissue Lymphoma Diagnosed with Immunoglobulin Heavy Chain Molecular Testing

    Directory of Open Access Journals (Sweden)

    Pen Li

    2016-01-01

    Full Text Available When extranodal marginal zone B-cell lymphoma of mucosa associated lymphoid tissue (MALT, a low grade B-cell lymphoma, arises in the lung it is referred to as bronchus-associated lymphoid tissue (BALT lymphoma. We describe a patient with a history of Sjögren’s syndrome and rheumatoid arthritis with dyspnea and imaging consistent with lymphoid interstitial pneumonia (LIP. However, while histology and immunohistochemistry lacked definitive features of a lymphoma, immunoglobulin heavy chain (IgH polymerase chain reaction testing demonstrated B-cell monoclonality, consistent with an early BALT lymphoma.

  14. Use of bortezomib in heavy-chain deposition disease: a report of 3 cases.

    Science.gov (United States)

    Patel, Kinjal; Dillon, John J; Leung, Nelson; Bomback, Andrew S; Appel, Gerald B; D'Agati, Vivette; Canetta, Pietro A

    2014-07-01

    Heavy-chain deposition disease (HCDD) is a rare complication of plasma cell dyscrasia in which monoclonal heavy chains deposit in glomerular and tubular basement membranes of the kidney. Clinical and pathologic features of HCDD have been well described in case reports and series, but evidence supporting specific therapies is sparse. Historically, the disease has had a poor prognosis, intensifying the need to clarify optimal treatments. We describe 3 cases of HCDD with biopsy-proven glomerular involvement, severe nephrotic syndrome, and decline in kidney function that were treated successfully with bortezomib, a proteasome inhibitor. None of these patients had multiple myeloma. In all cases, bortezomib-based therapy resulted in sustained resolution of nephrotic syndrome and improvement in kidney function. All 3 patients developed peripheral neuropathy; otherwise, treatment was well tolerated. To our knowledge, this is the first description of the clinical effectiveness of bortezomib against HCDD. Copyright © 2014 National Kidney Foundation, Inc. Published by Elsevier Inc. All rights reserved.

  15. Porous silicon biosensor for detection of variable domain of heavy-chain of HCAb antibody

    Science.gov (United States)

    Zhang, Hong-yan; Lü, Xiao-yi; Jia, Zhen-hong; Li, Jiang-wei; Zhang, Fu-chun

    2012-03-01

    In this paper, we produce porous silicon (PSi) by electrochemical etching, and it is the first time to evaluate the performance of label-free porous silicon biosensor for detection of variable domain of heavy chain of heavy-chain antibody (VHH). The binding of hen egg white lysozyme (HEWL) and VHH causes a red shift in the reflection spectrum of the biosensor. The red shift is proportional to the VHH concentration in the range from 14 g·ml-1 to 30 g·ml-1 with a detection limit of 0.648 ng·ml-1. The research is useful for the development of label-free biosensor applied in the rapid and sensitive determination of small molecules.

  16. Primordial linkage of β2-microglobulin to the MHC.

    Science.gov (United States)

    Ohta, Yuko; Shiina, Takashi; Lohr, Rebecca L; Hosomichi, Kazuyoshi; Pollin, Toni I; Heist, Edward J; Suzuki, Shingo; Inoko, Hidetoshi; Flajnik, Martin F

    2011-03-15

    β2-Microglobulin (β2M) is believed to have arisen in a basal jawed vertebrate (gnathostome) and is the essential L chain that associates with most MHC class I molecules. It contains a distinctive molecular structure called a constant-1 Ig superfamily domain, which is shared with other adaptive immune molecules including MHC class I and class II. Despite its structural similarity to class I and class II and its conserved function, β2M is encoded outside the MHC in all examined species from bony fish to mammals, but it is assumed to have translocated from its original location within the MHC early in gnathostome evolution. We screened a nurse shark bacterial artificial chromosome library and isolated clones containing β2M genes. A gene present in the MHC of all other vertebrates (ring3) was found in the bacterial artificial chromosome clone, and the close linkage of ring3 and β2M to MHC class I and class II genes was determined by single-strand conformational polymorphism and allele-specific PCR. This study satisfies the long-held conjecture that β2M was linked to the primordial MHC (Ur MHC); furthermore, the apparent stability of the shark genome may yield other genes predicted to have had a primordial association with the MHC specifically and with immunity in general.

  17. Homologous recombination in hybridoma cells: heavy chain chimeric antibody produced by gene targeting.

    OpenAIRE

    Fell, H P; Yarnold, S; Hellström, I; Hellström, K E; Folger, K R

    1989-01-01

    We demonstrate that murine myeloma cells can efficiently mediate homologous recombination. The murine myeloma cell line J558L was shown to appropriately recombine two transfected DNA molecules in approximately 30% of cells that received and integrated intact copies of both molecules. This activity was then exploited to direct major reconstructions of an endogenous locus within a hybridoma cell line. Production of antigen-specific chimeric heavy chain was achieved by targeting the human IgG1 h...

  18. Distinctive CD8+ T cell and MHC class I signatures in polycythemia vera patients.

    Science.gov (United States)

    Cardoso, Elsa M; Esgalhado, André J; Patrão, Luís; Santos, Mónica; Neves, Vasco Pinto; Martinez, Jorge; Patto, Maria Assunção Vaz; Silva, Helena; Arosa, Fernando A

    2018-05-22

    Polycythemia vera (PV) is a myeloproliferative neoplasm characterized by overproduction of red blood cells. We have performed a comprehensive characterization of blood immune cells for expression of naïve and memory receptors as well as β 2 m-associated and β 2 m-free MHC class I heavy chains, also known as closed and open conformers, respectively, in PV patients and age-matched controls (CTR). We show that the peripheral CD3 + CD8 + T cell pool in PV patients is clearly divided into two discrete populations, a more granular CD3 + CD8 high T cell population enriched in effector-memory CD45RA + T cells (CD8 + TEMRA) when compared to CTR (P e., CD3 + CD8 int CD28 int . While the percentage of CD3 + CD8 int TN cells correlated positively with the number of erythrocytes, the percentage of CD3 + CD8 int TEMRA correlated negatively with the number of platelets. Finally, we report that PV patients' lymphocytes and monocytes display lower levels of closed (W6/32 + ) MHC-I conformers at the cell surface while exhibiting increased amounts of open (HC-10 + ) MHC-I conformers. The implications of this distinctive immune signature are discussed.

  19. MHC class I phenotype and function of human beta 2-microglobulin transgenic murine lymphocytes

    DEFF Research Database (Denmark)

    Bjerager, L; Pedersen, L O; Bregenholt, S

    1996-01-01

    . Based on data from cellular binding studies, Scatchard analyses and flow cytometry, it is concluded that exogenous h beta 2m does not bind to hybrid MHC class I (MHC-I) molecules composed of mouse heavy chain/h beta 2m molecules expressed on lymphocytes of transgenic mice. Immunoprecipitation and SDS......-PAGE analysis of metabolically labelled normal C57BL/6 lymph node cells showed binding of exogenous h beta 2m to MHC-I, in particular, to the H-2Db molecule through an exchange with endogenous mouse beta 2m. In contrast to normal H-2Db molecules, hybrid H-2Db expressed on the surface of transgenic lymphocytes...... binds radiolabelled peptide in the absence of exogenous added h beta 2m suggesting that a stable fraction of hybrid H-2Db molecules is empty or contain peptides with very low affinity. In a one-way allogenic mixed lymphocyte culture, transgenic splenocytes were found to be far less stimulatory than...

  20. Antibody Heavy Chain Variable Domains of Different Germline Gene Origins Diversify through Different Paths

    Directory of Open Access Journals (Sweden)

    Ufuk Kirik

    2017-11-01

    Full Text Available B cells produce antibodies, key effector molecules in health and disease. They mature their properties, including their affinity for antigen, through hypermutation events; processes that involve, e.g., base substitution, codon insertion and deletion, often in association with an isotype switch. Investigations of antibody evolution define modes whereby particular antibody responses are able to form, and such studies provide insight important for instance for development of efficient vaccines. Antibody evolution is also used in vitro for the design of antibodies with improved properties. To better understand the basic concepts of antibody evolution, we analyzed the mutational paths, both in terms of amino acid substitution and insertions and deletions, taken by antibodies of the IgG isotype. The analysis focused on the evolution of the heavy chain variable domain of sets of antibodies, each with an origin in 1 of 11 different germline genes representing six human heavy chain germline gene subgroups. Investigated genes were isolated from cells of human bone marrow, a major site of antibody production, and characterized by next-generation sequencing and an in-house bioinformatics pipeline. Apart from substitutions within the complementarity determining regions, multiple framework residues including those in protein cores were targets of extensive diversification. Diversity, both in terms of substitutions, and insertions and deletions, in antibodies is focused to different positions in the sequence in a germline gene-unique manner. Altogether, our findings create a framework for understanding patterns of evolution of antibodies from defined germline genes.

  1. Direct photoaffinity labeling by nucleotides of the apparent catalytic site on the heavy chains of smooth muscle and Acanthamoeba myosins

    International Nuclear Information System (INIS)

    Maruta, H.; Korn, E.D.

    1981-01-01

    The heavy chains of Acanthamoeba myosins, IA, IB and II, turkey gizzard myosin, and rabbit skeletal muscle myosin subfragment-1 were specifically labeled by radioactive ATP, ADP, and UTP, each of which is a substrate or product of myosin ATPase activity, when irradiated with uv light at 0 0 C. With UTP, as much as 0.45 mol/mol of Acanthamoeba myosin IA heavy chain and 1 mol/mol of turkey gizzard myosin heavy chain was incorporated. Evidence that the ligands were associated with the catalytic site included the observations that reaction occurred only with nucleotides that are substrates or products of the ATPase activity; that the reaction was blocked by pyrophosphate which is an inhibitor of the ATPase activity; that ATP was bound as ADP; and that label was probably restricted to a single peptide following limited subtilisin proteolysis of labeled Acanthamoeba myosin IA heavy chain and extensive cleavage with CNBr and trypsin of labeled turkey gizzard myosin heavy chain

  2. MHC Class I Chain-Related Gene A Polymorphisms and Linkage Disequilibrium with HLA-B and HLA-C Alleles in Ocular Toxoplasmosis

    Science.gov (United States)

    Ayo, Christiane Maria; Camargo, Ana Vitória da Silveira; Frederico, Fábio Batista; Siqueira, Rubens Camargo; Previato, Mariana; Murata, Fernando Henrique Antunes; Silveira-Carvalho, Aparecida Perpétuo; Barbosa, Amanda Pires; Brandão de Mattos, Cinara de Cássia; de Mattos, Luiz Carlos

    2015-01-01

    This study investigated whether polymorphisms of the MICA (major histocompatibility complex class I chain-related gene A) gene are associated with eye lesions due to Toxoplasma gondii infection in a group of immunocompetent patients from southeastern Brazil. The study enrolled 297 patients with serological diagnosis of toxoplasmosis. Participants were classified into two distinct groups after conducting fundoscopic exams according to the presence (n = 148) or absence (n = 149) of ocular scars/lesions due to toxoplasmosis. The group of patients with scars/lesions was further subdivided into two groups according to the type of the ocular manifestation observed: primary (n = 120) or recurrent (n = 28). Genotyping of the MICA and HLA alleles was performed by the polymerase chain reaction-sequence specific oligonucleotide technique (PCR-SSO; One Lambda®) and the MICA-129 polymorphism (rs1051792) was identified by nested polymerase chain reaction (PCR-RFLP). Significant associations involving MICA polymorphisms were not found. Although the MICA*002~HLA-B*35 haplotype was associated with increased risk of developing ocular toxoplasmosis (P-value = 0.04; OR = 2.20; 95% CI = 1.05–4.60), and the MICA*008~HLA-C*07 haplotype was associated with protection against the development of manifestations of ocular toxoplasmosis (P-value = 0.009; OR: 0.44; 95% CI: 0.22–0.76), these associations were not statistically significant after adjusting for multiple comparisons. MICA polymorphisms do not appear to influence the development of ocular lesions in patients diagnosed with toxoplasmosis in this study population. PMID:26672749

  3. Enhanced vaccine-induced CD8+ T cell responses to malaria antigen ME-TRAP by fusion to MHC class ii invariant chain.

    Directory of Open Access Journals (Sweden)

    Alexandra J Spencer

    Full Text Available The orthodox role of the invariant chain (CD74; Ii is in antigen presentation to CD4+ T cells, but enhanced CD8+ T cells responses have been reported after vaccination with vectored viral vaccines encoding a fusion of Ii to the antigen of interest. In this study we assessed whether fusion of the malarial antigen, ME-TRAP, to Ii could increase the vaccine-induced CD8+ T cell response. Following single or heterologous prime-boost vaccination of mice with a recombinant chimpanzee adenovirus vector, ChAd63, or recombinant modified vaccinia virus Ankara (MVA, higher frequencies of antigen-specific CD4+ and CD8+ T cells were observed, with the largest increases observed following a ChAd63-MVA heterologous prime-boost regimen. Studies in non-human primates confirmed the ability of Ii-fusion to augment the T cell response, where a 4-fold increase was maintained up to 11 weeks after the MVA boost. Of the numerous different approaches explored to increase vectored vaccine induced immunogenicity over the years, fusion to the invariant chain showed a consistent enhancement in CD8+ T cell responses across different animal species and may therefore find application in the development of vaccines against human malaria and other diseases where high levels of cell-mediated immunity are required.

  4. Bioaccumulative and conchological assessment of heavy metal transfer in a soil-plant-snail food chain

    Directory of Open Access Journals (Sweden)

    Nica Dragos V

    2012-06-01

    Full Text Available Abstract Background Copper (Cu, zinc (Zn, cadmium (Cd, and lead (Pb can pose serious threats to environmental health because they tend to bioaccumulate in terrestrial ecosystems. We investigated under field conditions the transfer of these heavy metals in a soil-plant-snail food chain in Banat area, Romania. The main goal of this paper was to assess the Roman snail (Helix pomatia usefulness in environmental monitoring as bioindicator of heavy metal accumulation. Eight sampling sites, selected by different history of heavy metal (HM exposure, were chosen to be sampled for soil, nettle leaves, and newly matured snails. This study also aimed to identify the putative effects of HM accumulation in the environment on phenotypic variability in selected shell features, which included shell height (SH, relative shell height (RSH, and whorl number (WN. Results Significantly higher amounts of HMs were accumulated in snail hepatopancreas and not in foot. Cu, Zn, and Cd have biomagnified in the snail body, particularly in the hepatopancreas. In contrast, Pb decreased when going up into the food chain. Zn, Cd, and Pb correlated highly with each other at all levels of the investigated food chain. Zn and Pb exhibited an effective soil–plant transfer, whereas in the snail body only foot Cu concentration was correlated with that in soil. There were significant differences among sampling sites for WN, SH, and RSH when compared with reference snails. WN was strongly correlated with Cd and Pb concentrations in nettle leaves but not with Cu and Zn. SH was independent of HM concentrations in soil, snail hepatopancreas, and foot. However, SH correlated negatively with nettle leaves concentrations for each HM except Cu. In contrast, RSH correlated significantly only with Pb concentration in hepatopancreas. Conclusions The snail hepatopancreas accumulates high amounts of HMs, and therefore, this organ can function as a reliable biomarker for tracking HM bioavailability

  5. CD98 Heavy Chain Is a Potent Positive Regulator of CD4+ T Cell Proliferation and Interferon-γ Production In Vivo.

    Directory of Open Access Journals (Sweden)

    Takeshi Kurihara

    Full Text Available Upon their recognition of antigens presented by the MHC, T cell proliferation is vital for clonal expansion and the acquisition of effector functions, which are essential for mounting adaptive immune responses. The CD98 heavy chain (CD98hc, Slc3a2 plays a crucial role in the proliferation of both CD4+ and CD8+ T cells, although it is unclear if CD98hc directly regulates the T cell effector functions that are not linked with T cell proliferation in vivo. Here, we demonstrate that CD98hc is required for both CD4+ T cell proliferation and Th1 functional differentiation. T cell-specific deletion of CD98hc did not affect T cell development in the thymus. CD98hc-deficient CD4+ T cells proliferated in vivo more slowly as compared with control T cells. C57BL/6 mice lacking CD98hc in their CD4+ T cells could not control Leishmania major infections due to lowered IFN-γ production, even with massive CD4+ T cell proliferation. CD98hc-deficient CD4+ T cells exhibited lower IFN-γ production compared with wild-type T cells, even when comparing IFN-γ expression in cells that underwent the same number of cell divisions. Therefore, these data indicate that CD98hc is required for CD4+ T cell expansion and functional Th1 differentiation in vivo, and suggest that CD98hc might be a good target for treating Th1-mediated immune disorders.

  6. Loss of smooth muscle myosin heavy chain results in the bladder ...

    Indian Academy of Sciences (India)

    MEIJUAN LI

    2018-05-25

    May 25, 2018 ... and no SM-MHC protein has been detected. Compared to the wild-type ..... was blocked with 5% skimmed milk and incubated with the rabbit ..... mice are influenced by the dietary fat content and the degree of murine obesity.

  7. Myosin heavy chain proteins are responsible for the development of obstructive sleep apnea syndrome

    Czech Academy of Sciences Publication Activity Database

    Šedý, Jiří; Horká, E.; Pavlíková, G.; Bulík, O.; Foltán, R.

    2009-01-01

    Roč. 73, č. 6 (2009), s. 1014-1016 ISSN 0306-9877 Institutional research plan: CEZ:AV0Z50390512 Keywords : obstructive sleep apnea syndrome * MHC Subject RIV: FH - Neurology Impact factor: 1.393, year: 2009

  8. A Trypanosoma brucei kinesin heavy chain promotes parasite growth by triggering host arginase activity.

    Directory of Open Access Journals (Sweden)

    Géraldine De Muylder

    2013-10-01

    Full Text Available In order to promote infection, the blood-borne parasite Trypanosoma brucei releases factors that upregulate arginase expression and activity in myeloid cells.By screening a cDNA library of T. brucei with an antibody neutralizing the arginase-inducing activity of parasite released factors, we identified a Kinesin Heavy Chain isoform, termed TbKHC1, as responsible for this effect. Following interaction with mouse myeloid cells, natural or recombinant TbKHC1 triggered SIGN-R1 receptor-dependent induction of IL-10 production, resulting in arginase-1 activation concomitant with reduction of nitric oxide (NO synthase activity. This TbKHC1 activity was IL-4Rα-independent and did not mirror M2 activation of myeloid cells. As compared to wild-type T. brucei, infection by TbKHC1 KO parasites was characterized by strongly reduced parasitaemia and prolonged host survival time. By treating infected mice with ornithine or with NO synthase inhibitor, we observed that during the first wave of parasitaemia the parasite growth-promoting effect of TbKHC1-mediated arginase activation resulted more from increased polyamine production than from reduction of NO synthesis. In late stage infection, TbKHC1-mediated reduction of NO synthesis appeared to contribute to liver damage linked to shortening of host survival time.A kinesin heavy chain released by T. brucei induces IL-10 and arginase-1 through SIGN-R1 signaling in myeloid cells, which promotes early trypanosome growth and favors parasite settlement in the host. Moreover, in the late stage of infection, the inhibition of NO synthesis by TbKHC1 contributes to liver pathogenicity.

  9. MHC and Evolution in Teleosts

    OpenAIRE

    Grimholt, Unni

    2016-01-01

    Major histocompatibility complex (MHC) molecules are key players in initiating immune responses towards invading pathogens. Both MHC class I and class II genes are present in teleosts, and, using phylogenetic clustering, sequences from both classes have been classified into various lineages. The polymorphic and classical MHC class I and class II gene sequences belong to the U and A lineages, respectively. The remaining class I and class II lineages contain nonclassical gene sequences that, de...

  10. Biosynthesis and characterization of a non-repetitive polypeptide derived from silk fibroin heavy chain

    Energy Technology Data Exchange (ETDEWEB)

    Yang, Gaoqiang; Wu, Mingyang; Yi, Honggen; Wang, Jiannan, E-mail: wangjn@suda.edu.cn

    2016-02-01

    Silk fibroin heavy chain is the major protein component of Bombyx mori silk fibroin and is composed of 12 repetitive and 11 non-repetitive regions, with the non-repetitive domain consisting of a hydrophilic polypeptide chain. In order to determine the biomedical function of the non-repetitive domain or potentially use it to modify hydrophobic biomaterials, high-purity isolation is necessary. Previously, we cloned and extended a gene motif (f(1)) encoding the non-repetitive domain. Here, this motif and its multimers are inserted into a glutathione S-transferase (GST)-tagged fusion-protein expression vector. Motif f(1) and multimers f(4) and f(8) were expressed in Escherichia coli BL21 cells following isopropyl β-D-1-thiogalactopyranoside induction, purified by GST-affinity chromatography, and single bands of purified fusion proteins GST-F(1), GST-F(4), and GST-F(8), were visualized by sodium dodecyl sulfate-polyacrylamide gel electrophoresis. Target polypeptides F(1), F(4), and F(8), were cleaved clearly from the GST-fusion tag following thrombin digestion. Mass spectrometry results indicate that the molecular weights associated with fusion proteins GST-F(1), GST-F(4), and GST-F(8) are 31.5, 43.8, and 59.0 kDa, respectively, and with the cleaved polypeptides F(1), F(4), and F(8) are 4.8, 16.8, and 32.8 kDa, respectively. The F(1), F(4), and F(8) polypeptide chains are negatively charged with isoelectric points (pI) of 3.3, 3.2, and 3.0, respectively. The molecular weight and pI values of the polypeptide chains are consistent with the predicted values and the amino acid compositions similar to predicted sequences. FTIR and CD results show the molecular conformation of F(1) was mainly random coil, and more stable α-helix structure formed in longer molecular chain. - Highlights: • A non-repetitive domain and its multimers of silk fibroin were expressed by E. coli. • The corresponding target polypeptides F(1), F(4) and F(8) were cleaved clearly. • Their

  11. Generation of human scFv antibody libraries: PCR amplification and assembly of light- and heavy-chain coding sequences.

    Science.gov (United States)

    Andris-Widhopf, Jennifer; Steinberger, Peter; Fuller, Roberta; Rader, Christoph; Barbas, Carlos F

    2011-09-01

    The development of therapeutic antibodies for use in the treatment of human diseases has long been a goal for many researchers in the antibody field. One way to obtain these antibodies is through phage-display libraries constructed from human lymphocytes. This protocol describes the construction of human scFv (single chain antibody fragment) libraries using a short linker (GGSSRSS) or a long linker (GGSSRSSSSGGGGSGGGG). In this method, the individual rearranged heavy- and light-chain variable regions are amplified separately and are linked through a series of overlap polymerase chain reaction (PCR) steps to give the final scFv products that are used for cloning.

  12. Camelid-derived heavy-chain nanobody against Clostridium botulinum neurotoxin E in Pichia pastoris.

    Science.gov (United States)

    Baghban, Roghayyeh; Gargari, Seyed Latif Mousavi; Rajabibazl, Masoumeh; Nazarian, Shahram; Bakherad, Hamid

    2016-01-01

    Botulinum neurotoxins (BoNTs) result in severe and often fatal disease, botulism. Common remedial measures such as equine antitoxin and human botulism immunoglobulin in turn are problematic and time-consuming. Therefore, diagnosis and therapy of BoNTs are vital. The variable domain of heavy-chain antibodies (VHH) has unique features, such as the ability to identify and bind specifically to target epitopes and ease of production in bacteria and yeast. The Pichia pastoris is suitable for expression of recombinant antibody fragments. Disulfide bond formation and correct folds of protein with a high yield are some of the advantages of this eukaryotic host. In this study, we have expressed and purified the camelid VHH against BoNT/E in P. pastoris. The final yield of P. pastoris-expressed antibody was estimated to be 16 mg/l, which is higher than that expressed by Escherichia coli. The nanobody expressed in P. pastoris neutralized 4LD50 of the BoNT/E upon i.p. injection in 25% of mice. The nanobody expressed in E. coli extended the mice's survival to 1.5-fold compared to the control. This experiment indicated that the quality of expressed protein in the yeast is superior to that of the bacterial expression. Favorable protein folding by P. pastoris seems to play a role in its better toxin-binding property. © 2014 International Union of Biochemistry and Molecular Biology, Inc.

  13. Generation and Characterization of Polyclonal Antibody Against Part of Immunoglobulin Constant Heavy υ Chain of Goose

    Science.gov (United States)

    Zhao, Panpan; Guo, Yongli; Ma, Bo; Wang, Junwei

    2014-01-01

    Immunoglobulin Y (abbreviated as IgY) is a type of immunoglobulin that is the major antibody in bird, reptile, and lungfish blood. IgY consists of two light (λ) and two heavy (υ) chains. In the present study, polyclonal antibody against IgYFc was generated and evaluated. rIgYCυ3/Cυ4 was expressed in Escherichia coli, purified and utilized to raise polyclonal antibody in rabbit. High affinity antisera were obtained, which successfully detected the antigen at a dilution of 1:204,800 for ELISA assay. The antibody can specifically recognize both rIgYCυ3/Cυ4 and native IgY by Western bolt analysis. Furthermore, the serum of Grus japonensis or immunoglobulin of chicken, duck, turkey, and silkie samples and dynamic changes of serum GoIgY after immunogenicity with GPV-VP3-virus-like particles (GPV-VP3-VLPs) can be detected with the anti-GoIgYFc polyclonal antibody. These results suggested that the antibody is valuable for the investigation of biochemical properties and biological functions of GoIgY. PMID:25171010

  14. RUNX1-induced silencing of non-muscle myosin heavy chain IIB contributes to megakaryocyte polyploidization.

    Science.gov (United States)

    Lordier, Larissa; Bluteau, Dominique; Jalil, Abdelali; Legrand, Céline; Pan, Jiajia; Rameau, Philippe; Jouni, Dima; Bluteau, Olivier; Mercher, Thomas; Leon, Catherine; Gachet, Christian; Debili, Najet; Vainchenker, William; Raslova, Hana; Chang, Yunhua

    2012-03-06

    Megakaryocytes are unique mammalian cells that undergo polyploidization (endomitosis) during differentiation, leading to an increase in cell size and protein production that precedes platelet production. Recent evidence demonstrates that endomitosis is a consequence of a late failure in cytokinesis associated with a contractile ring defect. Here we show that the non-muscle myosin IIB heavy chain (MYH10) is expressed in immature megakaryocytes and specifically localizes in the contractile ring. MYH10 downmodulation by short hairpin RNA increases polyploidization by inhibiting the return of 4N cells to 2N, but other regulators, such as of the G1/S transition, might regulate further polyploidization of the 4N cells. Conversely, re-expression of MYH10 in the megakaryocytes prevents polyploidization and the transition of 2N to 4N cells. During polyploidization, MYH10 expression is repressed by the major megakaryocyte transcription factor RUNX1. Thus, RUNX1-mediated silencing of MYH10 is required for the switch from mitosis to endomitosis, linking polyploidization with megakaryocyte differentiation.

  15. A Mouse Neurodegenerative Dynein Heavy Chain Mutation Alters Dynein Motility and Localization in Neurospora crassa

    Science.gov (United States)

    Sivagurunathan, Senthilkumar; Schnittker, Robert R.; Nandini, Swaran; Plamann, Michael D.; King, Stephen J.

    2013-01-01

    Cytoplasmic dynein is responsible for the transport and delivery of cargoes in organisms ranging from humans to fungi. Dysfunction of dynein motor machinery due to mutations in dynein or its activating complex dynactin can result in one of several neurological diseases in mammals. The mouse Legs at odd angles (Loa) mutation in the tail domain of the dynein heavy chain has been shown to lead to progressive neurodegeneration in mice. The mechanism by which the Loa mutation affects dynein function is just beginning to be understood. In this work, we generated the dynein tail mutation observed in Loa mice into the Neurospora crassa genome and utilized cell biological and complementing biochemical approaches to characterize how that tail mutation affected dynein function. We determined that the Loa mutation exhibits several subtle defects upon dynein function in N. crassa that were not seen in mice, including alterations in dynein localization, impaired velocity of vesicle transport, and in the biochemical properties of purified motors. Our work provides new information on the role of the tail domain on dynein function and points out areas of future research that will be of interest to pursue in mammalian systems. PMID:22991199

  16. Prognostic value of serum heavy/light chain ratios in patients with POEMS syndrome.

    Science.gov (United States)

    Wang, Chen; Su, Wei; Cai, Qian-Qian; Cai, Hao; Ji, Wei; Di, Qian; Duan, Ming-Hui; Cao, Xin-Xin; Zhou, Dao-Bin; Li, Jian

    2016-07-01

    POEMS syndrome is a rare plasma cell dyscrasia. Serum concentrations of the monoclonal protein in this disorder are typically low, and inapplicable to monitor disease activity in most cases, resulting in limited practical and prognostic values. Novel immunoassays measuring isotype-specific heavy/light chain (HLC) pairs showed its utility in disease monitoring and outcome prediction in several plasma cell dyscrasias. We report results of HLC measurements in 90 patients with POEMS syndrome. Sixty-six patients (73%; 95% confidence interval, 63-82%) had an abnormal HLC ratio at baseline. It could stratify the risk of disease relapse and was strongly associated with worse progression-free survival in a multivariate analysis (P = 0.021; hazard ratio [HR] 6.89, 95% CI 1.34-35.43). After therapy, HLC ratios improved, with 43 patients (48%) remaining abnormal. The post-therapeutic HLC ratio, if abnormal, also remained as an independent prognostic factor associated with worse progression-free survival (P = 0.019; HR 4.30, 95% CI 1.27-14.56). These results suggest the prognostic utility of HLC ratios in clinical management of POEMS patients. © 2015 John Wiley & Sons A/S. Published by John Wiley & Sons Ltd.

  17. Clathrin heavy chain 1 is required for spindle assembly and chromosome congression in mouse oocytes.

    Science.gov (United States)

    Zhao, Jie; Wang, Lu; Zhou, Hong-Xia; Liu, Li; Lu, Angeleem; Li, Guang-Peng; Schatten, Heide; Liang, Cheng-Guang

    2013-10-01

    Clathrin heavy chain 1 (CLTC) has been considered a “moonlighting protein” which acts in membrane trafficking during interphase and in stabilizing spindle fibers during mitosis. However, its roles in meiosis, especially in mammalian oocyte maturation, remain unclear. This study investigated CLTC expression and function in spindle formation and chromosome congression during mouse oocyte meiotic maturation. Our results showed that the expression level of CLTC increased after germinal vesicle breakdown (GVBD) and peaked in the M phase. Immunostaining results showed CLTC distribution throughout the cytoplasm in a cell cycle-dependent manner. Appearance and disappearance of CLTC along with β-tubulin (TUBB) could be observed during spindle dynamic changes. To explore the relationship between CLTC and microtubule dynamics, oocytes at metaphase were treated with taxol or nocodazole. CLTC colocalized with TUBB at the enlarged spindle and with cytoplasmic asters after taxol treatment; it disassembled and distributed into the cytoplasm along with TUBB after nocodazole treatment. Disruption of CLTC function using stealth siRNA caused a decreased first polar body extrusion rate and extensive spindle formation and chromosome congression defects. Taken together, these results show that CLTC plays an important role in spindle assembly and chromosome congression through a microtubule correlation mechanism during mouse oocyte maturation.

  18. Phosphoneurofilament heavy chain and N-glycomics from the cerebrospinal fluid in amyotrophic lateral sclerosis.

    Science.gov (United States)

    Gonçalves, Margarida; Tillack, Linda; de Carvalho, Mamede; Pinto, Susana; Conradt, Harald S; Costa, Júlia

    2015-01-01

    Amyotrophic Lateral Sclerosis (ALS) is a fatal neurodegenerative disease of the motor neuron for which no clinically validated biomarkers have been identified. We have quantified by ELISA the biomarker phosphoneurofilament heavy chain (pNFH) in the cerebrospinal fluid (CSF) of ALS patients (n=29) and age-matched control patients with other diseases (n=19) by ELISA. Furthermore, we compared protein N-glycosylation of the CSF in ALS patients and controls, by applying a glycomics approach based on liquid chromatography and mass spectrometry. pNFH levels were significantly higher in ALS patients in comparison with controls (P<0.0001) in particular in fast progressors. The N-glycans found in the CSF were predominantly complex diantennary with sialic acid in α2,3- and α2,6-linkage, and bisecting N-acetylglucosamine-containing structures as well as peripherally fucosylated structures were found. As compared with controls the ALS group had a significant increase of a peak composed of the monosialylated diantennary glycans A2G2S(6)1 and FA2G2S(3)1 (P=0.0348). Our results underscore the value of pNFH as a biomarker in ALS. In addition, we identified a variation of the N-glycosylation pattern in ALS, suggesting that this change should be explored in future studies as potential biomarker. Copyright © 2014 Elsevier B.V. All rights reserved.

  19. Iron Deposition and Ferritin Heavy Chain (Fth Localization in Rodent Teeth

    Directory of Open Access Journals (Sweden)

    Wen Xin

    2013-01-01

    Full Text Available Abstract Background An iron rich layer on the labial surface is characteristic of the enamel of rodent incisors. In order to address a role for iron content in continuously growing incisors during odontogenesis, we studied iron deposition patterns in enamel and dentine using Perls’ blue staining and ferritin heavy chain (Fth immunolocalization. Fth expression is regulated by iron level; therefore its localization can be used as a sensitive indicator for iron deposition. Results Sagittal sections of 4-week old rat incisors showed a gradual increase in iron level in the enamel organ from secretory to maturation stages. In addition, iron was detected in ameloblasts of erupting third molars of 4-week old rats, suggesting iron plays a role in both incisor and molar development. In odontoblasts, the presence of iron was demonstrated, and this is consistent with iron’s role in collagen synthesis. Using postnatal 3-, 6-, 9-day old mice, the spatial and temporal expression of Fth in tooth development again indicated the presence of iron in mature ameloblasts and odontoblasts. Conclusions While these data do not explain what functional role iron has in tooth formation, it does highlight a significant molecular activity associated with the formation of the rodent dentition.

  20. Combination of neurofilament heavy chain and complement c3 as CSF biomarkers for ALS

    Science.gov (United States)

    Ganesalingam, Jeban; An, Jiyan; Shaw, Christopher E; Shaw, Gerry; Lacomis, David; Bowser, Robert

    2011-01-01

    Amyotrophic lateral sclerosis (ALS) is a rapidly progressive and ultimately fatal neurodegenerative disease with an average survival of 3 years from symptom onset. Rapid and conclusive early diagnosis is essential if interventions with disease-modifying therapies are to be successful. Cytoskeletal modification and inflammation are known to occur during the pathogenesis of ALS. We measured levels of cytoskeletal proteins and inflammatory markers in the cerebrospinal fluid (CSF) of ALS, disease controls and healthy subjects. We determined threshold values for each protein that provided the optimal sensitivity and specificity for ALS within a training set, as determined by receiver operating characteristic (ROC) analysis. Interestingly, the optimal assay was a ratio of the levels for phosphorylated neurofilament heavy chain and complement C3 (pNFH/C3). We next applied this assay to a separate test set of CSF samples to verify our results. Overall, the predictive pNFH/C3 ratio identified ALS with 87.3% sensitivity and 94.6% specificity in a total of 71 ALS subjects, 52 disease control subjects and 40 healthy subjects. In addition, the level of CSF pNFH correlated with survival of ALS patients. We also detected increased pNFH in the plasma of ALS patients and observed a correlation between CSF and plasma pNFH levels within the same subjects. These findings support large-scale prospective biomarker studies to determine the clinical utility of diagnostic and prognostic signatures in ALS. PMID:21418221

  1. Expression, purification and preliminary X-ray crystallographic analysis of the chicken MHC class I molecule YF1*7.1

    International Nuclear Information System (INIS)

    Hee, Chee Seng; Gao, Song; Miller, Marcia M.; Goto, Ronald M.; Ziegler, Andreas; Daumke, Oliver; Uchanska-Ziegler, Barbara

    2009-01-01

    The chicken classical MHC class I antigen YF1*7.1 was crystallized together with β 2 -microglobulin but without a peptide ligand. Crystals diffracted synchrotron radiation to 1.32 Å and belonged to the monoclinic space group P2 1 . YF1*7.1 is an allele of a polymorphic major histocompatibility complex (MHC) class I-like locus within the chicken Y gene complex. With the aim of understanding the possible role of the YF1*7.1 molecule in antigen presentation, the complex of YF1*7.1 heavy chain and β 2 -microglobulin was reconstituted and purified without a peptide. Crystals diffracted synchrotron radiation to 1.32 Å resolution and belonged to the monoclinic space group P2 1 . The phase problem was solved by molecular replacement. A detailed examination of the structure may provide insight into the type of ligand that could be bound by the YF1*7.1 molecule

  2. Functional recombinant MHC class II molecules and high-throughput peptide-binding assays

    DEFF Research Database (Denmark)

    Justesen, Sune; Harndahl, Mikkel; Lamberth, Kasper

    2009-01-01

    BACKGROUND: Molecules of the class II major histocompability complex (MHC-II) specifically bind and present exogenously derived peptide epitopes to CD4+ T helper cells. The extreme polymorphism of the MHC-II hampers the complete analysis of peptide binding. It is also a significant hurdle......-II molecules and accompanying HTS peptide-binding assay were successfully developed for nine different MHC-II molecules including the DPA1*0103/DPB1*0401 (DP401) and DQA1*0501/DQB1*0201, where both alpha and beta chains are polymorphic, illustrating the advantages of producing the two chains separately....... CONCLUSION: We have successfully developed versatile MHC-II resources, which may assist in the generation of MHC class II -wide reagents, data, and tools....

  3. Generation of human Fab antibody libraries: PCR amplification and assembly of light- and heavy-chain coding sequences.

    Science.gov (United States)

    Andris-Widhopf, Jennifer; Steinberger, Peter; Fuller, Roberta; Rader, Christoph; Barbas, Carlos F

    2011-09-01

    The development of therapeutic antibodies for use in the treatment of human diseases has long been a goal for many researchers in the antibody field. One way to obtain these antibodies is through phage-display libraries constructed from human lymphocytes. This protocol describes the construction of human Fab (fragment antigen binding) antibody libraries. In this method, the individual rearranged heavy- and light-chain variable regions are amplified separately and are linked through a series of overlap polymerase chain reaction (PCR) steps to give the final Fab products that are used for cloning.

  4. Comparison of new ELISA method with established SDS-PAGE method for determination of muscle myosin heavy chain isoforms

    Czech Academy of Sciences Publication Activity Database

    Říčný, Jan; Soukup, Tomáš

    2011-01-01

    Roč. 60, č. 6 (2011), s. 899-904 ISSN 0862-8408 R&D Projects: GA ČR(CZ) GA304/08/0256 Grant - others:EC(XE) LSH-CT-2004-511978 Institutional research plan: CEZ:AV0Z50110509 Keywords : muscle fiber types * myosin heavy chains * SDS - PAGE * immunoreactions * thyroid hormones * ELISA Subject RIV: EA - Cell Biology Impact factor: 1.555, year: 2011

  5. Construction and characterization of the alpha form of a cardiac myosin heavy chain cDNA clone and its developmental expression in the Syrian hamster.

    OpenAIRE

    Liew, C C; Jandreski, M A

    1986-01-01

    A cDNA clone, pVHC1, was isolated from a Syrian hamster heart cDNA library and was compared to the rat alpha (pCMHC21) and beta (pCMHC5) ventricular myosin heavy chain cDNA clones. The DNA sequence and amino acid sequence deducted from the DNA show more homology with pCMHC21 than pCMHC5. This indicates that pVHC1 is an alpha ventricular myosin heavy chain cDNA clone. However, even though pVHC1 shows a high degree of nucleotide and amino acid conservation with the rat myosin heavy chain sequen...

  6. Ku70 is required for late B cell development and immunoglobulin heavy chain class switching.

    Science.gov (United States)

    Manis, J P; Gu, Y; Lansford, R; Sonoda, E; Ferrini, R; Davidson, L; Rajewsky, K; Alt, F W

    1998-06-15

    Immunoglobulin (Ig) heavy chain (HC) class switch recombination (CSR) is a late B cell process that involves intrachromosomal DNA rearrangement. Ku70 and Ku80 form a DNA end-binding complex required for DNA double strand break repair and V(D)J recombination. Ku70(-/-) (K70T) mice, like recombination activating gene (RAG)-1- or RAG-2-deficient (R1T or R2T) mice, have impaired B and T cell development at an early progenitor stage, which is thought to result at least in part from defective V(D)J recombination (Gu, Y., K.J. Seidl, G.A. Rathbun, C. Zhu, J.P. Manis, N. van der Stoep, L. Davidson, H.L. Cheng, J.M. Sekiguchi, K. Frank, et al. 1997. Immunity. 7:653-665; Ouyang, H., A. Nussenzweig, A. Kurimasa, V.C. Soares, X. Li, C. Cordon-Cardo, W. Li, N. Cheong, M. Nussenzweig, G. Iliakis, et al. 1997. J. Exp. Med. 186:921-929). Therefore, to examine the potential role of Ku70 in CSR, we generated K70T mice that carry a germline Ig HC locus in which the JH region was replaced with a functionally rearranged VH(D)JH and Ig lambda light chain transgene (referred to as K70T/HL mice). Previously, we have shown that B cells from R1T or R2T mice carrying these rearranged Ig genes (R1T/HL or R2T/HL mice) can undergo CSR to IgG isotypes (Lansford, R., J. Manis, E. Sonoda, K. Rajewsky, and F. Alt. 1998. Int. Immunol. 10:325-332). K70T/HL mice had significant numbers of peripheral surface IgM+ B cells, which generated serum IgM levels similar to those of R2T/HL mice. However, in contrast to R2T/HL mice, K70T/HL mice had no detectable serum IgG isotypes. In vitro culture of K70T/HL B cells with agents that induce CSR in normal or R2T/HL B cells did lead to the induction of germline CH transcripts, indicating that initial signaling pathways for CSR were intact in K70T/HL cells. However, treatment with such agents did not lead to detectable CSR by K70T/HL B cells, and instead, led to cell death within 72 h. We conclude that Ku70 is required for the generation of B cells that have

  7. Large-scale chromatin remodeling at the immunoglobulin heavy chain locus: a paradigm for multigene regulation.

    Science.gov (United States)

    Bolland, Daniel J; Wood, Andrew L; Corcoran, Anne E

    2009-01-01

    V(D)J recombination in lymphocytes is the cutting and pasting together of antigen receptor genes in cis to generate the enormous variety of coding sequences required to produce diverse antigen receptor proteins. It is the key role of the adaptive immune response, which must potentially combat millions of different foreign antigens. Most antigen receptor loci have evolved to be extremely large and contain multiple individual V, D and J genes. The immunoglobulin heavy chain (Igh) and immunoglobulin kappa light chain (Igk) loci are the largest multigene loci in the mammalian genome and V(D)J recombination is one of the most complicated genetic processes in the nucleus. The challenge for the appropriate lymphocyte is one of macro-management-to make all of the antigen receptor genes in a particular locus available for recombination at the appropriate developmental time-point. Conversely, these large loci must be kept closed in lymphocytes in which they do not normally recombine, to guard against genomic instability generated by the DNA double strand breaks inherent to the V(D)J recombination process. To manage all of these demanding criteria, V(D)J recombination is regulated at numerous levels. It is restricted to lymphocytes since the Rag genes which control the DNA double-strand break step of recombination are only expressed in these cells. Within the lymphocyte lineage, immunoglobulin recombination is restricted to B-lymphocytes and TCR recombination to T-lymphocytes by regulation of locus accessibility, which occurs at multiple levels. Accessibility of recombination signal sequences (RSSs) flanking individual V, D and J genes at the nucleosomal level is the key micro-management mechanism, which is discussed in greater detail in other chapters. This chapter will explore how the antigen receptor loci are regulated as a whole, focussing on the Igh locus as a paradigm for the mechanisms involved. Numerous recent studies have begun to unravel the complex and

  8. Role of kinesin heavy chain in Crumbs localization along the rhabdomere elongation in Drosophila photoreceptor.

    Directory of Open Access Journals (Sweden)

    Garrett P League

    Full Text Available BACKGROUND: Crumbs (Crb, a cell polarity gene, has been shown to provide a positional cue for the extension of the apical membrane domain, adherens junction (AJ, and rhabdomere along the growing proximal-distal axis during Drosophila photoreceptor morphogenesis. In developing Drosophila photoreceptors, a stabilized microtubule structure was discovered and its presence was linked to polarity protein localization. It was therefore hypothesized that the microtubules may provide trafficking routes for the polarity proteins during photoreceptor morphogenesis. This study has examined whether Kinesin heavy chain (Khc, a subunit of the microtubule-based motor Kinesin-1, is essential in polarity protein localization in developing photoreceptors. METHODOLOGY/PRINCIPAL FINDINGS: Because a genetic interaction was found between crb and khc, Crb localization was examined in the developing photoreceptors of khc mutants. khc was dispensable during early eye differentiation and development. However, khc mutant photoreceptors showed a range of abnormalities in the apical membrane domain depending on the position along the proximal-distal axis in pupal photoreceptors. The khc mutant showed a progressive mislocalization in the apical domain along the distal-proximal axis during rhabdomere elongation. The khc mutation also led to a similar progressive defect in the stabilized microtubule structures, strongly suggesting that Khc is essential for microtubule structure and Crb localization during distal to proximal rhabdomere elongation in pupal morphogenesis. This role of Khc in apical domain control was further supported by khc's gain-of-function phenotype. Khc overexpression in photoreceptors caused disruption of the apical membrane domain and the stabilized microtubules in the developing photoreceptors. CONCLUSIONS/SIGNIFICANCE: In summary, we examined the role of khc in the regulation of the apical Crb domain in developing photoreceptors. Since the rhabdomeres in

  9. Postnatal development of cerebellar zones revealed by neurofilament heavy chain protein expression

    Directory of Open Access Journals (Sweden)

    Joshua J White

    2013-05-01

    Full Text Available The cerebellum is organized into parasagittal zones that control sensory-motor behavior. Although the architecture of adult zones is well understood, very little is known about how zones emerge during development. Understanding the process of zone formation is an essential step towards unraveling how circuits are constructed to support specific behaviors. Therefore, we focused this study on postnatal development to determine the spatial and temporal changes that establish zonal patterns during circuit formation. We used a combination of wholemount and tissue section immunohistochemistry in mice to show that the cytoskeletal protein neurofilament heavy chain (NFH is a robust marker for postnatal cerebellar zonal patterning. The patterned expression of NFH is initiated shortly after birth, and compared to the domains of several known zonal markers such as zebrin II, HSP25, neurogranin, and phospholipase Cβ4 (PLCβ4, NFH does not exhibit transient expression patterns that are typically remodeled between stages, and the adult zones do not emerge after a period of uniform expression in all lobules. Instead, we found that throughout postnatal development NFH gradually reveals distinct zones in each cerebellar lobule. The boundaries of individual NFH zones sharpen over time, as zones are refined during the second and third weeks after birth. Double labeling with neurogranin and PLCβ4 further revealed that although the postnatal expression of NFH is spatially and temporally unique, its pattern of zones respects a fundamental and well-known molecular topography in the cerebellum. The dynamics of NFH expression support the hypothesis that adult circuits are derived from an embryonic map that is refined into zones during the first three-weeks of life.

  10. Human heavy-chain variable region gene family nonrandomly rearranged in familial chronic lymphocytic leukemia

    International Nuclear Information System (INIS)

    Shen, A.; Humphries, C.; Tucker, P.; Blattner, F.

    1987-01-01

    The authors have identified a family of human immunoglobulin heavy-chain variable-region (V/sub H/) genes, one member of which is rearranged in two affected members of a family in which the father and four of five siblings developed chronic lymphocytic leukemia. Cloning and sequencing of the rearranged V/sub H/ genes from leukemic lymphocytes of three affected siblings showed that two siblings had rearranged V/sub H/ genes (V/sub H/TS1 and V/sub H/WS1) that were 90% homologous. The corresponding germ-line gene, V/sub H/251, was found to part of a small (four gene) V/sub H/ gene family, which they term V/sub H/V. The DNA sequence homology to V/sub H/WS1 (95%) and V/sub H/TS1 (88%) and identical restriction sites on the 5' side of V/sub H/ confirm that rearrangement of V/sub H/251 followed by somatic mutation produced the identical V/sub H/ gene rearrangements in the two siblings. V/sub H/TS1 is not a functional V/sub H/ gene; a functional V/sub H/ rearrangement was found on the other chromosome of this patient. The other two siblings had different V/sub H/ gene rearrangements. All used different diversity genes. Mechanisms proposed for nonrandom selection of a single V/sub H/ gene include developmental regulation of this V/sub H/ gene rearrangement or selection of a subpopulation of B cells in which this V/sub H/ has been rearranged

  11. Muscle fiber type specific induction of slow myosin heavy chain 2 gene expression by electrical stimulation

    International Nuclear Information System (INIS)

    Crew, Jennifer R.; Falzari, Kanakeshwari; DiMario, Joseph X.

    2010-01-01

    Vertebrate skeletal muscle fiber types are defined by a broad array of differentially expressed contractile and metabolic protein genes. The mechanisms that establish and maintain these different fiber types vary throughout development and with changing functional demand. Chicken skeletal muscle fibers can be generally categorized as fast and fast/slow based on expression of the slow myosin heavy chain 2 (MyHC2) gene in fast/slow muscle fibers. To investigate the cellular and molecular mechanisms that control fiber type formation in secondary or fetal muscle fibers, myoblasts from the fast pectoralis major (PM) and fast/slow medial adductor (MA) muscles were isolated, allowed to differentiate in vitro, and electrically stimulated. MA muscle fibers were induced to express the slow MyHC2 gene by electrical stimulation, whereas PM muscle fibers did not express the slow MyHC2 gene under identical stimulation conditions. However, PM muscle fibers did express the slow MyHC2 gene when electrical stimulation was combined with inhibition of inositol triphosphate receptor (IP3R) activity. Electrical stimulation was sufficient to increase nuclear localization of expressed nuclear-factor-of-activated-T-cells (NFAT), NFAT-mediated transcription, and slow MyHC2 promoter activity in MA muscle fibers. In contrast, both electrical stimulation and inhibitors of IP3R activity were required for these effects in PM muscle fibers. Electrical stimulation also increased levels of peroxisome-proliferator-activated receptor-γ co-activator-1 (PGC-1α) protein in PM and MA muscle fibers. These results indicate that MA muscle fibers can be induced by electrical stimulation to express the slow MyHC2 gene and that fast PM muscle fibers are refractory to stimulation-induced slow MyHC2 gene expression due to fast PM muscle fiber specific cellular mechanisms involving IP3R activity.

  12. Effect of ageing on the myosin heavy chain composition of the human sternocleidomastoid muscle.

    Science.gov (United States)

    Meznaric, M; Eržen, I; Karen, P; Cvetko, E

    2018-03-01

    The myosin heavy chain (MyHC) composition of ageing limb muscles is transformed into a slower phenotype and expresses fast-twitch fibre type atrophy, presumably due to age-related motor unit remodelling and a change in the patterns of physical activity. It is not known if ageing affects the sternocleidomastoid muscle (SCM) in a similar way. The goal of the study was to analyze the MyHC composition and the size of muscle fibres in the ageing SCM by immunohistochemical methods and quantitative analysis and stereology using our own software for morphometry. We hypothesize that with ageing the MyHC composition of SCM transforms similarly as in ageing limb muscles, but the size of the muscle fibres is less effected as in limb muscles. The study was performed on the autopsy samples of the SCM in 12 older males. The results were compared with those published in our previous study on 15 young adult males. An ageing SCM transforms into a slower MyHC profile: the percentage of slow-twitch fibres is enhanced (numerical proportion 44.6 vs. 31.5%, Pfibres is diminished (numerical proportion 14.1 vs. 26.8%, Pfast-twitch fibres expressing MyHC-2a and 2x is smaller (50.6 vs. 63.5%, Pfibres expressing the fastest myosin isoform MyHC-2x is smaller too (19.0 vs. 34.5%, Pfibres expressing the fastest MyHC-2x provide circumstantial evidence for: (i) more fast-twitch than slow-twitch motor units being lost; and (ii) reinnervation by the surviving motor units. There appears to be no significant influence on muscle fibre size, which is congruent with relatively unchanged SCM activity during life. Copyright © 2017 Elsevier GmbH. All rights reserved.

  13. Many Routes to an Antibody Heavy-Chain CDR3: Necessary, Yet Insufficient, for Specific Binding

    Science.gov (United States)

    D’Angelo, Sara; Ferrara, Fortunato; Naranjo, Leslie; Erasmus, M. Frank; Hraber, Peter; Bradbury, Andrew R. M.

    2018-01-01

    Because of its great potential for diversity, the immunoglobulin heavy-chain complementarity-determining region 3 (HCDR3) is taken as an antibody molecule’s most important component in conferring binding activity and specificity. For this reason, HCDR3s have been used as unique identifiers to investigate adaptive immune responses in vivo and to characterize in vitro selection outputs where display systems were employed. Here, we show that many different HCDR3s can be identified within a target-specific antibody population after in vitro selection. For each identified HCDR3, a number of different antibodies bearing differences elsewhere can be found. In such selected populations, all antibodies with the same HCDR3 recognize the target, albeit at different affinities. In contrast, within unselected populations, the majority of antibodies with the same HCDR3 sequence do not bind the target. In one HCDR3 examined in depth, all target-specific antibodies were derived from the same VDJ rearrangement, while non-binding antibodies with the same HCDR3 were derived from many different V and D gene rearrangements. Careful examination of previously published in vivo datasets reveals that HCDR3s shared between, and within, different individuals can also originate from rearrangements of different V and D genes, with up to 26 different rearrangements yielding the same identical HCDR3 sequence. On the basis of these observations, we conclude that the same HCDR3 can be generated by many different rearrangements, but that specific target binding is an outcome of unique rearrangements and VL pairing: the HCDR3 is necessary, albeit insufficient, for specific antibody binding. PMID:29568296

  14. Characterization of the Canine MHC Class I DLA-88*50101 Peptide Binding Motif as a Prerequisite for Canine T Cell Immunotherapy.

    Directory of Open Access Journals (Sweden)

    Sharon M Barth

    Full Text Available There are limitations in pre-clinical settings using mice as a basis for clinical development in humans. In cancer, similarities exist between humans and dogs; thus, the dog patient can be a link in the transition from laboratory research on mouse models to clinical trials in humans. Knowledge of the peptides presented on MHC molecules is fundamental for the development of highly specific T cell-based immunotherapies. This information is available for human MHC molecules but is absent for the canine MHC. In the present study, we characterized the binding motif of dog leukocyte antigen (DLA class I allele DLA-88*50101, using human C1R and K562 transfected cells expressing the DLA-88*50101 heavy chain. MHC class I immunoaffinity-purification revealed 3720 DLA-88*50101 derived peptides, which enabled the determination of major anchor positions. The characterized binding motif of DLA-88*50101 was similar to HLA-A*02:01. Peptide binding analyses on HLA-A*02:01 and DLA-88*50101 via flow cytometry showed weak binding of DLA-88*50101 derived peptides to HLA-A*02:01, and vice versa. Our results present for the first time a detailed peptide binding motif of the canine MHC class I allelic product DLA-88*50101. These data support the goal of establishing dogs as a suitable animal model for the evaluation and development of T cell-based cancer immunotherapies, benefiting both dog and human patients.

  15. Removal of round off errors in the matrix exponential method for solving the heavy nuclide chain

    International Nuclear Information System (INIS)

    Lee, Hyun Chul; Noh, Jae Man; Joo, Hyung Kook

    2005-01-01

    Many nodal codes for core simulation adopt the micro-depletion procedure for the depletion analysis. Unlike the macro-depletion procedure, the microdepletion procedure uses micro-cross sections and number densities of important nuclides to generate the macro cross section of a spatial calculational node. Therefore, it needs to solve the chain equations of the nuclides of interest to obtain their number densities. There are several methods such as the matrix exponential method (MEM) and the chain linearization method (CLM) for solving the nuclide chain equations. The former solves chain equations exactly even when the cycles that come from the alpha decay exist in the chain while the latter solves the chain approximately when the cycles exist in the chain. The former has another advantage over the latter. Many nodal codes for depletion analysis, such as MASTER, solve only the hard coded nuclide chains with the CLM. Therefore, if we want to extend the chain by adding some more nuclides to the chain, we have to modify the source code. In contrast, we can extend the chain just by modifying the input in the MEM because it is easy to implement the MEM solver for solving an arbitrary nuclide chain. In spite of these advantages of the MEM, many nodal codes adopt the chain linearization because the former has a large round off error when the flux level is very high or short lived or strong absorber nuclides exist in the chain. In this paper, we propose a new technique to remove the round off errors in the MEM and we compared the performance of the two methods

  16. Prolonged Cre expression driven by the α-myosin heavy chain promoter can be cardiotoxic.

    Science.gov (United States)

    Pugach, Emily K; Richmond, Phillip A; Azofeifa, Joseph G; Dowell, Robin D; Leinwand, Leslie A

    2015-09-01

    Studying the importance of genetic factors in a desired cell type or tissue necessitates the use of precise genetic tools. With the introduction of bacteriophage Cre recombinase/loxP mediated DNA editing and promoter-specific Cre expression, it is feasible to generate conditional knockout mice in which particular genes are disrupted in a cell type-specific manner in vivo. In cardiac myocytes, this is often achieved through α-myosin heavy chain promoter (αMyHC)-driven Cre expression in conjunction with a loxP-site flanked gene of interest. Recent studies in other cell types demonstrate toxicity of Cre expression through induction of DNA damage. However, it is unclear to what extent the traditionally used αMyHC-Cre line [1] may exhibit cardiotoxicity. Further, the genotype of αMyHC-Cre(+/-) is not often included as a control group in cardiac myocyte-specific knockout studies. Here we present evidence that these αMyHC-Cre(+/-) mice show molecular signs of cardiac toxicity by 3months of age and exhibit decreased cardiac function by 6months of age compared to wild-type littermates. Hearts from αMyHC-Cre(+/-) mice also display evidence of fibrosis, inflammation, and DNA damage. Interestingly, some of the early functional changes observed in αMyHC-Cre(+/-) mice are sexually dimorphic. Given the high level of Cre recombinase expression resulting from expression from the αMyHC promoter, we asked if degenerate loxP-like sites naturally exist in the mouse genome and if so, whether they are affected by Cre in the absence of canonical loxP-sites. Using a novel bioinformatics search tool, we identified 619 loxP-like sites with 4 or less mismatches to the canonical loxP-site. 227 sites overlapped with annotated genes and 55 of these genes were expressed in cardiac muscle. Expression of ~26% of the 27 genes tested was disrupted in αMyHC-Cre(+/-) mice indicating potential targeting by Cre. Taken together, these results highlight both the importance of using αMyHC-Cre mice

  17. Botulinum neurotoxin type A radiolabeled at either the light or the heavy chain

    International Nuclear Information System (INIS)

    Dekleva, M.L.; DasGupta, B.R.; Sathyamoorthy, V.

    1989-01-01

    Botulinum neurotoxin (NT) has two distinct structural regions called L and H chains (approximately 50 and approximately 100 kDa, respectively). Although the H chain is responsible for binding of the NT to neuronal cells, it is not known which of the subunits is internalized and therefore responsible for causing the blockage of acetylcholine release in susceptible neuronal cells. In this report we describe for the first time the preparation of type A NT which is selectively radiolabeled at either the L or the H chain subunit. Such NT preparations will be useful as tools for determining the distribution of L and H chains in poisoned neuronal cells and the role that each subunit plays in inducing toxicity. The L and H chains of the NT (approximately 150 kDa) were separated, purified, and then individually radiolabeled by reductive methylation of the lysine residues using [3H]- or [14C]formaldehyde. The labeled L and H chains were reconjugated with the complementary unlabeled L and H chains. Formation of -S-S- and noncovalent bonds between the L and H chains regenerated the approximately 150 kDa NT. Autoradiographs of sodium dodecyl sulfate polyacrylamide gels confirmed that each reconstituted NT preparation was labeled at only one subunit chain. NT selectively labeled at either the L or the H chain had specific radioactivities of ca. 25-30 and 45-55 microCi/mumol, respectively, and toxicity (mouse LD50/mg protein) values of 2.2 +/- 1.1 X 10(7) and 3.0 +/- 1.0 X 10(7), respectively. A linear increase in the specific radioactivity of L and H chain subunits was observed with increasing concentrations of 3H- or 14C-labeled formaldehyde in the reaction mixture and with increasing concentrations of L or H chain in the reaction mixture

  18. Myosin heavy-chain isoform distribution, fibre-type composition and fibre size in skeletal muscle of patients on haemodialysis

    DEFF Research Database (Denmark)

    Molsted, Stig; Eidemak, Inge; Sorensen, Helle Tauby

    2007-01-01

    of age-, gender- and BMI-matched untrained control subjects. The aerobic work capacity of the patients was also determined. Results. The MHC composition for I, IIA and IIX isoforms was found to be 35.3%±18.2%, 35.9%±7.1% and 28.9%±15.6%, respectively, findings supported by the ATPase histochemically...... determined fibre-type composition of the vastus lateralis muscle. The mean fibre area of type 1 and 2 fibres was 3283±873 and 3594±1483 µm2, respectively. The MHC composition and the size of the type 1 fibres of the patients on HD were significantly different from those of the control subjects. Conclusions....... The data demonstrate relatively fewer type 1 and consequently more type 2x fibres, with a corresponding change in MHC isoforms (MHC I and MHC IIX) in the skeletal muscle of patiens on HD. Several patients on HD were found to have type 1 (or relative percentage of MHC I) fibres. Such a low percentage...

  19. Schwann cells promote post-traumatic nerve inflammation and neuropathic pain through MHC class II.

    Science.gov (United States)

    Hartlehnert, Maike; Derksen, Angelika; Hagenacker, Tim; Kindermann, David; Schäfers, Maria; Pawlak, Mathias; Kieseier, Bernd C; Meyer Zu Horste, Gerd

    2017-10-02

    The activation of T helper cells requires antigens to be exposed on the surface of antigen presenting cells (APCs) via MHC class II (MHC-II) molecules. Expression of MHC-II is generally limited to professional APCs, but other cell types can express MHC-II under inflammatory conditions. However, the importance of these conditional APCs is unknown. We and others have previously shown that Schwann cells are potentially conditional APCs, but the functional relevance of MHC-II expression by Schwann cells has not been studied in vivo. Here, we conditionally deleted the MHC-II β-chain from myelinating Schwann cells in mice and investigated how this influenced post-traumatic intraneural inflammation and neuropathic pain using the chronic constriction injury (CCI) model. We demonstrate that deletion of MHC-II in myelinating Schwann cells reduces thermal hyperalgesia and, to a lesser extent, also diminishes mechanical allodynia in CCI in female mice. This was accompanied by a reduction of intraneural CD4+ T cells and greater preservation of preferentially large-caliber axons. Activation of T helper cells by MHC-II on Schwann cells thus promotes post-traumatic axonal loss and neuropathic pain. Hence, we provide experimental evidence that Schwann cells gain antigen-presenting function in vivo and modulate local immune responses and diseases in the peripheral nerves.

  20. B-Lymphoblastic Lymphomas Evolving from Follicular Lymphomas Co-Express Surrogate Light Chains and Mutated Gamma Heavy Chains.

    Science.gov (United States)

    Slot, Linda M; Hoogeboom, Robbert; Smit, Laura A; Wormhoudt, Thera A M; Biemond, Bart J; Oud, Monique E C M; Schilder-Tol, Esther J M; Mulder, André B; Jongejan, Aldo; van Kampen, Antoine H C; Kluin, Philip M; Guikema, Jeroen E J; Bende, Richard J; van Noesel, Carel J M

    2016-12-01

    Follicular lymphoma (FL) is an indolent B-cell non-Hodgkin lymphoma able to transform into germinal center-type diffuse large B-cell lymphoma. We describe four extraordinary cases of FL, which progressed to TdT + CD20 - precursor B-lymphoblastic lymphoma (B-LBL). Fluorescence in situ hybridization analysis showed that all four B-LBLs had acquired a MYC translocation on transformation. Comparative genomic hybridization analysis of one case demonstrated that in addition to 26 numerical aberrations that were shared between the FL and B-LBL, deletion of CDKN2A/B and 17q11, 14q32 amplification, and copy-neutral loss of heterozygosity of 9p were gained in the B-LBL cells. Whole-exome sequencing revealed mutations in FMN2, NEB, and SYNE1 and a nonsense mutation in KMT2D, all shared by the FL and B-LBL, and TNFRSF14, SMARCA2, CCND3 mutations uniquely present in the B-LBL. Remarkably, all four FL-B-LBL pairs expressed IgG. In two B-LBLs, evidence was obtained for ongoing rearrangement of IG light chain variable genes and expression of the surrogate light chain. IGHV mutation analysis showed that all FL-B-LBL pairs harbored identical or near-identical somatic mutations. From the somatic gene alterations found in the IG and non-IG genes, we conclude that the FLs and B-LBLs did not develop in parallel from early t(14;18)-positive IG-unmutated precursors, but that the B-LBLs developed from preexistent FL subclones that accumulated additional genetic damage. Copyright © 2016 American Society for Investigative Pathology. Published by Elsevier Inc. All rights reserved.

  1. Sequences of the joining region genes for immunoglobulin heavy chains and their role in generation of antibody diversity.

    OpenAIRE

    Gough, N M; Bernard, O

    1981-01-01

    To assess the contribution to immunoglobulin heavy chain diversity made by recombination between variable region (VH) genes and joining region (JH) genes, we have determined the sequence of about 2000 nucleotides spanning the rearranged JH gene cluster associated with the VH gene expressed in plasmacytoma HPC76. The active VH76 gene has recombined with the second germ-line JH gene. The region we have studied contains two other JH genes, designated JH3 and JH4. No other JH gene was found withi...

  2. Dimeric MHC-peptides inserted into an immunoglobulin scaffold as new immunotherapeutic agents

    Science.gov (United States)

    Goldberg, Burt; Bona, Constantin

    2011-01-01

    Abstract The interactions of the T cell receptor (TCR) with cognate MHC-peptide and co-stimulatory molecules expressed at surface of antigen presenting cells (APC) leads to activation or tolerance of T cells. The development of molecular biological tools allowed for the preparation of soluble MHC-peptide molecules as surrogate for the APC. A decade ago a monomeric class II MHC molecule in which the peptide was covalently linked to β-chain of class II molecule was generated. This type of molecule had a low-binding affinity and did not cause the multimerization of TCR. The requirement of multimerization of TCR led to development of a new class of reagents, chimeric peptides covalently linked to MHC that was dimerized via Fc fragment of an immunoglobulin and linked to 3′ end of the β-chain of MHC class II molecule. These soluble dimerized MHC-peptide chimeric molecules display high affinity for the TCR and caused multimerization of TCR without processing by an APC. Because dimeric molecules are devoid of co-stimulatory molecules interacting with CD28, a second signal, they induce anergy rather the activation of T cells. In this review, we compare the human and murine dimerized MHC class II-peptides and their effect on CD4+ T cells, particularly the generation of T regulatory cells, which make these chimeric molecules an appealing approach for the treatment of autoimmune diseases. PMID:21435177

  3. Application of monoclonal antibodies in functional and comparative investigations of heavy-chain immunoglobulins in new world camelids.

    Science.gov (United States)

    Daley, L P; Gagliardo, L F; Duffy, M S; Smith, M C; Appleton, J A

    2005-03-01

    Of the three immunoglobulin G (IgG) isotypes described to occur in camelids, IgG2 and IgG3 are distinct in that they do not incorporate light chains. These heavy-chain antibodies (HCAbs) constitute approximately 50% of the IgG in llama serum and as much as 75% of the IgG in camel serum. We have produced isotype-specific mouse monoclonal antibodies (MAbs) in order to investigate the roles of HCAbs in camelid immunity. Seventeen stable hybridomas were cloned, and three MAbs that were specific for epitopes on the gamma chains of llama IgG1, IgG2, or IgG3 were characterized in detail. Affinity chromatography revealed that each MAb bound its isotype in solution in llama serum. The antibodies bound to the corresponding alpaca IgGs, to guanaco IgG1 and IgG2, and to camel IgG1. Interestingly, anti-IgG2 MAbs bound three heavy-chain species in llama serum, confirming the presence of three IgG2 subisotypes. Two IgG2 subisotypes were detected in alpaca and guanaco sera. The MAbs detected llama serum IgGs when they were bound to antigen in enzyme-linked immunosorbent assays and were used to discern among isotypes induced during infection with a parasitic nematode. Diseased animals, infected with Parelaphostrongylus tenuis, did not produce antigen-specific HCAbs; rather, they produced the conventional isotype, IgG1, exclusively. Our data document the utility of these MAbs in functional and physiologic investigations of the immune systems of New World camelids.

  4. Patterns of MHC-G-Like and MHC-B Diversification in New World Monkeys.

    Directory of Open Access Journals (Sweden)

    Juan S Lugo

    Full Text Available The MHC class I (MHC-I region in New World monkeys (Platyrrhini has remained relatively understudied. To evaluate the diversification patterns and transcription behavior of MHC-I in Platyrrhini, we first analyzed public genomic sequences from the MHC-G-like subregion in Saimiri boliviensis, Ateles geoffroyi and Callicebus moloch, and from the MHC-B subregion in Saimiri boliviensis. While S. boliviensis showed multiple copies of both MHC-G-like (10 and -B (15 loci, A. geoffroyi and C. moloch had only three and four MHC-G-like genes, respectively, indicating that not all Platyrrhini species have expanded their MHC-I loci. We then sequenced MHC-G-like and -B cDNAs from nine Platyrrhini species, recovering two to five unique cDNAs per individual for both loci classes. In two Saguinus species, however, no MHC-B cDNAs were found. In phylogenetic trees, MHC-G-like cDNAs formed genus-specific clusters whereas the MHC-B cDNAs grouped by Platyrrhini families, suggesting a more rapid diversification of the former. Furthermore, cDNA sequencing in 12 capuchin monkeys showed that they transcribe at least four MHC-G-like and five MHC-B polymorphic genes, showing haplotypic diversity for gene copy number and signatures of positive natural selection at the peptide binding region. Finally, a quantitative index for MHC:KIR affinity was proposed and tested to predict putative interacting pairs. Altogether, our data indicate that i MHC-I genes has expanded differentially among Platyrrhini species, ii Callitrichinae (tamarins and marmosets MHC-B loci have limited or tissue-specific expression, iii MHC-G-like genes have diversified more rapidly than MHC-B genes, and iv the MHC-I diversity is generated mainly by genetic polymorphism and gene copy number variation, likely promoted by natural selection for ligand binding.

  5. Dynein Heavy Chain, Encoded by Two Genes in Agaricomycetes, Is Required for Nuclear Migration in Schizophyllum commune.

    Directory of Open Access Journals (Sweden)

    Melanie Brunsch

    Full Text Available The white-rot fungus Schizophyllum commune (Agaricomycetes was used to study the cell biology of microtubular trafficking during mating interactions, when the two partners exchange nuclei, which are transported along microtubule tracks. For this transport activity, the motor protein dynein is required. In S. commune, the dynein heavy chain is encoded in two parts by two separate genes, dhc1 and dhc2. The N-terminal protein Dhc1 supplies the dimerization domain, while Dhc2 encodes the motor machinery and the microtubule binding domain. This split motor protein is unique to Basidiomycota, where three different sequence patterns suggest independent split events during evolution. To investigate the function of the dynein heavy chain, the gene dhc1 and the motor domain in dhc2 were deleted. Both resulting mutants were viable, but revealed phenotypes in hyphal growth morphology and mating behavior as well as in sexual development. Viability of strain Δdhc2 is due to the higher expression of kinesin-2 and kinesin-14, which was proven via RNA sequencing.

  6. Analyses of Dynein Heavy Chain Mutations Reveal Complex Interactions Between Dynein Motor Domains and Cellular Dynein Functions

    Science.gov (United States)

    Sivagurunathan, Senthilkumar; Schnittker, Robert R.; Razafsky, David S.; Nandini, Swaran; Plamann, Michael D.; King, Stephen J.

    2012-01-01

    Cytoplasmic dynein transports cargoes for a variety of crucial cellular functions. However, since dynein is essential in most eukaryotic organisms, the in-depth study of the cellular function of dynein via genetic analysis of dynein mutations has not been practical. Here, we identify and characterize 34 different dynein heavy chain mutations using a genetic screen of the ascomycete fungus Neurospora crassa, in which dynein is nonessential. Interestingly, our studies show that these mutations segregate into five different classes based on the in vivo localization of the mutated dynein motors. Furthermore, we have determined that the different classes of dynein mutations alter vesicle trafficking, microtubule organization, and nuclear distribution in distinct ways and require dynactin to different extents. In addition, biochemical analyses of dynein from one mutant strain show a strong correlation between its in vitro biochemical properties and the aberrant intracellular function of that altered dynein. When the mutations were mapped to the published dynein crystal structure, we found that the three-dimensional structural locations of the heavy chain mutations were linked to particular classes of altered dynein functions observed in cells. Together, our data indicate that the five classes of dynein mutations represent the entrapment of dynein at five separate points in the dynein mechanochemical and transport cycles. We have developed N. crassa as a model system where we can dissect the complexities of dynein structure, function, and interaction with other proteins with genetic, biochemical, and cell biological studies. PMID:22649085

  7. A cell-based MHC stabilization assay for the detection of peptide binding to the canine classical class I molecule, DLA-88.

    Science.gov (United States)

    Ross, Peter; Holmes, Jennifer C; Gojanovich, Gregory S; Hess, Paul R

    2012-12-15

    Identifying immunodominant CTL epitopes is essential for studying CD8+ T-cell responses in populations, but remains difficult, as peptides within antigens typically are too numerous for all to be synthesized and screened. Instead, to facilitate discovery, in silico scanning of proteins for sequences that match the motif, or binding preferences, of the restricting MHC class I allele - the largest determinant of immunodominance - can be used to predict likely candidates. The high false positive rate with this analysis ideally requires binding confirmation, which is obtained routinely by an assay using cell lines such as RMA-S that have defective transporter associated with antigen processing (TAP) machinery, and consequently, few surface class I molecules. The stabilization and resultant increased life-span of peptide-MHC complexes on the cell surface by the addition of true binders validates their identity. To determine whether a similar assay could be developed for dogs, we transfected a prevalent class I allele, DLA-88*50801, into RMA-S. In the BARC3 clone, the recombinant heavy chain was associated with murine β2-microglobulin, and importantly, could differentiate motif-matched and -mismatched peptides by surface MHC stabilization. This work demonstrates the potential to use RMA-S cells transfected with canine alleles as a tool for CTL epitope discovery in this species. Copyright © 2012 Elsevier B.V. All rights reserved.

  8. SNPs within the beta myosin heavy chain (MYH7 and the pyruvate kinase muscle (PKM2 genes in horse

    Directory of Open Access Journals (Sweden)

    Vincenzo Russo

    2010-01-01

    Full Text Available Two highly expressed skeletal muscle genes (the MYH7 gene encoding the myosin heavy chain slow/β-cardiac isoform and the PKM2 gene encoding the pyruvate kinase muscle isoforms were investigated with the objective to identify DNA markers in horses. A panel of DNA samples from different horse breeds was analysed using a PCR-single strand conformation polymorphism (SSCP approach. Four and two alleles were identified for the MYH7 and PKM2 loci, respectively. Mendelian inheritance of alleles of the two investigated genes was confirmed analysing horse families. Sequencing of PCR products obtained from the MYH7 and PKM2 genes made it possible to characterise two SSCP alleles for each gene. The polymorphisms found in the MYH7 and PKM2 genes were further studied in 61 and 68 horses of three (Italian Heavy Draught Horse, Italian Saddler and Murgese and five (Franches-Montagnes, Haflinger, Italian Heavy Draught Horse, Murgese and Standardbred breeds, respectively. Allele frequencies of the two loci varied among the considered breeds. The SNPs discovery in MYH7 and PKM2 genes makes it possible to locate new molecular markers to ECA1. The identified markers could be used in association analysis with performance traits in horses.

  9. Somatic hypermutation and junctional diversification at Ig heavy chain loci in the nurse shark.

    Science.gov (United States)

    Malecek, Karolina; Brandman, Julie; Brodsky, Jennie E; Ohta, Yuko; Flajnik, Martin F; Hsu, Ellen

    2005-12-15

    We estimate there are approximately 15 IgM H chain loci in the nurse shark genome and have characterized one locus. It consists of one V, two D, and one J germline gene segments, and the constant (C) region can be distinguished from all of the others by a unique combination of restriction endonuclease sites in Cmu2. On the basis of these Cmu2 markers, 22 cDNA clones were selected from an epigonal organ cDNA library from the same individual; their C region sequences proved to be the same up to the polyadenylation site. With the identification of the corresponding germline gene segments, CDR3 from shark H chain rearrangements could be analyzed precisely, for the first time. Considerable diversity was generated by trimming and N addition at the three junctions and by varied recombination patterns of the two D gene segments. The cDNA sequences originated from independent rearrangements events, and most carried both single and contiguous substitutions. The 53 point mutations occurred with a bias for transition changes (53%), whereas the 78 tandem substitutions, mostly 2-4 bp long, do not (36%). The nature of the substitution patterns is the same as for mutants from six loci of two nurse shark L chain isotypes, showing that somatic hypermutation events are very similar at both H and L chain genes in this early vertebrate. The cis-regulatory elements targeting somatic hypermutation must have already existed in the ancestral Ig gene, before H and L chain divergence.

  10. MHC Class II epitope predictive algorithms

    DEFF Research Database (Denmark)

    Nielsen, Morten; Lund, Ole; Buus, S

    2010-01-01

    Major histocompatibility complex class II (MHC-II) molecules sample peptides from the extracellular space, allowing the immune system to detect the presence of foreign microbes from this compartment. To be able to predict the immune response to given pathogens, a number of methods have been...... developed to predict peptide-MHC binding. However, few methods other than the pioneering TEPITOPE/ProPred method have been developed for MHC-II. Despite recent progress in method development, the predictive performance for MHC-II remains significantly lower than what can be obtained for MHC-I. One reason...

  11. Flow cytometric analysis of immunoglobulin heavy chain expression in B-cell lymphoma and reactive lymphoid hyperplasia

    Science.gov (United States)

    Grier, David D; Al-Quran, Samer Z; Cardona, Diana M; Li, Ying; Braylan, Raul C

    2012-01-01

    The diagnosis of B-cell lymphoma (BCL) is often dependent on the detection of clonal immunoglobulin (Ig) light chain expression. In some BCLs, the determination of clonality based on Ig light chain restriction may be difficult. The aim of our study was to assess the utility of flow cytometric analysis of surface Ig heavy chain (HC) expression in lymphoid tissues in distinguishing lymphoid hyperplasias from BCLs, and also differentiating various BCL subtypes. HC expression on B-cells varied among different types of hyperplasias. In follicular hyperplasia, IgM and IgD expression was high in mantle cells while germinal center cells showed poor HC expression. In other hyperplasias, B cell compartments were blurred but generally showed high IgD and IgM expression. Compared to hyperplasias, BCLs varied in IgM expression. Small lymphocytic lymphomas had lower IgM expression than mantle cell lymphomas. Of importance, IgD expression was significantly lower in BCLs than in hyperplasias, a finding that can be useful in differentiating lymphoma from reactive processes. PMID:22400070

  12. Physical linkage of a human immunoglobulin heavy chain variable region gene segment to diversity and joining region elements

    International Nuclear Information System (INIS)

    Schroeder, H.W. Jr.; Walter, M.A.; Hofker, M.H.; Ebens, A.; Van Dijk, K.W.; Liao, L.C.; Cox, D.W.; Milner, E.C.B.; Perlmutter, R.M.

    1988-01-01

    Antibody genes are assembled from a series of germ-line gene segments that are juxtaposed during the maturation of B lymphocytes. Although diversification of the adult antibody repertoire results in large part from the combinatorial joining of these gene segments, a restricted set of antibody heavy chain variable (V H ), diversity (D H ), and joining (J H ) region gene segments appears preferentially in the human fetal repertoire. The authors report here that one of these early-expressed V H elements (termed V H 6) is the most 3' V H gene segment, positioned 77 kilobases on the 5' side of the J H locus and immediately adjacent to a set of previously described D H sequences. In addition to providing a physical map linking human V H , D H , and J H elements, these results support the view that the programmed development of the antibody V H repertoire is determined in part by the chromosomal position of these gene segments

  13. Genotype phenotype correlations of cardiac beta-myosin heavy chain mutations in Indian patients with hypertrophic and dilated cardiomyopathy

    DEFF Research Database (Denmark)

    Rai, Taranjit Singh; Ahmad, Shamim; Bahl, Ajay

    2009-01-01

    The aim of the current study was to determine the frequency of mutations in the beta-myosin heavy chain gene (MYH7) in a cohort of hypertrophic cardiomyopathy (HCM) and dilated cardiomyopathy (DCM) and their families, and to investigate correlations between genotype and phenotype. About 130...... consecutive patients diagnosed with HCM or DCM (69 with HCM and 61 with DCM) attending the cardiology clinic of Post Graduate Institute of Medical Education and Research were screened for mutations in the MYH7 gene. The control group for genetic studies consisted of 100 healthy subjects. We report 14...... mutations in 6 probands (5 probands in HCM and 1 proband in DCM) and their family members. Out of these 6 mutations, 3 are new and are being reported for the first time. One known mutation (p.Gly716Arg) was found to be "de novo" which resulted in severe asymmetric septal hypertrophy (31 mm) and resulted...

  14. Position of nonmuscle myosin heavy chain IIA (NMMHC-IIA) mutations predicts the natural history of MYH9-related disease

    DEFF Research Database (Denmark)

    Pecci, A.; Panza, E.; Pujol-Moix, N.

    2008-01-01

    MYH9-related disease (MYH9-RD) is a rare autosomal-dominant disorder caused by mutations in MYH9, the gene for the heavy chain of nonmuscle myosin IIA (NMMHC-IIA). All patients present from birth with macrothrombocytopenia, but in infancy or adult life, some of them develop sensorineural deafness...... to 50 unrelated pedigrees. The risk of noncongenital manifestations associated with different genotypes was estimated over time by event-free survival analysis. We demonstrated that all subjects with mutations in the motor domain of NMMHC-IIA present with severe thrombocytopenia and develop nephritis...... and deafness before the age of 40 years, while those with mutations in the tail domain have a much lower risk of noncongenital complications and significantly higher platelet counts. We also evaluated the clinical course of patients with mutations in the four most frequently affected residues of NMMHC...

  15. The optimization of peptide cargo bound to MHC class I molecules by the peptide-loading complex.

    Science.gov (United States)

    Elliott, Tim; Williams, Anthony

    2005-10-01

    Major histocompatibility complex (MHC) class I complexes present peptides from both self and foreign intracellular proteins on the surface of most nucleated cells. The assembled heterotrimeric complexes consist of a polymorphic glycosylated heavy chain, non-polymorphic beta(2) microglobulin, and a peptide of typically nine amino acids in length. Assembly of the class I complexes occurs in the endoplasmic reticulum and is assisted by a number of chaperone molecules. A multimolecular unit termed the peptide-loading complex (PLC) is integral to this process. The PLC contains a peptide transporter (transporter associated with antigen processing), a thiooxido-reductase (ERp57), a glycoprotein chaperone (calreticulin), and tapasin, a class I-specific chaperone. We suggest that class I assembly involves a process of optimization where the peptide cargo of the complex is edited by the PLC. Furthermore, this selective peptide loading is biased toward peptides that have a longer off-rate from the assembled complex. We suggest that tapasin is the key chaperone that directs this action of the PLC with secondary contributions from calreticulin and possibly ERp57. We provide a framework model for how this may operate at the molecular level and draw parallels with the proposed mechanism of action of human leukocyte antigen-DM for MHC class II complex optimization.

  16. Genetic stability of gene targeted immunoglobulin loci. I. Heavy chain isotype exchange induced by a universal gene replacement vector.

    Science.gov (United States)

    Kardinal, C; Selmayr, M; Mocikat, R

    1996-11-01

    Gene targeting at the immunoglobulin loci of B cells is an efficient tool for studying immunoglobulin expression or generating chimeric antibodies. We have shown that vector integration induced by human immunoglobulin G1 (IgG1) insertion vectors results in subsequent vector excision mediated by the duplicated target sequence, whereas replacement events which could be induced by the same constructs remain stable. We could demonstrate that the distribution of the vector homology strongly influences the genetic stability obtained. To this end we developed a novel type of a heavy chain replacement vector making use of the heavy chain class switch recombination sequence. Despite the presence of a two-sided homology this construct is universally applicable irrespective of the constant gene region utilized by the B cell. In comparison to an integration vector the frequency of stable incorporation was strongly increased, but we still observed vector excision, although at a markedly reduced rate. The latter events even occurred with circular constructs. Linearization of the construct at various sites and the comparison with an integration vector that carries the identical homology sequence, but differs in the distribution of homology, revealed the following features of homologous recombination of immunoglobulin genes: (i) the integration frequency is only determined by the length of the homology flank where the cross-over takes place; (ii) a 5' flank that does not meet the minimum requirement of homology length cannot be complemented by a sufficient 3' flank; (iii) free vector ends play a role for integration as well as for replacement targeting; (iv) truncating recombination events are suppressed in the presence of two flanks. Furthermore, we show that the switch region that was used as 3' flank is non-functional in an inverted orientation.

  17. Bioaccumulation of heavy metals both in wild and mariculture food chains in Daya Bay, South China

    Science.gov (United States)

    Qiu, Yao-Wen

    2015-09-01

    Bioaccumulation and trophic transfer of heavy metals both in the natural marine ecosystem (seawater, sediment, coral reef, phytoplankton, macrophyte, shrimp, crab, shellfish, planktivorous and carnivorous fish) and in the mariculture ecosystem (compound feed, trash fish, farmed pompano and snapper) were studied at Daya Bay, a typical subtropical bay in Southern China. The levels of Cu, Zn, Pb and Cd in sediment were 11.7, 10.2, 53.8 and 2.8 times than those in coral reef, respectively. Pb and Zn levels were markedly higher in phytoplankton than in macrophyte, probably caused by the larger specific surface area in phytoplankton. The highest levels of Zn (98.1), Pb (1.87) and Cd (5.11 μg g-1 dw) in wild organisms were all found in clam (Veremolpa scabra), indicating that these metals were apt to bioaccumulate in shellfish. The average concentrations of Cu, Zn, Pb and Cd in wild fish were 3.7, 2.1, 0.4 and 22.2 times than those in farmed fish, confirming the "growth dilution" hypothesis in farmed fish. Heavy metal bioconcentration factors (BCFs) in algae, bioaccumulation factors (BAFs) in wild species and transfer factors (TFs) in organism were calculated and discussed. The results suggested that biologically essential Cu and Zn were easier to accumulate in fish than non-essential Cd. Concentrations of Cu, Zn and Cd were several times higher in wild fish than in farmed fish whereas the opposite was observed for Pb. This metal also showed the highest transfer factor from food, which means that special attention must be given to fish feed production in relation to metal contamination.

  18. Plasma vitamin D-binding protein (GC) factors, immunoglobulin G heavy chain (GM) allotypes and immunoglobulin kappa light chain (KM1) allotype in patients with sarcoidosis and in healthy control subjects

    DEFF Research Database (Denmark)

    Milman, Nils; Thymann, Mariann; Graudal, Niels

    2002-01-01

    BACKGROUND AND AIM: Sarcoidosis is an immune disease with abnormalities in the production of vitamin D and immunoglobulins. The aim was to examine whether the distribution of plasma vitamin D-binding protein = group-specific component (GC) allotypes, immunoglobulin G heavy chain (GM) allotypes an...

  19. Immunoglobulin diversification in B cell malignancies: internal splicing of heavy chain variable region as a by-product of somatic hypermutation

    NARCIS (Netherlands)

    Bende, R. J.; Aarts, W. M.; Pals, S. T.; van Noesel, C. J. M.

    2002-01-01

    In this study we describe alternative splicing of somatically mutated immunoglobulin (Ig) variable heavy chain (V-H) genes in three distinct primary B cell non-Hodgkin's lymphomas (B-NHL). In two V4-34 expressing lymphomas, ie a post-germinal center type B cell chronic lymphocytic leukemia (B-CLL)

  20. [Changes in titin and myosin heavy chain isoform composition in skeletal muscles of Mongolian gerbil (Meriones unguiculatus) after 12-day spaceflight].

    Science.gov (United States)

    Okuneva, A D; Vikhliantsev, I M; Shpagina, M D; Rogachevskiĭ, V V; Khutsian, S S; Poddubnaia, Z A; Grigor'ev, A I

    2012-01-01

    Changes of titin and myosin heavy chain isoform composition in skeletal muscles (m. soleus, m. gastrocnemius, m. tibialis anterior, m. psoas major) in Mongolian Gerbil (Meriones unguiculatus ) were investigated after 12-day spaceflight on board of Russian space vehicle "Foton-M3". In m. psoas and m. soleus in the gerbils from "Flight" group the expected increase in the content of fast myosin heavy chain isoforms (IIxd and IIa, respectively) were observed. No significant differences were found in the content of IIxd and IIa isoforms of myosin heavy chain in m. tibialis anterior in the gerbils from control group as compared to that in "Flight" group. An unexpected increase in the content of slow myosin heavy chain I isoform and a decrease in the content of fast IIx/d isoform in m. gastrocnemius of the gerbils from "Flight" group were observed. In skeletal muscles of the gerbils from "Flight" group the relative content of titin N2A-isoform was reduced (by 1,2-1,7 times), although the content of its NT-isoform, which was revealed in striated muscles of mammals in our experiments earlier, remained the same. When the content of titin N2A-isoform was decreased, no predictable abnormalities in sarcomeric structure and contractile ability of skeletal muscles in the gerbils from "Flight" group were found. An assumption on the leading role of titin NT-isoform in maintenance of structural and functional properties of striated muscles of mammals was made.

  1. 3D Architecture, dynamics as well as functional implications of genome organization of the Prader-Willi/Angelmann syndrome region & the Immunoglobin Heavy-Chain locus

    NARCIS (Netherlands)

    T.A. Knoch (Tobias)

    2008-01-01

    textabstractThe general 3D architecture of the immunoglobin heavy-chain (Igh) locus was determined by a novel interdisciplinary combination of high-resolution FISH and high-resolution epifluorescence spectral distance microscopy with analytical analysis, computer simulations, as well as

  2. Production of bifunctional proteins by Aspergillus awamori: Llama variable heavy chain antibody fragment (V-HH) R9 coupled to Arthromyces ramosus peroxidase (ARP)

    NARCIS (Netherlands)

    Joosten, V.; Roelofs, M.S.; Dries, van den N.; Goosen, T.; Verrips, C.T.; Hondel, van den C.A.M.J.J.; Lokman, B.C.

    2005-01-01

    The Arthromyces ramosus peroxidase gene (arp) was genetically fused to either the 5'- or 3'-terminal ends of the gene encoding llama variable heavy chain antibody fragment V-HH R9, resulting in the fusion expression cassettes ARP-R9 or R9-ARP. Aspergillus awamori transformants were obtained which

  3. Production of bifunctional proteins by Aspergillus awamori: Llama variable heavy chain antibody fragment (VHH) R9 coupled to Arthromyces ramosus peroxidase (ARP)

    NARCIS (Netherlands)

    Joosten, V.; Roelofs, M.S.; Dries, N. van den; Goosen, T.; Verrips, C.T.; Hondel, C.A.M.J.J. van den; Lokman, B.C.

    2005-01-01

    The Arthromyces ramosus peroxidase gene (arp) was genetically fused to either the 5′- or 3′-terminal ends of the gene encoding llama variable heavy chain antibody fragment VHH R9, resulting in the fusion expression cassettes ARP-R9 or R9-ARP. Aspergillus awamori transformants were obtained which

  4. Metastasis-associated protein Mts1 (S100A4) inhibits CK2-mediated phosphorylation and self-assembly of the heavy chain of nonmuscle myosin

    DEFF Research Database (Denmark)

    Kriajevska, M; Bronstein, I B; Scott, D J

    2000-01-01

    a regulatory role in the myosin assembly. In the presence of calcium, Mts1 binds at the C-terminal end of the myosin heavy chain close to the site of phosphorylation by protein kinase CK2 (Ser1944). In the present study, we have shown that interaction of Mts1 with the human platelet myosin or C...

  5. The evolution of multiple isotypic IgM heavy chain genes in the shark.

    Science.gov (United States)

    Lee, Victor; Huang, Jing Li; Lui, Ming Fai; Malecek, Karolina; Ohta, Yuko; Mooers, Arne; Hsu, Ellen

    2008-06-01

    The IgM H chain gene organization of cartilaginous fishes consists of 15-200 miniloci, each with a few gene segments (V(H)-D1-D2-J(H)) and one C gene. This is a gene arrangement ancestral to the complex IgH locus that exists in all other vertebrate classes. To understand the molecular evolution of this system, we studied the nurse shark, which has relatively fewer loci, and characterized the IgH isotypes for organization, functionality, and the somatic diversification mechanisms that act upon them. Gene numbers differ slightly between individuals ( approximately 15), but five active IgM subclasses are always present. Each gene undergoes rearrangement that is strictly confined within the minilocus; in B cells there is no interaction between adjacent loci located > or =120 kb apart. Without combinatorial events, the shark IgM H chain repertoire is based on junctional diversity and, subsequently, somatic hypermutation. We suggest that the significant contribution by junctional diversification reflects the selected novelty introduced by RAG in the early vertebrate ancestor, whereas combinatorial diversity coevolved with the complex translocon organization. Moreover, unlike other cartilaginous fishes, there are no germline-joined VDJ at any nurse shark mu locus, and we suggest that such genes, when functional, are species-specific and may have specialized roles. With an entire complement of IgM genes available for the first time, phylogenetic analyses were performed to examine how the multiple Ig loci evolved. We found that all domains changed at comparable rates, but V(H) appears to be under strong positive selection for increased amino acid sequence diversity, and surprisingly, so does Cmicro2.

  6. Measurements on Pb27+ Sources for the CERN Heavy Ion Injection Chain

    CERN Document Server

    Chamings, J A

    2004-01-01

    CERN, the world's largest particle physics laboratory near Geneva, is currently in the process of building the Large Hadron Collider (LHC). Lead-208 will be used in this accelerator and to meet the injection requirements much work is required to find a suitable and reliable heavy ion source. The work in this report covers two ion sources, the Laser Ion Source (LIS), and the Electron Cyclotron Resonance Ion Source (ECRIS). An emittance measurement, using a pepper pot and CCD camera, was completed on the recently re-installed LIS, measured and analysed to be 140mm.mrad un-normalised and 0.8mm.mrad normalised 4rms for the maximum intensity charge state, Pb27+. A Visual Basic Program was modified to allow Charge State Distribution (CSD) and other scans of the ECRIS at CERN to be taken. Chapter 5 presents the results of the CSD scans taken. This program provided a new method to take 1 dimensional transverse beam profiles. From this a direct emittance measurement was formed for the first time since the source was o...

  7. MHC class II expression in lung cancer.

    Science.gov (United States)

    He, Yayi; Rozeboom, Leslie; Rivard, Christopher J; Ellison, Kim; Dziadziuszko, Rafal; Yu, Hui; Zhou, Caicun; Hirsch, Fred R

    2017-10-01

    Immunotherapy is an exciting development in lung cancer research. In this study we described major histocompatibility complex (MHC) Class II protein expression in lung cancer cell lines and patient tissues. We studied MHC Class II (DP, DQ, DR) (CR3/43, Abcam) protein expression in 55 non-small cell lung cancer (NSCLC) cell lines, 42 small cell lung cancer (SCLC) cell lines and 278 lung cancer patient tissues by immunohistochemistry (IHC). Seven (12.7%) NSCLC cell lines were positive for MHC Class II. No SCLC cell lines were found to be MHC Class II positive. We assessed 139 lung cancer samples available in the Hirsch Lab for MHC Class II. There was no positive MHC Class II staining on SCLC tumor cells. MHC Class II expression on TILs in SCLC was significantly lower than that on TILs in NSCLC (P<0.001). MHC Class II was also assessed in an additional 139 NSCLC tumor tissues from Medical University of Gdansk, Poland. Patients with positive staining of MHC Class II on TILs had longer regression-free survival (RFS) and overall survival (OS) than those whose TILs were MHC Class II negative (2.980 years, 95% CI 1.628-4.332 vs. 1.050 years, 95% CI 0.556-1.554, P=0.028) (3.230 years, 95% CI 2.617-3.843 vs. 1.390 years, 95% CI 0.629-2.151, P=0.014). MHC Class II was expressed both in NSCLC cell lines and tissues. However, MHC Class II was not detected in SCLC cell lines or tissue tumor cells. MHC Class II expression was lower on SCLC TILs than on NSCLC TILs. Loss of expression of MHC Class II on SCLC tumor cells and reduced expression on SCLC TILs may be a means of escaping anti-cancer immunity. Higher MHC Class II expression on TILs was correlated with better prognosis in patients with NSCLC. Copyright © 2017. Published by Elsevier B.V.

  8. Surface mu heavy chain signals down-regulation of the V(D)J-recombinase machinery in the absence of surrogate light chain components.

    Science.gov (United States)

    Galler, Gunther R; Mundt, Cornelia; Parker, Mathew; Pelanda, Roberta; Mårtensson, Inga-Lill; Winkler, Thomas H

    2004-06-07

    Early B cell development is characterized by stepwise, ordered rearrangement of the immunoglobulin (Ig) heavy (HC) and light (LC) chain genes. Only one of the two alleles of these genes is used to produce a receptor, a phenomenon referred to as allelic exclusion. It has been suggested that pre-B cell receptor (pre-BCR) signals are responsible for down-regulation of the VDJH-recombinase machinery (Rag1, Rag2, and terminal deoxynucleotidyl transferase [TdT]), thereby preventing further rearrangement on the second HC allele. Using a mouse model, we show that expression of an inducible muHC transgene in Rag2-/- pro-B cells induces down-regulation of the following: (a) TdT protein, (b) a transgenic green fluorescent protein reporter reflecting endogenous Rag2 expression, and (c) Rag1 primary transcripts. Similar effects were also observed in the absence of surrogate LC (SLC) components, but not in the absence of the signaling subunit Ig-alpha. Furthermore, in wild-type mice and in mice lacking either lambda5, VpreB1/2, or the entire SLC, the TdT protein is down-regulated in muHC+LC- pre-B cells. Surprisingly, muHC without LC is expressed on the surface of pro-/pre-B cells from lambda5-/-, VpreB1-/-VpreB2-/-, and SLC-/- mice. Thus, SLC or LC is not required for muHC cell surface expression and signaling in these cells. Therefore, these findings offer an explanation for the occurrence of HC allelic exclusion in mice lacking SLC components.

  9. MHC variability in heritage breeds of chickens.

    Science.gov (United States)

    Fulton, J E; Lund, A R; McCarron, A M; Pinegar, K N; Korver, D R; Classen, H L; Aggrey, S; Utterbach, C; Anthony, N B; Berres, M E

    2016-02-01

    The chicken Major Histocompatibility Complex (MHC) is very strongly associated with disease resistance and thus is a very important region of the chicken genome. Historically, MHC (B locus) has been identified by the use of serology with haplotype specific alloantisera. These antisera can be difficult to produce and frequently cross-react with multiple haplotypes and hence their application is generally limited to inbred and MHC-defined lines. As a consequence, very little information about MHC variability in heritage chicken breeds is available. DNA-based methods are now available for examining MHC variability in these previously uncharacterized populations. A high density SNP panel consisting of 101 SNP that span a 230,000 bp region of the chicken MHC was used to examine MHC variability in 17 heritage populations of chickens from five universities from Canada and the United States. The breeds included 6 heritage broiler lines, 3 Barred Plymouth Rock, 2 New Hampshire and one each of Rhode Island Red, Light Sussex, White Leghorn, Dark Brown Leghorn, and 2 synthetic lines. These heritage breeds contained from one to 11 haplotypes per line. A total of 52 unique MHC haplotypes were found with only 10 of them identical to serologically defined haplotypes. Furthermore, nine MHC recombinants with their respective parental haplotypes were identified. This survey confirms the value of these non-commercially utilized lines in maintaining genetic diversity. The identification of multiple MHC haplotypes and novel MHC recombinants indicates that diversity is being generated and maintained within these heritage populations. © 2016 Poultry Science Association Inc.

  10. Endocytosis-independent function of clathrin heavy chain in the control of basal NF-κB activation.

    Directory of Open Access Journals (Sweden)

    Man Lyang Kim

    Full Text Available BACKGROUND: Nuclear factor-κB (NF-κB is a transcription factor that regulates the transcription of genes involved in a variety of biological processes, including innate and adaptive immunity, stress responses and cell proliferation. Constitutive or excessive NF-κB activity has been associated with inflammatory disorders and higher risk of cancer. In contrast to the mechanisms controlling inducible activation, the regulation of basal NF-κB activation is not well understood. Here we test whether clathrin heavy chain (CHC contributes to the regulation of basal NF-κB activity in epithelial cells. METHODOLOGY: Using RNA interference to reduce endogenous CHC expression, we found that CHC is required to prevent constitutive activation of NF-κB and gene expression. Immunofluorescence staining showed constitutive nuclear localization of the NF-κB subunit p65 in absence of stimulation after CHC knockdown. Elevated basal p65 nuclear localization is caused by constitutive phosphorylation and degradation of inhibitor of NF-κB alpha (IκBα through an IκB kinase α (IKKα-dependent mechanism. The role of CHC in NF-κB signaling is functionally relevant as constitutive expression of the proinflammatory chemokine interleukin-8 (IL-8, whose expression is regulated by NF-κB, was found after CHC knockdown. Disruption of clathrin-mediated endocytosis by chemical inhibition or depletion of the μ2-subunit of the endocytosis adaptor protein AP-2, and knockdown of clathrin light chain a (CHLa, failed to induce constitutive NF-κB activation and IL-8 expression, showing that CHC acts on NF-κB independently of endocytosis and CLCa. CONCLUSIONS: We conclude that CHC functions as a built-in molecular brake that ensures a tight control of basal NF-κB activation and gene expression in unstimulated cells. Furthermore, our data suggest a potential link between a defect in CHC expression and chronic inflammation disorder and cancer.

  11. Innate lymphoid cells and the MHC.

    Science.gov (United States)

    Robinette, M L; Colonna, M

    2016-01-01

    Innate lymphoid cells (ILCs) are a new class of immune cells that include natural killer (NK) cells and appear to be the innate counterparts to CD4(+) helper T cells and CD8(+) cytotoxic T cells based on developmental and functional similarities. Like T cells, both NK cells and other ILCs also show connections to the major histocompatibility complex (MHC). In human and mouse, NK cells recognize and respond to classical and nonclassical MHC I molecules as well as structural homologues, whereas mouse ILCs have recently been shown to express MHC II. We describe the history of MHC I recognition by NK cells and discuss emerging roles for MHC II expression by ILC subsets, making comparisons between both mouse and human when possible. © 2015 John Wiley & Sons A/S. Published by John Wiley & Sons Ltd.

  12. Activity modulation of microbial enzymes by llama (Lama glama) heavy-chain polyclonal antibodies during in vivo immune responses.

    Science.gov (United States)

    Ferrari, A; Weill, F S; Paz, M L; Cela, E M; González Maglio, D H; Leoni, J

    2012-03-01

    Since they were first described in 1993, it was found that recombinant variable fragments (rVHHs) of heavy-chain antibodies (HCAbs) from Camelidae have unusual biophysical properties, as well as a special ability to interact with epitopes that are cryptic for conventional Abs. It has been assumed that in vivo raised polyclonal HCAbs (pHCAbs) should behave in a similar manner than rVHHs; however, this assumption has not been tested sufficiently. Furthermore, our own preliminary work on a single serum sample from a llama immunized with a β-lactamase, has suggested that pHCAbs have no special ability to down-modulate catalytic activity. In this work, we further explored the interaction of pHCAbs from four llamas raised against two microbial enzymes and analyzed it within a short and a long immunization plan. The relative contribution of pHCAbs to serum titer was found to be low compared with that of the most abundant conventional subisotype (IgG(1)), during the whole immunization schedule. Furthermore, pHCAbs not only failed to inhibit the enzymes, but also activated one of them. Altogether, these results suggest that raising high titer inhibitory HCAbs is not a straightforward strategy - neither as a biotechnological strategy nor in the biological context of an immune response against infection - as raising inhibitory rVHHs.

  13. Dlc1 interaction with non-muscle myosin heavy chain II-A (Myh9 and Rac1 activation

    Directory of Open Access Journals (Sweden)

    Mohammad G. Sabbir

    2016-04-01

    Full Text Available The Deleted in liver cancer 1 (Dlc1 gene codes for a Rho GTPase-activating protein that also acts as a tumour suppressor gene. Several studies have consistently found that overexpression leads to excessive cell elongation, cytoskeleton changes and subsequent cell death. However, none of these studies have been able to satisfactorily explain the Dlc1-induced cell morphological phenotypes and the function of the different Dlc1 isoforms. Therefore, we have studied the interacting proteins associated with the three major Dlc1 transcriptional isoforms using a mass spectrometric approach in Dlc1 overexpressing cells. We have found and validated novel interacting partners in constitutive Dlc1-expressing cells. Our study has shown that Dlc1 interacts with non-muscle myosin heavy chain II-A (Myh9, plectin and spectrin proteins in different multiprotein complexes. Overexpression of Dlc1 led to increased phosphorylation of Myh9 protein and activation of Rac1 GTPase. These data support a role for Dlc1 in induced cell elongation morphology and provide some molecular targets for further analysis of this phenotype.

  14. Improving the accuracy of the structure prediction of the third hypervariable loop of the heavy chains of antibodies.

    KAUST Repository

    Messih, Mario Abdel; Lepore, Rosalba; Marcatili, Paolo; Tramontano, Anna

    2014-01-01

    MOTIVATION: Antibodies are able to recognize a wide range of antigens through their complementary determining regions formed by six hypervariable loops. Predicting the 3D structure of these loops is essential for the analysis and reengineering of novel antibodies with enhanced affinity and specificity. The canonical structure model allows high accuracy prediction for five of the loops. The third loop of the heavy chain, H3, is the hardest to predict because of its diversity in structure, length and sequence composition. RESULTS: We describe a method, based on the Random Forest automatic learning technique, to select structural templates for H3 loops among a dataset of candidates. These can be used to predict the structure of the loop with a higher accuracy than that achieved by any of the presently available methods. The method also has the advantage of being extremely fast and returning a reliable estimate of the model quality. AVAILABILITY AND IMPLEMENTATION: The source code is freely available at http://www.biocomputing.it/H3Loopred/ .

  15. Differences in mitochondrial gene expression profiles, enzyme activities and myosin heavy chain types in yak versus bovine skeletal muscles.

    Science.gov (United States)

    Lin, Y Q; Xu, Y O; Yue, Y; Jin, S Y; Qu, Y; Dong, F; Li, Y P; Zheng, Y C

    2012-08-29

    Hypoxia can affect energy metabolism. We examined gene expression and enzyme activity related to mitochondrial energy metabolism, as well as myosin heavy chain (MyHC) types in yaks (Bos grunniens) living at high altitudes. Real-time quantitative PCR assays indicated that the yak has significantly lower levels of carnitine palmitoyltransferase (CPT) mRNA in the biceps femoris and lower levels of uncoupling protein 3 (UCP3) mRNA in both biceps femoris and longissimus dorsi than in Yellow cattle. No significant differences between yak and Yellow cattle were observed in the activities of mitochondrial β-hydroxyacyl-CoA dehydrogenase, isocitrate dehydrogenase and cytochrome oxidase in the same muscles. Semi-quantitative RT-PCR analysis showed that the MyHC 1 mRNA levels in yak biceps femoris was lower than in Yellow cattle. We conclude that the yak has significantly lower mRNA levels of CPT, UCP3, and MyHC 1 in biceps femoris than in Yellow cattle, suggesting that the yak biceps femoris has lower fatty acid oxidation capacity and greater glycolytic metabolic potential.

  16. Characterisation of myosin heavy chain gene variants in the fast and slow muscle fibres of gammarid amphipods.

    Science.gov (United States)

    Whiteley, N M; Magnay, J L; McCleary, S J; Nia, S Khazraee; El Haj, A J; Rock, J

    2010-10-01

    Recent molecular work has revealed a large diversity of myosin heavy chain (MyHC) gene variants in the abdominal musculature of gammarid amphipods. An unusual truncated MyHC transcript from the loop 1 region (Variant A(3)) was consistently observed in multiple species and populations. The current study aimed to determine whether this MyHC variant is specific to a particular muscle fibre type, as a change in net charge to the loop 1 region of Variant A(3) could be functionally significant. The localisation of different fibre types within the abdominal musculature of several gammarid species revealed that the deep flexor and extensor muscles are fast-twitch muscle fibres. The dorsal superficial muscles were identified as slow fibres and the muscles extrinsic to the pleopods were identified as intermediate fibres. Amplification of loop 1 region mRNA from isolated superficial extensor and deep flexor muscles, and subsequent liquid chromatography and sequence analysis revealed that Variant A(3) was the primary MyHC variant in slow muscles, and the conserved A(1) sequence was the primary variant in fast muscles. The specific role of Variant A(3) in the slow muscles remains to be investigated. 2010 Elsevier Inc. All rights reserved.

  17. Improving the accuracy of the structure prediction of the third hypervariable loop of the heavy chains of antibodies.

    KAUST Repository

    Messih, Mario Abdel

    2014-06-13

    MOTIVATION: Antibodies are able to recognize a wide range of antigens through their complementary determining regions formed by six hypervariable loops. Predicting the 3D structure of these loops is essential for the analysis and reengineering of novel antibodies with enhanced affinity and specificity. The canonical structure model allows high accuracy prediction for five of the loops. The third loop of the heavy chain, H3, is the hardest to predict because of its diversity in structure, length and sequence composition. RESULTS: We describe a method, based on the Random Forest automatic learning technique, to select structural templates for H3 loops among a dataset of candidates. These can be used to predict the structure of the loop with a higher accuracy than that achieved by any of the presently available methods. The method also has the advantage of being extremely fast and returning a reliable estimate of the model quality. AVAILABILITY AND IMPLEMENTATION: The source code is freely available at http://www.biocomputing.it/H3Loopred/ .

  18. MR molecular imaging of tumours using ferritin heavy chain reporter gene expression mediated by the hTERT promoter

    Energy Technology Data Exchange (ETDEWEB)

    Yang, Yan [Third Military Medical University, Department of Radiology, XinQiao Hospital, ChongQing (China); The First Affiliated Hospital of ChengDu Medical College, Department of Radiology, ChengDu (China); Gong, Ming-fu; Yang, Hua; Zhang, Song; Wang, Guang-xian; Su, Tong-sheng; Wen, Li; Zhang, Dong [Third Military Medical University, Department of Radiology, XinQiao Hospital, ChongQing (China)

    2016-11-15

    Using the human telomerase reverse transcriptase (hTERT) promoter and the modified ferritin heavy chain (Fth) reporter gene, reporter gene expression for MRI was examined in telomerase positive and negative tumour cells and xenografts. Activity of the reporter gene expression vector Lenti-hTERT-Fth1-3FLAG-Puro was compared to constitutive CMV-driven expression and to the untransfected parental control in five tumour cell lines: A549, SKOV3, 293T, U2OS and HPDLF. In vitro, transfected cells were evaluated for FLAG-tagged protein expression, iron accumulation and transverse relaxation. In vivo, tumours transduced by lentiviral vector injection were imaged using T2*WI. Changes in tumour signal intensity were validated by histology. Only telomerase positive tumour cells expressed FLAG-tagged Fth and displayed an increase in R2* above the parental control, with a corresponding change in T2*WI. In addition, only telomerase positive tumours, transduced by injection of the reporter gene expression construct, exhibited a change in signal intensity on T2*WI. Tumour histology verified the expression of FLAG-tagged Fth and iron accumulation in telomerase positive tissue. Reporter gene expression for MRI, using the Fth reporter and the hTERT promoter, may be a useful strategy for the non-invasive diagnosis of many types of cancer. (orig.)

  19. High production of llama variable heavy-chain antibody fragment (VHH) fused to various reader proteins by Aspergillus oryzae.

    Science.gov (United States)

    Hisada, Hiromoto; Tsutsumi, Hiroko; Ishida, Hiroki; Hata, Yoji

    2013-01-01

    Llama variable heavy-chain antibody fragment (VHH) fused to four different reader proteins was produced and secreted in culture medium by Aspergillus oryzae. These fusion proteins consisted of N-terminal reader proteins, VHH, and a C-terminal his-tag sequence which facilitated purification using one-step his-tag affinity chromatography. SDS-PAGE analysis of the deglycosylated purified fusion proteins confirmed that the molecular weight of each corresponded to the expected sum of VHH and the respective reader proteins. The apparent high molecular weight reader protein glucoamylase (GlaB) was found to be suitable for efficient VHH production. The GlaB-VHH-His protein bound its antigen, human chorionic gonadotropin, and was detectable by a new ELISA-based method using a coupled assay with glucoamylase, glucose oxidase, peroxidase, maltose, and 3,3',5,5'-tetramethylbenzidine as substrates. Addition of potassium phosphate to the culture medium induced secretion of 0.61 mg GlaB-VHH-His protein/ml culture medium in 5 days.

  20. Imaging of myocardial infarction in dogs and humans using monoclonal antibodies specific for human myosin heavy chains

    International Nuclear Information System (INIS)

    Leger, J.; Chevalier, J.; Larue, C.; Gautier, P.; Planchenault, J.; Aumaitre, E.; Messner, P.; Puech, P.; Saccavini, J.C.; Pau, B.

    1991-01-01

    The use of three different monoclonal antibodies specific for human ventricular myosin heavy chains in the visualization of the location and extent of necrosis in dogs with experimental acute myocardial infarction and in humans is described. Using a classic immunohistochemical method or ex vivo analysis of heart slices in dogs with acute myocardial infarction subjected to intravenous injection of unlabeled antimyosin antibodies or antimyosin antibodies labeled with indium-111, it was observed that all antibody fragments specifically reached the targeted necrotic zone less than 2 h after antibody injection and remained bound for up to 24 h. In a limited but significant number of cases (5 of the 12 humans and 11 of 43 dogs), it was possible to image the necrotic zone in vivo as early as 2 to 4 h after antibody injection. In other cases, individual blood clearance variations retarded or even prevented in vivo necrosis detection. Higher antimyosin fixation values were obtained in the necrotic zones in dogs with a rapid blood clearance relative to that of the other dogs. It is concluded that antimyosin antibodies always reached necrotic areas within 2 h. If blood clearance was rapid, in vivo imaging of the necrotic area was possible 2 to 6 h after necrosis, even in humans. In some cases, however, uncontrolled individual variations in the timing required for sufficient blood clearance hampered this rapid in vivo detection of myocardial necrosis

  1. The peptide-receptive transition state of MHC-1 molecules: Insight from structure and molecular dynamics

    Energy Technology Data Exchange (ETDEWEB)

    Robinson H.; Mage, M.; Dolan, M.; Wang, R.; Boyd, L.; Revilleza, M.; Natarajan, K.; Myers, N.; Hansen, T.; Margulies, D.

    2012-05-01

    MHC class I (MHC-I) proteins of the adaptive immune system require antigenic peptides for maintenance of mature conformation and immune function via specific recognition by MHC-I-restricted CD8(+) T lymphocytes. New MHC-I molecules in the endoplasmic reticulum are held by chaperones in a peptide-receptive (PR) transition state pending release by tightly binding peptides. In this study, we show, by crystallographic, docking, and molecular dynamics methods, dramatic movement of a hinged unit containing a conserved 3(10) helix that flips from an exposed 'open' position in the PR transition state to a 'closed' position with buried hydrophobic side chains in the peptide-loaded mature molecule. Crystallography of hinged unit residues 46-53 of murine H-2L(d) MHC-I H chain, complexed with mAb 64-3-7, demonstrates solvent exposure of these residues in the PR conformation. Docking and molecular dynamics predict how this segment moves to help form the A and B pockets crucial for the tight peptide binding needed for stability of the mature peptide-loaded conformation, chaperone dissociation, and Ag presentation.

  2. A mechanical comparison of linear and double-looped hung supplemental heavy chain resistance to the back squat: a case study.

    Science.gov (United States)

    Neelly, Kurt R; Terry, Joseph G; Morris, Martin J

    2010-01-01

    A relatively new and scarcely researched technique to increase strength is the use of supplemental heavy chain resistance (SHCR) in conjunction with plate weights to provide variable resistance to free weight exercises. The purpose of this case study was to determine the actual resistance being provided by a double-looped versus a linear hung SHCR to the back squat exercise. The linear technique simply hangs the chain directly from the bar, whereas the double-looped technique uses a smaller chain to adjust the height of the looped chain. In both techniques, as the squat descends, chain weight is unloaded onto the floor, and as the squat ascends, chain weight is progressively loaded back as resistance. One experienced and trained male weight lifter (age = 33 yr; height = 1.83 m; weight = 111.4 kg) served as the subject. Plate weight was set at 84.1 kg, approximately 50% of the subject's 1 repetition maximum. The SHCR was affixed to load cells, sampling at a frequency of 500 Hz, which were affixed to the Olympic bar. Data were collected as the subject completed the back squat under the following conditions: double-looped 1 chain (9.6 kg), double-looped 2 chains (19.2 kg), linear 1 chain, and linear 2 chains. The double-looped SHCR resulted in a 78-89% unloading of the chain weight at the bottom of the squat, whereas the linear hanging SHCR resulted in only a 36-42% unloading. The double-looped technique provided nearly 2 times the variable resistance at the top of the squat compared with the linear hanging technique, showing that attention must be given to the technique used to hang SHCR.

  3. Modular Construction of Large Non-Immune Human Antibody Phage-Display Libraries from Variable Heavy and Light Chain Gene Cassettes.

    Science.gov (United States)

    Lee, Nam-Kyung; Bidlingmaier, Scott; Su, Yang; Liu, Bin

    2018-01-01

    Monoclonal antibodies and antibody-derived therapeutics have emerged as a rapidly growing class of biological drugs for the treatment of cancer, autoimmunity, infection, and neurological diseases. To support the development of human antibodies, various display techniques based on antibody gene repertoires have been constructed over the last two decades. In particular, scFv-antibody phage display has been extensively utilized to select lead antibodies against a variety of target antigens. To construct a scFv phage display that enables efficient antibody discovery, and optimization, it is desirable to develop a system that allows modular assembly of highly diverse variable heavy chain and light chain (Vκ and Vλ) repertoires. Here, we describe modular construction of large non-immune human antibody phage-display libraries built on variable gene cassettes from heavy chain and light chain repertoires (Vκ- and Vλ-light can be made into independent cassettes). We describe utility of such libraries in antibody discovery and optimization through chain shuffling.

  4. Detection of clonal B cells in microdissected reactive lymphoproliferations: possible diagnostic pitfalls in PCR analysis of immunoglobulin heavy chain gene rearrangement

    DEFF Research Database (Denmark)

    Zhou, X.G.; Sandvej, K.; Gregersen, Niels

    1999-01-01

    Aims-To evaluate the specificity of standard and fluorescence based (GENESCAN) polymerase chain reaction (PCR) immunoglobulin heavy chain (IgH) gene rearrangement analysis in complete and microdissected paraffin wax embedded sections from lymphoid proliferations. Methods-PCR IgH gene rearrangement...... because of preferential priming or detection of local B cell clones. Data from clonal analysis of small, microdissected or lymphocyte poor samples must be evaluated critically. It is recommended that analyses should be run in parallel on at least two tissue specimens. Only reproducible bands present...

  5. Radioimmunoassay of myosin heavy beta chains in human serum for the evaluation of the size of myocardial infarction: correlation with myocardial Tl-201 SPECT and cardiac angioscintigraphy

    International Nuclear Information System (INIS)

    Facello, A.; Gries, P.; Demangeat, C.; Brunot, B.; Roul, G.; Demangeat, J.L.; Moulichon, M.; Bareiss, P.; Sacrez, A.; Constantinesco, A.

    1990-01-01

    To determine the relationship between serum levels of myosin heavy beta chains assessed by an IRMA technique and other radionuclide and enzymatic parameters in the evaluation of the size of myocardial infarction, we studied 22 patients with acute myocardial infarction. Blood samples taken daily between 1st to 13th day of evolution allow the determination of peak and integral of myosine release that showed a good correlation (p [fr

  6. Cold exposure increases slow-type myosin heavy chain 1 (MyHC1) composition of soleus muscle in rats.

    Science.gov (United States)

    Mizunoya, Wataru; Iwamoto, Yohei; Sato, Yusuke; Tatsumi, Ryuichi; Ikeuchi, Yoshihide

    2014-03-01

    The aim of this study was to examine the effects of cold exposure on rat skeletal muscle fiber type, according to myosin heavy chain (MyHC) isoform and metabolism-related factors. Male Wistar rats (7 weeks old) were housed individually at 4 ± 2°C as a cold-exposed group or at room temperature (22 ± 2°C) as a control group for 4 weeks. We found that cold exposure significantly increased the slow-type MyHC1 content in the soleus muscle (a typical slow-type fiber), while the intermediate-type MyHC2A content was significantly decreased. In contrast to soleus, MyHC composition of extensor digitorum longus (EDL, a typical fast-type fiber) and gastrocnemius (a mix of slow-type and fast-type fibers) muscle did not change from cold exposure. Cold exposure increased mRNA expression of mitochondrial uncoupling protein 3 (UCP3) in both the soleus and EDL. Cold exposure also increased mRNA expression of myoglobin, peroxisome proliferator-activated receptor gamma coactivator 1α (PGC1α) and forkhead box O1 (FOXO1) in the soleus. Upregulation of UCP3 and PGC1α proteins were observed with Western blotting in the gastrocnemius. Thus, cold exposure increased metabolism-related factors in all muscle types that were tested, but MyHC isoforms changed only in the soleus. © 2013 Japanese Society of Animal Science.

  7. Immune recognition of botulinum neurotoxin B: antibody-binding regions on the heavy chain of the toxin.

    Science.gov (United States)

    Dolimbek, Behzod Z; Steward, Lance E; Aoki, K Roger; Atassi, M Zouhair

    2008-02-01

    The purpose of this work was to map the continuous regions recognized by human, horse and mouse anti-botulinum neurotoxin B (BoNT/B) antibodies (Abs). We synthesized a panel of sixty 19-residue peptides (peptide C31 was 24 residues) that overlapped consecutively by 5 residues and together encompassed the entire heavy chain of BoNT/B (H/B, residues 442-1291). Abs from the three host species recognized similar, but not identical, peptides. There were also peptides recognized by two or only by one host species. Where a peptide was recognized by Abs of more than one host species, these Abs were at different levels among the species. Human, horse and mouse Abs bound, although in different amounts, to regions within peptides 736-754, 778-796, 848-866, 932-950, 974-992, 1058-1076 and 1128-1146. Human and horse Abs bound to peptides 890-908 and 1170-1188. Human and mouse Abs recognized peptides 470-488/484-502 overlap, 638-656, 722-740, 862-880, 1030-1048, 1072-1090, 1240-1258 and 1268-1291. We concluded that the antigenic regions localized with the three antisera are quite similar, exhibiting in some cases a small shift to the left or to the right. This is consistent with what is known about protein immune recognition. In the three-dimensional structure, the regions recognized on H/B by anti-BoNT/B Abs occupied surface locations and analysis revealed no correlation between these surface locations and surface electrostatic potential, hydrophilicity, hydrophobicity, or temperature factor. A region that bound mouse Abs overlapped with a recently defined site on BoNT/B that binds to mouse and rat synaptotagmin II, thus providing a molecular explanation for the blocking (protecting) activity of these Abs. The regions thus localized afford candidates for incorporation into a synthetic vaccine design.

  8. Tumor necrosis factor-α attenuates starvation-induced apoptosis through upregulation of ferritin heavy chain in hepatocellular carcinoma cells

    International Nuclear Information System (INIS)

    Kou, Xingrui; Zhao, Qiudong; Zhao, Xue; Li, Rong; Wei, Lixin; Wu, Mengchao; Jing, Yingying; Deng, Weijie; Sun, Kai; Han, Zhipeng; Ye, Fei; Yu, Guofeng; Fan, Qingmin; Gao, Lu

    2013-01-01

    Tumor microenviroment is characteristic of inflammation, ischemia and starvation of nutrient. TNF-α, which is an extraordinarily pleiotropic cytokine, could be an endogenous tumor promoter in some tumor types. The basic objective of this study was to investigate the effects of TNF-α on the cell viability and apoptosis of hepatocellular carcinoma cells under serum starvation, and to identify the molecular mechanisms involved. For this purpose, five different concentrations of TNF-α and two different serum settings (serum-cultured and serum-deprived) were used to investigate the effects of TNF-α on the cell viability and apoptosis of Hep3B and SMMC-7721 cells. TNF-α (10 ng/ml) attenuated serum starvation-induced apoptosis of hepatocellular carcinoma cells, and autophagy conferred this process. BAY11-7082, a specific inhibitor of NF-κB, reversed the suppression of serum starvation-induced apoptosis by TNF-α. Moreover, TNF-α-induced NF-κB transactivation was suppressed by autophagy inhibitor 3-MA. In addition, TNF-α up-regulated Ferritin heavy chain (FHC) transiently by NF-κB activation and FHC levels were correlated with the TNF-α-induced protection against serum starvation-mediated apoptosis of hepatocellular carcinoma cells. Furthermore, FHC-mediated inhibition of apoptosis depended on suppressing ROS accumulation. Our findings suggested that autophagy conferred the TNF-α protection against serum starvation-mediated apoptosis of hepatocellular carcinoma cells, the mechanism involved with the activation of the TNF-α/ NF-κB /FHC signaling pathway

  9. [The value of serum heavy/light chain immunoassay to assess therapeutic response in patients with multiple myeloma].

    Science.gov (United States)

    Yu, X C; Su, W; Zhuang, J L

    2018-04-14

    Objective: To assess the value of immunoglobulin heavy/light chain (HLC) immunoassay on therapeutic response in patients with multiple myeloma(MM). Methods: A total of 45 newly diagnosed MM patients were retrospectively enrolled in Peking Union Medical College Hospital from 2013 to 2016, whose 115 serum samples were consecutively collected. HLC was tested to evaluate response and compare with other methods for M protein detection. Results: ①There were 30 males and 15 females in total of whom the monoclonal immunoglobulin was IgG in 27 (IgGκ∶IgGλ 12∶15) and IgA (IgAκ∶IgAλ 9∶9) in 18. The arerage age of the studied population was 59 (range 43-80) . ② In 34 patients with serum sample at diagnosis, 32 (94.1%) had abnormal HLC ratio (rHLC) while 2 patients with IgG had normal rHLC. The percentages of abnormal rHLC was 81.8% (18/22) at partial response、50.0%(9/18) at very good complete response and 16.0%(4/25) at complete response. ③In 25 patients reaching CR, there were 13 with IgG and 12 with IgA. 4 patients equally split of IgG and IgA had abnormal rHLC at complete response. ④By monitoring the rHLC of some patients consecutively, we found that the remission of rHLC was to some extent behind the remission of SPE and IEF, or even rFLC. Conclusion: Immunoglobulin HLC detection is one feasible method for minimal residual disease detection.

  10. The E5 protein of human papillomavirus type 16 perturbs MHC class II antigen maturation in human foreskin keratinocytes treated with interferon-γ

    International Nuclear Information System (INIS)

    Zhang Benyue; Li Ping; Wang Exing; Brahmi, Zacharie; Dunn, Kenneth W.; Blum, Janice S.; Roman, Ann

    2003-01-01

    Major histocompatibility complex (MHC) class II antigens are expressed on human foreskin keratinocytes (HFKs) following exposure to interferon gamma. The expression of MHC class II proteins on the cell surface may allow keratinocytes to function as antigen-presenting cells and induce a subsequent immune response to virus infection. Invariant chain (Ii) is a chaperone protein which plays an important role in the maturation of MHC class II molecules. The sequential degradation of Ii within acidic endocytic compartments is a key process required for the successful loading of antigenic peptide onto MHC class II molecules. Since human papillomavirus (HPV) 16 E5 can inhibit the acidification of late endosomes in HFKs, the E5 protein may be able to affect proper peptide loading onto the MHC class II molecule. To test this hypothesis, HFKs were infected with either control virus or a recombinant virus expressing HPV16 E5 and the infected cells were subsequently treated with interferon-γ. ELISAs revealed a decrease of MHC class II expression on the surface of E5-expressing cells compared with control virus-infected cells after interferon treatment. Western blot analysis showed that, in cells treated with interferon gamma, E5 could prevent the breakdown of Ii and block the formation of peptide-loaded, SDS-stable mature MHC class II dimers, correlating with diminished surface MHC class II expression. These data suggest that HPV16 E5 may be able to decrease immune recognition of infected keratinocytes via disruption of MHC class II protein function

  11. Breakpoint of an inversion of chromosome 14 in a T-cell leukemia: sequences downstream of the immunoglobulin heavy chain locus are implicated in tumorigenesis

    International Nuclear Information System (INIS)

    Baer, R.; Heppell, A.; Taylor, A.M.R.; Rabbitts, P.H.; Boullier, B.; Rabbitts, T.H.

    1987-01-01

    T-cell tumors are characterized by inversions or translocations of chromosome 14. The breakpoints of these karyotypic abnormalities occur in chromosome bands 14q11 and 14q32 - the same bands in which the T-cell receptor (TCR) α-chain and immunoglobulin heavy chain genes have been mapped, respectively. Patients with ataxia-telangiectasia are particularly prone to development of T-cell chronic lymphocytic leukemia with such chromosomal abnormalities. The authors describe DNA rearrangements of the TCR α-chain gene in an ataxia-telangiectasia-associated leukemia containing both a normal and an inverted chromosome 14. The normal chromosome 14 has undergone a productive join of TCR α-chain variable (V/sub α/) and joining (J/sub α/) gene segments. The other allele of the TCR α-chain gene features a DNA rearrangement, about 50 kilobases from the TCR α-chain constant (C/sub α/) gene, that represents the breakpoint of the chromosome 14 inversion; this breakpoint is comprised of a TCR J/sub α/) segment (from 14q11) fused to sequences derived from 14q32 but on the centromeric side of C/sub μ/. These results imply that 14q32 sequences located at an undetermined distance downstream of immunoglobulin C/sub μ/ locus can contribute to the development of T-cell tumors

  12. Vaccination against lymphocytic choriomeningitis virus infection in MHC class II-deficient mice

    DEFF Research Database (Denmark)

    Holst, Peter Johannes; Christensen, Jan Pravsgaard; Thomsen, Allan Randrup

    2011-01-01

    response could be elicited in MHC class II-deficient mice by vaccination with adenovirus encoding lymphocytic choriomeningitis virus (LCMV) glycoprotein tethered to MHC class II-associated invariant chain. Moreover, the response induced conferred significant cytolytic CD8(+) T cell-mediated protection...... against challenge with a high dose of the invasive clone 13 strain of LCMV. In contrast, vaccination with adenovirus encoding unlinked LCMV glycoprotein induced weak virus control in the absence of CD4(+) T cells, and mice may die of increased immunopathology associated with incomplete protection. Acute...... mortality was not observed in any vaccinated mice following infection with the less-invasive Traub strain. However, LCMV Traub infection caused accelerated late mortality in unvaccinated MHC class II-deficient mice; in this case, we observed a strong trend toward delayed mortality in vaccinated mice...

  13. Cloning of cDNAs coding for the heavy chain region and connecting region of human factor V, a blood coagulation factor with four types of internal repeats

    International Nuclear Information System (INIS)

    Kane, W.H.; Ichinose, A.; Hagen, F.S.; Davie, E.W.

    1987-01-01

    Human factor V is a high molecular weight plasma glycoprotein that participates as a cofactor in the conversion of prothrombin to thrombin by factor X/sub a/. Prior to its participation in the coagulation cascade, factor V is converted to factor V/sub a/ by thrombin generating a heavy chain and a light chain, and these two chains are held together by calcium ions. A connecting region originally located between the heavy and light chains is liberated during the activation reaction. In a previous study, a cDNA of 2970 nucleotides that codes for the carboxyl-terminal 938 amino acids of factor V was isolated and characterized from a Hep G2 cDNA library. This cDNA has been used to obtain additional clones from Hep G2 and human liver cDNA libraries. Furthermore, a Hep G2 cDNA library prepared with an oligonucleotide from the 5' end of these cDNAs was screened to obtain overlapping cDNA clones that code for the amino-terminal region of the molecule. The composite sequence of these clones spans 6911 nucleotides and is consistent with the size of the factor V message present in Hep G2 cells (approximately 7 kilobases). The cDNA codes for a leader sequence of 28 amino acids and a mature protein of 2196 amino acids. The amino acid sequence predicted from the cDNA was in complete agreement with 139 amino acid residues that were identified by Edman degradation of cyanogen bromide peptides isolated from the heavy chain region and connecting region of plasma factor V. The domain structure of human factor V is similar to that previously reported for human coagulation factor VIII. Two types of tandem repeats (17 and 9 amino acids) have also been identified in the connecting region of factor V. The present data indicate that the amino acid sequence in the heavy and light chain regions of factor V is ∼ 40% identical with the corresponding regions of factor VIII

  14. Molecular cloning of complementary DNAs encoding the heavy chain of the human 4F2 cell-surface antigen: a type II membrane glycoprotein involved in normal and neoplastic cell growth

    International Nuclear Information System (INIS)

    Quackenbush, E.; Clabby, M.; Gottesdiener, K.M.; Barbosa, J.; Jones, N.H.; Strominger, J.L.; Speck, S.; Leiden, J.M.

    1987-01-01

    Complementary DNA (cDNA) clones encoding the heavy chain of the heterodimeric human membrane glycoprotein 4F2 have been isolated by immunoscreening of a λgt11 expression library. The identity of these clones has been confirmed by hybridization to RNA and DNA prepared from mouse L-cell transfectants, which were produced by whole cell gene transfer and selected for cell-surface expression of the human 4F2 heavy chain. DNA sequence analysis suggest that the 4F2 heavy-chain cDNAs encode an approximately 526-amino acid type II membrane glycoprotein, which is composed of a large C-terminal extracellular domain, a single potential transmembrane region, and a 50-81 amino acid N-terminal intracytoplasmic domain. Southern blotting experiments have shown that the 4F2 heavy-chain cDNAs are derived from a single-copy gene that has been highly conserved during mammalian evolution

  15. Structural properties of MHC class II ligands, implications for the prediction of MHC class II epitopes.

    Directory of Open Access Journals (Sweden)

    Kasper Winther Jørgensen

    2010-12-01

    Full Text Available Major Histocompatibility class II (MHC-II molecules sample peptides from the extracellular space allowing the immune system to detect the presence of foreign microbes from this compartment. Prediction of MHC class II ligands is complicated by the open binding cleft of the MHC class II molecule, allowing binding of peptides extending out of the binding groove. Furthermore, only a few HLA-DR alleles have been characterized with a sufficient number of peptides (100-200 peptides per allele to derive accurate description of their binding motif. Little work has been performed characterizing structural properties of MHC class II ligands. Here, we perform one such large-scale analysis. A large set of SYFPEITHI MHC class II ligands covering more than 20 different HLA-DR molecules was analyzed in terms of their secondary structure and surface exposure characteristics in the context of the native structure of the corresponding source protein. We demonstrated that MHC class II ligands are significantly more exposed and have significantly more coil content than other peptides in the same protein with similar predicted binding affinity. We next exploited this observation to derive an improved prediction method for MHC class II ligands by integrating prediction of MHC- peptide binding with prediction of surface exposure and protein secondary structure. This combined prediction method was shown to significantly outperform the state-of-the-art MHC class II peptide binding prediction method when used to identify MHC class II ligands. We also tried to integrate N- and O-glycosylation in our prediction methods but this additional information was found not to improve prediction performance. In summary, these findings strongly suggest that local structural properties influence antigen processing and/or the accessibility of peptides to the MHC class II molecule.

  16. A highly tilted binding mode by a self-reactive T cell receptor results in altered engagement of peptide and MHC

    Energy Technology Data Exchange (ETDEWEB)

    Sethi, D.K.; Heroux, A.; Schubert, D. A.; Anders, A.-K.; Bonsor, D. A.; Thomas, C. P.; Sundberg, E. J.; Pyrdol, J.; Wucherpfennig, K. W.

    2011-01-17

    Self-reactive T cells that escape elimination in the thymus can cause autoimmune pathology, and it is therefore important to understand the structural mechanisms of self-antigen recognition. We report the crystal structure of a T cell receptor (TCR) from a patient with relapsing-remitting multiple sclerosis that engages its self-peptide-major histocompatibility complex (pMHC) ligand in an unusual manner. The TCR is bound in a highly tilted orientation that prevents interaction of the TCR-{alpha} chain with the MHC class II {beta} chain helix. In this structure, only a single germline-encoded TCR loop engages the MHC protein, whereas in most other TCR-pMHC structures all four germline-encoded TCR loops bind to the MHC helices. The tilted binding mode also prevents peptide contacts by the short complementarity-determining region (CDR) 3{beta} loop, and interactions that contribute to peptide side chain specificity are focused on the CDR3{alpha} loop. This structure is the first example in which only a single germline-encoded TCR loop contacts the MHC helices. Furthermore, the reduced interaction surface with the peptide may facilitate TCR cross-reactivity. The structural alterations in the trimolecular complex are distinct from previously characterized self-reactive TCRs, indicating that there are multiple unusual ways for self-reactive TCRs to bind their pMHC ligand.

  17. A Highly Tilted Binding Mode by a Self-Reactive T Cell Receptor Results in Altered Engagement of Peptide and MHC

    Energy Technology Data Exchange (ETDEWEB)

    D Sethi; D Schubert; A Anders; A Heroux; D Bonsor; C Thomas; E Sundberg; J Pyrdol; K Wucherpfennig

    2011-12-31

    Self-reactive T cells that escape elimination in the thymus can cause autoimmune pathology, and it is therefore important to understand the structural mechanisms of self-antigen recognition. We report the crystal structure of a T cell receptor (TCR) from a patient with relapsing-remitting multiple sclerosis that engages its self-peptide-major histocompatibility complex (pMHC) ligand in an unusual manner. The TCR is bound in a highly tilted orientation that prevents interaction of the TCR-{alpha} chain with the MHC class II {beta} chain helix. In this structure, only a single germline-encoded TCR loop engages the MHC protein, whereas in most other TCR-pMHC structures all four germline-encoded TCR loops bind to the MHC helices. The tilted binding mode also prevents peptide contacts by the short complementarity-determining region (CDR) 3{beta} loop, and interactions that contribute to peptide side chain specificity are focused on the CDR3{alpha} loop. This structure is the first example in which only a single germline-encoded TCR loop contacts the MHC helices. Furthermore, the reduced interaction surface with the peptide may facilitate TCR cross-reactivity. The structural alterations in the trimolecular complex are distinct from previously characterized self-reactive TCRs, indicating that there are multiple unusual ways for self-reactive TCRs to bind their pMHC ligand.

  18. Responses of Myosin Heavy Chain Phenotypes and Gene Expressions in Neck Muscle to Micro- an Hyper-Gravity in Mice

    Science.gov (United States)

    Ohira, Tomotaka; Ohira, Takashi; Kawano, F.; Shibaguchi, T.; Okabe, H.; Ohno, Y.; Nakai, N.; Ochiai, T.; Goto, K.; Ohira, Y.

    2013-02-01

    Neck muscles are known to play important roles in the maintenance of head posture against gravity. However, it is not known how the properties of neck muscle are influenced by gravity. Therefore, the current study was performed to investigate the responses of neck muscle (rhomboideus capitis) in mice to inhibition of gravity and/or increase to 2-G for 3 months to test the hypothesis that the properties of neck muscles are regulated in response to the level of mechanical load applied by the gravitational load. Three male wild type C57BL/10J mice (8 weeks old) were launched by space shuttle Discovery (STS-128) and housed in Japanese Experimental Module “KIBO” on the International Space Station in mouse drawer system (MDS) project, which was organized by Italian Space Agency. Only 1 mouse returned to the Earth alive after 3 months by space shuttle Atlantis (STS-129). Neck muscles were sampled from both sides within 3 hours after landing. Cage and laboratory control experiments were also performed on the ground. Further, 3-month ground-based control experiments were performed with 6 groups, i.e. pre-experiment, 3-month hindlimb suspension, 2-G exposure by using animal centrifuge, and vivarium control (n=5 each group). Five mice were allowed to recover from hindlimb suspension (including 5 cage control) for 3 months in the cage. Neck muscles were sampled bilaterally before and after 3-month suspension and 2-G exposure, and at the end of 3-month ambulation recovery. Spaceflight-associated shift of myosin heavy chain phenotype from type I to II and atrophy of type I fibers were observed. In response to spaceflight, 17 genes were up-regulated and 13 genes were down-regulated vs. those in the laboratory control. Expression of 6 genes were up-regulated and that of 88 genes were down-regulated by 3-month exposure to 2-G vs. the age-matched cage control. In response to chronic hindlimb suspension, 4 and 20 genes were up- or down-regulated. Further, 98 genes responded

  19. The MHC motif viewer: a visualization tool for MHC binding motifs

    DEFF Research Database (Denmark)

    Rapin, Nicolas; Hoof, Ilka; Lund, Ole

    2010-01-01

    is hampered by the lack of tools for browsing and comparing specificity of these molecules. We have developed a Web server, MHC Motif Viewer, which allows the display of the binding motif for MHC class I proteins for human, chimpanzee, rhesus monkey, mouse, and swine, as well as HLA-DR protein sequences...

  20. Combined Cytolytic Effects of a Vaccinia Virus Encoding a Single Chain Trimer of MHC-I with a Tax-Epitope and Tax-Specific CTLs on HTLV-I-Infected Cells in a Rat Model

    Directory of Open Access Journals (Sweden)

    Takashi Ohashi

    2014-01-01

    Full Text Available Adult T cell leukemia (ATL is a malignant lymphoproliferative disease caused by human T cell leukemia virus type I (HTLV-I. To develop an effective therapy against the disease, we have examined the oncolytic ability of an attenuated vaccinia virus (VV, LC16m8Δ (m8Δ, and an HTLV-I Tax-specific cytotoxic T lymphocyte (CTL line, 4O1/C8, against an HTLV-I-infected rat T cell line, FPM1. Our results demonstrated that m8Δ was able to replicate in and lyse tumorigenic FPM1 cells but was incompetent to injure 4O1/C8 cells, suggesting the preferential cytolytic activity toward tumor cells. To further enhance the cytolysis of HTLV-I-infected cells, we modified m8Δ and obtained m8Δ/RT1AlSCTax180L, which can express a single chain trimer (SCT of rat major histocompatibility complex class I with a Tax-epitope. Combined treatment with m8Δ/RT1AlSCTax180L and 4O1/C8 increased the cytolysis of FPM1V.EFGFP/8R cells, a CTL-resistant subclone of FPM1, compared with that using 4O1/C8 and m8Δ presenting an unrelated peptide, suggesting that the activation of 4O1/C8 by m8Δ/RT1AlSCTax180L further enhanced the killing of the tumorigenic HTLV-I-infected cells. Our results indicate that combined therapy of oncolytic VVs with SCTs and HTLV-I-specific CTLs may be effective for eradication of HTLV-I-infected cells, which evade from CTL lysis and potentially develop ATL.

  1. A shark antibody heavy chain encoded by a nonsomatically rearranged VDJ is preferentially expressed in early development and is convergent with mammalian IgG.

    Science.gov (United States)

    Rumfelt, L L; Avila, D; Diaz, M; Bartl, S; McKinney, E C; Flajnik, M F

    2001-02-13

    In most vertebrate embryos and neonates studied to date unique antigen receptors (antibodies and T cell receptors) are expressed that possess a limited immune repertoire. We have isolated a subclass of IgM, IgM(1gj), from the nurse shark Ginglymostoma cirratum that is preferentially expressed in neonates. The variable (V) region gene encoding the heavy (H) chain underwent V-D-J rearrangement in germ cells ("germline-joined"). Such H chain V genes were discovered over 10 years ago in sharks but until now were not shown to be expressed at appreciable levels; we find expression of H(1gj) in primary and secondary lymphoid tissues early in life, but in adults only in primary lymphoid tissue, which is identified in this work as the epigonal organ. H(1gj) chain associates covalently with light (L) chains and is most similar in sequence to IgM H chains, but like mammalian IgG has three rather than the four IgM constant domains; deletion of the ancestral IgM C2 domain thus defines both IgG and IgM(1gj). Because sharks are the members of the oldest vertebrate class known to possess antibodies, unique or specialized antibodies expressed early in ontogeny in sharks and other vertebrates were likely present at the inception of the adaptive immune system.

  2. Rejection of class I MHC-deficient haemopoietic cells by irradiated MHC-matched mice

    International Nuclear Information System (INIS)

    Bix, M.; Nanshih Liao; Raulet, D.; Zijlstra, M.; Loring, J.; Jaenisch, R.

    1991-01-01

    Irradiated MHC-heterozygous mice often reject bone marrow cells transplanted from one of the homozygous parental strains, a phenomenon ('hybrid resistance') that appears to violate the laws of transplantation. Rejection of parental and allogeneic marrow cells also differs from conventional T cell-mediated rejection mechanisms as it is effected by NK1.1 + cells. To account for the unusual specificity of bone marrow rejection, it has been proposed that NK1.1 + cells destroy marrow cells that fail to express the full complement of self MHC class I (MHC-I) molecules. We show here that NK1.1 + cells in normal mice reject haemopoietic transplants from mice that are deficient for normal cell-surface MHC-I expression because of a targeted mutation in the β 2 -microglobulin gene. These findings demonstrate that deficient expression of MHC-I molecules renders marrow cells susceptible to rejection. (author)

  3. The SysteMHC Atlas project.

    Science.gov (United States)

    Shao, Wenguang; Pedrioli, Patrick G A; Wolski, Witold; Scurtescu, Cristian; Schmid, Emanuel; Vizcaíno, Juan A; Courcelles, Mathieu; Schuster, Heiko; Kowalewski, Daniel; Marino, Fabio; Arlehamn, Cecilia S L; Vaughan, Kerrie; Peters, Bjoern; Sette, Alessandro; Ottenhoff, Tom H M; Meijgaarden, Krista E; Nieuwenhuizen, Natalie; Kaufmann, Stefan H E; Schlapbach, Ralph; Castle, John C; Nesvizhskii, Alexey I; Nielsen, Morten; Deutsch, Eric W; Campbell, David S; Moritz, Robert L; Zubarev, Roman A; Ytterberg, Anders Jimmy; Purcell, Anthony W; Marcilla, Miguel; Paradela, Alberto; Wang, Qi; Costello, Catherine E; Ternette, Nicola; van Veelen, Peter A; van Els, Cécile A C M; Heck, Albert J R; de Souza, Gustavo A; Sollid, Ludvig M; Admon, Arie; Stevanovic, Stefan; Rammensee, Hans-Georg; Thibault, Pierre; Perreault, Claude; Bassani-Sternberg, Michal; Aebersold, Ruedi; Caron, Etienne

    2018-01-04

    Mass spectrometry (MS)-based immunopeptidomics investigates the repertoire of peptides presented at the cell surface by major histocompatibility complex (MHC) molecules. The broad clinical relevance of MHC-associated peptides, e.g. in precision medicine, provides a strong rationale for the large-scale generation of immunopeptidomic datasets and recent developments in MS-based peptide analysis technologies now support the generation of the required data. Importantly, the availability of diverse immunopeptidomic datasets has resulted in an increasing need to standardize, store and exchange this type of data to enable better collaborations among researchers, to advance the field more efficiently and to establish quality measures required for the meaningful comparison of datasets. Here we present the SysteMHC Atlas (https://systemhcatlas.org), a public database that aims at collecting, organizing, sharing, visualizing and exploring immunopeptidomic data generated by MS. The Atlas includes raw mass spectrometer output files collected from several laboratories around the globe, a catalog of context-specific datasets of MHC class I and class II peptides, standardized MHC allele-specific peptide spectral libraries consisting of consensus spectra calculated from repeat measurements of the same peptide sequence, and links to other proteomics and immunology databases. The SysteMHC Atlas project was created and will be further expanded using a uniform and open computational pipeline that controls the quality of peptide identifications and peptide annotations. Thus, the SysteMHC Atlas disseminates quality controlled immunopeptidomic information to the public domain and serves as a community resource toward the generation of a high-quality comprehensive map of the human immunopeptidome and the support of consistent measurement of immunopeptidomic sample cohorts. © The Author(s) 2017. Published by Oxford University Press on behalf of Nucleic Acids Research.

  4. NLRC5: a newly discovered MHC class I transactivator (CITA)

    OpenAIRE

    Meissner, Torsten B.; Li, Amy; Kobayashi, Koichi S.

    2011-01-01

    Major histocompatibility complex (MHC) class I and class II are crucial for the function of the human adaptive immune system. An NLR protein, CIITA (MHC class II transactivator), is a master regulator of MHC class II gene expression as well as of some of the genes involved in MHC class II antigen presentation. It has recently been discovered that another member of the NLR protein family, NLRC5, transcriptionally activates MHC class I genes, and thus acts as “CITA” (MHC class I transactivator)...

  5. Epigenetic mechanisms regulate MHC and antigen processing molecules in human embryonic and induced pluripotent stem cells.

    Directory of Open Access Journals (Sweden)

    Beatriz Suárez-Alvarez

    2010-04-01

    Full Text Available Human embryonic stem cells (hESCs are an attractive resource for new therapeutic approaches that involve tissue regeneration. hESCs have exhibited low immunogenicity due to low levels of Mayor Histocompatibility Complex (MHC class-I and absence of MHC class-II expression. Nevertheless, the mechanisms regulating MHC expression in hESCs had not been explored.We analyzed the expression levels of classical and non-classical MHC class-I, MHC class-II molecules, antigen-processing machinery (APM components and NKG2D ligands (NKG2D-L in hESCs, induced pluripotent stem cells (iPSCs and NTera2 (NT2 teratocarcinoma cell line. Epigenetic mechanisms involved in the regulation of these genes were investigated by bisulfite sequencing and chromatin immunoprecipitation (ChIP assays. We showed that low levels of MHC class-I molecules were associated with absent or reduced expression of the transporter associated with antigen processing 1 (TAP-1 and tapasin (TPN components in hESCs and iPSCs, which are involved in the transport and load of peptides. Furthermore, lack of beta2-microglobulin (beta2m light chain in these cells limited the expression of MHC class I trimeric molecule on the cell surface. NKG2D ligands (MICA, MICB were observed in all pluripotent stem cells lines. Epigenetic analysis showed that H3K9me3 repressed the TPN gene in undifferentiated cells whilst HLA-B and beta2m acquired the H3K4me3 modification during the differentiation to embryoid bodies (EBs. Absence of HLA-DR and HLA-G expression was regulated by DNA methylation.Our data provide fundamental evidence for the epigenetic control of MHC in hESCs and iPSCs. Reduced MHC class I and class II expression in hESCs and iPSCs can limit their recognition by the immune response against these cells. The knowledge of these mechanisms will further allow the development of strategies to induce tolerance and improve stem cell allograft acceptance.

  6. Epigenetic Mechanisms Regulate MHC and Antigen Processing Molecules in Human Embryonic and Induced Pluripotent Stem Cells

    Science.gov (United States)

    Suárez-Álvarez, Beatriz; Rodriguez, Ramón M.; Calvanese, Vincenzo; Blanco-Gelaz, Miguel A.; Suhr, Steve T.; Ortega, Francisco; Otero, Jesus; Cibelli, Jose B.; Moore, Harry; Fraga, Mario F.; López-Larrea, Carlos

    2010-01-01

    Background Human embryonic stem cells (hESCs) are an attractive resource for new therapeutic approaches that involve tissue regeneration. hESCs have exhibited low immunogenicity due to low levels of Mayor Histocompatibility Complex (MHC) class-I and absence of MHC class-II expression. Nevertheless, the mechanisms regulating MHC expression in hESCs had not been explored. Methodology/Principal Findings We analyzed the expression levels of classical and non-classical MHC class-I, MHC class-II molecules, antigen-processing machinery (APM) components and NKG2D ligands (NKG2D-L) in hESCs, induced pluripotent stem cells (iPSCs) and NTera2 (NT2) teratocarcinoma cell line. Epigenetic mechanisms involved in the regulation of these genes were investigated by bisulfite sequencing and chromatin immunoprecipitation (ChIP) assays. We showed that low levels of MHC class-I molecules were associated with absent or reduced expression of the transporter associated with antigen processing 1 (TAP-1) and tapasin (TPN) components in hESCs and iPSCs, which are involved in the transport and load of peptides. Furthermore, lack of β2-microglobulin (β2m) light chain in these cells limited the expression of MHC class I trimeric molecule on the cell surface. NKG2D ligands (MICA, MICB) were observed in all pluripotent stem cells lines. Epigenetic analysis showed that H3K9me3 repressed the TPN gene in undifferentiated cells whilst HLA-B and β2m acquired the H3K4me3 modification during the differentiation to embryoid bodies (EBs). Absence of HLA-DR and HLA-G expression was regulated by DNA methylation. Conclusions/Significance Our data provide fundamental evidence for the epigenetic control of MHC in hESCs and iPSCs. Reduced MHC class I and class II expression in hESCs and iPSCs can limit their recognition by the immune response against these cells. The knowledge of these mechanisms will further allow the development of strategies to induce tolerance and improve stem cell allograft acceptance

  7. Myosin heavy chain-like localizes at cell contact sites during Drosophila myoblast fusion and interacts in vitro with Rolling pebbles 7

    Energy Technology Data Exchange (ETDEWEB)

    Bonn, Bettina R.; Rudolf, Anja; Hornbruch-Freitag, Christina; Daum, Gabor; Kuckwa, Jessica; Kastl, Lena; Buttgereit, Detlev [Developmental Biology, Department of Biology, Philipps-Universität Marburg, Karl-von-Frisch-Strasse 8, 35037 Marburg (Germany); Renkawitz-Pohl, Renate, E-mail: renkawit@biologie.uni-marburg.de [Developmental Biology, Department of Biology, Philipps-Universität Marburg, Karl-von-Frisch-Strasse 8, 35037 Marburg (Germany)

    2013-02-15

    Besides representing the sarcomeric thick filaments, myosins are involved in many cellular transport and motility processes. Myosin heavy chains are grouped into 18 classes. Here we show that in Drosophila, the unconventional group XVIII myosin heavy chain-like (Mhcl) is transcribed in the mesoderm of embryos, most prominently in founder cells (FCs). An ectopically expressed GFP-tagged Mhcl localizes in the growing muscle at cell–cell contacts towards the attached fusion competent myoblast (FCM). We further show that Mhcl interacts in vitro with the essential fusion protein Rolling pebbles 7 (Rols7), which is part of a protein complex established at cell contact sites (Fusion-restricted Myogenic-Adhesive Structure or FuRMAS). Here, branched F-actin is likely needed to widen the fusion pore and to integrate the myoblast into the growing muscle. We show that the localization of Mhcl is dependent on the presence of Rols7, and we postulate that Mhcl acts at the FuRMAS as an actin motor protein. We further show that Mhcl deficient embryos develop a wild-type musculature. We thus propose that Mhcl functions redundantly to other myosin heavy chains in myoblasts. Lastly, we found that the protein is detectable adjacent to the sarcomeric Z-discs, suggesting an additional function in mature muscles. - Highlights: ► The class XVIII myosin encoding gene Mhcl is transcribed in the mesoderm. ► Mhcl localization at contact sites of fusing myoblasts depends on Rols7. ► Mhcl interacts in vitro with Rols7 which is essential for myogenesis. ► Functional redundancy with other myosins is likely as mutants show no muscle defects. ► Mhcl localizes adjacent to Z-discs of sarcomeres and might support muscle integrity.

  8. Myosin heavy chain-like localizes at cell contact sites during Drosophila myoblast fusion and interacts in vitro with Rolling pebbles 7

    International Nuclear Information System (INIS)

    Bonn, Bettina R.; Rudolf, Anja; Hornbruch-Freitag, Christina; Daum, Gabor; Kuckwa, Jessica; Kastl, Lena; Buttgereit, Detlev; Renkawitz-Pohl, Renate

    2013-01-01

    Besides representing the sarcomeric thick filaments, myosins are involved in many cellular transport and motility processes. Myosin heavy chains are grouped into 18 classes. Here we show that in Drosophila, the unconventional group XVIII myosin heavy chain-like (Mhcl) is transcribed in the mesoderm of embryos, most prominently in founder cells (FCs). An ectopically expressed GFP-tagged Mhcl localizes in the growing muscle at cell–cell contacts towards the attached fusion competent myoblast (FCM). We further show that Mhcl interacts in vitro with the essential fusion protein Rolling pebbles 7 (Rols7), which is part of a protein complex established at cell contact sites (Fusion-restricted Myogenic-Adhesive Structure or FuRMAS). Here, branched F-actin is likely needed to widen the fusion pore and to integrate the myoblast into the growing muscle. We show that the localization of Mhcl is dependent on the presence of Rols7, and we postulate that Mhcl acts at the FuRMAS as an actin motor protein. We further show that Mhcl deficient embryos develop a wild-type musculature. We thus propose that Mhcl functions redundantly to other myosin heavy chains in myoblasts. Lastly, we found that the protein is detectable adjacent to the sarcomeric Z-discs, suggesting an additional function in mature muscles. - Highlights: ► The class XVIII myosin encoding gene Mhcl is transcribed in the mesoderm. ► Mhcl localization at contact sites of fusing myoblasts depends on Rols7. ► Mhcl interacts in vitro with Rols7 which is essential for myogenesis. ► Functional redundancy with other myosins is likely as mutants show no muscle defects. ► Mhcl localizes adjacent to Z-discs of sarcomeres and might support muscle integrity

  9. Designing Optimal LNG Station Network for U.S. Heavy-Duty Freight Trucks using Temporally and Spatially Explicit Supply Chain Optimization

    Science.gov (United States)

    Lee, Allen

    The recent natural gas boom has opened much discussion about the potential of natural gas and specifically Liquefied Natural Gas (LNG) in the United States transportation sector. The switch from diesel to natural gas vehicles would reduce foreign dependence on oil, spur domestic economic growth, and potentially reduce greenhouse gas emissions. LNG provides the most potential for the medium to heavy-duty vehicle market partially due to unstable oil prices and stagnant natural gas prices. As long as the abundance of unconventional gas in the United States remains cheap, fuel switching to natural gas could provide significant cost savings for long haul freight industry. Amid a growing LNG station network and ever increasing demand for freight movement, LNG heavy-duty truck sales are less than anticipated and the industry as a whole is less economic than expected. In spite of much existing and mature natural gas infrastructure, the supply chain for LNG is different and requires explicit and careful planning. This thesis proposes research to explore the claim that the largest obstacle to widespread LNG market penetration is sub-optimal infrastructure planning. No other study we are aware of has explicitly explored the LNG transportation fuel supply chain for heavy-duty freight trucks. This thesis presents a novel methodology that links a network infrastructure optimization model (represents supply side) with a vehicle stock and economic payback model (represents demand side). The model characterizes both a temporal and spatial optimization model of future LNG transportation fuel supply chains in the United States. The principal research goal is to assess the economic feasibility of the current LNG transportation fuel industry and to determine an optimal pathway to achieve ubiquitous commercialization of LNG vehicles in the heavy-duty transport sector. The results indicate that LNG is not economic as a heavy-duty truck fuel until 2030 under current market conditions

  10. Heavy-chain isotype patterns of human antibody-secreting cells induced by Haemophilus influenzae type b conjugate vaccines in relation to age and preimmunity

    DEFF Research Database (Denmark)

    Barington, T; Juul, Lars; Gyhrs, A

    1994-01-01

    The influence of preexisting immunity on the heavy-chain isotypes of circulating antibody-secreting cells (AbSC) induced by vaccination with Haemophilus influenzae type b (Hib) capsular polysaccharide (HibCP) coupled to tetanus toxoid (TT) or diphtheria toxoid (DT) and by vaccination with TT or D...... of natural HibCP antibodies (r = 0.59; P = 0.00002). A possible role of natural exposure for Hib or cross-reactive bacteria on the mucosal surfaces in the shaping of the isotype response to HibCP conjugate vaccines is discussed....

  11. Myosin heavy chain isoform expression in adult and juvenile mini-muscle mice bred for high-voluntary wheel running.

    Science.gov (United States)

    Talmadge, Robert J; Acosta, Wendy; Garland, Theodore

    2014-11-01

    The myosin heavy chain (MyHC) isoform composition of locomotor and non-locomotor muscles of mini-muscle mice were assessed at the protein and mRNA levels in both adult and juvenile (21 day old) mice. Mini-muscle mice are one outcome of a replicated artificial selection experiment in which four lines of mice were bred for high voluntary wheel running (HR lines). Two of the lines responded with an increase in frequency of a single nucleotide polymorphism in an intron in the MyHC-2b gene (myh4) that when homozygous causes a dramatic reduction in triceps surae mass. We found that both locomotor and non-locomotor muscles of adult mini-muscle mice displayed robust reductions, but not elimination, of the MyHC-2b isoform at both the protein and mRNA levels, with commensurate increases in MyHC-2x and sometimes MyHC-2a, as compared with either a line of HR mice that does not display the mini-muscle phenotype or inbred C57Bl6 mice. Immunohistochemical analyses revealed that locomotor muscles of mini-muscle mice contain fibers that express the MyHC-2b isoform, which migrates normally in SDS-PAGE gels. However, these MyHC-2b positive fibers are generally smaller than the surrounding fibers and smaller than the MyHC-2b positive fibers of non-mini-muscle mice, resulting in characteristically fast muscles that lack a substantial MyHC-2b positive (superficial) region. In contrast, the masseter, a non-locomotor muscle of mini-muscle mice contained MyHC-2b positive fibers that stained more lightly for MyHC-2b, but appeared normal in size and distribution. In adults, many of the MyHC-2b positive fibers in the mini-muscle mice also display central nuclei. Only a small proportion of small MyHC-2b fibers in mini-muscle mice stained positive for the neural cell adhesion molecule, suggesting that anatomical innervation was not compromised. In addition, weanling (21 day old), but not 5 day old mice, displayed alterations in MyHC isoform content at both the protein and mRNA levels, including

  12. Generation of murine tumor cell lines deficient in MHC molecule surface expression using the CRISPR/Cas9 system.

    Directory of Open Access Journals (Sweden)

    Krishna Das

    Full Text Available In this study, the CRISPR/Cas9 technology was used to establish murine tumor cell lines, devoid of MHC I or MHC II surface expression, respectively. The melanoma cell line B16F10 and the murine breast cancer cell line EO-771, the latter stably expressing the tumor antigen NY-BR-1 (EO-NY, were transfected with an expression plasmid encoding a β2m-specific single guide (sgRNA and Cas9. The resulting MHC I negative cells were sorted by flow cytometry to obtain single cell clones, and loss of susceptibility of peptide pulsed MHC I negative clones to peptide-specific CTL recognition was determined by IFNγ ELISpot assay. The β2m knockout (KO clones did not give rise to tumors in syngeneic mice (C57BL/6N, unless NK cells were depleted, suggesting that outgrowth of the β2m KO cell lines was controlled by NK cells. Using sgRNAs targeting the β-chain encoding locus of the IAb molecule we also generated several B16F10 MHC II KO clones. Peptide loaded B16F10 MHC II KO cells were insusceptible to recognition by OT-II cells and tumor growth was unaltered compared to parental B16F10 cells. Thus, in our hands the CRISPR/Cas9 system has proven to be an efficient straight forward strategy for the generation of MHC knockout cell lines. Such cell lines could serve as parental cells for co-transfection of compatible HLA alleles together with human tumor antigens of interest, thereby facilitating the generation of HLA matched transplantable tumor models, e.g. in HLAtg mouse strains of the newer generation, lacking cell surface expression of endogenous H2 molecules. In addition, our tumor cell lines established might offer a useful tool to investigate tumor reactive T cell responses that function independently from MHC molecule surface expression by the tumor.

  13. Study of heavy metals in the grass-milk product chain by means of neutron activation and atomic absorption

    Energy Technology Data Exchange (ETDEWEB)

    Bruant, C; Bruant, J P; Neuburger, M; Vassal, L; Disant, C; Bittel, R; Fourcy, A

    1974-12-31

    with the heavy metals Hg, Cu, Zn, Pb, and Cd is studied. The first three metals were determined by neutron activation and tae last two by atomic absorption spectrophotometry. The chemical rature of these metals and their biological effect leads to different results from those obtained for tae principal fission products. As a rule the heavy metal concentrations at harvest are much lower than taat of the foods ingested by lactating cows. The cow plays the role of filter. If the concentration of these elements is considered in mu g/g of fresh material there is a reconcentration of these heavy metals in cream and cheese, probably cornected with their physico-chemical affinity for proteins. (JSR)

  14. IMGT unique numbering for MHC groove G-DOMAIN and MHC superfamily (MhcSF) G-LIKE-DOMAIN

    DEFF Research Database (Denmark)

    Lefranc, Marie-Paule; Duprat, E.; Kaas, Quentin

    2005-01-01

    IMGT, the international ImMunoGeneTics information system® (http://imgt.cines.fr) provides a common access to expertly annotated data on the genome, proteome, genetics and structure of immunoglobulins (IG), T cell receptors (TR), major histocompatibility complex (MHC), and related proteins...

  15. A hybrid approach for predicting promiscuous MHC class I restricted ...

    Indian Academy of Sciences (India)

    Prakash

    2006-09-15

    Sep 15, 2006 ... with existing MHC binder prediction methods for alleles studied by both ... in locating the promiscuous MHC binding regions from antigen sequence. ... Artificial neural network; MHC class I alleles; promiscuous binders; ... this problem by developing methods for prediction for ... In case equal number of.

  16. Brucella abortus down-regulates MHC class II by the IL-6-dependent inhibition of CIITA through the downmodulation of IFN regulatory factor-1 (IRF-1).

    Science.gov (United States)

    Velásquez, Lis N; Milillo, M Ayelén; Delpino, M Victoria; Trotta, Aldana; Fernández, Pablo; Pozner, Roberto G; Lang, Roland; Balboa, Luciana; Giambartolomei, Guillermo H; Barrionuevo, Paula

    2017-03-01

    Brucella abortus is an intracellular pathogen capable of surviving inside of macrophages. The success of B. abortus as a chronic pathogen relies on its ability to orchestrate different strategies to evade the adaptive CD4 + T cell responses that it elicits. Previously, we demonstrated that B. abortus inhibits the IFN-γ-induced surface expression of MHC class II (MHC-II) molecules on human monocytes, and this phenomenon correlated with a reduction in antigen presentation. However, the molecular mechanisms, whereby B. abortus is able to down-regulate the expression of MHC-II, remained to be elucidated. In this study, we demonstrated that B. abortus infection inhibits the IFN-γ-induced transcription of MHC-II, transactivator (CIITA) and MHC-II genes. Accordingly, we observed that the synthesis of MHC-II proteins was also diminished. B. abortus was not only able to reduce the expression of mature MHC-II, but it also inhibited the expression of invariant chain (Ii)-associated immature MHC-II molecules. Outer membrane protein 19 (Omp19), a prototypical B. abortus lipoprotein, diminished the expression of MHC-II and CIITA transcripts to the same extent as B. abortus infection. IL-6 contributes to these down-regulatory phenomena. In addition, B. abortus and its lipoproteins, through IL-6 secretion, induced the transcription of the negative regulators of IFN-γ signaling, suppressor of cytokine signaling (SOCS)-1 and -3, without interfering with STAT1 activation. Yet, B. abortus lipoproteins via IL-6 inhibit the expression of IFN regulatory factor 1 (IRF-1), a critical regulatory transcription factor for CIITA induction. Overall, these results indicate that B. abortus inhibits the expression of MHC-II molecules at very early points in their synthesis and in this way, may prevent recognition by T cells establishing a chronic infection. © Society for Leukocyte Biology.

  17. MHC classⅠ gene in two duck lines

    Indian Academy of Sciences (India)

    Navya

    Weishan Ma duck (WS) is the eugenic endemic breed, one of the four famous ducks in China, as well Cherry Valley duck (CV) is the largest number of breeding variety. WS is egg strain and CV is meat type. The two duck lines mainly support the. Chinese waterfowl industry. In this study, MHC class Ⅰ genes of WS and CV ...

  18. MHC Region and Its Related Disease Study

    DEFF Research Database (Denmark)

    Cao, Hongzhi

    The major histocompatibility complex (MHC) is one of the most gene dense regions in the human genome and many disorders, including primary immune deficiencies, autoimmune conditions, infections, cancers and mental disorder have been found to be associated with this region. However, due to a high ...

  19. It's the peptide-MHC affinity, stupid.

    Science.gov (United States)

    Kammertoens, Thomas; Blankenstein, Thomas

    2013-04-15

    Adoptively transferred T cells can reject large established tumors, but recurrence due to escape variants frequently occurs. In this issue of Cancer Cell, Engels et al. demonstrate that the affinity of the target peptide to the MHC molecule determines whether large tumors will relapse following adoptive T cell therapy. Copyright © 2013 Elsevier Inc. All rights reserved.

  20. The MHC molecules of nonmammalian vertebrates

    DEFF Research Database (Denmark)

    Kaufman, J; Skjoedt, K; Salomonsen, J

    1990-01-01

    class II distribution. The axolotl has a very poor immune response (as though there are no helper T cells), a wide class II distribution and, for most animals, no cell surface class I molecule. It would be enlightening to understand both the mechanisms for the regulation of the MHC molecules during...

  1. B-G cDNA clones have multiple small repeats and hybridize to both chicken MHC regions

    DEFF Research Database (Denmark)

    Kaufman, J; Salomonsen, J; Skjødt, K

    1989-01-01

    We used rabbit antisera to the chicken MHC erythrocyte molecule B-G and to the class I alpha chain (B-F) to screen lambda gt11 cDNA expression libraries made with RNA selected by oligo-dT from bone marrow cells of anemic B19 homozygous chickens. Eight clones were found to encode B-G molecules which...

  2. A monoclonal antibody distinguishes between two IgM heavy chain isotypes in Atlantic salmon and brown trout: protein characterization, 3D modeling and epitope mapping.

    Science.gov (United States)

    Kamil, Atif; Falk, Knut; Sharma, Animesh; Raae, Arnt; Berven, Frode; Koppang, Erling Olaf; Hordvik, Ivar

    2011-09-01

    Atlantic salmon (Salmo salar) and brown trout (Salmo trutta) possess two distinct subpopulations of IgM which can be separated by anion exchange chromatography. Accordingly, there are two isotypic μ genes in these species, related to ancestral tetraploidy. In the present work it was verified by mass spectrometry that IgM of peak 1 (subpopulation 1) have heavy chains previously designated as μB type whereas IgM of peak 2 (subpopulation 2) have heavy chains of μA type. Two adjacent cysteine residues are present near the C-terminal part of μB, in contrast to one cysteine residue in μA. Salmon IgM of both peak 1 and peak 2 contain light chains of the two most common isotypes: IgL1 and IgL3. In contrast to salmon and brown trout, IgM of rainbow trout (Oncorhynchus mykiss) is eluted in a single peak when subjected to anion exchange chromatography. Surprisingly, a monoclonal antibody MAb4C10 against rainbow trout IgM, reacted with μA in salmon, whereas in brown trout it reacted with μB. It is plausible to assume that DNA has been exchanged between the paralogous A and B loci during evolution while maintaining the two sub-variants, with and without the extra cysteine. MAb4C10 was conjugated to magnetic beads and used to separate cells, demonstrating that μ transcripts residing from captured cells were primarily of A type in salmon and B type in brown trout. An analysis of amino acid substitutions in μA and μB of salmon and brown trout indicated that the third constant domain is essential for MAb4C10 binding. This was supported by 3D modeling and was finally verified by studies of MAb4C10 reactivity with a series of recombinant μ3 constructs. Copyright © 2011 Elsevier Ltd. All rights reserved.

  3. Heavy metal concentrations in a soil-plant-snail food chain along a terrestrial soil pollution gradient.

    NARCIS (Netherlands)

    Notten, M.J.M.; Oosthoek, A.; Rozema, J.; Aerts, R.

    2005-01-01

    We investigated concentrations of Zn, Cu, Cd and Pb in the compartments of a soil-plant (Urtica dioica)-snail (Cepaea nemoralis) food chain in four polluted locations in the Biesbosch floodplains, the Netherlands, and two reference locations. Total soil metal concentrations in the polluted locations

  4. Distinct spatial relationship of interleukin-9 receptor with IL-2R and MHC glycoproteins in human T lymphoma cells

    OpenAIRE

    Nizsalóczki, Enikő; Csomós, István; Nagy, Péter; Fazekas, Zsolt; Goldman, Carolyn K.; Waldmann, Thomas A.; Damjanovich, Sándor; Vámosi, György; Mátyus, László; Bodnár, Andrea

    2014-01-01

    The IL-9R consists of the α-subunit and the γc-chain shared with other cytokine receptors, including IL-2R, an important regulator of T cells. We have previously shown that IL-2R is expressed in common clusters with MHC glycoproteins in lipid rafts of human T lymphoma cells raising the question what the relationship between clusters of IL-2R/MHC and IL-9R is. Confocal microscopic co-localization and FRET experiments capable of detecting membrane protein organization at different size scales r...

  5. MHC-like molecules in some nonmammalian vertebrates can be detected by some cross-reactive xenoantisera

    DEFF Research Database (Denmark)

    Kaufman, J; Skjoedt, K; Salomonsen, J

    1990-01-01

    in the contact regions between the chains. These latter antibodies recognized biosynthetic intermediates and also a variety of unusual cell surface MHC-like molecules present in reptile and amphibian, but absent in the mammal and chicken cells tested. These included E homodimers whose relationship to chicken B......-G molecules is unknown. 5) MHC-like molecules were identified in a bird, three reptiles, and two amphibians, but no molecules with the expected properties were found with these reagents in any of the fish tested. Udgivelsesdato: 1990-Mar-15...

  6. The combination of major histocompatibility complex (MHC) and non-MHC genes influences murine lymphocytic choriomeningitis virus pathogenesis

    DEFF Research Database (Denmark)

    Eyler, Y L; Pfau, C J; Broomhall, K S

    1989-01-01

    with the recessive disease phenotype. In all cases, susceptibility was dominant. In backcross progeny obtained from matings of parental strains differing in both major histocompatibility complex (MHC) and non-MHC (SWR; C3H), 90% of the challenged mice died, indicating that at least three loci controlled...... susceptibility to the disease. When the parental strains carried similar MHC haplotypes but dissimilar background genes (B10.BR; CBA), 78% of the backcross mice succumbed, indicating that at least two non-MHC loci influenced disease susceptibility. It is unlikely, however, that the same two non-MHC loci...... are critical in all genetic combinations, since F1 produced from two H-2 identical, resistant strains (B10.BR; C3H) were found to be fully susceptible. When congenic mice, differing only in the D-end of the MHC region, were analysed, 50% of the backcross animals died, indicating that one gene in the MHC region...

  7. Comparison of myosin heavy chain mRNAs, protein isoforms and fiber type proportions in the rat slow and fast muscles

    Czech Academy of Sciences Publication Activity Database

    Žurmanová, J.; Soukup, Tomáš

    2013-01-01

    Roč. 62, č. 4 (2013), s. 445-453 ISSN 0862-8408 R&D Projects: GA ČR(CZ) GA304/08/0256; GA ČR(CZ) GA305/09/1228; GA MŠk(CZ) 7AMB12SK158; GA MŠk(CZ) LH12058 Grant - others:EC(XE) LSH-CT-2004-511978 Institutional research plan: CEZ:AV0Z50110509 Institutional support: RVO:67985823 Keywords : rat * soleus * extensor digitorum longus * myosin heavy chain isoforms * muscle gene expression * quantitative Real Time RT-PCR * SDS - PAGE * fiber type analysis Subject RIV: EA - Cell Biology Impact factor: 1.487, year: 2013

  8. Efficient heterologous expression and secretion in Aspergillus oryzae of a llama variable heavy-chain antibody fragment V(HH) against EGFR.

    Science.gov (United States)

    Okazaki, Fumiyoshi; Aoki, Jun-ichi; Tabuchi, Soichiro; Tanaka, Tsutomu; Ogino, Chiaki; Kondo, Akihiko

    2012-10-01

    We have constructed a filamentous fungus Aspergillus oryzae that secretes a llama variable heavy-chain antibody fragment (V(HH)) that binds specifically to epidermal growth factor receptor (EGFR) in a culture medium. A major improvement in yield was achieved by fusing the V(HH) with a Taka-amylase A signal sequence (sTAA) and a segment of 28 amino acids from the N-terminal region of Rhizopus oryzae lipase (N28). The yields of secreted, immunologically active anti-EGFR V(HH) reached 73.8 mg/1 in a Sakaguchi flask. The V(HH) fragments were released from the sTAA or N28 proteins by an indigenous A. oryzae protease during cultivation. The purified recombinant V(HH) fragment was specifically recognized and could bind to the EGFR with a high affinity.

  9. Immunoglobulin heavy and light chains and T-cell receptor beta and gamma chains PCR assessment on cytological samples. A study comparing FTA cards and cryopreserved lymph node fine-needle cytology.

    Science.gov (United States)

    Peluso, A L; Cozzolino, I; Bottiglieri, A; Lucchese, L; Di Crescenzo, R M; Langella, M; Selleri, C; Zeppa, P

    2017-06-01

    To evaluate and compare the DNA yield and quality extracted from lymph node fine needle cytology (FNC) samples stored on FTA cards to those cryopreserved, and to assess the immunoglobulin heavy and light chains (IGHK) and T-Cell receptor beta and gamma chains (TCRBG) PCR tests. DNA extractions were performed on FNC of 80 non-Hodgkin lymphomas (NHL), four myelomas and 56 benign reactive hyperplasias (BRH) cryopreserved and stored on FTA cards. The JAK2 gene was amplified to assess the DNA integrity and the IGHK/TCRBG clonality status was tested. IGHK monoclonality was found in 99% of B-cell NHL and 100% of myeloma. TCRBG monoclonality was found in 100% of T-cell NHL. TCRBG polyclonality was detected in 97% of B-cell NHL, 100% of myeloma and 96% of BRH. IGHK/TCRBG PCR data were confirmed by histological and/or follow-up controls. No differences were found in the DNA quality between cryopreservation and FTA cards storage methods. IGHK/TCRBG PCR of the lymphoproliferative process on FTA cards is comparable to those cryopreserved. FTA cards can be used to store lymph node FNC for further molecular investigations. © 2016 John Wiley & Sons Ltd.

  10. Ligation of major histocompatibility complex class I antigens (MHC-I) prevents apoptosis induced by Fas or SAPK/JNK activation in T-lymphoma cells

    DEFF Research Database (Denmark)

    Lamberth, K; Claesson, M H

    2001-01-01

    Early apoptosis in Jurkat T-lymphoma cells was induced by agonistic anti-Fas Ab or by anisomycin which activates the stress kinases SAPK/JNK. Apoptosis was inhibited by ligation of major histocompatibility complex class I antigens (MHC-I). MHC-I ligation induced upregulation of the anti......-apoptotic Bcl-2 protein and stabilized the mitochondrial membrane potential (Deltapsim). MHC-I ligation also prevented downregulation of Bcl-2 and destabilization of Deltapsim induced by anti-Fas Ab treatment or anisomycin exposure. Studies on three different Jurkat cell mutants deficient for src p56(lck), ZAP......-70 kinase, or TCR/CD3 gamma-chain showed that the cells undergo apoptosis after Fas ligation. Anisomycin exposure induced apoptosis in the src p56(lck)-deficient cell line but not in the two other mutant cell lines. Simultaneous cross-linking of MHC-I and Fas ligation inhibited apoptosis in the ZAP...

  11. DNA sequence of the Peromyscus leucopus MHC class II gene Aa (MhcPeleAa)

    Energy Technology Data Exchange (ETDEWEB)

    Crew, M.D.; Bates, L.M. [Univ. of Arkansas for Medical Sciences, Little Rock, AR (United States)

    1996-09-01

    The genus Peromyscus has been extensively studied by populations biologists and ecologists for over eighty years, with P. leucopus (the white-footed mouse) being one of the most intensively investigated species. Polymorphic major histocompatibility complex (MHC) genes have proven useful in population genetic studies and might be helpful in understanding the population dynamics of Peromyscus species which are ubiquitously distributed over North and Central America. Polymorphism of P. leucopus MHC (MhcPele) class II genes was evident by restriction fragment length polymorphism (RFLP) analyses using human and mouse probes and Pele class II loci exhibited degrees of polymorphism similar to H2 class II genes (A-like>E-like). 8 refs., 2 figs.

  12. Immunoglobulin heavy-chain fluorescence in situ hybridization-chromogenic in situ hybridization DNA probe split signal in the clonality assessment of lymphoproliferative processes on cytological samples.

    Science.gov (United States)

    Zeppa, Pio; Sosa Fernandez, Laura Virginia; Cozzolino, Immacolata; Ronga, Valentina; Genesio, Rita; Salatiello, Maria; Picardi, Marco; Malapelle, Umberto; Troncone, Giancarlo; Vigliar, Elena

    2012-12-25

    The human immunoglobulin heavy-chain (IGH) locus at chromosome 14q32 is frequently involved in different translocations of non-Hodgkin lymphoma (NHL), and the detection of any breakage involving the IGH locus should identify a B-cell NHL. The split-signal IGH fluorescence in situ hybridization-chromogenic in situ hybridization (FISH-CISH) DNA probe is a mixture of 2 fluorochrome-labeled DNAs: a green one that binds the telomeric segment and a red one that binds the centromeric segment, both on the IGH breakpoint. In the current study, the authors tested the capability of the IGH FISH-CISH DNA probe to detect IGH translocations and diagnose B-cell lymphoproliferative processes on cytological samples. Fifty cytological specimens from cases of lymphoproliferative processes were tested using the split-signal IGH FISH-CISH DNA probe and the results were compared with light-chain assessment by flow cytometry (FC), IGH status was tested by polymerase chain reaction (PCR), and clinicohistological data. The signal score produced comparable results on FISH and CISH analysis and detected 29 positive, 15 negative, and 6 inadequate cases; there were 29 true-positive cases (66%), 9 true-negative cases (20%), 6 false-negative cases (14%), and no false-positive cases (0%). Comparing the sensitivity of the IGH FISH-CISH DNA split probe with FC and PCR, the highest sensitivity was obtained by FC, followed by FISH-CISH and PCR. The split-signal IGH FISH-CISH DNA probe is effective in detecting any translocation involving the IGH locus. This probe can be used on different samples from different B-cell lymphoproliferative processes, although it is not useful for classifying specific entities. Cancer (Cancer Cytopathol) 2012;. © 2012 American Cancer Society. Copyright © 2012 American Cancer Society.

  13. Primary structure of bovine calpactin I heavy chain (p36), a major cellular substrate for retroviral protein-tyrosine kinases: homology with the human phospholipase A2 inhibitor lipocortin

    DEFF Research Database (Denmark)

    Kristensen, Torsten; Sarin, C J; Hunter, T

    1986-01-01

    An amplified Okayama-Berg plasmid cDNA library was constructed from total poly(A)+ RNA isolated from the Madin-Darby bovine kidney cell line MDBK. This library was screened with a partial murine calpactin I heavy chain (p36) cDNA clone, the identification of which was based on bovine p36 tryptic ...

  14. MHCcluster, a method for functional clustering of MHC molecules

    DEFF Research Database (Denmark)

    Thomsen, Martin Christen Frølund; Lundegaard, Claus; Buus, Søren

    2013-01-01

    The identification of peptides binding to major histocompatibility complexes (MHC) is a critical step in the understanding of T cell immune responses. The human MHC genomic region (HLA) is extremely polymorphic comprising several thousand alleles, many encoding a distinct molecule. The potentially...... binding specificity. The method has a flexible web interface that allows the user to include any MHC of interest in the analysis. The output consists of a static heat map and graphical tree-based visualizations of the functional relationship between MHC variants and a dynamic TreeViewer interface where...

  15. Heavy metal concentrations in a soil-plant-snail food chain along a terrestrial soil pollution gradient

    Energy Technology Data Exchange (ETDEWEB)

    Notten, M.J.M. [Institute of Ecological Science, Department of Systems Ecology, Vrije Universiteit Amsterdam, De Boelelaan 1085, 1081 HV, Amsterdam (Netherlands)]. E-mail: martje.notten@ecology.falw.vu.nl; Oosthoek, A.J.P. [Institute of Ecological Science, Department of Systems Ecology, Vrije Universiteit Amsterdam, De Boelelaan 1085, 1081 HV, Amsterdam (Netherlands); Rozema, J. [Institute of Ecological Science, Department of Systems Ecology, Vrije Universiteit Amsterdam, De Boelelaan 1085, 1081 HV, Amsterdam (Netherlands); Aerts, R. [Institute of Ecological Science, Department of Systems Ecology, Vrije Universiteit Amsterdam, De Boelelaan 1085, 1081 HV, Amsterdam (Netherlands)

    2005-11-15

    We investigated concentrations of Zn, Cu, Cd and Pb in the compartments of a soil-plant (Urtica dioica)-snail (Cepaea nemoralis) food chain in four polluted locations in the Biesbosch floodplains, the Netherlands, and two reference locations. Total soil metal concentrations in the polluted locations were 4-20 times higher than those in the reference locations. Positive relationships between the generally low leaf concentrations and the soil concentrations were found for Zn only (r {sup 2} = 0.20). Bioaccumulation of Zn, Cu and Cd was observed in the snail tissues. We found positive relationships between the snail and leaf concentrations for all metals (range r {sup 2} = 0.19-0.46). The relationships between soil and snail concentrations were also positive, except for Cu (range r {sup 2} = 0.15-0.33). These results suggest transfer of metals to C. nemoralis snails from U. dioica leaves and from the soil. Metal transfer from polluted leaves to C. nemoralis is more important than transfer from the soil. - Bioaccumulation and positive snail-leaf relationships suggest metal transfer from Urtica dioica leaves to Cepaea nemoralis snails.

  16. Heavy metal concentrations in a soil-plant-snail food chain along a terrestrial soil pollution gradient

    International Nuclear Information System (INIS)

    Notten, M.J.M.; Oosthoek, A.J.P.; Rozema, J.; Aerts, R.

    2005-01-01

    We investigated concentrations of Zn, Cu, Cd and Pb in the compartments of a soil-plant (Urtica dioica)-snail (Cepaea nemoralis) food chain in four polluted locations in the Biesbosch floodplains, the Netherlands, and two reference locations. Total soil metal concentrations in the polluted locations were 4-20 times higher than those in the reference locations. Positive relationships between the generally low leaf concentrations and the soil concentrations were found for Zn only (r 2 = 0.20). Bioaccumulation of Zn, Cu and Cd was observed in the snail tissues. We found positive relationships between the snail and leaf concentrations for all metals (range r 2 = 0.19-0.46). The relationships between soil and snail concentrations were also positive, except for Cu (range r 2 = 0.15-0.33). These results suggest transfer of metals to C. nemoralis snails from U. dioica leaves and from the soil. Metal transfer from polluted leaves to C. nemoralis is more important than transfer from the soil. - Bioaccumulation and positive snail-leaf relationships suggest metal transfer from Urtica dioica leaves to Cepaea nemoralis snails

  17. MPID-T2: a database for sequence-structure-function analyses of pMHC and TR/pMHC structures.

    Science.gov (United States)

    Khan, Javed Mohammed; Cheruku, Harish Reddy; Tong, Joo Chuan; Ranganathan, Shoba

    2011-04-15

    Sequence-structure-function information is critical in understanding the mechanism of pMHC and TR/pMHC binding and recognition. A database for sequence-structure-function information on pMHC and TR/pMHC interactions, MHC-Peptide Interaction Database-TR version 2 (MPID-T2), is now available augmented with the latest PDB and IMGT/3Dstructure-DB data, advanced features and new parameters for the analysis of pMHC and TR/pMHC structures. http://biolinfo.org/mpid-t2. shoba.ranganathan@mq.edu.au Supplementary data are available at Bioinformatics online.

  18. The SysteMHC Atlas project

    DEFF Research Database (Denmark)

    Shao, Wenguang; Pedrioli, Patrick G. A.; Wolski, Witold

    2018-01-01

    consisting of consensus spectra calculated from repeat measurements of the same peptide sequence, and links to other proteomics and immunology databases. The SysteMHC Atlas project was created and will be further expanded using a uniform and open computational pipeline that controls the quality of peptide......-scale generation of immunopeptidomic datasets and recent developments in MS-based peptide analysis technologies now support the generation of the required data. Importantly, the availability of diverse immunopeptidomic datasets has resulted in an increasing need to standardize, store and exchange this type of data...

  19. Frequent expression loss of Inter-alpha-trypsin inhibitor heavy chain (ITIH) genes in multiple human solid tumors: A systematic expression analysis

    International Nuclear Information System (INIS)

    Hamm, Alexander; Knuechel, Ruth; Dahl, Edgar; Veeck, Juergen; Bektas, Nuran; Wild, Peter J; Hartmann, Arndt; Heindrichs, Uwe; Kristiansen, Glen; Werbowetski-Ogilvie, Tamra; Del Maestro, Rolando

    2008-01-01

    The inter-alpha-trypsin inhibitors (ITI) are a family of plasma protease inhibitors, assembled from a light chain – bikunin, encoded by AMBP – and five homologous heavy chains (encoded by ITIH1, ITIH2, ITIH3, ITIH4, and ITIH5), contributing to extracellular matrix stability by covalent linkage to hyaluronan. So far, ITIH molecules have been shown to play a particularly important role in inflammation and carcinogenesis. We systematically investigated differential gene expression of the ITIH gene family, as well as AMBP and the interacting partner TNFAIP6 in 13 different human tumor entities (of breast, endometrium, ovary, cervix, stomach, small intestine, colon, rectum, lung, thyroid, prostate, kidney, and pancreas) using cDNA dot blot analysis (Cancer Profiling Array, CPA), semiquantitative RT-PCR and immunohistochemistry. We found that ITIH genes are clearly downregulated in multiple human solid tumors, including breast, colon and lung cancer. Thus, ITIH genes may represent a family of putative tumor suppressor genes that should be analyzed in greater detail in the future. For an initial detailed analysis we chose ITIH2 expression in human breast cancer. Loss of ITIH2 expression in 70% of cases (n = 50, CPA) could be confirmed by real-time PCR in an additional set of breast cancers (n = 36). Next we studied ITIH2 expression on the protein level by analyzing a comprehensive tissue micro array including 185 invasive breast cancer specimens. We found a strong correlation (p < 0.001) between ITIH2 expression and estrogen receptor (ER) expression indicating that ER may be involved in the regulation of this ECM molecule. Altogether, this is the first systematic analysis on the differential expression of ITIH genes in human cancer, showing frequent downregulation that may be associated with initiation and/or progression of these malignancies

  20. Frequent expression loss of Inter-alpha-trypsin inhibitor heavy chain (ITIH genes in multiple human solid tumors: A systematic expression analysis

    Directory of Open Access Journals (Sweden)

    Werbowetski-Ogilvie Tamra

    2008-01-01

    Full Text Available Abstract Background The inter-alpha-trypsin inhibitors (ITI are a family of plasma protease inhibitors, assembled from a light chain – bikunin, encoded by AMBP – and five homologous heavy chains (encoded by ITIH1, ITIH2, ITIH3, ITIH4, and ITIH5, contributing to extracellular matrix stability by covalent linkage to hyaluronan. So far, ITIH molecules have been shown to play a particularly important role in inflammation and carcinogenesis. Methods We systematically investigated differential gene expression of the ITIH gene family, as well as AMBP and the interacting partner TNFAIP6 in 13 different human tumor entities (of breast, endometrium, ovary, cervix, stomach, small intestine, colon, rectum, lung, thyroid, prostate, kidney, and pancreas using cDNA dot blot analysis (Cancer Profiling Array, CPA, semiquantitative RT-PCR and immunohistochemistry. Results We found that ITIH genes are clearly downregulated in multiple human solid tumors, including breast, colon and lung cancer. Thus, ITIH genes may represent a family of putative tumor suppressor genes that should be analyzed in greater detail in the future. For an initial detailed analysis we chose ITIH2 expression in human breast cancer. Loss of ITIH2 expression in 70% of cases (n = 50, CPA could be confirmed by real-time PCR in an additional set of breast cancers (n = 36. Next we studied ITIH2 expression on the protein level by analyzing a comprehensive tissue micro array including 185 invasive breast cancer specimens. We found a strong correlation (p Conclusion Altogether, this is the first systematic analysis on the differential expression of ITIH genes in human cancer, showing frequent downregulation that may be associated with initiation and/or progression of these malignancies.

  1. Ligation of major histocompatibility complex class I antigens (MHC-I) prevents apoptosis induced by Fas or SAPK/JNK activation in T-lymphoma cells

    DEFF Research Database (Denmark)

    Lamberth, K; Claesson, M H

    2001-01-01

    Early apoptosis in Jurkat T-lymphoma cells was induced by agonistic anti-Fas Ab or by anisomycin which activates the stress kinases SAPK/JNK. Apoptosis was inhibited by ligation of major histocompatibility complex class I antigens (MHC-I). MHC-I ligation induced upregulation of the anti-apoptotic......Early apoptosis in Jurkat T-lymphoma cells was induced by agonistic anti-Fas Ab or by anisomycin which activates the stress kinases SAPK/JNK. Apoptosis was inhibited by ligation of major histocompatibility complex class I antigens (MHC-I). MHC-I ligation induced upregulation of the anti......-apoptotic Bcl-2 protein and stabilized the mitochondrial membrane potential (Deltapsim). MHC-I ligation also prevented downregulation of Bcl-2 and destabilization of Deltapsim induced by anti-Fas Ab treatment or anisomycin exposure. Studies on three different Jurkat cell mutants deficient for src p56(lck), ZAP......-70 kinase, or TCR/CD3 gamma-chain showed that the cells undergo apoptosis after Fas ligation. Anisomycin exposure induced apoptosis in the src p56(lck)-deficient cell line but not in the two other mutant cell lines. Simultaneous cross-linking of MHC-I and Fas ligation inhibited apoptosis in the ZAP...

  2. Structure of the superantigen staphylococcal enterotoxin B in complex with TCR and peptide-MHC demonstrates absence of TCR-peptide contacts.

    Science.gov (United States)

    Rödström, Karin E J; Elbing, Karin; Lindkvist-Petersson, Karin

    2014-08-15

    Superantigens are immune-stimulatory toxins produced by Staphylococcus aureus, which are able to interact with host immune receptors to induce a massive release of cytokines, causing toxic shock syndrome and possibly death. In this article, we present the x-ray structure of staphylococcal enterotoxin B (SEB) in complex with its receptors, the TCR and MHC class II, forming a ternary complex. The structure, in combination with functional analyses, clearly shows how SEB adopts a wedge-like position when binding to the β-chain of TCR, allowing for an interaction between the α-chain of TCR and MHC. Furthermore, the binding mode also circumvents contact between TCR and the peptide presented by MHC, which enables SEB to initiate a peptide-independent activation of T cells. Copyright © 2014 by The American Association of Immunologists, Inc.

  3. The systems biology of MHC class II antigen presentation

    NARCIS (Netherlands)

    Paul, Petra

    2012-01-01

    Major histocompatibility class II molecules (MHC class II) are one of the key regulators of adaptive immunity because of their specific expression by professional antigen presenting cells (APC). They present peptides derived from endocytosed material to T helper lymphocytes. Consequently, MHC class

  4. MHC class II molecules and tumour immunotherapy

    International Nuclear Information System (INIS)

    Oven, I.

    2005-01-01

    Background. Tumour immunotherapy attempts to use the specificity and capability of the immune system to kill malignant cells with a minimum damage to normal tissue. Increasing knowledge of the identity of tumour antigens should help us design more effective therapeutic vaccines. Increasing evidence has demonstrated that MHC class II molecules and CD4+ T cells play important roles in generating and maintaining antitumour immune responses in animal models. These data suggest that it may be necessary to involve both CD4+ and CD8+ T cells for more effective antitumour therapy. Novel strategies have been developed for enhancing T cell responses against cancer by prolonging antigen presentation of dendritic cells to T cells, by the inclusion of MHC class II-restricted tumour antigens and by genetically modifying tumour cells to present antigen to T lymphocytes directly. Conclusions. Vaccines against cancers aim to induce tumour-specific effector T cells that can reduce tumour mass and induce development of tumour-specific T cell memory, that can control tumour relapse. (author)

  5. Identification of high-mannose and multiantennary complex-type N-linked glycans containing alpha-galactose epitopes from Nurse shark IgM heavy chain.

    Science.gov (United States)

    Harvey, David J; Crispin, Max; Moffatt, Beryl E; Smith, Sylvia L; Sim, Robert B; Rudd, Pauline M; Dwek, Raymond A

    2009-11-01

    MALDI-TOF mass spectrometry, negative ion nano-electrospray MS/MS and exoglycosidase digestion were used to identify 36 N-linked glycans from 19S IgM heavy chain derived from the nurse shark (Ginglymostoma cirratum). The major glycan was the high-mannose compound, Man(6)GlcNAc(2) accompanied by small amounts of Man(5)GlcNAc(2), Man(7)GlcNAc(2) and Man(8)GlcNAc(2). Bi- and tri-antennary (isomer with a branched 3-antenna) complex-type glycans were also abundant, most contained a bisecting GlcNAc residue (beta1-->4-linked to the central mannose) and with varying numbers of alpha-galactose residues capping the antennae. Small amounts of monosialylated glycans were also found. This appears to be the first comprehensive study of glycosylation in this species of animal. The glycosylation pattern has implications for the mechanism of activation of the complement system by nurse shark IgM.

  6. Passive Repetitive Stretching for a Short Duration within a Week Increases Myogenic Regulatory Factors and Myosin Heavy Chain mRNA in Rats' Skeletal Muscles

    Directory of Open Access Journals (Sweden)

    Yurie Kamikawa

    2013-01-01

    Full Text Available Stretching is a stimulation of muscle growth. Stretching for hours or days has an effect on muscle hypertrophy. However, differences of continuous stretching and repetitive stretching to affect muscle growth are not well known. To clarify the difference of continuous and repetitive stretching within a short duration, we investigated the gene expression of muscle-related genes on stretched skeletal muscles. We used 8-week-old male Wistar rats ( for this study. Animals medial gastrocnemius muscle was stretched continuously or repetitively for 15 min daily and 4 times/week under anesthesia. After stretching, muscles were removed and total RNA was extracted. Then, reverse transcriptional quantitative real-time PCR was done to evaluate the mRNA expression of MyoD, myogenin, and embryonic myosin heavy chain (MyHC. Muscles, either stretched continuously or repetitively, increased mRNA expression of MyoD, myogenin, and embryonic MyHC more than unstretched muscles. Notably, repetitive stretching resulted in more substantial effects on embryonic MyHC gene expression than continuous stretching. In conclusion, passive stretching for a short duration within a week is effective in increasing myogenic factor expression, and repetitive stretching had more effects than continuous stretching for skeletal muscle on muscle growth. These findings are applicable in clinical muscle-strengthening therapy.

  7. Effects of hypothyroidism on myosin heavy chain composition and fibre types of fast skeletal muscles in a small marsupial, Antechinus flavipes.

    Science.gov (United States)

    Zhong, Wendy W H; Withers, Kerry W; Hoh, Joseph F Y

    2010-04-01

    Effects of drug-induced hypothyroidism on myosin heavy chain (MyHC) content and fibre types of fast skeletal muscles were studied in a small marsupial, Antechinus flavipes. SDS-PAGE of MyHCs from the tibialis anterior and gastrocnemius revealed four isoforms, 2B, 2X, 2A and slow, in that order of decreasing abundance. After 5 weeks treatment with methimazole, the functionally fastest 2B MyHC significantly decreased, while 2X, 2A and slow MyHCs increased. Immunohistochemistry using monospecific antibodies to each of the four MyHCs revealed decreased 2b and 2x fibres, and increased 2a and hybrid fibres co-expressing two or three MyHCs. In the normally homogeneously fast superficial regions of these muscles, evenly distributed slow-staining fibres appeared, resembling the distribution of slow primary myotubes in fast muscles during development. Hybrid fibres containing 2A and slow MyHCs were virtually absent. These results are more detailed but broadly similar to the earlier studies on eutherians. We hypothesize that hypothyroidism essentially reverses the effects of thyroid hormone on MyHC gene expression of muscle fibres during myogenesis, which differ according to the developmental origin of the fibre: it induces slow MyHC expression in 2b fibres derived from fast primary myotubes, and shifts fast MyHC expression in fibres of secondary origin towards 2A, but not slow, MyHC.

  8. The importance of subfragment 2 and C-terminus of myosin heavy chain for thick filament assembly in skeletal muscle cells.

    Science.gov (United States)

    Ojima, Koichi; Oe, Mika; Nakajima, Ikuyo; Shibata, Masahiro; Muroya, Susumu; Chikuni, Koichi; Hattori, Akihito; Nishimura, Takanori

    2015-04-01

    In skeletal muscle cells, myofibrillar proteins are highly organized into sarcomeres in which thick filaments interdigitate with thin filaments to generate contractile force. The size of thick filaments, which consist mainly of myosin molecules, is strictly controlled. However, little is known about the mechanisms by which myosin molecules assemble into thick filaments. Here, we assessed the ability of each domain of myosin heavy chain (Myh) to form thick filaments. We showed that exogenously expressed subfragment 2 (S2) + light meromyosin (LMM) of Myh was efficiently incorporated into thick filaments in muscle cells, although neither solely expressed S2 nor LMM targeted to thick filaments properly. In nonmuscle COS7 cells, S2+LMM formed more enlarged filaments/speckles than LMM. These results suggest that Myh filament formation is induced by S2 accompanying LMM. We further examined the effects of Myh C-terminus on thick filament assembly. C-terminal deletion mutants were incorporated not into entire thick filaments but rather into restricted regions of thick filaments. Our findings suggest that the elongation of myosin filaments to form thick filaments is regulated by S2 as well as C-terminus of LMM. © 2014 Japanese Society of Animal Science.

  9. Different regions of the immunoglobulin heavy-chain locus are involved in chromosomal translocations in distinct pathogenic forms of Burkitt lymphoma

    Energy Technology Data Exchange (ETDEWEB)

    Neri, A.; Barriga, F.; Knowles, D.M.; Magrath, I.T.; Dalla-Favera, R.

    1988-04-01

    The authors show that endemic (eBL), sporadic (sBL), and acquired immunodeficiency syndrome-associated (AIDS-BL) forms of Burkitt lymphoma (BL) carrying t(8; 14) chromosomal translocations display different breakpoints within the immunoglobulin heavy-chain locus (IGH) on chromosome 14. In sBL (7 out of 11) and AIDS-BL (5 out of 6), the breakpoints occurred within or near the IGH ..mu.. switch (S/sub mu/) region on chromosome 14 and within the c-myc locus (MYC) on chromosome 8. In most eBL (13 out of 16) the breakpoints were mapped within or 5' to the IGH joining J/sub H/ region on chromosome 14 and outside the MYC locus on chromosome 8. Cloning and sequencing of the (8; 14) chromosomal junctions from two eBL cell lines and one eBL biopsy sample show that the recombination do not involve IGH-specific recombination signals on chromosome 14 or homologous sequences on chromosome 8, suggesting that these events are not likely to be mediated by the same mechanisms or enzymes as in IGH rearrangements. In general, these data have implications for the timing of occurrence of chromosomal translocations during B-cell differentiation in different BL types.

  10. Aspirin and salicylate bind to immunoglobulin heavy chain binding protein (BiP) and inhibit its ATPase activity in human fibroblasts.

    Science.gov (United States)

    Deng, W G; Ruan, K H; Du, M; Saunders, M A; Wu, K K

    2001-11-01

    Salicylic acid (SA), an endogenous signaling molecule of plants, possesses anti-inflammatory and anti-neoplastic actions in human. Its derivative, aspirin, is the most commonly used anti-inflammatory and analgesic drug. Aspirin and sodium salicylate (salicylates) have been reported to have multiple pharmacological actions. However, it is unclear whether they bind to a cellular protein. Here, we report for the first time the purification from human fibroblasts of a approximately 78 kDa salicylate binding protein with sequence identity to immunoglobulin heavy chain binding protein (BiP). The Kd values of SA binding to crude extract and to recombinant BiP were 45.2 and 54.6 microM, respectively. BiP is a chaperone protein containing a polypeptide binding site recognizing specific heptapeptide sequence and an ATP binding site. A heptapeptide with the specific sequence displaced SA binding in a concentration-dependent manner whereas a control heptapeptide did not. Salicylates inhibited ATPase activity stimulated by this specific heptapeptide but did not block ATP binding or induce BiP expression. These results indicate that salicylates bind specifically to the polypeptide binding site of BiP in human cells that may interfere with folding and transport of proteins important in inflammation.

  11. Proteomic demonstration of the recurrent presence of inter-alpha-inhibitor H4 heavy-chain during aspergillosis induced in an animal model.

    Science.gov (United States)

    Desoubeaux, Guillaume; Jourdan, Marie-Lise; Valera, Lionel; Jardin, Bénédicte; Hem, Sonia; Caille, Agnès; Cormier, Bénédicte; Marchand-Adam, Sylvain; Bailly, Éric; Diot, Patrice; Chandenier, Jacques

    2014-05-01

    Invasive pulmonary aspergillosis remains a matter of great concern in oncology/haematology, intensive care units and organ transplantation departments. Despite the availability of various diagnostic tools with attractive features, new markers of infection are required for better medical care. We therefore looked for potential pulmonary biomarkers of aspergillosis, by carrying out two-dimensional (2D) gel electrophoresis comparing the proteomes of bronchial-alveolar lavage fluids (BALF) from infected rats and from control rats presenting non-specific inflammation, both immunocompromised. A bioinformatic analysis of the 2D-maps revealed significant differences in the abundance of 20 protein spots (ANOVA P-valuevalue0.8). One of these proteins, identified by mass spectrometry, was considered of potential interest: inter-alpha-inhibitor H4 heavy-chain (ITIH4), characterised for the first time in this infectious context. Western blotting confirmed its overabundance in all infected BALF, particularly at early stages of murine aspergillosis. Further investigations were carried on rat serum, and confirmed that ITIH4 levels increased during experimental aspergillosis. Preliminary results in human samples strengthened this trend. To our knowledge, this is the first description of the involvement of ITIH4 in aspergillosis. Copyright © 2013 Elsevier GmbH. All rights reserved.

  12. Colonizing the world in spite of reduced MHC variation

    Science.gov (United States)

    Gangoso, L.; Alcaide, M.; Grande, J.M.; Muñoz, J.; Talbot, Sandra L.; Sonsthagen, Sarah A.; Sage, Kevin; Figuerola, J.

    2012-01-01

    Reduced immune gene diversity is thought to negatively affect the capacity of organisms to adapt to pathogen challenges, which represent a major force in natural selection. Genes of the Major Histocompatibility Complex (MHC) are the most widely invoked adaptive loci in conservation biology, and have become the most popular genetic markers to investigate pathogen-host interactions in vertebrates. Although MHC genes are the most polymorphic genes described in the vertebrate genome, the extent to which MHC diversity determines the long-term persistence of populations is, unclear and often debated, as recent studies have documented the occurrence of natural populations thriving even after a depletion of MHC diversity caused by genetic drift. Here, we show that some phylogenetically related species belonging to the Falco genus (Aves: Falconidae) present a dramatically low MHC variability that has not precluded, nevertheless, the successful colonization of almost all existing regions and habitats worldwide. We found evidence for two remarkably different patterns of MHC variation within the genus. While kestrels show a high MHC variation according to the general theory, falcons exhibit an ancestrally low intra- and inter-specific MHC allelic diversity. We provide compelling evidence that this pattern is not caused by the degeneration of functional genes into pseudogenes, the inadvertent analyses of paralogous MHC genes, or the devastating action of genetic drift. Instead, our results strongly support the idea of an evolutionary transition driven and maintained by natural selection from primarily highly variable towards low polymorphic, but functional and expressed, MHC genes with species-specific pathogen-recognition capabilities.

  13. Sympatric and allopatric divergence of MHC genes in threespine stickleback.

    Directory of Open Access Journals (Sweden)

    Blake Matthews

    2010-06-01

    Full Text Available Parasites can strongly affect the evolution of their hosts, but their effects on host diversification are less clear. In theory, contrasting parasite communities in different foraging habitats could generate divergent selection on hosts and promote ecological speciation. Immune systems are costly to maintain, adaptable, and an important component of individual fitness. As a result, immune system genes, such as those of the Major Histocompatibility Complex (MHC, can change rapidly in response to parasite-mediated selection. In threespine stickleback (Gasterosteus aculeatus, as well as in other vertebrates, MHC genes have been linked with female mating preference, suggesting that divergent selection acting on MHC genes might influence speciation. Here, we examined genetic variation at MHC Class II loci of sticklebacks from two lakes with a limnetic and benthic species pair, and two lakes with a single species. In both lakes with species pairs, limnetics and benthics differed in their composition of MHC alleles, and limnetics had fewer MHC alleles per individual than benthics. Similar to the limnetics, the allopatric population with a pelagic phenotype had few MHC alleles per individual, suggesting a correlation between MHC genotype and foraging habitat. Using a simulation model we show that the diversity and composition of MHC alleles in a sympatric species pair depends on the amount of assortative mating and on the strength of parasite-mediated selection in adjacent foraging habitats. Our results indicate parallel divergence in the number of MHC alleles between sympatric stickleback species, possibly resulting from the contrasting parasite communities in littoral and pelagic habitats of lakes.

  14. Simulation of Major Histocompatibility Complex (MHC Structure and Peptide Loading into an MHC Binding Pocket with Teachers’Hands

    Directory of Open Access Journals (Sweden)

    Mojtaba Sankian

    2013-10-01

    Full Text Available Molecular understanding of three-dimensional (3D peptide: MHC models require both basic knowledge of computational modeling and skilled visual perception, which are not possessed by all students. The present model aims to simulate MHC molecular structure with the hands and make a profound impression on the students.

  15. Myosin heavy chain composition in the vastus lateralis muscle in relation to oxygen uptake and heart rate during cycling in humans.

    Science.gov (United States)

    Majerczak, J; Nieckarz, Z; Karasinski, J; Zoladz, J A

    2014-04-01

    In this study we examined the relationship between fast myosin heavy chain (MyHC2) content in the vastus lateralis and the rate of oxygen uptake (VO2) and heart rate (HR) increase during an incremental exercise in 38, young, healthy men. Prior to the exercise test, muscle biopsies were taken in order to evaluate the MyHC composition. It was found that during cycling performed below the lactate threshold (LT), a positive relationship between MyHC2 and the intercept of the oxygen uptake and power output (VO2-PO) relationship existed (r=0.49, P=0.002), despite no correlation between MyHC2 and the slope value of the VO2-PO relationship (r= -0.18, P=0.29). During cycling performed above the LT, MyHC2 correlated positively with the magnitude of the nonlinearity in the VO2-PO relationship; i.e. with the accumulated VO2'excess' (r=0.44, P=0.006) and peak VO2'excess' (r=0.44, P=0.006), as well as with the slope of the HR-PO relationship (r=0.49, P=0.002). We have concluded that a greater MyHC2 content in the vastus lateralis is accompanied by a higher oxygen cost of cycling during exercise performed below the LT. This seems to be related to the higher energy cost of the non-cross-bridge activities in the muscles possessing a greater proportion of MyHC2 content. In the case of heavy-intensity exercise, a higher MyHC2 content in the vastus lateralis is accompanied by greater non-linearity in the VO2-PO relationship, as well as a steeper increase in HR in the function of an increase of PO. This relationship can be explained by greater disturbances in metabolic stability in type II muscle fibres during exercise, resulting in a decrease of muscle mechanical efficiency and greater increase of heart rate at a given power output. Therefore, MyHC composition has an impact on the oxygen cost of cycling both below and above the LT.

  16. Methods for MHC genotyping in non-model vertebrates.

    Science.gov (United States)

    Babik, W

    2010-03-01

    Genes of the major histocompatibility complex (MHC) are considered a paradigm of adaptive evolution at the molecular level and as such are frequently investigated by evolutionary biologists and ecologists. Accurate genotyping is essential for understanding of the role that MHC variation plays in natural populations, but may be extremely challenging. Here, I discuss the DNA-based methods currently used for genotyping MHC in non-model vertebrates, as well as techniques likely to find widespread use in the future. I also highlight the aspects of MHC structure that are relevant for genotyping, and detail the challenges posed by the complex genomic organization and high sequence variation of MHC loci. Special emphasis is placed on designing appropriate PCR primers, accounting for artefacts and the problem of genotyping alleles from multiple, co-amplifying loci, a strategy which is frequently necessary due to the structure of the MHC. The suitability of typing techniques is compared in various research situations, strategies for efficient genotyping are discussed and areas of likely progress in future are identified. This review addresses the well established typing methods such as the Single Strand Conformation Polymorphism (SSCP), Denaturing Gradient Gel Electrophoresis (DGGE), Reference Strand Conformational Analysis (RSCA) and cloning of PCR products. In addition, it includes the intriguing possibility of direct amplicon sequencing followed by the computational inference of alleles and also next generation sequencing (NGS) technologies; the latter technique may, in the future, find widespread use in typing complex multilocus MHC systems. © 2009 Blackwell Publishing Ltd.

  17. Levels of myosin heavy chain mRNA transcripts and protein isoforms in the fast extensor digitorum longus muscle of 7-month-old rats with chronic thyroid status alterations

    Czech Academy of Sciences Publication Activity Database

    Vadászová, Adriana; Hudecová, S.; Križanová, O.; Soukup, Tomáš

    2006-01-01

    Roč. 55, č. 6 (2006), s. 707-710 ISSN 0862-8408 R&D Projects: GA ČR(CZ) GA304/05/0327 Grant - others:VEGA(SK) 2/4106; NATO(XE) 979876; SAV(SK) APVT-51-027404; MYORES(XE) 511978 Institutional research plan: CEZ:AV0Z50110509 Keywords : myosin heavy chain isoforms * thyroid hormones * muscle differentiation Subject RIV: ED - Physiology Impact factor: 2.093, year: 2006

  18. Improved pan-specific MHC class I peptide-binding predictions using a novel representation of the MHC-binding cleft environment

    DEFF Research Database (Denmark)

    Carrasco Pro, S.; Zimic, M.; Nielsen, Morten

    2014-01-01

    of the current state-of-the-art methods for MHC class I is NetMHCpan, which has a core ingredient for the representation of the MHC class I molecule using a pseudo-sequence representation of the binding cleft amino acid environment. New and large MHC-peptide-binding data sets are constantly being made available...... of different MHC data sets including human leukocyte antigen (HLA), non-human primates (chimpanzee, macaque and gorilla) and other animal alleles (cattle, mouse and swine). From these constructs, we showed that by focusing on MHC sequence positions found to be polymorphic across the MHC molecules used to train...

  19. A Genome-wide multidimensional RNAi screen reveals pathways controlling MHC class II antigen presentation

    NARCIS (Netherlands)

    Paul, Petra; van den Hoorn, Tineke; Jongsma, Marlieke L. M.; Bakker, Mark J.; Hengeveld, Rutger; Janssen, Lennert; Cresswell, Peter; Egan, David A.; van Ham, Marieke; ten Brinke, Anja; Ovaa, Huib; Beijersbergen, Roderick L.; Kuijl, Coenraad; Neefjes, Jacques

    2011-01-01

    MHC class II molecules (MHC-II) present peptides to T helper cells to facilitate immune responses and are strongly linked to autoimmune diseases. To unravel processes controlling MHC-II antigen presentation, we performed a genome-wide flow cytometry-based RNAi screen detecting MHC-II expression and

  20. Immunoglobulin Heavy Chain Variable Region and Major Histocompatibility Region Genes Are Linked to Induced Graves' Disease in Females From Two Very Large Families of Recombinant Inbred Mice

    Science.gov (United States)

    Aliesky, Holly; Banuelos, Bianca; Magana, Jessica; Williams, Robert W.; Rapoport, Basil

    2014-01-01

    Graves' hyperthyroidism is caused by antibodies to the TSH receptor (TSHR) that mimic thyroid stimulation by TSH. Stimulating TSHR antibodies and hyperthyroidism can be induced by immunizing mice with adenovirus expressing the human TSHR A-subunit. Prior analysis of induced Graves' disease in small families of recombinant inbred (RI) female mice demonstrated strong genetic control but did not resolve trait loci for TSHR antibodies or elevated serum T4. We investigated the genetic basis for induced Graves' disease in female mice of two large RI families and combined data with earlier findings to provide phenotypes for 178 genotypes. TSHR antibodies measured by inhibition of TSH binding to its receptor were highly significantly linked in the BXD set to the major histocompatibility region (chromosome 17), consistent with observations in 3 other RI families. In the LXS family, we detected linkage between T4 levels after TSHR-adenovirus immunization and the Ig heavy chain variable region (Igvh, chromosome 12). This observation is a key finding because components of the antigen binding region of Igs determine antibody specificity and have been previously linked to induced thyroid-stimulating antibodies. Data from the LXS family provide the first evidence in mice of a direct link between induced hyperthyroidism and Igvh genes. A role for major histocompatibility genes has now been established for genetic susceptibility to Graves' disease in both humans and mice. Future studies using arrays incorporating variation in the complex human Ig gene locus will be necessary to determine whether Igvh genes are also linked to Graves' disease in humans. PMID:25051451

  1. Nonmuscle myosin heavy chain IIA is a critical factor contributing to the efficiency of early infection of severe fever with thrombocytopenia syndrome virus.

    Science.gov (United States)

    Sun, Yinyan; Qi, Yonghe; Liu, Chenxuan; Gao, Wenqing; Chen, Pan; Fu, Liran; Peng, Bo; Wang, Haimin; Jing, Zhiyi; Zhong, Guocai; Li, Wenhui

    2014-01-01

    Severe fever with thrombocytopenia syndrome virus (SFTSV) is a novel phlebovirus in the Bunyaviridae family. Most patients infected by SFTSV present with fever and thrombocytopenia, and up to 30% die due to multiple-organ dysfunction. The mechanisms by which SFTSV enters multiple cell types are unknown. SFTSV contains two species of envelope glycoproteins, Gn (44.2 kDa) and Gc (56 kDa), both of which are encoded by the M segment and are cleaved from a precursor polypeptide (about 116 kDa) in the endoplasmic reticulum (ER). Gn fused with an immunoglobulin Fc tag at its C terminus (Gn-Fc) bound to multiple cells susceptible to the infection of SFTSV and blocked viral infection of human umbilical vein endothelial cells (HUVECs). Immunoprecipitation assays following mass spectrometry analysis showed that Gn binds to nonmuscle myosin heavy chain IIA (NMMHC-IIA), a cellular protein with surface expression in multiple cell types. Small interfering RNA (siRNA) knockdown of NMMHC-IIA, but not the closely related NMMHC-IIB or NMMHC-IIC, reduced SFTSV infection, and NMMHC-IIA specific antibody blocked infection by SFTSV but not other control viruses. Overexpression of NMMHC-IIA in HeLa cells, which show limited susceptivity to SFTSV, markedly enhanced SFTSV infection of the cells. These results show that NMMHC-IIA is critical for the cellular entry of SFTSV. As NMMHC-IIA is essential for the normal functions of platelets and human vascular endothelial cells, it is conceivable that NMMHC-IIA directly contributes to the pathogenesis of SFTSV and may be a useful target for antiviral interventions against the viral infection.

  2. The Ku Protein Complex Interacts with YY1, Is Up-Regulated in Human Heart Failure, and Represses α Myosin Heavy-Chain Gene Expression

    Science.gov (United States)

    Sucharov, Carmen C.; Helmke, Steve M.; Langer, Stephen J.; Perryman, M. Benjamin; Bristow, Michael; Leinwand, Leslie

    2004-01-01

    Human heart failure is accompanied by repression of genes such as α myosin heavy chain (αMyHC) and SERCA2A and the induction of fetal genes such as βMyHC and atrial natriuretic factor. It seems likely that changes in MyHC isoforms contribute to the poor contractility seen in heart failure, because small changes in isoform composition can have a major effect on the contractility of cardiac myocytes and the heart. Our laboratory has recently shown that YY1 protein levels are increased in human heart failure and that YY1 represses the activity of the human αMyHC promoter. We have now identified a region of the αMyHC promoter that binds a factor whose expression is increased sixfold in failing human hearts. Through peptide mass spectrometry, we identified this binding activity to be a heterodimer of Ku70 and Ku80. Expression of Ku represses the human αMyHC promoter in neonatal rat ventricular myocytes. Moreover, overexpression of Ku70/80 decreases αMyHC mRNA expression and increases skeletal α-actin. Interestingly, YY1 interacts with Ku70 and Ku80 in HeLa cells. Together, YY1, Ku70, and Ku80 repress the αMyHC promoter to an extent that is greater than that with YY1 or Ku70/80 alone. Our results suggest that Ku is an important factor in the repression of the human αMyHC promoter during heart failure. PMID:15367688

  3. Differential muscular myosin heavy chain expression of the pectoral and pelvic girdles during early growth in the king penguin (Aptenodytes patagonicus) chick.

    Science.gov (United States)

    Erbrech, Aude; Robin, Jean-Patrice; Guérin, Nathalie; Groscolas, René; Gilbert, Caroline; Martrette, Jean-Marc

    2011-06-01

    Continuous growth, associated with a steady parental food supply, is a general pattern in offspring development. So that young chicks can acquire their locomotor independence, this period is usually marked by a fast maturation of muscles, during which different myosin heavy chain (MyHC) isoforms are expressed. However, parental food provisioning may fluctuate seasonally, and offspring therefore face a challenge to ensure the necessary maturation of their tissues when energy is limited. To address this trade-off we investigated muscle maturation in both the pectoral and pelvic girdles of king penguin chicks. This species has an exceptionally long rearing period (1 year), which is prolonged when parental food provisioning is drastically reduced during the sub-Antarctic winter. Approximately 1 month post hatching, chicks acquire a functional pedestrian locomotion, which uses pelvic muscles, whereas swimming, which uses the pectoral muscles, only occurs 1 year later. We therefore tested the hypothesis that the MyHC content of the leg muscles reaches a mature state before those of the pectoral muscles. We found that leg muscle MyHC composition changed with the progressive acquisition of pedestrian locomotion, whereas pectoral muscle fibres reached their mature MyHC profile as early as hatching. Contrary to our predictions, the acquisition of the adult profile in pectoral muscles could be related to an early maturation of the contractile muscular proteins, presumably associated with early thermoregulatory capacities of chicks, necessary for survival in their cold environment. This differential maturation appears to reconcile both the locomotor and environmental constraints of king penguin chicks during growth.

  4. A mutation in the dynein heavy chain gene compensates for energy deficit of mutant SOD1 mice and increases potentially neuroprotective IGF-1

    Directory of Open Access Journals (Sweden)

    Larmet Yves

    2011-04-01

    Full Text Available Abstract Background Amyotrophic lateral sclerosis (ALS is a fatal neurodegenerative disease characterized by a progressive loss of motor neurons. ALS patients, as well as animal models such as mice overexpressing mutant SOD1s, are characterized by increased energy expenditure. In mice, this hypermetabolism leads to energy deficit and precipitates motor neuron degeneration. Recent studies have shown that mutations in the gene encoding the dynein heavy chain protein are able to extend lifespan of mutant SOD1 mice. It remains unknown whether the protection offered by these dynein mutations relies on a compensation of energy metabolism defects. Results SOD1(G93A mice were crossbred with mice harboring the dynein mutant Cramping allele (Cra/+ mice. Dynein mutation increased adipose stores in compound transgenic mice through increasing carbohydrate oxidation and sparing lipids. Metabolic changes that occurred in double transgenic mice were accompanied by the normalization of the expression of key mRNAs in the white adipose tissue and liver. Furthermore, Dynein Cra mutation rescued decreased post-prandial plasma triglycerides and decreased non esterified fatty acids upon fasting. In SOD1(G93A mice, the dynein Cra mutation led to increased expression of IGF-1 in the liver, increased systemic IGF-1 and, most importantly, to increased spinal IGF-1 levels that are potentially neuroprotective. Conclusions These findings suggest that the protection against SOD1(G93A offered by the Cramping mutation in the dynein gene is, at least partially, mediated by a reversal in energy deficit and increased IGF-1 availability to motor neurons.

  5. Contractile properties of motor units and expression of myosin heavy chain isoforms in rat fast-type muscle after volitional weight-lifting training.

    Science.gov (United States)

    Łochyński, Dawid; Kaczmarek, Dominik; Mrówczyński, Włodzimierz; Warchoł, Wojciech; Majerczak, Joanna; Karasiński, Janusz; Korostyński, Michał; Zoladz, Jerzy A; Celichowski, Jan

    2016-10-01

    Dynamic resistance training increases the force and speed of muscle contraction, but little is known about modifications to the contractile properties of the main physiological types of motor units (MUs) that contribute to these muscle adaptations. Although the contractile profile of MU muscle fibers is tightly coupled to myosin heavy chain (MyHC) protein expression, it is not well understood if MyHC transition is a prerequisite for modifications to the contractile characteristics of MUs. In this study, we examined MU contractile properties, the mRNA expression of MyHC, parvalbumin, and sarcoendoplasmic reticulum Ca 2+ pump isoforms, as well as the MyHC protein content after 5 wk of volitional progressive weight-lifting training in the medial gastrocnemius muscle in rats. The training had no effect on MyHC profiling or Ca 2+ -handling protein gene expression. Maximum force increased in slow (by 49%) and fast (by 21%) MUs. Within fast MUs, the maximum force increased in most fatigue-resistant and intermediate but not most fatigable MUs. Twitch contraction time was shortened in slow and fast fatigue-resistant MUs. Twitch half-relaxation was shortened in fast most fatigue-resistant and intermediate MUs. The force-frequency curve shifted rightward in fast fatigue-resistant MUs. Fast fatigable MUs fatigued less within the initial 15 s while fast fatigue-resistant units increased the ability to potentiate the force within the first minute of the standard fatigue test. In conclusion, at the early stage of resistance training, modifications to the contractile characteristics of MUs appear in the absence of MyHC transition and the upregulation of Ca 2+ -handling genes. Copyright © 2016 the American Physiological Society.

  6. Effective myotube formation in human adipose tissue-derived stem cells expressing dystrophin and myosin heavy chain by cellular fusion with mouse C2C12 myoblasts

    Energy Technology Data Exchange (ETDEWEB)

    Eom, Young Woo [Cell Therapy and Tissue Engineering Center, Wonju College of Medicine, Yonsei Univ., Wonju (Korea, Republic of); Biomedical Research Institute, Lifeliver Co., Ltd., Suwon (Korea, Republic of); Lee, Jong Eun; Yang, Mal Sook; Jang, In Keun; Kim, Hyo Eun; Lee, Doo Hoon; Kim, Young Jin [Biomedical Research Institute, Lifeliver Co., Ltd., Suwon (Korea, Republic of); Park, Won Jin [Dr. Park' s Aesthetic Clinic, Seoul (Korea, Republic of); Kong, Jee Hyun; Shim, Kwang Yong [Department of Hematology-Oncology, Wonju College of Medicine, Yonsei Univ., Wonju (Korea, Republic of); Lee, Jong In, E-mail: oncochem@yonsei.ac.kr [Department of Hematology-Oncology, Wonju College of Medicine, Yonsei Univ., Wonju (Korea, Republic of); Kim, Hyun Soo, E-mail: khsmd@unitel.co.kr [Department of Hematology-Oncology, Wonju College of Medicine, Yonsei Univ., Wonju (Korea, Republic of)

    2011-04-29

    Highlights: {yields} hASCs were differentiated into skeletal muscle cells by treatment with 5-azacytidine, FGF-2, and the supernatant of cultured hASCs. {yields} Dystrophin and MyHC were expressed in late differentiation step by treatment with the supernatant of cultured hASCs. {yields} hASCs expressing dystrophin and MyHC contributed to myotube formation during co-culture with mouse myoblast C2C12 cells. -- Abstract: Stem cell therapy for muscular dystrophies requires stem cells that are able to participate in the formation of new muscle fibers. However, the differentiation steps that are the most critical for this process are not clear. We investigated the myogenic phases of human adipose tissue-derived stem cells (hASCs) step by step and the capability of myotube formation according to the differentiation phase by cellular fusion with mouse myoblast C2C12 cells. In hASCs treated with 5-azacytidine and fibroblast growth factor-2 (FGF-2) for 1 day, the early differentiation step to express MyoD and myogenin was induced by FGF-2 treatment for 6 days. Dystrophin and myosin heavy chain (MyHC) expression was induced by hASC conditioned medium in the late differentiation step. Myotubes were observed only in hASCs undergoing the late differentiation step by cellular fusion with C2C12 cells. In contrast, hASCs that were normal or in the early stage were not involved in myotube formation. Our results indicate that stem cells expressing dystrophin and MyHC are more suitable for myotube formation by co-culture with myoblasts than normal or early differentiated stem cells expressing MyoD and myogenin.

  7. Effect of 48-h food deprivation on the expressions of myosin heavy-chain isoforms and fiber type-related factors in rats.

    Science.gov (United States)

    Mizunoya, Wataru; Sawano, Shoko; Iwamoto, Yohei; Sato, Yusuke; Tatsumi, Ryuichi; Ikeuchi, Yoshihide

    2013-01-01

    The primary aim of this study was to examine the effects of 48-h food deprivation on rat skeletal muscle fiber type, according to myosin heavy-chain (MyHC) isoform composition and some metabolism-related factors in both slow-type dominant and fast-type dominant muscle tissues. Male Wistar rats (7 wk old) were treated with 48-h food deprivation or ad libitum feeding as control. After the treatment, the soleus muscle (slow-type dominant) and the extensor digitorum longus (EDL, fast-type dominant) were excised. We found that 48-h food deprivation did not affect MyHC composition in either the soleus or EDL, compared with fed rats by electrophoretic separation of MyHC isoforms. However, 48-h food deprivation significantly increased the mRNA expression of fast-type MyHC2B in the EDL muscle. Moreover, food deprivation increased fatty acid metabolism, as shown by elevated levels of related serum energy substrates and mRNA expression of mitochondrial uncoupling protein (UCP) 3 and lipoprotein lipase (LPL) in both the soleus and EDL. UCP3 and LPL are generally expressed at higher levels in slow-type fibers. Furthermore, we found that food deprivation significantly decreased the protein amounts of PGC1α and phosphorylated FOXO1, which are known as skeletal muscle fiber type regulators. In conclusion, 48-h food deprivation increased mRNA expression of fast-type MyHC isoform and oxidative metabolism-related factors in EDL, whereas MyHC composition at the protein level did not change in either the soleus or EDL.

  8. Effects of membrane properties on the binding activities of the HN and HC heavy-chain domains of botulinum neurotoxin A.

    Science.gov (United States)

    Ayyar, B Vijayalakshmi; Atassi, M Zouhair

    2016-12-01

    Binding behaviors of the H N and the H C domains of BoNT/A were investigated individually to identify if there exist any differences in their interaction with the cell membrane. Recombinant fragments corresponding to both BoNT/A H N and H C regions were prepared (H N 519-845 and H C 967-1296) and their binding to synaptic proteins was verified. The binding behaviors of these heavy-chain domains were analyzed by treating the Neuro 2a, a murine neuroblastoma cell line, with compounds known to alter membrane properties. Cholesterol depletion and lipid raft inhibition increased the binding of H N 519-845 to Neuro 2a cells without affecting H C 967-1296-cell interaction. Sphingolipid depletion decreased the binding of cells to both H C 967-1296 and H N 519-845 whereas, loading exogenous GD1a, on to the Neuro 2a cells, increased the binding of both the peptides to cells. Microtubule disruption of the Neuro 2a cells by nocodazole decreased the binding of both H C 967-1296 and H N 519-845 to the treated cells. Inhibition of the clathrin-mediated endocytosis using dynasore, chlorpromazine or potassium (K + ) depletion buffer lowered the binding of both H C 967-1296 and H N 519-845 to the cells, but seemed to exert a more pronounced effect on the binding of H C 967-1296 than on the binding of H N 519-845. Results indicate that while both the H N and H C domains are involved in the binding of the toxin to neuronal cells there are differences in their behavior which probably stem from their respective amino acid composition and structural location in the toxin three-dimensional structure along with their intended role in translocation and internalization into the cells. Copyright © 2016 Elsevier B.V. All rights reserved.

  9. Influence of injection of Chinese botulinum toxin type A on the histomorphology and myosin heavy chain composition of rat gastrocnemius muscles.

    Science.gov (United States)

    Hong, Bin; Chen, Min; Hu, Xing-yue

    2013-11-01

    Botulinum toxin type A (BoNT/A) is a metalloprotease that blocks synaptic transmission via the cleavage of a synaptosomal-associated protein of 25 kDa (SNAP-25). It has gained widespread use as a treatment for cerebral palsy and skeletal muscle hypertrophy. In China, Chinese botulinum toxin type A (CBTX-A), a type of BoNT/A, is in widespread clinical use. However, the changes in the morphological and biochemical properties of treated muscles and in remote muscles from the CBTX-A injection site are relatively unknown. Therefore, we investigated the changes in histomorphology and myosin heavy chain (MyHC) isoform composition and distribution in rat gastrocnemius muscles after intramuscular injection of CBTX-A. The weakness of the injected muscles was assessed periodically to identify their functional deficiency. Muscle slices were stained with hematoxylin-eosin (HE) and adenosine triphosphatase (ATPase). MyHC isoform composition was analyzed by sodium dodecyl sulfate-polyacrylamide gel electrophoresis (SDS-PAGE) to uncover changes in morphological and biochemical properties. Our findings demonstrate that following injection of CBTX-A 5 U into rat gastrocnemius muscles, shifts in MyHC isoform composition emerged on the third day after injection and peaked in the fourth week. The composition remained distinctly different from that of the control group after the twelfth week. More specifically, there was a decrease in the proportion of the type IIb isoform and an increase in the proportions of type IIx, type IIa, and type I isoforms. Data revealed that CBTX-A led to a shift in MyHC composition towards slower isoforms and that the MyHC composition remained far from normal six months after a single injection. However, no noticeable remote muscle weakness was induced.

  10. Effective myotube formation in human adipose tissue-derived stem cells expressing dystrophin and myosin heavy chain by cellular fusion with mouse C2C12 myoblasts

    International Nuclear Information System (INIS)

    Eom, Young Woo; Lee, Jong Eun; Yang, Mal Sook; Jang, In Keun; Kim, Hyo Eun; Lee, Doo Hoon; Kim, Young Jin; Park, Won Jin; Kong, Jee Hyun; Shim, Kwang Yong; Lee, Jong In; Kim, Hyun Soo

    2011-01-01

    Highlights: → hASCs were differentiated into skeletal muscle cells by treatment with 5-azacytidine, FGF-2, and the supernatant of cultured hASCs. → Dystrophin and MyHC were expressed in late differentiation step by treatment with the supernatant of cultured hASCs. → hASCs expressing dystrophin and MyHC contributed to myotube formation during co-culture with mouse myoblast C2C12 cells. -- Abstract: Stem cell therapy for muscular dystrophies requires stem cells that are able to participate in the formation of new muscle fibers. However, the differentiation steps that are the most critical for this process are not clear. We investigated the myogenic phases of human adipose tissue-derived stem cells (hASCs) step by step and the capability of myotube formation according to the differentiation phase by cellular fusion with mouse myoblast C2C12 cells. In hASCs treated with 5-azacytidine and fibroblast growth factor-2 (FGF-2) for 1 day, the early differentiation step to express MyoD and myogenin was induced by FGF-2 treatment for 6 days. Dystrophin and myosin heavy chain (MyHC) expression was induced by hASC conditioned medium in the late differentiation step. Myotubes were observed only in hASCs undergoing the late differentiation step by cellular fusion with C2C12 cells. In contrast, hASCs that were normal or in the early stage were not involved in myotube formation. Our results indicate that stem cells expressing dystrophin and MyHC are more suitable for myotube formation by co-culture with myoblasts than normal or early differentiated stem cells expressing MyoD and myogenin.

  11. Enhancement of MHC-I antigen presentation via architectural control of pH-responsive, endosomolytic polymer nanoparticles.

    Science.gov (United States)

    Wilson, John T; Postma, Almar; Keller, Salka; Convertine, Anthony J; Moad, Graeme; Rizzardo, Ezio; Meagher, Laurence; Chiefari, John; Stayton, Patrick S

    2015-03-01

    Protein-based vaccines offer a number of important advantages over organism-based vaccines but generally elicit poor CD8(+) T cell responses. We have previously demonstrated that pH-responsive, endosomolytic polymers can enhance protein antigen delivery to major histocompatibility complex class I (MHC-I) antigen presentation pathways thereby augmenting CD8(+) T cell responses following immunization. Here, we describe a new family of nanocarriers for protein antigen delivery assembled using architecturally distinct pH-responsive polymers. Reversible addition-fragmentation chain transfer (RAFT) polymerization was used to synthesize linear, hyperbranched, and core-crosslinked copolymers of 2-(N,N-diethylamino)ethyl methacrylate (DEAEMA) and butyl methacrylate (BMA) that were subsequently chain extended with a hydrophilic N,N-dimethylacrylamide (DMA) segment copolymerized with thiol-reactive pyridyl disulfide (PDS) groups. In aqueous solution, polymer chains assembled into 25 nm micellar nanoparticles and enabled efficient and reducible conjugation of a thiolated protein antigen, ovalbumin. Polymers demonstrated pH-dependent membrane-destabilizing activity in an erythrocyte lysis assay, with the hyperbranched and cross-linked polymer architectures exhibiting significantly higher hemolysis at pH ≤ 7.0 than the linear diblock. Antigen delivery with the hyperbranched and cross-linked polymer architecture enhanced in vitro MHC-I antigen presentation relative to free antigen, whereas the linear construct did not have a discernible effect. The hyperbranched system elicited a four- to fivefold increase in MHC-I presentation relative to the cross-linked architecture, demonstrating the superior capacity of the hyperbranched architecture in enhancing MHC-I presentation. This work demonstrates that the architecture of pH-responsive, endosomolytic polymers can have dramatic effects on intracellular antigen delivery, and offers a promising strategy for enhancing CD8(+) T cell

  12. CD4+ T cell-mediated rejection of MHC class II-positive tumor cells is dependent on antigen secretion and indirect presentation on host APCs.

    Science.gov (United States)

    Haabeth, Ole Audun Werner; Fauskanger, Marte; Manzke, Melanie; Lundin, Katrin U; Corthay, Alexandre; Bogen, Bjarne; Tveita, Anders Aune

    2018-05-11

    Tumor-specific CD4+ T cells have been shown to mediate efficient anti-tumor immune responses against cancer. Such responses can occur through direct binding to MHC class II (MHC II)-expressing tumor cells or indirectly via activation of professional antigen-presenting cells (APC) that take up and present the tumor antigen. We have previously shown that CD4+ T cells reactive against an epitope within the Ig light chain variable region of a murine B cell lymphoma can reject established tumors. Given the presence of MHC II molecules at the surface of lymphoma cells, we investigated whether MHC II-restricted antigen presentation on tumor cells alone was required for rejection. Variants of the A20 B lymphoma cell line that either secreted or intracellularly retained different versions of the tumor-specific antigen revealed that antigen secretion by the MHC II-expressing tumor cells was essential both for the priming and effector phase of CD4+ T cell-driven anti-tumor immune responses. Consistent with this, genetic ablation of MHC II in tumor cells, both in the case of B lymphoma and B16 melanoma, did not preclude rejection of tumors by tumor antigen-specific CD4+ T cells in vivo. These findings demonstrate that MHC class II expression on tumor cells themselves is not required for CD4+ T cell-mediated rejection, and that indirect display on host APC is sufficient for effective tumor elimination. These results support the importance of tumor-infiltrating APC as mediators of tumor cell killing by CD4+ T cells. Copyright ©2018, American Association for Cancer Research.

  13. Complex Mhc-based mate choice in a wild passerine

    Science.gov (United States)

    Bonneaud, Camille; Chastel, Olivier; Federici, Pierre; Westerdahl, Helena; Sorci, Gabriele

    2006-01-01

    The extreme polymorphism of the vertebrate major histocompatibility complex (Mhc) is famous for protecting hosts against constantly evolving pathogens. Mate choice is often evoked as a means of maintaining Mhc variability through avoidance of partners with similar Mhc alleles or preference for heterozygotes. Evidence for these two hypotheses mostly comes from studies on humans and laboratory mice. Here, we tested these hypotheses in a wild outbred population of house sparrows (Passer domesticus). Females were not more or less closely related to the males they paired with when considering neutral genetic variation. However, males failed to form breeding pairs when they had too few Mhc alleles and when they were too dissimilar from females at Mhc loci (i.e. had no common alleles). Furthermore, pairs did not form at random as Mhc diversity positively correlated in mating pairs. These results suggest that mate choice evolves in response to (i) benefits in terms of parasite resistance acquired from allelic diversity, and (ii) costs associated with the disruption of co-adapted genes. PMID:16600889

  14. MHC class II polymorphisms, autoreactive T-cells and autoimmunity

    Directory of Open Access Journals (Sweden)

    Sue eTsai

    2013-10-01

    Full Text Available Major histocompatibility complex (MHC genes, also known as human leukocyte antigen genes (HLA in humans, are the prevailing contributors of genetic susceptibility to autoimmune diseases such as Type 1 Diabetes (T1D, Multiple Sclerosis (MS, and Rheumatoid arthritis (RA, among others (Todd and Wicker, 2001;MacKay et al., 2002;Hafler et al., 2007. Although the pathways through which MHC molecules afford autoimmune risk or resistance remain to be fully mapped out, it is generally accepted that they do so by shaping the central and peripheral T cell repertoires of the host towards autoimmune proclivity or resistance, respectively. Disease-predisposing MHC alleles would both spare autoreactive thymocytes from central tolerance and bias their development towards a pathogenic phenotype. Protective MHC alleles, on the other hand, would promote central deletion of autoreactive thymocytes and skew their development towards non-pathogenic phenotypes. This interpretation of the data is at odds with two other observations: that in MHC-heterozygous individuals, resistance is dominant over susceptibility; and that it is difficult to understand how deletion of one or a few clonal autoreactive T cell types would suffice to curb autoimmune responses driven by hundreds if not thousands of autoreactive T cell specificities. This review provides an update on current advances in our understanding of the mechanisms underlying MHC class II-associated autoimmune disease susceptibility and/or resistance and attempts to reconcile these seemingly opposing concepts.

  15. Inter-alpha-trypsin inhibitor heavy chain 4: a novel biomarker for environmental exposure to particulate air pollution in patients with chronic obstructive pulmonary disease

    Directory of Open Access Journals (Sweden)

    Lee KY

    2015-04-01

    Full Text Available Kang-Yun Lee,1–3 Po-Hao Feng,1,2 Shu-Chuan Ho,4 Kai-Jen Chuang,5,6 Tzu-Tao Chen,2,3 Chien-Ling Su,2,4 Wen-Te Liu,2,4 Hsiao-Chi Chuang2,4 1Department of Internal Medicine, School of Medicine, College of Medicine, Taipei Medical University, 2Division of Pulmonary Medicine, Department of Internal Medicine, Shuang Ho Hospital, Taipei Medical University, 3Graduate Institute of Clinical Medicine, College of Medicine, Taipei Medical University, 4School of Respiratory Therapy, College of Medicine, Taipei Medical University, 5Department of Public Health, School of Medicine, College of Medicine, Taipei Medical University, 6School of Public Health, College of Public Health and Nutrition, Taipei Medical University, Taipei, Taiwan Abstract: Chronic obstructive pulmonary disease (COPD is a chronic inflammatory disease that is correlated with environmental stress. Particulate matter ≤10 µm (PM10 is considered to be a risk factor for COPD development; however, the effects of PM10 on the protein levels in COPD remain unclear. Fifty subjects with COPD and 15 healthy controls were recruited. Gene ontology analysis of differentially expressed proteins identified immune system process and binding as the most important biological process and molecular function, respectively, in the responses of PM10-exposed patients with COPD. Biomarkers for PM10 in COPD were identified and compared with the same in healthy controls and included proteoglycan 4 (PRG4, inter-alpha-trypsin inhibitor heavy chain 4 (ITIH4, and apolipoprotein F (APOF. PRG4 and ITIH4 were associated with a past 3-year PM10 exposure level. The receiver operating characteristic curve analysis showed that ITIH4 is a sensitive and specific biomarker for PM10 exposure (area under the curve [AUC] =0.690, P=0.015 compared with PRG4 (AUC =0.636, P=0.083, APOF (AUC =0.523, P=0.766, 8-isoprostane (AUC =0.563, P=0.405, and C-reactive protein (CRP; AUC =0.634, P=0.086. ITIH4 levels were correlated with CRP (r=0

  16. Immunogenicity and Protective Efficacy of Brugia malayi Heavy Chain Myosin as Homologous DNA, Protein and Heterologous DNA/Protein Prime Boost Vaccine in Rodent Model.

    Directory of Open Access Journals (Sweden)

    Jyoti Gupta

    Full Text Available We earlier demonstrated the immunoprophylactic efficacy of recombinant heavy chain myosin (Bm-Myo of Brugia malayi (B. malayi in rodent models. In the current study, further attempts have been made to improve this efficacy by employing alternate approaches such as homologous DNA (pcD-Myo and heterologous DNA/protein prime boost (pcD-Myo+Bm-Myo in BALB/c mouse model. The gene bm-myo was cloned in a mammalian expression vector pcDNA 3.1(+ and protein expression was confirmed in mammalian Vero cell line. A significant degree of protection (79.2%±2.32 against L3 challenge in pcD-Myo+Bm-Myo immunized group was observed which was much higher than that exerted by Bm-Myo (66.6%±2.23 and pcD-Myo (41.6%±2.45. In the heterologous immunized group, the percentage of peritoneal leukocytes such as macrophages, neutrophils, B cells and T cells marginally increased and their population augmented further significantly following L3 challenge. pcD-Myo+Bm-Myo immunization elicited robust cellular and humoral immune responses as compared to pcD-Myo and Bm-Myo groups as evidenced by an increased accumulation of CD4+, CD8+ T cells and CD19+ B cells in the mouse spleen and activation of peritoneal macrophages. Though immunized animals produced antigen-specific IgG antibodies and isotypes, sera of mice receiving pcD-Myo+Bm-Myo or Bm-Myo developed much higher antibody levels than other groups and there was profound antibody-dependent cellular adhesion and cytotoxicity (ADCC to B. malayi infective larvae (L3. pcD-Myo+Bm-Myo as well as Bm-Myo mice generated a mixed T helper cell phenotype as evidenced by the production of both pro-inflammatory (IL-2, IFN-γ and anti-inflammatory (IL-4, IL-10 cytokines. Mice receiving pcD-Myo on contrary displayed a polarized pro-inflammatory immune response. The findings suggest that the priming of animals with DNA followed by protein booster generates heightened and mixed pro- and anti-inflammatory immune responses that are capable of

  17. Effect of pedaling rates and myosin heavy chain composition in the vastus lateralis muscle on the power generating capability during incremental cycling in humans.

    Science.gov (United States)

    Majerczak, J; Szkutnik, Z; Duda, K; Komorowska, M; Kolodziejski, L; Karasinski, J; Zoladz, J A

    2008-01-01

    In this study, we have determined power output reached at maximal oxygen uptake during incremental cycling exercise (P(I, max)) performed at low and at high pedaling rates in nineteen untrained men with various myosin heavy chain composition (MyHC) in the vastus lateralis muscle. On separate days, subjects performed two incremental exercise tests until exhaustion at 60 rev min(-1) and at 120 rev min(-1). In the studied group of subjects P(I, max) reached during cycling at 60 rev min(-1) was significantly higher (p=0.0001) than that at 120 rev min(-1) (287+/-29 vs. 215+/-42 W, respectively for 60 and 120 rev min(-1)). For further comparisons, two groups of subjects (n=6, each) were selected according to MyHC composition in the vastus lateralis muscle: group H with higher MyHC II content (56.8+/-2.79 %) and group L with lower MyHC II content in this muscle (28.6+/-5.8 %). P(I, max) reached during cycling performed at 60 rev min(-1) in group H was significantly lower than in group L (p=0.03). However, during cycling at 120 rev min(-1), there was no significant difference in P(I, max) reached by both groups of subjects (p=0.38). Moreover, oxygen uptake (VO(2)), blood hydrogen ion [H(+)], plasma lactate [La(-)] and ammonia [NH(3)] concentrations determined at the four highest power outputs completed during the incremental cycling performed at 60 as well as 120 rev min(-1), in the group H were significantly higher than in group L. We have concluded that during an incremental exercise performed at low pedaling rates the subjects with lower content of MyHC II in the vastus lateralis muscle possess greater power generating capabilities than the subjects with higher content of MyHC II. Surprisingly, at high pedaling rate, power generating capabilities in the subjects with higher MyHC II content in the vastus lateralis muscle did not differ from those found in the subjects with lower content of MyHC II in this muscle, despite higher blood [H(+)], [La(-)] and [NH(3

  18. Contrasting patterns of selection between MHC I and II across populations of Humboldt and Magellanic penguins.

    Science.gov (United States)

    Sallaberry-Pincheira, Nicole; González-Acuña, Daniel; Padilla, Pamela; Dantas, Gisele P M; Luna-Jorquera, Guillermo; Frere, Esteban; Valdés-Velásquez, Armando; Vianna, Juliana A

    2016-10-01

    The evolutionary and adaptive potential of populations or species facing an emerging infectious disease depends on their genetic diversity in genes, such as the major histocompatibility complex (MHC). In birds, MHC class I deals predominantly with intracellular infections (e.g., viruses) and MHC class II with extracellular infections (e.g., bacteria). Therefore, patterns of MHC I and II diversity may differ between species and across populations of species depending on the relative effect of local and global environmental selective pressures, genetic drift, and gene flow. We hypothesize that high gene flow among populations of Humboldt and Magellanic penguins limits local adaptation in MHC I and MHC II, and signatures of selection differ between markers, locations, and species. We evaluated the MHC I and II diversity using 454 next-generation sequencing of 100 Humboldt and 75 Magellanic penguins from seven different breeding colonies. Higher genetic diversity was observed in MHC I than MHC II for both species, explained by more than one MHC I loci identified. Large population sizes, high gene flow, and/or similar selection pressures maintain diversity but limit local adaptation in MHC I. A pattern of isolation by distance was observed for MHC II for Humboldt penguin suggesting local adaptation, mainly on the northernmost studied locality. Furthermore, trans-species alleles were found due to a recent speciation for the genus or convergent evolution. High MHC I and MHC II gene diversity described is extremely advantageous for the long-term survival of the species.

  19. Sex-specific selection for MHC variability in Alpine chamois

    Directory of Open Access Journals (Sweden)

    Schaschl Helmut

    2012-02-01

    Full Text Available Abstract Background In mammals, males typically have shorter lives than females. This difference is thought to be due to behavioural traits which enhance competitive abilities, and hence male reproductive success, but impair survival. Furthermore, in many species males usually show higher parasite burden than females. Consequently, the intensity of selection for genetic factors which reduce susceptibility to pathogens may differ between sexes. High variability at the major histocompatibility complex (MHC genes is believed to be advantageous for detecting and combating the range of infectious agents present in the environment. Increased heterozygosity at these immune genes is expected to be important for individual longevity. However, whether males in natural populations benefit more from MHC heterozygosity than females has rarely been investigated. We investigated this question in a long-term study of free-living Alpine chamois (Rupicapra rupicapra, a polygynous mountain ungulate. Results Here we show that male chamois survive significantly (P = 0.022 longer if heterozygous at the MHC class II DRB locus, whereas females do not. Improved survival of males was not a result of heterozygote advantage per se, as background heterozygosity (estimated across twelve microsatellite loci did not change significantly with age. Furthermore, reproductively active males depleted their body fat reserves earlier than females leading to significantly impaired survival rates in this sex (P Conclusions Increased MHC class II DRB heterozygosity with age in males, suggests that MHC heterozygous males survive longer than homozygotes. Reproductively active males appear to be less likely to survive than females most likely because of the energetic challenge of the winter rut, accompanied by earlier depletion of their body fat stores, and a generally higher parasite burden. This scenario renders the MHC-mediated immune response more important for males than for females

  20. COAXIAL DISK SHUNT FOR MEASURING IN THE HEAVY-CURRENT CHAIN OF HIGH-VOLTAGE GENERATOR OF STORM DISCHARGES OF IMPULSES OF CURRENT OF ARTIFICIAL LIGHTNING WITH THE INTEGRAL OF ACTION TO 15•106 J/OHM

    Directory of Open Access Journals (Sweden)

    M. I. Baranov

    2017-10-01

    Full Text Available Purpose. Description of construction and basic technical descriptions developed and created in Research & Design Institute «Molniya» National Technical University «Kharkiv Polytechnic Institute» high-voltage heavy-current coaxial disk shunt of type of SC-300M2, allowing reliably to measure the peak-temporal parameters (PTP of impulses of current of artificial lightning in wide peak and temporal ranges with the integral of their action to 15·106 J/Ohm. Methodology. Electrophysics bases of high-voltage impulsive technique, scientific and technical bases of development and creation of high-voltage heavy-current impulsive electrical equipment, including the powerful generators of current of lightning (GCL, and also measuring methods in bit chains powerful high-voltage GCL AVP large impulsive currents of micro- and millisecond temporal ranges. Results. Offered and described new construction of measuring high-voltage heavy-current shunt, containing a measuring round disk from stainless steel easily soiled a 12Х18Н10Т thickness 2 mm and external diameter 80 mm. Experimental a way impulsive active resistance of RS≈0,08 mOhm of the indicated measuring disk and on his basis a calculation coefficient transformation is found of SS of coaxial disk shunt of type of SC-300M2, numeral equal in the concerted mode of operations of his coaxial cable line (CCL SS≈2/RS≈25·103 A/V. It is rotined that it is expedient to use this value SS for measuring in the heavy-current bit chain of GCL ATP impulsive A- and repeated impulsive D- component of current of artificial lightning, and also ATP of aperiodic impulse of current of artificial lightning of temporal form 10 μc/350 μc. It is set that taking into account application in the end CCL of shunt of a co-ordinate divizor of voltage with two output coaxial sockets 1:1 (for SSA≈25·103 A/V and 1:2 (SSC≈12,5·103 A/V at measuring of ATP intermediate B-, protracted C- and shortened protracted C

  1. NLRC5: a key regulator of MHC class I-dependent immune responses.

    Science.gov (United States)

    Kobayashi, Koichi S; van den Elsen, Peter J

    2012-12-01

    The expression of MHC class I molecules is crucial for the initiation and regulation of adaptive immune responses against pathogens. NOD-, LRR- and CARD-containing 5 (NLRC5) was recently identified as a specific transactivator of MHC class I genes (CITA). NLRC5 and the master regulator for MHC class II genes, class II transactivator (CIITA), interact with similar MHC promoter-bound factors. Here, we provide a broad overview of the molecular mechanisms behind MHC class I transcription and the role of the class I transactivator NLRC5 in MHC class I-dependent immune responses.

  2. Understanding TR binding to pMHC complexes: how does a TR scan many pMHC complexes yet preferentially bind to one.

    Directory of Open Access Journals (Sweden)

    Javed Mohammed Khan

    Full Text Available Understanding the basis of the binding of a T cell receptor (TR to the peptide-MHC (pMHC complex is essential due to the vital role it plays in adaptive immune response. We describe the use of computed binding (free energy (BE, TR paratope, pMHC epitope, molecular surface electrostatic potential (MSEP and calculated TR docking angle (θ to analyse 61 TR/pMHC crystallographic structures to comprehend TR/pMHC interaction. In doing so, we have successfully demonstrated a novel/rational approach for θ calculation, obtained a linear correlation between BE and θ without any "codon" or amino acid preference, provided an explanation for TR ability to scan many pMHC ligands yet specifically bind one, proposed a mechanism for pMHC recognition by TR leading to T cell activation and illustrated the importance of the peptide in determining TR specificity, challenging the "germline bias" theory.

  3. Real Time RT-PCR with a Newly Designed Set of Promers Confirmed the Presence of 2b and 2x/d Myosim Heavy Chain mRNAs in the Rat Slow Soleus Muscle

    Czech Academy of Sciences Publication Activity Database

    Žurmanová, Jitka; Půta, F.; Stopková, R.; Soukup, Tomáš

    2008-01-01

    Roč. 57, č. 6 (2008), s. 973-978 ISSN 0862-8408 R&D Projects: GA MŠk(CZ) LC554; GA ČR(CZ) GA305/06/1115; GA ČR(CZ) GA304/08/0256 Grant - others:EC(XE) LSH-CT-2004-511978 Institutional research plan: CEZ:AV0Z50110509 Keywords : rat slow soleus muscle * myosin heavy chain isoforms * real time RT-PCR Subject RIV: ED - Physiology Impact factor: 1.653, year: 2008

  4. Levels of myosin heavy chain mRNA transcripts and content of protein isoforms in the slow soleus muscle of 7 month-old rats with altered thyroid status

    Czech Academy of Sciences Publication Activity Database

    Vadászová, Adriana; Hudecová, S.; Križanová, O.; Soukup, Tomáš

    2006-01-01

    Roč. 55, č. 2 (2006), s. 221-225 ISSN 0862-8408 R&D Projects: GA ČR(CZ) GD305/03/H148; GA ČR(CZ) GA304/05/0327 Grant - others:VEGA(SK) 2/6078; SAV(SK) APVT-51-027404; NATO(XE) 979876; MYORES(XE) 511978 Institutional research plan: CEZ:AV0Z50110509 Keywords : myosin heavy chain * thyroid hormones status * mRNA transcripts Subject RIV: ED - Physiology Impact factor: 2.093, year: 2006

  5. Genetic variation of the major histocompatibility complex (MHC class II B gene in the threatened Hume's pheasant, Syrmaticus humiae.

    Directory of Open Access Journals (Sweden)

    Weicai Chen

    Full Text Available Major histocompatibility complex (MHC genes are the most polymorphic genes in vertebrates and encode molecules that play a crucial role in pathogen resistance. As a result of their diversity, they have received much attention in the fields of evolutionary and conservation biology. Here, we described the genetic variation of MHC class II B (MHCIIB exon 2 in a wild population of Hume's pheasant (Syrmaticus humiae, which has suffered a dramatic decline in population over the last three decades across its ranges in the face of heavy exploitation and habitat loss. Twenty-four distinct alleles were found in 73 S. humiae specimens. We found seven shared alleles among four geographical groups as well as six rare MHCIIB alleles. Most individuals displayed between one to five alleles, suggesting that there are at least three MHCIIB loci of the Hume's pheasant. The dN ⁄ dS ratio at putative antigen-binding sites (ABS was significantly greater than one, indicating balancing selection is acting on MHCIIB exon 2. Additionally, recombination and gene conversion contributed to generating MHCIIB diversity in the Hume's pheasant. One to three recombination events and seventy-five significant gene conversion events were observed within the Hume's pheasant MHCIIB loci. The phylogenetic tree and network analysis revealed that the Hume's pheasant alleles do not cluster together, but are scattered through the tree or network indicating a trans-species evolutionary mode. These findings revealed the evolution of the Hume's pheasant MHC after suffering extreme habitat fragmentation.

  6. Comparative genome analyses reveal distinct structure in the saltwater crocodile MHC.

    Directory of Open Access Journals (Sweden)

    Weerachai Jaratlerdsiri

    Full Text Available The major histocompatibility complex (MHC is a dynamic genome region with an essential role in the adaptive immunity of vertebrates, especially antigen presentation. The MHC is generally divided into subregions (classes I, II and III containing genes of similar function across species, but with different gene number and organisation. Crocodylia (crocodilians are widely distributed and represent an evolutionary distinct group among higher vertebrates, but the genomic organisation of MHC within this lineage has been largely unexplored. Here, we studied the MHC region of the saltwater crocodile (Crocodylus porosus and compared it with that of other taxa. We characterised genomic clusters encompassing MHC class I and class II genes in the saltwater crocodile based on sequencing of bacterial artificial chromosomes. Six gene clusters spanning ∼452 kb were identified to contain nine MHC class I genes, six MHC class II genes, three TAP genes, and a TRIM gene. These MHC class I and class II genes were in separate scaffold regions and were greater in length (2-6 times longer than their counterparts in well-studied fowl B loci, suggesting that the compaction of avian MHC occurred after the crocodilian-avian split. Comparative analyses between the saltwater crocodile MHC and that from the alligator and gharial showed large syntenic areas (>80% identity with similar gene order. Comparisons with other vertebrates showed that the saltwater crocodile had MHC class I genes located along with TAP, consistent with birds studied. Linkage between MHC class I and TRIM39 observed in the saltwater crocodile resembled MHC in eutherians compared, but absent in avian MHC, suggesting that the saltwater crocodile MHC appears to have gene organisation intermediate between these two lineages. These observations suggest that the structure of the saltwater crocodile MHC, and other crocodilians, can help determine the MHC that was present in the ancestors of archosaurs.

  7. Triticale (XTriticosecale W.) Heavy Metal Upptake as a Possibility of Food Chain Pollution in a Long-Term Field Experiment in Hungary

    Science.gov (United States)

    László Phd, M., ,, Dr.

    2009-04-01

    mixes and crackers due to a savory, nutty flavor. Etanol plants will pay a premium for triticale over barley since it has more starch and no hull, making alcohol production more efficient. Germany, France, China, Poland and Hungary account for nearly 90 percent of world triticale production (Donald et al. 2001). Heavy metals are dangerous because they tend to bioaccumulate in food chain. Bioaccumulation means an increase in the concentration of a chemical in a biological organism over time, compared to the chemical`s concentration in they environment. Compounds accumulate in living things any time they are taken up and stored faster han they are broken down (metabolize) or extreted. Crops have ability to heavy metal accumulation from fertilizers such as Cd, Pb, Cu, Zn etc. to a different degree (Lee et al. 2001, Scholz and Ellerbrock 2004). The main purposes of this study was to determine the triticale toxic element upptake by the soil, triticale leaf+straw and grain element concentrations on acid sandy soil in a long-term field fertilization experiment at Nyirlugos, Hungary in 1998. Material and Methods: Field experiments were carried out on an acidic sandy brown forest soil at Nyírlugos in East-Hungary from 1962 to 2005. Soil geochemical parameters were as follow: humus 0.6%, pH (H2O) 5.8, pH (KCl) 4.6, total N 32.8 mg/kg, AL (ammonium lactate soluble)- P2O5 43 mg/kg, AL-K2O 52 mg/kg. The experiments involved 32 NPKCaMg treatments in 4 replications giving a total of 128 plots. N levels were 0, 50, 100, 150 kg/ha/yr, P2O5 and K2O 0, 60, 120, 180 kg/ha/yr, CaCO3 0, 250, 500, 1000 kg/ha/yr and MgCO3 doses were 0, 140, 280 kg/ha/yr. Plot brutto size was 50 m2. Composite soil samples consisting of 25 subsamples collected at before flowering time from the ploughed layer of each plot. The so-called "mobile" fraction was extracted by ammonium-acetate+EDTA (AAc+EDTA, Lakanen and Ervio 1971) and the heavy metal determination by ICP-AES technic. Plant leaf+straw and seed

  8. Circumvention of MHC class II restriction by genetic immunization.

    Science.gov (United States)

    Schuler, K; Lu, C; Chang, H D; Croft, M; Zanetti, M; Gerloni, M

    2001-11-12

    The fate of T cell responses to peptide-based vaccination is subject to constraints by the major histocompatibility complex (MHC), MHC restriction. Using as a model system of T and B cell epitopes from the circumsporozoite protein of Plasmodium falciparum malaria parasite, we show that vaccination by somatic transgene immunization readily primes Balb/c mice (H-2(d)) a strain previously reported to be non-responder to immunization with a synthetic peptide vaccine encompassing these epitopes. Following genetic vaccination Balb/c mice developed a primary T cell response comparable to that of the responder strain C57Bl/6 (H-2(b)). Following booster immunization on day 45 Balb/c mice responded with a typical T cell memory response. Priming induced the formation of specific antibodies, which rose sharply after booster immunization. These findings suggests that genetic immunization can circumvent MHC class II restriction.

  9. Evolution of MHC class I in the Order Crocodylia

    DEFF Research Database (Denmark)

    Jaratlerdsiri, Weerachai; Isberg, Sally R; Higgins, Damien P

    2014-01-01

    have mostly focused on model species. However, the investigation of this region in non-avian reptiles is still in its infancy. To provide insights into the evolutionary mechanisms that have shaped the diversity of this region in the Order Crocodylia, we investigated MHC class I exon 3, intron 3...... events of gene duplication, particularly in Crocodilidae. These findings enhance our understanding of MHC class I evolution and provide a preliminary framework for comparative studies of other non-avian reptiles as well as diversity assessment within Crocodylia....

  10. Contrasting patterns of selection between MHC I and II across populations of Humboldt and Magellanic penguins

    OpenAIRE

    Sallaberry?Pincheira, Nicole; Gonz?lez?Acu?a, Daniel; Padilla, Pamela; Dantas, Gisele P. M.; Luna?Jorquera, Guillermo; Frere, Esteban; Vald?s?Vel?squez, Armando; Vianna, Juliana A.

    2016-01-01

    Abstract The evolutionary and adaptive potential of populations or species facing an emerging infectious disease depends on their genetic diversity in genes, such as the major histocompatibility complex (MHC). In birds, MHC class I deals predominantly with intracellular infections (e.g., viruses) and MHC class II with extracellular infections (e.g., bacteria). Therefore, patterns of MHC I and II diversity may differ between species and across populations of species depending on the relative e...

  11. Hotspots for Vitamin-Steroid-Thyroid Hormone Response Elements Within Switch Regions of Immunoglobulin Heavy Chain Loci Predict a Direct Influence of Vitamins and Hormones on B Cell Class Switch Recombination.

    Science.gov (United States)

    Hurwitz, Julia L; Penkert, Rhiannon R; Xu, Beisi; Fan, Yiping; Partridge, Janet F; Maul, Robert W; Gearhart, Patricia J

    2016-03-01

    Vitamin A deficiencies are common throughout the world and have a significant negative influence on immune protection against viral infections. Mouse models demonstrate that the production of IgA, a first line of defense against viruses at mucosal sites, is inhibited in the context of vitamin A deficiency. In vitro, the addition of vitamin A to activated B cells can enhance IgA expression, but downregulate IgE. Previous reports have demonstrated that vitamin A modifies cytokine patterns, and in so doing may influence antibody isotype expression by an indirect mechanism. However, we have now discovered hundreds of potential response elements among Sμ, Sɛ, and Sα switch sites within immunoglobulin heavy chain loci. These hotspots appear in both mouse and human loci and include targets for vitamin receptors and related proteins (e.g., estrogen receptors) in the nuclear receptor superfamily. Full response elements with direct repeats are relatively infrequent or absent in Sγ regions although half-sites are present. Based on these results, we pose a hypothesis that nuclear receptors have a direct effect on the immunoglobulin heavy chain class switch recombination event. We propose that vitamin A may alter S site accessibility to activation-induced deaminase and nonhomologous end-joining machinery, thereby influencing the isotype switch, antibody production, and protection against viral infections at mucosal sites.

  12. MHC class II B diversity in blue tits : A preliminary study

    NARCIS (Netherlands)

    Rivero-de Aguilar, Juan; Schut, Elske; Merino, Santiago; Martinez, Javier; Komdeur, Jan; Westerdahl, Helena

    In this study, we partly characterize major histocompatibility complex (MHC) class II B in the blue tit (Cyanistes caeruleus). A total of 22 individuals from three different European locations: Spain, The Netherlands, and Sweden were screened for MHC allelic diversity. The MHC genes were

  13. A comparative analysis of viral peptides presented by contemporary human and chimpanzee MHC class I molecules

    NARCIS (Netherlands)

    van Deutekom, Hanneke W. M.; Hoof, Ilka; Bontrop, Ronald E.; Keşmir, Can

    2011-01-01

    Genetic factors such as the MHC influence the immunocompetence of an individual. MHC genes are the most polymorphic genes in primates, which is often interpreted as an adaptation to establish good T cell responses to a wide range of (evolving) pathogens. Chimpanzee MHC (Patr) genes are less

  14. Transfer of heavy metals in the food chain earthworm Black-tailed godwit (Limosa limosa): Comparison of a polluted and a reference site in The Netherlands

    Energy Technology Data Exchange (ETDEWEB)

    Roodbergen, Maja [Department of Ecology and Environment, ALTERRA, PO Box 47, 6700 AA, Wageningen (Netherlands); Animal Ecology Group, Centre for Ecological and Evolutionary Studies, University of Groningen, Haren (Netherlands)], E-mail: maja.roodbergen@sovon.nl; Klok, Chris; Hout, Annemariet van der [Department of Ecology and Environment, ALTERRA, PO Box 47, 6700 AA, Wageningen (Netherlands)

    2008-12-01

    The Black-tailed godwit (Limosa limosa) is a migratory wader that favours wet meadows for breeding. The species has a Red List status in The Netherlands, as it strongly declined in numbers since the 1960s. Intensification of agriculture and land use change resulting in habitat loss are considered major causes of this decline. In some areas the breeding habitat is contaminated with heavy metals. Adult godwits mainly feed on earthworms in the breeding season, which are known to accumulate heavy metals from the soil. In this paper we investigate the transfer of heavy metals from the soil to the Black-tailed godwit, which may have an additive negative effect on the viability of local populations. We measured heavy metal concentrations in soil, earthworms, and godwit eggs and feathers at a polluted and a reference site. The results suggest that Lead, Mercury and Cadmium are transferred from the soil to godwits even though the species spends only a few months in the breeding area during the year.

  15. Transfer of heavy metals in the food chain earthworm Black-tailed godwit (Limosa limosa): Comparison of a polluted and a reference site in The Netherlands

    International Nuclear Information System (INIS)

    Roodbergen, Maja; Klok, Chris; Hout, Annemariet van der

    2008-01-01

    The Black-tailed godwit (Limosa limosa) is a migratory wader that favours wet meadows for breeding. The species has a Red List status in The Netherlands, as it strongly declined in numbers since the 1960s. Intensification of agriculture and land use change resulting in habitat loss are considered major causes of this decline. In some areas the breeding habitat is contaminated with heavy metals. Adult godwits mainly feed on earthworms in the breeding season, which are known to accumulate heavy metals from the soil. In this paper we investigate the transfer of heavy metals from the soil to the Black-tailed godwit, which may have an additive negative effect on the viability of local populations. We measured heavy metal concentrations in soil, earthworms, and godwit eggs and feathers at a polluted and a reference site. The results suggest that Lead, Mercury and Cadmium are transferred from the soil to godwits even though the species spends only a few months in the breeding area during the year

  16. Prospects for immunotherapy of MHC class I-deficient tumours

    Czech Academy of Sciences Publication Activity Database

    Bubeník, Jan

    2003-01-01

    Roč. 49, č. 3 (2003), s. 95-99 ISSN 0015-5500 Institutional research plan: CEZ:AV0Z5052915 Keywords : MHC class I * immunotherapy Subject RIV: FD - Oncology ; Hematology Impact factor: 0.527, year: 2003

  17. Exosomal cancer immunotherapy is independent of MHC molecules on exosomes.

    Science.gov (United States)

    Hiltbrunner, Stefanie; Larssen, Pia; Eldh, Maria; Martinez-Bravo, Maria-Jose; Wagner, Arnika K; Karlsson, Mikael C I; Gabrielsson, Susanne

    2016-06-21

    Peptide-loaded exosomes are promising cancer treatment vehicles; however, moderate T cell responses in human clinical trials indicate a need to further understand exosome-induced immunity. We previously demonstrated that antigen-loaded exosomes carry whole protein antigens and require B cells for inducing antigen-specific T cells. Therefore, we investigated the relative importance of exosomal major histocompatibility complex (MHC) class I for the induction of antigen-specific T cell responses and tumour protection. We show that ovalbumin-loaded dendritic cell-derived exosomes from MHCI-/- mice induce antigen-specific T cells at the same magnitude as wild type exosomes. Furthermore, exosomes lacking MHC class I, as well as exosomes with both MHC class I and II mismatch, induced tumour infiltrating T cells and increased overall survival to the same extent as syngeneic exosomes in B16 melanoma. In conclusion, T cell responses are independent of exosomal MHC/peptide complexes if whole antigen is present. This establishes the prospective of using impersonalised exosomes, and will greatly increase the feasibility of designing exosome-based vaccines or therapeutic approaches in humans.

  18. Cutting Edge: Impaired MHC Class I Expression in Mice Deficient for Nlrc5/CITA

    OpenAIRE

    Biswas, Amlan; Meissner, Torsten B.; Taro Kawai,; Kobayashi, Koichi S.

    2012-01-01

    MHC class I and class II are crucial for the adaptive immune system. Although regulation of MHC class II expression by CIITA (class II transactivator) has long been recognized, the mechanism of MHC class I transactivation has been largely unknown until the recent discovery of NLRC5/CITA. Here we show using Nlrc5-deficient mice that NLRC5 is required for both constitutive and inducible MHC class I expression. Loss of Nlrc5 resulted in severe reduction in the expression of MHC class I and relat...

  19. MHC Class II and Non-MHC Class II Genes Differentially Influence Humoral Immunity to Bacillus anthracis Lethal Factor and Protective Antigen

    Directory of Open Access Journals (Sweden)

    Judith A. James

    2012-12-01

    Full Text Available Anthrax Lethal Toxin consists of Protective Antigen (PA and Lethal Factor (LF, and current vaccination strategies focus on eliciting antibodies to PA. In human vaccination, the response to PA can vary greatly, and the response is often directed toward non-neutralizing epitopes. Variable vaccine responses have been shown to be due in part to genetic differences in individuals, with both MHC class II and other genes playing roles. Here, we investigated the relative contribution of MHC class II versus non-MHC class II genes in the humoral response to PA and LF immunization using three immunized strains of inbred mice: A/J (H-2k at the MHC class II locus, B6 (H-2b, and B6.H2k (H-2k. IgG antibody titers to LF were controlled primarily by the MHC class II locus, whereas IgG titers to PA were strongly influenced by the non-MHC class II genetic background. Conversely, the humoral fine specificity of reactivity to LF appeared to be controlled primarily through non-MHC class II genes, while the specificity of reactivity to PA was more dependent on MHC class II. Common epitopes, reactive in all strains, occurred in both LF and PA responses. These results demonstrate that MHC class II differentially influences humoral immune responses to LF and PA.

  20. Predicted MHC peptide binding promiscuity explains MHC class I 'hotspots' of antigen presentation defined by mass spectrometry eluted ligand data.

    Science.gov (United States)

    Jappe, Emma Christine; Kringelum, Jens; Trolle, Thomas; Nielsen, Morten

    2018-02-15

    Peptides that bind to and are presented by MHC class I and class II molecules collectively make up the immunopeptidome. In the context of vaccine development, an understanding of the immunopeptidome is essential, and much effort has been dedicated to its accurate and cost-effective identification. Current state-of-the-art methods mainly comprise in silico tools for predicting MHC binding, which is strongly correlated with peptide immunogenicity. However, only a small proportion of the peptides that bind to MHC molecules are, in fact, immunogenic, and substantial work has been dedicated to uncovering additional determinants of peptide immunogenicity. In this context, and in light of recent advancements in mass spectrometry (MS), the existence of immunological hotspots has been given new life, inciting the hypothesis that hotspots are associated with MHC class I peptide immunogenicity. We here introduce a precise terminology for defining these hotspots and carry out a systematic analysis of MS and in silico predicted hotspots. We find that hotspots defined from MS data are largely captured by peptide binding predictions, enabling their replication in silico. This leads us to conclude that hotspots, to a great degree, are simply a result of promiscuous HLA binding, which disproves the hypothesis that the identification of hotspots provides novel information in the context of immunogenic peptide prediction. Furthermore, our analyses demonstrate that the signal of ligand processing, although present in the MS data, has very low predictive power to discriminate between MS and in silico defined hotspots. © 2018 John Wiley & Sons Ltd.

  1. Identification of MHC class II restricted T‐cell‐mediated reactivity against MHC class I binding Mycobacterium tuberculosis peptides

    DEFF Research Database (Denmark)

    Wang, Mingjun; Tang, Sheila Tuyet; Stryhn, Anette

    2011-01-01

    Major histocompatibility complex (MHC) class I restricted cytotoxic T lymphocytes (CTL) are known to play an important role in the control of Mycobacterium tuberculosis infection so identification of CTL epitopes from M. tuberculosis is of importance for the development of effective peptide...

  2. Chlorpyrifos- and chlorpyrifos oxon-induced neurite retraction in pre-differentiated N2a cells is associated with transient hyperphosphorylation of neurofilament heavy chain and ERK 1/2

    Energy Technology Data Exchange (ETDEWEB)

    Sindi, Ramya A., E-mail: ramya.sindi2010@my.ntu.ac.uk [Interdisciplinary Biomedical Research Centre, School of Science and Technology, Nottingham Trent University, Clifton Lane, Nottingham NG11 8NS (United Kingdom); School of Applied Medical Sciences, Umm Al-Qura University, Makkah (Saudi Arabia); Harris, Wayne [Interdisciplinary Biomedical Research Centre, School of Science and Technology, Nottingham Trent University, Clifton Lane, Nottingham NG11 8NS (United Kingdom); Arnott, Gordon [School of Science and Technology, Nottingham Trent University, Nottingham NG11 8NS (United Kingdom); Flaskos, John [Laboratory of Biochemistry and Toxicology, School of Veterinary Medicine, Aristotle University of Thessaloniki, 54124 Thessaloniki (Greece); Lloyd Mills, Chris [School of Science and Technology, Nottingham Trent University, Nottingham NG11 8NS (United Kingdom); Hargreaves, Alan J., E-mail: alan.hargreaves@ntu.ac.uk [Interdisciplinary Biomedical Research Centre, School of Science and Technology, Nottingham Trent University, Clifton Lane, Nottingham NG11 8NS (United Kingdom)

    2016-10-01

    Chlorpyrifos (CPF) and CPF-oxon (CPO) are known to inhibit neurite outgrowth but little is known about their ability to induce neurite retraction in differentiating neuronal cells. The aims of this study were to determine the ability of these compounds to destabilize neurites and to identify the key molecular events involved. N2a cells were induced to differentiate for 20 h before exposure to CPF or CPO for 2–8 h. Fixed cell monolayers labeled with carboxyfluorescein succinimidyl ester or immunofluorescently stained with antibodies to tubulin (B512) or phosphorylated neurofilament heavy chain (Ta51) showed time- and concentration-dependent reductions in numbers and length of axon-like processes compared to the control, respectively, retraction of neurites being observed within 2 h of exposure by live cell imaging. Neurofilament disruption was also observed in treated cells stained by indirect immunofluorescence with anti-phosphorylated neurofilament heavy chain (NFH) monoclonal antibody SMI34, while the microtubule network was unaffected. Western blotting analysis revealed transiently increased levels of reactivity of Ta51 after 2 h exposure and reduced levels of reactivity of the same antibody following 8 h treatment with both compounds, whereas reactivity with antibodies to anti-total NFH or anti-tubulin was not affected. The alteration in NFH phosphorylation at 2 h exposure was associated with increased activation of extracellular signal-regulated protein kinase ERK 1/2. However, increased levels of phosphatase activity were observed following 8 h exposure. These findings suggest for the first time that organophosphorothionate pesticide-induced neurite retraction in N2a cells is associated with transient increases in NFH phosphorylation and ERK1/2 activation. - Highlights: • Chlorpyrifos and chlorpyrifos oxon induced rapid neurite retraction in N2a cells. • This occurred following transient hyperphosphorylation of ERK 1/2. • It was concomitant with

  3. Chlorpyrifos- and chlorpyrifos oxon-induced neurite retraction in pre-differentiated N2a cells is associated with transient hyperphosphorylation of neurofilament heavy chain and ERK 1/2

    International Nuclear Information System (INIS)

    Sindi, Ramya A.; Harris, Wayne; Arnott, Gordon; Flaskos, John; Lloyd Mills, Chris; Hargreaves, Alan J.

    2016-01-01

    Chlorpyrifos (CPF) and CPF-oxon (CPO) are known to inhibit neurite outgrowth but little is known about their ability to induce neurite retraction in differentiating neuronal cells. The aims of this study were to determine the ability of these compounds to destabilize neurites and to identify the key molecular events involved. N2a cells were induced to differentiate for 20 h before exposure to CPF or CPO for 2–8 h. Fixed cell monolayers labeled with carboxyfluorescein succinimidyl ester or immunofluorescently stained with antibodies to tubulin (B512) or phosphorylated neurofilament heavy chain (Ta51) showed time- and concentration-dependent reductions in numbers and length of axon-like processes compared to the control, respectively, retraction of neurites being observed within 2 h of exposure by live cell imaging. Neurofilament disruption was also observed in treated cells stained by indirect immunofluorescence with anti-phosphorylated neurofilament heavy chain (NFH) monoclonal antibody SMI34, while the microtubule network was unaffected. Western blotting analysis revealed transiently increased levels of reactivity of Ta51 after 2 h exposure and reduced levels of reactivity of the same antibody following 8 h treatment with both compounds, whereas reactivity with antibodies to anti-total NFH or anti-tubulin was not affected. The alteration in NFH phosphorylation at 2 h exposure was associated with increased activation of extracellular signal-regulated protein kinase ERK 1/2. However, increased levels of phosphatase activity were observed following 8 h exposure. These findings suggest for the first time that organophosphorothionate pesticide-induced neurite retraction in N2a cells is associated with transient increases in NFH phosphorylation and ERK1/2 activation. - Highlights: • Chlorpyrifos and chlorpyrifos oxon induced rapid neurite retraction in N2a cells. • This occurred following transient hyperphosphorylation of ERK 1/2. • It was concomitant with

  4. Flexibility of the myosin heavy chain: direct evidence that the region containing SH/sub 1/ and SH/sub 2/ can move 10 /Angstrom/ under the influence of nucleotide binding

    Energy Technology Data Exchange (ETDEWEB)

    Huston, E.E.; Grammer, J.C.; Yount, R.G.

    1988-12-13

    Previous experiments demonstrated that two thiols of skeletal myosin subfragment 1 (SF/sub 1/) could be oxidized to a disulfide bond by treatment with a 2-fold excess of 5,5'-dithiobis (2-nitrobenzoic acid) (DTNB) in the presence of MgADP. The resulting characteristic changes in the ATPase activities of SF/sub 1/ and the fact that MgADP was stably trapped at the active site, suggested that the two thiols cross-linked were SH/sub 1/ (Cys-707) and SH/sub 2/ (Cys-697) from the myosin heavy chain. To verify this suggestion, SF/sub 1/, after DTNB treatment as above, was treated with an excess of N-ethylmaleimide to block all accessible thiols. The single protein disulfide produced by DTNB oxidation was reduced with dithioerythritol and the modified SF/sub 1/ internally cross-linked with equimolar (/sup 14/C)p-phenylenedimaleimide (pPDM) in the presence of MgADP. After extensive trypsinization, the major /sup 14/C-labeled peptide was isolated, characterized, and shown to be Cys-Asn-Gly-Val-Leu-Gly-Ile-Arg-Ile-Cys-Arg, in which the two cysteines were cross-linked by pPDM. This peptide is known to contain SH/sub 2/ and SH/sub 1/ in this order and to come from residues 697-708 in the rabbit skeletal myosin heavy chain. Parallel experiments with (/sup 14/C)pPDM and unmodified SF/sub 1/ similar to those above gave an identical SH/sub 1/, SH/sub 2/ tryptic peptide, verifying earlier labeling results. These combined results demonstrate that SH/sub 1/ and SH/sub 2/ cross-linked by pPDM (12-13 /Angstrom/, S to S) or by oxidation with DTNB (2 /Angstrom/, S to S) can move a minimum of 10 /Angstrom/ under the influence of nucleotide binding. Because these residues are separated by only nine amino acids in the primary sequence, this small section of the heavy chain must possess extraordinary flexibility.

  5. Tapasin-related protein TAPBPR is an additional component of the MHC class I presentation pathway

    DEFF Research Database (Denmark)

    Boyle, Louise H; Hermann, Clemens; Boname, Jessica M

    2013-01-01

    Tapasin is an integral component of the peptide-loading complex (PLC) important for efficient peptide loading onto MHC class I molecules. We investigated the function of the tapasin-related protein, TAPBPR. Like tapasin, TAPBPR is widely expressed, IFN-γ-inducible, and binds to MHC class I coupled...... with β2-microglobulin in the endoplasmic reticulum. In contrast to tapasin, TAPBPR does not bind ERp57 or calreticulin and is not an integral component of the PLC. β2-microglobulin is essential for the association between TAPBPR and MHC class I. However, the association between TAPBPR and MHC class I...... occurs in the absence of a functional PLC, suggesting peptide is not required. Expression of TAPBPR decreases the rate of MHC class I maturation through the secretory pathway and prolongs the association of MHC class I on the PLC. The TAPBPR:MHC class I complex trafficks through the Golgi apparatus...

  6. Pan-specific prediction of peptide-MHC Class I complex stability, a correlate of T cell immunogenicity

    DEFF Research Database (Denmark)

    Rasmussen, Michael; Fenoy, Emilio; Harndahl, Mikkel

    2016-01-01

    Binding of peptides to MHC class I (MHC-I) molecules is the most selective event in the processing and presentation of Ags to CTL, and insights into the mechanisms that govern peptide-MHC-I binding should facilitate our understanding of CTL biology. Peptide-MHC-I interactions have traditionally b...

  7. Fine-mapping analysis of the MHC region for vitiligo based on a new Han-MHC reference panel.

    Science.gov (United States)

    Yang, Chao; Wu, Juan; Zhang, Xuelei; Wen, Leilei; Sun, Jingying; Cheng, Yuyan; Tang, Xianfa; Liang, Bo; Chen, Gang; Zhou, Fusheng; Cui, Yong; Zhang, Anping; Zhang, Xuejun; Zheng, Xiaodong; Yang, Sen; Sun, Liangdan

    2018-03-30

    Vitiligo is an immune-related disease with patchy depigmentation of skin and hair caused by selective destruction of melanocytes. In recent decades, many studies have shown the association between vitiligo and HLA genes; however, the results of Han Chinese are scarce. In this study, we performed a fine-mapping analysis of the MHC region in 2818 Han Chinese subjects through a widely used HLA imputation method with a newly built large-scale Han-MHC reference panel. Three new four-digit HLA alleles (HLA-DQB1 ∗ 02:02, HLA-DQA1 ∗ 02:01 and HLA-DPB1 ∗ 17:01) were identified to be associated with the risk of vitiligo, and four previously reported alleles were confirmed. Further conditional analysis revealed that two important variants, HLA-DQβ1 amino acid position 135 (OR = 1.79, P = 1.87 × 10 -11 ) and HLA-B amino acid positions 45-46 (OR = 1.44, P = 5.61 × 10 -11 ), conferred most of the MHC associations. Three-dimension ribbon models showed that the former is located within the β2 domain of the HLA-DQβ1 molecule, and the latter lies in the α1 domain of the HLA-B molecule, while both are involved in specific antigen presenting process. Finally, we summarized all significant signals in the MHC region to clarify their complex relationships, and 8.60% of phenotypic variance could be explained based on all reported variants in Han Chinese so far. Our findings highlight the complex genetic architecture of the MHC region for vitiligo in Han Chinese population and expand our understanding of the roles of HLA coding variants in the etiology of vitiligo. Copyright © 2018. Published by Elsevier B.V.

  8. cDNA cloning and primary structure analysis of invariant chain in ...

    African Journals Online (AJOL)

    cDNA cloning and primary structure analysis of invariant chain in Chinese Pengze crucian carp. X Liu, W Yu, J Li, F Chen, S Liu, C Wu, J Xu. Abstract. Invariant chain (Ii) plays an important role in MHC class II molecules assembly and exogenous peptide presentation in vertebrates. Although mammalian Ii has been ...

  9. In vitro studies of immunoglobulin heavy-chain binding protein (BiP, GRP78). Interactions of BiP with newly synthesized proteins and adenine nucleotides

    International Nuclear Information System (INIS)

    Kassenbrock, C.K.

    1988-01-01

    Here we examine the interaction of BiP with newly synthesized polypeptides in an in vitro protein translations-translocation system. We find that BiP forms tight complexes with nonglycosylated yeast invertase and incorrectly disulfide-bonded prolactin but not with glycosylated invertase or correctly disulfide-bonded prolactin. Moreover, BiP associates detectably only with completed chains of prolactin, not with chains undergoing synthesis. We conclude that BiP recognizes and binds with high affinity to aberrantly folded or aberrantly glycosylated polypeptides in vitro, but not to all nascent chains as they are folding. BiP also binds APT and can be purified by APT affinity chromatography. We show that submicromolar levels of ATP or ADP decrease the rate of absorption of 125 I-BiP to nitrocellulose filters coated with protein or nonionic detergents. ATP and ADP also protect portions of BiP from proteolytic degradation. In contrast, micromolar levels of AMP increase the rate of adsorption and the rate of proteolytic degradation of BiP. We also show that an ATPase activity co-purifies with BiP, but its slow turnover number suggests a regulatory, rather than a functional role. The BiP-associated ATPase shares several properties with the related cytoplasmic protein, HSC70/clathrin uncoating ATPase

  10. Altered phenotypic expression of immunoglobulin heavy-chain variable-region (VH) genes in Alicia rabbits probably reflects a small deletion in the VH genes closest to the joining region.

    Science.gov (United States)

    Allegrucci, M; Newman, B A; Young-Cooper, G O; Alexander, C B; Meier, D; Kelus, A S; Mage, R G

    1990-07-01

    Rabbits of the Alicia strain have a mutation (ali) that segregates with the immunoglobulin heavy-chain (lgh) locus and has a cis effect upon the expression of heavy-chain variable-region (VH) genes encoding the a2 allotype. In heterozygous a1/ali or a3/ali rabbits, serum immunoglobulins are almost entirely the products of the normal a1 or a3 allele and only traces of a2 immunoglobulin are detectable. Adult homozygous ali/ali rabbits likewise have normal immunoglobulin levels resulting from increased production of a-negative immunoglobulins and some residual ability to produce the a2 allotype. By contrast, the majority of the immunoglobulins of wild-type a2 rabbits are a2-positive and only a small percentage are a-negative. Genomic DNAs from homozygous mutant and wild-type animals were indistinguishable by Southern analyses using a variety of restriction enzyme digests and lgh probes. However, when digests with infrequently cutting enzymes were analyzed by transverse alternating-field electrophoresis, the ali DNA fragments were 10-15 kilobases smaller than the wild type. These fragments hybridized to probes both for VH and for a region of DNA a few kilobases downstream of the VH genes nearest the joining region. We suggest that this relatively small deletion affects a segment containing 3' VH genes with important regulatory functions, the loss of which leads to the ali phenotype. These results, and the fact that the 3' VH genes rearrange early in B-cell development, indicate that the 3' end of the VH locus probably plays a key role in regulation of VH gene expression.

  11. Impact of substrate contamination with mycotoxins, heavy metals and pesticides on the growth performance and composition of black soldier fly larvae (Hermetia illucens) for use in the feed and food value chain.

    Science.gov (United States)

    Purschke, Benedict; Scheibelberger, Rafaela; Axmann, Sonja; Adler, Andreas; Jäger, Henry

    2017-08-01

    Edible insects have emerged as an alternative and sustainable source of high-quality, animal-derived protein and fat for livestock production or direct human nutrition. During the production of insects, substrate quality is a key parameter to assure optimal insect biomass gain as well as the safety of feed and food derived from commercially reared insects. Therefore, the influence of a realistic substrate contamination scenario on growth performance and accumulation behaviour of black soldier fly larvae (BSFL; Hermetia illucens L.) was investigated. Newly hatched larvae were fed on a corn-based substrate spiked with heavy metals (As, Cd, Cr, Hg, Ni, Pb), mycotoxins (aflatoxins B1/B2/G2, deoxynivalenol, ochratoxin A, zearalenone) and pesticides (chlorpyrifos, chlorpyrifos-methyl, pirimiphos-methyl) under defined breeding conditions (10 days, 28°C, 67% relative humidity). The extent of contaminants' bioaccumulation in the larval tissue as well as the effect on growing determinants were examined. The applied heavy metal substrate contamination was shown to impair larval growing indicated by significantly lower post-trial larval mass and feed conversion ratio (FCR). Cd and Pb accumulation factors of 9 and 2, respectively, were determined, while the concentrations of other heavy metals in the larvae remained below the initial substrate concentration. In contrast, mycotoxins and pesticides have neither been accumulated in the larval tissue nor significantly affected the growing determinants in comparison with the control. The use of BSFL as livestock feed requires contaminant monitoring - especially for Cd and Pb - in the substrates as well as in feedstuff containing BSFL to ensure feed and food safety along the value chain.

  12. The diabetogenic mouse MHC class II molecule I-A[subscript g7] is endowed with a switch that modulates TCR affinity

    Energy Technology Data Exchange (ETDEWEB)

    Yoshida, Kenji; Corper, Adam L.; Herro, Rana; Jabri, Bana; Wilson, Ian A.; Teyton, Luc (Scripps); (UC)

    2011-11-16

    Genetic susceptibility to autoimmunity is frequently associated with specific MHC alleles. Diabetogenic MHC class II molecules, such as human HLA-DQ8 and mouse I-A{sub g7}, typically have a small, uncharged amino acid residue at position 57 of their {beta} chain ({beta}57); this results in the absence of a salt bridge between {beta}57 and Arg{alpha}76, which is adjacent to the P9 pocket of the peptide-binding groove. However, the influence of Arg{alpha}76 on the selection of the TCR repertoire remains unknown, particularly when the MHC molecule binds a peptide with a neutral amino acid residue at position P9. Here, we have shown that diabetogenic MHC class II molecules bound to a peptide with a neutral P9 residue primarily selected and expanded cells expressing TCRs bearing a negatively charged residue in the first segment of their complementarity determining region 3{beta}. The crystal structure of one such TCR in complex with I-A{sub g7} bound to a peptide containing a neutral P9 residue revealed that a network of favorable long-range (greater than 4 {angstrom}) electrostatic interactions existed among Arg{alpha}76, the neutral P9 residue, and TCR, which supported the substantially increased TCR/peptide-MHC affinity. This network could be modulated or switched to a lower affinity interaction by the introduction of a negative charge at position P9 of the peptide. Our results support the existence of a switch at residue {beta}57 of the I-Ag7 and HLA-DQ8 class II molecules and potentially link normal thymic TCR selection with abnormal peripheral behavior.

  13. Interferon beta 1, an intermediate in the tumor necrosis factor alpha- induced increased MHC class I expression and an autocrine regulator of the constitutive MHC class I expression

    OpenAIRE

    1987-01-01

    In conclusion, our observations indicate that the constitutive MHC class I expression is regulated by autocrine production of IFN-beta 1. TNF-alpha acts as an enhancer of the autocrine production of IFN-beta 1, and consequently as an enhancer of the MHC class I expression and viral protection.

  14. NetMHC-3.0: accurate web accessible predictions of human, mouse and monkey MHC class I affinities for peptides of length 8-11

    DEFF Research Database (Denmark)

    Lundegaard, Claus; Lamberth, K; Harndahl, M

    2008-01-01

    NetMHC-3.0 is trained on a large number of quantitative peptide data using both affinity data from the Immune Epitope Database and Analysis Resource (IEDB) and elution data from SYFPEITHI. The method generates high-accuracy predictions of major histocompatibility complex (MHC): peptide binding...

  15. Neuronal MHC Class I Expression Is Regulated by Activity Driven Calcium Signaling.

    Directory of Open Access Journals (Sweden)

    Dan Lv

    Full Text Available MHC class I (MHC-I molecules are important components of the immune system. Recently MHC-I have been reported to also play important roles in brain development and synaptic plasticity. In this study, we examine the molecular mechanism(s underlying activity-dependent MHC-I expression using hippocampal neurons. Here we report that neuronal expression level of MHC-I is dynamically regulated during hippocampal development after birth in vivo. Kainic acid (KA treatment significantly increases the expression of MHC-I in cultured hippocampal neurons in vitro, suggesting that MHC-I expression is regulated by neuronal activity. In addition, KA stimulation decreased the expression of pre- and post-synaptic proteins. This down-regulation is prevented by addition of an MHC-I antibody to KA treated neurons. Further studies demonstrate that calcium-dependent protein kinase C (PKC is important in relaying KA simulation activation signals to up-regulated MHC-I expression. This signaling cascade relies on activation of the MAPK pathway, which leads to increased phosphorylation of CREB and NF-κB p65 while also enhancing the expression of IRF-1. Together, these results suggest that expression of MHC-I in hippocampal neurons is driven by Ca2+ regulated activation of the MAPK signaling transduction cascade.

  16. MHC I stabilizing potential of computer-designed octapeptides.

    Science.gov (United States)

    Wisniewska, Joanna M; Jäger, Natalie; Freier, Anja; Losch, Florian O; Wiesmüller, Karl-Heinz; Walden, Peter; Wrede, Paul; Schneider, Gisbert; Hiss, Jan A

    2010-01-01

    Experimental results are presented for 180 in silico designed octapeptide sequences and their stabilizing effects on the major histocompatibility class I molecule H-2K(b). Peptide sequence design was accomplished by a combination of an ant colony optimization algorithm with artificial neural network classifiers. Experimental tests yielded nine H-2K(b) stabilizing and 171 nonstabilizing peptides. 28 among the nonstabilizing octapeptides contain canonical motif residues known to be favorable for MHC I stabilization. For characterization of the area covered by stabilizing and non-stabilizing octapeptides in sequence space, we visualized the distribution of 100,603 octapeptides using a self-organizing map. The experimental results present evidence that the canonical sequence motives of the SYFPEITHI database on their own are insufficient for predicting MHC I protein stabilization.

  17. MHC I Stabilizing Potential of Computer-Designed Octapeptides

    Directory of Open Access Journals (Sweden)

    Joanna M. Wisniewska

    2010-01-01

    Full Text Available Experimental results are presented for 180 in silico designed octapeptide sequences and their stabilizing effects on the major histocompatibility class I molecule H-2Kb. Peptide sequence design was accomplished by a combination of an ant colony optimization algorithm with artificial neural network classifiers. Experimental tests yielded nine H-2Kb stabilizing and 171 nonstabilizing peptides. 28 among the nonstabilizing octapeptides contain canonical motif residues known to be favorable for MHC I stabilization. For characterization of the area covered by stabilizing and non-stabilizing octapeptides in sequence space, we visualized the distribution of 100,603 octapeptides using a self-organizing map. The experimental results present evidence that the canonical sequence motives of the SYFPEITHI database on their own are insufficient for predicting MHC I protein stabilization.

  18. Complex assembly, crystallization and preliminary X-ray crystallographic studies of duck MHC class I molecule

    International Nuclear Information System (INIS)

    Zhang, Jianhua; Chen, Yong; Gao, Feng; Chen, Weihong; Qi, Jianxun; Xia, Chun

    2009-01-01

    Using a peptide derived from H5N1, a complex of duck MHC class I molecule (DuMHC I) with duck β 2 -microglobulin (Duβ 2 m) was assembled and crystallized. Initial structure analysis indicated that the crystals did not contain the complete DuMHC I complex but instead contained DuMHC I α3-domain and Duβ 2 m subunits. In order to understand the biological properties of the immune systems of waterfowl and to establish a system for structural studies of duck class I major histocompatibility complex (DuMHC I), a complex of DuMHC I with duck β 2 -microglobulin (Duβ 2 m) and the peptide AEIEDLIF (AF8) derived from H5N1 NP residues 251–258 was assembled. The complex was crystallized; the crystals belonged to space group C222 1 , with unit-cell parameters a = 54.7, b = 72.4, c = 102.2 Å, and diffracted to 2.3 Å resolution. Matthews coefficient calculation and initial structure determination by molecular replacement showed that the crystals did not contain the whole DuMHC I complex, but instead contained the DuMHC I α3 domain and a Duβ2m molecule (DuMHC I α3+β2m). Another complex of DuMHC I with the peptide IDWFDGKE derived from a chicken fusion protein also generated the same results. The stable structure of DuMHC I α3+β2m may reflect some unique characteristics of DuMHC I and pave the way for novel MHC structure-related studies in the future

  19. Tumour MHC class I downregulation and immunotherapy (Review)

    Czech Academy of Sciences Publication Activity Database

    Bubeník, Jan

    2003-01-01

    Roč. 10, č. 6 (2003), s. 2005-2008 ISSN 1021-335X R&D Projects: GA MZd NC7148; GA ČR GA301/01/0985; GA AV ČR IAA5052203 Institutional research plan: CEZ:AV0Z5052915 Keywords : tumour vaccines * MHC class I downregulation Subject RIV: FD - Oncology ; Hematology Impact factor: 1.256, year: 2003

  20. Automated benchmarking of peptide-MHC class I binding predictions

    Science.gov (United States)

    Trolle, Thomas; Metushi, Imir G.; Greenbaum, Jason A.; Kim, Yohan; Sidney, John; Lund, Ole; Sette, Alessandro; Peters, Bjoern; Nielsen, Morten

    2015-01-01

    Motivation: Numerous in silico methods predicting peptide binding to major histocompatibility complex (MHC) class I molecules have been developed over the last decades. However, the multitude of available prediction tools makes it non-trivial for the end-user to select which tool to use for a given task. To provide a solid basis on which to compare different prediction tools, we here describe a framework for the automated benchmarking of peptide-MHC class I binding prediction tools. The framework runs weekly benchmarks on data that are newly entered into the Immune Epitope Database (IEDB), giving the public access to frequent, up-to-date performance evaluations of all participating tools. To overcome potential selection bias in the data included in the IEDB, a strategy was implemented that suggests a set of peptides for which different prediction methods give divergent predictions as to their binding capability. Upon experimental binding validation, these peptides entered the benchmark study. Results: The benchmark has run for 15 weeks and includes evaluation of 44 datasets covering 17 MHC alleles and more than 4000 peptide-MHC binding measurements. Inspection of the results allows the end-user to make educated selections between participating tools. Of the four participating servers, NetMHCpan performed the best, followed by ANN, SMM and finally ARB. Availability and implementation: Up-to-date performance evaluations of each server can be found online at http://tools.iedb.org/auto_bench/mhci/weekly. All prediction tool developers are invited to participate in the benchmark. Sign-up instructions are available at http://tools.iedb.org/auto_bench/mhci/join. Contact: mniel@cbs.dtu.dk or bpeters@liai.org Supplementary information: Supplementary data are available at Bioinformatics online. PMID:25717196

  1. Heavy leptons

    International Nuclear Information System (INIS)

    Smith, C.H.L.

    1977-01-01

    The possibility that a new lepton may exist is discussed under the headings; theoretical reasons for the introduction of heavy leptons, classification of heavy leptons (ortho and paraleptons), discrimination between different types of lepton, decays of charged heavy leptons, production of charged heavy leptons (in e + e - storage rings, neutrino production, photoproduction, and hadroproduction), neutral heavy leptons, and hadroleptons. (U.K.)

  2. MHC Class II haplotypes of Colombian Amerindian tribes

    Science.gov (United States)

    Yunis, Juan J.; Yunis, Edmond J.; Yunis, Emilio

    2013-01-01

    We analyzed 1041 individuals belonging to 17 Amerindian tribes of Colombia, Chimila, Bari and Tunebo (Chibcha linguistic family), Embera, Waunana (Choco linguistic family), Puinave and Nukak (Maku-Puinave linguistic families), Cubeo, Guanano, Tucano, Desano and Piratapuyo (Tukano linguistic family), Guahibo and Guayabero (Guayabero Linguistic Family), Curripaco and Piapoco (Arawak linguistic family) and Yucpa (Karib linguistic family). for MHC class II haplotypes (HLA-DRB1, DQA1, DQB1). Approximately 90% of the MHC class II haplotypes found among these tribes are haplotypes frequently encountered in other Amerindian tribes. Nonetheless, striking differences were observed among Chibcha and non-Chibcha speaking tribes. The DRB1*04:04, DRB1*04:11, DRB1*09:01 carrying haplotypes were frequently found among non-Chibcha speaking tribes, while the DRB1*04:07 haplotype showed significant frequencies among Chibcha speaking tribes, and only marginal frequencies among non-Chibcha speaking tribes. Our results suggest that the differences in MHC class II haplotype frequency found among Chibcha and non-Chibcha speaking tribes could be due to genetic differentiation in Mesoamerica of the ancestral Amerindian population into Chibcha and non-Chibcha speaking populations before they entered into South America. PMID:23885196

  3. Polymorphisms of the FOXF1 and MHC locus genes in individuals undergoing esophageal acid reflux assessments.

    Science.gov (United States)

    Lam, C; Liu, W F; Bel, R D; Chan, K; Miller, L; Brown, M C; Chen, Z; Cheng, D; Patel, D; Xu, W; Darling, G E; Liu, G

    2017-02-01

    Gastroesophageal reflux disease (GERD) may lead to Barrett's esophagus (BE). Previously, a large genome-wide association study found two germline markers to be associated with BE, FOXF1 rs9936833 (C allele) and MHC rs9257809 (A allele). This study evaluated whether these two polymorphisms are associated with gastroesphageal acid reflux as measured by 24-hour pH testing. Patients with acid reflux symptoms referred for esophageal manometry and 24-hour pH monitoring at University Health Network (Toronto, ON) were enrolled. DNA extracted from blood was genotyped using a Taqman Polymerase Chain Reaction (PCR) assay. DeMeester scores of ≥14.7 or prior evidence of reflux esophagitis on endoscopy defined individuals with esophageal acid reflux. Logistic regression analysis, adjusted for clinical risk factors, was used to calculate odds ratios with 95% confidence intervals for each polymorphism in relation to the presence of acid reflux. Of 182 patients, the median age was 50 years and 62% were female; 95 (52%) met the definition of GERD. In the multivariable analysis, both FOXF1 rs9936833 (OR = 1.82; 95%CI: 1.12-2.96; P = 0.02) and MHC rs9257809 (OR = 9.36; 95%CI: 2.92-29.99; P acid reflux. When both polymorphisms were placed in the same model, the adjusted ORs were 2.10 (95%CI: 1.24-3.53; P = 0.005) and 10.95 (95%CI: 3.32-36.09; P acid reflux suggests a potential pathophysiologic mechanism for the role of genetic influences in BE development. © 2016 International Society for Diseases of the Esophagus.

  4. Absence of linkage between MHC and a gene involved in susceptibility to human schistosomiasis

    Directory of Open Access Journals (Sweden)

    Chiarella J.M.

    1998-01-01

    Full Text Available Six hundred million people are at risk of infection by Schistosoma mansoni. MHC haplotypes have been reported to segregate with susceptibility to schistosomiasis in murine models. In humans, a major gene related to susceptibility/resistance to infection by S. mansoni (SM1 and displaying the mean fecal egg count as phenotype was detected by segregation analysis. This gene displayed a codominant mode of inheritance with an estimated frequency of 0.20-0.25 for the deleterious allele and accounted for more than 50% of the variance of infection levels. To determine if the SM1 gene segregates with the human MHC chromosomal region, we performed a linkage study by the lod score method. We typed for HLA-A, B, C, DR and DQ antigens in 11 informative families from an endemic area for schistosomiasis in Bahia, Brazil, by the microlymphocytotoxicity technique. HLA-DR typing by the polymerase chain reaction with sequence-specific primers (PCR-SSP and HLA-DQ were confirmed by PCR-sequence-specific oligonucleotide probes (PCR-SSOP. The lod scores for the different q values obtained clearly indicate that there is no physical linkage between HLA and SM1 genes. Thus, susceptibility or resistance to schistosomiasis, as defined by mean fecal egg count, is not primarily dependent on the host's HLA profile. However, if the HLA molecule plays an important role in specific immune responses to S. mansoni, this may involve the development of the different clinical aspects of the disease such as granuloma formation and development of hepatosplenomegaly.

  5. Immunotherapy of MHC class I-deficient tumours and epigenetic upregulation of MHC class I molecules on tumour cells

    Czech Academy of Sciences Publication Activity Database

    Reiniš, Milan; Manning, Jasper; Indrová, Marie; Přibylová, Hana; Bieblová, Jana; Šímová, Jana; Bubeník, Jan

    2007-01-01

    Roč. 20, Suppl. 1 (2007), S29-S29 ISSN 1107-3756. [World Congress on Advances in Oncology /12./ and International Symposium on Molecular Medicine /10./. 11.10.2007-12.10.2007, Hernissos] R&D Projects: GA ČR GA301/04/0492; GA ČR GA301/07/1410 Institutional research plan: CEZ:AV0Z50520514 Keywords : Immunotherapy * MHC I-deficient tumours * epigenetics Subject RIV: EB - Genetics ; Molecular Biology

  6. FOXP1 suppresses immune response signatures and MHC class II expression in activated B-cell-like diffuse large B-cell lymphomas

    DEFF Research Database (Denmark)

    Brown, P J; Wong, K K; Felce, S L

    2016-01-01

    The FOXP1 (forkhead box P1) transcription factor is a marker of poor prognosis in diffuse large B-cell lymphoma (DLBCL). Here microarray analysis of FOXP1-silenced DLBCL cell lines identified differential regulation of immune response signatures and major histocompatibility complex class II (MHC II......) genes as some of the most significant differences between germinal center B-cell (GCB)-like DLBCL with full-length FOXP1 protein expression versus activated B-cell (ABC)-like DLBCL expressing predominantly short FOXP1 isoforms. In an independent primary DLBCL microarray data set, multiple MHC II genes......, including human leukocyte antigen DR alpha chain (HLA-DRA), were inversely correlated with FOXP1 transcript expression (PABC-DLBCL cells led to increased cell-surface expression of HLA-DRA and CD74. In R-CHOP (rituximab, cyclophosphamide, doxorubicin, vincristine and prednisone...

  7. MHC class II deficiency: Report of a novel mutation and special review.

    Science.gov (United States)

    Farrokhi, S; Shabani, M; Aryan, Z; Zoghi, S; Krolo, A; Boztug, K; Rezaei, N

    The MHC II deficiency is a rare autosomal recessive primary immunodeficiency syndrome with increased susceptibility to respiratory and gastrointestinal infections, failure to thrive and early mortality. This syndrome is caused by mutations in transcription regulators of the MHC II gene and results in development of blind lymphocytes due to the lack of indicatory MHC II molecules. Despite homogeneity of clinical manifestations of patients with MHC II deficiency, the genetic defects underlying this disease are heterogeneous. Herein, we report an Iranian patient with MHC II deficiency harbouring a novel mutation in RFXANK and novel misleading clinical features. He had ataxic gait and dysarthria from 30 months of age. Epidemiology, clinical and immunological features, therapeutic options and prognosis of patients with MHC II are reviewed in this paper. Copyright © 2017 SEICAP. Published by Elsevier España, S.L.U. All rights reserved.

  8. The Intensity of Human Body Odors and the MHC: Should We Expect a Link?

    OpenAIRE

    Claus Wedekind; Thomas Seebeck; Florence Bettens; Alexander J. Paepke

    2006-01-01

    It is now well established that genes within the major histocompatibility complex (MHC) somehow affect the production of body odors in several vertebrates, including humans. Here we discuss whether variation in the intensity of body odors may be influenced by the MHC. In order to examine this question, we have to control for MHC-linked odor perception on the smeller's side. Such a control is necessary because the perception of pleasantness and intensity seem to be confounded, a...

  9. Sibling rivalry: competition between MHC class II family members inhibits immunity.

    Science.gov (United States)

    Denzin, Lisa K; Cresswell, Peter

    2013-01-01

    Peptide loading of major histocompatibility complex (MHC) class II molecules in the endosomes and lysosomes of antigen-presenting cells is catalyzed by human leukocyte antigen-DM (HLA-DM) and modulated by HLA-DO. In a structural study in this issue, Guce et al. show that HLA-DO is an MHC class II mimic and functions as a competitive and essentially irreversible inhibitor of HLA-DM activity, thereby inhibiting MHC class II antigen presentation.

  10. Ubiquitination regulates MHC class II-peptide complex retention and degradation in dendritic cells

    OpenAIRE

    Walseng, Even; Furuta, Kazuyuki; Bosch, Berta; Weih, Karis A.; Matsuki, Yohei; Bakke, Oddmund; Ishido, Satoshi; Roche, Paul A.

    2010-01-01

    The expression and turnover of MHC class II-peptide complexes (pMHC-II) on the surface of dendritic cells (DCs) is essential for their ability to activate CD4 T cells efficiently. The half-life of surface pMHC-II is significantly greater in activated (mature) DCs than in resting (immature) DCs, but the molecular mechanism leading to this difference remains unknown. We now show that ubiquitination of pMHC-II by the E3 ubiquitin ligase membrane-associated RING-CH 1 (March-I) regulates surface e...

  11. High levels of diversity characterize mandrill (Mandrillus sphinx) Mhc-DRB sequences.

    Science.gov (United States)

    Abbott, Kristin M; Wickings, E Jean; Knapp, Leslie A

    2006-08-01

    The major histocompatibility complex (MHC) is highly polymorphic in most primate species studied thus far. The rhesus macaque (Macaca mulatta) has been studied extensively and the Mhc-DRB region demonstrates variability similar to humans. The extent of MHC diversity is relatively unknown for other Old World monkeys (OWM), especially among genera other than Macaca. A molecular survey of the Mhc-DRB region in mandrills (Mandrillus sphinx) revealed extensive variability, suggesting that other OWMs may also possess high levels of Mhc-DRB polymorphism. In the present study, 33 Mhc-DRB loci were identified from only 13 animals. Eleven were wild-born and presumed to be unrelated and two were captive-born twins. Two to seven different sequences were identified for each individual, suggesting that some mandrills may have as many as four Mhc-DRB loci on a single haplotype. From these sequences, representatives of at least six Mhc-DRB loci or lineages were identified. As observed in other primates, some new lineages may have arisen through the process of gene conversion. These findings indicate that mandrills have Mhc-DRB diversity not unlike rhesus macaques and humans.

  12. MHC2NNZ: A novel peptide binding prediction approach for HLA DQ molecules

    Science.gov (United States)

    Xie, Jiang; Zeng, Xu; Lu, Dongfang; Liu, Zhixiang; Wang, Jiao

    2017-07-01

    The major histocompatibility complex class II (MHC-II) molecule plays a crucial role in immunology. Computational prediction of MHC-II binding peptides can help researchers understand the mechanism of immune systems and design vaccines. Most of the prediction algorithms for MHC-II to date have made large efforts in human leukocyte antigen (HLA, the name of MHC in Human) molecules encoded in the DR locus. However, HLA DQ molecules are equally important and have only been made less progress because it is more difficult to handle them experimentally. In this study, we propose an artificial neural network-based approach called MHC2NNZ to predict peptides binding to HLA DQ molecules. Unlike previous artificial neural network-based methods, MHC2NNZ not only considers sequence similarity features but also captures the chemical and physical properties, and a novel method incorporating these properties is proposed to represent peptide flanking regions (PFR). Furthermore, MHC2NNZ improves the prediction accuracy by combining with amino acid preference at more specific positions of the peptides binding core. By evaluating on 3549 peptides binding to six most frequent HLA DQ molecules, MHC2NNZ is demonstrated to outperform other state-of-the-art MHC-II prediction methods.

  13. Structure of a Pheromone Receptor-Associated Mhc Molecule With An Open And Empty Groove

    Energy Technology Data Exchange (ETDEWEB)

    Olson, R.; Huey-Tubman, K.E.; Dulac, C.; Bjorkman, P.J.; /Caltech /Harvard U.

    2006-10-06

    Neurons in the murine vomeronasal organ (VNO) express a family of class Ib major histocompatibility complex (MHC) proteins (M10s) that interact with the V2R class of VNO receptors. This interaction may play a direct role in the detection of pheromonal cues that initiate reproductive and territorial behaviors. The crystal structure of M10.5, an M10 family member, is similar to that of classical MHC molecules. However, the M10.5 counterpart of the MHC peptide-binding groove is open and unoccupied, revealing the first structure of an empty class I MHC molecule. Similar to empty MHC molecules, but unlike peptide-filled MHC proteins and non-peptide-binding MHC homologs, M10.5 is thermally unstable, suggesting that its groove is normally occupied. However, M10.5 does not bind endogenous peptides when expressed in mammalian cells or when offered a mixture of class I-binding peptides. The F pocket side of the M10.5 groove is open, suggesting that ligands larger than 8-10-mer class I-binding peptides could fit by extending out of the groove. Moreover, variable residues point up from the groove helices, rather than toward the groove as in classical MHC structures. These data suggest that M10s are unlikely to provide specific recognition of class I MHC-binding peptides, but are consistent with binding to other ligands, including proteins such as the V2Rs.

  14. Structure of a pheromone receptor-associated MHC molecule with an open and empty groove.

    Directory of Open Access Journals (Sweden)

    2005-08-01

    Full Text Available Neurons in the murine vomeronasal organ (VNO express a family of class Ib major histocompatibility complex (MHC proteins (M10s that interact with the V2R class of VNO receptors. This interaction may play a direct role in the detection of pheromonal cues that initiate reproductive and territorial behaviors. The crystal structure of M10.5, an M10 family member, is similar to that of classical MHC molecules. However, the M10.5 counterpart of the MHC peptide-binding groove is open and unoccupied, revealing the first structure of an empty class I MHC molecule. Similar to empty MHC molecules, but unlike peptide-filled MHC proteins and non-peptide-binding MHC homologs, M10.5 is thermally unstable, suggesting that its groove is normally occupied. However, M10.5 does not bind endogenous peptides when expressed in mammalian cells or when offered a mixture of class I-binding peptides. The F pocket side of the M10.5 groove is open, suggesting that ligands larger than 8-10-mer class I-binding peptides could fit by extending out of the groove. Moreover, variable residues point up from the groove helices, rather than toward the groove as in classical MHC structures. These data suggest that M10s are unlikely to provide specific recognition of class I MHC-binding peptides, but are consistent with binding to other ligands, including proteins such as the V2Rs.

  15. Establishment of a quantitative ELISA capable of determining peptide - MHC class I interaction

    DEFF Research Database (Denmark)

    Sylvester-Hvid, C; Kristensen, N; Blicher, T

    2002-01-01

    dependent manner. Here, we exploit the availability of these molecules to generate a quantitative ELISA-based assay capable of measuring the affinity of the interaction between peptide and MHC-I. This assay is simple and sensitive, and one can easily envisage that the necessary reagents, standards......Many different assays for measuring peptide-MHC interactions have been suggested over the years. Yet, there is no generally accepted standard method available. We have recently generated preoxidized recombinant MHC class I molecules (MHC-I) which can be purified to homogeneity under denaturing...

  16. NetMHC-3.0: accurate web accessible predictions of human, mouse and monkey MHC class I affinities for peptides of length 8-11.

    Science.gov (United States)

    Lundegaard, Claus; Lamberth, Kasper; Harndahl, Mikkel; Buus, Søren; Lund, Ole; Nielsen, Morten

    2008-07-01

    NetMHC-3.0 is trained on a large number of quantitative peptide data using both affinity data from the Immune Epitope Database and Analysis Resource (IEDB) and elution data from SYFPEITHI. The method generates high-accuracy predictions of major histocompatibility complex (MHC): peptide binding. The predictions are based on artificial neural networks trained on data from 55 MHC alleles (43 Human and 12 non-human), and position-specific scoring matrices (PSSMs) for additional 67 HLA alleles. As only the MHC class I prediction server is available, predictions are possible for peptides of length 8-11 for all 122 alleles. artificial neural network predictions are given as actual IC(50) values whereas PSSM predictions are given as a log-odds likelihood scores. The output is optionally available as download for easy post-processing. The training method underlying the server is the best available, and has been used to predict possible MHC-binding peptides in a series of pathogen viral proteomes including SARS, Influenza and HIV, resulting in an average of 75-80% confirmed MHC binders. Here, the performance is further validated and benchmarked using a large set of newly published affinity data, non-redundant to the training set. The server is free of use and available at: http://www.cbs.dtu.dk/services/NetMHC.

  17. An integrated tool to study MHC region: accurate SNV detection and HLA genes typing in human MHC region using targeted high-throughput sequencing.

    Directory of Open Access Journals (Sweden)

    Hongzhi Cao

    Full Text Available The major histocompatibility complex (MHC is one of the most variable and gene-dense regions of the human genome. Most studies of the MHC, and associated regions, focus on minor variants and HLA typing, many of which have been demonstrated to be associated with human disease susceptibility and metabolic pathways. However, the detection of variants in the MHC region, and diagnostic HLA typing, still lacks a coherent, standardized, cost effective and high coverage protocol of clinical quality and reliability. In this paper, we presented such a method for the accurate detection of minor variants and HLA types in the human MHC region, using high-throughput, high-coverage sequencing of target regions. A probe set was designed to template upon the 8 annotated human MHC haplotypes, and to encompass the 5 megabases (Mb of the extended MHC region. We deployed our probes upon three, genetically diverse human samples for probe set evaluation, and sequencing data show that ∼97% of the MHC region, and over 99% of the genes in MHC region, are covered with sufficient depth and good evenness. 98% of genotypes called by this capture sequencing prove consistent with established HapMap genotypes. We have concurrently developed a one-step pipeline for calling any HLA type referenced in the IMGT/HLA database from this target capture sequencing data, which shows over 96% typing accuracy when deployed at 4 digital resolution. This cost-effective and highly accurate approach for variant detection and HLA typing in the MHC region may lend further insight into immune-mediated diseases studies, and may find clinical utility in transplantation medicine research. This one-step pipeline is released for general evaluation and use by the scientific community.

  18. Polymorphism at Expressed DQ and DR Loci in Five Common Equine MHC Haplotypes

    Science.gov (United States)

    Miller, Donald; Tallmadge, Rebecca L.; Binns, Matthew; Zhu, Baoli; Mohamoud, Yasmin Ali; Ahmed, Ayeda; Brooks, Samantha A.; Antczak, Douglas F.

    2016-01-01

    The polymorphism of Major Histocompatibility Complex (MHC) class II DQ and DR genes in five common Equine Leukocyte Antigen (ELA) haplotypes was determined through sequencing of mRNA transcripts isolated from lymphocytes of eight ELA homozygous horses. Ten expressed MHC class II genes were detected in horses of the ELA-A3 haplotype carried by the donor horses of the equine Bacterial Artificial Chromosome (BAC) library and the reference genome sequence: four DR genes and six DQ genes. The other four ELA haplotypes contained at least eight expressed polymorphic MHC class II loci. Next Generation Sequencing (NGS) of genomic DNA of these four MHC haplotypes revealed stop codons in the DQA3 gene in the ELA-A2, ELA-A5, and ELA-A9 haplotypes. Few NGS reads were obtained for the other MHC class II genes that were not amplified in these horses. The amino acid sequences across haplotypes contained locus-specific residues, and the locus clusters produced by phylogenetic analysis were well supported. The MHC class II alleles within the five tested haplotypes were largely non-overlapping between haplotypes. The complement of equine MHC class II DQ and DR genes appears to be well conserved between haplotypes, in contrast to the recently described variation in class I gene loci between equine MHC haplotypes. The identification of allelic series of equine MHC class II loci will aid comparative studies of mammalian MHC conservation and evolution and may also help to interpret associations between the equine MHC class II region and diseases of the horse. PMID:27889800

  19. Cheetah paradigm revisited: MHC diversity in the world's largest free-ranging population.

    Science.gov (United States)

    Castro-Prieto, Aines; Wachter, Bettina; Sommer, Simone

    2011-04-01

    For more than two decades, the cheetah (Acinonyx jubatus) has been considered a paradigm of disease vulnerability associated with low genetic diversity, particularly at the immune genes of the major histocompatibility complex (MHC). Cheetahs have been used as a classic example in numerous conservation genetics textbooks as well as in many related scientific publications. However, earlier studies used methods with low resolution to quantify MHC diversity and/or small sample sizes. Furthermore, high disease susceptibility was reported only for captive cheetahs, whereas free-ranging cheetahs show no signs of infectious diseases and a good general health status. We examined whether the diversity at MHC class I and class II-DRB loci in 149 Namibian cheetahs was higher than previously reported using single-strand conformation polymorphism analysis, cloning, and sequencing. MHC genes were examined at the genomic and transcriptomic levels. We detected ten MHC class I and four class II-DRB alleles, of which nine MHC class I and all class II-DRB alleles were expressed. Phylogenetic analyses and individual genotypes suggested that the alleles belong to four MHC class I and three class II-DRB putative loci. Evidence of positive selection was detected in both MHC loci. Our study indicated that the low number of MHC class I alleles previously observed in cheetahs was due to a smaller sample size examined. On the other hand, the low number of MHC class II-DRB alleles previously observed in cheetahs was further confirmed. Compared with other mammalian species including felids, cheetahs showed low levels of MHC diversity, but this does not seem to influence the immunocompetence of free-ranging cheetahs in Namibia and contradicts the previous conclusion that the cheetah is a paradigm species of disease vulnerability.

  20. Immunotherapy of MHC class I-deficient tumors

    Czech Academy of Sciences Publication Activity Database

    Reiniš, Milan

    2010-01-01

    Roč. 6, č. 10 (2010), s. 1577-1589 ISSN 1479-6694 R&D Projects: GA ČR GA301/07/1410; GA ČR GAP301/10/2174; GA AV ČR IAA500520807; GA AV ČR IAA500520605 EU Projects: European Commission(XE) 18933 - CLINIGENE Institutional research plan: CEZ:AV0Z50520514 Keywords : tumor vaccine * MHC class I expression * antigen presenting machinery Subject RIV: EB - Genetics ; Molecular Biology Impact factor: 2.455, year: 2010

  1. MHC-DQB1 Variation and Its Association with Resistance or Susceptibility to Cystic Echinococcosis in Chinese Merino Sheep

    Directory of Open Access Journals (Sweden)

    Wenqiao Hui

    2012-12-01

    Full Text Available Cystic echinococcosis (CE, one of the world’s most geographically widespread diseases, still represents a considerable economic and public health significance, although a variety of methods has been used to control the disease. It has been demonstrated that genetic factors, especially variations in MHC loci, can influence the outcome of CE infection in the human population. The study described here was designed to determine whether variation in MHC-DQB1 was associated with susceptibility or resistance to CE in sheep. If so, it would lay a theoretical foundation for breeding disease resistance sheep in future. This study was carried out on 204 Chinese Merino sheep, including 101 CE sheep and 103 healthy controls. The polymorphism of MHC-DQB1 exon 2 was detected by polymerase chain reaction-restriction fragment length polymorphism (PCR-RFLP method, and x2 test was used to compare genotype frequencies between CE sheep and healthy controls. A total of 22 alleles and 42 genotypes were identified in DQB1 exon 2 in Chinese Merino sheep. In addition, x2 test showed that frequencies of DQB1-TaqIaa and DQB1-HaeIIInn genotypes were significantly higher in the healthy group (82.5% and 57.3%, respectively than that in the CE group (57.4% and 28.9%, respectively (both p values = 0, OR = 0.286, 0.303, respectively, suggesting that these genotypes appeared to be associated with resistance to CE. Whereas, frequencies of DQB1-TaqIab and DQB1-HaeIIImn genotypes were significantly higher in the CE group (36.9% and 32.0%, respectively, as compared with the healthy group (16.5% and 11.15%, respectively (p = 0.001, 0.001 and OR = 2.963, 3.629, respectively, indicating that these genotypes might be associated with susceptibility to CE. It is concluded that the genetic polymorphism within MHC-DQB1 might influence immune responses to pathogens, thus leading to the development of CE or protection against CE in Chinese Merino sheep, which would pave the way for breeding

  2. Quantifying the importance of pMHC valency, total pMHC dose and frequency on nanoparticle therapeutic efficacy.

    Science.gov (United States)

    Sugarman, Jordan; Tsai, Sue; Santamaria, Pere; Khadra, Anmar

    2013-05-01

    Nanoparticles (NPs) coated with β-cell-specific peptide major histocompatibility complex (pMHC) class I molecules can effectively restore normoglycemia in spontaneously diabetic nonobese diabetic mice. They do so by expanding pools of cognate memory autoreactive regulatory CD8+ T cells that arise from naive low-avidity T-cell precursors to therapeutic levels. Here we develop our previously constructed mathematical model to explore the effects of compound design parameters (NP dose and pMHC valency) on therapeutic efficacy with the underlying hypothesis that the functional correlates of the therapeutic response (expansion of autoregulatory T cells and deletion of autoantigen-loaded antigen-presenting cells by these T cells) are biphasic. We show, using bifurcation analysis, that the model exhibits a 'resonance'-like behavior for a given range of NP dose in which bistability between the healthy state (possessing zero level of effector T-cell population) and autoimmune state (possessing elevated level of the same population) disappears. A heterogeneous population of model mice subjected to several treatment protocols under these new conditions is conducted to quantify both the average percentage of autoregulatory T cells in responsive and nonresponsive model mice, and the average valency-dependent minimal optimal dose needed for effective therapy. Our results reveal that a moderate increase (≥1.6-fold) in the NP-dependent expansion rate of autoregulatory T-cell population leads to a significant increase in the efficacy and the area corresponding to the effective treatment regimen, provided that NP dose ≥8 μg. We expect the model developed here to generalize to other autoimmune diseases and serve as a computational tool to understand and optimize pMHC-NP-based therapies.

  3. Myocardial gene expression of microRNA-133a and myosin heavy and light chains, in conjunction with clinical parameters, predict regression of left ventricular hypertrophy after valve replacement in patients with aortic stenosis.

    Science.gov (United States)

    Villar, Ana V; Merino, David; Wenner, Mareike; Llano, Miguel; Cobo, Manuel; Montalvo, Cecilia; García, Raquel; Martín-Durán, Rafael; Hurlé, Juan M; Hurlé, María A; Nistal, J Francisco

    2011-07-01

    Left ventricular (LV) reverse remodelling after valve replacement in aortic stenosis (AS) has been classically linked to the hydraulic performance of the replacement device, but myocardial status at the time of surgery has received little attention. To establish predictors of LV mass (LVM) regression 1 year after valve replacement in a surgical cohort of patients with AS based on preoperative clinical and echocardiographic parameters and the myocardial gene expression profile at surgery. Transcript levels of remodelling-related proteins and regulators were determined in LV intraoperative biopsies from 46 patients with AS by RT-PCR. Using multiple linear regression analysis, an equation was developed (adjusted R²=0.73; pregression analysis identified microRNA-133a as a significant positive predictor of LVM normalisation, whereas β-myosin heavy chain and BMI constituted negative predictors. Hypertrophy regression 1 year after pressure overload release is related to the preoperative myocardial expression of remodelling-related genes, in conjunction with the patient's clinical background. In this scenario, miR-133 emerges as a key element of the reverse remodelling process. Postoperative improvement of valve haemodynamics does not predict the degree of hypertrophy regression or LVM normalisation. These results led us to reconsider the current reverse remodelling paradigm and (1) to include criteria of hypertrophy reversibility in the decision algorithm used to decide timing for the operation; and (2) to modify other prevailing factors (overweight, diabetes, etc) known to maintain LV hypertrophy.

  4. The prognostic role of classical and nonclassical MHC class I expression in endometrial cancer

    NARCIS (Netherlands)

    Bijen, C.B.; Bantema-Joppe, E.J.; de Jong, Renske; Leffers, N.; Mourits, M.J.; Eggink, Henk F.; van der Zee, A.G.; Hollema, H.; de Bock, G.H.; Nijman, H.W.

    2010-01-01

    The aim of this study was to investigate classical MHC class I and nonclassical MHC (human leukocyte antigen-G [HLA-GJ) expression in a large cohort of patients with endometrial cancer, to determine the prognostic value of these cell surface markers and their relation with clinicopathological

  5. Social pairing of Seychelles warblers under reduced constraints: MHC, neutral heterozygosity, and age.

    Science.gov (United States)

    Wright, David J; Brouwer, Lyanne; Mannarelli, Maria-Elena; Burke, Terry; Komdeur, Jan; Richardson, David S

    2016-01-01

    The prevalence and significance of precopulatory mate choice remains keenly debated. The major histocompatibility complex (MHC) plays a key role in vertebrate adaptive immunity, and variation at the MHC influences individual survival. Although MHC-dependent mate choice has been documented in certain species, many other studies find no such pattern. This may be, at least in part, because in natural systems constraints may reduce the choices available to individuals and prevent full expression of underlying preferences. We used translocations to previously unoccupied islands to experimentally reduce constraints on female social mate choice in the Seychelles warbler ( Acrocephalus sechellensis ), a species in which patterns of MHC-dependent extrapair paternity (EPP), but not social mate choice, have been observed. We find no evidence of MHC-dependent social mate choice in the new populations. Instead, we find that older males and males with more microsatellite heterozygosity are more likely to have successfully paired. Our data cannot resolve whether these patterns in pairing were due to male-male competition or female choice. However, our research does suggest that female Seychelles warblers do not choose social mates using MHC class I to increase fitness. It may also indicate that the MHC-dependent EPP observed in the source population is probably due to mechanisms other than female precopulatory mate choice based on MHC cues.

  6. NLRC5/MHC class I transactivator is a target for immune evasion in cancer.

    Science.gov (United States)

    Yoshihama, Sayuri; Roszik, Jason; Downs, Isaac; Meissner, Torsten B; Vijayan, Saptha; Chapuy, Bjoern; Sidiq, Tabasum; Shipp, Margaret A; Lizee, Gregory A; Kobayashi, Koichi S

    2016-05-24

    Cancer cells develop under immune surveillance, thus necessitating immune escape for successful growth. Loss of MHC class I expression provides a key immune evasion strategy in many cancers, although the molecular mechanisms remain elusive. MHC class I transactivator (CITA), known as "NLRC5" [NOD-like receptor (NLR) family, caspase recruitment (CARD) domain containing 5], has recently been identified as a critical transcriptional coactivator of MHC class I gene expression. Here we show that the MHC class I transactivation pathway mediated by CITA/NLRC5 constitutes a target for cancer immune evasion. In all the 21 tumor types we examined, NLRC5 expression was highly correlated with the expression of MHC class I, with cytotoxic T-cell markers, and with genes in the MHC class I antigen-presentation pathway, including LMP2/LMP7, TAP1, and β2-microglobulin. Epigenetic and genetic alterations in cancers, including promoter methylation, copy number loss, and somatic mutations, were most prevalent in NLRC5 among all MHC class I-related genes and were associated with the impaired expression of components of the MHC class I pathway. Strikingly, NLRC5 expression was significantly associated with the activation of CD8(+) cytotoxic T cells and patient survival in multiple cancer types. Thus, NLRC5 constitutes a novel prognostic biomarker and potential therapeutic target of cancers.

  7. Ligation of MHC class I molecules on peripheral blood T lymphocytes induces new phenotypes and functions

    DEFF Research Database (Denmark)

    Bregenholt, S; Röpke, M; Skov, S

    1996-01-01

    of T cell-mediated cytotoxicity. Immediately following MHC-I ligation, the T cells responded with increased protein tyrosine phosphorylation, with new bands appearing in the SDS-PAGE. Exposure of T cells to immobilized anti-MHC-I Ab for 24 h induced an increased surface expression of the TCR/CD3 and CD......28 molecules. MHC-I-induced proliferation of purified T cells was dependent on cellular interactions with non-T cells. Under certain conditions, in which MHC-I was ligated by picogram concentrations of immobilized anti-MHC-I Ab, anti-TCR/CD3 Ab-induced proliferation of T cells was strongly inhibited....... These data clearly demonstrate that ligation of the MHC-I complex on T cells may induce both positive and negative signals. Since the physiologic ligands for MHC-I molecules are TCR and the CD8 molecules, our data may suggest that MHC-I molecules are instrumental in cellular interactions between T cells....

  8. The Intensity of Human Body Odors and the MHC: Should We Expect a Link?

    Directory of Open Access Journals (Sweden)

    Claus Wedekind

    2006-01-01

    Full Text Available It is now well established that genes within the major histocompatibility complex (MHC somehow affect the production of body odors in several vertebrates, including humans. Here we discuss whether variation in the intensity of body odors may be influenced by the MHC. In order to examine this question, we have to control for MHC-linked odor perception on the smeller's side. Such a control is necessary because the perception of pleasantness and intensity seem to be confounded, and the causalities are still unsolved. It has previously been found that intense odors are scored as less pleasant if the signaler and the receiver are of MHC-dissimilar type, but not if they are of MHC similar type. We argue, and first data suggest, that an effect of the degree of MHC-heterozygosity and odor intensity is likely (MHC-homozygotes may normally smell more intense, while there is currently no strong argument for other possible links between the MHC and body odor intensity.

  9. Can Selective MHC Downregulation Explain the Specificity and Genetic Diversity of NK Cell Receptors?

    NARCIS (Netherlands)

    Carrillo-Bustamante, Paola; Kesmir, Can; de Boer, Rob J

    2015-01-01

    Natural killer (NK) cells express inhibiting receptors (iNKRs), which specifically bind MHC-I molecules on the surface of healthy cells. When the expression of MHC-I on the cell surface decreases, which might occur during certain viral infections and cancer, iNKRs lose inhibiting signals and the

  10. Fine mapping in the MHC region accounts for 18% additional genetic risk for celiac disease

    NARCIS (Netherlands)

    Gutierrez-Achury, Javier; Zhernakova, Alexandra; Pulit, Sara L.; Trynka, Gosia; Hunt, Karen A.; Romanos, Jihane; Raychaudhuri, Soumya; van Heel, David A.; Wijmenga, Cisca; de Balcker, Paul I. W.

    Although dietary gluten is the trigger for celiac disease, risk is strongly influenced by genetic variation in the major histocompatibility complex (MHC) region. We fine mapped the MHC association signal to identify additional risk factors independent of the HLA-DQA1 and HLA-DQB1 alleles and

  11. Evolution of MHC class I genes in the European badger (Meles meles)

    NARCIS (Netherlands)

    Sin, Yung Wa; Dugdale, Hannah L.; Newman, Chris; Macdonald, David W.; Burke, Terry

    The major histocompatibility complex (MHC) plays a central role in the adaptive immune system and provides a good model with which to understand the evolutionary processes underlying functional genes. Trans-species polymorphism and orthology are both commonly found in MHC genes; however, mammalian

  12. Peptide specific expansion of CD8(+) T cells by recombinant plate bound MHC/peptide complexes

    DEFF Research Database (Denmark)

    Schmidt, Esben G W; Buus, Soren; Thorn, Mette

    2009-01-01

    to in vitro T cell stimulation was investigated. By use of an antigenic peptide derived from the cytomegalovirus (CMVp) we tested the stimulatory efficacy of recombinant plate bound MHC molecules (PB-MHC), being immobilized in culture plates. A single stimulation of non-adherent peripheral blood mononuclear...

  13. MHC Class II and Non-MHC Class II Genes Differentially Influence Humoral Immunity to Bacillus anthracis Lethal Factor and Protective Antigen

    OpenAIRE

    Garman, Lori; Dumas, Eric K.; Kurella, Sridevi; Hunt, Jonathan J.; Crowe, Sherry R.; Nguyen, Melissa L.; Cox, Philip M.; James, Judith A.; Farris, A. Darise

    2012-01-01

    Anthrax Lethal Toxin consists of Protective Antigen (PA) and Lethal Factor (LF), and current vaccination strategies focus on eliciting antibodies to PA. In human vaccination, the response to PA can vary greatly, and the response is often directed toward non-neutralizing epitopes. Variable vaccine responses have been shown to be due in part to genetic differences in individuals, with both MHC class II and other genes playing roles. Here, we investigated the relative contribution of MHC class I...

  14. The Ia.2 Epitope Defines a Subset of Lipid Raft Resident MHC Class II Molecules Crucial to Effective Antigen Presentation1

    Science.gov (United States)

    Busman-Sahay, Kathleen; Sargent, Elizabeth; Harton, Jonathan A.; Drake, James R.

    2016-01-01

    Previous work has established that binding of the 11-5.2 anti-I-Ak mAb, which recognizes the Ia.2 epitope on I-Ak class II molecules, elicits MHC class II signaling, whereas binding of two other anti-I-Ak mAb that recognize the Ia.17 epitope fail to elicit signaling. Using a biochemical approach, we establish that the Ia.2 epitope recognized by the widely used 11-5.2 mAb defines a subset of cell surface I-Ak molecules predominantly found within membrane lipid rafts. Functional studies demonstrate that the Ia.2 bearing subset of I-Ak class II molecules is critically necessary for effective B cell–T cell interactions especially at low antigen doses, a finding consistent with published studies on the role of raft-resident class II molecules in CD4 T cell activation. Interestingly, B cells expressing recombinant I-Ak class II molecules possessing a β chain-tethered HEL peptide lack the Ia.2 epitope and fail to partition into lipid rafts. Moreover, cells expressing Ia.2 negative tethered peptide-class II molecules are severely impaired in their ability to present both tethered peptide or peptide derived from exogenous antigen to CD4 T cells. These results establish the Ia.2 epitope as defining a lipid raft-resident MHC class II confomer vital to the initiation of MHC class II restricted B cell–T cell interactions. PMID:21543648

  15. Population genetic segmentation of MHC-correlated perfume preferences.

    Science.gov (United States)

    Hämmerli, A; Schweisgut, C; Kaegi, M

    2012-04-01

    It has become difficult to find a matching perfume. An overwhelming number of 300 new perfumes launch each year, and marketing campaigns target pre-defined groups based on gender, age or income rather than on individual preferences. Recent evidence for a genetic basis of perfume preferences, however, could be the starting point for a novel population genetic approach to better match perfumes with people's preferences. With a total of 116 participants genotyped for alleles of three loci of the major histocompatibility complex (MHC), the aim of this study was to test whether common MHC alleles could be used as genetic markers to segment a given population into preference types. Significant deviations from random expectations for a set of 10 common perfume ingredients indicate how such segmentation could be achieved. In addition, preference patterns of participants confronted with images that contained a sexual communication context significantly differed in their ratings for some of the scents compared with participants confronted with images of perfume bottles. This strongly supports the assumption that genetically correlated perfume preferences evolved in the context of sexual communication. The results are discussed in the light of perfume customization. © 2011 The Authors. ICS © 2011 Society of Cosmetic Scientists and the Société Française de Cosmétologie.

  16. Porcine major histocompatibility complex (MHC) class I molecules and analysis of their peptide-binding specificities

    DEFF Research Database (Denmark)

    Pedersen, Lasse Eggers; Harndahl, Mikkel; Rasmussen, Michael

    2011-01-01

    a HLA-I molecule (HLA-A*11:01), thereby generating recombinant human/swine chimeric MHC-I molecules as well as the intact SLA-1*0401 molecule. Biochemical peptide-binding assays and positional scanning combinatorial peptide libraries were used to analyze the peptide-binding motifs of these molecules....... A pan-specific predictor of peptide–MHC-I binding, NetMHCpan, which was originally developed to cover the binding specificities of all known HLA-I molecules, was successfully used to predict the specificities of the SLA-1*0401 molecule as well as the porcine/human chimeric MHC-I molecules. These data......In all vertebrate animals, CD8+ cytotoxic T lymphocytes (CTLs) are controlled by major histocompatibility complex class I (MHC-I) molecules. These are highly polymorphic peptide receptors selecting and presenting endogenously derived epitopes to circulating CTLs. The polymorphism of the MHC...

  17. Gapped sequence alignment using artificial neural networks: application to the MHC class I system

    DEFF Research Database (Denmark)

    Andreatta, Massimo; Nielsen, Morten

    2016-01-01

    . On this relatively simple system, we developed a sequence alignment method based on artificial neural networks that allows insertions and deletions in the alignment. Results: We show that prediction methods based on alignments that include insertions and deletions have significantly higher performance than methods...... trained on peptides of single lengths. Also, we illustrate how the location of deletions can aid the interpretation of the modes of binding of the peptide-MHC, as in the case of long peptides bulging out of the MHC groove or protruding at either terminus. Finally, we demonstrate that the method can learn...... the length profile of different MHC molecules, and quantified the reduction of the experimental effort required to identify potential epitopes using our prediction algorithm. Availability and implementation: The NetMHC-4.0 method for the prediction of peptide-MHC class I binding affinity using gapped...

  18. MHC class II+ (HLA-DP-like) cells in the cow reproductive tract: II. Immunolocalization of MHC class II+ cells in oviduct and vagina.

    Science.gov (United States)

    Eren, U; Kum, S; Sandikçi, M; Eren, V; Ilhan, F

    2009-08-01

    The aim of this study was to determine and examine the distribution of major frequency MHC II+ cells in the oviduct and vagina of cows during the oestrous and dioestrus phases. Right oviduct (ampulla, isthmus) and vaginal samples taken from a total of twenty seven multiparous cows were used. Tissue samples were processed to obtain both cryostat and paraffin sections. Sections were stained immunocytochemically using StreptABC method using a specific monoclonal antibody to MHC II+ cell population. Intra-epithelial and subepithelial areas along with lamina propria, muscularis mucosae and serosa of both ampulla and isthmus and intra-epithelial/subepithelial areas and mucosae of vagina were examined for the presence of MHC II+ cells. The density of immune positive cells was determined using a subjective scoring system. MHC II+ cells were demonstrated in all areas examined in both oestrus and dioestrus. In oestrus, the density of MHC II+ cells decreased in subepithelial areas (in between the epithelial cells and the basal membrane) of isthmus, whereas the density of immune positive cells was increased in muscularis mucosae of isthmus (P < 0.05), lamina propria and muscularis mucosae of ampulla (P < 0.05) as well as in the mucosae of vagina (P MHC II+ cells observed in the oviduct and vagina increases in the majority of areas examined due to the effect of oestrogen.

  19. TLR signals induce phagosomal MHC-I delivery from the endosomal recycling compartment to allow cross-presentation

    NARCIS (Netherlands)

    Nair-Gupta, Priyanka; Baccarini, Alessia; Tung, Navpreet; Seyffer, Fabian; Florey, Oliver; Huang, Yunjie; Banerjee, Meenakshi; Overholtzer, Michael; Roche, Paul A.; Tampé, Robert; Brown, Brian D.; Amsen, Derk; Whiteheart, Sidney W.; Blander, J. Magarian

    2014-01-01

    Adaptation of the endoplasmic reticulum (ER) pathway for MHC class I (MHC-I) presentation in dendritic cells enables cross-presentation of peptides derived from phagocytosed microbes, infected cells, or tumor cells to CD8 T cells. How these peptides intersect with MHC-I molecules remains poorly

  20. Antibody Stabilization of Peptide–MHC Multimers Reveals Functional T Cells Bearing Extremely Low-Affinity TCRs

    DEFF Research Database (Denmark)

    Tungatt, Katie; Bianchi, Valentina; Crowther, Michael D

    2015-01-01

    Fluorochrome-conjugated peptide-MHC (pMHC) multimers are commonly used in combination with flow cytometry for direct ex vivo visualization and characterization of Ag-specific T cells, but these reagents can fail to stain cells when TCR affinity and/or TCR cell-surface density are low. pMHC multim...

  1. Gene transfer preferentially selects MHC class I positive tumour cells and enhances tumour immunogenicity.

    Science.gov (United States)

    Hacker, Ulrich T; Schildhauer, Ines; Barroso, Margarita Céspedes; Kofler, David M; Gerner, Franz M; Mysliwietz, Josef; Buening, Hildegard; Hallek, Michael; King, Susan B S

    2006-05-01

    The modulated expression of MHC class I on tumour tissue is well documented. Although the effect of MHC class I expression on the tumorigenicity and immunogenicity of MHC class I negative tumour cell lines has been rigorously studied, less is known about the validity of gene transfer and selection in cell lines with a mixed MHC class I phenotype. To address this issue we identified a C26 cell subline that consists of distinct populations of MHC class I (H-2D/K) positive and negative cells. Transient transfection experiments using liposome-based transfer showed a lower transgene expression in MHC class I negative cells. In addition, MHC class I negative cells were more sensitive to antibiotic selection. This led to the generation of fully MHC class I positive cell lines. In contrast to C26 cells, all transfectants were rejected in vivo and induced protection against the parental tumour cells in rechallenge experiments. Tumour cell specificity of the immune response was demonstrated in in vitro cytokine secretion and cytotoxicity assays. Transfectants expressing CD40 ligand and hygromycin phosphotransferase were not more immunogenic than cells expressing hygromycin resistance alone. We suggest that the MHC class I positive phenotype of the C26 transfectants had a bearing on their immunogenicity, because selected MHC class I positive cells were more immunogenic than parental C26 cells and could induce specific anti-tumour immune responses. These data demonstrate that the generation of tumour cell transfectants can lead to the selection of subpopulations that show an altered phenotype compared to the parental cell line and display altered immunogenicity independent of selection marker genes or other immune modulatory genes. Our results show the importance of monitoring gene transfer in the whole tumour cell population, especially for the evaluation of in vivo therapies targeted to heterogeneous tumour cell populations.

  2. H pylori receptor MHC class II contributes to the dynamic gastric epithelial apoptotic response

    Science.gov (United States)

    Bland, David A; Suarez, Giovanni; Beswick, Ellen J; Sierra, Johanna C; Reyes, Victor E

    2006-01-01

    AIM: To investigate the role of MHC class II in the modulation of gastric epithelial cell apoptosis induced by H pylori infection. METHODS: After stimulating a human gastric epithelial cell line with bacteria or agonist antibodies specific for MHC class II and CD95, the quantitation of apoptotic and anti-apoptotic events, including caspase activation, BCL-2 activation, and FADD recruitment, was performed with a fluorometric assay, a cytometric bead array, and confocal microscopy, respectively. RESULTS: Pretreatment of N87 cells with the anti-MHC class II IgM antibody RFD1 resulted in a reduction in global caspase activation at 24 h of H pylori infection. When caspase 3 activation was specifically measured, crosslinking of MHC class II resulted in a marked reduced caspase activation, while simple ligation of MHC class II did not. Crosslinking of MHC class II also resulted in an increased activation of the anti-apoptosis molecule BCL-2 compared to simple ligation. Confocal microscope analysis demonstrated that the pretreatment of gastric epithelial cells with a crosslinking anti-MHC class II IgM blocked the recruitment of FADD to the cell surface. CONCLUSION: The results presented here demonstrate that the ability of MHC class II to modulate gastric epithelial apoptosis is at least partially dependent on its crosslinking. Furthermore, while previous research has demonstrated that MHC class II signaling can be pro-apoptotic during extended ligation, we have shown that the crosslinking of this molecule has anti-apoptotic effects during the earlier time points of H pylori infection. This effect is possibly mediated by the ability of MHC class II to modulate the activation of the pro-apoptotic receptor Fas by blocking the recruitment of the accessory molecule FADD, and this delay in apoptosis induction could allow for prolonged cytokine secretion by H pylori-infected gastric epithelial cells. PMID:16981259

  3. MHC Intratumoral Heterogeneity May Predict Cancer Progression and Response to Immunotherapy

    Directory of Open Access Journals (Sweden)

    Irene Romero

    2018-01-01

    Full Text Available An individual tumor can present intratumoral phenotypic heterogeneity, containing tumor cells with different phenotypes that do not present irreversible genetic alterations. We have developed a mouse cancer model, named GR9, derived from a methylcholanthrene-induced fibrosarcoma that was adapted to tissue culture and cloned into different tumor cell lines. The clones showed diverse MHC-I phenotypes, ranging from highly positive to weakly positive MHC-I expression. These MHC-I alterations are due to reversible molecular mechanisms, because surface MHC-I could be recovered by IFN-γ treatment. Cell clones with high MHC-I expression demonstrated low local oncogenicity and high spontaneous metastatic capacity, whereas MHC-I-low clones showed high local oncogenicity and no spontaneous metastatic capacity. Although MHC-I-low clones did not metastasize, they produced MHC-I-positive dormant micrometastases controlled by the host immune system, i.e., in a state of immunodormancy. The metastatic capacity of each clone was directly correlated with the host T-cell subpopulations; thus, a strong decrease in cytotoxic and helper T lymphocytes was observed in mice with numerous metastases derived from MHC-I positive tumor clones but a strong increase was observed in those with dormant micrometastases. Immunotherapy was administered to the hosts after excision of the primary tumor, producing a recovery in their immune status and leading to the complete eradication of overt spontaneous metastases or their decrease. According to these findings, the combination of MHC-I surface expression in primary tumor and metastases with host T-cell subsets may be a decisive indicator of the clinical outcome and response to immunotherapy in metastatic disease, allowing the identification of responders to this approach.

  4. ER stress affects processing of MHC class I-associated peptides

    Directory of Open Access Journals (Sweden)

    Meloche Sylvain

    2009-02-01

    Full Text Available Abstract Background Viral infection and neoplastic transformation trigger endoplasmic reticulum (ER stress. Thus, a large proportion of the cells that must be recognized by the immune system are stressed cells. Cells respond to ER stress by launching the unfolded protein response (UPR. The UPR regulates the two key processes that control major histocompatibility complex class I (MHC I-peptide presentation: protein synthesis and degradation. We therefore asked whether and how the UPR impinges on MHC I-peptide presentation. Results We evaluated the impact of the UPR on global MHC I expression and on presentation of the H2Kb-associated SIINFEKL peptide. EL4 cells stably transfected with vectors coding hen egg lysozyme (HEL-SIINFEKL protein variants were stressed with palmitate or exposed to glucose deprivation. UPR decreased surface expression of MHC I but did not affect MHC I mRNA level nor the total amount of intracellular MHC I proteins. Impaired MHC I-peptide presentation was due mainly to reduced supply of peptides owing to an inhibition of overall protein synthesis. Consequently, generation of H2Kb-SIINFEKL complexes was curtailed during ER stress, illustrating how generation of MHC I peptide ligands is tightly coupled to ongoing protein synthesis. Notably, the UPR-induced decline of MHC I-peptide presentation was more severe when the protein source of peptides was localized in the cytosol than in the ER. This difference was not due to changes in the translation rates of the precursor proteins but to increased stability of the cytosolic protein during ER stress. Conclusion Our results demonstrate that ER stress impairs MHC I-peptide presentation, and that it differentially regulates expression of ER- vs. cytosol-derived peptides. Furthermore, this work illustrates how ER stress, a typical feature of infected and malignant cells, can impinge on cues for adaptive immune recognition.

  5. MHC class II-derived peptides can bind to class II molecules, including self molecules, and prevent antigen presentation

    DEFF Research Database (Denmark)

    Rosloniec, E F; Vitez, L J; Buus, S

    1990-01-01

    the alpha k-3 peptide binds slightly less well. These combined data, suggesting that class II-derived peptides can bind to MHC class II molecules, including the autologous molecule from which they are derived, have important implications for the molecular basis of alloreactivity and autoreactivity. Further...... found in the first and third polymorphic regions (PMR) of the A alpha k chain (alpha k-1 and alpha k-3) were capable of inhibiting the presentation of three different HEL-derived peptide antigens to their appropriate T cells. In addition, the alpha k-1 peptide inhibited the presentation of the OVA(323......-339) immunodominant peptide to the I-Ad-restricted T cell hybridomas specific for it. Prepulsing experiments demonstrated that the PMR peptides were interacting with the APC and not with the T cell hybridomas. These observations were confirmed and extended by the demonstration that the alpha k-1 and alpha k-3...

  6. MHC class I chain-related A: Polymorphism, regulation and therapeutic value in cancer.

    Science.gov (United States)

    Yang, Xi; Kuang, Shuzhen; Wang, Liangjiang; Wei, Yanzhang

    2018-07-01

    MICA and MICB are stress-induced molecules recognized by NKG2D, one of major activation receptors of natural killer (NK) cells. Upon binding to NKG2D, NKG2D-mediated cytolytic immune response of immune effector cells will be activated against virally infected and tumor cells expressing MICA. In the early oncogenic development, membrane-bound MICA serves as a key signal to recruit anti-tumor immune effectors. Nevertheless, both MICA polymorphic features and its dysregulated expression in evolving tumors have resulted in tumor evasion in various cancer types. Therefore, in order to reconstitute tumor immunosurveilance, it is of great significance that we understand MICA genetics, polymorphisms, mechanisms of MICA-associated tumor escape and molecular/cellular modulation of MICA. In this review, the MICA-associated co-expression networks involving microRNAs (miRNAs) and novel candidate long non-coding RNAs (lncRNAs) were also discussed. Given the current importance in the study of MICA gene, this review paper focuses on the role of MICA in different cancer types, and strategies that we manipulate MICA regulation against tumor proliferation. Copyright © 2018. Published by Elsevier Masson SAS.

  7. Major histocompatibility complex (MHC) class III genetics in two Amerindian tribes from southern Brazil: the Kaingang and the Guarani.

    Science.gov (United States)

    Weg-Remers, S; Brenden, M; Schwarz, E; Witzel, K; Schneider, P M; Guerra, L K; Rehfeldt, I R; Lima, M T; Hartmann, D; Petzl-Erler, M L; de Messias, I J; Mauff, G

    1997-10-01

    Population genetic studies of the major histocompatibility complex (MHC) class III region, comprising C2, BF and C4 phenotypes, and molecular genetic data are rarely available for populations other than Caucasoids. We have investigated three Amerindian populations from Southern Brazil: 131 Kaingang from Ivaí (KIV), 111 Kaingang (KRC) and 100 Guarani (GRC) from Rio das Cobras. Extended MHC haplotypes were derived after standard C2, BF, C4 phenotyping and restriction fragment length polymorphism (RFLP) analysis with TaqI, together with HLA data published previously by segregation analysis. C2 and BF frequencies corresponded to other Amerindian populations. C4B*Q0 frequency was high in the GRC (0.429) but low in the Kaingang. Unusual C4 alleles were found, viz. C4A*58, A*55 and C4B*22 (presumably non-Amerindian) and aberrant C4A*3 of Amerindian origin occurring with a frequency of 0.223 in the GRC. C4A*3 bands of homo- and heterozygous individuals carrying this variant were Rodgers 1 positive and Chido 1,3 positive, showed a C4A specific lysis type and a C4A like alpha-chain. Polymerase chain reaction studies and sequencing showed that this is based on a C4A*3 duplication with a regular C4A*3 and a partially converted C4A*0304 carrying the C4B specific epitopes Ch 6 and Ch 1,3. Associations of class III haplotypes with particular RFLP patterns were similar to those reported for Caucasoids. The previously described association between combined C4A and CYP21P deletions and the 6.4 kb TaqI fragment was not seen in these Amerindians. This fragment occurred within a regular two locus gene structure in the Kaingang, representing a "short" gene at C4 locus I. C4 and CYP21 duplications were frequently observed. The distribution of extended MHC haplotypes provides evidence for a close relationship between the KIV and KRC and a larger genetic distance between the two Kaingang groups and the GRC.

  8. The Glycosylphosphatidylinositol-Anchored Variable Region of Llama Heavy Chain-Only Antibody JM4 Efficiently Blocks both Cell-Free and T Cell-T Cell Transmission of Human Immunodeficiency Virus Type 1.

    Science.gov (United States)

    Liu, Lihong; Wang, Weiming; Matz, Julie; Ye, Chaobaihui; Bracq, Lucie; Delon, Jerome; Kimata, Jason T; Chen, Zhiwei; Benichou, Serge; Zhou, Paul

    2016-12-01

    The variable regions (VHHs) of two heavy chain-only antibodies, JM2 and JM4, from llamas that have been immunized with a trimeric gp140 bound to a CD4 mimic have been recently isolated (here referred to as VHH JM2 and VHH JM4, respectively). JM2 binds the CD4-binding site of gp120 and neutralizes HIV-1 strains from subtypes B, C, and G. JM4 binds gp120 and neutralizes HIV-1 strains from subtypes A, B, C, A/E, and G in a CD4-dependent manner. In the present study, we constructed glycosylphosphatidylinositol (GPI)-anchored VHH JM2 and JM4 along with an E4 control and transduced them into human CD4 + cell lines and primary CD4 T cells. We report that by genetically linking the VHHs with a GPI attachment signal, VHHs are targeted to the lipid rafts of the plasma membranes. Expression of GPI-VHH JM4, but not GPI-VHH E4 and JM2, on the surface of transduced TZM.bl cells potently neutralizes multiple subtypes of HIV-1 isolates, including tier 2 or 3 strains, transmitted founders, quasispecies, and soluble single domain antibody (sdAb) JM4-resistant viruses. Moreover, transduction of CEMss-CCR5 cells with GPI-VHH JM4, but not with GPI-VHH E4, confers resistance to both cell-free and T cell-T cell transmission of HIV-1 and HIV-1 envelope-mediated fusion. Finally, GPI-VHH JM4-transduced human primary CD4 T cells efficiently resist both cell-free and T cell-T cell transmission of HIV-1. Thus, we conclude that VHH JM4, when targeted to the lipid rafts of the plasma membrane, efficiently neutralizes HIV-1 infection via both cell-free and T cell-T cell transmission. Our findings should have important implications for GPI-anchored antibody-based therapy against HIV-1. Lipid rafts are specialized dynamic microdomains of the plasma membrane and have been shown to be gateways for HIV-1 budding as well as entry into T cells and macrophages. In nature, many glycosylphosphatidylinositol (GPI)-anchored proteins localize in the lipid rafts. In the present study, we developed GPI

  9. Virus encoded MHC-like decoys diversify the inhibitory KIR repertoire.

    Directory of Open Access Journals (Sweden)

    Paola Carrillo-Bustamante

    Full Text Available Natural killer (NK cells are circulating lymphocytes that play an important role in the control of viral infections and tumors. Their functions are regulated by several activating and inhibitory receptors. A subset of these receptors in human NK cells are the killer immunoglobulin-like receptors (KIRs, which interact with the highly polymorphic MHC class I molecules. One important function of NK cells is to detect cells that have down-regulated MHC expression (missing-self. Because MHC molecules have non polymorphic regions, their expression could have been monitored with a limited set of monomorphic receptors. Surprisingly, the KIR family has a remarkable genetic diversity, the function of which remains poorly understood. The mouse cytomegalovirus (MCMV is able to evade NK cell responses by coding "decoy" molecules that mimic MHC class I. This interaction was suggested to have driven the evolution of novel NK cell receptors. Inspired by the MCMV system, we develop an agent-based model of a host population infected with viruses that are able to evolve MHC down-regulation and decoy molecules. Our simulations show that specific recognition of MHC class I molecules by inhibitory KIRs provides excellent protection against viruses evolving decoys, and that the diversity of inhibitory KIRs will subsequently evolve as a result of the required discrimination between host MHC molecules and decoy molecules.

  10. Protective influences on experimental autoimmune encephalomyelitis by MHC class I and class II alleles

    DEFF Research Database (Denmark)

    Mustafa, M; Vingsbo, C; Olsson, T

    1994-01-01

    are resistant. Interestingly, rats with the MHC u haplotype develop an immune response to the MBP 63-88, but do not get EAE. In this study we have used intra-MHC recombinant rat strains to compare the influences of the MHC u with the a haplotype. We discovered the following: 1) The class II region of the MHC...... a haplotype permits EAE and a Th1 type of immune response as measured by IFN-gamma production after in vitro challenge of in vivo-primed T cells with MBP 63-88. 2) The class II region of the u haplotype is associated with a disease-protective immune response characterized by production of not only IFN......Experimental autoimmune encephalomyelitis (EAE) is influenced by polymorphism of the MHC. We have previously found that Lewis rats with certain MHC haplotypes are susceptible to disease induced with the myelin basic protein (MBP) peptide 63-88, whereas Lewis rats with other MHC haplotypes...

  11. Orf virus interferes with MHC class I surface expression by targeting vesicular transport and Golgi

    Directory of Open Access Journals (Sweden)

    Rohde Jörg

    2012-07-01

    Full Text Available Abstract Background The Orf virus (ORFV, a zoonotic Parapoxvirus, causes pustular skin lesions in small ruminants (goat and sheep. Intriguingly, ORFV can repeatedly infect its host, despite the induction of a specific immunity. These immune modulating and immune evading properties are still unexplained. Results Here, we describe that ORFV infection of permissive cells impairs the intracellular transport of MHC class I molecules (MHC I as a result of structural disruption and fragmentation of the Golgi apparatus. Depending on the duration of infection, we observed a pronounced co-localization of MHC I and COP-I vesicular structures as well as a reduction of MHC I surface expression of up to 50%. These subversion processes are associated with early ORFV gene expression and are accompanied by disturbed carbohydrate trimming of post-ER MHC I. The MHC I population remaining on the cell surface shows an extended half-life, an effect that might be partially controlled also by late ORFV genes. Conclusions The presented data demonstrate that ORFV down-regulates MHC I surface expression in infected cells by targeting the late vesicular export machinery and the structure and function of the Golgi apparatus, which might aid to escape cellular immune recognition.

  12. Disentangling the roles of natural selection and genetic drift in shaping variation at MHC immunity genes.

    Science.gov (United States)

    Sutton, Jolene T; Nakagawa, Shinichi; Robertson, Bruce C; Jamieson, Ian G

    2011-11-01

    The major histocompatibility complex (MHC) forms an integral component of the vertebrate immune response and, due to strong selection pressures, is one of the most polymorphic regions of the entire genome. Despite over 15 years of research, empirical studies offer highly contradictory explanations of the relative roles of different evolutionary forces, selection and genetic drift, acting on MHC genes during population bottlenecks. Here, we take a meta-analytical approach to quantify the results of studies into the effects of bottlenecks on MHC polymorphism. We show that the consequences of selection acting on MHC loci prior to a bottleneck event, combined with drift during the bottleneck, will result in overall loss of MHC polymorphism that is ∼15% greater than loss of neutral genetic diversity. These results are counter to general expectations that selection should maintain MHC polymorphism, but do agree with the results of recent simulation models and at least two empirical studies. Notably, our results suggest that negative frequency-dependent selection could be more important than overdominance for maintaining high MHC polymorphism in pre-bottlenecked populations. © 2011 Blackwell Publishing Ltd.

  13. Peptide and Peptide-Dependent Motions in MHC Proteins: Immunological Implications and Biophysical Underpinnings

    Directory of Open Access Journals (Sweden)

    Cory M. Ayres

    2017-08-01

    Full Text Available Structural biology of peptides presented by class I and class II MHC proteins has transformed immunology, impacting our understanding of fundamental immune mechanisms and allowing researchers to rationalize immunogenicity and design novel vaccines. However, proteins are not static structures as often inferred from crystallographic structures. Their components move and breathe individually and collectively over a range of timescales. Peptides bound within MHC peptide-binding grooves are no exception and their motions have been shown to impact recognition by T cell and other receptors in ways that influence function. Furthermore, peptides tune the motions of MHC proteins themselves, which impacts recognition of peptide/MHC complexes by other proteins. Here, we review the motional properties of peptides in MHC binding grooves and discuss how peptide properties can influence MHC motions. We briefly review theoretical concepts about protein motion and highlight key data that illustrate immunological consequences. We focus primarily on class I systems due to greater availability of data, but segue into class II systems as the concepts and consequences overlap. We suggest that characterization of the dynamic “energy landscapes” of peptide/MHC complexes and the resulting functional consequences is one of the next frontiers in structural immunology.

  14. MHC class II molecules regulate growth in human T cells

    DEFF Research Database (Denmark)

    Nielsen, M; Odum, Niels; Bendtzen, K

    1994-01-01

    MHC-class-II-positive T cells are found in tissues involved in autoimmune disorders. Stimulation of class II molecules by monoclonal antibodies (mAbs) or bacterial superantigens induces protein tyrosine phosphorylation through activation of protein tyrosine kinases in T cells, and class II signals...... lines tested. Only one of three CD4+, CD45RAhigh, ROhigh T cells responded to class II costimulation. There was no correlation between T cell responsiveness to class II and the cytokine production profile of the T cell in question. Thus, T cell lines producing interferon (IFN)-gamma but not IL-4 (TH1...... modulate several T cell responses. Here, we studied further the role of class II molecules in the regulation of T cell growth. Costimulation of class II molecules by immobilized HLA-DR mAb significantly enhanced interleukin (IL)-2-supported T cell growth of the majority of CD4+, CD45RAlow, ROhigh T cell...

  15. Increased cardiac alpha-myosin heavy chain in left atria and decreased myocardial insulin-like growth factor (Igf-I) expression accompany low heart rate in hibernating grizzly bears.

    Science.gov (United States)

    Barrows, N D; Nelson, O L; Robbins, C T; Rourke, B C

    2011-01-01

    Grizzly bears (Ursus arctos horribilis) tolerate extended periods of extremely low heart rate during hibernation without developing congestive heart failure or cardiac chamber dilation. Left ventricular atrophy and decreased left ventricular compliance have been reported in this species during hibernation. We evaluated the myocardial response to significantly reduced heart rate during hibernation by measuring relative myosin heavy-chain (MyHC) isoform expression and expression of a set of genes important to muscle plasticity and mass regulation in the left atria and left ventricles of active and hibernating bears. We supplemented these data with measurements of systolic and diastolic function via echocardiography in unanesthetized grizzly bears. Atrial strain imaging revealed decreased atrial contractility, decreased expansion/reservoir function (increased atrial stiffness), and decreased passive-filling function (increased ventricular stiffness) in hibernating bears. Relative MyHC-α protein expression increased significantly in the atrium during hibernation. The left ventricle expressed 100% MyHC-β protein in both groups. Insulin-like growth factor (IGF-I) mRNA expression was reduced by ∼50% in both chambers during hibernation, consistent with the ventricular atrophy observed in these bears. Interestingly, mRNA expression of the atrophy-related ubiquitin ligases Muscle Atrophy F-box (MAFBx) and Muscle Ring Finger 1 did not increase, nor did expression of myostatin or hypoxia-inducible factor 1α (HIF-1α). We report atrium-specific decreases of 40% and 50%, respectively, in MAFBx and creatine kinase mRNA expression during hibernation. Decreased creatine kinase expression is consistent with lowered energy requirements and could relate to reduced atrial emptying function during hibernation. Taken together with our hemodynamic assessment, these data suggest a potential downregulation of atrial chamber function during hibernation to prevent fatigue and dilation

  16. Proportions of myosin heavy chain mRNAs, protein isoforms and fiber types in the slow and fast skeletal muscles are maintained after alterations of thyroid status in rats.

    Science.gov (United States)

    Soukup, T; Diallo, M

    2015-01-01

    Recently, we have established that slow soleus (SOL) and fast extensor digitorum longus (EDL) muscles of euthyroid (EU) Lewis rats posses the same proportions between their four myosin heavy chain (MyHC) mRNAs, protein isoforms and fiber types as determined by real time RT-PCR, SDS-PAGE and 2-D stereological fiber type analysis, respectively. In the present paper we investigated if these proportions are maintained in adult Lewis rats with hyperthyroid (HT) and hypothyroid (HY) status. Although HT and HY states change MyHC isoform expression, results from all three methods showed that proportion between MyHC mRNA-1, 2a, -2x/d, -2b, protein isoforms MyHC-1, -2a, -2x/d, -2b and to lesser extent also fiber types 1, 2A, 2X/D, 2B were preserved in both SOL and EDL muscles. Furthermore, in the SOL muscle mRNA expression of slow MyHC-1 remained up to three orders higher compared to fast MyHC transcripts, which explains the predominance of MyHC-1 isoform and fiber type 1 even in HT rats. Although HT status led in the SOL to increased expression of MyHC-2a mRNA, MyHC-2a isoform and 2A fibers, it preserved extremely low expression of MyHC-2x and -2b mRNA and protein isoforms, which explains the absence of pure 2X/D and 2B fibers. HY status, on the other hand, almost completely abolished expression of all three fast MyHC mRNAs, MyHC protein isoforms and fast fiber types in the SOL muscle. Our data present evidence that a correlation between mRNA, protein content and fiber type composition found in EU status is also preserved in HT and HY rats.

  17. Stimulatory and inhibitory mechanisms of slow muscle-specific myosin heavy chain gene expression in fish: Transient and transgenic analysis of torafugu MYHM86-2 promoter in zebrafish embryos

    International Nuclear Information System (INIS)

    Asaduzzaman, Md.; Kinoshita, Shigeharu; Bhuiyan, Sharmin Siddique; Asakawa, Shuichi; Watabe, Shugo

    2013-01-01

    The myosin heavy chain gene, MYH M86-2 , exhibited restricted expression in slow muscle fibers of torafugu embryos and larvae, suggesting its functional roles for embryonic and larval muscle development. However, the transcriptional mechanisms involved in its expression are still ambiguous. The present study is the first extensive analysis of slow muscle-specific MYH M86-2 promoter in fish for identifying the cis-elements that are crucial for its expression. Combining both transient transfection and transgenic approaches, we demonstrated that the 2614 bp 5′-flanking sequences of MYH M86-2 contain a sufficient promoter activity to drive gene expression specific to superficial slow muscle fibers. By cyclopamine treatment, we also demonstrated that the differentiation of such superficial slow muscle fibers depends on hedgehog signaling activity. The deletion analyses defined an upstream fragment necessary for repressing ectopic MYH M86-2 expression in the fast muscle fibers. The transcriptional mechanism that prevents MYH M86-2 expression in the fast muscle fibers is mediated through Sox6 binding elements. We also demonstrated that Sox6 may function as a transcriptional repressor of MYH M86-2 expression. We further discovered that nuclear factor of activated T cells (NFAT) binding elements plays a key role and myocyte enhancer factor-2 (MEF2) binding elements participate in the transcriptional regulation of MYH M86-2 expression. - Highlights: ► MYH M86-2 is highly expressed in slow muscle fibers of torafugu embryos and larvae. ► MYH M86-2 promoter activity depends on the hedgehog signaling. ► Sox6 binding elements inhibits MYH M86-2 expression in fast muscle fibers. ► Sox6 elements function as transcriptional repressor of MYH M86-2 promoter activity. ► NFAT and MEF2 binding elements play a key role for directing MYH M86-2 expression

  18. A Novel Alpha Cardiac Actin (ACTC1 Mutation Mapping to a Domain in Close Contact with Myosin Heavy Chain Leads to a Variety of Congenital Heart Defects, Arrhythmia and Possibly Midline Defects.

    Directory of Open Access Journals (Sweden)

    Céline Augière

    Full Text Available A Lebanese Maronite family presented with 13 relatives affected by various congenital heart defects (mainly atrial septal defects, conduction tissue anomalies and midline defects. No mutations were found in GATA4 and NKX2-5.A set of 399 poly(AC markers was used to perform a linkage analysis which peaked at a 2.98 lod score on the long arm of chromosome 15. The haplotype analysis delineated a 7.7 meganucleotides genomic interval which included the alpha-cardiac actin gene (ACTC1 among 36 other protein coding genes. A heterozygous missense mutation was found (c.251T>C, p.(Met84Thr in the ACTC1 gene which changed a methionine residue conserved up to yeast. This mutation was absent from 1000 genomes and exome variant server database but segregated perfectly in this family with the affection status. This mutation and 2 other ACTC1 mutations (p.(Glu101Lys and p.(Met125Val which result also in congenital heart defects are located in a region in close apposition to a myosin heavy chain head region by contrast to 3 other alpha-cardiac actin mutations (p.(Ala297Ser,p.(Asp313His and p.(Arg314His which result in diverse cardiomyopathies and are located in a totally different interaction surface.Alpha-cardiac actin mutations lead to congenital heart defects, cardiomyopathies and eventually midline defects. The consequence of an ACTC1 mutation may in part be dependent on the interaction surface between actin and myosin.

  19. Comparison of immune responses against foot-and-mouth disease virus induced by fusion proteins using the swine IgG heavy chain constant region or β-galactosidase as a carrier of immunogenic epitopes

    International Nuclear Information System (INIS)

    Li Guangjin; Chen Weizao; Yan Weiyao; Zhao Kai; Liu Mingqiu; Zhang Jun; Fei Liang; Xu Quanxing; Sheng Zutian; Lu Yonggan; Zheng Zhaoxin

    2004-01-01

    Previously, we demonstrated that a fusion protein (Gal-FMDV) consisting of β-galactosidase and an immunogenic peptide, amino acids (141-160)-(21-40)-(141-160), of foot-and-mouth disease virus (FMDV) VP1 protein induced protective immune responses in guinea pigs and swine. We now designed a new potential recombinant protein vaccine against FMDV in swine. The immunogenic peptide, amino acids (141-160)-(21-40)-(141-160) from the VP1 protein of serotype O FMDV, was fused to the carboxy terminus of a swine immunoglobulin G single heavy chain constant region and expressed in Escherichia coli. The expressed fusion protein (IgG-FMDV) was purified and emulsified with oil adjuvant. Vaccination twice at an interval of 3 weeks with the emulsified IgG-FMDV fusion protein induced an FMDV-specific spleen proliferative T-cell response in guinea pigs and elicited high levels of neutralizing antibody in guinea pigs and swine. All of the immunized animals were efficiently protected against FMDV challenge. There was no significant difference between IgG-FMDV and Gal-FMDV in eliciting immunity after vaccination twice in swine. However, when evaluating the efficacy of a single inoculation of the fusion proteins, we found that IgG-FMDV could elicit a protective immune response in swine, while Gal-FMDV only elicited a weak neutralizing activity and could not protect the swine against FMDV challenge. Our results suggest that the IgG-FMDV fusion protein is a promising vaccine candidate for FMD in swine

  20. Natural selection on MHC IIβ in parapatric lake and stream stickleback: Balancing, divergent, both or neither?

    Science.gov (United States)

    Stutz, William E; Bolnick, Daniel I

    2017-09-01

    Major histocompatibility complex (MHC) genes encode proteins that play a central role in vertebrates' adaptive immunity to parasites. MHC loci are among the most polymorphic in vertebrates' genomes, inspiring many studies to identify evolutionary processes driving MHC polymorphism within populations and divergence between populations. Leading hypotheses include balancing selection favouring rare alleles within populations, and spatially divergent selection. These hypotheses do not always produce diagnosably distinct predictions, causing many studies of MHC to yield inconsistent or ambiguous results. We suggest a novel strategy to distinguish balancing vs. divergent selection on MHC, taking advantage of natural admixture between parapatric populations. With divergent selection, individuals with immigrant alleles will be more infected and less fit because they are susceptible to novel parasites in their new habitat. With balancing selection, individuals with locally rare immigrant alleles will be more fit (less infected). We tested these contrasting predictions using three-spine stickleback from three replicate pairs of parapatric lake and stream habitats. We found numerous positive and negative associations between particular MHC IIβ alleles and particular parasite taxa. A few allele-parasite comparisons supported balancing selection, and others supported divergent selection between habitats. But, there was no overall tendency for fish with immigrant MHC alleles to be more or less heavily infected. Instead, locally rare MHC alleles (not necessarily immigrants) were associated with heavier infections. Our results illustrate the complex relationship between MHC IIβ allelic variation and spatially varying multispecies parasite communities: different hypotheses may be concurrently true for different allele-parasite combinations. © 2017 John Wiley & Sons Ltd.

  1. Leukocyte Ig-Like Receptors – a model for MHC class I disease associations

    Directory of Open Access Journals (Sweden)

    Rachel Louise Allen

    2016-07-01

    Full Text Available MHC class I (MHC-I polymorphisms are associated with the outcome of some viral infections and autoimmune diseases. MHC-I proteins present antigenic peptides and are recognised by receptors on Natural Killer cells and Cytotoxic T lymphocytes, thus enabling the immune system to detect self-antigens and eliminate targets lacking self or expressing foreign antigens. Recognition of MHC-I, however, extends beyond receptors on cytotoxic leukocytes. Members of the Leukocyte Ig-like receptor (LILR family are expressed on monocytic cells and can recognise both classical and non-classical MHC-I alleles. Despite their relatively broad specificity when compared to the T Cell Receptor or Killer Ig-like Receptors, variations in the strength of LILR binding between different MHC-I alleles have recently been shown to correlate with control of HIV infection. We suggest that LILR recognition may mediate MHC-I disease association in a manner that does not depend on a binary discrimination of self/non-self by cytotoxic cells. Instead, the effects of LILR activity following engagement by MHC-I may represent a degrees of self model, whereby strength of binding to different alleles determines the degree of influence exerted by these receptors on immune cell functions. LILR are expressed by myelomonocytic cells and lymphocytes, extending their influence across antigen presenting cell subsets including dendritic cells, macrophages and B cells. They have been identified as important players in the response to infection, inflammatory diseases and cancer, with recent literature to indicate that MHC-I recognition by these receptors and consequent allelic effects could extend an influence beyond the immune system.

  2. Crystal structure of a TAPBPR–MHC I complex reveals the mechanism of peptide editing in antigen presentation

    Energy Technology Data Exchange (ETDEWEB)

    Jiang, Jiansheng; Natarajan, Kannan; Boyd, Lisa F.; Morozov, Giora I.; Mage, Michael G.; Margulies, David H. (NIH); (Hebrew)

    2017-10-12

    Central to CD8+ T cell–mediated immunity is the recognition of peptide–major histocompatibility complex class I (p–MHC I) proteins displayed by antigen-presenting cells. Chaperone-mediated loading of high-affinity peptides onto MHC I is a key step in the MHC I antigen presentation pathway. However, the structure of MHC I with a chaperone that facilitates peptide loading has not been determined. We report the crystal structure of MHC I in complex with the peptide editor TAPBPR (TAP-binding protein–related), a tapasin homolog. TAPBPR remodels the peptide-binding groove of MHC I, resulting in the release of low-affinity peptide. Changes include groove relaxation, modifications of key binding pockets, and domain adjustments. This structure captures a peptide-receptive state of MHC I and provides insights into the mechanism of peptide editing by TAPBPR and, by analogy, tapasin.

  3. Characterization of MHC-I in the blue tit (Cyanistes caeruleus) reveals low levels of genetic diversity and trans-population evolution across European populations

    NARCIS (Netherlands)

    Schut, Elske; Rivero-de Aguilar, Juan; Merino, Santiago; Magrath, Michael J. L.; Komdeur, Jan; Westerdahl, Helena

    The major histcompatibility complex (MHC) is a vital component of the adaptive immune system in all vertebrates. This study is the first to characterize MHC class I (MHC-I) in blue tits (Cyanistes caeruleus), and we use MHC-I exon 3 sequence data from individuals originating from three locations

  4. pH dependence of MHC class I-restricted peptide presentation

    DEFF Research Database (Denmark)

    Stryhn, A; Pedersen, L O; Romme, T

    1996-01-01

    The function of MHC class I molecules is to bind and present antigenic peptides to cytotoxic T cells. Here, we report that class I-restricted peptide presentation is strongly pH dependent. The presentation of some peptides was enhanced at acidic pH, whereas the presentation of others was inhibited....... Biochemical peptide-MHC class I binding assays demonstrated that peptide-MHC class I complexes are more stable at neutral pH than at acidic pH. We suggest that acid-dependent peptide dissociation can generate empty class I molecules and that the resulting binding potential can be exploited by a subset...

  5. Systematic Characterisation of Cellular Localisation and Expression Profiles of Proteins Containing MHC Ligands

    DEFF Research Database (Denmark)

    Juncker, Agnieszka; Larsen, Mette Voldby; Weinhold, Nils

    2009-01-01

    Background: Presentation of peptides on Major Histocompatibility Complex (MHC) molecules is the cornerstone in immune system activation and increased knowledge of the characteristics of MHC ligands and their source proteins is highly desirable. Methodology/Principal Finding: In the present large......-scale study, we used a large data set of proteins containing experimentally identified MHC class I or II ligands and examined the proteins according to their expression profiles at the mRNA level and their Gene Ontology (GO) classification within the cellular component ontology. Proteins encoded by highly...

  6. Improved prediction of MHC class I and class II epitopes using a novel Gibbs sampling approach

    DEFF Research Database (Denmark)

    Nielsen, Morten; Lundegaard, Claus; Worning, Peder

    2004-01-01

    Prediction of which peptides will bind a specific major histocompatibility complex (MHC) constitutes an important step in identifying potential T-cell epitopes suitable as vaccine candidates. MHC class II binding peptides have a broad length distribution complicating such predictions. Thus......, identifying the correct alignment is a crucial part of identifying the core of an MHC class II binding motif. In this context, we wish to describe a novel Gibbs motif sampler method ideally suited for recognizing such weak sequence motifs. The method is based on the Gibbs sampling method, and it incorporates...

  7. Low genetic variation in the MHC class II DRB gene and MHC-linked microsatellites in endangered island populations of the leopard cat (Prionailurus bengalensis) in Japan.

    Science.gov (United States)

    Saka, Toshinori; Nishita, Yoshinori; Masuda, Ryuichi

    2018-02-01

    Isolated populations of the leopard cat (Prionailurus bengalensis) on Tsushima and Iriomote islands in Japan are classified as subspecies P. b. euptilurus and P. b. iriomotensis, respectively. Because both populations have decreased to roughly 100, an understanding of their genetic diversity is essential for conservation. We genotyped MHC class II DRB exon 2 and MHC-linked microsatellite loci to evaluate the diversity of MHC genes in the Tsushima and Iriomote cat populations. We detected ten and four DRB alleles in these populations, respectively. A phylogenetic analysis showed DRB alleles from both populations to be closely related to those in other felid DRB lineages, indicating trans-species polymorphism. The MHC-linked microsatellites were more polymorphic in the Tsushima than in the Iriomote population. The MHC diversity of both leopard cat populations is much lower than in the domestic cat populations on these islands, probably due to inbreeding associated with founder effects, geographical isolation, or genetic drift. Our results predict low resistance of the two endangered populations to new pathogens introduced to the islands.

  8. Heavy baryons

    International Nuclear Information System (INIS)

    Koerner, J.G.

    1994-06-01

    We review the experimental and theoretical status of baryons containing one heavy quark. The charm and bottom baryon states are classified and their mass spectra are listed. The appropriate theoretical framework for the description of heavy baryons is the Heavy Quark Effective Theory, whose general ideas and methods are introduced and illustrated in specific examples. We present simple covariant expressions for the spin wave functions of heavy baryons including p-wave baryons. The covariant spin wave functions are used to determine the Heavy Quark Symmetry structure of flavour-changing current-induced transitions between heavy baryons as well as one-pion and one-photon transitions between heavy baryons of the same flavour. We discuss 1/m Q corrections to the current-induced transitions as well as the structure of heavy to light baryon transitions. Whenever possible we attempt to present numbers to compare with experiment by making use of further model-dependent assumptions as e.g. the constituent picture for light quarks. We highlight recent advances in the theoretical understanding of the inclusive decays of hadrons containing one heavy quark including polarization. For exclusive semileptonic decays we discuss rates, angular decay distributions and polarization effects. We provide an update of the experimental and theoretical status of lifetimes of heavy baryons and of exclusive nonleptonic two body decays of charm baryons. (orig.)

  9. High yield production of human invariant chain CD74 constructs fused to solubility-enhancing peptides and characterization of their MIF-binding capacities

    NARCIS (Netherlands)

    Kok, Tjie; Wasiel, Anna A; Dekker, Frank J; Poelarends, Gerrit J; Cool, Robbert H

    2018-01-01

    The HLA class II histocompatibility antigen gamma chain, also known as HLA-DR antigen-associated invariant chain or CD74, has been shown to be involved in many biological processes amongst which antigen loading and transport of MHC class II molecules from the endoplasmic reticulum to the Golgi

  10. Falling chains

    OpenAIRE

    Wong, Chun Wa; Yasui, Kosuke

    2005-01-01

    The one-dimensional fall of a folded chain with one end suspended from a rigid support and a chain falling from a resting heap on a table is studied. Because their Lagrangians contain no explicit time dependence, the falling chains are conservative systems. Their equations of motion are shown to contain a term that enforces energy conservation when masses are transferred between subchains. We show that Cayley's 1857 energy nonconserving solution for a chain falling from a resting heap is inco...

  11. Heavy flavors

    International Nuclear Information System (INIS)

    Cox, B.; Gilman, F.J.; Gottschalk, T.D.

    1986-11-01

    A range of issues pertaining to heavy flavors at the SSC is examined including heavy flavor production by gluon-gluon fusion and by shower evolution of gluon jets, flavor tagging, reconstruction of Higgs and W bosons, and the study of rare decays and CP violation in the B meson system. A specific detector for doing heavy flavor physics and tuned to this latter study at the SSC, the TASTER, is described. 36 refs., 10 figs

  12. Molecular Basis of Natural Killer Cell Tumor Target Recognition: The NKr/MHC Class I Complex

    National Research Council Canada - National Science Library

    Hasemann, Charles

    1999-01-01

    .... We have pursued this via the heterologous expression of wild type and mutant NK receptors for the purpose of the determination of the atomic structure of an NK receptor/ class I MHC complex via X-ray crystallography...

  13. A Novel Therapeutic Vaccine for Metastatic Mammary Carcinoma: Focusing MHC/Peptide Complexes to Lipid Rafts

    National Research Council Canada - National Science Library

    Dolan, Brian

    2004-01-01

    Genetic engineering of tumor cells to express MHC class and subsequent use of said cells for treatment of established and metastatic tumors has yielded promising results in animal models for treatment of breast cancer...

  14. ZAP-70 and p72syk are signaling response elements through MHC class II molecules

    DEFF Research Database (Denmark)

    Kanner, S B; Grosmaire, L S; Blake, J

    1995-01-01

    Ligation of major histocompatibility complex (MHC) class II antigens expressed on antigen-activated human CD4+ T-lymphocytes induces early signal transduction events including the activation of tyrosine kinases, the tyrosine phosphorylation of phospholipase-C gamma 1 and the mobilization...... of intracellular calcium. Similar responses have been observed in B-cells following stimulation of MHC class II molecules, including the increased production of intracellular cAMP. In this report, we demonstrate that the ZAP-70 tyrosine kinase is a responsive signaling element following cross-linking of HLA...... by herbimycin A. MHC class II ligation on B-lymphocytes resulted in cell death, which was both qualitatively distinct from Fas-induced apoptosis and partially protected by herbimycin A pretreatment. Thus, ligation of MHC class II molecules expressed on human lymphocytes stimulates the ZAP-70/p72syk family...

  15. Barrett associated MHC and FOXF1 variants also increase esophageal carcinoma risk

    NARCIS (Netherlands)

    Dura, P.; Veen, E.M. van; Salomon, J.; Morsche, R.H.M. te; Roelofs, H.M.J.; Kristinsson, J.O.; Wobbes, T.; Witteman, B.J.; Tan, A.C.; Drenth, J.P.H.; Peters, W.H.M.

    2013-01-01

    Barrett's esophagus, with gastroesophageal reflux disease and obesity as risk factors, predisposes to esophageal adenocarcinoma (EAC). Recently a British genome wide association study identified two Barrett's esophagus susceptibility loci mapping within the major histocompatibility complex (MHC;

  16. Forming a complex with MHC class I molecules interferes with mouse CD1d functional expression.

    Directory of Open Access Journals (Sweden)

    Renukaradhya J Gourapura

    Full Text Available CD1d molecules are structurally similar to MHC class I, but present lipid antigens as opposed to peptides. Here, we show that MHC class I molecules physically associate with (and regulate the functional expression of mouse CD1d on the surface of cells. Low pH (3.0 acid stripping of MHC class I molecules resulted in increased surface expression of murine CD1d on antigen presenting cells as well as augmented CD1d-mediated antigen presentation to NKT cells. Consistent with the above results, TAP1-/- mice were found to have a higher percentage of type I NKT cells as compared to wild type mice. Moreover, bone marrow-derived dendritic cells from TAP1-/- mice showed increased antigen presentation by CD1d compared to wild type mice. Together, these results suggest that MHC class I molecules can regulate NKT cell function, in part, by masking CD1d.

  17. MHC class I is functionally associated with antigen receptors in human T and B lymphomas

    DEFF Research Database (Denmark)

    Pedersen, Anders Elm; Jacoby, B F; Skov, S

    1996-01-01

    lines the increase in [Ca2+]i after MHC-I cross-linking caused upregulation of CD69, an early marker of activation. When studying the effect of MHC-I cross-linking on the TCR- and B cell antigen receptor (BCR)- mediated increase in [Ca2+]i, respectively, we observed that MHC-I had a costimulatory effect...... on the TCR-mediated increase in [Ca2+]i in Jurkat cells but not on the anti-IgM-mediated activity of Solubo cells. Studies of subpopulations of Jurkat and Solubo cells expressing different levels of MHC-I on their cell surfaces revealed that the TCR- and BCR-mediated increases in [Ca2+]i, respectively, were...

  18. Semi-empirical quantum evaluation of peptide - MHC class II binding

    Science.gov (United States)

    González, Ronald; Suárez, Carlos F.; Bohórquez, Hugo J.; Patarroyo, Manuel A.; Patarroyo, Manuel E.

    2017-01-01

    Peptide presentation by the major histocompatibility complex (MHC) is a key process for triggering a specific immune response. Studying peptide-MHC (pMHC) binding from a structural-based approach has potential for reducing the costs of investigation into vaccine development. This study involved using two semi-empirical quantum chemistry methods (PM7 and FMO-DFTB) for computing the binding energies of peptides bonded to HLA-DR1 and HLA-DR2. We found that key stabilising water molecules involved in the peptide binding mechanism were required for finding high correlation with IC50 experimental values. Our proposal is computationally non-intensive, and is a reliable alternative for studying pMHC binding interactions.

  19. Structural requirements for the interaction between class II MHC molecules and peptide antigens

    DEFF Research Database (Denmark)

    Sette, A; Buus, S; Appella, E

    1990-01-01

    of binding, it is possible to define certain structural features of peptides that are associated with the capacity to bind to a particular MHC specificity (IA(d) or IE(d)); 3) IA(d) and IE(d) molecules recognize different and independent structures on the antigen molecule; 4) only about 10% of the single...... IA(d) and IE(d) molecules and their peptide ligands, we found that some structural characteristics apply to both antigen-MHC interactions. In particular, we found: 1) each MHC molecule is capable of binding many unrelated peptides through the same peptide-binding site; 2) despite this permissiveness...... amino acid substitutions tested on two IA(d)- and IE(d)-binding peptides had significant effect on their MHC-binding capacities, while over 80% of these substitutions significantly impaired T cell recognition of the Ia-peptide complex; 5) based on the segregation between residues that are crucial for T...

  20. Diagnostic value of MHC class I staining in idiopathic inflammatory myopathies.

    NARCIS (Netherlands)

    Pas, J. van der; Hengstman, G.J.D.; Laak, H.J. ter; Borm, G.F.; Engelen, B.G.M. van

    2004-01-01

    BACKGROUND: Identification of mononuclear cellular infiltrates in skeletal muscle tissue is the histological cornerstone of the diagnosis of idiopathic inflammatory myopathy (IIM). However, these infiltrates are not always present. OBJECTIVE: To determine whether MHC class I antigen expression on

  1. IRF-4-mediated CIITA transcription is blocked by KSHV encoded LANA to inhibit MHC II presentation.

    Directory of Open Access Journals (Sweden)

    Qiliang Cai

    2013-10-01

    Full Text Available Peptides presentation to T cells by MHC class II molecules is of importance in initiation of immune response to a pathogen. The level of MHC II expression directly influences T lymphocyte activation and is often targeted by various viruses. Kaposi's sarcoma-associated herpesvirus (KSHV encoded LANA is known to evade MHC class I peptide processing, however, the effect of LANA on MHC class II remains unclear. Here, we report that LANA down-regulates MHC II expression and presentation by inhibiting the transcription of MHC II transactivator (CIITA promoter pIII and pIV in a dose-dependent manner. Strikingly, although LANA knockdown efficiently disrupts the inhibition of CIITA transcripts from its pIII and pIV promoter region, the expression of HLA-DQβ but no other MHC II molecules was significantly restored. Moreover, we revealed that the presentation of HLA-DQβ enhanced by LANA knockdown did not help LANA-specific CD4+ T cell recognition of PEL cells, and the inhibition of CIITA by LANA is independent of IL-4 or IFN-γ signaling but dependent on the direct interaction of LANA with IRF-4 (an activator of both the pIII and pIV CIITA promoters. This interaction dramatically blocked the DNA-binding ability of IRF-4 on both pIII and pIV promoters. Thus, our data implies that LANA can evade MHC II presentation and suppress CIITA transcription to provide a unique strategy of KSHV escape from immune surveillance by cytotoxic T cells.

  2. Identification of the cognate peptide-MHC target of T cell receptors using molecular modeling and force field scoring

    DEFF Research Database (Denmark)

    Lanzarotti, Esteban; Marcatili, Paolo; Nielsen, Morten

    2018-01-01

    Interactions of T cell receptors (TCR) to peptides in complex with MHC (p:MHC) are key features that mediate cellular immune responses. While MHC binding is required for a peptide to be presented to T cells, not all MHC binders are immunogenic. The interaction of a TCR to the p:MHC complex holds...... terms. Building a benchmark of TCR:p:MHC complexes where epitopes and non-epitopes are modelled using state-of-the-art molecular modelling tools, scoring p:MHC to a given TCR using force-fields, optimized in a cross-validation setup to evaluate TCR inter atomic interactions involved with each p:MHC, we...... and model the TCR:p:MHC complex structure. In summary, we conclude that it is possible to identify the TCR cognate target among different candidate peptides by using a force-field based model, and believe this works could lay the foundation for future work within prediction of TCR:p:MHC interactions....

  3. MHC and non-MHC genes regulate elimination of lymphocytic choriomeningitis virus and antiviral cytotoxic T lymphocyte and delayed-type hypersensitivity mediating T lymphocyte activity in parallel

    DEFF Research Database (Denmark)

    Thomsen, Allan Randrup; Marker, O

    1989-01-01

    with regard to all three parameters was recessive, indicating that natural tolerance is not the mechanism explaining non-MHC dependent low responsiveness in this system. The implications of these findings are discussed with specific reference to the role of MHC genes in controlling resistance to infectious......, indicating that both H-2 and non-H-2 genes may influence the elimination of this virus. Differences in virus spread prior to appearance of the immune response could not explain the observed differences in clearance rate. On the other hand, inefficient clearance always correlated with low T cell...

  4. Characterization of MHC class I in a long distance migratory wader, the Icelandic black-tailed godwit.

    Science.gov (United States)

    Pardal, Sara; Drews, Anna; Alves, José A; Ramos, Jaime A; Westerdahl, Helena

    2017-07-01

    The major histocompatibility complex (MHC) encodes proteins that are central for antigen presentation and pathogen elimination. MHC class I (MHC-I) genes have attracted a great deal of interest among researchers in ecology and evolution and have been partly characterized in a wide range of bird species. So far, the main focus has been on species within the bird orders Galliformes and Passeriformes, while Charadriiformes remain vastly underrepresented with only two species studied to date. These two Charadriiformes species exhibit striking differences in MHC-I characteristics and MHC-I diversity. We therefore set out to study a third species within Charadriiformes, the Icelandic subspecies of black-tailed godwits (Limosa limosa islandica). This subspecies is normally confined to parasite-poor environments, and we hence expected low MHC diversity. MHC-I was partially characterized first using Sanger sequencing and then using high-throughput sequencing (MiSeq) in 84 individuals. We verified 47 nucleotide alleles in open reading frame with classical MHC-I characteristics, and each individual godwit had two to seven putatively classical MHC alleles. However, in contrast to previous MHC-I data within Charadriiformes, we did not find any evidence of alleles with low sequence diversity, believed to represent non-classical MHC genes. The diversity and divergence of the godwits MHC-I genes to a large extent fell between the previous estimates within Charadriiformes. However, the MHC genes of the migratory godwits had few sites subject to positive selection, and one possible explanation could be a low exposure to pathogens.

  5. Characterization of MHC class I and II genes in a subantarctic seabird, the blue petrel, Halobaena caerulea (Procellariiformes).

    Science.gov (United States)

    Strandh, Maria; Lannefors, Mimi; Bonadonna, Francesco; Westerdahl, Helena

    2011-10-01

    The great polymorphism observed in the major histocompatibility complex (MHC) genes is thought to be maintained by pathogen-mediated selection possibly combined with MHC-disassortative mating, guided by MHC-determined olfactory cues. Here, we partly characterize the MHC class I and II B of the blue petrel, Halobaena caerulea (Procellariiformes), a bird with significant olfactory abilities that lives under presumably low pathogen burdens in Subantarctica. Blue petrels are long-lived, monogamous birds which suggest the necessity of an accurate mate choice process. The species is ancestral to songbirds (Passeriformes; many MHC loci), although not to gamefowls (Galliformes; few MHC loci). Considering the phylogenetic relationships and the low subantarctic pathogen burden, we expected few rather than many MHC loci in the blue petrel. However, when we analysed partial MHC class I and class II B cDNA and gDNA sequences we found evidence for as many as at least eight MHC class I loci and at least two class II B loci. These class I and II B sequences showed classical MHC characteristics, e.g. high nucleotide diversity, especially in putative peptide-binding regions where signatures of positive selection was detected. Trans-species polymorphism was found between MHC class II B sequences of the blue petrel and those of thin-billed prion, Pachyptila belcheri, two species that diverged ∼25 MYA. The observed MHC allele richness in the blue petrel may well serve as a basis for mate choice, especially since olfactory discrimination of MHC types may be possible in this species.

  6. Variation in MHC genotypes in two populations of house sparrow (Passer domesticus) with different population histories.

    Science.gov (United States)

    Borg, Asa Alexandra; Pedersen, Sindre Andre; Jensen, Henrik; Westerdahl, Helena

    2011-10-01

    Small populations are likely to have a low genetic ability for disease resistance due to loss of genetic variation through inbreeding and genetic drift. In vertebrates, the highest genetic diversity of the immune system is located at genes within the major histocompatibility complex (MHC). Interestingly, parasite-mediated selection is thought to potentially maintain variation at MHC loci even in populations that are monomorphic at other loci. Therefore, general loss of genetic variation in the genome may not necessarily be associated with low variation at MHC loci. We evaluated inter- and intrapopulation variation in MHC genotypes between an inbred (Aldra) and a relatively outbred population (Hestmannøy) of house sparrows (Passer domesticus) in a metapopulation at Helgeland, Norway. Genomic (gDNA) and transcribed (cDNA) alleles of functional MHC class I and IIB loci, along with neutral noncoding microsatellite markers, were analyzed to obtain relevant estimates of genetic variation. We found lower allelic richness in microsatellites in the inbred population, but high genetic variation in MHC class I and IIB loci in both populations. This suggests that also the inbred population could be under balancing selection to maintain genetic variation for pathogen resistance.

  7. An MHC class I immune evasion gene of Marek׳s disease virus.

    Science.gov (United States)

    Hearn, Cari; Preeyanon, Likit; Hunt, Henry D; York, Ian A

    2015-01-15

    Marek׳s disease virus (MDV) is a widespread α-herpesvirus of chickens that causes T cell tumors. Acute, but not latent, MDV infection has previously been shown to lead to downregulation of cell-surface MHC class I (Virology 282:198-205 (2001)), but the gene(s) involved have not been identified. Here we demonstrate that an MDV gene, MDV012, is capable of reducing surface expression of MHC class I on chicken cells. Co-expression of an MHC class I-binding peptide targeted to the endoplasmic reticulum (bypassing the requirement for the TAP peptide transporter) partially rescued MHC class I expression in the presence of MDV012, suggesting that MDV012 is a TAP-blocking MHC class I immune evasion protein. This is the first unique non-mammalian MHC class I immune evasion gene identified, and suggests that α-herpesviruses have conserved this function for at least 100 million years. Copyright © 2014 Elsevier Inc. All rights reserved.

  8. No evidence for the effect of MHC on male mating success in the brown bear.

    Science.gov (United States)

    Kuduk, Katarzyna; Babik, Wieslaw; Bellemain, Eva; Valentini, Alice; Zedrosser, Andreas; Taberlet, Pierre; Kindberg, Jonas; Swenson, Jon E; Radwan, Jacek

    2014-01-01

    Mate choice is thought to contribute to the maintenance of the spectacularly high polymorphism of the Major Histocompatibility Complex (MHC) genes, along with balancing selection from parasites, but the relative contribution of the former mechanism is debated. Here, we investigated the association between male MHC genotype and mating success in the brown bear. We analysed fragments of sequences coding for the peptide-binding region of the highly polymorphic MHC class I and class II DRB genes, while controlling for genome-wide effects using a panel of 18 microsatellite markers. Male mating success did not depend on the number of alleles shared with the female or amino-acid distance between potential mates at either locus. Furthermore, we found no indication of female mating preferences for MHC similarity being contingent on the number of alleles the females carried. Finally, we found no significant association between the number of MHC alleles a male carried and his mating success. Thus, our results provided no support for the role of mate choice in shaping MHC polymorphism in the brown bear.

  9. Preferrential rearrangement in normal rabbits of the 3' VHa allotype gene that is deleted in Alicia mutants; somatic hypermutation/conversion may play a major role in generating the heterogeneity of rabbit heavy chain variable region sequences.

    Science.gov (United States)

    Allegrucci, M; Young-Cooper, G O; Alexander, C B; Newman, B A; Mage, R G

    1991-02-01

    The rabbit is unique in having well-defined allotypes in the variable region of the heavy chain. Products of the VHa locus, (with alleles a1, a2, and a3), account for the majority of the serum immunoglobulins. A small percentage of the serum immunoglobulins are a-negative. In 1986, Kelus and Weiss described a mutation that depressed the expression of the Ig VH a2 genes in an a1/a2 rabbit. From this animal the Alicia rabbit strain was developed and the mutation was termed ali. We previously showed, using Southern analysis and the transverse alternating field electrophoresis technique, that the difference between the ali rabbit and normal is a relatively small deletion including some of the most 3' VH genes. The most JH proximal 3' VH1 genes in DNA from normal rabbits of a1, a2 and a3 haplotypes encode a1, a2 and a3 molecules respectively, and it has been suggested that these genes are responsible for allelic inheritance of VHa allotypes. The present study suggests that the 3' end of the VH locus probably plays a key role in regulation of VH gene expression in rabbits because VH gene(s) in this region are the target(s) of preferential VDJ rearrangements. This raises the possibility that mechanisms such as somatic gene conversion and hypermutation are at work to generate the antibody repertoire in this species. Our data support the view that the 3' VH1 gene may be the preferred target for rearrangement in normal rabbits, and for the normal chromosome in heterozygous ali animals. However, homozygous ali rabbits with a deletion that removed the a2-encoding VH1 on both chromosomes do survive, rearrange other VH genes and produce normal levels of immunoglobulins as well as a significant percentage of B cells which bear the a2 allotype. This challenges the view that one VH gene, VH1, is solely responsible for the inheritance pattern of VHa allotypes.

  10. MHC class II expression through a hitherto unknown pathway supports T helper cell-dependent immune responses: implications for MHC class II deficiency

    NARCIS (Netherlands)

    Buch, Thorsten; Polic, Bojan; Clausen, Björn E.; Weiss, Susanne; Akilli-Ozturk, Ozlem; Chang, Cheong-Hee; Flavell, Richard; Schulz, Ansgar; Jonjic, Stipan; Waisman, Ari; Förster, Irmgard

    2006-01-01

    MHC class II (MHCII) deficiency or bare lymphocyte syndrome (BLS) is a severe immunodeficiency characterized by deficient T helper (Th)-cell-dependent immunity. The disease is caused by defects of the MHCII promoter complex resulting in low or absent MHCII expression. We demonstrate in a murine

  11. Comparative genomic analysis of the MHC: the evolution of class I duplication blocks, diversity and complexity from shark to man.

    Science.gov (United States)

    Kulski, Jerzy K; Shiina, Takashi; Anzai, Tatsuya; Kohara, Sakae; Inoko, Hidetoshi

    2002-12-01

    The major histocompatibility complex (MHC) genomic region is composed of a group of linked genes involved functionally with the adaptive and innate immune systems. The class I and class II genes are intrinsic features of the MHC and have been found in all the jawed vertebrates studied so far. The MHC genomic regions of the human and the chicken (B locus) have been fully sequenced and mapped, and the mouse MHC sequence is almost finished. Information on the MHC genomic structures (size, complexity, genic and intergenic composition and organization, gene order and number) of other vertebrates is largely limited or nonexistent. Therefore, we are mapping, sequencing and analyzing the MHC genomic regions of different human haplotypes and at least eight nonhuman species. Here, we review our progress with these sequences and compare the human MHC structure with that of the nonhuman primates (chimpanzee and rhesus macaque), other mammals (pigs, mice and rats) and nonmammalian vertebrates such as birds (chicken and quail), bony fish (medaka, pufferfish and zebrafish) and cartilaginous fish (nurse shark). This comparison reveals a complex MHC structure for mammals and a relatively simpler design for nonmammalian animals with a hypothetical prototypic structure for the shark. In the mammalian MHC, there are two to five different class I duplication blocks embedded within a framework of conserved nonclass I and/or nonclass II genes. With a few exceptions, the class I framework genes are absent from the MHC of birds, bony fish and sharks. Comparative genomics of the MHC reveal a highly plastic region with major structural differences between the mammalian and nonmammalian vertebrates. Additional genomic data are needed on animals of the reptilia, crocodilia and marsupial classes to find the origins of the class I framework genes and examples of structures that may be intermediate between the simple and complex MHC organizations of birds and mammals, respectively.

  12. Peripheral nerve injury causes transient expression of MHC class I antigens in rat motor neurons and skeletal muscles

    DEFF Research Database (Denmark)

    Maehlen, J; Nennesmo, I; Olsson, A B

    1989-01-01

    After a peripheral nerve lesion (rat facial and sciatic) an induction of major histocompatibility complex (MHC) antigens class I was detected immunohistochemically in skeletal muscle fibers and motor neurons. This MHC expression was transient after a nerve crush, when regeneration occurred......, but persisted after a nerve cut, when regeneration was prevented. Since the time course of MHC class I expression correlates to that of regeneration a role for this cell surface molecule in regeneration may be considered....

  13. Prediction of the binding affinities of peptides to class II MHC using a regularized thermodynamic model

    Directory of Open Access Journals (Sweden)

    Mittelmann Hans D

    2010-01-01

    Full Text Available Abstract Background The binding of peptide fragments of extracellular peptides to class II MHC is a crucial event in the adaptive immune response. Each MHC allotype generally binds a distinct subset of peptides and the enormous number of possible peptide epitopes prevents their complete experimental characterization. Computational methods can utilize the limited experimental data to predict the binding affinities of peptides to class II MHC. Results We have developed the Regularized Thermodynamic Average, or RTA, method for predicting the affinities of peptides binding to class II MHC. RTA accounts for all possible peptide binding conformations using a thermodynamic average and includes a parameter constraint for regularization to improve accuracy on novel data. RTA was shown to achieve higher accuracy, as measured by AUC, than SMM-align on the same data for all 17 MHC allotypes examined. RTA also gave the highest accuracy on all but three allotypes when compared with results from 9 different prediction methods applied to the same data. In addition, the method correctly predicted the peptide binding register of 17 out of 18 peptide-MHC complexes. Finally, we found that suboptimal peptide binding registers, which are often ignored in other prediction methods, made significant contributions of at least 50% of the total binding energy for approximately 20% of the peptides. Conclusions The RTA method accurately predicts peptide binding affinities to class II MHC and accounts for multiple peptide binding registers while reducing overfitting through regularization. The method has potential applications in vaccine design and in understanding autoimmune disorders. A web server implementing the RTA prediction method is available at http://bordnerlab.org/RTA/.

  14. Low MHC variation in the endangered Galápagos penguin (Spheniscus mendiculus).

    Science.gov (United States)

    Bollmer, Jennifer L; Vargas, F Hernán; Parker, Patricia G

    2007-07-01

    The major histocompatibility complex (MHC) is one of the most polymorphic regions of the genome, likely due to balancing selection acting to maintain alleles over time. Lack of MHC variability has been attributed to factors such as genetic drift in small populations and relaxed selection pressure. The Galápagos penguin (Spheniscus mendiculus), endemic to the Galápagos Islands, is the only penguin that occurs on the equator. It relies upon cold, nutrient-rich upwellings and experiences severe population declines when ocean temperatures rise during El Niño events. These bottlenecks, occurring in an already small population, have likely resulted in reduced genetic diversity in this species. In this study, we used MHC class II exon 2 sequence data from a DRB1-like gene to characterize the amount of genetic variation at the MHC in 30 Galápagos penguins, as well as one Magellanic penguin (S. magellanicus) and two king penguins (Aptenodytes patagonicus), and compared it to that in five other penguin species for which published data exist. We found that the Galápagos penguin had the lowest MHC diversity (as measured by number of polymorphic sites and average divergence among alleles) of the eight penguin species studied. A phylogenetic analysis showed that Galápagos penguin MHC sequences are most closely related to Humboldt penguin (Spheniscus humboldti) sequences, its putative sister species based on other loci. An excess of non-synonymous mutations and a pattern of trans-specific evolution in the neighbor-joining tree suggest that selection is acting on the penguin MHC.

  15. Stepwise threshold clustering: a new method for genotyping MHC loci using next-generation sequencing technology.

    Directory of Open Access Journals (Sweden)

    William E Stutz

    Full Text Available Genes of the vertebrate major histocompatibility complex (MHC are of great interest to biologists because of their important role in immunity and disease, and their extremely high levels of genetic diversity. Next generation sequencing (NGS technologies are quickly becoming the method of choice for high-throughput genotyping of multi-locus templates like MHC in non-model organisms. Previous approaches to genotyping MHC genes using NGS technologies suffer from two problems:1 a "gray zone" where low frequency alleles and high frequency artifacts can be difficult to disentangle and 2 a similar sequence problem, where very similar alleles can be difficult to distinguish as two distinct alleles. Here were present a new method for genotyping MHC loci--Stepwise Threshold Clustering (STC--that addresses these problems by taking full advantage of the increase in sequence data provided by NGS technologies. Unlike previous approaches for genotyping MHC with NGS data that attempt to classify individual sequences as alleles or artifacts, STC uses a quasi-Dirichlet clustering algorithm to cluster similar sequences at increasing levels of sequence similarity. By applying frequency and similarity based criteria to clusters rather than individual sequences, STC is able to successfully identify clusters of sequences that correspond to individual or similar alleles present in the genomes of individual samples. Furthermore, STC does not require duplicate runs of all samples, increasing the number of samples that can be genotyped in a given project. We show how the STC method works using a single sample library. We then apply STC to 295 threespine stickleback (Gasterosteus aculeatus samples from four populations and show that neighboring populations differ significantly in MHC allele pools. We show that STC is a reliable, accurate, efficient, and flexible method for genotyping MHC that will be of use to biologists interested in a variety of downstream applications.

  16. New design of MHC class II tetramers to accommodate fundamental principles of antigen presentation.

    Science.gov (United States)

    Landais, Elise; Romagnoli, Pablo A; Corper, Adam L; Shires, John; Altman, John D; Wilson, Ian A; Garcia, K Christopher; Teyton, Luc

    2009-12-15

    Direct identification and isolation of Ag-specific T cells became possible with the development of MHC tetramers, based on fluorescent avidins displaying biotinylated peptide-MHC complexes. This approach, extensively used for MHC class I-restricted T cells, has met very limited success with class II peptide-MHC complex tetramers (pMHCT-2) for the detection of CD4(+)-specific T cells. In addition, a very large number of these reagents, although capable of specifically activating T cells after being coated on solid support, is still unable to stain. To try to understand this puzzle and design usable tetramers, we examined each parameter critical for the production of pMHCT-2 using the I-A(d)-OVA system as a model. Through this process, the geometry of peptide-MHC display by avidin tetramers was examined, as well as the stability of rMHC molecules. However, we discovered that the most important factor limiting the reactivity of pMHCT-2 was the display of peptides. Indeed, long peptides, as presented by MHC class II molecules, can be bound to I-A/HLA-DQ molecules in more than one register, as suggested by structural studies. This mode of anchorless peptide binding allows the selection of a broader repertoire on single peptides and should favor anti-infectious immune responses. Thus, beyond the technical improvements that we propose, the redesign of pMHCT-2 will give us the tools to evaluate the real size of the CD4 T cell repertoire and help us in the production and testing of new vaccines.

  17. Extensive shared polymorphism at non-MHC immune genes in recently diverged North American prairie grouse

    Science.gov (United States)

    Minias, Piotr; Bateson, Zachary W.; Whittingham, Linda A.; Johnson, Jeff A.; Oyler-McCance, Sara J.; Dunn, Peter O.

    2018-01-01

    Gene polymorphisms shared between recently diverged species are thought to be widespread and most commonly reflect introgression from hybridization or retention of ancestral polymorphism through incomplete lineage sorting. Shared genetic diversity resulting from incomplete lineage sorting is usually maintained for a relatively short period of time, but under strong balancing selection it may persist for millions of years beyond species divergence (balanced trans-species polymorphism), as in the case of the major histocompatibility complex (MHC) genes. However, balancing selection is much less likely to act on non-MHC immune genes. The aim of this study was to investigate the patterns of shared polymorphism and selection at non-MHC immune genes in five grouse species from Centrocercus and Tympanuchus genera. For this purpose, we genotyped five non-MHC immune genes that do not interact directly with pathogens, but are involved in signaling and regulate immune cell growth. In contrast to previous studies with MHC, we found no evidence for balancing selection or balanced trans-species polymorphism among the non-MHC immune genes. No haplotypes were shared between genera and in most cases more similar allelic variants sorted by genus. Between species within genera, however, we found extensive shared polymorphism, which was most likely attributable to introgression or incomplete lineage sorting following recent divergence and large ancestral effective population size (i.e., weak genetic drift). Our study suggests that North American prairie grouse may have attained relatively low degree of reciprocal monophyly at nuclear loci and reinforces the rarity of balancing selection in non-MHC immune genes.

  18. A new polymorphic and multicopy MHC gene family related to nonmammalian class I

    Energy Technology Data Exchange (ETDEWEB)

    Leelayuwat, C.; Degli-Esposti, M.A.; Abraham, L.J. [Univ. of Western Australia, Perth (Australia); Townend, D.C. [Sir Charles Gairdner Hospital, Perth (Australia); Dawkins, R.L. [Royal Perth Hospital, Perth (Australia)]|[Univ. of Western Australia, Perth (Australia)]|[Sir Charles Gairdner Hospital, Perth (Australia)

    1994-12-31

    The authors have used genomic analysis to characterize a region of the central major histocompatibility complex (MHC) spanning {approximately} 300 kilobases (kb) between TNF and HLA-B. This region has been suggested to carry genetic factors relevant to the development of autoimmune diseases such as myasthenia gravis (MG) and insulin dependent diabetes mellitus (IDDM). Genomic sequence was analyzed for coding potential, using two neural network programs, GRAIL and GeneParser. A genomic probe, JAB, containing putative coding sequences (PERB11) located 60 kb centromeric of HLA-B, was used for northern analysis of human tissues. Multiple transcripts were detected. Southern analysis of genomic DNA and overlapping YAC clones, covering the region from BAT1 to HLA-F, indicated that there are at least five copies of PERB11, four of which are located within this region of the MHC. The partial cDNA sequence of PERB11 was obtained from poly-A RNA derived from skeletal muscle. The putative amino acid sequence of PERB11 shares {approximately} 30% identity to MHC class I molecules from various species, including reptiles, chickens, and frogs, as well as to other MHC class I-like molecules, such as the IgG FcR of the mouse and rat and the human Zn-{alpha}2-glycoprotein. From direct comparison of amino acid sequences, it is concluded that PERB11 is a distinct molecule more closely related to nonmammalian than known mammalian MHC class I molecules. Genomic sequence analysis of PERB11 from five MHC ancestral haplotypes (AH) indicated that the gene is polymorphic at both DNA and protein level. The results suggest that the authors have identified a novel polymorphic gene family with multiple copies within the MHC. 48 refs., 10 figs., 2 tabs.

  19. The importance of immune gene variability (MHC in evolutionary ecology and conservation

    Directory of Open Access Journals (Sweden)

    Sommer Simone

    2005-10-01

    Full Text Available Abstract Genetic studies have typically inferred the effects of human impact by documenting patterns of genetic differentiation and levels of genetic diversity among potentially isolated populations using selective neutral markers such as mitochondrial control region sequences, microsatellites or single nucleotide polymorphism (SNPs. However, evolutionary relevant and adaptive processes within and between populations can only be reflected by coding genes. In vertebrates, growing evidence suggests that genetic diversity is particularly important at the level of the major histocompatibility complex (MHC. MHC variants influence many important biological traits, including immune recognition, susceptibility to infectious and autoimmune diseases, individual odours, mating preferences, kin recognition, cooperation and pregnancy outcome. These diverse functions and characteristics place genes of the MHC among the best candidates for studies of mechanisms and significance of molecular adaptation in vertebrates. MHC variability is believed to be maintained by pathogen-driven selection, mediated either through heterozygote advantage or frequency-dependent selection. Up to now, most of our knowledge has derived from studies in humans or from model organisms under experimental, laboratory conditions. Empirical support for selective mechanisms in free-ranging animal populations in their natural environment is rare. In this review, I first introduce general information about the structure and function of MHC genes, as well as current hypotheses and concepts concerning the role of selection in the maintenance of MHC polymorphism. The evolutionary forces acting on the genetic diversity in coding and non-coding markers are compared. Then, I summarise empirical support for the functional importance of MHC variability in parasite resistance with emphasis on the evidence derived from free-ranging animal populations investigated in their natural habitat. Finally, I

  20. Direct binding of autoimmune disease related T cell epitopes to purified Lewis rat MHC class II molecules

    DEFF Research Database (Denmark)

    Joosten, I; Wauben, M H; Holewijn, M C

    1994-01-01

    New strategies applied in the treatment of experimental autoimmune disease models involve blocking or modulation of MHC-peptide-TCR interactions either at the level of peptide-MHC interaction or, alternatively, at the level of T cell recognition. In order to identify useful competitor peptides one...... characteristics of the Lewis rat MHC class II RT1.B1 molecule. We have now developed a biochemical binding assay which enables competition studies in which the relative MHC binding affinity of a set of non-labelled peptides can be assessed while employing detection of biotinylated marker peptides...

  1. Evolutionary dynamics of an expressed MHC class IIβ locus in the Ranidae (Anura) uncovered by genome walking and high-throughput amplicon sequencing

    Science.gov (United States)

    Mulder, Kevin P.; Cortazar-Chinarro, Maria; Harris, D. James; Crottini, Angelica; Grant, Evan H. Campbell; Fleischer, Robert C.; Savage, Anna E.

    2017-01-01

    The Major Histocompatibility Complex (MHC) is a genomic region encoding immune loci that are important and frequently used markers in studies of adaptive genetic variation and disease resistance. Given the primary role of infectious diseases in contributing to global amphibian declines, we characterized the hypervariable exon 2 and flanking introns of the MHC Class IIβ chain for 17 species of frogs in the Ranidae, a speciose and cosmopolitan family facing widespread pathogen infections and declines. We find high levels of genetic variation concentrated in the Peptide Binding Region (PBR) of the exon. Ten codons are under positive selection, nine of which are located in the mammal-defined PBR. We hypothesize that the tenth codon (residue 21) is an amphibian-specific PBR site that may be important in disease resistance. Trans-species and trans-generic polymorphisms are evident from exon-based genealogies, and co-phylogenetic analyses between intron, exon and mitochondrial based reconstructions reveal incongruent topologies, likely due to different locus histories. We developed two sets of barcoded adapters that reliably amplify a single and likely functional locus in all screened species using both 454 and Illumina based sequencing methods. These primers provide a resource for multiplexing and directly sequencing hundreds of samples in a single sequencing run, avoiding the labour and chimeric sequences associated with cloning, and enabling MHC population genetic analyses. Although the primers are currently limited to the 17 species we tested, these sequences and protocols provide a useful genetic resource and can serve as a starting point for future disease, adaptation and conservation studies across a range of anuran taxa.

  2. Features of target cell lysis by class I and class II MHC restricted cytolytic T lymphocytes

    International Nuclear Information System (INIS)

    Maimone, M.M.; Morrison, L.A.; Braciale, V.L.; Braciale, T.J.

    1986-01-01

    The lytic activity of influenza virus-specific muvine cytolytic T lymphocyte (CTL) clones that are restricted by either H-2K/D (class I) or H-2I (class II) major histocompatibility (MHC) locus products was compared on an influenza virus-infected target cell expressing both K/D and I locus products. With the use of two in vitro measurements of cytotoxicity, conventional 51 Cr release, and detergent-releasable radiolabeled DNA (as a measure of nuclear disintegration in the early post-lethal hit period), the authors found no difference between class I and class II MHC-restricted CTL in the kinetics of target cell destruction. In addition, class II MHC-restricted antiviral CTL failed to show any lysis of radiolabeled bystander cells. Killing of labeled specific targets by these class II MHC-restricted CTL was also efficiently inhibited by unlabeled specific competitor cells in a cold target inhibition assay. In sum, these data suggest that class I and class II MHC-restricted CTL mediate target cell destruction by an essentially similar direct mechanism

  3. Identification, inheritance, and linkage of B-G-like and MHC class I genes in cranes.

    Science.gov (United States)

    Jarvi, S I; Goto, R M; Gee, G F; Briles, W E; Miller, M M

    1999-01-01

    We identified B-G-like genes in the whooping and Florida sandhill cranes and linked them to the major histocompatibility complex (MHC). We evaluated the inheritance of B-G-like genes in families of whooping and Florida sandhill cranes using restriction fragment patterns (RFPs). Two B-G-like genes, designated wcbg1 and wcbg2, were located within 8 kb of one another. The fully sequenced wcbg2 gene encodes a B-G IgV-like domain, an additional Ig-like domain, a transmembrane domain, and a single heptad domain typical of alpha-helical coiled coils. Patterns of restriction fragments in DNA from the whooping crane and from a number of other species indicate that the B-G-like gene families of cranes are large with diverse sequences. Segregation of RFPs in families of Florida sandhill cranes provide evidence for genetic polymorphism in the B-G-like genes. The restriction fragments generally segregated in concert with MHC haplotypes assigned by serological typing and by single stranded conformational polymorphism (SSCP) assays based in the second exon of the crane MHC class I genes. This study supports the concept of a long-term association of polymorphic B-G-like genes with the MHC. It also establishes SSCP as a means for evaluating MHC genetic variability in cranes.

  4. Identification, inheritance, and linkage of B-G-like and MHC class I genes in cranes

    Science.gov (United States)

    Jarvi, S.I.; Goto, R.M.; Gee, G.F.; Briles, W.E.; Miller, M.M.

    1999-01-01

    We identified B-G-like genes in the whooping and Florida sandhill cranes and linked them to the major histocompatibility complex (MHC). We evaluated the inheritance of B-G-like genes in families of whooping and Florida sandhill cranes using restriction fragment patterns (RFPs). Two B-G-like genes, designated wcbgl and wcbg2, were located within 8 kb of one another. The fully sequenced wcbg2 gene encodes a B-G IgV-like domain, an additional Ig-like domain, a transmembrane domain, and a single heptad domain typical of '-helical coiled coils. Patterns of restriction fragments in DNA from the whooping crane and from a number of other species indicate that the B-G-like gene families of cranes are large with diverse sequences. Segregation of RFPs in families of Florida sandhill cranes provide evidence for genetic polymorphism in the B-G-like genes. The restriction fragments generally segregated in concert with MHC haplotypes assigned by serological typing and by single stranded conformational polymorphism (SSCP) assays based in the second exon of the crane MHC class I genes. This study supports the concept of a long-term association of polymorphic B-G-like genes with the MHC. It also establishes SSCP as a means for evaluating MHC genetic variability in cranes.

  5. Molecular characterization of classical and nonclassical MHC class I genes from the golden pheasant (Chrysolophus pictus).

    Science.gov (United States)

    Zeng, Q-Q; Zhong, G-H; He, K; Sun, D-D; Wan, Q-H

    2016-02-01

    Classical major histocompatibility complex (MHC) class I allelic polymorphism is essential for competent antigen presentation. To improve the genotyping efforts in the golden pheasant, it is necessary to differentiate more accurately between classical and nonclassical class I molecules. In our study, all MHC class I genes were isolated from one golden pheasant based on two overlapping PCR amplifications. In total, six full-length class I nucleotide sequences (A-F) were identified, and four were novel. Two (A and C) belonged to the IA1 gene, two (B and D) were alleles derived from the IA2 gene through transgene amplification, and two (E and F) comprised a third novel locus, IA3 that was excluded from the core region of the golden pheasant MHC-B. IA1 and IA2 exhibited the broad expression profiles characteristic of classical loci, while IA3 showed no expression in multiple tissues and was therefore defined as a nonclassical gene. Phylogenetic analysis indicated that the three IA genes in the golden pheasant share a much closer evolutionary relationship than the corresponding sequences in other galliform species. This observation was consistent with high sequence similarity among them, which likely arises from the homogenizing effect of recombination. Our careful distinction between the classical and nonclassical MHC class I genes in the golden pheasant lays the foundation for developing locus-specific genotyping and establishing a good molecular marker system of classical MHC I loci. © 2015 John Wiley & Sons Ltd.

  6. Cell surface appearance of unexpected host MHC determinants on thymocytes from radiation bone marrow chimeras

    International Nuclear Information System (INIS)

    Sharrow, S.O.; Mathieson, B.J.; Singer, A.

    1981-01-01

    The phenotypic appearance of cell surface antigens on murine thymocytes from long-term radiation bone marrow chimeras was analyzed using indirect immunofluorescence and flow microfluorometry. Cells maturing in the thymi of these mice were typed for MHC (Kk, I-Ak, H-2b, Kb, and Ib) and non-MHC (Lty 1, Ly 9, and TL) determinants. All cells were of donor origin as determined by non-MHC (Ly) phenotype in P1 leads to P2, P1 x P2 leads to P1, and P1 leads to P2 radiation chimeras. In contrast, the MHC phenotypes of these thymocytes were markedly affected by the host environment. Specifically, H-2 and I-A determinants of both parental phenotypes were detected on thymocytes from P1 leads to P1 x P2 chimeras; I-A determinants of host phenotype were present, whereas I-A determinants of donor phenotype were reduced on thymocytes from P1 x P2 leads to P1 chimeras; and thymocytes from P1 leads to P2 chimeras possessed H-2 and I-A determinants of host phenotype but showed reduction of donor I-A phenotype determinants. The appearance of host cell surface H-2 and I-A determinants on thymocytes from chimeras closely parallels the functional recognition of MHC determinants by T cells from chimeric mice and thus may be significantly related to the development of the self-recognition repertoire by maturing T cells

  7. Characterization of 47 MHC class I sequences in Filipino cynomolgus macaques

    Science.gov (United States)

    Campbell, Kevin J.; Detmer, Ann M.; Karl, Julie A.; Wiseman, Roger W.; Blasky, Alex J.; Hughes, Austin L.; Bimber, Benjamin N.; O’Connor, Shelby L.; O’Connor, David H.

    2009-01-01

    Cynomolgus macaques (Macaca fascicularis) provide increasingly common models for infectious disease research. Several geographically distinct populations of these macaques from Southeast Asia and the Indian Ocean island of Mauritius are available for pathogenesis studies. Though host genetics may profoundly impact results of such studies, similarities and differences between populations are often overlooked. In this study we identified 47 full-length MHC class I nucleotide sequences in 16 cynomolgus macaques of Filipino origin. The majority of MHC class I sequences characterized (39 of 47) were unique to this regional population. However, we discovered eight sequences with perfect identity and six sequences with close similarity to previously defined MHC class I sequences from other macaque populations. We identified two ancestral MHC haplotypes that appear to be shared between Filipino and Mauritian cynomolgus macaques, notably a Mafa-B haplotype that has previously been shown to protect Mauritian cynomolgus macaques against challenge with a simian/human immunodeficiency virus, SHIV89.6P. We also identified a Filipino cynomolgus macaque MHC class I sequence for which the predicted protein sequence differs from Mamu-B*17 by a single amino acid. This is important because Mamu-B*17 is strongly associated with protection against simian immunodeficiency virus (SIV) challenge in Indian rhesus macaques. These findings have implications for the evolutionary history of Filipino cynomolgus macaques as well as for the use of this model in SIV/SHIV research protocols. PMID:19107381

  8. MHC-Dependent Mate Selection within 872 Spousal Pairs of European Ancestry from the Health and Retirement Study

    Directory of Open Access Journals (Sweden)

    Zhen Qiao

    2018-01-01

    Full Text Available Disassortative mating refers to the phenomenon in which individuals with dissimilar genotypes and/or phenotypes mate with one another more frequently than would be expected by chance. Although the existence of disassortative mating is well established in plant and animal species, the only documented example of negative assortment in humans involves dissimilarity at the major histocompatibility complex (MHC locus. Previous studies investigating mating patterns at the MHC have been hampered by limited sample size and contradictory findings. Inspired by the sparse and conflicting evidence, we investigated the role that the MHC region played in human mate selection using genome-wide association data from 872 European American spouses from the Health and Retirement Study (HRS. First, we treated the MHC region as a whole, and investigated genomic similarity between spouses using three levels of genomic variation: single-nucleotide polymorphisms (SNPs, classical human leukocyte antigen (HLA alleles (both four-digit and two-digit classifications, and amino acid polymorphisms. The extent of MHC dissimilarity between spouses was assessed using a permutation approach. Second, we investigated fine scale mating patterns by testing for deviations from random mating at individual SNPs, HLA genes, and amino acids in HLA molecules. Third, we assessed how extreme the spousal relatedness at the MHC region was compared to the rest of the genome, to distinguish the MHC-specific effects from genome-wide effects. We show that neither the MHC region, nor any single SNPs, classic HLA alleles, or amino acid polymorphisms within the MHC region, were significantly dissimilar between spouses relative to non-spouse pairs. However, dissimilarity in the MHC region was extreme relative to the rest of genome for both spousal and non-spouse pairs. Despite the long-standing controversy, our analyses did not support a significant role of MHC dissimilarity in human mate choice.

  9. Radioimmunoassay of myosin heavy beta chains in human serum for the evaluation of the size of myocardial infarction: correlation with myocardial Tl-201 SPECT and cardiac angioscintigraphy. Le dosage des chaines lourdes beta de la myosine serique dans l'approche de la taille de l'infarctus du myocarde: correlation avec la tomoscintigraphie myocardique au Tl-201 et l'angioscintigraphie cardiaque

    Energy Technology Data Exchange (ETDEWEB)

    Facello, A.; Gries, P.; Demangeat, C.; Brunot, B.; Roul, G.; Demangeat, J.L.; Moulichon, M.; Bareiss, P.; Sacrez, A.; Constantinesco, A. (Centre Hospitalier Universitaire Hautepierre, 67 - Strasbourg (FR))

    1990-01-01

    To determine the relationship between serum levels of myosin heavy beta chains assessed by an IRMA technique and other radionuclide and enzymatic parameters in the evaluation of the size of myocardial infarction, we studied 22 patients with acute myocardial infarction. Blood samples taken daily between 1st to 13th day of evolution allow the determination of peak and integral of myosine release that showed a good correlation (p<0.01) with myocardial underperfusion score in T1-201 SPECT, left ventricular ejection fractions at 1st day and at the pre-discharge study, just as CPK peak. This new assay is an interesting mean to evaluate the size of myocardial infarction.

  10. Inhibition of MHC class I is a virulence factor in herpes simplex virus infection of mice.

    Directory of Open Access Journals (Sweden)

    Mark T Orr

    2005-09-01

    Full Text Available Herpes simplex virus (HSV has a number of genes devoted to immune evasion. One such gene, ICP47, binds to the transporter associated with antigen presentation (TAP 1/2 thereby preventing transport of viral peptides into the endoplasmic reticulum, loading of peptides onto nascent major histocompatibility complex (MHC class I molecules, and presentation of peptides to CD8 T cells. However, ICP47 binds poorly to murine TAP1/2 and so inhibits antigen presentation by MHC class I in mice much less efficiently than in humans, limiting the utility of murine models to address the importance of MHC class I inhibition in HSV immunopathogenesis. To address this limitation, we generated recombinant HSVs that efficiently inhibit antigen presentation by murine MHC class I. These recombinant viruses prevented cytotoxic T lymphocyte killing of infected cells in vitro, replicated to higher titers in the central nervous system, and induced paralysis more frequently than control HSV. This increase in virulence was due to inhibition of antigen presentation to CD8 T cells, since these differences were not evident in MHC class I-deficient mice or in mice in which CD8 T cells were depleted. Inhibition of MHC class I by the recombinant viruses did not impair the induction of the HSV-specific CD8 T-cell response, indicating that cross-presentation is the principal mechanism by which HSV-specific CD8 T cells are induced. This inhibition in turn facilitates greater viral entry, replication, and/or survival in the central nervous system, leading to an increased incidence of paralysis.

  11. Genetic variation and selection of MHC class I loci differ in two congeneric frogs.

    Science.gov (United States)

    Kiemnec-Tyburczy, Karen M; Tracy, Karen E; Lips, Karen R; Zamudio, Kelly R

    2018-04-01

    Major histocompatibility complex (MHC) genes encode proteins in the acquired immune response pathway that often show distinctive selection-driven patterns in wild vertebrate populations. We examined genetic variation and signatures of selection in the MHC class I alpha 1 (A1)- and alpha 2 (A2)-domain encoding exons of two frog congeners [Agalychnis callidryas (n = 20) and A. lemur (n = 20)] from a single locality in Panama. We also investigated how historical demographic processes may have impacted MHC genetic diversity by analyzing a neutral mitochondrial marker. We found that both MHC domains were highly variable in both species, with both species likely expressing three loci. Our analyses revealed different signatures of selection between the two species, most notably that the A. callidryas A2 domain had experienced positive selection while the A2 domain of A. lemur had not. Diversifying selection acted on the same number of A1 and A2 allelic lineages, but on a higher percentage of A1 sites compared to A2 sites. Neutrality tests of mitochondrial haplotypes predominately indicated that the two species were at genetic equilibrium when the samples were collected. In addition, two historical tests of demography indicated both species have had relatively stable population sizes over the past 100,000 years; thus large population size changes are unlikely to have greatly influenced MHC diversity in either species during this time period. In conclusion, our results suggest that the impact of selection on MHC diversity varied between these two closely related species, likely due to a combination of distinct ecological conditions and past pathogenic pressures.

  12. Thermodynamics of T cell receptor – peptide/MHC interactions: progress and opportunities

    Science.gov (United States)

    Armstrong, Kathryn M.; Insaidoo, Francis K.; Baker, Brian M.

    2013-01-01

    αβ T cell receptors (TCR) recognize peptide antigens presented by class I or class II major histocompatibility complex molecules (pMHC). Here we review the use of thermodynamic measurements in the study of TCR-pMHC interactions, with attention to the diversity in binding thermodynamics and how this is related to the variation in TCR-pMHC interfaces. We show that there is no enthalpic or entropic signature for TCR binding; rather, enthalpy and entropy changes vary in a compensatory manner that reflects a narrow free energy window for the interactions that have been characterized. Binding enthalpy and entropy changes do not correlate with structural features such as buried surface area or the number of hydrogen bonds within TCR-pMHC interfaces, possibly reflecting the myriad of contributors to binding thermodynamics, but likely also reflecting a reliance on van’t Hoff over calorimetric measurements and the unaccounted influence of equilibria linked to binding. TCR-pMHC binding heat capacity changes likewise vary considerably. In some cases the heat capacity changes are consistent with conformational differences between bound and free receptors, but there is little data indicating these conformational differences represent the need to organize commonly disordered CDR loops. In this regard, we discuss how thermodynamics may provide additional insight into conformational changes occurring upon TCR binding. Finally, we highlight opportunities for the further use of thermodynamic measurements in the study of TCR-pMHC interactions, not only for understanding TCR binding in general, but for understanding specifics of individual interactions and the engineering of T cell receptors with desired molecular recognition properties. PMID:18496839

  13. MHC-I Ligand Discovery Using Targeted Database Searches of Mass Spectrometry Data: Implications for T-Cell Immunotherapies

    DEFF Research Database (Denmark)

    Murphy, J. Patrick; Konda, Prathyusha; Kowalewski, Daniel J.

    2017-01-01

    Class I major histocompatibility complex (MHC-I)-bound peptide ligands dictate the activation and specificity of CD8+ T cells and thus are important for devising T-cell immunotherapies. In recent times, advances in mass spectrometry (MS) have enabled the precise identification of these MHC-I pept...

  14. NN-align. An artificial neural network-based alignment algorithm for MHC class II peptide binding prediction

    Directory of Open Access Journals (Sweden)

    Lund Ole

    2009-09-01

    Full Text Available Abstract Background The major histocompatibility complex (MHC molecule plays a central role in controlling the adaptive immune response to infections. MHC class I molecules present peptides derived from intracellular proteins to cytotoxic T cells, whereas MHC class II molecules stimulate cellular and humoral immunity through presentation of extracellularly derived peptides to helper T cells. Identification of which peptides will bind a given MHC molecule is thus of great importance for the understanding of host-pathogen interactions, and large efforts have been placed in developing algorithms capable of predicting this binding event. Results Here, we present a novel artificial neural network-based method, NN-align that allows for simultaneous identification of the MHC class II binding core and binding affinity. NN-align is trained using a novel training algorithm that allows for correction of bias in the training data due to redundant binding core representation. Incorporation of information about the residues flanking the peptide-binding core is shown to significantly improve the prediction accuracy. The method is evaluated on a large-scale benchmark consisting of six independent data sets covering 14 human MHC class II alleles, and is demonstrated to outperform other state-of-the-art MHC class II prediction methods. Conclusion The NN-align method is competitive with the state-of-the-art MHC class II peptide binding prediction algorithms. The method is publicly available at http://www.cbs.dtu.dk/services/NetMHCII-2.0.

  15. Generation of a genomic tiling array of the human Major Histocompatibility Complex (MHC and its application for DNA methylation analysis

    Directory of Open Access Journals (Sweden)

    Ottaviani Diego

    2008-05-01

    Full Text Available Abstract Background The major histocompatibility complex (MHC is essential for human immunity and is highly associated with common diseases, including cancer. While the genetics of the MHC has been studied intensively for many decades, very little is known about the epigenetics of this most polymorphic and disease-associated region of the genome. Methods To facilitate comprehensive epigenetic analyses of this region, we have generated a genomic tiling array of 2 Kb resolution covering the entire 4 Mb MHC region. The array has been designed to be compatible with chromatin immunoprecipitation (ChIP, methylated DNA immunoprecipitation (MeDIP, array comparative genomic hybridization (aCGH and expression profiling, including of non-coding RNAs. The array comprises 7832 features, consisting of two replicates of both forward and reverse strands of MHC amplicons and appropriate controls. Results Using MeDIP, we demonstrate the application of the MHC array for DNA methylation profiling and the identification of tissue-specific differentially methylated regions (tDMRs. Based on the analysis of two tissues and two cell types, we identified 90 tDMRs within the MHC and describe their characterisation. Conclusion A tiling array covering the MHC region was developed and validated. Its successful application for DNA methylation profiling indicates that this array represents a useful tool for molecular analyses of the MHC in the context of medical genomics.

  16. High-throughput discovery of T cell epitopes in type 1 diabetes using DNA barcode labelledpeptide-MHC multimers

    DEFF Research Database (Denmark)

    Lyngaa, Rikke Birgitte; Bentzen, Amalie Kai; Overgaard, A. Julie

    2016-01-01

    applying a novel technology where the selection of MHC-multimer binding T cells is followed by amplification and sequencing of MHC multimer-associated DNA barcodes revealing their recognition. This technique enables simultaneous detection of >1000 specificities. Identifying post translational modifications...

  17. Deleterious impact of feto-maternal MHC compatibility on the success of pregnancy in a macaque model.

    Science.gov (United States)

    Aarnink, Alice; Mee, Edward T; Savy, Nicolas; Congy-Jolivet, Nicolas; Rose, Nicola J; Blancher, Antoine

    2014-02-01

    The impact of feto-maternal histocompatibility on reproduction has inspired long-lasting debates. However, after the review of numerous articles, the impact of HLA allele sharing within couples on fecundity remains questionable. We decided to explore the impact of major histocompatibility complex (MHC) feto-maternal compatibility on reproduction in a cynomolgus macaque facility composed of animals of Mauritian descent. The Mauritian-derived macaque population presents a very restricted MHC polymorphism (only seven founding haplotypes) due to a strong founding bottleneck effect. The MHC polymorphism was investigated in 237 trios (male, female and offspring) using 17 microsatellite markers distributed across the MHC. Haplotypes were confirmed by segregation analysis. We evaluated the relative frequencies of MHC-compatible and MHC-semi-compatible offspring with the mothers. Among the 237 trios, we selected 42 trios for which the identity of the father is certain and for which the theoretical probabilities of fully compatible and semi-compatible offspring were equal. We found 11 offspring fully compatible and 31 offspring semi-compatible with their respective mother. The observed proportions were clearly outside the interval of confidence of 99 % and therefore most probably resulted from a selection of the semi-compatible offspring during pregnancy. We concluded that MHC fully compatible cynomolgus macaque offspring have a selective survival disadvantage in comparison with offspring inheriting a paternal MHC haplotype differing from maternal haplotypes.

  18. MHC class IIB Exon 2 Polymorphism in the Grey Partridge (Perdix perdix) is shaped by selection, recombination and gene conversion

    Czech Academy of Sciences Publication Activity Database

    Promerová, Marta; Králová, Tereza; Bryjová, Anna; Albrecht, Tomáš; Bryja, Josef

    2013-01-01

    Roč. 8, č. 7 (2013), e69135 E-ISSN 1932-6203 R&D Projects: GA ČR GA206/08/1281 Institutional support: RVO:68081766 Keywords : major histocompatibility complex (MHC) * snipe Gallinago-media * Class-I genes * minimal-essential-MHC Subject RIV: EG - Zoology Impact factor: 3.534, year: 2013

  19. Heavy flavours

    CERN Document Server

    Buras, Andrzej J

    1998-01-01

    This volume is a collection of review articles on the most outstanding topics in heavy flavour physics. All the authors have made significant contributions to this field. The book reviews in detail the theoretical structure of heavy flavour physics and confronts the Standard Model and some of its extensions with existing experimental data.This new edition covers new trends and ideas and includes the latest experimental information. Compared to the previous edition interesting new activities are included and some of the key contributions are updated. Particular attention is paid to the discover

  20. One-pot, mix-and-read peptide-MHC tetramers

    DEFF Research Database (Denmark)

    Leisner, Christian Valdemar Vinge; Loeth, Nina; Lamberth, Kasper

    2008-01-01

    BACKGROUND: Cytotoxic T Lymphocytes (CTL) recognize complexes of peptide ligands and Major Histocompatibility Complex (MHC) class I molecules presented at the surface of Antigen Presenting Cells (APC). Detection and isolation of CTL's are of importance for research on CTL immunity, and development...... molecules can be refolded in vitro, tetramerized with streptavidin, and used for specific T cell staining-all in a one-pot reaction without any intervening purification steps. CONCLUSIONS/SIGNIFICANCE: We have developed an efficient "one-pot, mix-and-read" strategy for peptide-MHC tetramer generation...

  1. Predicting peptides binding to MHC class II molecules using multi-objective evolutionary algorithms

    Directory of Open Access Journals (Sweden)

    Feng Lin

    2007-11-01

    Full Text Available Abstract Background Peptides binding to Major Histocompatibility Complex (MHC class II molecules are crucial for initiation and regulation of immune responses. Predicting peptides that bind to a specific MHC molecule plays an important role in determining potential candidates for vaccines. The binding groove in class II MHC is open at both ends, allowing peptides longer than 9-mer to bind. Finding the consensus motif facilitating the binding of peptides to a MHC class II molecule is difficult because of different lengths of binding peptides and varying location of 9-mer binding core. The level of difficulty increases when the molecule is promiscuous and binds to a large number of low affinity peptides. In this paper, we propose two approaches using multi-objective evolutionary algorithms (MOEA for predicting peptides binding to MHC class II molecules. One uses the information from both binders and non-binders for self-discovery of motifs. The other, in addition, uses information from experimentally determined motifs for guided-discovery of motifs. Results The proposed methods are intended for finding peptides binding to MHC class II I-Ag7 molecule – a promiscuous binder to a large number of low affinity peptides. Cross-validation results across experiments on two motifs derived for I-Ag7 datasets demonstrate better generalization abilities and accuracies of the present method over earlier approaches. Further, the proposed method was validated and compared on two publicly available benchmark datasets: (1 an ensemble of qualitative HLA-DRB1*0401 peptide data obtained from five different sources, and (2 quantitative peptide data obtained for sixteen different alleles comprising of three mouse alleles and thirteen HLA alleles. The proposed method outperformed earlier methods on most datasets, indicating that it is well suited for finding peptides binding to MHC class II molecules. Conclusion We present two MOEA-based algorithms for finding motifs

  2. Axotomy induces MHC class I antigen expression on rat nerve cells

    DEFF Research Database (Denmark)

    Maehlen, J; Schröder, H D; Klareskog, L

    1988-01-01

    Immunomorphological staining demonstrates that class I major histocompatibility complex (MHC)-coded antigen expression can be selectively induced on otherwise class I-negative rat nerve cells by peripheral axotomy. Induction of class I as well as class II antigen expression was simultaneously seen...... on non-neural cells in the immediate vicinity of the injured nerve cells. As nerve regeneration after axotomy includes growth of new nerve cell processes and formation of new nerve cell contacts, the present findings raise the question of a role for MHC-coded molecules in cell-cell interactions during...... nerve cell growth....

  3. Horse cDNA clones encoding two MHC class I genes

    Energy Technology Data Exchange (ETDEWEB)

    Barbis, D.P.; Maher, J.K.; Stanek, J.; Klaunberg, B.A.; Antczak, D.F.

    1994-12-31

    Two full-length clones encoding MHC class I genes were isolated by screening a horse cDNA library, using a probe encoding in human HLA-A2.2Y allele. The library was made in the pcDNA1 vector (Invitrogen, San Diego, CA), using mRNA from peripheral blood lymphocytes obtained from a Thoroughbred stallion (No. 0834) homozygous for a common horse MHC haplotype (ELA-A2, -B2, -D2; Antczak et al. 1984; Donaldson et al. 1988). The clones were sequenced, using SP6 and T7 universal primers and horse-specific oligonucleotides designed to extend previously determined sequences.

  4. A Novel Therapeutic Vaccine for Metastatic Mammary Carcinoma: Focusing MHC/Peptide Complexes to Lipid Rafts

    Science.gov (United States)

    2006-11-01

    reportable outcomes). Briefly, the T cell lymphoma EL4 and the immortalized fibroblast cell line DAP (both expressing ova) were used to measure...and Use Committee. Cells , transfections, and antibodies B16.BL6 8.2, A20, EL4 and EL4 /ova were cultured as described (20-22). NIH3T3 cells were...types can donate MHC class I molecules to DC. To determine if the levels of MHC class I on the donor cell affected the efficiency of transfer, EL4 /ova

  5. Additional file 4: of MHC class II expression and potential antigen-presenting cells in the retina during experimental autoimmune uveitis

    OpenAIRE

    Lipski, Deborah; Dewispelaere, RÊmi; Foucart, Vincent; Caspers, Laure; Defrance, Matthieu; Bruyns, Catherine; Willermain, François

    2017-01-01

    Figure S4. MHC class II expression in the retina during classical EAU. Three weeks after immunization, eye cryosections were prepared and stained for MHC class II (green) and IBA1 (red) or endoglin (magenta) detection. Cell nuclei were stained with Hoechst (blue). Each picture was chosen as representative of an experiment conducted on six or more animals. A. MHC class II and IBA1 expression. B. MHC class II and endoglin expression. (PPTX 7276 kb)

  6. Real-time, high-throughput measurements of peptide-MHC-I dissociation using a scintillation proximity assay

    DEFF Research Database (Denmark)

    Harndahl, Mikkel; Rasmussen, Michael; Røder, Gustav Andreas

    2011-01-01

    and it is well suited for high-throughput screening. To exemplify this, we screened a panel of 384 high-affinity peptides binding to the MHC class I molecule, HLA-A*02:01, and observed the rates of dissociation that ranged from 0.1h to 46h depending on the peptide used.......Efficient presentation of peptide-MHC class I complexes to immune T cells depends upon stable peptide-MHC class I interactions. Theoretically, determining the rate of dissociation of a peptide-MHC class I complexes is straightforward; in practical terms, however, generating the accurate and closely...... timed data needed to determine the rate of dissociation is not simple. Ideally, one should use a homogenous assay involving an inexhaustible and label-free assay principle. Here, we present a homogenous, high-throughput peptide-MHC class I dissociation assay, which by and large fulfill these ideal...

  7. Constitutive MHC class I molecules negatively regulate TLR-triggered inflammatory responses via the Fps-SHP-2 pathway.

    Science.gov (United States)

    Xu, Sheng; Liu, Xingguang; Bao, Yan; Zhu, Xuhui; Han, Chaofeng; Zhang, Peng; Zhang, Xuemin; Li, Weihua; Cao, Xuetao

    2012-04-22

    The molecular mechanisms that fine-tune Toll-like receptor (TLR)-triggered innate inflammatory responses remain to be fully elucidated. Major histocompatibility complex (MHC) molecules can mediate reverse signaling and have nonclassical functions. Here we found that constitutively expressed membrane MHC class I molecules attenuated TLR-triggered innate inflammatory responses via reverse signaling, which protected mice from sepsis. The intracellular domain of MHC class I molecules was phosphorylated by the kinase Src after TLR activation, then the tyrosine kinase Fps was recruited via its Src homology 2 domain to phosphorylated MHC class I molecules. This led to enhanced Fps activity and recruitment of the phosphatase SHP-2, which interfered with TLR signaling mediated by the signaling molecule TRAF6. Thus, constitutive MHC class I molecules engage in crosstalk with TLR signaling via the Fps-SHP-2 pathway and control TLR-triggered innate inflammatory responses.

  8. Leukemia prevention and long-term survival of AKR mice transplanted with MHC-matched or MHC-mismatched bone marrow

    International Nuclear Information System (INIS)

    Longley, R.E.; Good, R.A.

    1986-01-01

    The current studies were designed to evaluate the effectiveness of marrow transplantation within and outside the major histocompatibility complex (MHC) on the long-term survival and occurrence of spontaneous leukemia in AKR mice. AKR mice, which were lethally irradiated and received MHC-matched marrow from CBA/J mice (CBA----AKR), never developed leukemia and were alive and remained healthy for up to 280 days post-transplant. These long-term surviving chimeras possessed substantial immune vigor when both cell-mediated and humoral responses were tested. Lethally irradiated AKR mice, which had received MHC-mismatched marrow (anti-Thy-1.2 treated or nontreated) from C57BL/6J mice (B6----AKR), never developed leukemia and survived up to 170 days post-transplant. However, both groups of these chimeras began dying 180 to 270 days post-transplant due to a disease process which could not be readily identified. Histological analysis of B6----AKR chimeras revealed severe lymphoid cell depletion in thymus and spleen; however, none of these chimeras exhibited classical features of acute graft versus host disease. Concanavalin A mitogenesis, primary antibody responses to sheep red blood cells and the production of interleukin 2 (IL-2) were suppressed in B6----AKR chimeras. IL-2 treatment of B6----AKR chimeras was shown to partially correct these deficiencies without stimulating mixed lymphocyte responsiveness to donor or host lymphocytes. These studies indicate that the use of MHC-mismatched marrow for the prevention of spontaneous AKR leukemia may rely on augmentative IL-2 therapy for complete immune reconstitution of leukemia-free chimeras

  9. Immunization with MHC class I-negative but not -positive HPV16-associated tumour cells inhibits growth of MHC class I-negative tumours

    Czech Academy of Sciences Publication Activity Database

    Reiniš, Milan; Šímová, Jana; Indrová, Marie; Bieblová, Jana; Přibylová, Hana; Moravcová, Simona; Jandlová, Táňa; Bubeník, Jan

    2007-01-01

    Roč. 30, č. 4 (2007), s. 1011-1017 ISSN 1019-6439 R&D Projects: GA MZd NR7807 EU Projects: European Commission(XE) 18933 - CLINIGENE Grant - others:Liga proti rakovině, Praha(CZ) XX Institutional research plan: CEZ:AV0Z50520514 Keywords : HPV16 * MHC class I-deficient tumours * immunologic crossreaction Subject RIV: EB - Genetics ; Molecular Biology Impact factor: 2.295, year: 2007

  10. CHAIN 2

    International Nuclear Information System (INIS)

    Bailey, D.

    1998-04-01

    The Second Processing Chain (CHAIN2) consists of a suite of ten programs which together provide a full local analysis of the bulk plasma physics within the JET Tokamak. In discussing these ten computational models this report is intended to fulfil two broad purposes. Firstly it is meant to be used as a reference source for any user of CHAIN2 data, and secondly it provides a basic User Manual sufficient to instruct anyone in running the CHAIN2 suite of codes. In the main report text each module is described in terms of its underlying physics and any associated assumptions or limitations, whilst deliberate emphasis is put on highlighting the physics and mathematics of the calculations required in deriving each individual datatype in the standard module PPF output. In fact each datatype of the CHAIN2 PPF output listed in Appendix D is cross referenced to the point in the main text where its evaluation is discussed. An effort is made not only to give the equation used to derive a particular data profile but also to explicitly define which external data sources are involved in the computational calculation

  11. Heavy quarks

    International Nuclear Information System (INIS)

    Khoze, V.A.

    1983-10-01

    We discuss the results accumulated during the last five years in heavy quark physics and try to draw a simple general picture of the present situation. The survey is based on a unified point of view resulting from quantum chromodynamics. (orig.)

  12. Peptide motifs of the single dominantly expressed class I molecule explain the striking MHC-determined response to Rous sarcoma virus in chickens

    DEFF Research Database (Denmark)

    Wallny, Hans-Joachim; Avila, David; Hunt, Lawrence G.

    2006-01-01

    Compared with the MHC of typical mammals, the chicken MHC is smaller and simpler, with only two class I genes found in the B12 haplotype. We make five points to show that there is a single-dominantly expressed class I molecule that can have a strong effect on MHC function. First, we find only one...

  13. Crystal structure of a Gammadelta T-cell Receptor Specific for the Human MHC class I Homolog MICA

    Energy Technology Data Exchange (ETDEWEB)

    B Xu; J Pizarro; M Holmes; C McBeth; V Groh; T Spies; R Strong

    2011-12-31

    {gamma}{delta} T cells play important roles in bridging innate and adaptive immunity, but their recognition mechanisms remain poorly understood. Human {gamma}{delta} T cells of the V{sub {delta}}1 subset predominate in intestinal epithelia and respond to MICA and MICB (MHC class I chain-related, A and B; MIC) self-antigens, mediating responses to tumorigenesis or viral infection. The crystal structure of an MIC-reactive V{sub {delta}}1 {gamma}{delta} T-cell receptor (TCR) showed expected overall structural homology to antibodies, {alpha}{beta}, and other {gamma}{delta} TCRs, but complementary determining region conformations and conservation of V{sub {delta}}1 use revealed an uncharacteristically flat potential binding surface. MIC, likewise, serves as a ligand for the activating immunoreceptor natural killer group 2, D (NKG2D), also expressed on {gamma}{delta} T cells. Although MIC recognition drives both the TCR-dependent stimulatory and NKG2D-dependent costimulatory signals necessary for activation, interaction analyses showed that MIC binding by the two receptors was mutually exclusive. Analysis of relative binding kinetics suggested sequential recognition, defining constraints for the temporal organization of {gamma}{delta} T-cell/target cell interfaces.

  14. Crystal structure of a gammadelta T-cell receptor specific for the human MHC class I homolog MICA.

    Science.gov (United States)

    Xu, Bin; Pizarro, Juan C; Holmes, Margaret A; McBeth, Christine; Groh, Veronika; Spies, Thomas; Strong, Roland K

    2011-02-08

    γδ T cells play important roles in bridging innate and adaptive immunity, but their recognition mechanisms remain poorly understood. Human γδ T cells of the V(δ)1 subset predominate in intestinal epithelia and respond to MICA and MICB (MHC class I chain-related, A and B; MIC) self-antigens, mediating responses to tumorigenesis or viral infection. The crystal structure of an MIC-reactive V(δ)1 γδ T-cell receptor (TCR) showed expected overall structural homology to antibodies, αβ, and other γδ TCRs, but complementary determining region conformations and conservation of V(δ)1 use revealed an uncharacteristically flat potential binding surface. MIC, likewise, serves as a ligand for the activating immunoreceptor natural killer group 2, D (NKG2D), also expressed on γδ T cells. Although MIC recognition drives both the TCR-dependent stimulatory and NKG2D-dependent costimulatory signals necessary for activation, interaction analyses showed that MIC binding by the two receptors was mutually exclusive. Analysis of relative binding kinetics suggested sequential recognition, defining constraints for the temporal organization of γδ T-cell/target cell interfaces.

  15. Exhaustion of CTL memory and recrudescence of viremia in lymphocytic choriomeningitis virus-infected MHC class II-deficient mice and B cell-deficient mice

    DEFF Research Database (Denmark)

    Thomsen, Allan Randrup; Johansen, J; Marker, O

    1996-01-01

    To study the contribution of CD4+ T cells and B cells to antiviral immunity and long term virus control, MHC class II-deficient and B cell-deficient mice were infected with lymphocytic choriomeningitis virus. In class II-deficient mice, which lack CD4+ T cells, the primary CTL response is virtually...... this phenomenon could reflect participation of B cells and/or Abs in long term virus control, similar experiments were performed with mice that do not have mature B cells because of a disrupted membrane exon of the mu chain gene. In these mice, the cell-mediated immune response was slightly delayed, but transient...... and that in their absence, the virus-specific CTL potential becomes exhausted. Together our results indicate that while CD8+ cells play a dominant role in acute virus control, all three major components of the immune system are required for long term virus control....

  16. Heavy flavours: theory summary

    OpenAIRE

    Corcella, Gennaro

    2005-01-01

    I summarize the theory talks given in the Heavy Flavours Working Group. In particular, I discuss heavy-flavour parton distribution functions, threshold resummation for heavy-quark production, progress in fragmentation functions, quarkonium production, heavy-meson hadroproduction.

  17. Tetraspan microdomains distinct from lipid rafts enrich select peptide-MHC class II complexes

    Czech Academy of Sciences Publication Activity Database

    Kropshofer, H.; Spindeldreher, S.; Rohn, T. A.; Platania, N.; Grygar, C.; Daniel, N.; Wolpl, A.; Langen, H.; Hořejší, Václav; Vogt, A. B.

    2002-01-01

    Roč. 3, č. 1 (2002), s. 61-68 ISSN 1529-2908 Institutional research plan: CEZ:AV0Z5052915 Keywords : MHC II * tetraspan microdomains * peptide presentation Subject RIV: EB - Genetics ; Molecular Biology Impact factor: 27.868, year: 2002

  18. MHC class II B diversity in blue tits: a preliminary study.

    Science.gov (United States)

    Aguilar, Juan Rivero-de; Schut, Elske; Merino, Santiago; Martínez, Javier; Komdeur, Jan; Westerdahl, Helena

    2013-07-01

    In this study, we partly characterize major histocompatibility complex (MHC) class II B in the blue tit (Cyanistes caeruleus). A total of 22 individuals from three different European locations: Spain, The Netherlands, and Sweden were screened for MHC allelic diversity. The MHC genes were investigated using both PCR-based methods and unamplified genomic DNA with restriction fragment length polymorphism (RFLP) and southern blots. A total of 13 different exon 2 sequences were obtained independently from DNA and/or RNA, thus confirming gene transcription and likely functionality of the genes. Nine out of 13 alleles were found in more than one country, and two alleles appeared in all countries. Positive selection was detected in the region coding for the peptide binding region (PBR). A maximum of three alleles per individual was detected by sequencing and the RFLP pattern consisted of 4-7 fragments, indicating a minimum number of 2-4 loci per individual. A phylogenetic analysis, demonstrated that the blue tit sequences are divergent compared to sequences from other passerines resembling a different MHC lineage than those possessed by most passerines studied to date.

  19. Species-specific evolution of class I MHC genes in iguanas (order: Squamata; subfamily: Iguaninae).

    Science.gov (United States)

    Glaberman, Scott; Caccone, Adalgisa

    2008-07-01

    Over the last few decades, the major histocompatibility complex (MHC) has emerged as a model for understanding the influence of natural selection on genetic diversity in populations as well as for investigating the genetic basis of host resistance to pathogens. However, many vertebrate taxa remain underrepresented in the field of MHC research, preventing its application to studies of disease, evolution, and conservation genetics in these groups. This is particularly true for squamates, which are by far the most diversified order of non-avian reptiles but have not been the subject of any recent MHC studies. In this paper, we present MHC class I complementary DNA data from three squamate species in the subfamily Iguaninae (iguanas): the Galápagos marine iguana (Amblyrhynchus cristatus), the Galápagos land iguana (Conolophus subcristatus), and the green iguana (Iguana iguana). All sequences obtained are related to the few published class I genes from other squamates. There is evidence for multiple loci in each species, and the conserved alpha-3 domain appears to be evolving in a species-specific manner. Conversely, there is some indication of shared polymorphism between species in the peptide-binding alpha-1 and alpha-2 domains, suggesting that these two regions have different phylogenetic histories. The great similarity between alpha-3 sequences in marine iguanas in particular suggests that concerted evolution is acting to homogenize class I loci within species. However, while less likely, the data are also compatible with a birth and death model of evolution.

  20. AN MHC class I immune evasion gene of Marek's disease virus

    Science.gov (United States)

    Marek's disease virus (MDV) is a widespread a-herpesvirus of chickens that causes T cell tumors. Acute, but not latent, MDV infection has previously been shown to lead to downregulation of cell-surface MHC class I (Virology 282:198–205 (2001)), but the gene(s) involved have not been identified. Here...

  1. 75 FR 28685 - Colonial Bankshares, MHC, Vineland, NJ; Approval of Conversion Application

    Science.gov (United States)

    2010-05-21

    ... DEPARTMENT OF THE TREASURY Office of Thrift Supervision [AC-41: OTS Nos. 04983, H-3879, and H-4714... May 14, 2010, the Office of Thrift Supervision approved the application of Colonial Bankshares, MHC, and Colonial Bank, Vineland, New Jersey, to convert to the stock form of organization. Copies of the...

  2. 75 FR 28685 - Oritani Financial Corp., MHC, Township of Washington, NJ; Approval of Conversion Application

    Science.gov (United States)

    2010-05-21

    ... DEPARTMENT OF THE TREASURY Office of Thrift Supervision [AC-39: OTS Nos. H-2944 and H-4701... hereby given that on May 10, 2010, the Office of Thrift Supervision approved the application of Oritani Financial Corp., MHC, and Oritani Bank, Township of Washington, New Jersey, to convert to the stock form of...

  3. Evolution of MHC-based technologies used for detection of antigen-responsive T cells

    DEFF Research Database (Denmark)

    Bentzen, Amalie Kai; Hadrup, Sine Reker

    2017-01-01

    T cell-mediated recognition of peptide-major histocompatibility complex (pMHC) class I and II molecules is crucial for the control of intracellular pathogens and cancer, as well as for stimulation and maintenance of efficient cytotoxic responses. Such interactions may also play a role in the deve...

  4. MHC class I epitope binding prediction trained on small data sets

    DEFF Research Database (Denmark)

    Lundegaard, Claus; Nielsen, Morten; Lamberth, K.

    2004-01-01

    The identification of potential T-cell epitopes is important for development of new human or vetenary vaccines, both considering single protein/subunit vaccines, and for epitope/peptide vaccines as such. The highly diverse MHC class I alleles bind very different peptides, and accurate binding pre...... in situations where only very limited data are available for training....

  5. MHC class II-assortative mate choice in European badgers (Meles meles)

    NARCIS (Netherlands)

    Sin, Yung Wa; Annavi, Geetha; Newman, Chris; Buesching, Christina D.; Burke, Terry; Macdonald, David W.; Dugdale, Hannah

    The major histocompatibility complex (MHC) plays a crucial role in the immune system, and in some species, it is a target by which individuals choose mates to optimize the fitness of their offspring, potentially mediated by olfactory cues. Under the genetic compatibility hypothesis, individuals are

  6. MHC class I dowregulation, tumour escape from immune surveillance and design of therapeutic strategies

    Czech Academy of Sciences Publication Activity Database

    Bubeník, Jan

    2005-01-01

    Roč. 51, č. 1 (2005), s. 1-2 ISSN 0015-5500 R&D Projects: GA ČR GA301/04/0492; GA MZd NR7807 Institutional research plan: CEZ:AV0Z50520514 Keywords : MHC class I * immune surveillance * immunotherapy Subject RIV: EC - Immunology Impact factor: 0.719, year: 2005

  7. Variation in MHC class II B genes in marbled murrelets: implications for delineating conservation units

    Science.gov (United States)

    C. Vásquez-Carrillo; V. Friesen; L. Hall; M.Z. Peery

    2013-01-01

    Conserving genetic variation is critical for maintaining the evolutionary potential and viability of a species. Genetic studies seeking to delineate conservation units, however, typically focus on characterizing neutral genetic variation and may not identify populations harboring local adaptations. Here, variation at two major histocompatibility complex (MHC) class II...

  8. Mechanical Stress Downregulates MHC Class I Expression on Human Cancer Cell Membrane

    KAUST Repository

    La Rocca, Rosanna; Tallerico, Rossana; Talib Hassan, Almosawy; Das, Gobind; Tadepally, Lakshmikanth; Matteucci, Marco; Liberale, Carlo; Mesuraca, Maria; Scumaci, Domenica; Gentile, Francesco; Cojoc, Gheorghe; Perozziello, Gerardo; Ammendolia, Antonio; Gallo, Adriana; Kä rre, Klas; Cuda, Giovanni; Candeloro, Patrizio; Di Fabrizio, Enzo M.; Carbone, Ennio

    2014-01-01

    bar (1 bar = 100.000 Pascal), depending on the devices used. Moreover, Raman spectroscopy analysis, after mechanical treatment, in the range between 700–1800 cm−1, indicated a relative concentration variation of MHC class I. PCA analysis was also

  9. Limitations of Ab Initio Predictions of Peptide Binding to MHC Class II Molecules

    DEFF Research Database (Denmark)

    Zhang, Hao; Lund, Ole; Nielsen, Morten

    2010-01-01

    potentials derived from the analysis of known protein structures; energetic evaluation of different peptide snapshots in a molecular dynamics simulation; and direct analysis of contacts made in known 3D structures of peptide:MHC complexes. These methods are ab initio in that they require structural data...

  10. Peptide-MHC class I stability is a stronger predictor of CTL immunogenicity than peptide affinity

    DEFF Research Database (Denmark)

    Harndahl, Mikkel Nors; Rasmussen, Michael; Nielsen, Morten

    2012-01-01

    Peptide-MHC class I stability is a stronger predictor of CTL immunogenicity than peptide affinity Mikkel Harndahla, Michael Rasmussena, Morten Nielsenb, Soren Buusa,∗ a Laboratory of Experimental Immunology, Faculty of Health Sciences, University of Copenhagen, Denmark b Center for Biological Seq...... al., 2007. J. Immunol. 178, 7890–7901. doi:10.1016/j.molimm.2012.02.025...

  11. Red Queen Processes Drive Positive Selection on Major Histocompatibility Complex (MHC Genes.

    Directory of Open Access Journals (Sweden)

    Maciej Jan Ejsmond

    2015-11-01

    Full Text Available Major Histocompatibility Complex (MHC genes code for proteins involved in the incitation of the adaptive immune response in vertebrates, which is achieved through binding oligopeptides (antigens of pathogenic origin. Across vertebrate species, substitutions of amino acids at sites responsible for the specificity of antigen binding (ABS are positively selected. This is attributed to pathogen-driven balancing selection, which is also thought to maintain the high polymorphism of MHC genes, and to cause the sharing of allelic lineages between species. However, the nature of this selection remains controversial. We used individual-based computer simulations to investigate the roles of two phenomena capable of maintaining MHC polymorphism: heterozygote advantage and host-pathogen arms race (Red Queen process. Our simulations revealed that levels of MHC polymorphism were high and driven mostly by the Red Queen process at a high pathogen mutation rate, but were low and driven mostly by heterozygote advantage when the pathogen mutation rate was low. We found that novel mutations at ABSs are strongly favored by the Red Queen process, but not by heterozygote advantage, regardless of the pathogen mutation rate. However, while the strong advantage of novel alleles increased the allele turnover rate, under a high pathogen mutation rate, allelic lineages persisted for a comparable length of time under Red Queen and under heterozygote advantage. Thus, when pathogens evolve quickly, the Red Queen is capable of explaining both positive selection and long coalescence times, but the tension between the novel allele advantage and persistence of alleles deserves further investigation.

  12. Improved methods for predicting peptide binding affinity to MHC class II molecules.

    Science.gov (United States)

    Jensen, Kamilla Kjaergaard; Andreatta, Massimo; Marcatili, Paolo; Buus, Søren; Greenbaum, Jason A; Yan, Zhen; Sette, Alessandro; Peters, Bjoern; Nielsen, Morten

    2018-01-06

    Major histocompatibility complex class II (MHC-II) molecules are expressed on the surface of professional antigen-presenting cells where they display peptides to T helper cells, which orchestrate the onset and outcome of many host immune responses. Understanding which peptides will be presented by the MHC-II molecule is therefore important for understanding the activation of T helper cells and can be used to identify T-cell epitopes. We here present updated versions of two MHC-II-peptide binding affinity prediction methods, NetMHCII and NetMHCIIpan. These were constructed using an extended data set of quantitative MHC-peptide binding affinity data obtained from the Immune Epitope Database covering HLA-DR, HLA-DQ, HLA-DP and H-2 mouse molecules. We show that training with this extended data set improved the performance for peptide binding predictions for both methods. Both methods are publicly available at www.cbs.dtu.dk/services/NetMHCII-2.3 and www.cbs.dtu.dk/services/NetMHCIIpan-3.2. © 2018 John Wiley & Sons Ltd.

  13. Tolerance to MHC class II disparate allografts through genetic modification of bone marrow

    Science.gov (United States)

    Jindra, Peter T.; Tripathi, Sudipta; Tian, Chaorui; Iacomini, John; Bagley, Jessamyn

    2012-01-01

    Induction of molecular chimerism through genetic modification of bone marrow is a powerful tool for the induction of tolerance. Here we demonstrate for the first time that expression of an allogeneic MHC class II gene in autologous bone marrow cells, resulting in a state of molecular chimerism, induces tolerance to MHC class II mismatched skin grafts, a stringent test of transplant tolerance. Reconstitution of recipients with syngeneic bone marrow transduced with retrovirus encoding H-2I-Ab (I-Ab) resulted the long-term expression of the retroviral gene product on the surface of MHC class II-expressing bone marrow derived cell types. Mechanistically, tolerance was maintained by the presence of regulatory T cells, which prevented proliferation and cytokine production by alloreactive host T cells. Thus, the introduction of MHC class II genes into bone marrow derived cells through genetic engineering results in tolerance. These results have the potential to extend the clinical applicability of molecular chimerism for tolerance induction. PMID:22833118

  14. Establishment of a quantitative ELISA capable of determining peptide - MHC class I interaction

    DEFF Research Database (Denmark)

    Sylvester-Hvid, C; Kristensen, N; Blicher, T

    2002-01-01

    dependent manner. Here, we exploit the availability of these molecules to generate a quantitative ELISA-based assay capable of measuring the affinity of the interaction between peptide and MHC-I. This assay is simple and sensitive, and one can easily envisage that the necessary reagents, standards...

  15. Thymic repopulation following intrathymic injection of mouse bone marrow cells in MHC matched and mismatched recipients

    International Nuclear Information System (INIS)

    Chervenak, R.

    1986-01-01

    T cell precursors (pre-T cells) have traditionally been detected by their ability to repopulate the thymus of heavily irradiated mice following intravenous injection. Recently, Goldschneider et. al. developed an assay system which involves the direct injection of pre-T cells into the thymus. The authors used this technique to evaluate the ability of bone marrow cells to repopulate thymuses in various donor-host strain combinations. Sub-lethally irradiated (600R) mice were injected intrathymically with 2 x 10 6 bone marrow cells which differed from the recipient with respect to their Thy 1 allotype. The percentage of thymus cells expressing either the donor or recipient type Thy 1 marker was determined 14 to 21 days after injection. These experiments showed that in MHC matched donor-host combinations (AKR/cum → AKR/J and CBA/J → AKR/J), cells derived from the donor inoculum accounted for 40% to 75% of the total thymus population. MHC mismatched donor-host combinations (C57BL/6J → AKR/J and Balb/c → AKR/J) resulted in significantly less donor-type repopulation of the thymus. In these cases, donor repopulation typically ranged from 0% to 4%. The ability of the pre-T cells detected by intrathymic injection to proliferate in the thymic environment, therefore, appears to be influenced by the MHC. This may reflect commitment of pre-T cells to MHC haplotype recognition prior to their migration to the thymus

  16. The MHC locus and genetic susceptibility to autoimmune and infectious diseases

    NARCIS (Netherlands)

    Matzaraki, Vasiliki; Kumar, Vinod; Wijmenga, Cisca; Zhernakova, Alexandra

    2017-01-01

    In the past 50 years, variants in the major histocompatibility complex (MHC) locus, also known as the human leukocyte antigen (HLA), have been reported as major risk factors for complex diseases. Recent advances, including large genetic screens, imputation, and analyses of non-additive and epistatic

  17. NetMHCpan, a method for MHC class I binding prediction beyond humans

    DEFF Research Database (Denmark)

    Hoof, Ilka; Peters, B; Sidney, J

    2009-01-01

    molecules. We show that the NetMHCpan-2.0 method can accurately predict binding to uncharacterized HLA molecules, including HLA-C and HLA-G. Moreover, NetMHCpan-2.0 is demonstrated to accurately predict peptide binding to chimpanzee and macaque MHC class I molecules. The power of NetMHCpan-2.0 to guide...

  18. MHC class II DQB diversity in the Japanese black bear, Ursus thibetanus japonicus.

    Science.gov (United States)

    Yasukochi, Yoshiki; Kurosaki, Toshifumi; Yoneda, Masaaki; Koike, Hiroko; Satta, Yoko

    2012-11-29

    The major histocompatibility complex (MHC) genes are one of the most important genetic systems in the vertebrate immune response. The diversity of MHC genes may directly influence the survival of individuals against infectious disease. However, there has been no investigation of MHC diversity in the Asiatic black bear (Ursus thibetanus). Here, we analyzed 270-bp nucleotide sequences of the entire exon 2 region of the MHC DQB gene by using 188 samples from the Japanese black bear (Ursus thibetanus japonicus) from 12 local populations. Among 185 of 188 samples, we identified 44 MHC variants that encoded 31 different amino acid sequences (allotypes) and one putative pseudogene. The phylogenetic analysis suggests that MHC variants detected from the Japanese black bear are derived from the DQB locus. One of the 31 DQB allotypes, Urth-DQB*01, was found to be common to all local populations. Moreover, this allotype was shared between the black bear on the Asian continent and the Japanese black bear, suggesting that Urth-DQB*01 might have been maintained in the ancestral black bear population for at least 300,000 years. Our findings, from calculating the ratio of non-synonymous to synonymous substitutions, indicate that balancing selection has maintained genetic variation of peptide-binding residues at the DQB locus of the Japanese black bear. From examination of genotype frequencies among local populations, we observed a considerably lower level of observed heterozygosity than expected. The low level of observed heterozygosity suggests that genetic drift reduced DQB diversity in the Japanese black bear due to a bottleneck event at the population or species level. The decline of DQB diversity might have been accelerated by the loss of rare variants that have been maintained by negative frequency-dependent selection. Nevertheless, DQB diversity of the black bear appears to be relatively high compared with some other endangered mammalian species. This result suggests that

  19. MHC class II DQB diversity in the Japanese black bear, Ursus thibetanus japonicus

    Science.gov (United States)

    2012-01-01

    Background The major histocompatibility complex (MHC) genes are one of the most important genetic systems in the vertebrate immune response. The diversity of MHC genes may directly influence the survival of individuals against infectious disease. However, there has been no investigation of MHC diversity in the Asiatic black bear (Ursus thibetanus). Here, we analyzed 270-bp nucleotide sequences of the entire exon 2 region of the MHC DQB gene by using 188 samples from the Japanese black bear (Ursus thibetanus japonicus) from 12 local populations. Results Among 185 of 188 samples, we identified 44 MHC variants that encoded 31 different amino acid sequences (allotypes) and one putative pseudogene. The phylogenetic analysis suggests that MHC variants detected from the Japanese black bear are derived from the DQB locus. One of the 31 DQB allotypes, Urth-DQB*01, was found to be common to all local populations. Moreover, this allotype was shared between the black bear on the Asian continent and the Japanese black bear, suggesting that Urth-DQB*01 might have been maintained in the ancestral black bear population for at least 300,000 years. Our findings, from calculating the ratio of non-synonymous to synonymous substitutions, indicate that balancing selection has maintained genetic variation of peptide-binding residues at the DQB locus of the Japanese black bear. From examination of genotype frequencies among local populations, we observed a considerably lower level of observed heterozygosity than expected. Conclusions The low level of observed heterozygosity suggests that genetic drift reduced DQB diversity in the Japanese black bear due to a bottleneck event at the population or species level. The decline of DQB diversity might have been accelerated by the loss of rare variants that have been maintained by negative frequency-dependent selection. Nevertheless, DQB diversity of the black bear appears to be relatively high compared with some other endangered mammalian

  20. MHC class II DQB diversity in the Japanese black bear, Ursus thibetanus japonicus

    Directory of Open Access Journals (Sweden)

    Yasukochi Yoshiki

    2012-11-01

    Full Text Available Abstract Background The major histocompatibility complex (MHC genes are one of the most important genetic systems in the vertebrate immune response. The diversity of MHC genes may directly influence the survival of individuals against infectious disease. However, there has been no investigation of MHC diversity in the Asiatic black bear (Ursus thibetanus. Here, we analyzed 270-bp nucleotide sequences of the entire exon 2 region of the MHC DQB gene by using 188 samples from the Japanese black bear (Ursus thibetanus japonicus from 12 local populations. Results Among 185 of 188 samples, we identified 44 MHC variants that encoded 31 different amino acid sequences (allotypes and one putative pseudogene. The phylogenetic analysis suggests that MHC variants detected from the Japanese black bear are derived from the DQB locus. One of the 31 DQB allotypes, Urth-DQB*01, was found to be common to all local populations. Moreover, this allotype was shared between the black bear on the Asian continent and the Japanese black bear, suggesting that Urth-DQB*01 might have been maintained in the ancestral black bear population for at least 300,000 years. Our findings, from calculating the ratio of non-synonymous to synonymous substitutions, indicate that balancing selection has maintained genetic variation of peptide-binding residues at the DQB locus of the Japanese black bear. From examination of genotype frequencies among local populations, we observed a considerably lower level of observed heterozygosity than expected. Conclusions The low level of observed heterozygosity suggests that genetic drift reduced DQB diversity in the Japanese black bear due to a bottleneck event at the population or species level. The decline of DQB diversity might have been accelerated by the loss of rare variants that have been maintained by negative frequency-dependent selection. Nevertheless, DQB diversity of the black bear appears to be relatively high compared with some other

  1. Patterns of evolution of MHC class II genes of crows (Corvus suggest trans-species polymorphism

    Directory of Open Access Journals (Sweden)

    John A. Eimes

    2015-03-01

    Full Text Available A distinguishing characteristic of genes that code for the major histocompatibility complex (MHC is that alleles often share more similarity between, rather than within species. There are two likely mechanisms that can explain this pattern: convergent evolution and trans-species polymorphism (TSP, in which ancient allelic lineages are maintained by balancing selection and retained by descendant species. Distinguishing between these two mechanisms has major implications in how we view adaptation of immune genes. In this study we analyzed exon 2 of the MHC class IIB in three passerine bird species in the genus Corvus: jungle crows (Corvus macrorhynchos japonensis American crows (C. brachyrhynchos and carrion crows (C. corone orientalis. Carrion crows and American crows are recently diverged, but allopatric, sister species, whereas carrion crows and jungle crows are more distantly related but sympatric species, and possibly share pathogens linked to MHC IIB polymorphisms. These patterns of evolutionary divergence and current geographic ranges enabled us to test for trans-species polymorphism and convergent evolution of the MHC IIB in crows. Phylogenetic reconstructions of MHC IIB sequences revealed several well supported interspecific clusters containing all three species, and there was no biased clustering of variants among the sympatric carrion crows and jungle crows. The topologies of phylogenetic trees constructed from putatively selected sites were remarkably different than those constructed from putatively neutral sites. In addition, trees constructed using non-synonymous substitutions from a continuous fragment of exon 2 had more, and generally more inclusive, supported interspecific MHC IIB variant clusters than those constructed from the same fragment using synonymous substitutions. These phylogenetic patterns suggest that recombination, especially gene conversion, has partially erased the signal of allelic ancestry in these species. While

  2. Deep convolutional neural networks for pan-specific peptide-MHC class I binding prediction.

    Science.gov (United States)

    Han, Youngmahn; Kim, Dongsup

    2017-12-28

    Computational scanning of peptide candidates that bind to a specific major histocompatibility complex (MHC) can speed up the peptide-based vaccine development process and therefore various methods are being actively developed. Recently, machine-learning-based methods have generated successful results by training large amounts of experimental data. However, many machine learning-based methods are generally less sensitive in recognizing locally-clustered interactions, which can synergistically stabilize peptide binding. Deep convolutional neural network (DCNN) is a deep learning method inspired by visual recognition process of animal brain and it is known to be able to capture meaningful local patterns from 2D images. Once the peptide-MHC interactions can be encoded into image-like array(ILA) data, DCNN can be employed to build a predictive model for peptide-MHC binding prediction. In this study, we demonstrated that DCNN is able to not only reliably predict peptide-MHC binding, but also sensitively detect locally-clustered interactions. Nonapeptide-HLA-A and -B binding data were encoded into ILA data. A DCNN, as a pan-specific prediction model, was trained on the ILA data. The DCNN showed higher performance than other prediction tools for the latest benchmark datasets, which consist of 43 datasets for 15 HLA-A alleles and 25 datasets for 10 HLA-B alleles. In particular, the DCNN outperformed other tools for alleles belonging to the HLA-A3 supertype. The F1 scores of the DCNN were 0.86, 0.94, and 0.67 for HLA-A*31:01, HLA-A*03:01, and HLA-A*68:01 alleles, respectively, which were significantly higher than those of other tools. We found that the DCNN was able to recognize locally-clustered interactions that could synergistically stabilize peptide binding. We developed ConvMHC, a web server to provide user-friendly web interfaces for peptide-MHC class I binding predictions using the DCNN. ConvMHC web server can be accessible via http://jumong.kaist.ac.kr:8080/convmhc

  3. The influence of drinking-water pollution with heavy metal on the expression of IL-4 and IFN-γ in mice by real-time polymerase chain reaction.

    Science.gov (United States)

    Radbin, Rayhaneh; Vahedi, Fatemeh; Chamani, JamshidKhan

    2014-10-01

    In recent years, water pollution has been converted to a challenging discussion in health area of human being. Heavy elements are one of the most important water pollutants and their negative adverse effects on body systems have been confirmed. In this study, investigation of effects of two heavy elements including lead (Pb) and copper (Cu) on expression of interlukin-4 (IL-4) and interferon-gamma (IFN-γ) as humoral and cellular immunity biomarkers, respectively, was aimed and PCR, real-time PCR and electrophoresis techniques were used. In this study, BALB/c mice were studied that had free access to drinking water which contained Cu or Pb salts. After 2 weeks, spleens of mice were removed, RNA extracted, and cDNA was prepared for RT-PCR. Then the expression of IL-4 and IFN-γ genes were assessed by real-time PCR. The expression of IFN-γ was up-regulated in both treated groups and the expression of IL-4 was only up-regulated in the group treated with Cu and down-regulated in the group treated with Pb. This study shows that the presence of heavy elements as drinking-water pollutants results in a disproportion of natural cytokines balances, and thus may result in a negative effect on immune system.

  4. Heavy weights

    International Nuclear Information System (INIS)

    2001-01-01

    The paper mentions the important thing that it was for the country, exporting the first shipping of crude de Castilla to a company of asphalts in United States. It was not a common sale, as those that it carries out the company with the crude of Cusiana or Cano Limon. The new of this shipping is that it was the first successful test of marketing the Colombian heavy crude in the exterior, since previously it was almost considered a curse to find heavy crude by the difficulties of its transport. Today it can be taken to any refinery of the world and the best test is that, after almost a year of efforts to overcome the barriers of the transport, the company achieved its conduction from the Castilla Field, in proximities to Villavicencio, until the Covenas Port, in the Caribbean Colombian coast

  5. Heavy ions

    CERN Multimedia

    CERN. Geneva; Antinori, Federico

    2001-01-01

    Colliding two heavy nuclei at ultrarelativistic energies allows to create in the laboratory a bulk system with huge density, pressure and temperature and to study its properties. It is estimated that in Pb-Pb collisions at CERN-SPS we reach over an appreciable volume an energy density which exceeds by more than a factor 20 that of normal nuclear matter. At such densities, the hadrons are so closely packed that they interpenetrate; novel physics phenomena are expected to appear. QCD predicts that under such conditions a phase transition from a system composed of colourless hadrons to a Quark-Gluon Plasma (QGP) should occur. A rich ultrarelativistic heavy-ion physics programme is under way both at BNL-AGS and at CERN-SPS since 1986. The results obtained so far have led CERN to officially announce evidence for a new state of matter last year. A long-range programme of heavy-ion physics at higher energies is under way (BNL-RHIC) and in preparation (CERN-LHC). These lectures are meant as an introduction to the phy...

  6. Heavy ions

    CERN Multimedia

    CERN. Geneva. Audiovisual Unit

    2002-01-01

    Colliding two heavy nuclei at ultrarelativistic energies allows to create in the laboratory a bulk system with huge density, pressure and temperature and to study its properties. It is estimated that in Pb-Pb collisions at CERN-SPS we reach over an appreciable volume an energy density which exceeds by more than a factor 20 that of normal nuclear matter. At such densities, the hadrons are so closely packed that they interpenetrate; novel physics phenomena are expected to appear. QCD predicts that under such conditions a phase transition from a system composed of colourless hadrons to a Quark-Gluon Plasma (QGP) should occur. A rich ultrarelativistic heavy-ion physics programme is under way both at BNL-AGS and at CERN-SPS since 1986. The results obtained so far have led CERN to officially announce evidence for a new state of matter last year. A long-range programme of heavy-ion physics at higher energies is under way (BNL-RHIC) and in preparation (CERN-LHC). These lectures are meant as an introduction to the phy...

  7. The N-Terminal Flanking Region of the Invariant Chain Peptide Augments the Immunogenicity of a Cryptic “Self” Epitope from a Tumor-Associated Antigen

    NARCIS (Netherlands)

    Hess, A.D.; Thoburn, C.; Chen, W.; Miura, Y.; Wall, E. van der

    2001-01-01

    The N-terminal flanking region of the invariant chain peptide termed CLIP appears to have superagonistic properties interacting with the T cell receptor and the MHC class II molecule at or near the binding site for the bacterial superantigen Staphylococcal enterotoxin B (SEB). The present studies

  8. TLR4-HMGB1 signaling pathway affects the inflammatory reaction of autoimmune myositis by regulating MHC-I.

    Science.gov (United States)

    Wan, Zemin; Zhang, Xiujuan; Peng, Anping; He, Min; Lei, Zhenhua; Wang, Yunxiu

    2016-12-01

    To analyze the effects of TLR4 on the expression of the HMGB1, MHC-I and downstream cytokines IL-6 and TNF-α, and to investigate the biological role of the TLR4-HMGB1 signaling pathway in the development of the autoimmune myositis. We built mice models with experimental autoimmune myositis (EAM) and used the inverted screen experiment to measure their muscle endurance; we also examined inflammatory infiltration of muscle tissues after HE staining; and we assessed the expression of MHC-I using immunohistochemistry. In addition, peripheral blood mononuclear cells (PBMC) were extracted and flow cytometry was utilized to detect the effect of IFN-γ on the expression of MHC-I. Furthermore, PBMCs were treated with IFN-γ, anti-TLR4, anti-HMGB1 and anti-MHC-I. Real-time PCR and western blotting were employed to examine the expressions of TLR4, HMGB1 and MHC-I in different groups. The ELISA method was also utilized to detect the expression of the downstream cytokines TNF-α and IL-6. The expressions of TLR4, HMGB1 and MHC-I in muscle tissues from mice with EAM were significantly higher than those in the control group (all Pmyositis inflammation by regulating the expression of MHC-I and other pro-inflammatory cytokines. Copyright © 2016 Elsevier B.V. All rights reserved.

  9. Detection of new MHC mutations in mice by skin grafting, tumor transplantation and monoclonal antibodies: a comparison

    International Nuclear Information System (INIS)

    Egorov, I.K.; Egorov, O.S.

    1988-01-01

    Two mechanisms of major histocompatibility complex (MHC) mutations have been described in mice: gene conversion and homologous but unequal recombination. However, the knowledge of mutations in MHC is incomplete because studies have been limited almost exclusively to two haplotypes, H-2/sup b/ and H-2/sup d/, while hundreds of haplotypes exist in nature; it has been biased by the use of only one procedure of screening for mutation, skin grafting. The authors used three procedures to screen for MHC mutations: (1) conventional techniques of skin grafting, (2) syngeneic tumor transplantation and (3) typing with monoclonal anti-MHC antibodies (mAbs) and complement. The faster technique of tumor transplantation detected mutants similar to those discovered by skin grafting technique. Screening with mAbs allowed us to detect both mutants that are capable of rejecting standard skin grafts and those that are silent in skin grafting tests, and which therefore resulted in a higher apparent mutation frequency. Two mutants of the H-2/sup a/ haplotype were found that carry concomitant class I and class II antigenic alterations. Both MHC mutants silent in skin grafting tests and mutants carrying concomitant class I and class II alterations have never been studied before and are expected to reveal new mechanisms of generating MHC mutations. 1-Ethyl-1-nitrosourea (ENU) failed to induce de novo MHC mutations in our skin grafting series

  10. HUBUNGAN ANTARA PERTUMBUHAN DENGAN KEBERADAAN GEN TAHAN PENYAKIT MAJOR HISTOCOMPATIBILITY COMPLEX (MHC PADA IKAN MAS (Cyprinus carpio

    Directory of Open Access Journals (Sweden)

    Erma Primanita Hayuningtyas

    2016-04-01

    Full Text Available Wabah penyakit koi herpes virus (KHV di Indonesia yang terjadi sejak tahun 2002 merupakan salah satu faktor yang memicu kemerosotan produksi ikan mas budidaya. Pembentukan strain unggul ikan mas tahan KHV dapat menjadi solusi bagi permasalahan tersebut. Pemilihan genotip ikan mas tahan KHV dengan marka molekuler gen major histocompatibility complex class II (MHC-II, khususnya pada alel Cyca DAB 1*05 akan membantu dalam kegiatan seleksi. Penelitian ini bertujuan untuk mengetahui keberadaan gen MHC-II pada populasi dasar G0 ikan mas strain Rajadanu dan hubungannya dengan pertumbuhan (bobot. Metode deteksi keberadaan gen MHC-II pada dua kelompok ikan dengan ukuran berbeda dilakukan dengan teknik PCR. Hubungan antara pertumbuhan ikan mas dengan persentase kemunculan gen MHC-II dianalisis dengan menggunakan program SPSS (Statistical Package for the Social Sciences, sehingga diperoleh korelasi di antara keduanya. Hasil penelitian menunjukkan bahwa hubungan antara pertumbuhan dengan persentase keberadaan gen MHC-II berkorelasi negatif dengan nilai R = -0,742. Hal ini mengindikasikan bahwa semakin cepat pertumbuhan populasi ikan mas maka semakin sedikit persentase individu yang mempunyai gen MHC-II pada setiap populasi ikan mas. Sehingga populasi ikan mas yang pertumbuhannya lambat memiliki tingkat persentase positif MHC-II lebih tinggi (85,71%-100% dibandingkan populasi ikan mas yang pertumbuhannya cepat (42,86%-85,71%.

  11. Selection, diversity and evolutionary patterns of the MHC class II DAB in free-ranging Neotropical marsupials

    Directory of Open Access Journals (Sweden)

    Otten Celine

    2008-06-01

    Full Text Available Abstract Background Research on the genetic architecture and diversity of the MHC has focused mainly on eutherian mammals, birds and fish. So far, studies on model marsupials used in laboratory investigations indicated very little or even no variation in MHC class II genes. However, natural levels of diversity and selection are unknown in marsupials as studies on wild populations are virtually absent. We used two endemic South American mouse opossums, Gracilinanus microtarsus and Marmosops incanus, to investigate characteristic features of MHC selection. This study is the first investigation of MHC selection in free-ranging Neotropical marsupials. In addition, the evolutionary history of MHC lineages within the group of marsupials was examined. Results G. microtarsus showed extensive levels of MHC diversity within and among individuals as 47 MHC-DAB alleles and high levels of sequence divergence were detected at a minimum of four loci. Positively selected codon sites were identified, of which most were congruent with human antigen binding sites. The diversity in M. incanus was rather low with only eight observed alleles at presumably two loci. However, these alleles also revealed high sequence divergence. Again, positive selection was identified on specific codon sites, all congruent with human ABS and with positively selected sites observed in G. microtarsus. In a phylogenetic comparison alleles of M. incanus interspersed widely within alleles of G. microtarsus with four alleles being present in both species. Conclusion Our investigations revealed extensive MHC class II polymorphism in a natural marsupial population, contrary to previous assumptions. Furthermore, our study confirms for the first time in marsupials the presence of three characteristic features common at MHC loci of eutherian mammals, birds and fish: large allelic sequence divergence, positive selection on specific sites and trans-specific polymorphism.

  12. Heavy metals anthropogenic pollutants in Austria

    International Nuclear Information System (INIS)

    Anderl, M.; Gager, M.; Gugele, B.; Huttunen, K.; Kurzweil, A.; Poupa, S.; Ritter, M.; Wappel, D.; Wieser, M.

    2004-01-01

    Several heavy metals from anthropogenic sources are emitted in the atmosphere damaging the air quality and the human health, besides they accumulate on the soil and lately are transmitted into the human food chain. Therefore at international level there is a concern to reduce them. Austrian heavy metals emissions (cadmium, mercury and lead) during 1990-2002 are given including an analysis of causes and sources. Lead is the main pollutant and the main sector responsible is the industry. 5 figs. (nevyjel)

  13. Specific blockade by CD54 and MHC II of CD40-mediated signaling for B cell proliferation and survival

    DEFF Research Database (Denmark)

    Doyle, I S; Hollmann, C A; Crispe, I N

    2001-01-01

    Regulation of B lymphocyte proliferation is critical to maintenance of self-tolerance, and intercellular interactions are likely to signal such regulation. Here, we show that coligation of either the adhesion molecule ICAM-1/CD54 or MHC II with CD40 inhibited cell cycle progression and promoted...... these effects. Addition of BCR or IL-4 signals did not overcome the effect of ICAM-1 or MHC II on CD40-induced proliferation. FasL expression was not detected in B cell populations. These results show that MHC II and ICAM-1 specifically modulate CD40-mediated signaling, so inhibiting proliferation...

  14. Heavy quark effective theory and heavy baryon transitions

    International Nuclear Information System (INIS)

    Hussain, F.

    1992-01-01

    The heavy quark effective theory (HQET) is applied to study the weak decay of heavy mesons and heavy baryons and to predict the form factors for heavy to heavy and heavy to light transitions. 28 refs, 10 figs, 2 tabs

  15. Molecular immune recognition of botulinum neurotoxin B. The light chain regions that bind human blocking antibodies from toxin-treated cervical dystonia patients. Antigenic structure of the entire BoNT/B molecule.

    Science.gov (United States)

    Atassi, M Zouhair; Jankovic, Joseph; Steward, Lance E; Aoki, K Roger; Dolimbek, Behzod Z

    2012-01-01

    We recently mapped the regions on the heavy (H) chain of botulinum neurotoxin, type B (BoNT/B) recognized by blocking antibodies (Abs) from cervical dystonia (CD) patients who develop immunoresistance during toxin treatment. Since blocking could also be effected by Abs directed against regions on the light (L) chain, we have mapped here the L chain, using the same 30 CD antisera. We synthesized, purified and characterized 32 19-residue L chain peptides that overlapped successively by 5 residues (peptide L32 overlapped with peptide N1 of the H chain by 12 residues). In a given patient, Abs against the L chain seemed less intense than those against H chain. Most sera recognized a limited set of L chain peptides. The levels of Abs against a given region varied with the patient, consistent with immune responses to each epitope being under separate MHC control. The peptides most frequently recognized were: L13, by 30 of 30 antisera (100%); L22, by 23 of 30 (76.67%); L19, by 15 of 30 (50.00%); L26, by 11 of 30 (36.70%); and L14, by 12 of 30 (40.00%). The activity of L14 probably derives from its overlap with L13. The levels of Ab binding decreased in the following order: L13 (residues 169-187), L22 (295-313), L19 (253-271), and L26 (351-369). Peptides L12 (155-173), L18 (239-257), L15 (197-215), L1 (1-19) and L23 (309-327) exhibited very low Ab binding. The remaining peptides had little or no Ab-binding activity. The antigenic regions are analyzed in terms of their three-dimensional locations and the enzyme active site. With the previous localization of the antigenic regions on the BoNT/B H chain, the human Ab recognition of the entire BoNT/B molecule is presented and compared to the recognition of BoNT/A by human blocking Abs. Copyright © 2011. Published by Elsevier GmbH.

  16. Determination of some heavy metals concentration in the tissues of ...

    African Journals Online (AJOL)

    Jen

    Department of Pure and Industrial Chemistry, Bayero University, Kano, P.M.B. 3011, Kano, Nigeria ... contamination (e.g. lead pipes), high ambient air concentrations near emission ... Thus heavy metals acquired through the food chain as a.

  17. Poisoning of domestic animals with heavy metals

    Directory of Open Access Journals (Sweden)

    Velev Romel

    2009-01-01

    Full Text Available The term heavy metal refers to a metal that has a relatively high density and is toxic for animal and human organism at low concentrations. Heavy metals are natural components of the Earth's crust. They cannot be degraded or destroyed. To a small extent they enter animal organism via food, drinking water and air. Some heavy metals (e.g cooper, iron, chromium, zinc are essential in very low concentrations for the survival of all forms of life. These are described as essential trace elements. However, when they are present in greater quantities, like the heavy metals lead, cadmium and mercury which are already toxic in very low concentrations, they can cause metabolic anomalies or poisoning. Heavy metal poisoning of domestic animals could result, for instance, from drinking-water contamination, high ambient air concentrations near emission sources, or intake via the food chain. Heavy metals are dangerous because they tend to bioaccumulate in a biological organism over time. Manifestation of toxicity of individual heavy metals varies considerably, depending on dose and time of exposure, species, gender and environmental and nutritional factors. Large differences exist between the effects of a single exposure to a high concentration, and chronic exposures to lower doses. The aim of this work is to present the source of poisoning and toxicity of some heavy metals (lead, mercury, cadmium, thallium, arsenic, as well as new data about effects of those heavy metals on the health of domestic animals. .

  18. Prediction of MHC class II binding affinity using SMM-align, a novel stabilization matrix alignment method

    DEFF Research Database (Denmark)

    Nielsen, Morten; Lundegaard, Claus; Lund, Ole

    2007-01-01

    the correct alignment of a peptide in the binding groove a crucial part of identifying the core of an MHC class II binding motif. Here, we present a novel stabilization matrix alignment method, SMM-align, that allows for direct prediction of peptide:MHC binding affinities. The predictive performance...... of the method is validated on a large MHC class II benchmark data set covering 14 HLA-DR (human MHC) and three mouse H2-IA alleles. RESULTS: The predictive performance of the SMM-align method was demonstrated to be superior to that of the Gibbs sampler, TEPITOPE, SVRMHC, and MHCpred methods. Cross validation...... between peptide data set obtained from different sources demonstrated that direct incorporation of peptide length potentially results in over-fitting of the binding prediction method. Focusing on amino terminal peptide flanking residues (PFR), we demonstrate a consistent gain in predictive performance...

  19. Reversible epigenetic down-regulation of MHC molecules by devil facial tumour disease illustrates immune escape by a contagious cancer

    DEFF Research Database (Denmark)

    Siddle, Hannah V; Kreiss, Alexandre; Tovar, Cesar

    2013-01-01

    Contagious cancers that pass between individuals as an infectious cell line are highly unusual pathogens. Devil facial tumor disease (DFTD) is one such contagious cancer that emerged 16 y ago and is driving the Tasmanian devil to extinction. As both a pathogen and an allograft, DFTD cells should...... be rejected by the host-immune response, yet DFTD causes 100% mortality among infected devils with no apparent rejection of tumor cells. Why DFTD cells are not rejected has been a question of considerable confusion. Here, we show that DFTD cells do not express cell surface MHC molecules in vitro or in vivo......, MHC class I molecules can be restored to the surface of DFTD cells in vitro by using recombinant devil IFN-γ, which is associated with up-regulation of the MHC class II transactivator, a key transcription factor with deacetylase activity. Further, expression of MHC class I molecules by DFTD cells can...

  20. Probing natural killer cell education by Ly49 receptor expression analysis and computational modelling in single MHC class I mice.

    Directory of Open Access Journals (Sweden)

    Sofia Johansson

    Full Text Available Murine natural killer (NK cells express inhibitory Ly49 receptors for MHC class I molecules, which allows for "missing self" recognition of cells that downregulate MHC class I expression. During murine NK cell development, host MHC class I molecules impose an "educating impact" on the NK cell pool. As a result, mice with different MHC class I expression display different frequency distributions of Ly49 receptor combinations on NK cells. Two models have been put forward to explain this impact. The two-step selection model proposes a stochastic Ly49 receptor expression followed by selection for NK cells expressing appropriate receptor combinations. The sequential model, on the other hand, proposes that each NK cell sequentially expresses Ly49 receptors until an interaction of sufficient magnitude with self-class I MHC is reached for the NK cell to mature. With the aim to clarify which one of these models is most likely to reflect the actual biological process, we simulated the two educational schemes by mathematical modelling, and fitted the results to Ly49 expression patterns, which were analyzed in mice expressing single MHC class I molecules. Our results favour the two-step selection model over the sequential model. Furthermore, the MHC class I environment favoured maturation of NK cells expressing one or a few self receptors, suggesting a possible step of positive selection in NK cell education. Based on the predicted Ly49 binding preferences revealed by the model, we also propose, that Ly49 receptors are more promiscuous than previously thought in their interactions with MHC class I molecules, which was supported by functional studies of NK cell subsets expressing individual Ly49 receptors.