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Sample records for activation antigen cd23

  1. Epstein-Barr virus nuclear antigen 2 specifically induces expression of the B-cell activation antigen CD23

    Epstein-Barr virus (EBV) infection of EBV-negative Burkitt lymphoma (BL) cells includes some changes similar to those seen in normal B lymphocytes that have been growth transformed by EBV. The role of individual EBV genes in this process was evaluated by introducing each of the viral genes that are normally expressed in EBV growth-transformed and latently infected lymphoblasts into an EBV-negative BL cell line, using recombinant retrovirus-mediated transfer. Clones of cells were derived that stably express the EBV nuclear antigen 1 (EBNA-1), EBNA-2, EBNA-3, EBNA-leader protein, or EBV latent membrane protein (LMP). These were compared with control clones infected with the retrovirus vector. All 10 clones converted to EBNA-2 expression differed from control clones or clones expressing other EBV proteins by growth in tight clumps and by markedly increased expression of one particular surface marker of B-cell activation, CD23. Other activation antigens were unaffected by EBNA-2 expression, as were markers already expressed on the parent BL cell line. The results indicate that EBNA-2 is a specific direct or indirect trans-activator of CD23. This establishes a link between an EBV gene and cell gene expression. Since CD23 has been implicated in the transduction of B-cell growth signals, its specific induction by EBNA-2 could be important in EBV induction of B-lymphocyte transformation

  2. Mast cells modulate transport of CD23/IgE/antigen complex across human intestinal epithelial barrier

    Ping-Chang Yang

    2009-06-01

    Full Text Available Background: Food allergy and chronic intestinal inflammation are common in western countries. The complex of antigen/IgE is taken up into the body from the gut lumen with the aid of epithelial cell-derived CD23 (low affinity IgE receptor II that plays an important role in the pathogenesis of intestinal allergy. This study aimed to elucidate the role of mast cell on modulation of antigen/IgE complex transport across intestinal epithelial barrier. Methods: Human intestinal epithelial cell line HT29 cell monolayer was used as a study platform. Transepithelial electric resistance (TER and permeability to ovalbumin (OVA were used as the markers of intestinal epithelial barrier function that were recorded in response to the stimulation of mast cell-derived chemical mediators. Results: Conditioned media from naïve mast cell line HMC-1 cells or monocyte cell line THP-1 cells significantly upregulated the expression of CD23 and increased the antigen transport across the epithelium. Treatment with stem cell factor (SCF, nerve growth factor (NGF, retinoic acid (RA or dimethyl sulphoxide (DMSO enhanced CD23 expression in HT29 cells. Conditioned media from SCF, NGF or RA-treated HMC-1 cells, and SCF, NGF, DMSO or RA-treated THP-1 cells enhanced immune complex transport via enhancing the expression of the CD23 in HT29 cells and the release of inflammatory mediator TNF-α. Nuclear factor kappa B inhibitor, tryptase and TNF-α inhibited the increase in CD23 in HT29 cells and prevents the enhancement of epithelial barrier permeability. Conclusions: Mast cells play an important role in modulating the intestinal CD23 expression and the transport of antigen/IgE/CD23 complex across epithelial barrier.

  3. Biochemical basis of synergy between antigen and T-helper (Th) cell-mediated activation of resting human B cells.

    Chartash, E K; Crow, M K; Friedman, S M

    1989-01-01

    We have utilized CD23 expression as a marker for B cell activation in order to investigate the biochemical basis for synergy between antigen and T helper (Th) cells in the activation of resting human B cells. Our results confirm that while ligation of surface immunoglobulin (sIg) receptors by antigen analogues (e.g., F(ab')2 goat anti-human IgM) does not lead to CD23 expression, this stimulus markedly enhances CD23 expression induced during antigen specific Th-B cell interaction or by rIL-4. ...

  4. Serum levels of total IgE and soluble CD23 in bronchial asthma

    G. Di Lorenzo

    1996-01-01

    Full Text Available The aim of the present study was to compare, during the pollen season, serum levels of total IgE and soluble CD23 (sCD23 from patients with allergic bronchial asthma, with those from healthy subjects. Significantly higher levels of total IgE and sCD23 were found in patients with asthma compared to the control group. Both in normal controls and in asthmatic patients, a significant correlation was shown between the levels of these two molecules. In asthmatic patients, significant correlations were found for both total IgE and sCD23, with lung function measured as bronchial responsiveness to inhaled methacholine. These results suggest that in asthmatic patients, in addition to the study of total serum IgE levels, the assessment of sCD23 serum levels may be helpful in the evaluation of disease activity.

  5. IgE mediates killing of intracellular Toxoplasma gondii by human macrophages through CD23-dependent, interleukin-10 sensitive pathway.

    Ioannis Vouldoukis

    Full Text Available BACKGROUND: In addition to helminthic infections, elevated serum IgE levels were observed in many protozoal infections, while their contribution during immune response to these pathogens remained unclear. As IgE/antigen immune complexes (IgE-IC bind to human cells through FcεRI or FcεRII/CD23 surface molecules, the present study aimed to identify which functional receptor may be involved in IgE-IC interaction with human macrophages, the major effector cell during parasite infection. METHODOLOGY/PRINCIPAL FINDINGS: Human monocyte-derived macrophages were infected with Toxoplasma gondii before being incubated with IgE-IC. IgE receptors were then identified using appropriate blocking antibodies. The activation of cells and parasiticidal activity were evaluated by mediator quantification and direct counting of infected macrophages. RNAs were extracted and cell supernatants were also collected for their content in tumor necrosis factor (TNF-α, interleukin-10 (IL-10 and nitrites. Sera from symptomatic infected patients were also tested for their content of IgE, IL-10 and nitrites, and compared to values found in healthy donors. Results showed that IgE-IC induced intracellular elimination of parasites by human macrophages. IgE-mediated effect was FcεRI-independent, but required cross-linking of surface FcεRII/CD23, cell activation and the generation of nitric oxide (NO. Although TNF-α was shown to be produced during cell activation, this cytokine had minor contribution in this phenomenon while endogenous and exogenous IL-10 down-regulated parasite killing. Inverse relationship was found between IL-10 and NO expression by infected human macrophages at both mRNA and mediator levels. The relationship between these in vitro data and in vivo levels of various factors in T. gondii infected patients supports the involvement of CD23 antigen and IL-10 expression in disease control. CONCLUSION: Thus, IgE may be considered as immune mediator during

  6. Structural Changes in the Lectin Domain of CD23, the Low-Affinity IgE Receptor, upon Calcium Binding

    Wurzburg, Beth A.; Tarchevskaya, Svetlana S.; Jardetzky, Theodore S. (NWU)

    2010-03-08

    CD23, the low-affinity receptor for IgE (Fc{var_epsilon}RII), regulates IgE synthesis and also mediates IgE-dependent antigen transport and processing. CD23 is a unique Fc receptor belonging to the C-type lectin-like domain superfamily and binds IgE in an unusual, non-lectin-like manner, requiring calcium but not carbohydrate. We have solved the high-resolution crystal structures of the human CD23 lectin domain in the presence and absence of Ca{sup 2+}. The crystal structures differ significantly from a previously determined NMR structure and show that calcium binding occurs at the principal binding site, but not at an auxiliary site that appears to be absent in human CD23. Conformational differences between the apo and Ca{sup 2+} bound structures suggest how IgE-Fc binding can be both calcium-dependent and carbohydrate-independent.

  7. Radioprotective activity of shigella antigens

    The possibility of using experimental microbe antigenous preparation out of Flexner and Zonne shigellas as a protector and a remedy in the case of gamma irradiation, is investigated. The experiments are carried out on mice of both sexes immunized before or after irradiation by two methods: subcutaneously and enerally. It is found that in most cases investigated, the introduction of the experimental preparation 3, 5, 7 and 10 days before irradiation increases the survivability of animals

  8. Antigen

    An antigen is any substance that causes your immune system to produce antibodies against it. This means your immune ... and is trying to fight it off. An antigen may be a substance from the environment, such ...

  9. Carbohydrate-functionalized nanovaccines preserve HIV-1 antigen stability and activate antigen presenting cells.

    Vela Ramirez, J E; Roychoudhury, R; Habte, H H; Cho, M W; Pohl, N L B; Narasimhan, B

    2014-01-01

    The functionalization of polymeric nanoparticles with ligands that target specific receptors on immune cells offers the opportunity to tailor adjuvant properties by conferring pathogen mimicking attributes to the particles. Polyanhydride nanoparticles are promising vaccine adjuvants with desirable characteristics such as immunomodulation, sustained antigen release, activation of antigen presenting cells (APCs), and stabilization of protein antigens. These capabilities can be exploited to design nanovaccines against viral pathogens, such as HIV-1, due to the important role of dendritic cells (DCs) and macrophages in viral spread. In this work, an optimized process was developed for carbohydrate functionalization of HIV-1 antigen-loaded polyanhydride nanoparticles. The carbohydrate-functionalized nanoparticles preserved antigenic properties upon release and also enabled sustained antigen release kinetics. Particle internalization was observed to be chemistry-dependent with positively charged nanoparticles being taken up more efficiently by DCs. Up-regulation of the activation makers CD40 and CD206 was demonstrated with carboxymethyl-α-d-mannopyranosyl-(1,2)-d-mannopyranoside functionalized nanoparticles. The secretion of the cytokines IL-6 and TNF-α was shown to be chemistry-dependent upon stimulation with carbohydrate-functionalized nanoparticles. These results offer important new insights upon the interactions between carbohydrate-functionalized nanoparticles and APCs and provide foundational information for the rational design of targeted nanovaccines against HIV-1. PMID:25068589

  10. Circulating levels of the innate and humoral immune regulators CD14 and CD23 are associated with adult glioma

    Zhou, Mi; Wiemels, Joseph L.; Bracci, Paige; Wrensch, Margaret R.; McCoy, Lucie; Rice, Terri; Sison, Jennette; Patoka, Joseph; Wiencke, John K.

    2010-01-01

    Allergy history has been consistently inversely associated with glioma risk. Two serologic markers, soluble CD23 (sCD23) and soluble CD14 (sCD14), are part of the innate and adaptive humoral immune systems and modulate allergic responses in opposite directions, with sCD23 enhancing and sCD14 blunting inflammatory responses. We measured sCD23 and sCD14 in serum from blood that was drawn at a single time point from 1079 glioma patients post diagnosis and 736 healthy controls. Glioma was strongl...

  11. Immunological Activities of Purified Preparations of Enterobacterial Common Antigen

    Gannon, Patrick J.; Jacobs, Diane M.; Marx, Arthur; Mayer, Hubert; Romanowska, Elzbieta; Neter, Erwin

    1982-01-01

    The immunological activities of three purified preparations of enterobacterial common antigen (ECA) obtained by different procedures were studied. ECA-Ma (method of A. Marx) was from Salmonella typhimurium TV149 (Ra mutant), ECA-My (method of H. Mayer) was from S. montevideo, and ECA-Ro (method of E. Romanowska) was from Shigella sonnei phase I. These preparations, on a weight basis, neutralized similar amounts of ECA antibodies, indicating that the serological activities were comparable. Nei...

  12. Circulating levels of the innate and humoral immune regulators CD14 and CD23 are associated with adult glioma.

    Zhou, Mi; Wiemels, Joseph L; Bracci, Paige M; Wrensch, Margaret R; McCoy, Lucie S; Rice, Terri; Sison, Jennette D; Patoka, Joseph S; Wiencke, John K

    2010-10-01

    Allergy history has been consistently inversely associated with glioma risk. Two serologic markers, soluble CD23 (sCD23) and soluble CD14 (sCD14), are part of the innate and adaptive humoral immune systems and modulate allergic responses in opposite directions, with sCD23 enhancing and sCD14 blunting inflammatory responses. We measured sCD23 and sCD14 in serum from blood that was drawn at a single time point from 1,079 glioma patients postdiagnosis and 736 healthy controls. Glioma was strongly associated with high sCD14 [highest versus lowest quartile odds ratio (OR), 3.94; 95% confidence interval (95% CI), 2.98-5.21] and low sCD23 (lowest versus highest quartile OR, 2.5; 95% CI, 1.89-3.23). Results were consistent across glioma histologic types and grades, but were strongest for glioblastoma. Whereas temozolomide treatment was not associated with either sCD14 or sCD23 levels among cases, those taking dexamethasone had somewhat lower sCD23 levels than those not taking dexamethasone. However, sCD23 was associated with case status regardless of dexamethasone treatment. These results augment the long-observed association between allergies and glioma and support a role for the innate and adaptive humoral functions of the immune system, in particular immunoregulatory proteins, in gliomagenesis. PMID:20719886

  13. Murine T-lymphocyte activation by mycobacterial antigens

    There has been renewed interest in the diagnosis of tuberculosis and other mycobacterial infections in the United States. Effective immunity to mycobacterial infections, as well as diagnosis by the skin test, involves T-cells rather than antibodies. Studies currently underway use the new technologies of monoclonal antibodies and recombinant DNA to define better mycobacterial antigens for T-cell activation, in the hope of identifying species specific antigens. Lymph node cells from mice sensitized to Mycobacterium intracellulare and Mycobacterium avium were assayed for activation by mycobacterial fractions, and cell lines and clones were generated. Comparing BALB/c and B10 mice indicated better responses to M. avium sonicate by B10 mice. A recombinant gene product containing a M. intracellulare peptide was assayed with lymph node cells and indicated excellent T-cell stimulation in BALB/c lymph node cells and cell lines. However, assays using B10 T-cell clones have yet to detect responders to the recombinant protein. Future studies using synthetic epitopes produced by recombinant DNA techniques and defined by monoclonal antibodies are necessary for the identification of reactive T-cell epitopes that are potentially species specific. 4 refs, 7 figs, 1 tab

  14. Activity profile of the CA125 antigen towards human red blood cells

    Mitić N.

    2010-01-01

    Full Text Available Starting from the mucin nature of the CA125 antigen and conditions associated with high serum concentrations, this study is an attempt to gain insight into its activity profile towards human erythrocytes. Carcinomaassociated and pregnancy-associated CA125 antigens were tested in agglutination/aggregation, adhesion and hemolysis assays. The results obtained indicated that CA125 antigens increased agglutination/aggregation and inhibited erythrocyte adhesion, but differed in their effective concentrations. Galectin-1 slightly modulated the effects observed. CA125 antigens had no effect on hemolysis. The activity profile of the CA125 antigen towards erythrocytes may have biomedical consequences in different microenvironments in relevant physiological and pathophysiological conditions.

  15. Multiple antigen glycopeptides (MAGs) with Tn tumour antigens and incorporated adjuvant: synthesis and immunobiological activities

    Ježek, Jan; Kelkar, Shripad; Vepřek, Pavel; Hajdůch, M.; Sejbal, J.; Trnka, T.

    Napoli : Edizioni Ziino, 2002 - (Benedetti, E.; Pedone, C.), s. 524-525 ISBN 88-900948-1-8. [Peptides 2002. European Peptide Symposium /27./. Sorrento (IT), 31.08.2002-06.09.2002] R&D Projects: GA ČR GA303/01/0690 Institutional research plan: CEZ:AV0Z4055905 Keywords : Tn antigen * multiple antigen glycopeptide * synthetic vaccine Subject RIV: CE - Biochemistry

  16. Do natural Treg become activated to antigen specific Treg in transplantation and in autoimmunity?

    Bruce Milne Hall; Tran, Giang T.; Nirupama eVerma; Karren ePlain; Catherine M. Robinson; Masaru eNomura; Hodgkinson, Suzanne J.

    2013-01-01

    Antigen specific Treg are often CD4+CD25+FoxP3+T cells, with a phenotype similar to natural Treg (nTreg). It is assumed that nTreg cannot develop into an antigen specific Treg as repeated culture with IL-2 and a specific antigen does not increase the capacity or potency of nTreg to promote immune tolerance or suppress in vitro. This has led to an assumption that antigen specific Treg mainly develop from CD4+CD25-FoxP3- T cells, by activation with antigen and TGF-beta in the absence of infla...

  17. The role of class I histocompatibility antigens in the regulation of T-cell activation.

    Dasgupta, J D; Cemach, K; Dubey, D P; Yunis, E J; Amos, D. B.

    1987-01-01

    Class I major histocompatibility antigens in humans (HLA antigens) were found to participate in the regulation of T-cell activation and proliferation induced by phytohemagglutinin. W6/32, a monomorphic antibody directed against class I HLA-A,B,C antigens, significantly inhibited the phytohemagglutinin-induced cell proliferation of peripheral blood lymphocytes. Almost complete suppression of cell activation was achieved on a subfraction of peripheral blood lymphocytes enriched in Mo1+ monocyte...

  18. Evolución de la leucemia linfática crónica: Valor predictivo del inmunofenotipo, el CD23 soluble y la morfología Evolution of chronic lymphocytic leukemia: Predictive value of immunophenotype, sCD23 and morphology

    Marcela A. Sarmiento

    2002-08-01

    -treated patients were enrolled. We analysed prospectively: morphology (typical, mixed and PL-CLL; immunophenotypic profile (Matutes score; sCD23 plasma levels; clinical stage; lymphocyte doubling time; b2microglobulin and karyotype abnormalities. Disease progression (need of treatment, progression to advanced stages, development of bulky organomegaly and death related to disease were considered as events. Md of follow-up 24 mo. Results: Stage 0: 11/36, PFS 80%; I: 10/36 PFS 90%; II: 13/36; III and IV: 2/36. SLE > II PFS 37%. p= 0.023. Lymphocyte doubling time 12mo. 24/31. PFS 28% vs. 80% p 350 UI/ml: 17/32. PFS 92% vs. 53% p=0.005. Immunophenotype: Score 5: 15/36, Score 4: 19/36, PFS 64%. Score 3: 2/36. p=0.516. Morphology: typical 17/35, mixed 17/35, PFS 81% vs. 57%, p=0.099. PL-CLL 1/35. Conclusions: sCD23 was suitable to predict PFS, specially useful for early stages without additional markers of active disease. Morphology (excluding PL-CLL and immunophenotype, two common tools, were not useful for the study purpose.

  19. Increased prevalence of late stage T cell activation antigen (VLA-1) in active juvenile chronic arthritis

    Ødum, Niels; Morling, Niels; Platz, P; Hofmann, B; Ryder, L P; Heilmann, C; Pedersen, F K; Nielsen, L P; Friis, J; Svejgaard, A

    1987-01-01

    the various HLA class II antigens was observed between the groups. Similarly, no significant differences in stimulatory capability in secondary mixed lymphocyte culture (MLC) were seen. The distribution of T helper/inducer (CD4+), T suppressor/cytotoxic (CD8+), and NK cells was similar in active JCA...

  20. Determination of antigenicity by radioimmunoassay and of trypsin inhibitory activities in heat or enzyme denatured ovomucoid

    The effects of heat treatment and enzymic digestion on the antigenic reactivity of ovomucoid were studied. This reactivity was mainly examined by a solid phase competitive radioimmunoassay. The trypsin inhibitory activity was also measured to elucidate its relationship to the antigenic reactivity. The antigenic reactivity and trypsin inhibitory activity diminished in parallel with increase of heating time. However, enzymic digestion caused a more rapid decrease in antigenic reactivity than in trypsin inhibitory activity. From these results, it is suggested that the structure of the antigenic determinants is destroyed in a similar manner to that of the trypsin inhibitory active site when ovomucoid is heated, while the former structure is destroyed more easily than the latter by enzymic digestion

  1. Immune activation by casein dietary antigens in bipolar disorder

    Severance, E.G.; Dupont, D.; Dickerson, F.B.; Stallings, C.R.; Origoni, A.E.; Krivogorsky, B.; Yang, S.; Haasnoot, W.; Yolken, R.H.

    2010-01-01

    Objectives: Inflammation and other immune processes are increasingly linked to psychiatric diseases. Antigenic triggers specific to bipolar disorder are not yet defined. We tested whether antibodies to bovine milk caseins were associated with bipolar disorder, and whether patients recognized differe

  2. Monoclonal antibodies putatively recognising activation and differentiation antigens

    Šinkora, Jiří; Řeháková, Zuzana; Haverson, K.; Šinkora, Marek; Dominquez, J.; Huang, CH. A.

    2001-01-01

    Roč. 80, - (2001), s. 143-164. ISSN 0165-2427 R&D Projects: GA ČR GA524/00/1280; GA AV ČR IPP2052002 Institutional research plan: CEZ:AV0Z5020903 Keywords : pig * cluster of differentiation antigens * haematopoisis Subject RIV: EC - Immunology Impact factor: 1.389, year: 2001

  3. Antigen-specific T cell activation independently of the MHC: chimeric antigen receptor (CAR-redirected T cells.

    Hinrich eAbken

    2013-11-01

    Full Text Available Adoptive T cell therapy has recently shown powerful in initiating a lasting anti-tumor response with spectacular therapeutic success in some cases. Specific T cell therapy, however, is limited since a number of cancer cells are not recognized by T cells due to various mechanisms including the limited availability of tumor-specific T cells and deficiencies in antigen processing or major histocompatibility complex (MHC expression of cancer cells. To make adoptive cell therapy applicable for the broad variety of cancer entities, patient's T cells are engineered ex vivo with pre-defined specificity by a recombinant chimeric antigen receptor (CAR which consists in the extracellular part of an antibody-derived domain for binding with a tumor-associated antigen and in the intracellular part of a TCR-derived signaling moiety for T cell activation. The specificity of CAR mediated T cell recognition is defined by the antibody domain, is independent of MHC presentation and can be extended to any target for which an antibody is available. We discuss the advantages and limitations of MHC-independent T cell targeting by an engineered CAR and review most significant progress recently made in early stage clinical trials to treat cancer.

  4. Antigen-activated dendritic cells ameliorate influenza A infections

    Boonnak, Kobporn; Vogel, Leatrice; Orandle, Marlene; Zimmerman, Daniel; Talor, Eyal; Subbarao, Kanta

    2013-01-01

    Influenza A viruses cause significant morbidity and mortality worldwide. There is a need for alternative or adjunct therapies, as resistance to currently used antiviral drugs is emerging rapidly. We tested ligand epitope antigen presentation system (LEAPS) technology as a new immune-based treatment for influenza virus infection in a mouse model. Influenza-J-LEAPS peptides were synthesized by conjugating the binding ligand derived from the β2-microglobulin chain of the human MHC class I molecu...

  5. Merkel cell polyomavirus large T antigen has growth-promoting and inhibitory activities.

    Cheng, Jingwei; Rozenblatt-Rosen, Orit; Paulson, Kelly G; Nghiem, Paul; DeCaprio, James A

    2013-06-01

    Merkel cell carcinoma (MCC) is a rare and aggressive form of skin cancer. In at least 80% of all MCC, Merkel cell polyomavirus (MCPyV) DNA has undergone clonal integration into the host cell genome, and most tumors express the MCPyV large and small T antigens. In all cases of MCC reported to date, the integrated MCPyV genome has undergone mutations in the large T antigen. These mutations result in expression of a truncated large T antigen that retains the Rb binding or LXCXE motif but deletes the DNA binding and helicase domains. However, the transforming functions of full-length and truncated MCPyV large T antigen are unknown. We compared the transforming activities of full-length, truncated, and alternatively spliced 57kT forms of MCPyV large T antigen. MCPyV large T antigen could bind to Rb but was unable to bind to p53. Furthermore, MCPyV-truncated large T antigen was more effective than full-length and 57kT large T antigen in promoting the growth of human and mouse fibroblasts. In contrast, expression of the MCPyV large T antigen C-terminal 100 residues could inhibit the growth of several different cell types. These data imply that the deletion of the C terminus of MCPyV large T antigen found in MCC serves not only to disrupt viral replication but also results in the loss of a distinct growth-inhibitory function intrinsic to this region. PMID:23514892

  6. Suppressive effects of antigens on the activity of specific activated lymphocytes: A test to define the specificity of activated lymphocytes

    HU Jun; PAN Sheng-jun; CAI Zhen-jie; GUAN De-lin; LIU Xiao-cheng

    2006-01-01

    Objective:With the regular mixed lymphocytes culture (MLC) to detect the allograft rejection, the reactivity of the activated lymphocytes (primed lymphocytes) of a recipient shows sometimes increase and sometimes decrease against the antigens from the donor, which is inconsistent with the clinical results. In order to establish a convenient method for testing the specificity of the activated lymphocytes in vitro, so as to know the rejection occurred or not by testing the existence of the specific activated lymphocytes against donor's HLA antigens in the recipient's peripheral blood. Methods: Anti-IL-2 neutralizing monoclonal antibody (anti-IL-2 N-mAb) and immunosuppressors were introduced in this test system in the presence of specific stimulators and activated lymphocytes. Results: When the activated lymphocytes were chosen from the one-way MLC 4 d to undergo re-stimulation by specific stimulators, the activity of activated lymphocytes in the treatment group was suppressed significantly compared with that in the control group. The result of this test method is consistent with the biopsy in the clinical diagnosis of rejection.Conclusion :It suggests that the activated lymphocytes can be inactivated by specific antigens in certain conditions. This can be a useful tool to define the specificity of the activated lymphocytes.

  7. Regulation of murine macrophage Ia-antigen expression by products of activated spleen cells

    1980-01-01

    This investigation examined the effects of mediators derived form activated spleen cells on macrophage Ia-antigen expression and function. Incubation of adherent thioglycollate-induced murine peritoneal macrophages(> 90% Ia-) with concanavalin A (Con A)- stimulated spleen cell supernate (Con A sup) resulted in a dose- dependent increase in the percentage of Ia-containing (Ia+) phagocytic cells, as detected by antiserum-and-complement-mediated cytotoxicity. The Ia-antigen expression of macroph...

  8. Inhibitory activities of microalgal extracts against Epstein-Barr Virus (EBV antigen expression in lymphoblastoid cells

    Koh Yih Yih

    2014-01-01

    Full Text Available The inhibitory activities of microalgal extracts against the expression of three EBV antigens, latent membrane protein (LMP1, Epstein-Barr nuclear antigen (EBNA1 and Z Epstein-Barr reactivation activator (ZEBRA were assessed by immunocytochemistry. The observation that the methanol extracts and their fractions from Ankistrodesmus convolutus, Synechococcus elongatus and Spirulina platensis exhibited inhibitory activity against EBV proteins in three Burkitt’s lymphoma cell lines at concentrations as low as 20 μg/ml suggests that microalgae could be a potential source of antiviral compounds against EBV.

  9. Antigen-specific monoclonal antibodies isolated from B cells expressing constitutively active STAT5.

    Ferenc A Scheeren

    Full Text Available BACKGROUND: Fully human monoclonal antibodies directed against specific pathogens have a high therapeutic potential, but are difficult to generate. METHODOLOGY/PRINCIPAL FINDINGS: Memory B cells were immortalized by expressing an inducible active mutant of the transcription factor Signal Transducer and Activator of Transcription 5 (STAT5. Active STAT5 inhibits the differentiation of B cells while increasing their replicative life span. We obtained cloned B cell lines, which produced antibodies in the presence of interleukin 21 after turning off STAT5. We used this method to obtain monoclonal antibodies against the model antigen tetanus toxin. CONCLUSIONS/SIGNIFICANCE: Here we describe a novel and relatively simple method of immortalizing antigen-specific human B cells for isolation of human monoclonal antibodies. These results show that STAT5 overexpression can be employed to isolate antigen specific antibodies from human memory B cells.

  10. How to Make a Non-Antigenic Protein (Auto) Antigenic: Molecular Complementarity Alters Antigen Processing and Activates Adaptive-Innate Immunity Synergy.

    Root-Bernstein, Robert

    2015-01-01

    Evidence is reviewed that complementary proteins and peptides form complexes with increased antigenicity and/or autoimmunogenicity. Five case studies are highlighted: 1) diphtheria toxin-antitoxin (antibody), which induces immunity to the normally non-antigenic toxin, and autoimmune neuritis; 2) tryptophan peptide of myelin basic protein and muramyl dipeptide ("adjuvant peptide"), which form a complex that induces experimental allergic encephalomyelitis; 3) an insulin and glucagon complex that is far more antigenic than either component individually; 4) various causes of experimental autoimmune myocarditis such as C protein in combination with its antibody, or coxsackie B virus in combination with the coxsackie and adenovirus receptor; 5) influenza A virus haemagglutinin with the outer membrane protein of the Haemophilus influenzae, which increases antigenicity. Several mechanisms cooperate to alter immunogenicity. Complexation alters antigen processing, protecting the components against proteolysis, altering fragmentation and presenting novel antigens to the immune system. Complementary antigens induce complementary adaptive immune responses (complementary antibodies and/or T cell receptors) that produce circulating immune complexes (CIC). CIC stimulate innate immunity. Concurrently, complementary antigens stimulate multiple Toll-like receptors that synergize to over-produce cytokines, which further stimulate adaptive immunity. Thus innate and adaptive immunity form a positive feedback loop. If components of the complex mimic a host protein, then autoimmunity may result. Enhanced antigenicity for production of improved vaccines and/or therapeutic autoimmunity (e.g., against cancer cells) might be achieved by using information from antibody or TCR recognition sites to complement an antigen; by panning for complements in randomized peptide libraries; or using antisense peptide strategies to design complements. PMID:26179268

  11. Examination of antigenic structure and some biological activities of hemagglutinin-neuraminidase (hn) and fusion (f) glycoprotein antigens of parainfluenza 3 virus, in vitro

    Milić Nenad S.; Gađanski-Omerović Gordana N.; Ašanin Ružica; Nisavić Jakov; Radojičić Marina

    2003-01-01

    The objective of our study was examination of the antigenic structure fusional and hemolytic activities of the surface glycoprotein HN and F antigens of purified parainfluenza (PI 3) viruses activated with 0.025 g/dl trypsin-versen (molecular weights of 112 kD, 81-82 kD and 30-31 kD), in vitro. The samples of activated PI3 virions with total protein concentrations of 0.55 and 0.27mg/ml and hemagglutinating titre of 256 and 128 HAU/0.1 ml, induced bovine turbinate(BT) cell fusion and hemolysis...

  12. Intravenously delivered glucocorticoid liposomes inhibit osteoclast activity and bone erosion in murine antigen-induced arthritis

    Hofkens, Wouter; Grevers, Lilyanne C.; Walgreen, Birgitte; de Vries, Teun J.; Leenen, Pieter J. M.; Everts, Vincent; Storm, Gert; van den Berg, Wim B.; van Lent, Peter L.

    2011-01-01

    The objective of this study was to determine the effect of systemic delivery of prednisolone phosphate (PLP) encapsulated within long circulating 'stealth' liposomes on bone erosion and osteoclast activity during experimental antigen-induced arthritis (AIA). Liposomal PLP strongly suppressed knee jo

  13. Enhancement of human natural cytotoxicity by Plasmodium falciparum antigen activated lymphocytes

    Theander, T G; Pedersen, B K; Bygbjerg, I C;

    1987-01-01

    Mononuclear cells (MNC) isolated from malaria immune donors and from donors never exposed to malaria were stimulated in vitro with soluble purified Plasmodium falciparum antigens (SPag) or PPD. After 7 days of culture the proliferative response and the cytotoxic activity against the natural killer...

  14. Inhibition of Ly-6A antigen expression prevents T cell activation

    1990-01-01

    Antisense oligonucleotides complementary to the 5' end of the mRNA encoding the Ly-6A protein were used to block the expression of that protein. Using this approach we could inhibit the expression of Ly-6A by 60-80% in antigen-primed lymph node (LN) T cells as well as in the D10 T cell clone. Inhibition of Ly-6 expression resulted in the inability to restimulate in vitro, antigen-primed T cells. It also blocked the activation of normal spleen cells by Con A, monoclonal antibody (mAb) to CD3, ...

  15. Tumorigenic activity of Merkel cell polyomavirus T antigens expressed in the stratified epithelium of mice

    Spurgeon, Megan E.; Cheng, Jingwei; Bronson, Roderick T.; Lambert, Paul F.; DeCaprio, James A.

    2015-01-01

    Merkel cell polyomavirus (MCPyV) is frequently associated with Merkel cell carcinoma (MCC), a highly aggressive neuroendocrine skin cancer. Most MCC tumors contain integrated copies of the viral genome with persistent expression of the MCPyV large T (LT) and small T (ST) antigen. MCPyV isolated from MCC typically contain wild type ST but truncated forms of LT that retain the N-terminus but delete the C-terminus and render LT incapable of supporting virus replication. To determine the oncogenic activity of MCC tumor-derived T antigens in vivo, a conditional, tissue-specific mouse model was developed. Keratin 14-mediated Cre recombinase expression induced expression of MCPyV T antigens in stratified squamous epithelial cells and Merkel cells of the skin epidermis. Mice expressing MCPyV T antigens developed hyperplasia, hyperkeratosis, and acanthosis of the skin with additional abnormalities in whisker pads, footpads and eyes. Nearly half of the mice also developed cutaneous papillomas. Evidence for neoplastic progression within stratified epithelia included increased cellular proliferation, unscheduled DNA synthesis, increased E2F-responsive genes levels, disrupted differentiation, and presence of a DNA damage response. These results indicate that MCPyV T antigens are tumorigenic in vivo, consistent with their suspected etiological role in human cancer. PMID:25596282

  16. Tumorigenic activity of merkel cell polyomavirus T antigens expressed in the stratified epithelium of mice.

    Spurgeon, Megan E; Cheng, Jingwei; Bronson, Roderick T; Lambert, Paul F; DeCaprio, James A

    2015-03-15

    Merkel cell polyomavirus (MCPyV) is frequently associated with Merkel cell carcinoma (MCC), a highly aggressive neuroendocrine skin cancer. Most MCC tumors contain integrated copies of the viral genome with persistent expression of the MCPyV large T (LT) and small T (ST) antigen. MCPyV isolated from MCC typically contains wild-type ST but truncated forms of LT that retain the N-terminus but delete the C-terminus and render LT incapable of supporting virus replication. To determine the oncogenic activity of MCC tumor-derived T antigens in vivo, a conditional, tissue-specific mouse model was developed. Keratin 14-mediated Cre recombinase expression induced expression of MCPyV T antigens in stratified squamous epithelial cells and Merkel cells of the skin epidermis. Mice expressing MCPyV T antigens developed hyperplasia, hyperkeratosis, and acanthosis of the skin with additional abnormalities in whisker pads, footpads, and eyes. Nearly half of the mice also developed cutaneous papillomas. Evidence for neoplastic progression within stratified epithelia included increased cellular proliferation, unscheduled DNA synthesis, increased E2F-responsive genes levels, disrupted differentiation, and presence of a DNA damage response. These results indicate that MCPyV T antigens are tumorigenic in vivo, consistent with their suspected etiologic role in human cancer. PMID:25596282

  17. Attenuated recombinant vaccinia virus expressing oncofetal antigen (tumor-associated antigen) 5T4 induces active therapy of established tumors.

    Mulryan, Kate; Ryan, Matthew G; Myers, Kevin A; Shaw, David; Wang, Who; Kingsman, Susan M; Stern, Peter L; Carroll, Miles W

    2002-10-01

    The human oncofetal antigen 5T4 (h5T4) is a transmembrane glycoprotein overexpressed by a wide spectrum of cancers, including colorectal, ovarian, and gastric, but with a limited normal tissue expression. Such properties make 5T4 an excellent putative target for cancer immunotherapy. The murine homologue of 5T4 (m5T4) has been cloned and characterized, which allows for the evaluation of immune intervention strategies in "self-antigen" in vivo tumor models. We have constructed recombinant vaccinia viruses based on the highly attenuated and modified vaccinia virus ankara (MVA strain), expressing h5T4 (MVA-h5T4), m5T4 (MVA-m5T4), and Escherichia coli LacZ (MVA-LacZ). Immunization of BALB/c and C57BL/6 mice with MVA-h5T4 and MVA-m5T4 constructs induced antibody responses to human and mouse 5T4, respectively. C57BL/6 and BALB/c mice vaccinated with MVA-h5T4 were challenged with syngeneic tumor line transfectants, B16 melanoma, and CT26 colorectal cells that express h5T4. MVA-h5T4-vaccinated mice showed significant tumor retardation compared with mice vaccinated with MVA-LacZ or PBS. In active treatment studies, inoculation with MVA-h5T4 was able to treat established CT26-h5T4 lung tumor and to a lesser extent B16.h5T4 s.c. tumors. Additionally, when C57BL/6 mice vaccinated with MVA-m5T4 were challenged with B16 cells expressing m5T4, resulting growth of the tumors was significantly retarded compared with control animals. Furthermore, mice vaccinated with MVA-m5T4 showed no signs of autoimmune toxicity. These data support the use of MVA-5T4 for tumor immunotherapy. PMID:12481437

  18. Adenoidal tissue expression of CD23 (FcεRII: An evaluation with reference to recurrent upper respiratory tract complaints and allergy in children

    Demet Alaygut

    2013-03-01

    Full Text Available Objective: In this study, CD23, low affinity immunoglobulinE receptor, expression in the adenoid tissue was investigatedimmunohistochemically and evaluated with regardto upper respiratory tract infection complaints and allergy.Methods: This retrospective study was performed by theselection of 100 patients aged 2-13 years who underwentadenoidectomy/adenotonsillectomy and in whom the adenoidtissue pathological studies were reported as “lymphoidhyperplasia and chronic infection” were evaluated.Immunohistochemical evaluation of CD23 expressionwas scored semiquantitatively between 0-3 in the tissuesamples.Results: The mean age in the study group was 70.7months; 46% were female; 30% of patients had adenoidectomyonly. Following the operation, the infection frequencydecreased in 91% of patients, whereas allergysymptoms were unchanged in 84%. CD23 expressionwas found significantly lower in patients who had allergicmanifestations, namely urticaria (p=0.041, drug sensitivity(p=0.035 and pollen allergy (p=0.037.Conclusion: A significantly reduced CD23 expressionwas found in adenoidal tissue in patients with allergicsymptoms. These results can be assessed as an underlyingmechanism for the recurrence of respiratory tractcomplaints in these children, despite adenoidectomy. JClin Exp Invest 2013; 4 (1: 1-7Key words: CD23 expression, adenoid tissue, atopy

  19. Molecular signals in antigen presentation. II. Activation of cytolytic cells in vitro after ultraviolet radiation or combined gamma and ultraviolet radiation treatment of antigen-presenting cells

    Murine low-density spleen cells have potent antigen-presenting ability in a hapten-specific cytolytic T lymphocyte (CTL) system using the hapten azobenzenearsonate (ABA). Exposure of these cells to 0.33 KJ/m2 of ultraviolet radiation (UVR) after coupling to hapten results in markedly inhibited antigen-presenting function that can be substantially corrected or bypassed by interleukin 1 (IL 1). These results have been interpreted to reflect an inhibition of Lyt-1+ T cell activation by UVR-treated APC. Treatment of these cells sequentially with 1500 rad of γ-radiation (GR) prior to hapten coupling, followed by 0.33 KJ/m2 of UVR radiation after coupling, results in an antigen-resenting defect only minimally improved by IL 1. However, partially purified interleukin 2 (IL 2) can completely bypass or correct this defect. Thus, combined Cr and UVR induces a different or more profound defect in APC function when compared to UVR alone. However, these cells do provide a signal(s) other than hapten necessary for CTL activation because ABA-coupled high density spleen cells do not activate CTL cells, even with the addition of IL 2. Fluorescence-activated cell sorter analysis demonstrates that exposure of these low density spleen cells to GP or UVR results in decreased I-A antigen expression at 24 hr; exposure to both GR and UVR results in a greater decrease in I-A antigen expression at 24 hr than either alone. The addition of nonhapten-coupled low-density APC partially reconstitutes the ability of combined GR/UVR-treated LD-APC to present antigen, and this effect is enhanced by the administration of exogenous IL 1

  20. Antigen Presentation and T-Cell Activation Are Critical for RBP4-Induced Insulin Resistance.

    Moraes-Vieira, Pedro M; Castoldi, Angela; Aryal, Pratik; Wellenstein, Kerry; Peroni, Odile D; Kahn, Barbara B

    2016-05-01

    Adipose tissue (AT) inflammation contributes to impaired insulin action, which is a major cause of type 2 diabetes. RBP4 is an adipocyte- and liver-derived protein with an important role in insulin resistance, metabolic syndrome, and AT inflammation. RBP4 elevation causes AT inflammation by activating innate immunity, which elicits an adaptive immune response. RBP4-overexpressing mice (RBP4-Ox) are insulin resistant and glucose intolerant and have increased AT macrophages and T-helper 1 cells. We show that high-fat diet-fed RBP4(-/-) mice have reduced AT inflammation and improved insulin sensitivity versus wild type. We also elucidate the mechanism for RBP4-induced macrophage antigen presentation and subsequent T-cell activation. In RBP4-Ox, AT macrophages display enhanced c-Jun N-terminal kinase, extracellular signal-related kinase, and p38 phosphorylation. Inhibition of these pathways and of NF-κB reduces activation of macrophages and CD4 T cells. MyD88 is an adaptor protein involved in proinflammatory signaling. In macrophages from MyD88(-/-) mice, RBP4 fails to stimulate secretion of tumor necrosis factor, IL-12, and IL-6 and CD4 T-cell activation. In vivo blockade of antigen presentation by treating RBP4-Ox mice with CTLA4-Ig, which blocks costimulation of T cells, is sufficient to reduce AT inflammation and improve insulin resistance. Thus, MyD88 and downstream mitogen-activated protein kinase and NF-κB pathways are necessary for RBP4-induced macrophage antigen presentation and subsequent T-cell activation. Also, blocking antigen presentation with CTLA4-Ig improves RBP4-induced insulin resistance and macrophage-induced T-cell activation. PMID:26936962

  1. Exposure to ozone enhances antigen-presenting activity concentration dependently in rats

    The effect of ozone (O3) on the symptoms of allergic asthma and the mechanisms underlying have not yet been fully elucidated. Antigen presentation is one of the factors contributing to the allergic reaction. Therefore, we investigated the effects of repeated exposure to O3 on antigen-presenting (AP) activity, on the expression of cell-surface molecules associated with antigen presentation (Ia, B7.1, B7.2 and CD11b/c) in bronchoalveolar lavage cells (BAL cells), and on allergic asthma-like symptoms. Rats were exposed to 0.3, 0.56, 1 ppm O3 or filtered air for a 3-day period every 2 weeks, this was replicated three times. AP activity was assessed by measuring antigen-specific T-cell proliferation; and the expression of cell-surface molecules, by flow cytometry. Rats were also made to inhale aerosolized 1% ovalbumin (OVA) or saline for 10 min post-exposure to O3, and allergic asthma-like symptoms were measured by determining the increase in enhanced pause (Penh), which correlates well with lung resistance. O3 increased both AP activity and expression of Ia and costimulatory molecules in BAL cells concentration dependently. It also increased lung resistance, and the increase in lung resistance after O3 exposure was significantly higher in the OVA-inhaled group than in the saline-inhaled group. The present results show that O3 increased AP activity concentration dependently and suggest that O3 might aggravate allergy symptoms by enhancing AP activity

  2. Soluble Expression and Characterization of Biologically Active Bacillus anthracis Protective Antigen in Escherichia coli

    Nagendra Suryanarayana; Vanlalhmuaka,; Bharti Mankere; Monika Verma; Kulanthaivel Thavachelvam; Urmil Tuteja

    2016-01-01

    Bacillus anthracis secretory protein protective antigen (PA) is primary candidate for subunit vaccine against anthrax. Attempts to obtain large quantity of PA from Escherichia coli expression system often result in the formation of insoluble inclusion bodies. Therefore, it is always better to produce recombinant proteins in a soluble form. In the present study, we have obtained biologically active recombinant PA in small scale E. coli shake culture system using three different expression cons...

  3. Antigen transfer from exosomes to dendritic cells as an explanation for the immune enhancement seen by IgE immune complexes.

    Rebecca K Martin

    Full Text Available IgE antigen complexes induce increased specific T cell proliferation and increased specific IgG production. Immediately after immunization, CD23(+ B cells capture IgE antigen complexes, transport them to the spleen where, via unknown mechanisms, dendritic cells capture the antigen and present it to T cells. CD23, the low affinity IgE receptor, binds IgE antigen complexes and internalizes them. In this study, we show that these complexes are processed onto B-cell derived exosomes (bexosomes in a CD23 dependent manner. The bexosomes carry CD23, IgE and MHC II and stimulate antigen specific T-cell proliferation in vitro. When IgE antigen complex stimulated bexosomes are incubated with dendritic cells, dendritic cells induce specific T-cell proliferation in vivo, similar to IgE antigen complexes. This suggests that bexosomes can provide the essential transfer mechanism for IgE antigen complexes from B cells to dendritic cells.

  4. Activation/Inhibition of mast cells by supra-optimal antigen concentrations

    Huber, Michael

    2013-01-01

    Mast cells (MCs) are tissue resident cells of hemopoietic origin and are critically involved in allergic diseases. MCs bind IgE by means of their high-affinity receptor for IgE (FcεRI). The FcεRI belongs to a family of multi-chain immune recognition receptors and is activated by cross-linking in response to multivalent antigens (Ags)/allergens. Activation of the FcεRI results in immediate release of preformed granular substances (e.g. histamine, heparin, and proteases), generation of arachido...

  5. Antibodies recognizing a variety of different structural motifs on meningococcal Lip antigen fail to demonstrate bactericidal activity.

    Tinsley, C R; Virji, M; Heckels, J E

    1992-11-01

    The neisserial Lip antigen is a conserved antigen associated with the pathogenic Neisseria species, and is composed of multiple repeats of a consensus pentapeptide. A series of monoclonal antibodies reacting with meningococcal Lip antigen were subjected to epitope mapping, using solid-phase synthetic peptides based on the consensus repeat sequence. The antibodies were found to recognize different continuous epitopes based on the consensus sequence. One monoclonal antibody was utilized in affinity chromatography to obtain purified Lip antigen and the antigen was used for immunization of mice. The resulting antisera did not recognize Lip antigen on Western blots but reacted specifically with Lip antigen in immune precipitation experiments, indicating that the predominant polyclonal immune response was directed against conformational epitopes. Despite the diversity of both continuous and conformational epitopes recognized by the antibodies produced, none of the antibodies demonstrated the ability to promote complement-mediated bactericidal activity. Thus despite its initial apparent promise as a potential vaccine candidate the case for the inclusion of Lip antigen in vaccine formulation cannot be supported at present. PMID:1282535

  6. Kinetics of T cell-activation molecules in response to Mycobacterium tuberculosis antigens

    Antas Paulo RZ

    2002-01-01

    Full Text Available The phenotypic features acquired subsequent to antigen-specific stimulation in vitro were evaluated by means of the kinetic expressions of CD69 and CD25 activation molecules on T lymphocytes and assayed by flow cytometry in response to PPD, Ag85B, and ferritin in PPD-positive healthy control individuals. In response to PHA, CD69 staining on both CD4+ and CD8+ T cells became initially marked after 4 h, peaked at 24 h, and quickly decreased after 120 h. For CD25, a latter expression was detected around 8 h, having increased after 96 h. As expected, the response rate to the mycobacterial antigens was much lower than that to the mitogen. Positive staining was high after 96 h for CD25 and after 24 h for CD69. CD69 expression was significantly enhanced (p < 0.05 on CD8+ as compared to CD4+ T cells. High levels were also found between 96-120 h. Regarding Ag85B, CD25+ cells were mostly CD4+ instead of CD8+ T cells. Moreover, in response to ferritin, a lower CD25 expression was noted. The present data will allow further characterization of the immune response to new mycobacterial-specific antigens and their evaluation for possible inclusion in developing new diagnostic techniques for tuberculosis as well in a new vaccine to prevent the disease.

  7. Evaluation of the antigenicity of hydrolyzed cow's milk protein formulas using the mouse basophil activation test.

    Iwamoto, Hiroshi; Matsubara, Takeshi; Nakazato, Yuki; Namba, Kazuyoshi; Takeda, Yasuhiro

    2016-02-01

    Hypoallergenic infant formulas are widely used for infants with cow's milk allergy. The aim of this study was to assess the utility of the mouse basophil activation test (BAT) in the evaluation of residual antigenicity in these formulas. Whole blood samples derived from β-lactoglobulin- or casein-immunized mice were incubated with one of the following formulas: conventional, partially hydrolyzed, or extensively hydrolyzed. Basophilic activation was analyzed by flow cytometry using an IgE-dependent activation marker CD200R1 and an IgG-dependent activation marker CD200R3. Systemic anaphylaxis was induced by i.v. injection of milk formula and results were compared. Conventional formula induced pronounced changes in CD200R1 and CD200R3 expression on basophils, whereas extensively hydrolyzed formulas did not elicit any changes in these markers. Similarly, challenge with conventional formula induced anaphylaxis, whereas extensively hydrolyzed formulas did not induce anaphylaxis. Although the partially hydrolyzed formula also induced basophilic activation and systemic anaphylaxis, the magnitude of these effects was smaller than that observed with the conventional formula. Compared to CD200R1, the observed trend in CD200R3 expression resembled the results obtained from systemic anaphylaxis test more closely. These findings show that mouse BAT, in particular using CD200R3, is highly useful for the evaluation of antigenicity of milk formulas. PMID:26626100

  8. Bacteroides gingivalis antigens and bone resorbing activity in root surface fractions of periodontally involved teeth

    Patters, M.R.; Landsberg, R.L.; Johansson, L.A.; Trummel, C.L.; Robertson, P.R. (Department of Periodontology, University of Connecticut, School of Dental Medicine, Farmington, Connecticut, U.S.A.)

    1982-01-01

    Bone resorbing activity and the presence of antigens of Bacteroides gingivalis were assessed in plaque, calculus, cementum, and dentin obtained from roots of teeth previously exposed to periodontitis. Each fraction was obtained by scaling the root surface. The fraction were extracted by stirring and sonication, and the soluble centrifuged, sterilized, dialyzed, and adjusted to equivalent protein concentrations. Cementum and dentin extracts from impacted teeth were prepared similarly and served as controls. Stimulation of bone resorption by each extract was assessed in organ cultures of fetal rat bones by measurement of release of previously-incorporated /sup 45/Ca from the bone into the medium. In some groups of teeth, calculus and cementum were treated with acid prior to scaling. Citric acid washes were recovered and dialyzed. An enzyme-linked immunosorbent assay (ELISA) was used to assess the extracts for the presence of antigens reactive with an antiserum to B. gingivalis. Significant stimulation of bone resorption was found in all calculus and periodontally-involved cementum preparations. ELISA showed significant levels of B.gingivalis antigens in plaque, calculus, and cementum of periodontally-involved teeth, but not in involved dentin nor in cementum or dentin of impact teeth. Treatment with citric acid removed essentially all B.gingivalis antigens from cementum but not calculus. The results suggest that substances which stimulate bone resorption and substances which react with B. gingivalis antiserum are present in surface plaque, calculus, and cementum or periodontally-involved teeth. These substances are not present in cementum and dentin of impacted teeth nor in dentin of periodontally-involved teeth. Treatment by both scaling and citric demineralization will remove most of these substances from cementum of teeth previously exposed to periodontitis.

  9. Bacteroides gingivalis antigens and bone resorbing activity in root surface fractions of periodontally involved teeth

    Bone resorbing activity and the presence of antigens of Bacteroides gingivalis were assessed in plaque, calculus, cementum, and dentin obtained from roots of teeth previously exposed to periodontitis. Each fraction was obtained by scaling the root surface. The fraction were extracted by stirring and sonication, and the soluble centrifuged, sterilized, dialyzed, and adjusted to equivalent protein concentrations. Cementum and dentin extracts from impacted teeth were prepared similarly and served as controls. Stimulation of bone resorption by each extract was assessed in organ cultures of fetal rat bones by measurement of release of previously-incorporated 45Ca from the bone into the medium. In some groups of teeth, calculus and cementum were treated with acid prior to scaling. Citric acid washes were recovered and dialyzed. An enzyme-linked immunosorbent assay (ELISA) was used to assess the extracts for the presence of antigens reactive with an antiserum to B. gingivalis. Significant stimulation of bone resorption was found in all calculus and periodontally-involved cementum preparations. ELISA showed significant levels of B.gingivalis antigens in plaque, calculus, and cementum of periodontally-involved teeth, but not in involved dentin nor in cementum or dentin of impact teeth. Treatment with citric acid removed essentially all B.gingivalis antigens from cementum but not calculus. The results suggest that substances which stimulate bone resorption and substances which react with B. gingivalis antiserum are present in surface plaque, calculus, and cementum or periodontally-involved teeth. These substances are not present in cementum and dentin of impacted teeth nor in dentin of periodontally-involved teeth. Treatment by both scaling and citric demineralization will remove most of these substances from cementum of teeth previously exposed to periodontitis. (author)

  10. An activation antigen on a subpopulation of B lymphocytes identified by the monoclonal antibody CMRF-17.

    Peach, S F; Davidson, S E; McKenzie, J L; Nimmo, J C; Hart, D N

    1989-07-01

    The identification of membrane molecules expressed on subpopulations of B lymphocytes is of potential significance because these molecules may be candidates for regulating the activation, proliferation and differentiation of B cells. A new monoclonal antibody, CMRF-17, which reacts with a subpopulation of tonsil B lymphocytes has been produced. The antibody did not react with T lymphocytes in tonsil or peripheral blood nor most peripheral blood B lymphocytes but did label erythrocytes and some platelets. In tonsil, the germinal centre cells, cells in the interfollicular region and endothelial cells were positive, but mantle zone B cells were negative. Double labelling experiments showed that CMRF-17 reacted with activated tonsillar lymphocytes. The antigen recognized by CMRF-17 was heat stable, resistant to treatment with proteolytic enzymes and neuraminidase and was shown to be a carbohydrate determinant on one or more glycolipids. These characteristics of the antigen recognized by CMRF-17 and its pattern of reactivity distinguish this antibody from other monoclonal antibodies recognizing B-cell activation markers. It was notable that of the B-lymphoid malignancies tested to date, including those of probable follicular origin, few stained with CMRF-17. PMID:2474491

  11. A Viral Vectored Prime-Boost Immunization Regime Targeting the Malaria Pfs25 Antigen Induces Transmission-Blocking Activity

    Goodman, Anna L.; Blagborough, Andrew M.; Sumi Biswas; Yimin Wu; Hill, Adrian V.; Sinden, Robert E.; Draper, Simon J

    2011-01-01

    The ookinete surface protein Pfs25 is a macrogamete-to-ookinete/ookinete stage antigen of Plasmodium falciparum, capable of exerting high-level anti-malarial transmission-blocking activity following immunization with recombinant protein-in-adjuvant formulations. Here, this antigen was expressed in recombinant chimpanzee adenovirus 63 (ChAd63), human adenovirus serotype 5 (AdHu5) and modified vaccinia virus Ankara (MVA) viral vectored vaccines. Two immunizations were administered to mice in a ...

  12. Tritium (3H) radiolabeling of protein A and antibody to high specific activity: Application to cell surface antigen radioimmunoassays

    Staphylococcal protein A and several different immunoglobulins have been radiolabeled to high specific activities (> 106 cpm/μg) by reductive methylation with tritiated (3H) sodium borohydride. The proteins retain excellent functional and antigenic properties. The utility of these reagents in a variety of assays for cell surface antigens is illustrated. The results indicate that this radiolabeling procedure may become the method of choice for many cell surface and solution immunoassays. (Auth.)

  13. Analysis of immune responses against a wide range of Mycobacterium tuberculosis antigens in patients with active pulmonary tuberculosis

    Kassa, D.; Ran, L.; Geberemeskel, W.; Tebeje, M; Alemu, A.; Selase, A.; Tegbaru, B.; Franken, K. L. M. C.; Friggen, A. H.; van Meijgaarden, K. E.; Ottenhoff, T. H. M.; Wolday, D.; Messele, T.; van Baarle, D.

    2012-01-01

    Characterizing host immune responses to molecular targets of Mycobacterium tuberculosis is essential to develop effective immunodiagnostics and better vaccines. We investigated the immune response against a large series of M. tuberculosis antigens, including 5 classical and 64 nonclassical (39 DosR regulon-encoded, 4 resuscitation-promoting factor [RPF], and 21 reactivation-associated) antigens in active-pulmonary-tuberculosis (TB) patients. Whole blood from TB patients (n = 34) was stimulate...

  14. INDUCEMENT OF ANTITUMOR-IMMUNITY BY DC ACTIVATED BY HSP70-H22 TUMOR ANTIGEN PEPTIDE

    冯作化; 黄波; 张桂梅; 李东; 王洪涛

    2003-01-01

    Objective: To investigate the feasibility of decreasing the dosage of tumor antigen peptides by dendritic cell (DC)-presenting and the characteristics of modification of DC by heat shock protein (Hsp70) and antigen peptides. Methods: Peptides were bound to Hsp70 and used to modify DC in vitro. The metabolism of the modified DC and the cytokines secreted by the modified DC were determined. The activation of lymphocytes by the modified DC and Hsp70-H22 peptides was tested. The cytotoxicity of the activated lymphocytes to H22 tumor cells was analyzed. The inhibitory effect of tumor in mice by the injection of DC and Hsp70-H22 peptides was tested. Results: 0.15μg of H22 peptides bound with Hsp70 could make 2×105 DC mature. 4×103 matured DC could activate 2×106 lymphocytes. The same amount of lymphocytes could be activated to produce similar cytotoxicity to tumor cells by either DC modified by 0.003μg of peptides bound with Hsp70 or by direct stimulation with 0.15μg of peptides bound with Hsp70. The dosage of peptides could be reduced by about 50 folds if the modified DC was used for injection instead of Hsp70-peptides. Peptides from normal hepatocytes, bound with Hsp70, could not make DC mature, nor activate lymphocytes through DC. Conclusion: The dosage of Hsp70-H22 peptides can be reduced significantly by DC-presenting to activate lymphocytes. Peptides from normal cells could not activate lymphocytes by either Hsp70-presenting or DC-presenting and they have little chance to induce autoimmunity.

  15. Surface expression of Mo3e antigen by activated human monocytes and U-937 cells

    Todd R.F. III; Bury, M.J.; Liu, D.Y.

    1986-03-05

    The surface expression of a protease-sensitive antigen, Mo3e, by activated human monocytes and U-937 cells is a plasma membrane feature of the activated state. Mo3e, which is an 80 kD protein on Western blot analysis, may represent the surface receptor for migration inhibitory factor (MIF), as evidenced by inhibition of MIF responsiveness produced by anti-Mo3e monoclonal antibody. Mo3e is barely detectable (by surface immunofluorescence) on freshly isolated monocytes but becomes expressed in high antigen density during 18-24 hrs culture in medium containing E. coli lipopolysaccharide (> 1 ng/ml), 4..beta..-phorbol 12-myristate 13-acetate (PMA) (5-10 nM), or muramyl dipeptide (0.1-1 ..mu..M). In U-937 cells, Mo3e surface expression is detectable after 24 hrs exposure to PMA and other pharmacological activators of protein kinase C: 4..beta..-phorbol 12, 13 dibutyrate, 4..beta..-phorbol 12, 13 didecanoate, mezerein, or Sn-1,2-dioctanoylglycerol. The biologically-inactivate phorbol compounds, 4..cap alpha..-phorbol 12, 13 didecanoate and 4/sub ..beta../-phorbol do not stimulate Mo3e expression. The calcium ionophore, ionomycin, has a synergistic effect on Mo3e expression stimulated by PMA; conversely, calcium antagonists block PMA-induced Mo3e expression. These results suggest the involvement of protein kinase C activation and intracellular calcium mobilization in the stimulated expression of Mo3e by activated human mononuclear phagocytes.

  16. Naive T lymphocytes traffic to inflamed central nervous system, but require antigen recognition for activation

    Krakowski, M L; Owens, T

    2000-01-01

    Organ-specific autoimmune diseases may be induced by infiltration of the target tissue by CD4(+) T cells with specificity for self antigen(s). As disease progresses, T cells of other specificities appear in the tissue. Traffic of naive, antigen-inexperienced T cells to target tissues has not been...

  17. Typing of HLA class II and class I antigens using PHA-activated, IL-2-propagated T lymphocytes.

    Leshem, B; Cohen, I; Sherman, L; Brautbar, C; Kedar, E

    1988-06-28

    We describe here a simple procedure, by which HLA class II antigens can be accurately and reliably identified in those patients where there is minimal or absent expression of HLA-DR,DQw antigens on B cells, or when the total number of leukocytes recovered from the patients do not permit reliable typing. Ficoll-Hypaque-separated peripheral blood mononuclear leukocytes, fresh or cryopreserved, were activated by PHA and then propagated in IL-2-containing medium until enough cells for typing were obtained (usually 7-14 days). At this stage, the cultured cells were shown to be primarily T cells (greater than 90% CD3+). Since the activated T cells propagate in the presence of IL-2, even a small number (10(4] of fresh or cryopreserved patients' cells suffice for this protocol. To date we have been able to successfully HLA-DR,DQw type 34/34 bone marrow transplantation candidates and 12/12 long-term dialysis patients, who were untypable using fresh cells. HLA-DR,DQw antigens on activated T cells from normal individuals were identical to those found on their uncultured B cells. In addition, class I antigens that were undetectable on the uncultured cells of one patient could be identified on activated T cells. The HLA antigens identified on the patients' activated T cells were confirmed by phenotypic analysis of cells from family members. PMID:3260612

  18. Influence of circulating antigen on blood pool activity of a radioiodinated monoclonal antibody

    Athymic mice with and without circulating CA 125 antigen were injected with 0.1-100 μg of 131I-labeled OC 125 F(ab')2 antibody fragment. Both the blood clearance of 131I activity and the change in serum CA 125 were monitored over 24 h. Influence of CA 125 on blood pool activity could be avoided only at the 100 μg dose. In patient studies, circulating CA 125 levels decreased for the first 2 h after injection of OC 125 F(ab')2 but generally returned to preinjection levels shortly thereafter. In vitro binding studies using the sera from patients injected with 131I-labeled OC 125 F(ab')2 suggest that circulating CA 125 could interfere with the tumor uptake of the labeled antibody. (author)

  19. Vitamin D controls T cell antigen receptor signaling and activation of human T cells

    von Essen, Marina Rode; Kongsbak, Martin; Schjerling, Peter;

    2010-01-01

    Phospholipase C (PLC) isozymes are key signaling proteins downstream of many extracellular stimuli. Here we show that naive human T cells had very low expression of PLC-gamma1 and that this correlated with low T cell antigen receptor (TCR) responsiveness in naive T cells. However, TCR triggering...... led to an upregulation of approximately 75-fold in PLC-gamma1 expression, which correlated with greater TCR responsiveness. Induction of PLC-gamma1 was dependent on vitamin D and expression of the vitamin D receptor (VDR). Naive T cells did not express VDR, but VDR expression was induced by TCR...... signaling via the alternative mitogen-activated protein kinase p38 pathway. Thus, initial TCR signaling via p38 leads to successive induction of VDR and PLC-gamma1, which are required for subsequent classical TCR signaling and T cell activation....

  20. A novel approach for reliable detection of cathepsin S activities in mouse antigen presenting cells.

    Steimle, Alex; Kalbacher, Hubert; Maurer, Andreas; Beifuss, Brigitte; Bender, Annika; Schäfer, Andrea; Müller, Ricarda; Autenrieth, Ingo B; Frick, Julia-Stefanie

    2016-05-01

    Cathepsin S (CTSS) is a eukaryotic protease mostly expressed in professional antigen presenting cells (APCs). Since CTSS activity regulation plays a role in the pathogenesis of various autoimmune diseases like multiple sclerosis, atherosclerosis, Sjögren's syndrome and psoriasis as well as in cancer progression, there is an ongoing interest in the reliable detection of cathepsin S activity. Various applications have been invented for specific detection of this enzyme. However, most of them have only been shown to be suitable for human samples, do not deliver quantitative results or the experimental procedure requires technical equipment that is not commonly available in a standard laboratory. We have tested a fluorogen substrate, Mca-GRWPPMGLPWE-Lys(Dnp)-DArg-NH2, that has been described to specifically detect CTSS activities in human APCs for its potential use for mouse samples. We have modified the protocol and thereby offer a cheap, easy, reproducible and quick activity assay to detect CTSS activities in mouse APCs. Since most of basic research on CTSS is performed in mice, this method closes a gap and offers a possibility for reliable and quantitative CTSS activity detection that can be performed in almost every laboratory. PMID:26899824

  1. A small molecule inhibitor for ATPase activity of Hsp70 and Hsc70 enhances the immune response to protein antigens

    Baek, Kyung-Hwa; Zhang, Haiying; Lee, Bo Ryeong; Kwon, Young-Guen; Ha, Sang-Jun; Shin, Injae

    2015-12-01

    The ATPase activities of Hsp70 and Hsc70 are known to be responsible for regulation of various biological processes. However, little is known about the roles of Hsp70 and Hsc70 in modulation of immune responses to antigens. In the present study, we investigated the effect of apoptozole (Az), a small molecule inhibitor of Hsp70 and Hsc70, on immune responses to protein antigens. The results show that mice administered with both protein antigen and Az produce more antibodies than those treated with antigen alone, showing that Az enhances immune responses to administered antigens. Treatment of mice with Az elicits production of antibodies with a high IgG2c/IgG1 ratio and stimulates the release of Th1 and Th2-type cytokines, suggesting that Az activates the Th1 and Th2 immune responses. The observations made in the present study suggest that inhibition of Hsp70 and Hsc70 activities could be a novel strategy designing small molecule-based adjuvants in protein vaccines.

  2. Role of recombination activating genes in the generation of antigen receptor diversity and beyond.

    Nishana, Mayilaadumveettil; Raghavan, Sathees C

    2012-12-01

    V(D)J recombination is the process by which antibody and T-cell receptor diversity is attained. During this process, antigen receptor gene segments are cleaved and rejoined by non-homologous DNA end joining for the generation of combinatorial diversity. The major players of the initial process of cleavage are the proteins known as RAG1 (recombination activating gene 1) and RAG2. In this review, we discuss the physiological function of RAGs as a sequence-specific nuclease and its pathological role as a structure-specific nuclease. The first part of the review discusses the basic mechanism of V(D)J recombination, and the last part focuses on how the RAG complex functions as a sequence-specific and structure-specific nuclease. It also deals with the off-target cleavage of RAGs and its implications in genomic instability. PMID:23039142

  3. Transformation and radiosensitivity of human diploid skin fibroblasts transfected with activated RAS oncogene and SV40 T-antigen

    Su, L.-N.; Little, J.B. (Harvard School of Public Health, Boston, MA (United States))

    1992-08-01

    Three normal human diploid cell strains were transfected with an activated Ha-ras oncogene (EJ ras) or SV40 T-antigen. Multiple clones were examined for morphological alterations, growth requirements, ability to grow under anchorage independent conditions, immortality and tumorigenicity in nude mice. Clones expressing SV40 T-antigen alone or in combination with ras protein p21 were significantly radioresistant as compared with their parent cells or clones transfected with the neo gene only. This radioresistant phenotype persisted in post-crisis, immortalized cell lines. These data suggest that expression of the SV40 T-antigen but not activated Ha-ras plays an important role in the radiosensitivity of human diploid cells. The radioresistant phenotype in SV40 T transfected cells was not related to the enhanced level of genetic instability seen in pre-crisis and newly immortalized cells, nor to the process of immortalization itself. (author).

  4. A new role for complement C3: regulation of antigen processing through an inhibitory activity.

    Villiers, Christian; Cretin, François,; Lefebvre, Nicole; Marche, Patrice; Villiers, Marie-Bernadette

    2008-01-01

    International audience Increasing evidence underlines the involvement of complement component C3 in the establishment of acquired immunity which appears to play a complex role and to act at different levels. As antigen proteolysis by antigen presenting cells is a key event in the control of antigen presentation efficiency, and consequently in the quality of the immune response, we investigated whether C3 could modulate this step. Our results demonstrate for the first time that C3 can inter...

  5. T cell activation. II. Activation of human T lymphoma cells by cross-linking of their MHC class I antigens

    Dissing, S; Geisler, C; Rubin, B; Plesner, T; Claesson, M H

    1990-01-01

    The present work demonstrates that antibody-induced cross-linking of MHC class I antigens on Jurkat T lymphoma cells leads to a rise in intracellular calcium (Cai2+) and, in the presence of phorbol ester (PMA), to IL-2 production and IL-2 receptor expression. The rise in Cai2+ exhibited a profile...... very different from that obtained after anti-CD3 antibody-induced activation suggesting that activation signals are transduced differently after binding of anti-CD3 antibody and class I cross-linking, respectively. However, when Cai2+ was examined in individual Jurkat cells by means of a digital image...... the T cell receptor complex and MHC class I molecules....

  6. Proteolytic activity of prostate-specific antigen (PSA towards protein substrates and effect of peptides stimulating PSA activity.

    Johanna M Mattsson

    Full Text Available Prostate-specific antigen (PSA or kallikrein-related peptidase-3, KLK3 exerts chymotrypsin-like proteolytic activity. The main biological function of PSA is the liquefaction of the clot formed after ejaculation by cleavage of semenogelins I and II in seminal fluid. PSA also cleaves several other substrates, which may explain its putative functions in prostate cancer and its antiangiogenic activity. We compared the proteolytic efficiency of PSA towards several protein and peptide substrates and studied the effect of peptides stimulating the activity of PSA with these substrates. An endothelial cell tube formation model was used to analyze the effect of PSA-degraded protein fragments on angiogenesis. We showed that PSA degrades semenogelins I and II much more efficiently than other previously identified protein substrates, e.g., fibronectin, galectin-3 and IGFBP-3. We identified nidogen-1 as a new substrate for PSA. Peptides B2 and C4 that stimulate the activity of PSA towards small peptide substrates also enhanced the proteolytic activity of PSA towards protein substrates. Nidogen-1, galectin-3 or their fragments produced by PSA did not have any effect on endothelial cell tube formation. Although PSA cleaves several other protein substrates, in addition to semenogelins, the physiological importance of this activity remains speculative. The PSA levels in prostate are very high, but several other highly active proteases, such as hK2 and trypsin, are also expressed in the prostate and may cleave protein substrates that are weakly cleaved by PSA.

  7. Engineered nanomaterials cause cytotoxicity and activation on mouse antigen presenting cells

    Nanomaterials improve everyday products but their safety for human health is poorly known. In this study we explored immunological effects of five different nanomaterials on antigen presenting cells (APC) in vitro. Nanomaterials studied were rutile titanium dioxide (TiO2), amorphous silica-coated rutile titanium dioxide (TiO2-silica), zinc oxide (ZnO), single-walled carbon nanotubes (SWCNT) and multi-walled carbon nanotubes (MWCNT). APCs included mouse macrophages (RAW 264.7 cell line) and murine bone marrow-derived dendritic cells (bmDC). All studied particles were cytotoxic to bmDCs, and ZnO, TiO2 and TiO2-silica-induced dose-dependently cell death also in macrophages. ZnO had the most drastic immunological effects leading to high expression of proinflammatory cytokine, IL-1β, and enhanced production of neutrophil chemoattractant CXCL-9 on both cell types. TiO2 and TiO2-silica stimulated the expression of IL-6, MIP-1α and TNF-α in macrophages, and increased their maturation, antigen presentation and co-stimulation activity. In contrast, SWCNT or MWCNT did not seem to have any significant immunological effects on the cell types studied suggesting that APCs might not be the target cells for carbon nanotubes. Due to diverse effects on different nanomaterials on immune cells we suggest that each new nanomaterial should be extensively studied in vitro and in vivo for risk assessment before their use in final products.

  8. Longitudinal microarray analysis of cell surface antigens on peripheral blood mononuclear cells from HIV+ individuals on highly active antiretroviral therapy

    Wang Bin

    2008-03-01

    Full Text Available Abstract Background The efficacy of highly active antiretroviral therapy (HAART determined by simultaneous monitoring over 100 cell-surface antigens overtime has not been attempted. We used an antibody microarray to analyze changes in the expression of 135 different cell-surface antigens overtime on PBMC from HIV+ patients on HAART. Two groups were chosen, one (n = 6 achieved sustainable response by maintaining below detectable plasma viremia and the other (n = 6 responded intermittently. Blood samples were collected over an average of 3 years and 5–8 time points were selected for microarray assay and statistical analysis. Results Significant trends over time were observed for the expression of 7 cell surface antigens (CD2, CD3epsilon, CD5, CD95, CD36, CD27 and CD28 for combined patient groups. Between groups, expression levels of 10 cell surface antigens (CD11a, CD29, CD38, CD45RO, CD52, CD56, CD57, CD62E, CD64 and CD33 were found to be differential. Expression levels of CD9, CD11a, CD27, CD28 and CD52, CD44, CD49d, CD49e, CD11c strongly correlated with CD4+ and CD8+ T cell counts, respectively. Conclusion Our findings not only detected markers that may have potential prognostic/diagnostic values in evaluating HAART efficacy, but also showed how density of cell surface antigens could be efficiently exploited in an array-like manner in relation to HAART and HIV-infection. The antigens identified in this study should be further investigated by other methods such as flow cytometry for confirmation as biological analysis of these antigens may help further clarify their role during HAART and HIV infection.

  9. Soluble Expression and Characterization of Biologically Active Bacillus anthracis Protective Antigen in Escherichia coli

    Nagendra Suryanarayana

    2016-01-01

    Full Text Available Bacillus anthracis secretory protein protective antigen (PA is primary candidate for subunit vaccine against anthrax. Attempts to obtain large quantity of PA from Escherichia coli expression system often result in the formation of insoluble inclusion bodies. Therefore, it is always better to produce recombinant proteins in a soluble form. In the present study, we have obtained biologically active recombinant PA in small scale E. coli shake culture system using three different expression constructs. The PA gene was cloned in expression vectors bearing trc, T5, and T7 promoters and transformed into their respective E. coli hosts. The growth conditions were optimized to obtain maximum expression of PA in soluble form. The expression construct PA-pET32c in DE3-pLysS E. coli host resulted in a maximum production of soluble PA (15 mg L−1 compared to other combinations. Purified PA was subjected to trypsin digestion and binding assay with lethal factor to confirm the protein’s functionality. Biological activity was confirmed by cytotoxicity assay on J774.1 cells. Balb/c mice were immunized with PA and the immunogenicity was tested by ELISA and toxin neutralization assay. This study highlights the expression of soluble and biologically active recombinant PA in larger quantity using simpler E. coli production platform.

  10. Soluble Expression and Characterization of Biologically Active Bacillus anthracis Protective Antigen in Escherichia coli.

    Suryanarayana, Nagendra; Vanlalhmuaka; Mankere, Bharti; Verma, Monika; Thavachelvam, Kulanthaivel; Tuteja, Urmil

    2016-01-01

    Bacillus anthracis secretory protein protective antigen (PA) is primary candidate for subunit vaccine against anthrax. Attempts to obtain large quantity of PA from Escherichia coli expression system often result in the formation of insoluble inclusion bodies. Therefore, it is always better to produce recombinant proteins in a soluble form. In the present study, we have obtained biologically active recombinant PA in small scale E. coli shake culture system using three different expression constructs. The PA gene was cloned in expression vectors bearing trc, T5, and T7 promoters and transformed into their respective E. coli hosts. The growth conditions were optimized to obtain maximum expression of PA in soluble form. The expression construct PA-pET32c in DE3-pLysS E. coli host resulted in a maximum production of soluble PA (15 mg L(-1)) compared to other combinations. Purified PA was subjected to trypsin digestion and binding assay with lethal factor to confirm the protein's functionality. Biological activity was confirmed by cytotoxicity assay on J774.1 cells. Balb/c mice were immunized with PA and the immunogenicity was tested by ELISA and toxin neutralization assay. This study highlights the expression of soluble and biologically active recombinant PA in larger quantity using simpler E. coli production platform. PMID:26966576

  11. Functional activation of the T-cell antigen receptor induces tyrosine phosphorylation of phospholipase C-gamma 1.

    Weiss, A; Koretzky, G; Schatzman, R C; Kadlecek, T

    1991-01-01

    Stimulation of the T-cell antigen receptor (TCR), which itself is not a protein-tyrosine kinase (PTK), activates a PTK and phospholipase C (PLC). Using the human T-cell leukemic line Jurkat and normal peripheral blood lymphocytes, we demonstrate that stimulation of the TCR specifically induces the recovery of PLC activity in eluates from anti-phosphotyrosine immunoprecipitates. Stimulation of the human muscarinic receptor, subtype 1, when expressed in Jurkat activates PLC through a guanine nu...

  12. Hepatitis B virus e antigen induces activation of rat hepatic stellate cells

    Zan, Yanlu [Center for Molecular Virology, CAS Key Laboratory of Pathogenic Microbiology and Immunology, Institute of Microbiology, Chinese Academy of Sciences, Beijing 100101 (China); University of Chinese Academy of Sciences, Beijing 100049 (China); Zhang, Yuxia, E-mail: yzhang@wehi.edu.au [Center for Molecular Virology, CAS Key Laboratory of Pathogenic Microbiology and Immunology, Institute of Microbiology, Chinese Academy of Sciences, Beijing 100101 (China); Tien, Po, E-mail: tienpo@sun.im.ac.cn [Center for Molecular Virology, CAS Key Laboratory of Pathogenic Microbiology and Immunology, Institute of Microbiology, Chinese Academy of Sciences, Beijing 100101 (China)

    2013-06-07

    Highlights: •HBeAg expression in HSCs induced production of ECM protein and liver fibrotic markers. •The activation and proliferation of HSCs were mediated by TGF-β. •HBeAg protein purified from cell medium directly activated HSCs. -- Abstract: Chronic hepatitis B virus infection is a major cause of hepatic fibrosis, leading to liver cirrhosis and hepatocellular carcinoma. Hepatitis B virus e antigen (HBeAg) is an accessory protein of HBV, not required for viral replication but important for natural infection in vivo. Hepatic stellate cells (HSCs) are the major producers of excessive extracellular matrix during liver fibrogenesis. Therefore, we examined the influence of HBeAg on HSCs. The rat HSC line HSC-T6 was transfected with HBeAg plasmids, and expression of α-smooth muscle actin, collagen I, transforming growth factor-β1 (TGF-β), and tissue inhibitors of metalloproteinase 1 (TIMP-1) was investigated by quantitative real-time PCR. The proliferation of HSCs was determined by MTS analysis. HBeAg transduction induced up-regulation of these fibrogenic genes and proliferation of HSCs. We found that HBeAg induced TGF-β secretion in HSCs, and the activation of HSCs was prevented by a neutralizing anti-TGF-β antibody. Depletion and addition of HBeAg protein in conditioned medium from HSC-T6 cells transduced with HBeAg indicated that HBeAg directly induced the activation and proliferation of rat primary HSCs. Taken together, HBeAg induces the activation and proliferation of HSCs, mainly mediated by TGF-β, and HBeAg protein purified from cell medium can directly activate HSCs.

  13. Hepatitis B virus e antigen induces activation of rat hepatic stellate cells

    Highlights: •HBeAg expression in HSCs induced production of ECM protein and liver fibrotic markers. •The activation and proliferation of HSCs were mediated by TGF-β. •HBeAg protein purified from cell medium directly activated HSCs. -- Abstract: Chronic hepatitis B virus infection is a major cause of hepatic fibrosis, leading to liver cirrhosis and hepatocellular carcinoma. Hepatitis B virus e antigen (HBeAg) is an accessory protein of HBV, not required for viral replication but important for natural infection in vivo. Hepatic stellate cells (HSCs) are the major producers of excessive extracellular matrix during liver fibrogenesis. Therefore, we examined the influence of HBeAg on HSCs. The rat HSC line HSC-T6 was transfected with HBeAg plasmids, and expression of α-smooth muscle actin, collagen I, transforming growth factor-β1 (TGF-β), and tissue inhibitors of metalloproteinase 1 (TIMP-1) was investigated by quantitative real-time PCR. The proliferation of HSCs was determined by MTS analysis. HBeAg transduction induced up-regulation of these fibrogenic genes and proliferation of HSCs. We found that HBeAg induced TGF-β secretion in HSCs, and the activation of HSCs was prevented by a neutralizing anti-TGF-β antibody. Depletion and addition of HBeAg protein in conditioned medium from HSC-T6 cells transduced with HBeAg indicated that HBeAg directly induced the activation and proliferation of rat primary HSCs. Taken together, HBeAg induces the activation and proliferation of HSCs, mainly mediated by TGF-β, and HBeAg protein purified from cell medium can directly activate HSCs

  14. Transcription Activity of Ectogenic Human Carcinoembryonic Antigen Promoter in Lung Adenocarcinoma Cells A549

    XIONG Weining; FANG Huijuan; XU Yongjian; XIONG Shendao; CAO Yong; SONG Qingfeng; ZENG Daxiong; ZHANG Huilan

    2006-01-01

    The transcription activity of ectogenic human carcinoembryonic antigen (CEA) promoter in lung adenocarcinoma cells A549 was investigated for the further gene-targeting therapy. The reporter gene green fluorescent protein (GFP) driven by CEA promoter and human cytomegalovirus (CMV) promoter were relatively constructed and named plasmid pCEA-EGFP and pCMV-GFP respectively. The intensity of fluorescence was detected by fluorescence microscope and flow cytometry analysis after the pCEA-GFP and pSNAV-GFP plasmids were transfected into A549 cells through liposome respectively. The results showed (4.08±0.63) % of the A549 cells transfected with pCEA-AFP plasmid expressed, significantly lower than that of the A549 cells transfected with pCMV-GFP [(43.27±3.54) %]. It was suggested that ectogenic human CEA promoter in lung adenocarcinoma cells A549 was weakly expressed. The distinct specificity of CEA promoter in CEA high expression cells was regarded as a tool in selective gene therapy, but the transcription activity of ectogenic human CEA promoter was needed to increase in the future.

  15. Merkel Cell Polyomavirus Large T Antigen Has Growth-Promoting and Inhibitory Activities

    Cheng, Jingwei; Rozenblatt-Rosen, Orit; Paulson, Kelly G.; Nghiem, Paul; DeCaprio, James A.

    2013-01-01

    Merkel cell carcinoma (MCC) is a rare and aggressive form of skin cancer. In at least 80% of all MCC, Merkel cell polyomavirus (MCPyV) DNA has undergone clonal integration into the host cell genome, and most tumors express the MCPyV large and small T antigens. In all cases of MCC reported to date, the integrated MCPyV genome has undergone mutations in the large T antigen. These mutations result in expression of a truncated large T antigen that retains the Rb binding or LXCXE motif but deletes...

  16. Preparation, Characterization, and Determination of Immunological Activities of Transfer Factor Specific to Human Sperm Antigen

    Jianwei Zhou

    2013-01-01

    Full Text Available Objective. The objective of this study was to prepare, characterize, and determine immunological activities of specific transfer factor (STF specific to human sperm antigen (HSA for the preparation of antisperm contraceptive vaccine that can be used as an immunocontraceptive. Methods. HSA-STF was prepared using the spleens of rabbits vaccinated with HSA. The specific immunological activities were examined by lymphocyte proliferation test (LPT, leukocyte adhesion inhibition test (LAIT, and by determining the concentrations of IL-4, γ-IFN, and IL-21. HSA-STF was a helveolous substance, having a pH value of 7.0±0.4 and UV absorption maxima at 258 ± 6 nm. It contained seventeen amino acids; glycine and glutamic acids were the highest in terms of concentrations (38.8 μg/mL and 36.3 μg/mL, resp.. Results. The concentration of polypeptide was 2.34±0.31 mg/mL, and ribose was 0.717±0.043 mg/mL. The stimulation index for lymphocyte proliferation test was 1.84, and the leukocyte adhesion inhibition rate was 37.7%. There was a statistically significant difference between the cultural lymphocytes with HSA-STF and non-HSA-STF for γ-IFN and IL-21 (P0.05. Conclusion. HSA-STF was prepared and characterized successfully. It had immunological activity which could transfer the immune response specific to HSA and prove to be a potential candidate for the development of male immunocontraceptive agents.

  17. Definition of a physiologic aging autoantigen by using synthetic peptides of membrane protein band 3: localization of the active antigenic sites.

    Kay, M M; Marchalonis, J J; Hughes, J; Watanabe, K; Schluter, S F

    1990-08-01

    Senescent cell antigen (SCA), an aging antigen, is a protein that appears on old cells and marks them for removal by the immune system in mammals. It is derived from band 3, a ubiquitous membrane transport protein found in diverse cell types and tissues. We have used synthetic peptides to identify aging antigenic sites on band 3, using a competitive inhibition assay and immunoblotting with IgG directed against the aging antigen on old cells. Results indicate that: (i) the active antigenic sites of the aging antigen reside on membrane protein band 3 residues that are extracellular regions implicated in anion transport (residues 538-554 and 788-827); (ii) a putative ankyrin-binding-region peptide is not involved in SCA activity; and (iii) carbohydrate moieties are not required for the antigenicity or recognition of SCA because synthetic peptides alone abolish binding of senescent cell IgG to erythrocytes. One of the putative transport sites that contributes to the aging antigen is located toward the carboxyl terminus. A model of band 3 is presented. Localization of the active antigenic site on the band 3 molecule facilitates definition of the molecular changes occurring during aging that initiate molecular as well as cellular degeneration. PMID:1696010

  18. Infection of SCID mice with Mycobacterium leprae and control with antigen-activated "immune" human peripheral blood mononuclear cells.

    Converse, P J; Haines, V L; Wondimu, A; Craig, L E; Meyers, W M

    1995-03-01

    The SCID (severe combined immunodeficient) mouse lacks both B and T cells and tolerates injected mononuclear cells from humans, the principal hosts of Mycobacterium leprae. A SCID mouse model of leprosy could be useful to investigate potential vaccine strategies using human cells in a context in which the growth of the organism is monitored. Initial experiments determined that SCID mice are more susceptible than normal mice to infection and dissemination of M. leprae. Cells from humans, either BCG vaccinated or from countries where leprosy is endemic, were stimulated in vitro with a number of mycobacterial antigens--whole M. leprae, M. leprae cell walls, purified protein derivative of M. tuberculosis, and Mycobacterium bovis BCG--and tested for proliferation and production of interleukin-6, tumor necrosis factor alpha, and gamma interferon. Cell walls were the most efficient and consistent in inducing all of these activities. In vitro-activated human cells retain function better after injection into SCID mice than nonactivated cells. To test the ability of cells to affect the growth of M. leprae in the footpads of SCID mice, cells from a known responder to mycobacterial antigens and from a nonresponder were activated by M. leprae cell wall antigens. The cells were harvested and coinjected with fresh M. leprae into the right hind footpads of SCID mice. After 3 months, there was no growth of M. leprae in the footpads of mice coinjected with cells from the mycobacterial antigen responder, while growth was uninhibited in mice receiving cells from the nonresponder. Future experiments will determine requirements for antigen specificity in inhibiting M. leprae multiplication. PMID:7868226

  19. Stimulation of T-cell activation by UV-treated, antigen-pulsed macrophages: evidence for a requirement for antigen processing and interleukin 1 secretion

    The nature of the defect(s) in the ability of UV-treated guinea pig macrophages to stimulate the proliferative response of guinea pig T cells to soluble protein antigens was investigated. T cells proliferated vigorously when cultured with peritoneal exudate cells (PEC) which had been pulsed with soluble protein antigens, but failed to proliferate when cultured with soluble antigen or with antigen-pulsed, UV-treated PEC. UV-treated macrophages were unable to secrete interleukin 1 (IL-1). Addition of IL-1 partially restored the T-cell proliferative response stimulated by antigen-pulsed, UV-treated PEC. However, IL-1 was able to restore such a response only when the PEC were pulsed with antigen before being exposed to UV. Similar results were obtained when antigen-pulsed PEC were used to stimulate T cells to secrete interleukin 2 (IL-2). These results demonstrate that UV-treated macrophages are defective both in their ability to properly process and present antigen for T-cell recognition and in their ability to secrete IL-1

  20. A New Method to Determine Antigen-Specific CD8+ T Cell Activity in Vivo by Hydrodynamic Injection

    Moriya Tsuji

    2012-01-01

    Full Text Available Hydrodynamic tail vein (HTV delivery is a simple and rapid tail vein injection method of a high volume of naked plasmid DNA resulting in high levels of foreign gene expression in organs, especially the liver. Compared to other organs, HTV delivery results in more than a 1000-fold higher transgene expression in liver. After being bitten by malaria-infected mosquitoes, malaria parasites transiently infect the host liver and form the liver stages. The liver stages are known to be the key target for CD8+ T cells that mediate protective anti-malaria immunity in an animal model. Therefore, in this study, we utilized the HTV delivery technique as a tool to determine the in vivo cytotoxic effect of malaria antigen-specific CD8+ T cells. Two weeks after mice were immunized with recombinant adenoviruses expressing malarial antigens, the immunized mice as well as naïve mice were challenged by HTV delivery of naked plasmid DNA co-encoding respective antigen together with luciferase using dual promoters. Three days after the HTV challenge, non-invasive whole-body bioluminescent imaging was performed. The images demonstrate in vivo activity of CD8+ T cells against malaria antigen-expressing cells in liver.

  1. Recruitment of Cbl-b to B cell antigen receptor couples antigen recognition to Toll-like receptor 9 activation in late endosomes.

    Margaret Veselits

    Full Text Available Casitas B-lineage lymphoma-b (Cbl-b is a ubiquitin ligase (E3 that modulates signaling by tagging molecules for degradation. It is a complex protein with multiple domains and binding partners that are not involved in ubiquitinating substrates. Herein, we demonstrate that Cbl-b, but not c-Cbl, is recruited to the clustered B cell antigen receptor (BCR and that Cbl-b is required for entry of endocytosed BCRs into late endosomes. The E3 activity of Cbl-b is not necessary for BCR endocytic trafficking. Rather, the ubiquitin associated (UBA domain is required. Furthermore, the Cbl-b UBA domain is sufficient to confer the receptor trafficking functions of Cbl-b on c-Cbl. Cbl-b is also required for entry of the Toll-like receptor 9 (TLR9 into late endosomes and for the in vitro activation of TLR9 by BCR-captured ligands. These data indicate that Cbl-b acts as a scaffolding molecule to coordinate the delivery of the BCR and TLR9 into subcellular compartments required for productively delivering BCR-captured ligands to TLR9.

  2. Activation/Inhibition of mast cells by supra-optimal antigen concentrations.

    Huber, Michael

    2013-01-01

    Mast cells (MCs) are tissue resident cells of hemopoietic origin and are critically involved in allergic diseases. MCs bind IgE by means of their high-affinity receptor for IgE (FcεRI). The FcεRI belongs to a family of multi-chain immune recognition receptors and is activated by cross-linking in response to multivalent antigens (Ags)/allergens. Activation of the FcεRI results in immediate release of preformed granular substances (e.g. histamine, heparin, and proteases), generation of arachidonic acid metabolites, and production of pro-inflammatory cytokines. The FcεRI shows a remarkable, bell-shaped dose-response behavior with weak induction of effector responses at both low and high (so-called supra-optimal) Ag concentrations. This is significantly different from many other receptors, which reach a plateau phase in response to high ligand concentrations. To explain this unusual dose-response behavior of the FcεRI, scientists in the past have drawn parallels to so-called precipitin curves resulting from titration of Ag against a fixed concentration of antibody (Ab) in solution (a.k.a. Heidelberger curves). Thus, for high, supra-optimal Ag concentrations one could assume that every IgE-bound FcεRI formed a monovalent complex with "its own Ag", thus resulting in marginal induction of effector functions due to absence of receptor cross-linking. However, this was never proven to be the case. More recently, careful studies of FcεRI activation and signaling events in MCs in response to supra-optimal Ag concentrations have suggested a molecular explanation for the descending part of this bell-shaped curve. It is obvious now that extensive FcεRI/IgE/Ag clusters are formed and inhibitory molecules and signalosomes are engaged in response to supra-optimal cross-linking (amongst them the Src family kinase Lyn and the inositol-5'-phosphatase SHIP1) and they actively down-regulate MC effector responses. Thus, the analysis of MC signaling triggered by supra

  3. Mitochondrial H2O2 in Lung Antigen-Presenting Cells Blocks NF-κB Activation to Prevent Unwarranted Immune Activation

    Anupriya Khare

    2016-05-01

    Full Text Available Inhalation of environmental antigens such as allergens does not always induce inflammation in the respiratory tract. While antigen-presenting cells (APCs, including dendritic cells and macrophages, take up inhaled antigens, the cell-intrinsic molecular mechanisms that prevent an inflammatory response during this process, such as activation of the transcription factor NF-κB, are not well understood. Here, we show that the nuclear receptor PPARγ plays a critical role in blocking NF-κB activation in response to inhaled antigens to preserve immune tolerance. Tolerance induction promoted mitochondrial respiration, generation of H2O2, and suppression of NF-κB activation in WT, but not PPARγ-deficient, APCs. Forced restoration of H2O2 in PPARγ-deficient cells suppressed IκBα degradation and NF-κB activation. Conversely, scavenging reactive oxygen species from mitochondria promoted IκBα degradation with loss of regulatory and promotion of inflammatory T cell responses in vivo. Thus, communication between PPARγ and the mitochondria maintains immune quiescence in the airways.

  4. Engineered hepatitis B virus surface antigen L protein particles for in vivo active targeting of splenic dendritic cells

    Matsuo H

    2012-07-01

    Full Text Available Hidenori Matsuo,1 Nobuo Yoshimoto,1 Masumi Iijima,1 Tomoaki Niimi,1 Joohee Jung,2,3 Seong-Yun Jeong,3 Eun Kyung Choi,3,4 Tomomitsu Sewaki,5 Takeshi Arakawa,6,7 Shun’ichi Kuroda11Graduate School of Bioagricultural Sciences, Nagoya University, Nagoya, Japan; 2College of Pharmacy, Duksung Women’s University, Seoul, South Korea; 3Institute for Innovative Cancer Research, ASAN Medical Center, Seoul, South Korea; 4Department of Radiation Oncology, University of Ulsan College of Medicine, Seoul, South Korea; 5GenoLac BL Corporation, Okinawa, Japan; 6COMB, Tropical Biosphere Research Center, 7Graduate School of Medicine, University of the Ryukyus, Okinawa, JapanAbstract: Dendritic cells (DCs are key regulators of adaptive T-cell responses. By capturing exogenous antigens and presenting antigen-derived peptides via major histocompatibility complex molecules to naïve T cells, DCs induce antigen-specific immune responses in vivo. In order to induce effective host immune responses, active delivery of exogenous antigens to DCs is considered important for future vaccine development. We recently generated bionanocapsules (BNCs consisting of hepatitis B virus surface antigens that mediate stringent in vivo cell targeting and efficient endosomal escape, and after the fusion with liposomes (LP containing therapeutic materials, the BNC-LP complexes deliver them to human liver-derived tissues in vivo. BNCs were further modified to present the immunoglobulin G (IgG Fc-interacting domain (Z domain derived from Staphylococcus aureus protein A in tandem. When mixed with IgGs, modified BNCs (ZZ-BNCs displayed the IgG Fv regions outwardly for efficient binding to antigens in an oriented-immobilization manner. Due to the affinity of the displayed IgGs, the IgG-ZZ-BNC complexes accumulated in specific cells and tissues in vitro and in vivo. After mixing ZZ-BNCs with antibodies against DCs, we used immunocytochemistry to examine which antibodies delivered ZZ-BNCs to

  5. Caspase-1 Dependent IL-1β Secretion and Antigen-Specific T-Cell Activation by the Novel Adjuvant, PCEP

    Sunita Awate

    2014-06-01

    Full Text Available The potent adjuvant activity of the novel adjuvant, poly[di(sodiumcarboxylatoethylphenoxyphosphazene] (PCEP, with various antigens has been reported previously. However, very little is known about its mechanisms of action. We have recently reported that intramuscular injection of PCEP induces NLRP3, an inflammasome receptor gene, and inflammatory cytokines, including IL-1β and IL-18, in mouse muscle tissue. Caspase-1 is required for the processing of pro-forms of IL-1β and IL-18 into mature forms and is a critical constituent of the NLRP3 inflammasome. Hence, in the present study, we investigated the role of caspase-1 in the secretion of IL-1β and IL-18 in PCEP-stimulated splenic dendritic cells (DCs. Caspase inhibitor YVAD-fmk-treated splenic DCs showed significantly reduced IL-1β and IL-18 secretion in response to PCEP stimulation. Further, PCEP had no effect on the expression of MHC class II or co-stimulatory molecules, CD86 and CD40, suggesting that PCEP does not induce DC maturation. However, PCEP directly activated B-cells to induce significant production of IgM. In addition, PCEP+ovalbumin (OVA immunized mice showed significantly increased production of antigen-specific IFN-γ by CD4+ and CD8+ T-cells. We conclude that PCEP activates innate immunity, leading to increased antigen-specific T-cell responses.

  6. Research Upregulation of CD23 (FcεRII) Expression in Human Airway Smooth Muscle Cells (huASMC) in Response to IL-4, GM-CSF, and IL-4/GM-CSF

    Belleau, Joseph T; Gandhi, Radha K; McPherson, Holly M; Lew, D Betty

    2005-01-01

    Background Airway smooth muscle cells play a key role in remodeling that contributes to airway hyperreactivity. Airway smooth muscle remodeling includes hypertrophy and hyperplasia. It has been previously shown that the expression of CD23 on ASMC in rabbits can be induced by the IgE component of the atopic serum. We examined if other components of atopic serum are capable of inducing CD23 expression independent of IgE. Methods Serum starved huASMC were stimulated with either IL-4, GM-CSF, IL-13, IL-5, PGD2, LTD4, tryptase or a combination of IL-4, IL-5, IL-13 each with GM-CSF for a period of 24 h. CD23 expression was analyzed by flow cytometry, western blot, and indirect immunofluorescence. Results The CD23 protein expression was upregulated in huASMC in response to IL-4, GM-CSF, and IL-4/GM-CSF. The percentage of cells with increased fluorescence intensity above the control was 25.1 ± 4.2% (IL-4), 15.6 ± 2.7% (GM-CSF) and 32.9 ± 13.9% (IL-4/GMCSF combination)(n = 3). The protein content of IL-4/GMCSF stimulated cells was significantly elevated. Expression of CD23 in response to IL-4, GM-CSF, IL-4/GM-CSF was accompanied by changes in cell morphology including depolymerization of isoactin fibers, cell spreading, and membrane ruffling. Western blot revealed abundant expression of the IL-4Rα and a low level expression of IL-2Rγc in huASMC. Stimulation with IL-4 resulted in the phosphorylation of STAT-6 and an increase in the expression of the IL-2Rγc. Conclusion CD23 on huASMC is upregulated by IL-4, GM-CSF, and IL-4/GM-CSF. The expression of CD23 is accompanied by an increase in cell volume and an increase in protein content per cell, suggesting hypertrophy. Upregulation of CD23 by IL-4/GM-CSF results in phenotypic changes in huASMC that could play a role in cell migration or a change in the synthetic function of the cells. Upregulation of CD23 in huASMC by IL-4 and GM-CSF can contribute to changes in huASMC and may provide an avenue for new therapeutic options

  7. Research Upregulation of CD23 (FcεRII Expression in Human Airway Smooth Muscle Cells (huASMC in Response to IL-4, GM-CSF, and IL-4/GM-CSF

    Lew D Betty

    2005-05-01

    Full Text Available Abstract Background Airway smooth muscle cells play a key role in remodeling that contributes to airway hyperreactivity. Airway smooth muscle remodeling includes hypertrophy and hyperplasia. It has been previously shown that the expression of CD23 on ASMC in rabbits can be induced by the IgE component of the atopic serum. We examined if other components of atopic serum are capable of inducing CD23 expression independent of IgE. Methods Serum starved huASMC were stimulated with either IL-4, GM-CSF, IL-13, IL-5, PGD2, LTD4, tryptase or a combination of IL-4, IL-5, IL-13 each with GM-CSF for a period of 24 h. CD23 expression was analyzed by flow cytometry, western blot, and indirect immunofluorescence. Results The CD23 protein expression was upregulated in huASMC in response to IL-4, GM-CSF, and IL-4/GM-CSF. The percentage of cells with increased fluorescence intensity above the control was 25.1 ± 4.2% (IL-4, 15.6 ± 2.7% (GM-CSF and 32.9 ± 13.9% (IL-4/GMCSF combination(n = 3. The protein content of IL-4/GMCSF stimulated cells was significantly elevated. Expression of CD23 in response to IL-4, GM-CSF, IL-4/GM-CSF was accompanied by changes in cell morphology including depolymerization of isoactin fibers, cell spreading, and membrane ruffling. Western blot revealed abundant expression of the IL-4Rα and a low level expression of IL-2Rγc in huASMC. Stimulation with IL-4 resulted in the phosphorylation of STAT-6 and an increase in the expression of the IL-2Rγc. Conclusion CD23 on huASMC is upregulated by IL-4, GM-CSF, and IL-4/GM-CSF. The expression of CD23 is accompanied by an increase in cell volume and an increase in protein content per cell, suggesting hypertrophy. Upregulation of CD23 by IL-4/GM-CSF results in phenotypic changes in huASMC that could play a role in cell migration or a change in the synthetic function of the cells. Upregulation of CD23 in huASMC by IL-4 and GM-CSF can contribute to changes in huASMC and may provide an avenue

  8. Self-antigen recognition by TGFβ1-deficient T cells causes their activation and systemic inflammation

    Bommireddy, Ramireddy; Pathak, Leena J; Martin, Jennifer; Ormsby, Ilona; Engle, Sandra J; Gregory P. Boivin; Babcock, George F.; Eriksson, Anna U.; Singh, Ram R; DOETSCHMAN, THOMAS

    2006-01-01

    To investigate whether the multifocal inflammatory disease in TGFβ1-deficient mice is caused by self-antigen (self-Ag)-specific autoreactive T cells, or whether it is caused by antigen independent, spontaneous hyperactivation of T cells, we have generated Tgfb1−/− and Tgfb1−/− Rag1−/− mice expressing the chicken OVA-specific TCR transgene (DO11.10). On a Rag1-sufficient background, Tgfb1−/− DO11.10 mice develop a milder inflammation than do Tgfb1−/− mice, and their T cells display a less acti...

  9. Major histocompatibility complex class II (DR) antigen and costimulatory molecules on in vitro and in vivo activated human polymorphonuclear neutrophils

    Sandilands, Gavin P; McCrae, Jame; Hill, Kathryn; Perry, Martin; Baxter, Derek

    2006-01-01

    We have previously shown that normal human peripheral blood polymorphonuclear neutrophils (PMNs) contain cytoplasmic ‘stores’ of three key molecules normally associated with antigen presentation and T-cell costimulation, i.e. major histocompatibility complex class II (DR) antigen, CD80 (B7-1) and CD86 (B7-2). These cytoplasmic molecules were found to translocate to the cell surface within a few minutes following cross-linking (X-L) of Mac-1: an early neutrophil activation signal. In this study we have compared X-L of Mac −1 in parallel with four other well documented in vitro neutrophil activators: phorbol myristate acetate, N-formyl methionyl leucyl phenylalanine, lipopolysaccharide, and phagocytosis of immunoglobulin G–Latex particles. In addition, we have used paired samples of neutrophils obtained from peripheral blood (as a control) and synovial fluid from patients with rheumatoid arthritis as a source of in vivo activated cells. With the exception of phagocytosis, all activators resulted in the rapid (within 30 min) generation of two populations of activated neutrophils (designated P1 and P2) based on flow-cytometry measurements of size, granularity and phenotype. Significant up-regulation of DR and costimulatory molecules was observed, predominantly on P2 cells, with all activators except phagocytosis. CD80 and CD86 were noted to respond to the various activation signals in a different pattern suggesting that their intracellular granule location may be different. Dual-staining confocal laser microscopy studies showed that CD80 is largely confined to secretory vesicles (SVs) while CD86 appears to have a much wider distribution being found in SVs and within secondary (specific) and primary (azurophilic) granules. Increased surface expression of these antigens was also observed on P2 synovial fluid neutrophils appearing as large heterogeneous clusters on the cell surface when visualized by confocal laser microscopy. PMID:17034427

  10. Immunogenic and antigenic activity of an experimental oral rabies vaccine prepared from the strain Vnukovo-32/107.

    Svrcek, S; Durove, A; Ondrejka, R; Závadová, J; Süliová, J; Benísek, Z; Vrtiak, O J; Feketeová, J; Mad'ar, M

    1995-03-01

    The immunogenic and antigenic activity of an experimental live oral rabies vaccine prepared from the strain Vnukovo-32/107 was evaluated on the basis of results obtained in 3 sets of experiments. These were carried out as model experiments on white mice, then on target animals--red foxes (Vulpes vulpes) and a related species--farm-bred polar foxes (Alopex lagopus). For quantitative determination of the immunogenic activity of the orally or subcutaneously administered rabies vaccines in model experiments on mice a method was used that had been developed in our laboratory. Antibodies were detected and quantified by an ELISA kit that had also been developed in our lab. Tenacity of the experimental vaccine (infectious tissue culture medium after yolk addition) was verified at different temperatures; the effects of storage temperature upon virus titre and immunogenic activity were investigated. An important part of the experiments--evaluation of the antigenic and immunogenic activity of the live vaccine at oral vaccination (vaccination baits, conditions simulating field vaccination) was carried out in foxes. The immunogenic activity (challenge experiments with a street virus on day 180 and 360 after vaccination) was evaluated in common foxes (Vulpes vulpes). The results document a high immunogenic and antigenic activity of the experimental live oral rabies vaccine. The strain Vnukovo-32/107 is suitable for the industrial manufacturing of vaccination baits. In the target species--common foxes challenged on day 180 after primovaccination an 83% protection was observed. Challenge on day 180 after revaccination (or day 360 after primovaccination), the orally immunized foxes proved to be 100% protected. For parallel evaluation of the immunogenic activity of an oral vaccine and for antibody titration it is recommended to employ the quantitative mice test and an ELISA technique, respectively. PMID:7762124

  11. Standardization of natural mycolic acid antigen composition and production for use in biomarker antibody detection to diagnose active tuberculosis.

    Ndlandla, F L; Ejoh, V; Stoltz, A C; Naicker, B; Cromarty, A D; van Wyngaardt, S; Khati, M; Rotherham, L S; Lemmer, Y; Niebuhr, J; Baumeister, C R; Al Dulayymi, J R; Swai, H; Baird, M S; Verschoor, J A

    2016-08-01

    Mycobacterium tuberculosis, the causative agent of tuberculosis, is characterized by the abundance of species specific, antigenic cell wall lipids called mycolic acids. These wax-like molecules all share an identical, amphiphilic mycolic motif, but have different functional groups in a long hydrophobic hydrocarbon mero-chain that divide them into three main classes: alpha-, keto- and methoxy-mycolic acids. Whereas alpha-mycolic acids constitutively maintain an abundance of around 50%, the ratio of methoxy- to keto-mycolic acid types may vary depending on, among other things, the growth stage of M. tuberculosis. In human patients, antibodies to mycolic acids have shown potential as diagnostic serum biomarkers for active TB. Variations in mycolic acid composition affect the antigenic properties and can potentially compromise the precision of detection of anti-mycolic acids antibodies in patient sera to natural mixtures. We demonstrate this here with combinations of synthetic mycolic acid antigens, tested against TB patient and control sera. Combinations of methoxy- and α-mycolic acids are more antigenic than combinations of keto- and α-mycolic acids, showing the former to give a more sensitive test for TB biomarker antibodies. Natural mixtures of mycolic acids isolated from mature cultures of M. tuberculosis H37Rv give the same sensitivity as that with synthetic methoxy- and α-mycolic acids in combination, in a surface plasmon resonance inhibition biosensor test. To ensure that the antigenic activity of isolates of natural mycolic acids is reproducible, we cultured M. tuberculosis H37Rv on Middlebrook 7H10 solid agar plates to stationary growth phase in a standardized, optimal way. The proportions of mycolic acid classes in various batches of the isolates prepared from these cultures were compared to a commercially available natural mycolic acid isolate. LC-MS/MS and NMR data for quantitation of mycolic acids class compositions show that the variation in batches

  12. Inhibition of Class II Major Histocompatibility Complex Antigen Processing by Escherichia coli Heat-Labile Enterotoxin Requires an Enzymatically Active A Subunit

    Matousek, Milita P.; Nedrud, John G.; Cieplak, Witold; Harding, Clifford V.

    1998-01-01

    Escherichia coli heat-labile enterotoxin (LT) and cholera toxin (CT) were found to inhibit intracellular antigen processing. Processing was not inhibited by mutant LT with attenuated ADP-ribosyltransferase activity, CT B or LT B subunit, which enhanced presentation of preexisting cell surface peptide-class II major histocompatibility complex complexes. Inhibition of antigen processing correlated with A subunit ADP-ribosyltransferase activity. PMID:9632629

  13. Research Upregulation of CD23 (FcεRII) Expression in Human Airway Smooth Muscle Cells (huASMC) in Response to IL-4, GM-CSF, and IL-4/GM-CSF

    Lew D Betty; McPherson Holly M; Gandhi Radha K; Belleau Joseph T

    2005-01-01

    Abstract Background Airway smooth muscle cells play a key role in remodeling that contributes to airway hyperreactivity. Airway smooth muscle remodeling includes hypertrophy and hyperplasia. It has been previously shown that the expression of CD23 on ASMC in rabbits can be induced by the IgE component of the atopic serum. We examined if other components of atopic serum are capable of inducing CD23 expression independent of IgE. Methods Serum starved huASMC were stimulated with either IL-4, GM...

  14. Appearance of an inhibitory cell nuclear antigen in rat and human serum during variable degrees of hepatic regenerative activity

    1999-01-01

    AIM To determine whether proliferating cell nuclear antigen (PCNA) is present in the peripheral circulation and whether PCNA levels correlate with enhanced regenerative activity.METHODS In animal studies, adult male Sprague-Dawley rats (n=3-4/ group) were sacrificed at 0, 12, 24, 36, 48, 72 and 96 hours following 70% partial hepatectomy. At each interval, sera were analyzed by Western blot for PCNA by two monoclonal antibodies (PC-10 and 19F-4). In human studies, sera from 4 patients with liver cirrhosis and 4 healthy controls were tested in a similar manner.RESULTS The PC-10 monoclonal antibody identified a protein with a molecular mass of 120 KD which remained stable in rat sera for 24 hours following partial hepatectomy, then increased 1.5-fold at 48 hours prior to returning to baseline at 96 hours after partial hepatectomy. However, it was not detected in the sera of patients with or without liver disease. In the 19F-4 monoclonal antibody, a protein with a molecular mass of approximately 46 KD was found. which was present in rat sera prior to partial hepatectomy and for 12 hours after surgery. Thereafter, levels fell by approximately 50% at 24 hours, 65% at 36 hours and 75% at 48 hours where they remained until 96 hours after partial hepatectomy. The decrease in levels correlated with the extent of partial hepatectomy. In human sera, the appearance of this inhibitory cell nuclear antigen (ICNA) was higher in the sera of patients with cirrhosis than in healthy controls.CONCLUSION The PC-10 monoclonal antibody can detect a protein in the circulation when active hepatic regenerative activity is taking place. The 19F-4 monoclonal antibody, however, identifies a protein in both rat and human sera that inversely correlates with hepatic regenerative activity. This protein which is tentatively referred to as inhibitory cell nuclear antigen (ICNA) may be used in documenting the extent of suppression of hepatic regeneration.

  15. Improved Activation toward Primary Colorectal Cancer Cells by Antigen-Specific Targeting Autologous Cytokine-Induced Killer Cells

    Claudia Schlimper

    2012-01-01

    Full Text Available Adoptive therapy of malignant diseases with cytokine-induced killer (CIK cells showed promise in a number of trials; the activation of CIK cells from cancer patients towards their autologous cancer cells still needs to be improved. Here, we generated CIK cells ex vivo from blood lymphocytes of colorectal cancer patients and engineered those cells with a chimeric antigen receptor (CAR with an antibody-defined specificity for carcinoembryonic antigen (CEA. CIK cells thereby gained a new specificity as defined by the CAR and showed increase in activation towards CEA+ colon carcinoma cells, but less in presence of CEA− cells, indicated by increased secretion of proinflammatory cytokines. Redirected CIK activation was superior by CAR-mediated CD28-CD3ζ than CD3ζ signaling only. CAR-engineered CIK cells from colon carcinoma patients showed improved activation against their autologous, primary carcinoma cells from biopsies resulting in more efficient tumour cell lysis. We assume that adoptive therapy with CAR-modified CIK cells shows improved selectivity in targeting autologous tumour lesions.

  16. Loss of proliferation and antigen presentation activity following internalization of polydispersed carbon nanotubes by primary lung epithelial cells.

    Mandavi Kumari

    Full Text Available Interactions between poly-dispersed acid functionalized single walled carbon nanotubes (AF-SWCNTs and primary lung epithelial (PLE cells were studied. Peritoneal macrophages (PMs, known phagocytic cells were used as positive controls in this study. Recovery of live cells from cultures of PLE cells and PMs was significantly reduced in the presence of AF-SWCNTs, in a time and dose dependent manner. Both PLE cells as well as PMs could take up fluorescence tagged AF-SWCNTs in a time dependent manner and this uptake was significantly blocked by cytochalasin D, an agent that blocks the activity of acto-myosin fibers and therefore the phagocytic activity of cells. Confocal microscopic studies confirmed that AF-SWCNTs were internalized by both PLE cells and PMs. Intra-trachially instilled AF-SWCNTs could also be taken up by lung epithelial cells as well as alveolar macrophages. Freshly isolated PLE cells had significant cell division activity and cell cycling studies indicated that treatment with AF-SWCNTs resulted in a marked reduction in S-phase of the cell cycle. In a previously standardized system to study BCG antigen presentation by PLE cells and PMs to sensitized T helper cells, AF-SWCNTs could significantly lower the antigen presentation ability of both cell types. These results show that mouse primary lung epithelial cells can efficiently internalize AF-SWCNTs and the uptake of nanotubes interfered with biological functions of PLE cells including their ability to present BCG antigens to sensitized T helper cells.

  17. Modeling and analysis of early events in T-lymphocyte antigen-activated intracellular-signaling pathways

    Zheng, Yanan; Balakrishnan, Venkataramanan; Buzzard, Greg; Geahlen, Robert; Harrison, Marietta; Rundell, Ann

    2005-12-01

    The T-cell antigen-activated signaling pathway is a highly regulated intracellular biochemical system that is crucial for initiating an appropriate adaptive immune response. To improve the understanding of the complex regulatory mechanisms controlling the early events in T-cell signaling, a detailed mathematical model was developed that utilizes ordinary differential equations to describe chemical reactions of the signaling pathway. The model parameter values were constrained by experimental data on the activation of a specific signaling intermediate and indicated an initial rapid cascade of phosphorylation events followed by a comparatively slow signal downregulation. Nonlinear analysis of the model suggested that thresholding and bistability occur as a result of the embedded positive and negative feedback loops within the model. These nonlinear system properties may enhance the T-cell receptor specificity and provide sub-threshold noise filtering with switch-like behavior to ensure proper cell response. Additional analysis using a reduced second-order model led to further understanding of the observed system behavior. Moreover, the interactions between the positive and negative feedback loops enabled the model to exhibit, among a variety of other feasible dynamics, a sustained oscillation that corresponds to a stable limit cycle in the two-dimensional phase plane. Quantitative analysis in this paper has helped identify potential regulatory mechanisms in the early T-cell signaling events. This integrated approach provides a framework to quantify and discover the ensemble of interconnected T-cell antigen-activated signaling pathways from limited experimental data.

  18. Cytochemical localization of ATP diphosphohydrolase from Leishmania (Viannia) braziliensis promastigotes and identification of an antigenic and catalytically active isoform.

    Rezende-Soares, F A; Carvalho-Campos, C; Marques, M J; Porcino, G N; Giarola, N L L; Costa, B L S; Taunay-Rodrigues, A; Faria-Pinto, P; Souza, M A; Diniz, V A; Corte-Real, S; Juliano, M A; Juliano, L; Vasconcelos, E G

    2010-04-01

    An ATP diphosphohydrolase (EC 3.6.1.5) activity was identified in a Leishmania (Viannia) braziliensis promastigotes preparation (Lb). Ultrastructural cytochemical microscopy showed this protein on the parasite surface and also stained a possible similar protein at the mitochondrial membrane. Isolation of an active ATP diphosphohydrolase isoform from Lb was obtained by cross-immunoreactivity with polyclonal anti-potato apyrase antibodies. These antibodies, immobilized on Protein A-Sepharose, immunoprecipitated a polypeptide of approximately 48 kDa and, in lower amount, a polypeptide of approximately 43 kDa, and depleted 83% ATPase and 87% of the ADPase activities from detergent-homogenized Lb. Potato apyrase was recognized in Western blots by IgG antibody from American cutaneous leishmaniasis (ACL) patients, suggesting that the parasite and vegetable proteins share antigenic conserved epitopes. Significant IgG seropositivity in serum samples diluted 1:50 from ACL patients (n=20) for Lb (65%) and potato apyrase (90%) was observed by ELISA technique. Significant IgG antibody reactivity was also observed against synthetic peptides belonging to a conserved domain from L. braziliensis NDPase (80% seropositivity) and its potato apyrase counterpart (50% seropositivity), in accordance with the existence of shared antigenic epitopes and demonstrating that in leishmaniasis infection the domain r82-103 from L. braziliensis NDPase is a target for the human immune response. PMID:19961654

  19. Tumorigenic activity of Merkel cell polyomavirus T antigens expressed in the stratified epithelium of mice

    Spurgeon, Megan E.; Cheng, Jingwei; Bronson, Roderick T.; Lambert, Paul F.; DeCaprio, James A.

    2015-01-01

    Merkel cell polyomavirus (MCPyV) is frequently associated with Merkel cell carcinoma (MCC), a highly aggressive neuroendocrine skin cancer. Most MCC tumors contain integrated copies of the viral genome with persistent expression of the MCPyV large T (LT) and small T (ST) antigen. MCPyV isolated from MCC typically contain wild type ST but truncated forms of LT that retain the N-terminus but delete the C-terminus and render LT incapable of supporting virus replication. To determine the oncogeni...

  20. Engineering a prostate-specific membrane antigen-activated tumor endothelial cell prodrug for cancer therapy

    Denmeade, Samuel R; Mhaka, Annastasiah M; Rosen, D Marc;

    2012-01-01

    Heterogeneous expression of drug target proteins within tumor sites is a major mechanism of resistance to anticancer therapies. We describe a strategy to selectively inhibit, within tumor sites, the function of a critical intracellular protein, the sarcoplasmic/endoplasmic reticulum calcium...... adenosine triphosphatase (SERCA) pump, whose proper function is required by all cell types for viability. To achieve targeted inhibition, we took advantage of the unique expression of the carboxypeptidase prostate-specific membrane antigen (PSMA) by tumor endothelial cells within the microenvironment of...

  1. Anti-allergic activity of R-phycocyanin from Porphyra haitanensis in antigen-sensitized mice and mast cells.

    Liu, Qingmei; Wang, Youzhao; Cao, Minjie; Pan, Tzuming; Yang, Yang; Mao, Haiyan; Sun, Lechang; Liu, Guangming

    2015-04-01

    The prevalence of food allergy has increased in Asian countries. Marine algae have been proposed as the potential resource for anti-allergic therapeutics. The present study was aimed at isolating R-phycocyanin (RPC) from Porphyra haitanensis and determining the anti-allergy potential of RPC in antigen-sensitized mice and mast cells. In animal experiments, RPC could effectively reduce tropomyosin (TM)-specific immunoglobulin E (IgE) and histamine levels, alleviate allergy symptoms and jejunum tissue inflammation in mice, and inhibit the expression and release of cytokines (interleukin-4 (IL-4) and IL-13) in peritoneal lavage fluid. In spleen lymphocyte experiments, high purity of RPC skewed the immunological function of CD4(+) T cells towards Th1 activity. A higher expression of interferon (IFN)-γ was induced by a synergistic effect of TM and RPC. Through the Jun N-terminal kinase and Janus kinase 2 signaling pathways, IFN-γ synthesis was induced by RPC in combination with TM. Anti-allergic effect of RPC was evaluated in IgE-mediated rat mast RBL-2H3 cells. The results demonstrated that RPC inhibited allergy markers, including the release of β-hexosaminidase, histamine and ROS in antigen-sensitized RBL-2H3 cells. RPC also suppressed the production of pro-inflammatory factors (IL-4 and tumor necrosis factor-α). In conclusion, RPC decreased allergic sensitization against TM by blocking Th2 cell polarization as well as suppressed the release of allergic-mediators in antigen-stimulated mast cells. It may be used as a functional food component or active pharmaceutical ingredient for allergic patients. PMID:25746371

  2. Epstein-Barr virus nuclear antigen 3C targets p53 and modulates its transcriptional and apoptotic activities

    The p53 tumor suppressor gene is one of the most commonly mutated genes in human cancers and the corresponding encoded protein induces apoptosis or cell-cycle arrest at the G1/S checkpoint in response to DNA damage. To date, previous studies have shown that antigens encoded by human tumor viruses such as SV40 large T antigen, adenovirus E1A and HPV E6 interact with p53 and disrupt its functional activity. In a similar fashion, we now show that EBNA3C, one of the EBV latent antigens essential for the B-cell immortalization in vitro, interacts directly with p53. Additionally, we mapped the interaction of EBNA3C with p53 to the C-terminal DNA-binding and the tetramerization domain of p53, and the region of EBNA3C responsible for binding to p53 was mapped to the N-terminal domain of EBNA3C (residues 130-190), previously shown to interact with a number of important cell-cycle components, specifically SCFSkp2, cyclin A, and cMyc. Furthermore, we demonstrate that EBNA3C substantially represses the transcriptional activity of p53 in luciferase based reporter assays, and rescues apoptosis induced by ectopic p53 expression in SAOS-2 (p53-/-) cells. Interestingly, we also show that the DNA-binding ability of p53 is diminished in the presence of EBNA3C. Thus, the interaction between the p53 and EBNA3C provides new insights into the mechanism(s) by which the EBNA3C oncoprotein can alter cellular gene expression in EBV associated human cancers.

  3. Exosomes Derived from M. Bovis BCG Infected Macrophages Activate Antigen-Specific CD4+ and CD8+ T Cells In Vitro and In Vivo

    Giri, Pramod K.; Schorey, Jeffrey S.

    2008-01-01

    Activation of both CD4(+) and CD8(+) T cells is required for an effective immune response to an M. tuberculosis infection. However, infected macrophages are poor antigen presenting cells and may be spatially separated from recruited T cells, thus limiting antigen presentation within a granuloma. Our previous studies showed that infected macrophages release from cells small membrane-bound vesicles called exosomes which contain mycobacterial lipid components and showed that these exosomes could...

  4. IFN-gamma and prostaglandin E2 inhibit IL-4-induced expression of Fc epsilon R2/CD23 on B lymphocytes through different mechanisms without altering binding of IL-4 to its receptor

    Galizzi, J.P.; Cabrillat, H.; Rousset, F.; Menetrier, C.; de Vries, J.E.; Banchereau, J.

    1988-09-15

    Human rIL-4 specifically induces the expression of the low affinity receptor for IgE (Fc epsilon R2/CD23) on normal B cells and on the Burkitt lymphoma cell line Jijoye. IL-4 does not induce the generation of the second messenger cAMP in Jijoye cells. PGE2 (at 10(-7) M) was found to inhibit by 50% the IL-4 mediated Fc epsilon R2/CD23 induction on Jijoye cells. The PGE2 half maximum inhibitory concentration (1 nM) was comparable to that inducing a half maximal increase of intracellular cAMP (4nM PGE2). 8-bromo-cAMP (10(-3) M), forskolin (10(-5) M), and cholera toxin (100 ng/ml), which increase intracellular cAMP levels, also inhibited by 40 to 80% the IL-4 induced Fc epsilon R2/CD23 expression on Jijoye cells. PGE2 8-bromo-cAMP, forskolin, and cholera toxin also inhibited the IL-4-induced Fc epsilon R2/CD23 expression on normal B lymphocytes. Taken together these data suggest that PGE2 inhibits the IL-4 induced Fc epsilon R2/CD23 through an increase of intracellular cAMP. In contrast, IFN-gamma, which strongly inhibits IL-4-mediated Fc epsilon R2/CD23 expression on Jijoye cells, did not increase intracellular cAMP levels and thus probably acts through another mechanism. IFN-gamma and PGE2 did not inhibit binding of IL-4 to its receptor. It could be excluded that IFN-gamma and PGE2 were acting via an alteration/desensitization of the IL-4R inasmuch as 24 h pre-incubation of Jijoye cells with these agents affected neither the affinity of 125I-IL-4 for its receptor (Kd = 0.8 to 1.5 x 10(-10) M) nor the maximal number of binding sites per Jijoye cells (Bmax = 390 to 550). Furthermore, IFN-gamma and PGE2 did not affect the internalization and degradation of 125I-IL-4. These data demonstrate that PGE2 and IFN-gamma inhibit the IL-4-mediated induction of Fc epsilon R2/CD23 on B lymphocytes via different mechanisms that do not alter the interaction of IL-4 with its receptor.

  5. Expression of costimulatory molecules in antigen-activated peritoneal macrophages treated with either ovalbumin or palmitoyl-ova conjugates

    Flávia Márcia Oliveira

    2013-12-01

    Full Text Available One of the mechanisms by which adjuvants are believed to promote T-cell activation and prevent induction of oral tolerance is by up-regulating the expression of co-stimulatory molecules on antigen presenting cells. Mice treated orally with palmitoyl-ovalbumin conjugates become immunized, while those treated with native ovalbumin (Ova become tolerant. Cells from the peritoneal cavity of B6D2F1 mice were cultured in the presence of 0.01, or 0.1 mg/100ml of either Ova, or palmitoyl-Ova and tested for the presence of cell markers. PE-conjugated anti-mouse CD80, CD86, and CD11b antibodies as well as biotin-PE were used to stain the antigen-activated peritoneal cells. A significant increase in the expression of CD86 and CD80 was observed following in vitro stimulation with palmitoyl-Ova; additionally, both Ova and palmitoyl-Ova induced the basal expression of CD11b. These findings could be related with the strong T-cell proliferative response induced by palmitoyl-Ova.

  6. Dectin-2 Recognizes Mannosylated O-antigens of Human Opportunistic Pathogens and Augments Lipopolysaccharide Activation of Myeloid Cells.

    Wittmann, Alexandra; Lamprinaki, Dimitra; Bowles, Kristian M; Katzenellenbogen, Ewa; Knirel, Yuriy A; Whitfield, Chris; Nishimura, Takashi; Matsumoto, Naoki; Yamamoto, Kazuo; Iwakura, Yoichiro; Saijo, Shinobu; Kawasaki, Norihito

    2016-08-19

    LPS consists of a relatively conserved region of lipid A and core oligosaccharide and a highly variable region of O-antigen polysaccharide. Whereas lipid A is known to bind to the Toll-like receptor 4 (TLR4)-myeloid differentiation factor 2 (MD2) complex, the role of the O-antigen remains unclear. Here we report a novel molecular interaction between dendritic cell-associated C-type lectin-2 (Dectin-2) and mannosylated O-antigen found in a human opportunistic pathogen, Hafnia alvei PCM 1223, which has a repeating unit of [-Man-α1,3-Man-α1,2-Man-α1,2-Man-α1,2-Man-α1,3-]. H. alvei LPS induced higher levels of TNFα and IL-10 from mouse bone marrow-derived dendritic cells (BM-DCs), when compared with Salmonella enterica O66 LPS, which has a repeat of [-Gal-α1,6-Gal-α1,4-[Glc-β1,3]GalNAc-α1,3-GalNAc-β1,3-]. In a cell-based reporter assay, Dectin-2 was shown to recognize H. alvei LPS. This binding was inhibited by mannosidase treatment of H. alvei LPS and by mutations in the carbohydrate-binding domain of Dectin-2, demonstrating that H. alvei LPS is a novel glycan ligand of Dectin-2. The enhanced cytokine production by H. alvei LPS was Dectin-2-dependent, because Dectin-2 knock-out BM-DCs failed to do so. This receptor cross-talk between Dectin-2 and TLR4 involved events including spleen tyrosine kinase (Syk) activation and receptor juxtaposition. Furthermore, another mannosylated LPS from Escherichia coli O9a also bound to Dectin-2 and augmented TLR4 activation of BM-DCs. Taken together, these data indicate that mannosylated O-antigens from several Gram-negative bacteria augment TLR4 responses through interaction with Dectin-2. PMID:27358401

  7. Protective Profile Involving CD23/IgE-mediated NO Release is a Hallmark of Cutaneous Leishmaniasis Patients from the Xakriabá Indigenous Community in Minas Gerais, Brazil.

    Carvalho-Gontijo, R; Peruhype-Magalhães, V; Costa-Silva, M F; Martins-Filho, O A; Quaresma, P F; Freire, J de Moura; Moreno, E de Castro; Teixeira-Carvalho, A; Gontijo, C M Ferreira

    2015-06-01

    In this study, we described, for the first time, specific aspects of an anti-Leishmania immune response in a Brazilian Xakriabá indigenous community. Induction of an intracellular NO pathway, triggered by the binding of IgE to CD23 receptor in IFN-γ/IL-4 cytokines environment, was evaluated in localized cutaneous leishmaniasis (LCL) carriers and positive Montenegro skin test (MST) individuals without skin lesion (MT(+) SL(-)). Our data demonstrated that the higher frequency of CD23(+) CD14(+) monocytes and the increased serum levels of IgE observed in the LCL group were even higher in LCL carriers with late lesions (LCL≥60). Furthermore, patients with LCL presented increased NO production after Leishmania (Viannia) braziliensis stimulation and this NO profile was independent of the time of the lesion (recent LCL<60 or late LCL≥60). We also showed that the increased frequency of IFN-γ(+) and IL-4(+) CD4(+) T cells is related to the MT(+) SL(-) group. The results of biomarker signature curves demonstrated that in the MT(+) SL(-) group, the index signature was characterized by DAF-2T(+) CD14(+)/IL-4(+) CD8(+)/IFN-γ(+) CD4(+)/IL-4(+) CD4(+). On the other hand, the LCL group presented a higher index of DAF-2T(+) CD14(+)/CD23(+) CD14(+)/IL-4(+) CD8(+), associated with a lower index of IFN-γ(+) CD8(+). Considering the time of lesion, data analysis demonstrated that the main differences observed were highlighted in LCL<60 patients, with a higher index of CD23(+) CD14(+), which was also present in LCL≥60 patients. In conclusion, our data suggest that the protective immune response involving CD23-IgE-mediated NO release is a hallmark of patients with LCL. However, in MT(+) SL(-) individuals, another different leishmanicidal mechanism seems to be involved. PMID:25802003

  8. A novel strategy to improve antigen presentation for active immunotherapy in cancer. Fusion of the human papillomavirus type 16 E7 antigen to a cell penetrating peptide

    Facilitating the delivery of exogenous antigens to antigen-presenting cells, ensuing processing and presentation via the major histocompatibility complex class I and induction of an effective immune response are fundamental for an effective therapeutic cancer vaccine. In this regard, we propose the use of cell-penetrating peptides fused to a tumor antigen. To demonstrate this concept we designed a fusion protein comprising a novel cell-penetrating and immunostimulatory peptide corresponding to residues 32 to 51 of the Limulus anti-lipopolysaccharide factor protein (LALF32-51) linked to human papillomavirus 16 E7 antigen (LALF32-51-E7). In this work, we demonstrated that the immunization with LALF32-51-E7 using the TC-1 mouse model induces a potent and long-lasting anti-tumor response supported on an effective E7-specific CD8+T-cell response. The finding that therapeutic immunization with LALF32-51 or E7 alone, or an admixture of LALF32-51 and E7, does not induce significant tumor reduction indicates that covalent linkage between LALF32-51 and E7 is required for the anti-tumor effect. These results support the use of this novel cell-penetrating peptide as an efficient means for delivering therapeutic targets into cellular compartments with the induction of a cytotoxic CD8+T lymphocyte immune response. This approach is promissory for the treatment of tumors associated with the human papillomavirus 16, which is responsible for the 50% of cervical cancer cases worldwide and other malignancies. Furthermore, protein-based vaccines can circumvent the major histocompatibility complex specificity limitation associated with peptide vaccines providing a greater extent in their application

  9. Paracoccidioides lutzii Plp43 is an active glucanase with partial antigenic identity with P. brasiliensis gp43.

    Natanael P Leitão

    2014-08-01

    Full Text Available Paracoccidioides brasiliensis and P. lutzii cause paracoccidioidomycosis (PCM. P. brasiliensis main diagnostic antigen is glycoprotein gp43, and its peptide sequence is 81% identical with a P. lutzii ortholog here called Plp43. P. lutzii ("Pb01-like" apparently predominates in Midwestern/Northern Brazil, where high percentages of false-negative reactions using P. brasiliensis antigens have recently been reported. The aim of this work was to produce recombinant Plp43 to study its antigenic identity with gp43.We expressed rPlp43 as a secreted major component in Pichia pastoris and studied its reactivity in immunoblot with PCM patients' sera from Southwestern and Midwestern Brazil.We showed that rPlp43 is not glycosylated and bears glucanase activity. The protein did not react with anti-gp43 monoclonal antibodies in immunoblot, suggesting absence of the corresponding gp43 epitopes. Nevertheless, common epitope(s might exist, considering that gp43-positive PCM sera recognized rPlp43 in immunoblot, while gp43-negative sera (33 out of 51 from patients resident in Midwestern Brazil were also rPlp43-negative. Two genotyped P. lutzii were from patients with gp43-negative sera, suggesting that non-reactive sera are from patients infected with this species.Our data suggest that gp43 and Plp43 bear one or only a few common epitopes and that gp43 cannot be used in diagnosis of PCM patients infected with P. lutzii probably because Plp43 is poorly expressed during infection.

  10. Different-Sized Gold Nanoparticle Activator/Antigen Increases Dendritic Cells Accumulation in Liver-Draining Lymph Nodes and CD8+ T Cell Responses.

    Zhou, Qianqian; Zhang, Yulong; Du, Juan; Li, Yuan; Zhou, Yong; Fu, Qiuxia; Zhang, Jingang; Wang, Xiaohui; Zhan, Linsheng

    2016-02-23

    The lack of efficient antigen and activator delivery systems, as well as the restricted migration of dendritic cells (DCs) to secondary lymph organs, dramatically limits DC-based adoptive immunotherapy. We selected two spherical gold nanoparticle (AuNP)-based vehicles of optimal size for activator and antigen delivery. Their combination (termed the NanoAu-Cocktail) was associated with the dual targeting of CpG oligonucleotides (CpG-ODNs) and an OVA peptide (OVAp) to DC subcellular compartments, inducing enhanced antigen cross-presentation, upregulated expression of costimulatory molecules and elevated secretion of T helper1 cytokines. We demonstrated that the intravenously transfused NanoAu-Cocktail pulsed DCs showed dramatically improved in vivo homing ability to lymphoid tissues and were settled in T cell area. Especially, by tissue-distribution analysis, we found that more than 60% of lymphoid tissues-homing DCs accumulated in liver-draining lymph nodes (LLNs). The improved homing ability of NanoAu-Cocktail pulsed DCs was associated with the high expression of chemokine receptor 7 (CCR7) and rearrangement of the cytoskeletons. In addition, by antigen-specific tetramers detection, NanoAu-Cocktail pulsed DCs were proved able to elicit strong antigen-specific CD8+ T cell responses, which provided enhanced protection from viral invasions. This study highlights the importance of codelivering antigen/adjuvant using different sized gold nanoparticles to improve DC homing and therapy. PMID:26771692

  11. Expression of Major Antigen Domains of Gene of E2 CSFV and Analysis of its Immunological Activity

    Hong TIAN; Xiang-tao LIU; Jing-yan WU; You-jun SHANG; Tao JIANG; Hai-xue ZHENG; Qing-ge XIE

    2008-01-01

    E2 is an envelope glycoprotein of Classical swine fever virus (CSFV) and contains sequential neutralizing epitopes to induce virus-neutralizing antibodies and mount protective immunity in the natural host. In this study, four antigen domains (ABCD) of the E2 gene was cloned from CSFV Shimen strain into the retroviral vector pBABE puro and expressed in eukaryotic cell (PK15) by an retroviral gene expression system, and the activity of recombinant E2 protein to induce immune responses was evaluated in rabbits. The results indicated that recombinant E2 protein can be recognized by fluorescence antibodies of CSFV and CSFV positive serum (Lanzhou Veterinary Research Institute, Chinese Academy of Agricultural Sciences, Lanzhou, China) using Western blot, indirect immunofluorescence antibody test (IFAT) and ELISA, Furthermore, anti-CSFV specific antibodies and lymphocyte proliferation were elicited and increased by recombinant protein after vaccination. In the challenge test, all of rabbits vaccinated with recombinant protein and Chinese vaccine strain (C-strain) were fully protected from a rabbit spleen virus challenge. These results indicated that a retroviral-based epitope-vaccine carrying the major antigen domains of E2 is able to induce high level of epitope-specific antibodies and exhibits similar protective capability with that induced by the C-strain, and encourages further work towards the development of a vaccine against CSFV infection.

  12. Expression of the K54 and O4 specific antigen has opposite effects on the bactericidal activity of squalamine against an extraintestinal isolate of Escherichia coli.

    Russo, T A; Mylotte, D

    1998-05-15

    Squalamine is a novel cationic steroid that possesses potent, broad spectrum, antimicrobial activity. Recent data suggests that squalamine or related compounds may be present and important in host resistance to infection in the urinary tract. Therefore, the role of the K54 capsule and the O4 specific antigen moiety of the lipopolysaccharide in protecting an extraintestinal isolate of Escherichia coli against the bactericidal activity of this novel antimicrobial compound was studied. The O4 specific antigen was important for protection against squalamine. Surprisingly, in contrast, the presence of the K54 antigen enhanced the bactericidal activity of squalamine. This is the first example, to our knowledge, in which an established virulence trait, the K54 capsule, may be detrimental to an infecting pathogen under certain circumstances. PMID:9627966

  13. The Fab fragment of a directly activating monoclonal antibody that precipitates a disulfide-linked heterodimer from a helper T cell clone blocks activation by either allogeneic Ia or antigen and self-Ia

    1984-01-01

    We characterize a monoclonal antibody directed against the antigen/Ia receptor of a cloned helper T cell line that induced T cell clone proliferation and T cell clone-dependent B cell proliferation at antibody concentrations as low as 10(-11) M. A Fab fragment of this antibody was not stimulatory, implicating cross-linking of antigen receptors as the primary signal for T cell activation. The Fab fragment inhibited activation of this clone by both allogeneic Ia and antigen plus self-Ia, but no...

  14. Treponema pallidum (syphilis) antigen TpF1 induces angiogenesis through the activation of the IL-8 pathway.

    Pozzobon, Tommaso; Facchinello, Nicola; Bossi, Fleur; Capitani, Nagaja; Benagiano, Marisa; Di Benedetto, Giulietta; Zennaro, Cristina; West, Nicole; Codolo, Gaia; Bernardini, Marialina; Baldari, Cosima Tatiana; D'Elios, Mario Milco; Pellegrini, Luca; Argenton, Francesco; de Bernard, Marina

    2016-01-01

    Over 10 million people every year become infected by Treponema pallidum and develop syphilis, a disease with broad symptomatology that, due to the difficulty to eradicate the pathogen from the highly vascularized secondary sites of infection, is still treated with injections of penicillin. Unlike most other bacterial pathogens, T. pallidum infection produces indeed a strong angiogenic response whose mechanism of activation, however, remains unknown. Here, we report that one of the major antigen of T. pallidum, the TpF1 protein, has growth factor-like activity on primary cultures of human endothelial cells and activates specific T cells able to promote tissue factor production. The growth factor-like activity is mediated by the secretion of IL-8 but not of VEGF, two known angiogenic factors. The pathogen's factor signals IL-8 secretion through the activation of the CREB/NF-κB signalling pathway. These findings are recapitulated in an animal model, zebrafish, where we observed that TpF1 injection stimulates angiogenesis and IL-8, but not VEGF, secretion. This study suggests that the angiogenic response observed during secondary syphilis is triggered by TpF1 and that pharmacological therapies directed to inhibit IL-8 response in patients should be explored to treat this disease. PMID:26728351

  15. Exosomes derived from M. Bovis BCG infected macrophages activate antigen-specific CD4+ and CD8+ T cells in vitro and in vivo.

    Pramod K Giri

    Full Text Available Activation of both CD4(+ and CD8(+ T cells is required for an effective immune response to an M. tuberculosis infection. However, infected macrophages are poor antigen presenting cells and may be spatially separated from recruited T cells, thus limiting antigen presentation within a granuloma. Our previous studies showed that infected macrophages release from cells small membrane-bound vesicles called exosomes which contain mycobacterial lipid components and showed that these exosomes could stimulate a pro-inflammatory response in naïve macrophages. In the present study we demonstrate that exosomes stimulate both CD4(+ and CD8(+ splenic T cells isolated from mycobacteria-sensitized mice. Although the exosomes contain MHC I and II as well as costimulatory molecules, maximum stimulation of T cells required prior incubation of exosomes with antigen presenting cells. Exosomes isolated from M. bovis and M. tuberculosis infected macrophages also stimulated activation and maturation of mouse bone marrow-derived dendritic cells. Interestingly, intranasal administration of mice with exosomes isolated from M. bovis BCG infected macrophages induce the generation of memory CD4(+ and CD8(+ T cells. The isolated T cells also produced IFN-gamma upon restimulation with BCG antigens. The release of exosomes from infected macrophages may overcome some of the defects in antigen presentation associated with mycobacterial infections and we suggest that exosomes may be a promising M. tuberculosis vaccine candidate.

  16. Interaction between M-CSF and IL-10 on productions of IL-12 and IL-18 and expressions of CD14, CD23, and CD64 by human monocytes

    Xiao-hui JI; Ting YAO; Jun-chuan QIN; Shu-kui WANG; Hui-juan WANG; Kun YAO

    2004-01-01

    AIM: To Study the interaction of macrophage colony-stimulating factor (M-CSF) and interleukin-10 (IL-10) in productions of IL-12 and IL-18 and expressions of CD14, CD23, and CD64 by human monocytes. METHODS:Purified adherent human monocytes were cultured with M-CSF or IL-10 alone, or with M-CSF+IL-10 and 2-3d later, the culture supernatants and cells were separated and collected. IL-12P40 and IL-18 levels in the supernatants were determined by ELISA and the percentages of CD14, CD23, and CD64 positive cells were examined by flow cytometry. RESULTS: (1) IL-10 decreased M-CSF-induced IL-18 levels, while M-CSF further reduced IL-12P40 level in the culture supernatants of IL-10-treated monocytes; (2) IL-10 alone had no effect on the percentage of CD14-positive cells, but further increased the percentage of CD14-positive cells induced by M-CSF; M-CSF alone had no effect on the percentage of CD64-positive cells, but further increased the percentage of CD64-positive cells induced by IL-10; (3) IL-10 decreased the percentage of CD23-positive cells induced by M-CSF.CONCLUSION: Between M-CSF and IL-10, there were antagonistic effects on inducing IL-18 and CD23 expressions by monocytes; there were also synergistic effects on inhibiting IL-12P40 production and inducing CD 14 and CD64 expressions by monocytes.

  17. Active immunization with an octa-valent Staphylococcus aureus antigen mixture in models of S. aureus bacteremia and skin infection in mice.

    Sanne van den Berg

    Full Text Available Proteomic studies with different Staphylococcus aureus isolates have shown that the cell surface-exposed and secreted proteins IsaA, LytM, Nuc, the propeptide of Atl (pro-Atl and four phenol-soluble modulins α (PSMα are invariantly produced by this pathogen. Therefore the present study was aimed at investigating whether these proteins can be used for active immunization against S. aureus infection in mouse models of bacteremia and skin infection. To this end, recombinant His-tagged fusions of IsaA, LytM, Nuc and pro-Atl were isolated from Lactococcus lactis or Escherichia coli, while the PSMα1-4 peptides were chemically synthesized. Importantly, patients colonized by S. aureus showed significant immunoglobulin G (IgG responses against all eight antigens. BALB/cBYJ mice were immunized subcutaneously with a mixture of the antigens at day one (5 μg each, and boosted twice (25 μg of each antigen with 28 days interval. This resulted in high IgG responses against all antigens although the response against pro-Atl was around one log lower compared to the other antigens. Compared to placebo-immunized mice, immunization with the octa-valent antigen mixture did not reduce the S. aureus isolate P load in blood, lungs, spleen, liver, and kidneys in a bacteremia model in which the animals were challenged for 14 days with a primary load of 3 × 10(5 CFU. Discomfort scores and animal survival rates over 14 days did not differ between immunized mice and placebo-immunized mice upon bacteremia with S. aureus USA300 (6 × 10(5 CFU. In addition, this immunization did not reduce the S. aureus isolate P load in mice with skin infection. These results show that the target antigens are immunogenic in both humans and mice, but in the used animal models do not result in protection against S. aureus infection.

  18. Structural Insights into the Protease-like Antigen Plasmodium falciparum SERA5 and Its Noncanonical Active-Site Serine

    Hodder, Anthony N.; Malby, Robyn L.; Clarke, Oliver B.; Fairlie, W. Douglas; Colman, Peter M.; Crabb, Brendan S.; Smith, Brian J.; (WEHIMR); (Melbourne)

    2009-08-28

    The sera genes of the malaria-causing parasite Plasmodium encode a family of unique proteins that are maximally expressed at the time of egress of parasites from infected red blood cells. These multi-domain proteins are unique, containing a central papain-like cysteine-protease fragment enclosed between the disulfide-linked N- and C-terminal domains. However, the central fragment of several members of this family, including serine repeat antigen 5 (SERA5), contains a serine (S596) in place of the active-site cysteine. Here we report the crystal structure of the central protease-like domain of Plasmodium falciparum SERA5, revealing a number of anomalies in addition to the putative nucleophilic serine: (1) the structure of the putative active site is not conducive to binding substrate in the canonical cysteine-protease manner; (2) the side chain of D594 restricts access of substrate to the putative active site; and (3) the S{sub 2} specificity pocket is occupied by the side chain of Y735, reducing this site to a small depression on the protein surface. Attempts to determine the structure in complex with known inhibitors were not successful. Thus, despite having revealed its structure, the function of the catalytic domain of SERA5 remains an enigma.

  19. GD2-specific CAR T Cells Undergo Potent Activation and Deletion Following Antigen Encounter but can be Protected From Activation-induced Cell Death by PD-1 Blockade.

    Gargett, Tessa; Yu, Wenbo; Dotti, Gianpietro; Yvon, Eric S; Christo, Susan N; Hayball, John D; Lewis, Ian D; Brenner, Malcolm K; Brown, Michael P

    2016-06-01

    Chimeric antigen receptor (CAR) T cells have shown great promise in the treatment of hematologic malignancies but more variable results in the treatment of solid tumors and the persistence and expansion of CAR T cells within patients has been identified as a key correlate of antitumor efficacy. Lack of immunological "space", functional exhaustion, and deletion have all been proposed as mechanisms that hamper CAR T-cell persistence. Here we describe the events following activation of third-generation CAR T cells specific for GD2. CAR T cells had highly potent immediate effector functions without evidence of functional exhaustion in vitro, although reduced cytokine production reversible by PD-1 blockade was observed after longer-term culture. Significant activation-induced cell death (AICD) of CAR T cells was observed after repeated antigen stimulation, and PD-1 blockade enhanced both CAR T-cell survival and promoted killing of PD-L1(+) tumor cell lines. Finally, we assessed CAR T-cell persistence in patients enrolled in the CARPETS phase 1 clinical trial of GD2-specific CAR T cells in the treatment of metastatic melanoma. Together, these data suggest that deletion also occurs in vivo and that PD-1-targeted combination therapy approaches may be useful to augment CAR T-cell efficacy and persistence in patients. PMID:27019998

  20. Prospective evaluation of a whole-blood test using Mycobacterium tuberculosis-specific antigens ESAT-6 and CFP-10 for diagnosis of active tuberculosis

    Ravn, Pernille; Munk, Martin E; Andersen, Ase B; Lundgren, Bettina; Lundgren, Jens Dilling; Nielsen, Lars Nørregaard; Kok-Jensen, Axel; Andersen, Peter; Weldingh, Karin

    2005-01-01

    A new immunodiagnostic test based on the Mycobacterium tuberculosis-specific antigens CFP-10/ESAT-6(QFT-RD1) has been launched as an aid in the diagnosis of latent tuberculosis (TB) infection (LTBI). The aim of this study was to evaluate this test for the diagnosis of active TB. Eighty-two patients...

  1. In vitro cytotoxic effects of CTL activated by dendritic cells loaded with esophageal cancer antigen peptide by 51Cr release assay

    Objective: RIT plays an important role in the targeted therapy for tumors. The aim of the paper was to study cytotoxic effects of the cytotoxic T lymphocytes (CTL) to human esophageal cancer cell line TE-1, activated by dendritic cells (DC) loaded with esophageal cancer antigen peptide. Methods: Esophageal cancer TE-1 cell antigen peptide was obtained by citrate phosphate buffer elution. DC were induced and proliferated in vitro and were loaded with the esophageal cancer antigen peptide. The tumor antigen specific CTL were generated from the DC. And the cytotoxicity of CTL to TE-1 was assessed by 51Cr release assay. Results: The killing rate of CTL activated by loaded DC[(81.12±2.93)%] was higher than that of CTL activated by DC unloaded [(11.16±3.07)%]. The killing rate of CTL activated by loaded DC in TE-1 pretreated with interferon (IFN)-γ [(89.15±3.62)%] was higher than that in cells without IFN-γ [(61.19±5.17)%]. The killing rate of CTL was higher than that in TE-1 with acid elution [(9.18±2.52)%]. The killing rate of CTL activated by loaded DC diminished in order in Eta-109, human adenocarcinoma cell line K59 and human suprarenal epithelioma cell line 786-0. Conclusions: Acid elution could get effective esophageal cancer antigen peptide from TE-1 cell membrane. The CTL activated by DC loaded with that peptide had specific cytotoxic effects to TE-1 cells. (authors)

  2. Wild-type, but not mutant, human p53 proteins inhibit the replication activities of simian virus 40 large tumor antigen.

    Friedman, P N; Kern, S. E.; Vogelstein, B; Prives, C

    1990-01-01

    Murine p53 blocks many of the replication activities of simian virus 40 (SV40) large tumor antigen (T antigen) in vitro. As murine cells do not replicate SV40 DNA, it was of interest to determine how p53 from permissive human cells functions. Recombinant baculoviruses encoding either the wild-type form of human p53 or a mutant p53 cloned from a human tumor cell line were constructed, and p53 proteins were purified from infected insect cells. Surprisingly, we found that wild-type human p53 was...

  3. Relationship between protein C antigen and anticoagulant activity during oral anticoagulation and in selected disease states.

    Vigano D'Angelo, S; Comp, P C; Esmon, C T; D'Angelo, A.

    1986-01-01

    Protein C is a natural vitamin K-dependent plasma anticoagulant, deficiencies of which have been found in patients with recurrent thrombosis and warfarin-induced skin necrosis. To appreciate more fully the role of protein C in disease states and during oral anticoagulation, a new functional assay for protein C involving adsorption of plasma protein C on a Ca+2-dependent monoclonal antibody, elution, quantitative activation, and assessment of plasma anticoagulant activity, has been developed. ...

  4. Non-major histocompatibility complex-restricted cytotoxic activity of blood mononuclear cells stimulated with secreted mycobacterial proteins and other mycobacterial antigens

    Ravn, P; Pedersen, B K

    1994-01-01

    Several observations indicate that non-major histocompatibility complex (MHC)-restricted cytotoxicity, mediated for example by natural killer cells and lymphokine-activated killer cells, may serve as an important antimicrobial defense mechanism. The purpose of the present study was to investigate...... the influences of different mycobacterial antigens on non-MHC-restricted cytotoxicity and further to investigate the ways by which various lymphocyte subpopulations contribute to the development of this cytotoxicity. Non-MHC-restricted cytotoxicity was induced following stimulation of mononuclear...... interferon. The CD4+ cells proliferated and expressed interleukin-2 receptors following stimulation with mycobacterial antigens.Depletion studies after antigen stimulation showed that the cytotoxic effector cells were CD16+ CD56+ and CD4-; the CD4+ cells alone did not mediate non-MHC-restricted cytotoxicity...

  5. Antigen smuggling in tuberculosis.

    Hudrisier, Denis; Neyrolles, Olivier

    2014-06-11

    The importance of CD4 T lymphocytes in immunity to M. tuberculosis is well established; however, how dendritic cells activate T cells in vivo remains obscure. In this issue of Cell Host & Microbe, Srivastava and Ernst (2014) report a mechanism of antigen transfer for efficient activation of antimycobacterial T cells. PMID:24922567

  6. Activated Complement Component 3 (C3) Is Required for Ultraviolet Induction of Immunosuppression and Antigenic Tolerance

    Hammerberg, Craig; Santosh K. Katiyar; Carroll, Michael C.; Cooper, Kevin D

    1998-01-01

    Complement component 3 (C3), a critical regulator of innate immunity, may also play a role in the regulation of cognate immunity, such as contact sensitivity responses. Because ultraviolet (UV) radiation also activates C3 in the skin, we determined whether the immunosuppressed state that results when a contact sensitizer is applied through UVB-exposed skin requires the presence and activation of C3. This question was addressed through the use of C3-deficient mice, blockade of C3 cleavage to C...

  7. B cells pulsed with Helicobacter pylori antigen efficiently activate memory CD8+ T cells from H. pylori-infected individuals.

    Azem, Josef; Svennerholm, Ann-Mari; Lundin, B Samuel

    2006-01-01

    Helicobacter pylori infection causes chronic gastritis that may progress to peptic ulcers or gastric adenocarcinoma and thereby cause major world-wide health problems. Previous studies have shown that CD4+ T cells are important in the immune response to H. pylori in humans, but the role of CD8+ T cells is less clear. In order to study the CD8+ T cell response to H. pylori in greater detail, we have evaluated efficient conditions for activation of CD8+ T cells in vitro. We show that H. pylori-reactive CD8+ T cells can be activated most efficiently by B cells or dendritic cells pulsed with H. pylori antigens. We further show that the majority of CD8+ T cells in H. pylori-infected gastric mucosa are memory cells, and that memory CD8+ T cells sorted from peripheral blood of H. pylori-infected individuals respond 15-fold more to H. pylori urease compared to memory cells from uninfected subjects. We conclude that CD8+ T cells do participate in the immune response to H. pylori, and this may have implications for the development of more severe disease outcomes in H. pylori-infected subjects. PMID:16324887

  8. A viral vectored prime-boost immunization regime targeting the malaria Pfs25 antigen induces transmission-blocking activity.

    Anna L Goodman

    Full Text Available The ookinete surface protein Pfs25 is a macrogamete-to-ookinete/ookinete stage antigen of Plasmodium falciparum, capable of exerting high-level anti-malarial transmission-blocking activity following immunization with recombinant protein-in-adjuvant formulations. Here, this antigen was expressed in recombinant chimpanzee adenovirus 63 (ChAd63, human adenovirus serotype 5 (AdHu5 and modified vaccinia virus Ankara (MVA viral vectored vaccines. Two immunizations were administered to mice in a heterologous prime-boost regime. Immunization of mice with AdHu5 Pfs25 at week 0 and MVA Pfs25 at week 10 (Ad-MVA Pfs25 resulted in high anti-Pfs25 IgG titers, consisting of predominantly isotypes IgG1 and IgG2a. A single priming immunization with ChAd63 Pfs25 was as effective as AdHu5 Pfs25 with respect to ELISA titers at 8 weeks post-immunization. Sera from Ad-MVA Pfs25 immunized mice inhibited the transmission of P. falciparum to the mosquito both ex vivo and in vivo. In a standard membrane-feeding assay using NF54 strain P. falciparum, oocyst intensity in Anopheles stephensi mosquitoes was significantly reduced in an IgG concentration-dependent manner when compared to control feeds (96% reduction of intensity, 78% reduction in prevalence at a 1 in 5 dilution of sera. In addition, an in vivo transmission-blocking effect was also demonstrated by direct feeding of immunized mice infected with Pfs25DR3, a chimeric P. berghei line expressing Pfs25 in place of endogenous Pbs25. In this assay the density of Pfs25DR3 oocysts was significantly reduced when mosquitoes were fed on vaccinated as compared to control mice (67% reduction of intensity, 28% reduction in prevalence and specific IgG titer correlated with efficacy. These data confirm the utility of the adenovirus-MVA vaccine platform for the induction of antibodies with transmission-blocking activity, and support the continued development of this alternative approach to transmission-blocking malaria subunit

  9. Partial in vitro analysis of toxic and antigenic activities of eleven Peruvian pitviper snake venoms.

    Guerra-Duarte, C; Lopes-Peixoto, J; Fonseca-de-Souza, B R; Stransky, S; Oliveira, D; Schneider, F S; Lopes-de-Souza, L; Bonilla, C; Silva, W; Tintaya, B; Yarleque, A; Chávez-Olórtegui, C

    2015-12-15

    This work used eleven Peruvian snake venoms (Bothrops andianus, Bothrops atrox, Bothrops barnetti, Bothrops castelnaudi, Bothriopsis chloromelas, Bothrocophias microphthalmus, Bothrops neuwiedi, Bothriopsis oligolepis, Bothriopsis peruviana, Bothrops pictus and Bothriopsis taeniata) to perform in vitro experimentation and determine its main characteristics. Hyaluronidase (HYAL), phospholipase A2 (PLA2), snake venom metalloproteinase (SVMP), snake venom serine protease (SVSP) and L-amino acid oxidase (LAAO) activities; toxicity by cell viability assays using MGSO3, VERO and HeLa cell lineages; and crossed immunoreactivity with Peruvian (PAV) and Brazilian (BAV) antibothropic polyvalent antivenoms, through ELISA and Western Blotting assays, were determined. Results show that the activities tested in this study were not similar amongst the venoms and each species present their own peculiarities, highlighting the diversity within Bothrops complex. All venoms were capable of reducing cell viability of all tested lineages. It was also demonstrated the crossed recognition of all tested venoms by both antivenoms. PMID:26365916

  10. Structural parameterization and functional prediction of antigenic polypeptome sequences with biological activity through quantitative sequence-activity models (QSAM) by molecular electronegativity edge-distance vector (VMED)

    LI; ZhiLiang; WU; ShiRong; CHEN; ZeCong; YE; Nancy; YANG; ShengXi; LIAO; ChunYang; ZHANG; MengJun; YANG; Li; MEI; Hu; YANG; Yan; ZHAO; Na; ZHOU; Yuan; ZHOU; Ping; XIONG; Qing; XU; Hong; LIU; ShuShen; LING; ZiHua; CHEN; Gang; LI; GenRong

    2007-01-01

    Only from the primary structures of peptides, a new set of descriptors called the molecular electronegativity edge-distance vector (VMED) was proposed and applied to describing and characterizing the molecular structures of oligopeptides and polypeptides, based on the electronegativity of each atom or electronic charge index (ECI) of atomic clusters and the bonding distance between atom-pairs. Here, the molecular structures of antigenic polypeptides were well expressed in order to propose the automated technique for the computerized identification of helper T lymphocyte (Th) epitopes. Furthermore, a modified MED vector was proposed from the primary structures of polypeptides, based on the ECI and the relative bonding distance of the fundamental skeleton groups. The side-chains of each amino acid were here treated as a pseudo-atom. The developed VMED was easy to calculate and able to work. Some quantitative model was established for 28 immunogenic or antigenic polypeptides (AGPP) with 14 (1―14) Ad and 14 other restricted activities assigned as "1"(+) and "0"(-), respectively. The latter comprised 6 Ab(15-20), 3 Ak(21-23), 2 Ek(24-26), 2 H-2k(27 and 28) restricted sequences. Good results were obtained with 90% correct classification (only 2 wrong ones for 20 training samples) and 100% correct prediction (none wrong for 8 testing samples); while contrastively 100% correct classification (none wrong for 20 training samples) and 88% correct classification (1 wrong for 8 testing samples). Both stochastic samplings and cross validations were performed to demonstrate good performance. The described method may also be suitable for estimation and prediction of classes I and II for major histocompatibility antigen (MHC) epitope of human. It will be useful in immune identification and recognition of proteins and genes and in the design and development of subunit vaccines. Several quantitative structure activity relationship (QSAR) models were developed for various

  11. Inhibition of Replication and Transcription Activator and Latency-Associated Nuclear Antigen of Kaposi’s Sarcoma-Associated Herpesvirus by Morpholino Oligomers

    Zhang, Yan-Jin; Wang, Kai-Yu; Stein, David A.; Patel, Deendayal; Watkins, Rheba; Moulton, Hong M.; Iversen, Patrick L.; Matson, David O.

    2006-01-01

    Kaposi’s sarcoma-associated herpesvirus (KSHV) is associated with Kaposi’s sarcoma and primary effusion lymphoma (PEL). The KSHV replication and transcription activator (RTA) and latency-associated nuclear antigen (LANA) play key roles in activating KSHV lytic replication and maintaining KSHV latency, respectively. Phosphorodiamidate morpholino oligomers (PMO) are similar to short single-stranded DNA oligomers, but possess a modified backbone that confers highly specific binding and resistanc...

  12. A Neoglycoconjugate Containing the Human Milk Sugar LNFPIII Drives Anti-Inflammatory Activation of Antigen Presenting Cells in a CD14 Dependent Pathway

    Tundup, Smanla; Srivastava, Leena; Norberg, Thomas; Watford, Wendy; Harn, Donald

    2015-01-01

    The milk pentasaccharide LNFPIII has therapeutic action for metabolic and autoimmune diseases and prolongs transplant survival in mice when presented as a neoglycoconjugate. Within LNFPIII is the Lewis(x) trisaccharide, expressed by many helminth parasites. In humans, LNFPIII is found in human milk and also known as stage-specific embryonic antigen-1. LNFPIII-NGC drives alternative activation of macrophages and dendritic cells via NF kappa B activation in a TLR4 dependent mechanism. However, ...

  13. Induction of antigen-specific TH 9 immunity accompanied by mast cell activation blocks tumor cell engraftment.

    Abdul-Wahid, Aws; Cydzik, Marzena; Prodeus, Aaron; Alwash, Mays; Stanojcic, Mile; Thompson, Megan; Huang, Eric H-B; Shively, John E; Gray-Owen, Scott D; Gariépy, Jean

    2016-08-15

    The engraftment of circulating cancer cells at distal sites represents a key step in the metastatic cascade, yet remains an unexplored target for therapeutic intervention. In this study, we establish that a vaccination strategy yielding an antigen-specific TH 9 response induces long term host surveillance and prevents the engraftment of circulating cancer cells. Specifically, we show that vaccination with a recombinant CEA IgV-like N domain, formulated with the TLR3 ligand poly I:C, elicits a CEA-specific TH 9 response, wherein IL-9 secreting TH cells act in concert with CEA N domain-specific antibodies as well as activated mast cells in preventing tumor cell engraftment. The development of this immune response was dependent on TLR3, since interference with the TLR3-dsRNA complex formation led to a reduction in vaccine-imparted protection and a shift in the resulting immune response toward a TH 2 response. These findings point to the existence of an alternate tumor targeting immune mechanism that can be exploited for the purpose of developing vaccine therapies targeting tumor dissemination and engraftment. PMID:27037842

  14. Characterization of a double-CRD-mutated Gal-8 recombinant protein that retains co-stimulatory activity on antigen-specific T-cell response.

    Schroeder, Matías Nicolás; Tribulatti, María Virginia; Carabelli, Julieta; André-Leroux, Gwenaëlle; Caramelo, Julio Javier; Cattaneo, Valentina; Campetella, Oscar

    2016-04-01

    Galectins (Gals) constitute a family of mammalian lectins with affinity for β-galactosides, characterized by the presence of conserved CRDs (carbohydrate-recognition domains). We have found previously that Gal-8, from the tandem-repeat group with two linked CRDs, exerts two separate actions on CD4(+)T-cells: antigen-independent proliferation and, at lower concentration, antigen-specific co-stimulation. Whereas proliferation can be ascribed to the pro-inflammatory role of Gal-8, the co-stimulatory activity of borderline T-cell-specific responses allows the proposal of Gal-8 as an adjuvant in vaccination. To study the relevance of glycan-lectin interaction to these T-cell activities, we generated a double-mutated protein (Gal-8mut) by replacing canonical arginine residues on each CRD, so as to abolish sugar-binding capacity. As expected, Gal-8mut was unable to bind to lactosyl-Sepharose, confirming that lactose recognition was precluded; however, preservation of lectin activity was still evident since Gal-8mut displayed haemoagglutinatory effects and binding capacity to the T-cell surface. To search for glycan affinity, a glycan microarray analysis was conducted which revealed that Gal-8mut lost most low- and intermediate-, but retained high-, affinity interactions, mainly to polylactosamines and blood group antigens. These findings were supported further by molecular modelling. Regarding biological activity, Gal-8mut was unable to induce T-cell proliferation, but efficiently co-stimulated antigen-specific responses, bothin vitroandin vivo.Therefore Gal-8mut represents a useful tool to dissect the specificities of lectin-glycan interactions underlying distinctive Gal-8 activities on T-cell biology. Moreover, given its distinguishing properties, Gal-8mut could be used to enhance borderline immune responses without the non-specific pro-inflammatory activity or other potential adverse effects. PMID:26795039

  15. Proliferating cell nuclear antigen (PCNA) activity in hepatocellular carcinoma, benign peri-neoplastic and normal liver.

    Mun, Kein-Seong; Cheah, Phaik-Leng; Baharudin, Nurul Bahiyah; Looi, Lai-Meng

    2006-12-01

    Hepatocellular carcinoma (HCC) is among the ten most common cancers in Malaysian males. As cellular proliferation is an important feature of malignant transformation, we studied the proliferation pattern of normal and benign perineoplastic liver versus hepatocellular carcinoma in an attempt to further understand the tumour transformation process. 39 HCC (21 with accompanying and 18 without cirrhosis) histologically diagnosed at the Department of Pathology, University of Malaya Medical Centre between January 1992 and December 2003 were immunohistochemically studied using a monoclonal antibody to PCNA (Clone PC10: Dako). 20 livers from cases who had succumbed to traumatic injuries served as normal liver controls (NL). PCNA labeling index (PCNA-LI) was determined by counting the number of immunopositive cells in 1000 contiguous HCC, benign cirrhotic perineoplastic liver (BLC), benign perineoplastic non-cirrhotic (BLNC) and NL cells and conversion to a percentage. The PCNA-LI was also expressed as Ojanguren et al's grades. PCNA was expressed in 10% NL, 38.9% BLNC, 76.2% BLC and 71.8% HCC with BLNC, BLC and HCC showing significantly increased (p cells being immunopositive) immunoreactivity on Ojanguren et al's grading system and only HCC demonstrated immunoreactivity which ranged up to grade 3 (75% of cells). From this study, there appears to be a generally increasing trend of proliferative activity from NL to BLNC to BLC and HCC. Nonetheless, BLNC and BLC, like NL, retained low PCNA-LI and only HCC had a significantly increased PCNA-LI compared with the benign categories. This is probably related to the malignant nature of HCC and may reflect the uncontrolled proliferation of the neoplastic hepatocytes. PMID:18376794

  16. Activated human γδ T cells induce peptide-specific CD8+ T-cell responses to tumor-associated self-antigens.

    Altvater, Bianca; Pscherer, Sibylle; Landmeier, Silke; Kailayangiri, Sareetha; Savoldo, Barbara; Juergens, Heribert; Rossig, Claudia

    2012-03-01

    Specific cellular immunotherapy of cancer requires efficient generation and expansion of cytotoxic T lymphocytes (CTLs) that recognize tumor-associated self-antigens. Here, we investigated the capacity of human γδ T cells to induce expansion of CD8+ T cells specific for peptides derived from the weakly immunogenic tumor-associated self-antigens PRAME and STEAP1. Coincubation of aminobisphosphonate-stimulated human peripheral blood-derived γδ T cells (Vγ9+Vδ2+), loaded with HLA-A*02-restricted epitopes of PRAME, with autologous peripheral blood CD8+ T cells stimulated the expansion of peptide-specific cytolytic effector memory T cells. Moreover, peptide-loaded γδ T cells efficiently primed antigen-naive CD45RA+ CD8+ T cells against PRAME peptides. Direct comparisons with mature DCs revealed equal potency of γδ T cells and DCs in inducing primary T-cell responses and peptide-specific T-cell activation and expansion. Antigen presentation by γδ T-APCs was not able to overcome the limited capacity of peptide-specific T cells to interact with targets expressing full-length antigen. Importantly, T cells with regulatory phenotype (CD4+ CD25hiFoxP3+) were lower in cocultures with γδ T cells compared to DCs. In summary, bisphosphonate-activated γδ T cells permit generation of CTLs specific for weakly immunogenic tumor-associated epitopes. Exploiting this strategy for effective immunotherapy of cancer requires strategies that enhance the avidity of CTL responses to allow for efficient targeting of cancer. PMID:21928126

  17. Loss of phosphoinositide 3-kinase γ decreases migration and activation of phagocytes but not T cell activation in antigen-induced arthritis

    Wetzker Reinhard

    2010-04-01

    Full Text Available Abstract Background Phosphoinositide 3-kinase γ (PI3Kγ has been depicted as a major regulator of inflammatory processes, including leukocyte activation and migration towards several chemokines. This study aims to explore the role of PI3Kγ in the murine model of antigen-induced arthritis (AIA. Methods Development of AIA was investigated in wildtype and PI3Kγ-deficient mice as well as in mice treated with a specific inhibitor of PI3Kγ (AS-605240 in comparison to untreated animals. Inflammatory reactions of leukocytes, including macrophage and T cell activation, and macrophage migration, were studied in vivo and in vitro. Results Genetic deletion or pharmacological inhibition of PI3Kγ induced a marked decrease of clinical symptoms in early AIA, together with a considerably diminished macrophage migration and activation (lower production of NO, IL-1β, IL-6. Also, macrophage and neutrophil infiltration into the knee joint were impaired in vivo. However, T cell functions, measured by cytokine production (TNFα, IFNγ, IL-2, IL-4, IL-5, IL-17 in vitro and DTH reaction in vivo were not altered, and accordingly, disease developed normally at later timepoints Conclusion PI3Kγ specifically affects phagocyte function in the AIA model but has no impact on T cell activation.

  18. Inhibition of antigen-presenting activity of dendritic cells resulting from UV irradiation of murine skin is restored by in vitro photorepair of cyclobutane pyrimidine dimers

    Exposing skin to UVB (280-320 nm) radiation suppresses contact hypersensitivity by a mechanism that involves an alteration in the activity of cutaneous antigen-presenting cells (APC). UV-induced DNA damage appears to be an important molecular trigger for this effect. The specific target cells in the skin that sustain DNA damage relevant to the immunosuppressive effect have yet to be identified. We tested the hypothesis that UV-induced DNA damage in the cutaneous APC was responsible for their impaired ability to present antigen after in vivo UV irradiation. Cutaneous APC were collected from the draining lymph nodes of UVB-irradiated, hapten-sensitized mice and incubated in vitro with liposomes containing a photolyase, which, upon absorption of photoreactivating light, splits UV-induced cyclobutane pyrimidine dimers. Photosome treatment followed by photoreactivating light reduced the number of dimer-containing APC, restored the in vivo antigen-presenting activity of the draining lymph node cells, and blocked the induction of suppressor T cells. Neither Photosomes nor photoreactivating light alone, nor photoreactivating light given before Photosomes, restored APC activity, and Photosomes treatment did not reverse the impairment of APC function when isopsoralen plus UVA (320-400 nm) radiation was used instead of UVB. These controls indicate that the restoration of APC function matched the requirements of Photosome-mediated DNA repair for dimers and post-treatment photoreactivating light. These results provide compelling evidence that it is UV-induced DNA damage in cutaneous APC that leads to reduced immune function

  19. Antigen Delivery with Poly(Propylacrylic Acid) Conjugation Enhances MHC-1 Presentation and T-Cell Activation

    Flanary, Suzanne; Hoffman, Allan S.; Stayton, Patrick S.

    2009-01-01

    While many infectious diseases are controlled by vaccine strategies, important limitations continue to motivate the development of better antigen delivery systems. This study focuses on the use of a pH-sensitive polymeric carrier based on poly(propylacrylic acid) (PPAA) to address the need for more potent CD8 cytotoxic T-cell (CTL) responses. An MHC-1/CD8 CTL cell model system with ovalbumin as the protein antigen was used to test whether PPAA could enhance the delivery of ovalbumin into the ...

  20. Local active gingival immunization by a 3,800-molecular-weight streptococcal antigen in protection against dental caries.

    Lehner, T.; Mehlert, A; Caldwell, J

    1986-01-01

    Local gingival immunization was attempted in an effort to confine the immune response to the oral cavity and bypass the systemic immune response. A low-molecular-weight (3.8K) streptococcal antigen (SA) I/II was applied 10 times over a period of 1 year to the gingival crevices of rhesus monkeys. The antigen was maintained in situ by means of silicone rubber appliances. Serial examinations over a period of 1 year showed that topical gingival immunization with the 3.8K SA results in a significa...

  1. Surface-enhanced Raman scattering (SERS) detection of multiple viral antigens using magnetic capture of SERS-active nanoparticles

    A highly sensitive immunoassay based on surface-enhanced Raman scattering (SERS) spectroscopy has been developed for multiplex detection of surface envelope and capsid antigens of the viral zoonotic pathogens West Nile virus (WNV) and Rift Valley fever virus (RVFV). Detection was mediated by antibo...

  2. Antigen-receptor interaction requirement for conjugate formation and lethal-hit triggering by cytotoxic T lymphocytes can be bypassed by protein kinase C activators and Ca2+ ionophores

    The authors show that phorbol esters and Ca2+ ionophores can trigger the lysis of nonantigen-bearing target cells by cytotoxic T lymphocytes. This effect obviates the requirement for antigen-receptor-mediated recognition of the antigen; the intensity of lysis is dose and Ca2+ dependent and requires contact between cytotoxic T lymphocytes and target cells. Using a fluorescence-activated cell sorter to enumerate cytotoxic T lymphocyte-target cell conjugates, they show that phorbol esters at concentrations that triggered lysis of non-antigen-bearing target cells also increased the number of stable conjugates with these target cells. The results point to the importance of the antigen-nonspecific engagements of cytotoxic T lymphocytes in immunologic surveillance. The data also show that the linkage between the T-cell receptor and antigen is not mandatory for conjugate formation, for the strengthening of conjugates, and for lysis

  3. [Antigenic response against PPD and antigen 60 in tubercular patients: single antigen versus the combined test].

    Máttar, S; Broquetas, J M; Gea, J; Aran, X; el-Banna, N; Sauleda, J; Torres, J M

    1992-05-01

    We analyze serum samples from 70 patients with pulmonary tuberculosis and 50 healthy individuals. The antigenic activity (IgG) against protein purified antigen (PPD) and antigen 60 (A60) from M. tuberculosis. Thirteen patients were also HIV infected, and three patients had AIDS defined by the presence of disseminated tuberculosis. The test using antigen alone showed a 77% sensitivity and 74% specificity when PPD is used. When A60 was used, both values improved (81% sensitivity, 94% specificity). The use of a combined test (PPD and A60) improves the sensitivity (89%) but reduces the specificity (82%). The HIV infected patients showed similar responses to those of other patients. The combined use of different antigens might be useful for diagnosing tuberculosis. PMID:1390996

  4. Mycobacterium tuberculosis MmsA, a novel immunostimulatory antigen, induces dendritic cell activation and promotes Th1 cell-type immune responses.

    Kim, Jong-Seok; Kim, Woo Sik; Choi, Hong-Hee; Kim, Hong Min; Kwon, Kee Woong; Han, Seung Jung; Cha, Seung Bin; Cho, Sang-Nae; Koh, Won-Jung; Shin, Sung Jae

    2015-01-01

    Mycobacterium tuberculosis (Mtb), the causative agent of tuberculosis, is an outstanding pathogen that modulates the host immune response. This inconvenient truth drives the continual identification of antigens that generate protective immunity, including Th1-type T cell immunity. Here, the contribution of methylmalonate semialdehyde dehydrogenase (MmsA, Rv0753c) of Mtb to immune responses was examined in the context of dendritic cell (DC) activation and T cell immunity both in vitro and in vivo. The results showed that MmsA induced DC activation by activating the MAPK and NF-κB signaling pathways. Additionally, MmsA-treated DCs activated naïve T cells, effectively polarized CD4(+) and CD8(+) T cells to secrete IFN-γ and IL-2, and induced T cell proliferation. These results indicate that MmsA is a novel DC maturation-inducing antigen that drives the Th1 immune response. Thus, MmsA was found to potentially regulate immune responses via DC activation toward Th1-type T cell immunity, enhancing our understanding of Mtb pathogenesis. PMID:26507911

  5. A new scorpion venom toxin paralytic to insects that affects Na+ channel activation. Purification, structure, antigenicity and mode of action.

    Borchani, L.; Mansuelle, P.; Stankiewicz, M; Grolleau, F.; Cestèle, S.; Karoui, H.; Lapied, B; Rochat, H; Pelhate, M.; El Ayeb, M.

    1996-01-01

    International audience A new toxin, BotIT2, with a unique mode of action on the isolated giant axon of the cockroach Periplaneta americana and DUM (dorsal unpaired median) neurons, has been purified from the venom of the scorpion Buthus occitanus tunetanus. Its structural, antigenic and pharmacological properties are compared to those of three other groups of neurotoxins found in Buthidae scorpion venoms. Like excitatory, depressant and alpha-type insect-selective neurotoxins, BotIT2 is to...

  6. Carcinoma-associated antigens

    This invention relates to novel antigens associated with breast carcinoma, anti-sera specific to said antigens, 125I-labeled forms of said antigens and methods of detecting said antigens in serum or plasma. The invention also relates to a diagnostic kit containing standardised antigens or antisera or marked forms thereof for the detection of said antigens in human blood, serum or plasma. (author)

  7. Interleukin-2 (rIL-2)-induced lymphokine-activated killer (LAK) cells and their precursors express the VGO1 antigen

    Precursor and effector cells of recombinant interleukin-2 (r-IL-2)-induced lymphokine-activated killer (LAK) activity were investigated for their expression of VGO1. Peripheral blood lymphocytes (PBL) from normal donors were purified and separated in a FACS 420 into VGO1+- and VGO1- cell fractions before and after culture for 96 hr with 100 U/ml of r-IL-2. Their lytic activity against K 562 and Daudi cells was measured in a 51Cr release assay. The majority, if not all, of the LAK effector and precursor cells was VGO1+ lymphocytes. The expression of VGO1 by LAK precursor cells remained stable under the culture conditions used in our experiments. VGO1- lymphocytes cultured with r-IL-2 demonstrated neither LAK-induced activity nor expression of VGO1 antigen

  8. A Kinase Activity Associated with Simian Virus 40 Large T Antigen Phosphorylates Upstream Binding Factor (UBF) and Promotes Formation of a Stable Initiation Complex between UBF and SL1

    Zhai, Weiguo; Comai, Lucio

    1999-01-01

    Simian virus 40 large T antigen is a multifunctional protein which has been shown to modulate the expression of genes transcribed by RNA polymerase I (Pol I), II, and III. In all three transcription systems, a key step in the activation process is the recruitment of large T antigen to the promoter by direct protein-protein interaction with the TATA binding protein (TBP)-TAF complexes, namely, SL1, TFIID, and TFIIIB. However, our previous studies on large T antigen stimulation of Pol I transcr...

  9. Resveratrol Suppresses Cytokine Production Linked to FcεRI-MAPK Activation in IgE-Antigen Complex-Exposed Basophilic Mast Cells and Mice.

    Han, Seon-Young; Choi, Yean-Jung; Kang, Min-Kyung; Park, Jung Han Yoon; Kang, Young-Hee

    2015-01-01

    A complicated interplay between resident mast cells and other recruited inflammatory cells contributes to the development and progression of allergic inflammation entailing the promotion of T helper 2 (Th2) cytokine responses. The current study examined whether resveratrol suppressed the production of inflammatory Th2 cytokines in cultured rat basophilic leukemia RBL-2H3 cells. Cells pre-treated with resveratrol nontoxic at 1–25 μM were sensitized with anti-dinitrophenyl (anti-DNP), and subsequently stimulated by dinitrophenyl-human serum albumin (DNP–HSA) antigen. Resveratrol dose-dependently diminished the secretion of interleukin (IL)-3, IL-4, IL-13 as well as tumor necrosis factor (TNF)-α by the antigen stimulation from sensitized cells. It was found that resveratrol mitigated the phosphorylation of p38 MAPK, ERK, and JNK elevated in mast cells exposed to Fc epsilon receptor I (FcεRI)-mediated immunoglobulin E (IgE)-antigen complex. The FcεRI aggregation was highly enhanced on the surface of mast cells following the HSA stimulation, which was retarded by treatment with 1–25 μM resveratrol. The IgE-receptor engagement rapidly induced tyrosine phosphorylation of c-Src-related focal adhesion protein paxillin involved in the cytoskeleton rearrangement. The FcεRI-mediated rapid activation of c-Src and paxillin was attenuated in a dose-dependent manner. In addition, the paxillin activation entailed p38 MAPK and ERK-responsive signaling, but the JNK activation was less involved. Consistently, oral administration of resveratrol reduced the tissue level of phosphorylated paxillin in the dorsal skin of DNP–HSA-challenged mice. The other tyrosine kinase Tyk2-STAT1 signaling was activated in the dorsal epidermis of antigen-exposed mice, which was associated with allergic inflammation. These results showed that resveratrol inhibited Th2 cytokines- and paxillin-linked allergic responses dependent upon MAPK signaling. Therefore, resveratrol may possess the

  10. Immunological recovery and dose evaluation in IFN-alpha treatment of hairy cell leukemia: analysis of leukocyte differentiation antigens, NK and 2',5'-oligoadenylate synthetase activity

    Nielsen, B; Hokland, M; Justesen, J;

    1989-01-01

    A low-dose interferon (IFN)-alpha regimen for the treatment of hairy cell leukemia (HCL) was evaluated by following changes in leukocyte differentiation antigens (LDA), natural killer cell (NK) and 2',5'-oligoadenylate (2-5A) synthetase activities. Due to hairy cells' (HC) weak expression of...... treatment these effects were gradually abolished, indicating an increasing effect of IFN-alpha in vivo with time. These results shows that the different PBMNC subpopulations and important immunological functions normalize with treatment. This normalization is, however, not seen until at least after 1 year...

  11. B cell antigen receptor-induced activation of an IRAK4-dependent signaling pathway revealed by a MALT1-IRAK4 double knockout mouse model

    Dufner Almut

    2011-03-01

    Full Text Available Abstract Background The B cell antigen receptor (BCR and pathogen recognition receptors, such as Toll-like receptor 4 (TLR4, act in concert to control adaptive B cell responses. However, little is known about the signaling pathways that integrate BCR activation with intrinsic TLR4 stimulation. Antigen receptors initialize activation of the inducible transcription factor nuclear factor-κB (NF-κB via recruitment of the membrane-associated guanylate kinase caspase recruitment domain protein 11 (CARD11, the adapter molecule B cell CLL/lymphoma 10 (BCL10, and the "paracaspase" mucosa-associated lymphoid tissue lymphoma translocation gene 1 (MALT1 into lipid rafts. Upon BCR triggering, this activation strictly depends on BCL10, but not on MALT1, leading to the hypothesis that a MALT1-independent NF-κB activation pathway contributes to BCR-induced NF-κB activation downstream of BCL10. The identity of this pathway has remained elusive. Results Using genetic and biochemical approaches, we demonstrate that the IRAK4- and IRAK1-dependent TLR signaling branch is activated upon BCR triggering to induce partial NF-κB activation. BCR-induced MALT1-independent IκB degradation and B cell proliferation were inhibited in MALT1/IRAK4 double knockout B cells. Moreover, IRAK1 was recruited into lipid rafts upon BCR stimulation and activated following transient recruitment of IRAK4. Conclusion We propose that the observed crosstalk between BCR and TLR signaling components may contribute to the discrimination of signals that emanate from single and dual receptor engagement to control adaptive B cell responses.

  12. OX48, a monoclonal antibody against a 70,000 MW rat activation antigen expressed by T cells bearing the high-affinity interleukin-2 receptor.

    Somoza, C; Fernández-Ruiz, E; Rebollo, A; Sanz, E; Ramírez, F; Silva, A

    1990-01-01

    The monoclonal antibody (mAb) OX48 recognizes a 70,000 MW cell-surface protein present in a small percentage of activated rat T cells and in CD8+ rat x BW5147 interleukin-2 (IL-2)-dependent T-cell hybridomas, but not in resting spleen cells or in IL-2-independent T-cell hybrids. OX48 antibody added simultaneously with concanavalin A (Con A) to resting spleen cells inhibits the cell proliferation and reduces the IL-2 production. However, addition of IL-2 does not restore the mitogenic response. Growth of rat blast T cells or IL-2-dependent hybrids is not affected by the OX48 antibody. There is a close correlation between the expression of high-affinity IL-2 receptors (IL-2R) and the OX48 antigen in T-cell hybridomas. In spite of this striking correlation, OX48 mAb does not inhibit the binding of 125I-IL-2 to the IL-2-dependent hybrids, and is unable to immunoprecipitate any of the proteins chemically cross-linked to 125I-IL-2. Therefore, the OX48 molecule represents a new rat activation antigen, undefined in other species, and probably involved in the early steps of T-cell activation. Images Figure 5 Figure 7 PMID:2373518

  13. Blastogenic response of human lymphocytes to early antigen(s) of human cytomegalovirus.

    Waner, J L; Kong, N; Biano, S

    1983-01-01

    The lymphocytes of asymptomatic, seropositive donors demonstrated blastogenic responses to early antigens of human cytomegalovirus whether or not antibodies to early antigens were detectable. The lymphocytes of six of nine patients with active cytomegalovirus infections gave stimulation indexes of greater than or equal to 2.00 with antigens of productively infected cells, whereas only two patients demonstrated comparable stimulation indexes with early antigens. Four patients with stimulation ...

  14. Elevated 68Ga Prostate-Specific Membrane Antigen Activity in Metastatic Non-Small Cell Lung Cancer.

    Shetty, Deepa; Loh, Han; Bui, Chuong; Mansberg, Robert; Stevanovic, Amanda

    2016-05-01

    A 71-year-old man with a background of treated stage IIIB non-small cell lung cancer was referred for Ga prostate-specific membrane antigen (PSMA) PET/CT for staging of prostate cancer. In addition to the PSMA uptake in the known prostate malignancy, the study also demonstrated increased PSMA uptake in an enlarging left lower lobe lung mass with diffusely increased PSMA uptake in an enlarged thyroid gland and bilateral enlarged supraclavicular lymph nodes. Fine-needle aspiration biopsy of the thyroid gland and a left supraclavicular lymph node demonstrated metastatic adenocarcinoma from a primary lung cancer. PMID:26828144

  15. Mycobacterial antigen driven activation of CD14++CD16- monocytes is a predictor of tuberculosis-associated immune reconstitution inflammatory syndrome.

    Bruno B Andrade

    2014-10-01

    Full Text Available Paradoxical tuberculosis-associated immune reconstitution inflammatory syndrome (TB-IRIS is an aberrant inflammatory response occurring in a subset of TB-HIV co-infected patients initiating anti-retroviral therapy (ART. Here, we examined monocyte activation by prospectively quantitating pro-inflammatory plasma markers and monocyte subsets in TB-HIV co-infected patients from a South Indian cohort at baseline and following ART initiation at the time of IRIS, or at equivalent time points in non-IRIS controls. Pro-inflammatory biomarkers of innate and myeloid cell activation were increased in plasma of IRIS patients pre-ART and at the time of IRIS; this association was confirmed in a second cohort in South Africa. Increased expression of these markers correlated with elevated antigen load as measured by higher sputum culture grade and shorter duration of anti-TB therapy. Phenotypic analysis revealed the frequency of CD14(++CD16(- monocytes was an independent predictor of TB-IRIS, and was closely associated with plasma levels of CRP, TNF, IL-6 and tissue factor during IRIS. In addition, production of inflammatory cytokines by monocytes was higher in IRIS patients compared to controls pre-ART. These data point to a major role of mycobacterial antigen load and myeloid cell hyperactivation in the pathogenesis of TB-IRIS, and implicate monocytes and monocyte-derived cytokines as potential targets for TB-IRIS prevention or treatment.

  16. Targeted delivery of lipid antigen to macrophages via the CD169/sialoadhesin endocytic pathway induces robust invariant natural killer T cell activation

    Kawasaki, Norihito; Vela, Jose Luis; Nycholat, Corwin M.; Rademacher, Christoph; Khurana, Archana; van Rooijen, Nico; Crocker, Paul R.; Kronenberg, Mitchell; Paulson, James C.

    2013-01-01

    Invariant natural killer T (iNKT) cells induce a protective immune response triggered by foreign glycolipid antigens bound to CD1d on antigen-presenting cells (APCs). A limitation of using glycolipid antigens to stimulate immune responses in human patients has been the inability to target them to the most effective APCs. Recent studies have implicated phagocytic CD169+ macrophages as major APCs in lymph nodes for priming iNKT cells in mice immunized with glycolipid antigen in particulate form...

  17. Development of tools to target antigen through mannose receptor

    Abbas, Zaigham

    2011-01-01

    Dendritic cells (DC) are unique antigen presenting cells which play a major role in antigen presentation and initiation of the immune response by regulating B- and T- cell activation. Antigen targeting to DC receptors is an effective, safe and specific method for vaccine development. The mannose receptor (MR) is an endocytic receptor expressed by subpopulations of DC and antigen targeting through MR leads to enhanced antigen uptake and presentation to T -cells. This makes MR a favourite recep...

  18. Antibodies against a class II HLA-peptide complex raised by active immunization of mice with antigen mimicking peptides

    Dam-Tuxen, R; Riise, Erik Skjold

    2009-01-01

    Multiple sclerosis (MS) is an autoimmune disease linked to the human leucocyte antigen (HLA) class II genes DRB1*1501, DRB5*0101 and DQB1*0602. T cells reactive towards the DRB1*1501 in complex with various peptides derived from myelin basic protein (MBP), which is the major component of myelin......, have been found in the peripheral blood of MS patients. These autoreactive T cells are believed to play a role in the pathogenesis of MS. In this article, antibodies against the HLA complex DR2b (DRA1*0101/DRB1*1501) in complex with the MBP-derived peptide MBP(85-99) have been generated by immunization...

  19. Tumor Antigen Specific Activation of Primary Human T-Cells Expressing a Virally Encoded Chimeric T-Cell Receptor Specific for p185HER2

    杨建民; MichaelSFRIEDMAN; ChristopherMREYNOLDS; MarianneTHUBEN; LeeWILKE; JenniferFULLER; 李桥; ZeligESHHAR; JamesJMULE; KevimTMCDONAGH

    2004-01-01

    We have developed and tested chimeric T-cell receptors (TCR) specific for p185HER2. In these experiments,retroviral vectors expressing the N297 or N29ξ receptors were constructed in pRET6. Amphotropic viral producer cells were established in the GALV-based PG13 packaging cell line. Ficoll purified human peripheral blood lymphocytes (PBL) were vitally transduced using an optimized protocol incorporating activation with immobilized anti-CD3/anti-CD28 monoclonal antibodies, followed by viral infection in the presence of fibronectin fragment CH296. Transduced cells were co-cultured with human tumor cell lines that overexpress (SK-OV-3) or underexpress (MCF7) p185HER2 to assay for antigen specific immune responses. Both CD4+ and CD8+ T-cells transduced with the N297 or N29ξ chTCR demonstrated HER2-specific antigen responses, as determined by release of Th1 like cytokines, and cellular cytotoxicity assays. Our results support the feasibility of adoptive immunothempy with genetically modified T-cells expressing a chTCR specific for p185HER2.

  20. Antigenic contents of Treponema pallidum preparations.

    Wos, S M; Wicher, K

    1986-01-01

    In investigations of syphilis various Treponema pallidum antigens are used to study the immune responses of naturally or experimentally infected hosts. In the past these antigen preparations have rarely been examined for their antigenic contents and activity. In the present study, supernatant, sediment, and solubilised preparations of T pallidum Nichols strain (20 X 10(9) organisms/ml) and T phagedenis biotype Reiter were examined by modified counterimmunoelectrophoresis and immunoblotting fo...

  1. Antigen-specific IL-23/17 pathway activation by murine semi-mature DC-like cells

    We analyzed the phenotype and function of bone marrow-derived dendritic cells (DCs) induced in vitro without using any serum during the late stage of cultivation. These 'serum-free' DCs (SF-DCs) possessed the ability to induce T cell proliferation as well as antibody responses, indicating that they were functional DCs. Surprisingly, the SF-DCs akin to semi-mature DCs in terms of both phenotypic and functional characteristics. The SF-DCs did not produce IL-12 but produced large amounts of IL-23 following lipopolysaccharide stimulation. The antigen-specific production of IL-17 by CD4+ T cells co-cultured with OVA-loaded SF-DCs was significantly higher than that with OVA-loaded conventional DCs. These results suggest that SF-DCs tend to produce IL-23 and can consequently induce the IL-17 producing CD4+ T cells. The semi-mature DC-like cells reported here will be useful vehicles for DC immunization and might contribute to studies on the possible involvement of semi-mature DCs in Th17 cell differentiation.

  2. Antigen-specific IL-23/17 pathway activation by murine semi-mature DC-like cells

    Nagasaka, Shinya; Iwasaki, Takumi; Okano, Tomoko [Department of Biological Science and Technology, Tokyo University of Science, 2641 Yamazaki, Noda-shi, Chiba 278-8510 (Japan); Chiba, Joe, E-mail: chibaj@rs.noda.tus.ac.jp [Department of Biological Science and Technology, Tokyo University of Science, 2641 Yamazaki, Noda-shi, Chiba 278-8510 (Japan)

    2009-09-11

    We analyzed the phenotype and function of bone marrow-derived dendritic cells (DCs) induced in vitro without using any serum during the late stage of cultivation. These 'serum-free' DCs (SF-DCs) possessed the ability to induce T cell proliferation as well as antibody responses, indicating that they were functional DCs. Surprisingly, the SF-DCs akin to semi-mature DCs in terms of both phenotypic and functional characteristics. The SF-DCs did not produce IL-12 but produced large amounts of IL-23 following lipopolysaccharide stimulation. The antigen-specific production of IL-17 by CD4{sup +} T cells co-cultured with OVA-loaded SF-DCs was significantly higher than that with OVA-loaded conventional DCs. These results suggest that SF-DCs tend to produce IL-23 and can consequently induce the IL-17 producing CD4{sup +} T cells. The semi-mature DC-like cells reported here will be useful vehicles for DC immunization and might contribute to studies on the possible involvement of semi-mature DCs in Th17 cell differentiation.

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

    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...

  4. T-antigen binding lectin with antibacterial activity from marine invertebrate, sea cucumber (Holothuria scabra): possible involvement in differential recognition of bacteria.

    Gowda, Nagaraj M; Goswami, Usha; Khan, M Islam

    2008-10-01

    In invertebrates, cellular and humoral components are evolved to maintain their body immunity and integrity. Both these factors respond to different antigens such as microorganisms, vertebrate erythrocytes and foreign proteins. In this article, we report a study of a lectin (HSL) involved in immune response in the echinoderm, sea cucumber (Holothuria scabra). Correlative studies indicate that the expression of this defensive lectin is induced by bacterial challenge, wherein cell wall glycoconjugates of bacteria are involved in lectin induction. HSL showed strong broad spectrum antibacterial activity against both gram-positive and gram-negative bacteria. Under in vitro conditions, purified HSL mediate agglutination of the test bacteria, there by indicating a possible mode of action in physiological situation. PMID:18501924

  5. Dichotomy of the T cell response to Leishmania antigens in patients suffering from cutaneous leishmaniasis; absence or scarcity of Th1 activity is associated with severe infections

    Gaafar, A; Kharazmi, A; Ismail, A;

    1995-01-01

    The T cell response was studied in 25 patients suffering from cutaneous leishmaniasis caused by Leishmania major with severe (n = 10) and mild (n = 15) disease manifestations. Peripheral blood mononuclear cells (PBMC) from the patients were activated by sonicates of Leishmania promastigotes (LMP......) and amastigotes (LDA), and the surface protease gp63. The proliferative responses to Leishmania antigens were lower in patients with severe disease than in patients with mild disease (P = 0.01-0.05), and such a difference was not observed in the response to purified protein derivative of tuberculin (PPD......) or tetanus toxoid (TT). LMP-induced interferon-gamma (IFN-gamma) production was lower in patients with severe than in patients with mild disease (P Leishmania...

  6. Surface antigen expression in chronic lymphocytic leukemia: clustering analysis, interrelationships and effects of chromosomal abnormalities.

    Hulkkonen, J; Vilpo, L; Hurme, M; Vilpo, J

    2002-02-01

    Chronic lymphocytic leukemia (CLL) is a phenotypically distinguishable form of B-lymphoid leukemias. The regularity of surface membrane antigen expression patterns, their interrelationships as well as the effects of the three frequent chromosomal aberrations, ie 11q deletion, 13q deletion and trisomy 12, were investigated in 35 classic CLL cases by flow cytometry. The two-way cluster analysis of 31 individual antigens revealed three expression patterns: (1) most cells in most cases positive (CD5, CD19, CD20, CD23, CD27, CD40, CD45, CD45RA); (2) most cells in most cases negative (CD10, CD14, CD34, CD122, CD154, mIgG); and (3) a mixed pattern with a variable number of positive cases and a variable percentage of positive cells in individual cases (CD11c, CD21, CD22, CD25, CD38, CD45RO, CD79b, CD80, CD95, CD124, CD126, CD130, FMC7, mIgD, mIgkappa, mIglambda, mIgM). The expressions of several antigens were strongly interdependent, even when antigens belonged to entirely different gene families. Such antigen pairs were: CD11c/CD21; CD19/CD45; CD19/CD79b; CD22/CD45RA; CD23/Igkappa; CD25/mIgM; CD27/CD45; CD45/CD79b; CD45RA/Igkappa. In contrast, the expression of some antigens was mutually exclusive, the best examples being CD45RA/CD45RO, CD38/CD80 and CD45RA/CD80. Deletion of chromosome arm 11q attenuated expression of splicing variant CD45RA, but enhanced CD45RO expression. In contrast, cases of trisomy 12 were associated with enhanced CD45RA and attenuated CD45RO expression. Similarly, trisomy 12 was associated with enhanced CD27 and mIgkappa expression. The variable levels of signaling surface membrane antigens, their interactions and interference by genetic aberrations are likely to affect the clinical progression and drug response of CLL. PMID:11840283

  7. Histocompatibility antigen test

    ... more common in certain autoimmune diseases . For example, HLA-B27 antigen is found in many people (but not ... More Ankylosing spondylitis Autoimmune disorders Bone marrow transplant HLA-B27 antigen Kidney transplant Reactive arthritis Update Date 2/ ...

  8. Nonspecific DNA binding activity of simian virus 40 large T antigen: evidence for the cooperation of two regions for full activity.

    Lin, H J; Upson, R H; Simmons, D T

    1992-01-01

    We generated a series of COOH-terminal truncated simian virus 40 large tumor (T) antigens by using oligonucleotide-directed site-specific mutagenesis. The mutant proteins [T(1-650) to T(1-516)] were expressed in insect cells infected with recombinant baculoviruses. T(1-623) and shorter proteins [T(1-621) to T(1-516)] appeared to be structurally changed in a region between residues 269 and 522, as determined by increased sensitivities to trypsin digestion and by altered reactivities to several...

  9. Early Endosomal Antigen 1 (EEA1) Is an Obligate Scaffold for Angiotensin II-induced, PKC-α-dependent Akt Activation in Endosomes*

    Nazarewicz, Rafal Robert; Salazar, Gloria; Patrushev, Nikolay; Martin, Alejandra San; Hilenski, Lula; Xiong, Shiqin; Alexander, R. Wayne

    2011-01-01

    Akt/protein kinase B (PKB) activation/phosphorylation by angiotensin II (Ang II) is a critical signaling event in hypertrophy of vascular smooth muscle cells (VSMCs). Conventional wisdom asserts that Akt activation occurs mainly in plasma membrane domains. Recent evidence that Akt activation may take place within intracellular compartments challenges this dogma. The spatial identity and mechanistic features of these putative signaling domains have not been defined. Using cell fractionation and fluorescence methods, we demonstrate that the early endosomal antigen-1 (EEA1)-positive endosomes are a major site of Ang II-induced Akt activation. Akt moves to and is activated in EEA1 endosomes. The expression of EEA1 is required for phosphorylation of Akt at both Thr-308 and Ser-473 as well as for phosphorylation of its downstream targets mTOR and S6 kinase, but not for Erk1/2 activation. Both Akt and phosphorylated Akt (p-Akt) interact with EEA1. We also found that PKC-α is required for organizing Ang II-induced, EEA1-dependent Akt phosphorylation in VSMC early endosomes. EEA1 expression enables PKC-α phosphorylation, which in turn regulates Akt upstream signaling kinases, PDK1 and p38 MAPK. Our results indicate that PKC-α is a necessary regulator of EEA1-dependent Akt signaling in early endosomes. Finally, EEA1 down-regulation or expression of a dominant negative mutant of PKC-α blunts Ang II-induced leucine incorporation in VSMCs. Thus, EEA1 serves a novel function as an obligate scaffold for Ang II-induced Akt activation in early endosomes. PMID:21097843

  10. Increase in a distinct pulmonary macrophage subset possessing an antigen-presenting cell phenotype and in vitro APC activity following silica exposure

    Silica inhalation results in chronic lung inflammation and fibrosis. While the role of the alveolar macrophage (AM) is considered key to the effects of silica on lung pathology, the etiology is not completely understood. Evidence suggests an increase in antigen presenting cell (APC) activity as a contributing factor to this process, as well as potential roles for both AM and interstitial macrophages (IM) in silicosis. In order to study the effects of crystalline silica on the APC activity of pulmonary macrophages, mice were exposed intranasally and changes in pulmonary macrophage populations were assessed using flow cytometry. Following intranasal instillation of silica, a significant increase in the APC activity of AM was observed, as well as a significant increase in a subset of IM expressing classic APC markers (MHC class II, CD11c). In addition, an in vitro system using bone marrow-derived macrophages (BMDM) was generated to assess the effects of silica on the APC activity of macrophages in vitro. Data using BMDM in the in vitro APC assay demonstrated a significant increase in APC activity following silica exposure, but not following exposure to saline or a control particle (TiO2). Using a combination of in vivo and in vitro experiments, the current study describes a significant increase in an interstitial macrophage subset with an APC phenotype, as well as an increase in the APC activity of both AM and BMDM, as a direct result of exposure to crystalline silica. These studies suggest a specific mechanism, macrophage subset activation, by which crystalline silica exposure results in chronic pulmonary inflammation and, eventually, fibrosis

  11. Molecular definition of a polymorphic antigen (LA45) of free HLA-A and -B heavy chains found on the surfaces of activated B and T cells.

    Madrigal, J A; Belich, M P; Benjamin, R J; Little, A M; Hildebrand, W H; Mann, D L; Parham, P

    1991-11-01

    A monomoprhic monoclonal antibody (LA45 antibody) reactive with "a new activation-induced surface structure on human T lymphocytes" (LA45 antigen) that resembled free class I heavy chains has recently been described (Schnabl, E., H. Stockinger, O. Majdic, H. Gaugitsch, I.J.D. Lindley, D. Maurer, A. Hajek-Rosenmayr, and W. Knapp. 1990. J. Exp. Med. 171:1431). This antibody was used to clone a class I-like heavy chain (LA45 gene) from the HUT 102 tumor cell, which paradoxically did not give rise to the LA45 antigen on transfection into monkey COS cells. We show here that the LA45 gene is HLA-Aw66.2, a previously uncharacterized allele of the HLA-A locus. The previously determined LA45 sequence differs from that of HLA-Aw66.2, from HUT 102, and the CR-B B cell line derived from the same individual as HUT 102 by substitution of tryptophan for serine at position 4 in the alpha 1 domain. Transfection of HLA-Aw66.2, and of a mutant of this gene with serine 4 substituted for tryptophan, into a human B cell line (C1R) both resulted in expression of the LA45 epitope. Furthermore, we find expression of the LA45 epitope on Epstein Barr virus-transformed B cell lines as well as lectin-activated T cells, but not on long-term T cell lines or unstimulated peripheral blood T cells. The specificity of the LA45 antibody is polymorphic and the presence of the LA45 epitope is precisely correlated with the sequence arginine, asparagine (RN) at residues 62 and 63 of the helix of the alpha 1 domain. The LA45 epitope is broadly distributed, being associated with half the alleles of both HLA-A and -B loci but none of the HLA-C locus. All the results are consistent with the presence of pools of free HLA-A and -B heavy chains at the surfaces of certain cell types but not others. Such molecules are probably responsible for the HLA-associated class I alloantigens of lectin-activated T cells. We hypothesize the free heavy chains result from dissociation of beta 2-microglobulin from

  12. Prospective evaluation of a whole-blood test using Mycobacterium tuberculosis-specific antigens ESAT-6 and CFP-10 for diagnosis of active tuberculosis

    Ravn, Pernille; Munk, Martin E; Andersen, Ase B;

    2005-01-01

    A new immunodiagnostic test based on the Mycobacterium tuberculosis-specific antigens CFP-10/ESAT-6(QFT-RD1) has been launched as an aid in the diagnosis of latent tuberculosis (TB) infection (LTBI). The aim of this study was to evaluate this test for the diagnosis of active TB. Eighty-two patients...... with suspicion of TB and 39 healthy BCG-vaccinated persons were enrolled. Forty-eight had active TB, 25 did not, and 9 were excluded. Sensitivity and specificity of the test for active TB were evaluated in a prospective blinded manner in patients suspected of TB. The sensitivity of the QFT-RD1 was 85......% (40/48; confidence interval [CI], 75 to 96), and it was higher than the sensitivity of microscopy, 42% (20/48; CI, 27 to 56; P = 0.001), and culture, 59% (27/46; CI, 44 to 73; P = 0.009). Of patients with extrapulmonary TB, 92% (12/13) were QFT-RD1 positive, whereas only 31% (4/13) were positive by...

  13. Clonality Analysis of Immunoglobulin Gene Rearrangement by Next-Generation Sequencing in Endemic Burkitt Lymphoma Suggests Antigen Drive Activation of BCR as Opposed to Sporadic Burkitt Lymphoma

    Amato, Teresa; Abate, Francesco; Piccaluga, Pierpaolo; Iacono, Michele; Fallerini, Chiara; Renieri, Alessandra; De Falco, Giulia; Ambrosio, Maria Raffaella; Mourmouras, Vaselious; Ogwang, Martin; Calbi, Valeria; Rabadan, Roul; Hummel, Michael; Pileri, Stefano; Bellan, Cristiana

    2016-01-01

    Objectives: Recent studies using next-generation sequencing (NGS) analysis disclosed the importance of the intrinsic activation of the B-cell receptor (BCR) pathway in the pathogenesis of sporadic Burkitt lymphoma (sBL) due to mutations of TCF3/ID3 genes. Since no definitive data are available on the genetic landscape of endemic Burkitt (eBL), we first assessed the mutation frequency of TCF3/ID3 in eBL compared with sBL and subsequently the somatic hypermutation status of the BCR to answer whether an extrinsic activation of BCR signaling could also be demonstrated in Burkitt lymphoma. Methods: We assessed the mutations of TCF3/ID3 by RNAseq and the BCR status by NGS analysis of the immunoglobulin genes (IGs). Results: We detected mutations of TCF3/ID3 in about 30% of the eBL cases. This rate is significantly lower than that detected in sBL (64%). The NGS analysis of IGs revealed intraclonal diversity, suggesting an active targeted somatic hypermutation process in eBL compared with sBL. Conclusions: These findings support the view that the antigenic pressure plays a key role in the pathogenetic pathways of eBL, which may be partially distinct from those driving sBL development. PMID:26712879

  14. Cellular size as a means of tracking mTOR activity and cell fate of CD4+ T cells upon antigen recognition.

    Kristen N Pollizzi

    Full Text Available mTOR is a central integrator of metabolic and immunological stimuli, dictating immune cell activation, proliferation and differentiation. In this study, we demonstrate that within a clonal population of activated T cells, there exist both mTORhi and mTORlo cells exhibiting highly divergent metabolic and immunologic functions. By taking advantage of the role of mTOR activation in controlling cellular size, we demonstrate that upon antigen recognition, mTORhi CD4+ T cells are destined to become highly glycolytic effector cells. Conversely, mTORlo T cells preferentially develop into long-lived cells that express high levels of Bcl-2, CD25, and CD62L. Furthermore, mTORlo T cells have a greater propensity to differentiate into suppressive Foxp3+ T regulatory cells, and this paradigm was also observed in human CD4+ T cells. Overall, these studies provide the opportunity to track the development of effector and memory T cells from naïve precursors, as well as facilitate the interrogation of immunologic and metabolic programs that inform these fates.

  15. Discrimination between Active and Latent Tuberculosis Based on Ratio of Antigen-Specific to Mitogen-Induced IP-10 Production

    Jeong, Yun Hee; Hur, Yun-Gyoung; Lee, Hyejon; Kim, Sunghyun; Cho, Jang-Eun; Chang, Jun; Shin, Sung Jae; Lee, Hyeyoung; Kang, Young Ae; Cho, Sang-Nae; Ha, Sang-Jun

    2014-01-01

    Mycobacterium tuberculosis is the major causative agent of tuberculosis (TB). The gamma interferon (IFN-γ) release assay (IGRA) has been widely used to diagnose TB by testing cell-mediated immune responses but has no capacity for distinguishing between active TB and latent TB infection (LTBI). This study aims to identify a parameter that will help to discriminate active TB and LTBI. Whole-blood samples from 33 active TB patients, 20 individuals with LTBI, and 26 non-TB controls were applied t...

  16. Design and synthesis of peptide conjugates of phosphoramide mustard as prodrugs activated by prostate-specific antigen.

    Wu, Xinghua; Hu, Longqin

    2016-06-15

    A series of Glutaryl-Hyp-Ala-Ser-Chg-Gln-4-aminobenzyl phosphoramide mustard conjugates (1a-e) was designed and synthesized as potential prodrugs for site-specific activation by PSA in prostate cancer cells. All conjugates were found to be substrates of PSA with cleavage occurring between Gln and the para-aminobenzyl (PAB) linker. Structure-activity relationship studies on these conjugates indicated that introduction of electron-withdrawing fluorine(s) on the phenyl ring in the PAB linker uniformly improved the chemical stability of the conjugates while the position of substitution affected differently the self-immolative process of conjugates upon proteolysis. Introduction of a fluorine at ortho position to benzylic phosphoramide as in 1b results in better stability of the conjugate prior to activation while maintaining its antiproliferative activity upon activation by PSA. The conjugate 1b with 2-fluoro substitution was identified as a promising lead for further evaluation and optimization in the development of prostate cancer-targeted prodrugs. PMID:27156193

  17. Detection of Mycobacterial Antigens in Leprosy Serum Immune Complex

    1986-01-01

    The antigens from immune complexes of sera from patients with mycobacterial diseases were released by sodium dodecyl sulfate. The antigenic activity of the released proteins was tested by agar gel diffusion and immunoelectrophoresis. This simple method provided direct evidence for the presence of mycobacterial antigens in the immune complexes of sera from patients with leprosy and tuberculosis.

  18. Cross-platform expression profiling demonstrates that SV40 small tumor antigen activates Notch, Hedgehog, and Wnt signaling in human cells

    We previously analyzed human embryonic kidney (HEK) cell lines for the effects that simian virus 40 (SV40) small tumor antigen (ST) has on gene expression using Affymetrix U133 GeneChips. To cross-validate and extend our initial findings, we sought to compare the expression profiles of these cell lines using an alternative microarray platform. METHODS: We have analyzed matched cell lines with and without expression of SV40 ST using an Applied Biosystems (AB) microarray platform that uses single 60-mer oligonucleotides and single-color quantitative chemiluminescence for detection. RESULTS: While we were able to previously identify only 456 genes affected by ST with the Affymetrix platform, we identified 1927 individual genes with the AB platform. Additional technical replicates increased the number of identified genes to 3478 genes and confirmed the changes in 278 (61%) of our original set of 456 genes. Among the 3200 genes newly identified as affected by SV40 ST, we confirmed 20 by QRTPCR including several components of the Wnt, Notch, and Hedgehog signaling pathways, consistent with SV40 ST activation of these developmental pathways. While inhibitors of Notch activation had no effect on cell survival, cyclopamine had a potent killing effect on cells expressing SV40 ST. CONCLUSIONS: These data show that SV40 ST expression alters cell survival pathways to sensitize cells to the killing effect of Hedgehog pathway inhibitors

  19. A Neoglycoconjugate Containing the Human Milk Sugar LNFPIII Drives Anti-Inflammatory Activation of Antigen Presenting Cells in a CD14 Dependent Pathway.

    Smanla Tundup

    Full Text Available The milk pentasaccharide LNFPIII has therapeutic action for metabolic and autoimmune diseases and prolongs transplant survival in mice when presented as a neoglycoconjugate. Within LNFPIII is the Lewisx trisaccharide, expressed by many helminth parasites. In humans, LNFPIII is found in human milk and also known as stage-specific embryonic antigen-1. LNFPIII-NGC drives alternative activation of macrophages and dendritic cells via NFκB activation in a TLR4 dependent mechanism. However, the connection between LNFPIII-NGC activation of APCs, TLR4 signaling and subsequent MAP kinase signaling leading to anti-inflammatory activation of APCs remains unknown. In this study we determined that the innate receptor CD14 was essential for LNFPIII-NGC induction of both ERK and NFkB activation in APCs. Induction of ERK activation by LNFPIII-NGC was completely dependent on CD14/TLR4-Ras-Raf1/TPL2-MEK axis in bone marrow derived dendritic cells (BMDCs. In addition, LNFPIII-NGC preferentially induced the production of Th2 "favoring" chemokines CCL22 and matrix metalloprotease protein-9 in a CD14 dependent manner in BMDCs. In contrast, LNFPIII-NGC induces significantly lower levels of Th1 "favoring" chemokines, MIP1α, MIP1β and MIP-2 compared to levels in LPS stimulated cells. Interestingly, NGC of the identical human milk sugar LNnT, minus the alpha 1-3 linked fucose, failed to activate APCs via TLR4/MD2/CD14 receptor complex, suggesting that the alpha 1-3 linked fucose in LNFPIII and not on LNnT, is required for this process. Using specific chemical inhibitors of the MAPK pathway, we found that LNFPIII-NGC induction of CCL22, MMP9 and IL-10 production was dependent on ERK activation. Over all, this study suggests that LNFPIII-NGC utilizes CD14/TLR4-MAPK (ERK axis in modulating APC activation to produce anti-inflammatory chemokines and cytokines in a manner distinct from that seen for the pro-inflammatory PAMP LPS. These pathways may explain the in vivo

  20. Treponema pallidum (syphilis) antigen TpF1 induces angiogenesis through the activation of the IL-8 pathway

    Tommaso Pozzobon; Nicola Facchinello; Fleur Bossi; Nagaja Capitani; Marisa Benagiano; Giulietta Di Benedetto; Cristina Zennaro; Nicole West; Gaia Codolo; Marialina Bernardini; Cosima Tatiana Baldari; Mario Milco D’Elios; Luca Pellegrini; Francesco Argenton; Marina de Bernard

    2016-01-01

    Over 10 million people every year become infected by Treponema pallidum and develop syphilis, a disease with broad symptomatology that, due to the difficulty to eradicate the pathogen from the highly vascularized secondary sites of infection, is still treated with injections of penicillin. Unlike most other bacterial pathogens, T. pallidum infection produces indeed a strong angiogenic response whose mechanism of activation, however, remains unknown. Here, we report that one of the major antig...

  1. Association of Single Nucleotide Polymorphisms in the ST3GAL4 Gene with VWF Antigen and Factor VIII Activity.

    Song, Jaewoo; Xue, Cheng; Preisser, John S; Cramer, Drake W; Houck, Katie L; Liu, Guo; Folsom, Aaron R; Couper, David; Yu, Fuli; Dong, Jing-Fei

    2016-01-01

    VWF is extensively glycosylated with biantennary core fucosylated glycans. Most N-linked and O-linked glycans on VWF are sialylated. FVIII is also glycosylated, with a glycan structure similar to that of VWF. ST3GAL sialyltransferases catalyze the transfer of sialic acids in the α2,3 linkage to termini of N- and O-glycans. This sialic acid modification is critical for VWF synthesis and activity. We analyzed genetic and phenotypic data from the Atherosclerosis Risk in Communities (ARIC) study for the association of single nucleotide polymorphisms (SNPs) in the ST3GAL4 gene with plasma VWF levels and FVIII activity in 12,117 subjects. We also analyzed ST3GAL4 SNPs found in 2,535 subjects of 26 ethnicities from the 1000 Genomes (1000G) project for ethnic diversity, SNP imputation, and ST3GAL4 haplotypes. We identified 14 and 1,714 ST3GAL4 variants in the ARIC GWAS and 1000G databases respectively, with 46% being ethnically diverse in their allele frequencies. Among the 14 ST3GAL4 SNPs found in ARIC GWAS, the intronic rs2186717, rs7928391, and rs11220465 were associated with VWF levels and with FVIII activity after adjustment for age, BMI, hypertension, diabetes, ever-smoking status, and ABO. This study illustrates the power of next-generation sequencing in the discovery of new genetic variants and a significant ethnic diversity in the ST3GAL4 gene. We discuss potential mechanisms through which these intronic SNPs regulate ST3GAL4 biosynthesis and the activity that affects VWF and FVIII. PMID:27584569

  2. Analysis of antigen-specific, Ig-restricted cell-free material made by I-J+ Ly-1 cells (Ly-1 TsiF) that induces Ly-2+ cells to express suppressive activity.

    Yamauchi, K; Murphy, D; Cantor, H; Gershon, R K

    1981-11-01

    A set of T cells defined by a unique profile of cell surface alloantigens (phenotype Ly-1+2-; Qa-1+; I-J+) produces biologically active cell-free material(s) (Ly-1 TsiF) which induces another T cell set (cell surface phenotype Ly-1,2+; I-J/; Qa-1+) to participate in the suppression of primary immune responses to heterologous erythrocytes. The suppression is specific for the inducing antigen, and the Ly-1 TsiF binds antigen in a specific way. The activity of Ly-1 TsiF can be removed by anti-I-J immunosorbents and will not be expressed if the functional producer and acceptor cells do not share gene products that are encoded in or are tightly linked to the VH portion of the Ig complex. There is no requirement for the Ly-1 TsiF and its acceptor cell(s) to share major histocompatibility complex gene products. Thus, for optimal induction of antigen-specific suppression by cell-gree materials from Ly-1 T cells, three necessary conditions must be met: (a) antigen recognition by Ly-1 TsiF; (b) the expression of I-J gene products and (c) identify of VH-linked Ig locus gene products (or other products influenced by those genes) on both the inducer molecule and its acceptor cell. The role of the Ig-linked restriction is particularly intriguing, and its possible meaning is considered in detail. PMID:6173228

  3. DNA-based vaccination induces humoral and cellular immune responses against hepatitis B virus surface antigen in mice without activation of Cmyc

    Lian San Zhao; Shan Qin; Tao You Zhou; Hong Tang; Li Liu; Bing Jun Lei

    2000-01-01

    AIM To develop a safe and effective DNA vaccine for inducing humoral and cellular immunological responses against hepatitis B virus surface antigen (HBsAg). METHODS BALB/c mice were inoculated with NV-HB/s, a recombinant plasmid that had been inserted S gene of hepatitis B virus genome and could express HBsAg in eukaryotes. HBsAg expression was measured by ABC immunohistochemical assay, generation of anti-HBs by ELISA and cytotoxic T lymphocyte (CTL), by MTT method, existence of vaccine DNA by Southern blot hybridization and activation of oncogene C-myc by in situ hybridization.RESULTS With NV-HB/s vaccination by intramuscular injection, anti-HBs was initially positive 2 weeks after inoculation while all mice tested were HBsAg positive in the muscles. The titers and seroconversion rate of anti-HBs were steadily increasing as time went on and were dose-dependent. All the mice inoculated with 100 μg NV-HB/ s were anti-HBs positive one month after inoculation, the titer was 1:1024 or more. The humoral immune response was similar induced by either intramuscular or intradermal injection. CTL activities were much stronger (45.26%) in NV-HB/s DNA immunized mice as compared with those (only 6%) in plasmaderived HBsAg vaccine immunized mice. Two months after inoculation, all muscle samples were positive by Southern-blot hybridization for NV-HB/s DNA detection, but decreased to 25%and all were undetectable by in situ hybridization after 6 months. No oncogene Cmyc activation was found in the muscle of inoculation site. CONCLUSION NV-HB/s could generate humoral and cellular immunological responses against HBsAg that had been safely expressed in situ by NV-HB/s vaccination.

  4. Combined effects of 5-Fluorouracil, Folinic acid and Oxaliplatin on the expression of carcinoembryonic antigen in human colon cancer cells: pharmacological basis to develop an active antitumor immunochemotherapy

    De Vecchis Liana

    2008-05-01

    Full Text Available Abstract Background Five-fluorouracil (FU, mainly associated with leucovorin (L, plays an essential role in chemotherapy of colorectal carcinoma. Moreover, FU ± L has been found to increase the expression of tumor-associated carcinoembryonic antigen (CEA, that may be an important target in therapeutic protocols of active specific immunotherapy. FU + L (FUL are frequently combined with oxaliplatin (OXA in advanced colon cancer patients. Thus, we investigated whether FUL in combination with OXA according to 2 different schedules may influence CEA expression in human colon cancer cells in vitro. Methods CEA protein expression was evaluated by cytofluorimetric and western blot analysis. Relative quantification of CEA mRNA was assessed by real time RT-PCR analysis. Results Levels of CEA protein and transcript were found to be higher in FUL-treated cells than in controls. However, when target cells were exposed to OXA before but not after FUL treatment, the up-regulation of CEA was partially inhibited. Conclusion These results suggest that target cells must be exposed to OXA after but not before treatment with the fluoropyrimidine in order to exploit drug-induced up-regulation of CEA. This finding appears to provide useful information to design chemo-immunotherapy protocols based on FUL + OXA, combined with host's immunity against CEA directed cancer vaccines.

  5. Dietary fish oil and DHA down-regulate antigen-activated CD4+ T-cells while promoting the formation of liquid-ordered mesodomains.

    Kim, Wooki; Barhoumi, Rola; McMurray, David N; Chapkin, Robert S

    2014-01-28

    We have demonstrated previously that n-3 PUFA endogenously produced by fat-1 transgenic mice regulate CD4+ T-cell function by affecting the formation of lipid rafts, liquid-ordered mesodomains in the plasma membrane. In the present study, we tested the effects of dietary sources of n-3 PUFA, i.e. fish oil (FO) or purified DHA, when compared with an n-6 PUFA-enriched maize oil control diet in DO11.10 T-cell receptor transgenic mice. Dietary n-3 PUFA were enriched in CD4+ T-cells, resulting in the increase of the n-3:n-6 ratio. Following antigen-specific CD4+ T-cell activation by B-lymphoma cells pulsed with the ovalbumin 323-339 peptide, the formation of liquid-ordered mesodomains at the immunological synapse relative to the whole CD4+ T-cell, as assessed by Laurdan labelling, was increased (P< 0·05) in the FO-fed group. The FO diet also suppressed (P< 0·05) the co-localisation of PKCθ with ganglioside GM1 (monosialotetrahexosylganglioside), a marker for lipid rafts, which is consistent with previous observations. In contrast, the DHA diet down-regulated (P< 0·05) PKCθ signalling by moderately affecting the membrane liquid order at the immunological synapse, suggesting the potential contribution of the other major n-3 PUFA components of FO, including EPA. PMID:23962659

  6. Growth delay of human bladder cancer cells by Prostate Stem Cell Antigen downregulation is associated with activation of immune signaling pathways

    Prostate stem cell antigen (PSCA) is a glycosylphosphatidylinositol (GPI) anchored protein expressed not only in prostate but also in pancreas and bladder cancer as shown by immunohistochemistry and mRNA analysis. It has been targeted by monoclonal antibodies in preclinical animal models and more recently in a clinical trial in prostate cancer patients. The biological role played in tumor growth is presently unknown. In this report we have characterized the contribution of PSCA expression to tumor growth. A bladder cell line was engineered to express a doxycycline (dox) regulated shRNA against PSCA. To shed light on the PSCA biological role in tumor growth, microarray analysis was carried out as a function of PSCA expression. Expression of gene set of interest was further analyzed by qPCR Down regulation of the PSCA expression was associated with reduced cell proliferation in vitro and in vivo. Mice bearing subcutaneous tumors showed a reduced tumor growth upon treatment with dox, which effectively induced shRNA against PSCA as revealed by GFP expression. Pathway analysis of deregulated genes suggests a statistical significant association between PSCA downregulation and activation of genes downstream of the IFNα/β receptor. These experiments established for the first time a correlation between the level of PSCA expression and tumor growth and suggest a role of PSCA in counteracting the natural immune response

  7. The carboxyl-terminal domain of large T antigen rescues SV40 host range activity in trans independent of acetylation.

    Poulin, Danielle L; DeCaprio, James A

    2006-05-25

    The host range activity of SV40 has been described as the inability of mutant viruses with deletions in the C terminal region of large T Ag to replicate in certain types of African green monkey kidney cells. We constructed new mutant viruses expressing truncated T Ag proteins and found that these mutant viruses exhibited the host range phenotype. The host range phenotype was independent of acetylation of T Ag at lysine 697. Co-expression of the C terminal domain of T Ag (aa 627-708) in trans increased both T Ag and VP1 mRNA as well as protein levels for host range mutant viruses in the restrictive cell type. In addition, the T Ag 627-708 fragment promoted the productive lytic infection of host range mutant viruses in the nonpermissive cell type. The carboxyl-terminal region of T Ag contains a biological function essential for the SV40 viral life cycle. PMID:16510165

  8. Antitumor activities of dFv-LDP-AE: An enediyne-energized fusion protein targeting tumor-associated antigen gelatinases.

    Zhong, Gen-Shen; Wu, Min-Na; Guo, Xiao-Fang; Zhang, Sheng-Hua; Miao, Qing-Fang; Zhen, Yong-Su

    2012-10-01

    Gelatinases play an important role in tumor growth and metastasis, and overexpression of these molecules is strongly correlated with poor prognosis in a variety of malignant tumors. Lidamycin is an enediyne antitumor antibiotic with potent cytotoxicity. We previously reported that a tandem scFv format (dFv-LDP-AE) showed enhanced binding ability with gelatinases compared with the scFv-lidamycin conjugate (Fv-LDP-AE). In this study, the antitumor activities of dFv-LDP-AE on hepatocellular carcinoma (HCC) were evaluated in vitro and in vivo. By SDS-PAGE analysis, it was found that partial fusion protein dFv-LDP existed as dimer; the results of ELISA and immunofluorescence demonstrated that the fusion protein dFv-LDP could efficiently bind to hepatoma cells in vitro. The apparent arrest of cell cycle at G2/M phase and induction of apoptosis at nanomole levels indicated that the dFv-LDP-AE was very potent against HCC. In in vivo experiments, dFv-LDP-AE shown enhanced cytotoxic effects compared to those of LDM. Administration at mouse tolerable dosage level, the inhibition rate of tumor growth was 89.5% of dFv-LDP-AE vs. 73.6% of LDM on transplantable H22 in mice (Penediyne-energized fusion protein dFv-LDP-AE showed potential application as a new agent for therapeutic appications in HCC. PMID:22797730

  9. Plasmids enriched with CpG motifs activate human peripheral blood mononuclear cells in vitro and enhance th-1 immune responses to hepatitis B surface antigen in mice.

    Chen, Zhihui; Cao, Jie; Liao, Xiaoling; Ke, Jinshan; Zhu, Shiying; Zhao, Ping; Qi, Zhongtian

    2011-06-01

    T helper-1 (Th-1)-type immune responses play an important role in viral clearance during infection with hepatitis B virus (HBV). Unmethylated CpG motifs present in bacterial DNA can activate toll-like receptor 9 (TLR9) signals and act as potent adjuvants to induce Th-1-type immune responses. Here, a mini-plasmid with 812 base pairs in length was constructed and used as a vector to prepare a series of plasmids containing 3-21 copies of D-type CpG motifs. In vitro, these CpG-enriched plasmids strongly stimulated proliferation of human peripheral blood mononuclear cells (PBMCs) and enhanced secretion of interferon-γ (IFN-γ) and interleukin-12 (IL-12). The responses of the PBMCs from healthy individuals to the plasmids were stronger than those obtained from HBV-infected individuals. Contrary to the strong Th-2-biased response induced by surface antigen of hepatitis B virus (HBsAg) plus alum adjuvant, immunization of BALB/c mice with HBsAg plus these plasmids induced a strong Th-1-biased response. The plasmids increased the titers of HBsAg-specific total immunoglobulin G (IgG) and IgG(2a). HBsAg-specific IL-2 and IFN-γ production and cytotoxic activity were also enhanced in the presence of the plasmids. The strength of the immune responses positively correlated with the number of CpG motifs in the plasmids. These results indicate that the use of CpG-enriched plasmids as an adjuvant to recombinant HBsAg could provide a promising and cost-effective approach for the development of efficacious therapeutic vaccines against HBV infection. PMID:21668361

  10. Expression of an antigen homologous to the human CO17-1A/GA733 colon cancer antigen in animal tissues.

    Zaloudik, J; Basak, S.; Nesbit, M.; Speicher, D W; Wunner, W H; Miller, E.; Ernst-Grotkowski, C.; Kennedy, R; Bergsagel, L. P.; Koido, T.; Herlyn, D

    1997-01-01

    The CO17-1A/GA733 antigen is associated with human carcinomas and some normal epithelial tissues. This antigen has shown promise as a target in approaches to passive and active immunotherapy of colorectal cancer. The relevance of animal models for studies of immunotherapy targeting this antigen in patients is dependent on the expression of the antigen on normal animal tissues. Immunohistoperoxidase staining with polyclonal rabbit antibodies to the human antigen revealed the human homologue on...

  11. Separation of uncompromised whole blood mixtures for single source STR profiling using fluorescently-labeled human leukocyte antigen (HLA) probes and fluorescence activated cell sorting (FACS).

    Dean, Lee; Kwon, Ye Jin; Philpott, M Katherine; Stanciu, Cristina E; Seashols-Williams, Sarah J; Dawson Cruz, Tracey; Sturgill, Jamie; Ehrhardt, Christopher J

    2015-07-01

    Analysis of biological mixtures is a significant problem for forensic laboratories, particularly when the mixture contains only one cell type. Contributions from multiple individuals to biologic evidence can complicate DNA profile interpretation and often lead to a reduction in the probative value of DNA evidence or worse, its total loss. To address this, we have utilized an analytical technique that exploits the intrinsic immunological variation among individuals to physically separate cells from different sources in a mixture prior to DNA profiling. Specifically, we applied a fluorescently labeled antibody probe to selectively bind to one contributor in a mixture through allele-specific interactions with human leukocyte antigen (HLA) proteins that are expressed on the surfaces of most nucleated cells. Once the contributor's cells were bound to the probe, they were isolated from the mixture using fluorescence activated cell sorting (FACS)-a high throughput technique for separating cell populations based on their optical properties-and then subjected to STR analysis. We tested this approach on two-person and four-person whole blood mixtures where one contributor possessed an HLA allele (A*02) that was not shared by other contributors to the mixture. Results showed that hybridization of the mixture with a fluorescently-labeled antibody probe complimentary to the A*02 allele's protein product created a cell population with a distinct optical profile that could be easily differentiated from other cells in the mixture. After sorting the cells with FACS, genetic analysis showed that the STR profile of this cell population was consistent with that of the contributor who possessed the A*02 allele. Minor peaks from the A*02 negative contributor(s) were observed but could be easily distinguished from the profile generated from A*02 positive cells. Overall, this indicates that HLA antibody probes coupled to FACS may be an effective approach for generating STR profiles of

  12. Immunoassay for phenylurea herbicides: application of molecular modeling and quantitative structure-activity relationship analysis on an antigen-antibody interaction study.

    Yuan, Meng; Liu, Bing; Liu, Enmei; Sheng, Wei; Zhang, Yan; Crossan, Angus; Kennedy, Ivan; Wang, Shuo

    2011-06-15

    An indirect competitive enzyme-linked immunosorbent assay (icELISA) for 12 phenylurea herbicides (PUHs) was established with the half-maximum inhibition concentration (IC(50)) of 1.7-920.7 μg L(-1). A method of computer-aided molecular modeling was established in quantitative structure-activity relationship (QSAR) studies to obtain a deeper insight into the PUHs' antibody interactions on how and which molecular properties of the analytes quantitatively affect the antibody recognition. A two-dimensional (2D)-QSAR model based on the Hansch equation and a hologram QSAR (HQSAR) model were constructed, and both showed highly predictive abilities with cross-validation q(2) values of 0.820 and 0.752, respectively. It was revealed that the most important impact factor of the antibody recognition was the PUHs' hydrophobicity (log P), which provided a quadratic correlation to the antibody recognition. Hapten-carrier linking groups were less exposed to antibodies during immunization; thus, groups of the analytes in the same position were generally considered to be less contributive to antibody recognition during immunoassay. But the results of substructure-level analysis showed that these groups played an important role in the antigen-antibody interaction. In addition, the frontier-orbital energy parameter E(LUMO) was also demonstrated as a related determinant for this reaction. In short, the result demonstrated that the hydrophobicity and the lowest unoccupied molecular orbital energy (E(LUMO)) of PUH molecules were mainly responsible for antibody recognition. PMID:21539295

  13. Immunization with antigenic peptides complexed with β-glucan induces potent cytotoxic T-lymphocyte activity in combination with CpG-ODNs.

    Mochizuki, Shinichi; Morishita, Hiromi; Kobiyama, Kouji; Aoshi, Taiki; Ishii, Ken J; Sakurai, Kazuo

    2015-12-28

    The induction of antigen-specific immune responses requires immunization with not only antigens, but also adjuvants. CpG oligonucleotides (CpG-ODNs) are well-known ligands for Toll-like receptor 9 and a potent adjuvant that induces both Th1-type humoral and cellular immune responses including cytotoxic T-lymphocyte responses. We previously demonstrated that β-glucan schizophyllan (SPG) can form complexes with CpG-ODNs with attached dA40 (CpG-dA/SPG), which can accumulate in macrophages in the draining inguinal lymph nodes and induce strong immune responses by co-administration of antigenic proteins, namely ovalbumin (OVA). Immunization with antigenic peptides, OVA257-264, did not induce these antigen-specific immune responses even in combination with CpG-dA/SPG, indicating that peptides require a carrier to antigen presenting cells. In this study, we prepared conjugates comprising OVA257-264 and dA40, and made complexes with SPG. Immunization with OVA257-264-dA/SPG induced peptide-specific immune responses in combination with CpG-dA regardless of complexation with SPG both in vitro and in vivo. When splenocytes from immunized mice were incubated with E.G7-OVA tumor model cells presenting OVA peptides, the number of cells drastically decreased after 24h. Furthermore, mice pre-immunized with OVA257-264-dA/SPG and CpG-ODNs exhibited a long delay in tumor growth after tumor inoculation. Therefore, these peptide-dA/SPG and CpG-dA/SPG complexes could be used as a potent vaccine for the treatment of cancers and infectious diseases. PMID:26562685

  14. CD85/LIR-1/ILT2 and CD152 (cytotoxic T lymphocyte antigen 4) inhibitory molecules down-regulate the cytolytic activity of human CD4+ T-cell clones specific for Mycobacterium tuberculosis.

    Merlo, A; Saverino, D; Tenca, C; Grossi, C E; Bruno, S; Ciccone, E

    2001-10-01

    Antigen-specific cytolytic CD4+ T lymphocytes control Mycobacterium tuberculosis infection by secreting cytokines and by killing macrophages that have phagocytosed the pathogen. However, lysis of the latter cells promotes microbial dissemination, and other macrophages engulf the released bacteria. Subsequently, CD4+ T-cell-mediated killing of macrophages goes on, and this persistent process may hamper control of infection, unless regulatory mechanisms maintain a subtle balance between lysis of macrophages by cytolytic CD4+ cells and activation of cytolytic CD4+ cells by infected macrophages. We asked whether inhibitory molecules expressed by CD4+ cytolytic T lymphocytes could play a role in such a balance. To this end, human CD4+ T-cell clones specific for M. tuberculosis were produced that displayed an autologous major histocompatibility complex class II-restricted lytic ability against purified protein derivative (PPD)-pulsed antigen-presenting cells. All T-cell clones expressed CD152 (cytotoxic T-lymphocyte antigen 4 [CTLA-4]) and CD85/leukocyte immunoglobulin-like receptor 1 (LIR-1)/immunoglobulin-like transcript 2 (ILT2) inhibitory receptors, but not CD94 and the killer inhibitory receptor (or killer immunoglobulin-like receptor [KIR]) p58.2. CD3-mediated activation of the clones was inhibited in a redirected killing assay in which CD152 and CD85/LIR-1/ILT2 were cross-linked. Specific antigen-mediated proliferation of the clones was also sharply reduced when CD152 and CD85/LIR-1/ILT2 were cross-linked by specific monoclonal antibody (MAb) followed by goat anti-mouse antiserum. In contrast, blockade of the receptors by specific MAb only increased their proliferation. Production of interleukin 2 (IL-2) and gamma interferon (IFN-gamma) by the T-cell clones was also strongly reduced when CD152 and CD85/LIR-1/ILT2 were cross-linked. The lytic activity of the T-cell clones against PPD-pulsed autologous monocytes or Epstein-Barr virus-activated B cells was increased

  15. A liquid crystal of ascorbyl palmitate, used as vaccine platform, provides sustained release of antigen and has intrinsic pro-inflammatory and adjuvant activities which are dependent on MyD88 adaptor protein.

    Sánchez Vallecillo, María F; Minguito de la Escalera, María M; Aguirre, María V; Ullio Gamboa, Gabriela V; Palma, Santiago D; González-Cintado, Leticia; Chiodetti, Ana L; Soldano, Germán; Morón, Gabriel; Allemandi, Daniel A; Ardavín, Carlos; Pistoresi-Palencia, María C; Maletto, Belkys A

    2015-09-28

    Modern subunit vaccines require the development of new adjuvant strategies. Recently, we showed that CpG-ODN formulated with a liquid crystal nanostructure formed by self-assembly of 6-O-ascorbyl palmitate (Coa-ASC16) is an attractive system for promoting an antigen-specific immune response to weak antigens. Here, we showed that after subcutaneous injection of mice with near-infrared fluorescent dye-labeled OVA antigen formulated with Coa-ASC16, the dye-OVA was retained at the injection site for a longer period than when soluble dye-OVA was administered. Coa-ASC16 alone elicited a local inflammation, but how this material triggers this response has not been described yet. Although it is known that some materials used as a platform are not immunologically inert, very few studies have directly focused on this topic. In this study, we explored the underlying mechanisms concerning the interaction between Coa-ASC16 and the immune system and we found that the whole inflammatory response elicited by Coa-ASC16 (leukocyte recruitment and IL-1β, IL-6 and IL-12 production) was dependent on the MyD88 protein. TLR2, TLR4, TLR7 and NLRP3-inflammasome signaling were not required for induction of this inflammatory response. Coa-ASC16 induced local release of self-DNA, and in TLR9-deficient mice IL-6 production was absent. In addition, Coa-ASC16 revealed an intrinsic adjuvant activity which was affected by MyD88 and IL-6 absence. Taken together these results indicate that Coa-ASC16 used as a vaccine platform is effective due to the combination of the controlled release of antigen and its intrinsic pro-inflammatory activity. Understanding how Coa-ASC16 works might have significant implications for rational vaccine design. PMID:26188153

  16. Relationship of spermatoscopy, prostatic acid phosphatase activity and prostate-specific antigen (p30) assays with further DNA typing in forensic samples from rape cases.

    Romero-Montoya, Lydia; Martínez-Rodríguez, Hugo; Pérez, Miguel Antonio; Argüello-García, Raúl

    2011-03-20

    In the forensic laboratory the biological analyses for rape investigation commonly include vaginal swabs as sample material combined to biochemical tests including sperm cytology (SC) and detection of acid phosphatase activity (AP) and prostate-specific antigen (PSA, p30) for the conclusive identification of semen components. Most reports comparing these tests relied on analysis of semen samples or donor swabs taken under controlled conditions; however their individual or combined efficacy under real live sampling conditions in different laboratories is largely unknown. We carried out SC, APA and PSA analyses in vaginal swabs collected from casework rapes submitted to Mexican Forensic Laboratories at Texcoco and Toluca. On the basis of positive and negative results from each assay and sample, data were classified into eight categories (I-VIII) and compared with those obtained in the two only similar studies reported in Toronto, Canada and Hong Kong, China. SC and APA assays had the higher overall positivity in Toluca and Texcoco samples respectively and otherwise PSA had a lower but very similar positivity between these two laboratories. When compared to the previous studies some similarities were found, namely similar frequencies (at a ratio of approximately 1 out of 3) of samples being positive or negative by all techniques (Categories I and VI respectively) and a comparable overall positivity of APA and SC but higher than that of PSA. Indeed the combined results of using SC, APA and PSA tests was considered as conclusive for semen detection from approximately 1 out of 3 cases (Category I) to approximately 1 out of 2 cases in a scenario where at least SC is positive, strongly presumptive in 2 out of 3 cases (with at least one test positive) and the remainder 1 out of 3 cases (Category VI) suggested absence of semen. By determining Y-STR polymorphisms (12-loci) in additional samples obtained at Toluca laboratory, complete DNA profiles were determined from all

  17. COMPARISON OF EXCRETORY SECRETORY ANTIGENS OF ASCARIS LUMBRICOLDES AND TOXOCARA CATI 2ND. STAGE LARVAE WITH BIOCHEMICAL METHODES

    F. Maleky; Massoud, J.

    1995-01-01

    Purification of parasitic antigens is a major activity in immunoparasitology because of its application in immunodiagnosis, vaccination analysis of immunopathology, preparation of monocolomal antibody and finding out the cross reactive antigens versus specific antigens of a parasite. In this survey F2 ultrafiltration excretory secretory antigens of Ascaris lumbricoides and Toxocara cati were separated by gel chromatography on sephacryl S-200 into several antigenic and non antigenic fractions....

  18. Wegener's granulomatosis and autoantibodies to neutrophil antigens

    McCluskey, D R; Maxwell, A. P.; Watt, L

    1988-01-01

    We report five cases of Wegener's granulomatosis all of whom had clinical and histological evidence of disease activity at presentation and in whom autoantibodies to neutrophil antigens were detected. This test may prove useful for the diagnosis of this serious condition and help to monitor disease activity during treatment.

  19. Common acute lymphoblastic leukemia antigen (CALLA) is active neutral endopeptidase 24.11 ("enkephalinase"): direct evidence by cDNA transfection analysis.

    Shipp, M A; Vijayaraghavan, J.; Schmidt, E V; Masteller, E L; D'Adamio, L; Hersh, L.B.; Reinherz, E L

    1989-01-01

    The common acute lymphoblastic leukemia antigen (CALLA) is a 749-amino acid type II integral membrane protein expressed by most acute lymphoblastic leukemias, certain other lymphoid malignancies with an immature phenotype, and normal lymphoid progenitors. A computer search against the most recent GenBank release (no. 56) indicates that human CALLA cDNA encodes a protein nearly identical to the rat and rabbit neutral endopeptidase 24.11 ("enkephalinase;" EC 3.4.24.11). This zinc metalloendopep...

  20. Novel selective inhibitors of aminopeptidases that generate antigenic peptides.

    Papakyriakou, Athanasios; Zervoudi, Efthalia; Theodorakis, Emmanuel A; Saveanu, Loredana; Stratikos, Efstratios; Vourloumis, Dionisios

    2013-09-01

    Endoplasmic reticulum aminopeptidases, ERAP1 and ERAP2, as well as Insulin regulated aminopeptidase (IRAP) play key roles in antigen processing, and have recently emerged as biologically important targets for manipulation of antigen presentation. Taking advantage of the available structural and substrate-selectivity data for these enzymes, we have rationally designed a new series of inhibitors that display low micromolar activity. The selectivity profile for these three highly homologous aminopeptidases provides a promising avenue for modulating intracellular antigen processing. PMID:23916253

  1. Production of soluble recombinant proteins with Kell, Duffy and Lutheran blood group antigen activity, and their use in screening human sera for Kell, Duffy and Lutheran antibodies.

    Ridgwell, K; Dixey, J; Scott, M L

    2007-10-01

    The aim of this study was to show that soluble recombinant (sr) proteins can mimic blood group antigens and be used to screen human sera for blood-group-specific antibodies. The blood of all pregnant women and pretransfusion patients should be screened for blood-group-specific antibodies to identify and monitor pregnancies at risk of haemolytic disease of the foetus and newborn (HDFN), and to prevent haemolytic transfusion reactions. Current antibody screening and identification methods use human red blood cell panels, which can complicate antibody identification if more than one antibody specificity is present. COS-7 cells were transfected to produce sr forms of the extracellular domains of the red blood cell membrane proteins that express Kell, Duffy or Lutheran blood group antigens. These sr proteins were used to screen for and identify anti-Kell, anti-Duffy or anti-Lutheran blood-group-specific allo-antibodies in human sera by haemagglutination inhibition and in solid-phase enzyme-linked immunosorbent assays (ELISAs). There is a positive correlation (correlation coefficient 0.605, P value 0.002) between antibody titre by standard indirect antiglobulin test (IAT) and signal intensity in the ELISA test. This work shows that sr proteins can mimic blood group antigens and react with human allogeneic antibodies, and that such proteins could be used to develop solid-phase, high-throughput blood group antibody screening and identification platforms. PMID:17725551

  2. Immunochemical properties of antigen-specific monkey T-cell suppressor factor induced with a Streptococcus mutans antigen.

    Lamb, J R; Zanders, E D; Kontiainen, S; Lehner, T.

    1980-01-01

    Antigen-specific suppressor factor could be released from monkey suppressor T cells induced in vitro with a protein antigen isolated from the carcinogenic bacterium Streptococcus mutans. The suppressor activity was due to the factor itself and not to carryover of free antigen. Characterization of the monkey factor revealed it to have a molecular weight of ca. 70,000, and to contain a constant region and determinants encoded by the major histocompatibility complex. The presence of immunoglobul...

  3. Cancer vaccine--Antigenics.

    2002-01-01

    Antigenics is developing a therapeutic cancer vaccine based on heat-shock proteins (HSPs). The vaccine [HSPPC-96, Oncophage] is in a pivotal phase III clinical trial for renal cancer at 80 clinical sites worldwide. The trial is enrolling at least 500 patients who are randomised to receive surgical removal of the primary tumour followed by out-patient treatment with Oncophage((R)) or surgery only. This study was initiated on the basis of results from a pilot phase I/II study and preliminary results from a phase II study in patients with renal cell cancer. In October 2001, Oncophage was designated as a fast-track product by the Food and Drug Administration in the US for the treatment of renal cell carcinoma. Oncophage is in phase I/II trials in Italy for colorectal cancer (30 patients) and melanoma. The trials in Italy are being conducted at the Istituto dei Tumouri, Milan (in association with Sigma-Tau). Preliminary data from the phase II trial for melanoma was presented at the AACR-NCI-EORTC International Conference in Florida, USA, in October 2001. Oncophage is also in a phase I/II (42 patients) and a phase II trial (84 patients) in the US for renal cell cancer, a phase II trial in the US for non-Hodgkin's lymphoma (35 patients), a phase II trial in the US for sarcoma (20-35 patients), a phase I/II trial in the US for melanoma (36 patients), and phase I/II trials in Germany for gastric (30 patients) and pancreatic cancers. A pilot phase I trial in patients with pancreatic cancer began in the US in 1997 with 5 patients enrolled. In November 2000, Antigenics announced that this trial had been expanded to a phase I/II study which would now include survival as an endpoint and would enroll 5 additional patients. The US trials are being performed at Memorial Sloan-Kettering Cancer Center and the M.D. Anderson Cancer Center. The trials in Germany are being carried out at Johannes Gutenberg-University Hospital, Mainz. Oncophage is an autologous vaccine consisting of

  4. A novel strategy for the development of selective active-site inhibitors of the protein tyrosine phosphatase-like proteins islet-cell antigen 512 (IA-2) and phogrin (IA-2 beta)

    Drake, P.G.; Peters, Günther H.j.; Andersen, H.S.;

    2003-01-01

    Islet-cell antigen 512 (IA-2) and phogrin (IA-2) are atypical members of he receptor protein tyrosine phosphatase (PTP) family that are characterized by a lack of activity against conventional PTP substrates. The physiological role(s) of these proteins remain poorly defined, although recent studies...... indicate that IA-2 may be involved in granule trafficking and exocytosis. To further 9 understand their function, we have embarked upon developing low-molecular-mass inhibitors of IA-2 and IA-2. Previously, we have shown that a general PTP inhibitor, 2-(oxalylamino)benzoic acid (OBA), can be developed into...

  5. Acute Lymphoid Leukemia Cells with Greater Stem Cell Antigen-1 (Ly6a/Sca-1) Expression Exhibit Higher Levels of Metalloproteinase Activity and Are More Aggressive In Vivo

    Yu-Chiao Hsu; Kurt Mildenstein; Kordell Hunter; Olena Tkachenko; Mullen, Craig A.

    2014-01-01

    Stem cell antigen-1 (Ly6a/Sca-1) is a gene that is expressed in activated lymphocytes, hematopoietic stem cells and stem cells of a variety of tissues in mice. Despite decades of study its functions remain poorly defined. These studies explored the impact of expression of this stem cell associated gene in acute lymphoid leukemia. Higher levels of Ly6a/Sca-1 expression led to more aggressive leukemia growth in vivo and earlier death of hosts. Leukemias expressing higher levels of Ly6a/Sca-1 ex...

  6. Binding of recombinant T cell receptor ligands (RTL) to antigen presenting cells prevents upregulation of CD11b and inhibits T cell activation and transfer of experimental autoimmune encephalomyelitis

    Sinha, Sushmita; Miller, Lisa; Subramanian, Sandhya; McCarty, Owen; Proctor, Thomas; Meza-Romero, Roberto; Burrows, Gregory G.; Vandenbark, Arthur A.; Offner, Halina

    2010-01-01

    Recombinant T cell ligands (RTLs) ameliorate experimental autoimmune encephalomyelitis (EAE) in antigen specific manner. We evaluated effects of RTL401 (I-As α1β1 + PLP-139-151) on splenocytes from mice with EAE to study RTL- T cell-tolerance-inducing mechanisms. RTLs bound to B, macrophages and DCs, through RTL-MHC-α1β1 moiety. RTL binding reduced CD11b expression on splenic macrophages/DC, and RTL401-conditioned macrophages/DC, not B cells, inhibited T cell activation. Reduced ability of RT...

  7. Beyond antigens and adjuvants: formulating future vaccines.

    Moyer, Tyson J; Zmolek, Andrew C; Irvine, Darrell J

    2016-03-01

    The need to optimize vaccine potency while minimizing toxicity in healthy recipients has motivated studies of the formulation of vaccines to control how, when, and where antigens and adjuvants encounter immune cells and other cells/tissues following administration. An effective subunit vaccine must traffic to lymph nodes (LNs), activate both the innate and adaptive arms of the immune system, and persist for a sufficient time to promote a mature immune response. Here, we review approaches to tailor these three aspects of vaccine function through optimized formulations. Traditional vaccine adjuvants activate innate immune cells, promote cell-mediated transport of antigen to lymphoid tissues, and promote antigen retention in LNs. Recent studies using nanoparticles and other lymphatic-targeting strategies suggest that direct targeting of antigens and adjuvant compounds to LNs can also enhance vaccine potency without sacrificing safety. The use of formulations to regulate biodistribution and promote antigen and inflammatory cue co-uptake in immune cells may be important for next-generation molecular adjuvants. Finally, strategies to program vaccine kinetics through novel formulation and delivery strategies provide another means to enhance immune responses independent of the choice of adjuvant. These technologies offer the prospect of enhanced efficacy while maintaining high safety profiles necessary for successful vaccines. PMID:26928033

  8. T-antigen binding lectin with antibacterial activity from marine invertebrate, sea cucumber (Holothuria scabra): Possible involvement in differential recognition of bacteria

    Gowda, N.M.; Goswami, U.; Khan, M.I.

    erythrocytes of all human blood groups. It is highly stable at high temperature and under wider pH range. HSL is T-antigen specific, can distinguish a- from b-anomers (Gowda et al., 2008). In this article, we report our studies on induction of HSL upon...) involved in immune response brate Pathology sevier.com/locate/yjipa Human erythrocytes of blood group A, B and O were washed 4– 5 times with 20 mM Tris–HCl buffer pH 7.2 containing 150 mM NaCl (TBS) and a final suspension of 3% (v/v) was prepared in TBS...

  9. Simian virus 40 T antigen can transcriptionally activate and mediate viral DNA replication in cells which lack the retinoblastoma susceptibility gene product.

    Trifillis, P; Picardi, J; Alwine, J C

    1990-01-01

    Simian virus 40 T antigen is a multifunctional protein which has recently been shown to form a complex with the retinoblastoma susceptibility gene product (Rb protein) (J.A. DeCaprio, J.W. Ludlow, J. Figge, J.-Y. Shaw, C.-M. Huang, W.-H. Lee, E. Marsilio, E. Paucha, and D.M. Livingston, Cell 54:275-283, 1988; P. Whyte, K.J. Buchkovich, J.M. Horowitz, S.H. Friend, M. Raybuck, R.A. Weinberg, and E. Harlow, Nature (London) 334:124-129, 1988). This interaction may facilitate some of the functions...

  10. The Latency-Associated Nuclear Antigen of Rhesus Monkey Rhadinovirus Inhibits Viral Replication through Repression of Orf50/Rta Transcriptional Activation

    DeWire, Scott M.; Damania, Blossom

    2005-01-01

    Rhesus monkey rhadinovirus (RRV) is a gamma-2-herpesvirus that is closely related to Kaposi's sarcoma-associated herpesvirus/human herpesvirus-8. We have previously reported that the transcript for RRV latency-associated nuclear antigen (R-LANA) is expressed during lytic replication in rhesus fibroblasts. In this article, we report the development of a latent culture system for RRV and show that mRNA specific for R-LANA is expressed during latency as well. We have characterized the R-LANA pro...

  11. Antigen detection systems

    Infectious agents or their constituent parts (antigens or nucleic acids) can be detected in fresh, frozen, or fixed tissues or other specimens, using a variety of direct or indirect assays. The assays can be modified to yield the greatest sensitivity and specificity but in most cases a particular m...

  12. Aspergillus antigen skin test (image)

    The aspergillus antigen skin test determines whether or not a person has been exposed to the mold aspergillus. It is performed by injecting an aspergillus antigen under the skin with a needle. After 48 ...

  13. L1 Cell Adhesion Molecule-Specific Chimeric Antigen Receptor-Redirected Human T Cells Exhibit Specific and Efficient Antitumor Activity against Human Ovarian Cancer in Mice.

    Hao Hong

    Full Text Available New therapeutic modalities are needed for ovarian cancer, the most lethal gynecologic malignancy. Recent clinical trials have demonstrated the impressive therapeutic potential of adoptive therapy using chimeric antigen receptor (CAR-redirected T cells to target hematological cancers, and emerging studies suggest a similar impact may be achieved for solid cancers. We sought determine whether genetically-modified T cells targeting the CE7-epitope of L1-CAM, a cell adhesion molecule aberrantly expressed in several cancers, have promise as an immunotherapy for ovarian cancer, first demonstrating that L1-CAM was highly over-expressed on a panel of ovarian cancer cell lines, primary ovarian tumor tissue specimens, and ascites-derived primary cancer cells. Human central memory derived T cells (TCM were then genetically modified to express an anti-L1-CAM CAR (CE7R, which directed effector function upon tumor antigen stimulation as assessed by in vitro cytokine secretion and cytotoxicity assays. We also found that CE7R+ T cells were able to target primary ovarian cancer cells. Intraperitoneal (i.p. administration of CE7R+ TCM induced a significant regression of i.p. established SK-OV-3 xenograft tumors in mice, inhibited ascites formation, and conferred a significant survival advantage compared with control-treated animals. Taken together, these studies indicate that adoptive transfer of L1-CAM-specific CE7R+ T cells may offer a novel and effective immunotherapy strategy for advanced ovarian cancer.

  14. Stool Test: H. Pylori Antigen

    ... All About Food Allergies Stool Test: H. Pylori Antigen KidsHealth > For Parents > Stool Test: H. Pylori Antigen Print A A A Text Size What's in ... sample is used to determine if H. pylori antigens are present in your child's gastrointestinal (GI) system. ...

  15. H-Y antigen in transsexuality, and how to explain testis differentiation in H-Y antigen-negative males and ovary differentiation in H-Y antigen-positive females.

    Engel, W; Pfäfflin, F; Wiedeking, C

    1980-01-01

    H-Y antigen was determined in eight transsexual patients. Two of the four male-to-female transsexual patients typed as H-Y antigen-negative, while the other two typed as expected from their phenotypic and gonadal sex, namely H-Y antigen-positive. Of the four female-to-male transsexual patients, three typed as H-Y antigen-positive and one was H-Y antigen-negative, as expected. The presence of normal testes in H-Y antigen-negative males is assumed to result from a mutation of nucleotide sequences of the H-Y structural gene for antigenic determinants. Thus, an H-Y is produced with normal receptor-binding activity which can sustain the testis determination of the bipotent gonadal anlage. In the case of H-Y antigen-positive females with normal ovaries a deletion of the autosomally located H-Y structural gene is assumed. This deletion should affect sequences for repressor-binding (as was suggested for H-Y antigen-positive XX-males) and for receptor-binding activity of the H-Y antigen molecule. The resulting H-Y antigen is unable to bind to the gonadal receptor of the bipotent gonadal anlage. Thus an ovary is determined. The relevance of H-Y antigen for the aetiology of transsexualism is discussed. PMID:7203464

  16. Heat Shock Enhances the Expression of the Human T Cell Leukemia Virus Type-I (HTLV-I) Trans-Activator (Tax) Antigen in Human HTLV-I Infected Primary and Cultured T Cells.

    Kunihiro, Marie; Fujii, Hideki; Miyagi, Takuya; Takahashi, Yoshiaki; Tanaka, Reiko; Fukushima, Takuya; Ansari, Aftab A; Tanaka, Yuetsu

    2016-01-01

    The environmental factors that lead to the reactivation of human T cell leukemia virus type-1 (HTLV-I) in latently infected T cells in vivo remain unknown. It has been previously shown that heat shock (HS) is a potent inducer of HTLV-I viral protein expression in long-term cultured cell lines. However, the precise HTLV-I protein(s) and mechanisms by which HS induces its effect remain ill-defined. We initiated these studies by first monitoring the levels of the trans-activator (Tax) protein induced by exposure of the HTLV-I infected cell line to HS. HS treatment at 43 °C for 30 min for 24 h led to marked increases in the level of Tax antigen expression in all HTLV-I-infected T cell lines tested including a number of HTLV-I-naturally infected T cell lines. HS also increased the expression of functional HTLV-I envelope gp46 antigen, as shown by increased syncytium formation activity. Interestingly, the enhancing effect of HS was partially inhibited by the addition of the heat shock protein 70 (HSP70)-inhibitor pifithlin-μ (PFT). In contrast, the HSP 70-inducer zerumbone (ZER) enhanced Tax expression in the absence of HS. These data suggest that HSP 70 is at least partially involved in HS-mediated stimulation of Tax expression. As expected, HS resulted in enhanced expression of the Tax-inducible host antigens, such as CD83 and OX40. Finally, we confirmed that HS enhanced the levels of Tax and gp46 antigen expression in primary human CD4⁺ T cells isolated from HTLV-I-infected humanized NOD/SCID/γc null (NOG) mice and HTLV-I carriers. In summary, the data presented herein indicate that HS is one of the environmental factors involved in the reactivation of HTLV-I in vivo via enhanced Tax expression, which may favor HTLV-I expansion in vivo. PMID:27409630

  17. The role of Ia molecules in the activation of T lymphocytes. III. Antigen-specific, Ia-restricted, interleukin 2-producing T cell hybridomas with detectable affinity for the restricting I-A molecule

    1983-01-01

    Antigen-specific I region-restricted, interleukin 2-producing T cell hybridomas were produced by fusing GAT-specific T cell blasts with BW5147. Two antigen-specific phenotypes were identified, one autoreactive and one nonautoreactive. All of the antigen-specific and autoreactive clones were H-2 restricted, mapping to the IA subregion by genetic analysis and monoclonal antibody inhibition. Both the antigen- specific and autoreactive stimulation are the property of a single cell and required no...

  18. Immunoassay of antigens

    A method is described of immunoassay of an antigen in a liquid sample wherein a complex is formed between antigen contained in the said sample and two or more antibody reagents, and the said complex is bound to a solid support by non-covalent bonding as defined herein: and the amount of complex becoming bound to the support is determined; the process employing at least one monoclonal antibody reagent. Labelling methods including radioactive, fluorimetric and enzyme labelling may be used to effect determination of the binding ofthe complex to the solid support. The solid support may take the form of particles, beads, wall-coatings on the reaction vessel or an insert of large surface area. The method is particularly applicable to the assay of TSH, CEA, HCG, alphafeto protein, immunoglobulins, viruses, allergens, bacteria, toxins, drugs and vitamins. Use of monoclonal reagents improves the specificity of the process, and also decreases non-specific binding

  19. Prevalence of hepatitis B surface antigen, hepatitis B e antigen and antibody, and antigen subtypes in atomic bomb survivors

    On the basis of previous studies showing an association between hepatitis B surface antigen (HBsAg) positivity and radiation exposure in atomic bomb (A-bomb) survivors, we investigated further the active state of hepatitis B virus (HBV) infection by incorporating tests of hepatitis B e antigen (HBeAg) and hepatitis B e antibody (anti-HBe) and HBsAg subtypes into our biennial health examinations. Among 6548 A-bomb survivors for whom HBsAg was assayed between July 1979 and July 1981, 129 persons were HBsAg positive. HBeAg and anti-HBe were measured in 104 of these persons and subtypes of HBsAg in 98 persons. Among those exposed to radiation (average liver dose 0.58 Sv), the odds ratio of HBsAg positivity tended to increase with radiation dose (P for trend = 0.024). The P values for association between the prevalence of HB e antigen and radiation dose were 0.094 and 0.17, respectively. The HB antigen subtype adr was predominant over other subtypes in both Hiroshima and Nagasaki, but the distribution of subtypes did not seem to differ in relation to radiation dose. These results suggested that A-bomb survivors remain in active state of HBV infection and that the mechanism(s) of seroconversion may be impaired. 29 refs., 6 tabs

  20. Antigen pulsed CpG-ODN activated dendritic cells induce host-protective immune response by regulating the T regulatory cell functioning in Leishmania donovani-infected mice: critical role of CXCL10

    Saikat eMajumder

    2014-06-01

    Full Text Available Visceral leishmaniasis (VL, caused by Leishmania donovani, is a systemic infection of reticulo-endothelial system. There is currently no protective vaccine against VL and chemotherapy is increasingly limited due to appearance of drug resistance to first line drugs such as antimonials and amphotericin B. In the present study, by using a murine model of leishmaniasis we evaluated the function played by soluble leishmanial antigen (SLA pulsed-CpG-ODN stimulated dendritic cells (SLA-CpG-DCs in restricting the intracellular parasitic growth. We establish that a single dose of SLA-CpG-DCs vaccination is sufficient in rendering complete protection against Leishmania donovani infection. In probing the possible mechanism, we observed that SLA-CpG-DCs vaccination results in the significant decrease in Foxp3+GITR+CTLA4+CD4+CD25+ Treg cell population in Leishmania-infected mice. Vaccination with these antigen stimulated dendritic cells results in the decrease in the secretion of TGF-β by these Treg cells by possible regulation of the SMAD signalling. Moreover, we demonstrated that a CXC chemokine, IFN-γ-inducible protein 10 (IP-10, has a direct role in the regulation of CD4+CD25+ Treg cells in SLA-CpG-DCs vaccinated parasitized mice as Treg cells isolated from IP-10 depleted vaccinated mice showed significantly increased TGF-β production and suppressive activity.

  1. Antigen receptor signaling: integration of protein tyrosine kinase functions.

    Tamir, I; Cambier, J C

    1998-09-17

    Antigen receptors on T and B cells function to transduce signals leading to a variety of biologic responses minimally including antigen receptor editing, apoptotic death, developmental progression, cell activation, proliferation and survival. The response to antigen depends upon antigen affinity and valence, involvement of coreceptors in signaling and differentiative stage of the responding cell. The requirement that these receptors integrate signals that drive an array of responses may explain their evolved structural complexity. Antigen receptors are composed of multiple subunits compartmentalized to provide antigen recognition and signal transduction function. In lieu of on-board enzymatic activity these receptors rely on associated Protein Tyrosine Kinases (PTKs) for their signaling function. By aggregating the receptors, and hence their appended PTKs, antigens induce PTK transphosphorylation, activating them to phosphorylate the receptor within conserved motifs termed Immunoreceptor Tyrosine-based Activation Motifs (ITAMs) found in transducer subunits. The tyrosyl phosphorylated ITAMs then interact with Src Homology 2 (SH2) domains within the PTKs leading to their further activation. As receptor phosphorylation is amplified, other effectors, such as Shc, dock by virtue of SH2 binding, and serve, in-turn, as substrates for these PTKs. This sequence of events not only provides a signal amplification mechanism by combining multiple consecutive steps with positive feedback, but also allows for signal diversification by differential recruitment of effectors that provide access to distinct parallel downstream signaling pathways. The subject of antigen receptor signaling has been recently reviewed in depth (DeFranco, 1997; Kurosaki, 1997). Here we discuss the biochemical basis of antigen receptor signal transduction, using the B cell receptor (BCR) as a paradigm, with specific emphasis on the involved PTKs. We review several specific mechanisms by which responses

  2. Human antigen-presenting cells respond differently to gut-derived probiotic bacteria but mediate similar strain-dependent NK and T cell activation.

    Fink, Lisbeth N; Zeuthen, Louise H; Ferlazzo, Guido; Frøkiaer, Hanne

    2007-12-01

    The intestinal microbiota is essential for homeostasis of the local and systemic immune system, and particularly strains of lactic acid bacteria and Escherichia coli have been shown to have balancing effects on inflammatory conditions such as allergy and inflammatory bowel disease. However, in vitro assessment of the immunomodulatory effects of distinct strains may depend strongly on the cell type used as a model. To select the most appropriate model for screening of beneficial bacteria in human cells, the response to strains of intestinal bacteria of three types of antigen-presenting cells (APC) was compared; blood myeloid dendritic cells (DC), monocyte-derived DC and monocytes, and the effector response of natural killer cells and naïve T cells was characterized. Maturation induced by gut-derived bacteria differed between APC, with blood DC and monocytes responding with the production of IL-6 and tumour necrosis factor-alpha to bacteria, which elicited mainly IL-10 in monocyte-derived DC. In contrast, comparable IFN-gamma production patterns were found in both natural killer cells and T cells induced by all bacteria-matured APC. An inhibitory effect of certain strains on this IFN-gamma production was also mediated by all types of APC. The most potent responses were induced by monocyte-derived DC, which thus constitute a sensitive screening model. PMID:17903206

  3. Enhancement of cytotoxic T lymphocyte activity by dendritic cells loaded with Tat-protein transduction domain-fused hepatitis B virus core antigen

    2008-01-01

    The protein transduction domain (PTD) of human immuno-deficiency virus-1-Tat protein has a unique potency to pen-etrate the cellular membranes. To synthesize the sequence of Tat-PTD and hepatitis B virus core antigen (HBcAg), we spliced these sequences and linked a fusion gene into the pMAL-c2x vector. The fusion proteins were purified by affin-ity chromatography and pulsed with bone marrow -derived den-dritic cells (DCs), and the transduction of recombinant pro-tein was detected by immunofluorescence antibody assay.Results showed that recombinant PTD-HBcAg could pen-etrate into DC cytoplasm while recombinant HBcAg was de-tected on the surface of cells. The percentage of DC surface molecules, such as CD80, CD86 and major histocompatibii-ity complex Ⅱ, and production of cytokine (IL-12pT0) induced by recombinant PTD-HBcAg were significantly higher than those induced by recombinant HBcAg or tumor necrosis fac-tor-α. DCs treated with PTD-HBcAg induced T cells to dif-ferentiate into specific cytotoxic T lymphocytes (CTLs) and enhanced the CTL killing response. In conclusion, the ex-pressed and purified PTD-HBcAg fusion protein could pen-etrate into cells through the plasma membrane, promote DC maturation, and enhance T cells response to generate HBcAg-specific CTLs efficiently.

  4. The expression and functional activity of membrane-bound human leukocyte antigen-G1 are influenced by the 3'-untranslated region

    Svendsen, Signe Goul; Hantash, Basil M; Zhao, Longmei; Faber, Carsten; Bzorek, Michael; Nissen, Mogens Holst; Hviid, Thomas Vauvert F

    2013-01-01

    Human Leukocyte Antigen (HLA)-G is an immunosuppressive molecule acting on both the innate and adaptive immune system. A 14 bp insertion/deletion polymorphism (rs66554220) in the 3'-untranslated region (3'UTR) of the HLA-G gene has been associated with a number of diseases, pregnancy complications......, and graft rejection after organ transplantation. We have investigated the effect of HLA-G polymorphism in the 3'UTR on the processing and stability of the membrane-bound HLA-G1 (mHLA-G1) isoform, as well as its functional significance. Different HLA-G1 cDNA sequences were transduced into the human K......562 cell line. Flow cytometry, immunohistochemistry, and ELISA were used to examine HLA-G1 protein expression. A quantitative RT-PCR assay was used to quantify transduced HLA-G1 DNA and mRNA transcript levels. Stability of mRNA and functional significance of HLA-G were investigated via Actinomycin D...

  5. Carcino-Embryonic Antigen

    Tumour marker analysis has increased our understanding of the presence of tumours in the body. Carcino-embryonic antigen, CEA, is one of the best studied tumour markers and has proved an ideal diagnostic adjuvant. It has helped in quantifying the amount of disease present in a patient and thence to make accurate prognosis on the various diagnosed ailments. At UCH, it is observed that there is an increase in cancer related ailments and therefore the need for early diagnosis is more compelling in our environment to mitigate future cost of managing advanced manifestation

  6. Binding of recombinant T cell receptor ligands (RTL) to antigen presenting cells prevents upregulation of CD11b and inhibits T cell activation and transfer of experimental autoimmune encephalomyelitis.

    Sinha, Sushmita; Miller, Lisa; Subramanian, Sandhya; McCarty, Owen J T; Proctor, Thomas; Meza-Romero, Roberto; Huan, Jianya; Burrows, Gregory G; Vandenbark, Arthur A; Offner, Halina

    2010-08-25

    Recombinant T cell ligands (RTLs) ameliorate experimental autoimmune encephalomyelitis (EAE) in an antigen-specific manner. We evaluated effects of RTL401 (I-A(s) alpha1beta1+PLP-139-151) on splenocytes from SJL/J mice with EAE to study RTL-T cell tolerance-inducing mechanisms. RTLs bound to B, macrophages and DCs, through RTL-MHC-alpha1beta1 moiety. RTL binding reduced CD11b expression on splenic macrophages/DC, and RTL401-conditioned macrophages/DC, not B cells, inhibited T cell activation. Reduced ability of RTL- incubated splenocytes to transfer EAE was likely mediated through macrophages/DC, since B cells were unnecessary for RTL treatment of EAE. These results demonstrate a novel pathway of T cell regulation by RTL-bound APCs. PMID:20546940

  7. Human leucocyte antigens in tympanosclerosis.

    Dursun, G; Acar, A; Turgay, M; Calgüner, M

    1997-02-01

    This study was designed to evaluate the association between certain HLA antigens and tympanosclerosis. The serum concentrations of HLA antigens were measured by a microlymphocytotoxicity technique in patients with tympanosclerosis and compared with a healthy control group. The serum levels of HLA-B35 and -DR3 were significantly higher in the patients with tympanosclerosis. This result suggests that certain types of HLA antigens may play an important role as an indicator or mediator in the pathogenesis of tympanosclerosis. PMID:9088683

  8. Antigenic variants of rabies virus

    Wiktor, TJ; Koprowski, H

    1980-01-01

    Antigenic variants of CVS-11 strain of rabies virus were selected after treatment of virus populations with monoclonal antibodies directed against the glycoprotein antigen of the virus. These variants resisted neutralization by the hybridoma antibody used for their selection. Two independently mutating antigenic sites could be distinguished when five variants were tested with nine hybridoma antibodies. The frequency of single epitope variants in a cloned rabies virus seed was approximately 1:...

  9. Structure-activity relationships of vanillic acid ester analogs in inhibitory effect of antigen-mediated degranulation in rat basophilic leukemia RBL-2H3 cells.

    Ishimata, Nao; Ito, Hideyuki; Tai, Akihiro

    2016-08-01

    Methyl vanillate (1) showed strong degranulation inhibitory activity among vanillin derivatives tested. In order to find structure-activity relationships for developing anti-allergic agents with simple structures and potent activity, we synthesized several vanillic acid (VA) ester derivatives with C1-C4 and C8 alkyl chains and evaluated their degranulation inhibitory activities. The most active compound of VA ester derivatives was derivative 5 with a C4 straight alkyl chain, and derivative 5 exhibited approximately three-fold greater inhibitory activity than that of 1. Moreover, we designed 8 types of analogs based on 5, and we found that the minimum structure for potent degranulation inhibitory activity requires direct connection of the butyl ester moiety on the benzene ring and at least one hydroxyl group on the benzene ring. Butyl meta or para hydroxyl benzoate (10 or 11) has a simpler structure than that of 5 and exhibited more potent degranulation inhibitory activity than that of 5. PMID:27324979

  10. 9 CFR 113.407 - Pullorum antigen.

    2010-01-01

    ... 9 Animals and Animal Products 1 2010-01-01 2010-01-01 false Pullorum antigen. 113.407 Section 113... and Reagents § 113.407 Pullorum antigen. Pullorum Antigen shall be produced from a culture of... standard for stained antigen K's and 50 ±10 times McFarland No. 1 standard for tube antigen....

  11. Neutrophil elastase enhances antigen presentation by upregulating human leukocyte antigen class I expression on tumor cells.

    Chawla, Akhil; Alatrash, Gheath; Philips, Anne V; Qiao, Na; Sukhumalchandra, Pariya; Kerros, Celine; Diaconu, Iulia; Gall, Victor; Neal, Samantha; Peters, Haley L; Clise-Dwyer, Karen; Molldrem, Jeffrey J; Mittendorf, Elizabeth A

    2016-06-01

    Neutrophil elastase (NE) is an innate immune cell-derived inflammatory mediator that we have shown increases the presentation of tumor-associated peptide antigens in breast cancer. In this study, we extend these observations to show that NE uptake has a broad effect on enhancing antigen presentation by breast cancer cells. We show that NE increases human leukocyte antigen (HLA) class I expression on the surface of breast cancer cells in a concentration and time-dependent manner. HLA class I upregulation requires internalization of enzymatically active NE. Western blots of NE-treated breast cancer cells confirm that the expression of total HLA class I as well as the antigen-processing machinery proteins TAP1, LMP2, and calnexin does not change following NE treatment. This suggests that NE does not increase the efficiency of antigen processing; rather, it mediates the upregulation of HLA class I by stabilizing and reducing membrane recycling of HLA class I molecules. Furthermore, the effects of NE extend beyond breast cancer since the uptake of NE by EBV-LCL increases the presentation of HLA class I-restricted viral peptides, as shown by their increased sensitivity to lysis by EBV-specific CD8+ T cells. Together, our results show that NE uptake increases the responsiveness of breast cancer cells to adaptive immunity by broad upregulation of membrane HLA class I and support the conclusion that the innate inflammatory mediator NE enhances tumor cell recognition and increases tumor sensitivity to the host adaptive immune response. PMID:27129972

  12. Molecular mimics of the tumour antigen MUC1.

    Tharappel C James

    Full Text Available A key requirement for the development of cancer immunotherapy is the identification of tumour-associated antigens that are differentially or exclusively expressed on the tumour and recognized by the host immune system. However, immune responses to such antigens are often muted or lacking due to the antigens being recognized as "self", and further complicated by the tumour environment and regulation of immune cells within. In an effort to circumvent the lack of immune responses to tumour antigens, we have devised a strategy to develop potential synthetic immunogens. The strategy, termed mirror image phage display, is based on the concept of molecular mimicry as demonstrated by the idiotype/anti-idiotype paradigm in the immune system. Here as 'proof of principle' we have selected molecular mimics of the well-characterised tumour associated antigen, the human mucin1 protein (MUC1 from two different peptide phage display libraries. The putative mimics were compared in structure and function to that of the native antigen. Our results demonstrate that several of the mimic peptides display T-cell stimulation activity in vitro when presented by matured dendritic cells. The mimic peptides and the native MUC1 antigenic epitopes can cross-stimulate T-cells. The data also indicate that sequence homology and/or chemical properties to the original epitope are not the sole determining factors for the observed immunostimulatory activity of the mimic peptides.

  13. Antigen antibody interactions

    DeLisi, Charles

    1976-01-01

    1. 1 Organization of the Immune System One of the most important survival mechanisms of vertebrates is their ability to recognize and respond to the onslaught of pathogenic microbes to which they are conti- ously exposed. The collection of host cells and molecules involved in this recognition­ 12 response function constitutes its immune system. In man, it comprises about 10 cells 20 (lymphocytes) and 10 molecules (immunoglobulins). Its ontogenic development is c- strained by the requirement that it be capable of responding to an almost limitless variety of molecular configurations on foreign substances, while simultaneously remaining inert to those on self components. It has thus evolved to discriminate, with exquisite precision, between molecular patterns. The foreign substances which induce a response, called antigens, are typically large molecules such as proteins and polysaccharides. The portions of these with which immunoglobulins interact are called epitopes or determinants. A typical protein epitope m...

  14. Trypanosoma cruzi: circulating antigens

    V. Bongertz

    1981-03-01

    Full Text Available Circulating antigens were detected in sera of mice experimentally infected with a high close of Trypanosoma cruzi by reaction with sera from chronically infected mice. The immunodiffusion reaction between homologous acute and chronic sera produced four precipitation lines. By reaction with chronic mouse serum, circulating antingens were detected in sera from heavily infected hamsters, dogs, rabbits and in sera from chagasic patients. A reaction was also found in urine from acutely infected mice and dogs. Trypanosoma cruzi exoantigen was detected in trypanosome culture medium and in the supernatant of infected cell cultures. Attempts to isolate the antigens are described.Antígenos circulantes foram detectados em soros de camundongos infectados experimentalmente com elevadas doses de Trypanosoma cruzi pela reação com soros obtidos de camundongos em fase crônica de infecção. A reação de imunodifusão entre soros homólogos agudo e crônico produziu quatro linhas de precipitação. Por reação com soro crônico de camundongo antígenos circulantes foram detectados em soros de crícetos, cães e coelhos infectados com doses elevadas de Trypanosoma cruzi e em soros de pacientes chagásicos. Uma reação foi também observada com urina de camundongos e cães infectados de forma aguda. Exoantígeno de Trypanosoma cruzi foi detectado em meio de cultura de tripanosomas e em sobrenadantes de culturas de células infectadas. Tentativas de isolamento dos antigenos são descritas.

  15. Cancer antigen 125 and prognosis

    Høgdall, Estrid Vilma Solyom

    2008-01-01

    PURPOSE OF REVIEW: This review addresses recently reported progress in cancer antigen 125 as a prognostic marker in patients with ovarian cancer. RECENT FINDINGS: Serum cancer antigen 125 levels measured preoperatively in both early and late stage ovarian cancer may be of prognostic value. Before...... cancer antigen 125 determination may be implemented into clinical practice, cut-off levels must be evaluated and internationally defined. Studies examining serum cancer antigen 125 levels after surgery but before, during, or after treatment confirmed that changes in serum levels are of prognostic value....... Furthermore, recent studies have shown that the level of expression of cancer antigen 125 in tissue may be an independent prognostic indicator in late stage ovarian cancer. SUMMARY: Prognostic markers may potentially help to individualize treatment within subgroups of patients. In a recent study the level of...

  16. Active treatment of murine tumors with a highly attenuated vaccinia virus expressing the tumor associated antigen 5T4 (TroVax) is CD4+ T cell dependent and antibody mediated.

    Harrop, Richard; Ryan, Matthew G; Myers, Kevin A; Redchenko, Irina; Kingsman, Susan M; Carroll, Miles W

    2006-09-01

    5T4 is a tumor associated antigen that is expressed on the surface of a wide spectrum of human adenocarcinomas. The highly attenuated virus, modified vaccinia Ankara, has been engineered to express human 5T4 (h5T4). In a pre-clinical murine model, the recombinant virus (TroVax) induces protection against challenge with CT26-h5T4 (a syngeneic tumor line expressing h5T4). Anti-tumor activity is long lived, with protection still evident 6 months after the final vaccination. In a therapeutic setting, injection of mice with TroVax results in a reduction in tumor burden of >90%. Depletion of CD8+ T cells has no effect upon therapy in the active treatment model, whereas depletion of CD4+ T cells completely abrogates anti-tumor activity. In a prophylactic setting, depletion of CD4+ and CD8+ T cells after the induction of a h5T4 immune response has no deleterious effect on protection following challenge with CT26-h5T4. In light of these studies, the role of antibodies in protection against tumor challenge was investigated. 5T4 specific polyclonal serum decreased tumor burden by approximately 70%. Thus, we conclude that CD4+ T cells are essential for the induction of a protective immune response and that antibodies are the likely effector moiety in this xenogeneic murine tumor model. PMID:16311730

  17. Monocytes and the 38kDa-antigen of mycobacterium tuberculosis modulate natural killer cell activity and their cytolysis directed against ovarian cancer cell lines

    Despite strong efforts to improve clinical outcome of ovarian cancer patients by conventional and targeted immuno-based therapies, the prognosis of advanced ovarian cancer is still poor. Natural killer (NK) cells mediate antibody-dependent cellular cytotoxicity (ADCC), release immunostimulatory cytokines and thus function as potent anti-tumour effector cells. However, tumour cells developed mechanisms to escape from an effective immune response. So highly immunogenic substances, like the 38 kDa-preparation of M. tuberculosis, PstS-1, are explored for their potential to enhance cancer-targeted immune responses. In this study we examined the modulation of different NK cell functions by accessory monocytes and PstS-1. We focussed on NK cell activation as well as natural and antibody-dependent cellular cytotoxicity directed against epidermal-growth-factor-receptor (EGFR)-positive ovarian cancer cell lines. Activation, cytokine release and cytotoxicity of NK cells stimulated by monocytes and PstS-1 were determined by FACS-analysis, ELISA, Bioplex assay and quantitative polymerase-chain reaction (qPCR). Transwell assays were used to discriminate cell-cell contact-dependent from contact-independent mechanisms. Five ovarian cancer cell lines (A2780, IGROV-1, OVCAR-3, OVCAR-4 and SKOV-3) with different EGFR-expression were used as target cells for natural and antibody-dependent cellular cytotoxicity assays. Cetuximab (anti-EGFR-antibody) was used for ADCC studies. Our data show that monocytes effectively enhance activation as well natural and antibody-dependent cytolytic activity of NK cells. PstS-1 directly stimulated monocytes and further activated monocyte-NK-co-cultures. However, PstS-1 did not directly influence purified NK cells and did also not affect natural and antibody-dependent cellular cytotoxicity directed against EGFR-positive ovarian cancer cells, even in presence of monocytes. Direct cell-cell contact between NK cells and monocytes was required for NK

  18. COLONOSCOPY AND CARCINOEMBRYONIC ANTIGEN VARIATIONS

    Rita G SOUSA

    2014-03-01

    Full Text Available Context Colonoscopy is essential for synchronous and metachronous cancer detection. Carcinoembryonic antigen is a colorectal cancer tumor marker, important as a follow-up tool in patients with previous colorectal cancer. False-positive carcinoembryonic antigen elevation results in multiples exams and in patient anxiety. In literature, there is reference to transient carcinoembryonic antigen increase with colonoscopy. Objective To evaluate the influence of bowel preparation and colonoscopy in carcinoembryonic antigen blood levels. Methods We prospectively studied subjects that underwent routine colonoscopy in our institution. Blood samples were collected (1 before bowel cleaning, (2 before colonoscopy and (3 immediately after colonoscopy. Blood carcinoembryonic antigen levels were determined by “Sandwich” immunoassay. The statistical methods used were the paired t-test and ANOVA. Results Thirty-seven patients (22M/15F were included; age range 28-84 (mean 56 years. Mean carcinoembryonic antigen values were 1.9, 2 and 1.8 for (1, (2 and (3, respectively. An increase in value (2 compared with (1 was observed in 20/37 patients (P = 0.018, mainly in younger patients and in patients requiring more endoluminal interventions. In 29/37 patients, the CEA value decreased from (2 to (3 (P = 1.3x10-7. Conclusions A trend for carcinoembryonic antigen increase after bowel cleaning was observed, especially in younger patients and in patients with more endoluminal interventions, but without clinical meaning.

  19. Antigen-presenting cells exposed to Lactobacillus acidophilus NCFM, Bifidobacterium bifidum BI-98, and BI-504 reduce regulatory T cell activity

    Schmidt, Esben Gjerløff Wedebye; Claesson, Mogens Helweg; Jensen, Simon Skjøde;

    2010-01-01

    enteroantigen-presenting cells (APC) and CD4(+)CD25(+) T-regulatory cells (Tregs) in splenocyte-T cell proliferation assays. METHODS:: Splenocytes exposed to enteroantigen +/- probiotics were used to stimulate cultured CD4(+)CD25(-) T cells to which titrated numbers of Tregs were added. Cytokine assays were...... performed by use of neutralizing antibodies and ELISA. RESULTS:: Exposure of APCs to enteroantigens and the series of probiotic strains mentioned above did not influence the stimulatory capacity of APCs on proliferative enteroantigen-specific T cells. However, exposure to B. bifidum BI-98, BI-504 and L....... acidophilus NCFM consistently reduced the suppressive activity of Tregs. The suppressive activity was analyzed using fractionated components of the probiotics, and showed that a component of the cell wall is responsible for the decreased Treg activity in the system. The probiotic-induced suppression of Treg...

  20. Classification of human leukocyte antigen (HLA) supertypes

    Wang, Mingjun; Claesson, Mogens H

    2014-01-01

    Identification of new antigenic peptides, derived from infectious agents or cancer cells, which bind to human leukocyte antigen (HLA) class I and II molecules, is of importance for the development of new effective vaccines capable of activating the cellular arm of the immune response. However, the...... barrier to the development of peptide-based vaccines with maximum population coverage is that the restricting HLA genes are extremely polymorphic resulting in a vast diversity of peptide-binding HLA specificities and a low population coverage for any given peptide-HLA specificity. One way to reduce this...... complexity is to group thousands of different HLA molecules into several so-called HLA supertypes: a classification that refers to a group of HLA alleles with largely overlapping peptide binding specificities. In this chapter, we focus on the state-of-the-art classification of HLA supertypes including HLA...

  1. Antibody-antigen-adjuvant conjugates enable co-delivery of antigen and adjuvant to dendritic cells in cis but only have partial targeting specificity.

    Martin Kreutz

    Full Text Available Antibody-antigen conjugates, which promote antigen-presentation by dendritic cells (DC by means of targeted delivery of antigen to particular DC subsets, represent a powerful vaccination approach. To ensure immunity rather than tolerance induction the co-administration of a suitable adjuvant is paramount. However, co-administration of unlinked adjuvant cannot ensure that all cells targeted by the antibody conjugates are appropriately activated. Furthermore, antigen-presenting cells (APC that do not present the desired antigen are equally strongly activated and could prime undesired responses against self-antigens. We, therefore, were interested in exploring targeted co-delivery of antigen and adjuvant in cis in form of antibody-antigen-adjuvant conjugates for the induction of anti-tumour immunity. In this study, we report on the assembly and characterization of conjugates consisting of DEC205-specific antibody, the model antigen ovalbumin (OVA and CpG oligodeoxynucleotides (ODN. We show that such conjugates are more potent at inducing cytotoxic T lymphocyte (CTL responses than control conjugates mixed with soluble CpG. However, our study also reveals that the nucleic acid moiety of such antibody-antigen-adjuvant conjugates alters their binding and uptake and allows delivery of the antigen and the adjuvant to cells partially independently of DEC205. Nevertheless, antibody-antigen-adjuvant conjugates are superior to antibody-free antigen-adjuvant conjugates in priming CTL responses and efficiently induce anti-tumour immunity in the murine B16 pseudo-metastasis model. A better understanding of the role of the antibody moiety is required to inform future conjugate vaccination strategies for efficient induction of anti-tumour responses.

  2. Non-major histocompatibility complex-restricted cytotoxic activity of blood mononuclear cells stimulated with secreted mycobacterial proteins and other mycobacterial antigens

    Ravn, P; Pedersen, B K

    1994-01-01

    Several observations indicate that non-major histocompatibility complex (MHC)-restricted cytotoxicity, mediated for example by natural killer cells and lymphokine-activated killer cells, may serve as an important antimicrobial defense mechanism. The purpose of the present study was to investigate...

  3. Minocycline modulates antigen-specific CTL activity through inactivation of mononuclear phagocytes in patients with HTLV-I associated neurologic disease

    Enose-Akahata Yoshimi

    2012-02-01

    Full Text Available Abstract Background The activation of mononuclear phagocytes (MPs, including monocytes, macrophages and dendritic cells, contributes to central nervous system inflammation in various neurological diseases. In HTLV-I-associated myelopathy/tropical spastic paraparesis (HAM/TSP, MPs are reservoirs of HTLV-I, and induce proinflammatory cytokines and excess T cell responses. The virus-infected or activated MPs may play a role in immuneregulation and disease progression in patients with HTLV-I-associated neurological diseases. Results Phenotypic analysis of CD14+ monocytes in HAM/TSP patients demonstrated high expression of CX3CR1 and HLA-DR in CD14lowCD16+ monocytes, compared to healthy normal donors (NDs and asymptomatic carriers (ACs, and the production of TNF-α and IL-1β in cultured CD14+ cells of HAM/TSP patients. CD14+ cells of HAM/TSP patients also showed acceleration of HTLV-I Tax expression in CD4+ T cells. Minocycline, an inhibitor of activated MPs, decreased TNF-α expression in CD14+ cells and IL-1β release in PBMCs of HAM/TSP patients. Minocycline significantly inhibited spontaneous lymphoproliferation and degranulation/IFN-γ expression in CD8+ T cells of HAM/TSP patients. Treatment of minocycline also inhibited IFN-γ expression in CD8+ T cells of HAM/TSP patients after Tax11-19 stimulation and downregulated MHC class I expression in CD14+ cells. Conclusion These results demonstrate that minocycline directly inhibits the activated MPs and that the downregulation of MP function can modulate CD8+ T cells function in HAM/TSP patients. It is suggested that activated MPs may be a therapeutic target for clinical intervention in HAM/TSP.

  4. Similarities and differences in signal transduction by interleukin 4 and interleukin 13: analysis of Janus kinase activation.

    Keegan, A D; Johnston, J A; Tortolani, P J; McReynolds, L J; Kinzer, C; O'Shea, J.J.; Paul, W. E.

    1995-01-01

    The cytokines interleukin (IL) 4 and IL-13 induce many of the same biological responses, including class switching to IgE and induction of major histocompatibility complex class II antigens and CD23 on human B cells. It has recently been shown that IL-4 induces the tyrosine phosphorylation of a 170-kDa protein, a substrate called 4PS, and of the Janus kinase (JAK) family members JAK1 and JAK3. Because IL-13 has many functional effects similar to those of IL-4, we compared the ability of IL-4 ...

  5. Liver disease and the e antigen in HBsAg carriers with chronic renal failure.

    Coughlin, G P; Van Deth, A G; Disney, A P; Hay, J; Wangel, A G

    1980-02-01

    This study was undertaken to assess the frequency of development and the stages of evolution of chronic liver disease in patients with renal failure who are chronic carriers of hepatitis B surface antigen. Cirrhosis or chronic active hepatitis developed in five of 21 patients and could not be predicted by the initial histological appearance or by HLA-A and B typing but was associated with the e antigen in four of the five patients. However, the antigen was not a consistent indicator of a poor prognosis, as the four other e antigen positive patients did not develop chronic liver disease during the period of the study. Transmission of hepatitis B to spouses occurred in four cases, was fatal in one instance, and was associated with e antigen in three of the four. Determination of e antigen status in renal unit patients who are carriers of hepatitis B surface antigen may be of value to the patient and his home environment. PMID:7380332

  6. Effect of mature dendritic cells primed with autologous tumor antigens, patients with epithelial ovarian cancer to stimulate the cytotoxic activity of mononuclear cells in vitro.

    Irina Obleuhova

    2013-01-01

    Along with conservative treatment of epithelial ovarian carcinoma, which has the highest frequency of occurrence of gynecological cancers, specific immunotherapy is a modern and advanced way of treating the disease. Special role in the immunotherapy vaccine therapy is based on dendritic cells (DC). Therefore, the purpose of this study was to assess the effectiveness of the modulation of cytotoxic activity in vitro (in a culture of mononuclear cells) using autologous dendritic cells and tumor ...

  7. DNA binding and antigene activity of a daunomycin-conjugated triplex-forming oligonucleotide targeting the P2 promoter of the human c-myc gene

    Giuseppina M. Carbone; McGuffie, Eileen; Napoli, Sara; Flanagan, Courtney E.; Dembech, Chiara; Negri, Umberto; Arcamone, Federico; Capobianco, Massimo L.; Catapano, Carlo V

    2004-01-01

    Triplex-forming oligonucleotides (TFO) that bind DNA in a sequence-specific manner might be used as selective repressors of gene expression and gene-targeted therapeutics. However, many factors, including instability of triple helical complexes in cells, limit the efficacy of this approach. In the present study, we tested whether covalent linkage of a TFO to daunomycin, which is a potent DNA-intercalating agent and anticancer drug, could increase stability of the triple helix and activity of ...

  8. Oncogenic cancer/testis antigens

    Gjerstorff, Morten F; Andersen, Mads H; Ditzel, Henrik J

    2015-01-01

    Recent developments have set the stage for immunotherapy as a supplement to conventional cancer treatment. Consequently, a significant effort is required to further improve efficacy and specificity, particularly the identification of optimal therapeutic targets for clinical testing. Cancer....../testis antigens are immunogenic, highly cancer-specific, and frequently expressed in various types of cancer, which make them promising candidate targets for cancer immunotherapy, including cancer vaccination and adoptive T-cell transfer with chimeric T-cell receptors. Our current understanding of tumor...... immunology and immune escape suggests that targeting oncogenic antigens may be beneficial, meaning that identification of cancer/testis antigens with oncogenic properties is of high priority. Recent work from our lab and others provide evidence that many cancer/testis antigens, in fact, have oncogenic...

  9. Control of T cell antigen reactivity via programmed TCR downregulation.

    Gallegos, Alena M; Xiong, Huizhong; Leiner, Ingrid M; Sušac, Bože; Glickman, Michael S; Pamer, Eric G; van Heijst, Jeroen W J

    2016-04-01

    The T cell antigen receptor (TCR) is unique in that its affinity for ligand is unknown before encounter and can vary by orders of magnitude. How the immune system regulates individual T cells that display very different reactivity to antigen remains unclear. Here we found that activated CD4(+) T cells, at the peak of clonal expansion, persistently downregulated their TCR expression in proportion to the strength of the initial antigen recognition. This programmed response increased the threshold for cytokine production and recall proliferation in a clone-specific manner and ultimately excluded clones with the highest antigen reactivity. Thus, programmed downregulation of TCR expression represents a negative feedback mechanism for constraining T cell effector function with a suitable time delay to thereby allow pathogen control while avoiding excess inflammatory damage. PMID:26901151

  10. Natural Selection Promotes Antigenic Evolvability

    Graves, C.J.; Ros, V.I.D.; Stevenson, B.; Sniegowski, P. D.; Brisson, D.

    2013-01-01

    The hypothesis that evolvability - the capacity to evolve by natural selection - is itself the object of natural selection is highly intriguing but remains controversial due in large part to a paucity of direct experimental evidence. The antigenic variation mechanisms of microbial pathogens provide an experimentally tractable system to test whether natural selection has favored mechanisms that increase evolvability. Many antigenic variation systems consist of paralogous unexpressed ‘cassettes...

  11. Novel vaccine strategies to T-independent antigens.

    Lesinski, G B; Westerink, M A

    2001-11-01

    T cell independent antigens do not require T cell help to induce an immune response, and are characterized by a lack of immunologic memory. These antigens can be divided into two classes, TI-1 or TI-2. TI-1 antigens, such as bacterial lipopolysaccharide, are potent B-cell mitogens, capable of non-specific, polyclonal activation of B cells. In contrast, TI-2 antigens can only activate mature B cells and consist of highly repetitive structures, such as capsular polysaccharides (CPS) from bacteria. Many vaccines currently in use consist of purified capsular polysaccharides from pathogenic bacteria such as Streptococcus pneumoniae and Neisseria meningitidis. These vaccines are efficacious in immune-competent adults, however, due to their TI-2 nature, are not effective in children <2 years of age. Converting polysaccharides into T cell dependent (TD) antigens, allows children, <2, to produce an effective immune response. This review focuses on various strategies used to convert the immune response to polysaccharide antigens from TI-2 to a TD response. Conjugate vaccines, anti-idiotypic antibodies, phage display library technology and DNA vaccines are discussed. PMID:11576678

  12. Substitution of Heavy Complementarity Determining Region 3 (CDR-H3) Residues Can Synergistically Enhance Functional Activity of Antibody and Its Binding Affinity to HER2 Antigen.

    Moon, Seung Kee; Park, So Ra; Park, Ami; Oh, Hyun Mi; Shin, Hyun Jung; Jeon, Eun Ju; Kim, Seiwhan; Park, Hyun June; Yeon, Young Joo; Yoo, Young Je

    2016-03-31

    To generate a biobetter that has improved therapeutic activity, we constructed scFv libraries via random mutagenesis of several residues of CDR-H3 and -L3 of hu4D5. The scFv clones were isolated from the phage display libraries by stringent panning, and their anti-proliferative activity against HER2-positive cancer cells was evaluated as a primary selection criterion. Consequently, we selected AH06 as a biobetter antibody that had a 7.2-fold increase in anti-proliferative activity (IC50: 0.81 nM) against the gastric cancer cell line NCI-N87 and a 7.4-fold increase in binding affinity (KD: 60 pM) to HER2 compared to hu4D5. The binding energy calculation and molecular modeling suggest that the substitution of residues of CDR-H3 to W98, F100c, A101 and L102 could stabilize binding of the antibody to HER2 and there could be direct hydrophobic interactions between the aromatic ring of W98 and the aliphatic group of I613 within HER2 domain IV as well as the heavy and light chain hydrophobic interactions by residues F100c, A101 and L102 of CDR-H3. Therefore, we speculate that two such interactions were exerted by the residues W98 and F100c. A101 and L102 may have a synergistic effect on the increase in the binding affinity to HER2. AH06 specifically binds to domain IV of HER2, and it decreased the phosphorylation level of HER2 and AKT. Above all, it highly increased the overall level of p27 compared to hu4D5 in the gastric cancer cell line NCI-N82, suggesting that AH06 could potentially be a more efficient therapeutic agent than hu4D5. PMID:26743905

  13. The prognostic value of oncogenic antigen 519 (OA-519) expression and proliferative activity detected by antibody MIB-1 in node-negative breast cancer

    Jensen, V; Ladekarl, M; Holm-Nielsen, P;

    1995-01-01

    invasion of skin or deep fascia (= T1N0M0 and T2N0M0). The median follow-up time was 104 months (range 5-143 months). Immunohistochemical analysis of OA-519 expression was performed on formalin-fixed, paraffin-embedded tissue. The proliferative activity was estimated using a Ki-67 equivalent monoclonal...... antibody (MIB-1), which is applicable on formalin-fixed, paraffin-embedded tissue after microwave pretreatment. OA-519 was expressed in about one-third of the tumours and the percentage of proliferating cells (the MIB-1 index) ranged between 1 and 72 per cent (median 17 per cent). Using multivariate Cox...

  14. Activation of human antigen-presenting cells by the mycobacterial cord factor and its glycolipid adjuvant analogue trehalose-6,6’-dibehenate

    Ostrop, Jenny

    2015-01-01

    The mycobacterial cord factor trehalose-6,6’-dimycolate (TDM) is an abundant cell wall glycolipid of Mycobacterium tuberculosis and other mycobacteria. It causes inflammation and adjuvanticity, but it is also a major virulence factor of M. tuberculosis. Its synthetic analogue trehalose-6,6’-dibehenate (TDB) has robust adjuvant activity and induces a Th1/Th17 T cell response in animal models. The TDB-containing liposomal adjuvant formulation Caf01 has entered phase I clinical studies in humans...

  15. Participation of L3T4 in T cell activation in the absence of class II major histocompatibility complex antigens. Inhibition by anti-L3T4 antibodies is a function both of epitope density and mode of presentation of anti-receptor antibody

    Owens, T; Fazekas de St Groth, B

    1987-01-01

    activation in the complete absence of class II MHC, immobilized antibody (either Sepharose-coupled or plastic-adsorbed) being more effective. The induction of IL 3 production by suboptimal doses of either Con A or plastic-adsorbed F23.1 was inhibited by the anti-L3T4 antibody GK1.5, as was the response to F...... of T cell/antigen interactions. By using antibodies against the T cell antigen receptor (TCR) to activate T cells, thereby circumventing the requirement for antigen presenting cells and MHC-associated antigen, we have been able to study the function of L3T4 in the absence of class II MHC. We have...... used two monoclonal antibodies, KJ16-133.18 and F23.1, that recognize a determinant encoded by the T cell receptor V beta 8 gene family. These antibodies were used to select two clones of T cells with surface phenotype Thy-1.2+, L3T4+, Lyt-2-, KJ16-133.18+, F23.1+, IA-, IE-. One of these clones (E9.D4...

  16. Anvendelse af prostataspecifikt antigen. En oversigt

    Brasso, K; Skaarup, P; Roosen, Jens Ulrik; Iversen, Peter

    1998-01-01

    Since it was first introduced, measurement of prostate specific antigen has gained increasing interest, and prostate specific antigen is regarded as being the best tumour marker available. The antigen lacks cancer specificity, limiting the usefulness in early diagnosis, The use of prostate specific...... antigen in early diagnosis, staging, and in monitoring patients with prostate cancer is reviewed....

  17. Activation of human monocytes by streptococcal rhamnose glucose polymers is mediated by CD14 antigen, and mannan binding protein inhibits TNF-alpha release.

    Soell, M; Lett, E; Holveck, F; Schöller, M; Wachsmann, D; Klein, J P

    1995-01-15

    The present work was initiated to define mechanisms that account for the binding on human monocytes of streptococcal cell wall polysaccharides formed by rhamnose glucose polymers (RGPs), and subsequent stimulatory activities. We show here that RGPs bind to and stimulate human monocytes to produce TNF-alpha in a dose-dependent manner. To detect cell surface RGPs binding proteins, intact monocytes were biotinylated before lysis with Nonidet P-40 and solubilized proteins were incubated with RGPs Affi-Prep beads. One major membrane protein of 55 kDa was specifically detected and identified as CD14 because it reacted with anti-CD14 mAbs. Furthermore, anti-CD14 mAbs were able to perform a dose-dependent inhibition of RGPs binding, and suppressed TNF-alpha release from RGPs-stimulated monocytes. Moreover, we demonstrated that RGPs also bind to CD11b; however, this binding is not implicated in synthesis of TNF-alpha. Interestingly, RGPs binding to monocytes was enhanced by human normal serum (HNS) whereas HNS inhibits the TNF-alpha-stimulating activity of RGPs. Western blotting analysis of HNS proteins purified on RGPs Affi-prep beads revealed three specific bands of 75, 55, and 32 kDa reactive with anti-C3 Abs, anti-CD14 mAbs (TUK4), and anti-human mannan binding protein (hMBP)-derived peptide IgG, respectively. These results suggest that C3, soluble CD14, and hMBP form complexes that are probably active in enhancing the binding of RGPs to monocytes. Additional studies have shown that hMBP that recognizes RGPs prevents, unlike the LPS binding protein, TNF-alpha release by inhibiting the binding of RGPs to CD14 Ag. By incubating cells with a constant amount of RGPs-hMBP complexes in the presence or absence of increasing concentrations of C1q, we also demonstrated that C1q receptor mediates the binding and probably the uptake of RGPs-hMBP complexes by human monocytes. PMID:7529289

  18. Proliferating cell nuclear antigen (PCNA) interacts with a meiosis-specific RecA homologues, Lim15/Dmc1, but does not stimulate its strand transfer activity

    PCNA is a multi-functional protein that is involved in various nuclear events. Here we show that PCNA participates in events occurring during early meiotic prophase. Analysis of protein-protein interactions using surface plasmon resonance indicates that Coprinus cinereus PCNA (CoPCNA) specifically interacts with a meiotic specific RecA-like factor, C. cinereus Lim15/Dmc1 (CoLim15) in vitro. The binding efficiency increases with addition of Mg2+ ions, while ATP inhibits the interaction. Co-immunoprecipitation experiments indicate that the CoLim15 protein interacts with the CoPCNA protein in vitro and in the cell extracts. Despite the interaction between these two factors, no enhancement of CoLim15-dependent strand transfer activity by CoPCNA was found in vitro. We propose that the interaction between Lim15/Dmc1 and PCNA mediates the recombination-associated DNA synthesis during meiosis

  19. Continuous activation of the CD122/STAT-5 signaling pathway during selection of antigen-specific regulatory T cells in the murine thymus.

    Jérémie D Goldstein

    Full Text Available Signaling events affecting thymic selection of un-manipulated polyclonal natural CD25(+foxp3(+ regulatory T cells (nTreg have not been established ex vivo. Here, we report a higher frequency of phosphorylated STAT-5 (pSTAT-5 in nTreg cells in the adult murine thymus and to a lesser extent in the periphery, compared to other CD4(+CD8(- subsets. In the neonatal thymus, the numbers of pSTAT-5(+ cells in CD25(+foxp3(- and nTreg cells increased in parallel, suggesting that pSTAT-5(+CD25(+foxp3(- cells might represent the precursors of foxp3(+ regulatory T cells. This "specific" pSTAT-5 expression detected in nTreg cells ex vivo was likely due to a very recent signal given by IL-2/IL-15 cytokines in vivo since (i it disappeared rapidly if cells were left unstimulated in vitro and (ii was also observed if total thymocytes were stimulated in vitro with saturating amounts of IL-2 and/or IL-15 but not IL-7. Interestingly, STAT-5 activation upon IL-2 stimulation correlated better with foxp3 and CD122 than with CD25 expression. Finally, we show that expression of an endogenous superantigen strongly affected the early Treg cell repertoire but not the proportion of pSTAT-5(+ cells within this repertoire. Our results reveal that continuous activation of the CD122/STAT-5 signaling pathway characterize regulatory lineage differentiation in the murine thymus.

  20. The Impacts of Helicobacter Pylori Antigen Positivity on Ankylosing Spondylitis

    Esra Erkol Ižnal

    2014-12-01

    Full Text Available Aim: We aimed to clarify the impacts of H. pylori infection on disease activity and clinical findings of AS. Material and Method: Forty-eight patients with AS were included in this study. The demographic data including age, sex, durations of the disease and medication of the patients were recorded. The laboratory analysis comprised Erythrocyte sedimentation rate (ESR, C-reactive protein (CRP and H. pylori antigen determination in gaita. The disease activity, functional disability and clinical status were assessed using the Bath Ankylosing Spondylitis Disease Activity Index (BASDAI, The Bath Ankylosing Spondylitis Functional index (BASFI and The Bath Ankylosing Spondylitis Metrology Index (BASMI respectively. We divided patients according to H. pylori antigen positivity in gaita as H. pylori positive and negative patients.Results: The mean age of patients was 41.9 11.8. CRP levels were slightly but not significantly higher in patients with positive H. pylori antigen compared to those in patients without H. pylori antigen in gaita (p=0.08. There was no significant difference in terms of ESR levels, BASDAI, BASFI and BASMI scores in patients with positive H. pylori antigen compared to those in patients with negative H. pylori antigen in gaita (p-values were >0.05 for all. In regression model BASDAI score was found to have no relationship with H. pylori antigen positivity, ESR and CRP levels (p-values were >0.05 for all. Discussion: H. pylori seemed to have probable impacts on the disease activity of AS. Studies with greater patient population and longer follow-up periods are warranted to enlighten this issue.

  1. Construction and Screening of Antigen Targeted Immune Yeast Surface Display Antibody Libraries

    Miller, Keith D.; Pefaur, Noah B.; Baird, Cheryl L.

    2008-07-01

    These protocols describe a yeast surface display-based process for the rapid selection of antibodies from immunized mice, eliminating the need for creating and screening hybridoma fusions. A yeast surface display library of single-chain antibody fragments (scFvs) is created from antigen-binding B cells from the splenocytes of immunized mice. The antigen targeted library is then screened for antigen specific scFv by magnetic activated cell sorting (MACS) and fluorescence activated cell sorting (FACS). Library construction and screening can be accomplished in as little as 2 weeks resulting in a panel of scFvs specific for the target antigen.

  2. Resistance of CD45RA- T cells to apoptosis and functional impairment, and activation of tumor-antigen specific T cells during radiation therapy of prostate cancer.

    Tabi, Zsuzsanna; Spary, Lisa K; Coleman, Sharon; Clayton, Aled; Mason, Malcolm D; Staffurth, John

    2010-07-15

    The effect of radiation therapy (RT) to the pelvis on circulating T cells was studied in prostate cancer (PCa) patients to provide a baseline for a more informed design of combination radioimmunotherapy. Peripheral blood samples taken from 12 PCa patients with locally advanced tumor before, during, and after hypofractionated RT were analyzed for T cell phenotype and function. There was significantly more loss of naive and early memory compared with more differentiated T cells during RT. The proportions of annexin-V(+) and Fas-expressing T cells were elevated in patients during RT and in PBMC irradiated in vitro ( 2-fold in the presence of an IkappaB-kinase inhibitor, indicating a protective effect via this pathway. T cell proliferation was impaired during RT with IL-2-dependent recovery post-RT. Recall T cell responses to common viral Ags, measured by IFN-gamma production, were little affected by RT. In vitro irradiation of healthy donor PBMCs resulted in a significantly increased frequency of responding T cells, due at least partly to the preferential elimination of CD45RA(+) T cells. Most importantly, antitumor CD4(+) and CD8(+) T cell responses were detectable after, but not before or during RT. The results indicate that generating tumor-specific T cell responses before RT and boosting their activity post-RT are ways likely to amplify the frequency and function of antitumor T cells, with implications for scheduling immunotherapy in PCa. PMID:20548027

  3. Double-antibody radioimmunoassay for factor VIII-related antigen

    A plasma protein required for the support of ristocetin-induced platelet aggregation was isolated from antihemophilic factor concentrate and radiolabeled with 125I. A double-antibody radioimmunoassay was developed, with use of specific rabbit anti-VIII related antigen serum and goat anti-rabbit globulin. The assay is sensitive, reproducible, and technically simple to perform. Values obtained in normal subjects ranged from 0.65 to 1.53 units, similar to our normal range for VIII coagulant activity (0.67 to 1.43 units). However, normal or increased values of VIII-related antigen were observed in VIII coagulant-deficient hemophiliacs. Also, concentrations of VIII-related antigen significantly exceeded coagulant concentrations in several patients with liver disease or disseminated intravascular coagulation, or both. Of a broad selection of congenital coagulation disorders examined, only patients with von Willebrand's disease had decreased VIII-related antigen concentrations, and these corresponded to the lowered concentration of ristocetin cofactor in the patients. In three transfused patients, VIII-related antigen values correlated with the concentration of the cofactor. Our results suggest that the radioimmunoassay of VIII-related antigen is a simple and valuable adjunct in the study of patients with clotting abnormalities

  4. The role of FcRn in antigen presentation

    Kristi eBaker

    2014-08-01

    Full Text Available Immunoglobulins are unique molecules capable of simultaneously recognizing a diverse array of antigens and themselves being recognized by a broad array of receptors. The abundance specifically of the IgG subclass and the variety of signaling receptors to which it binds render this an important immunomodulatory molecule. In addition to the classical Fcγ receptors (FcγR which bind IgG at the cell surface, the neonatal Fc receptor (FcRn is a lifelong resident of the endolysosomal system of most hematopoietic cells where it determines the intracellular fate of both IgG and IgG-containing immune complexes (IgG IC. Crosslinking of FcRn by multivalent IgG IC within antigen presenting cells such as dendritic cells (DC initiates specific mechanisms which result in trafficking of the antigen-bearing IgG IC into compartments from which the antigen can successfully be processed into peptide epitopes compatible with loading onto both MHC class I and II molecules. In turn, this enables the synchronous activation of both CD4+ and CD8+ T cell responses against the cognate antigen, thereby bridging the gap between the humoral and cellular branches of the adaptive immune response. Critically, FcRn-driven T cell priming is efficient at very low doses of antigen due to the exquisite sensitivity of the IgG-mediated antigen delivery system through which it operates. FcRn-mediated antigen presentation has important consequences in tissue compartments replete with IgG and serves not only to determine homeostatic immune activation at a variety of sites but also to induce inflammatory responses upon exposure to antigens perceived as foreign. Therapeutically targeting the pathway by which FcRn enables T cell activation in response to IgG IC is thus a highly attractive prospect not only for the treatment of diseases that are driven by immune complexes but also for manipulating local immune responses against defined antigens such as those present during infections and

  5. Cell Wall-Associated Protein Antigens of Streptococcus salivarius: Purification, Properties, and Function in Adherence

    Weerkamp, Anton H.; Jacobs, Ton

    1982-01-01

    Three cell wall-associated protein antigens (antigens b, c, and d) were isolated from mutanolysin-solubilized cell walls of Streptococcus salivarius HB and purified to apparent homogeneity by a combination of ion-exchange chromatography, gel filtration, and immunoadsorption chromatography. Antigens b and c were also isolated from culture supernatants. Antigen b consisted of more than 80% protein and had an apparent molecular weight as determined by sodium dodecyl sulfate-polyacrylamide gel electrophoresis of 320,000. Antigen c consisted of 57% protein, about 30% neutral sugar, and about 13% amino sugar, and its glycoprotein nature was confirmed by specific staining techniques. During sodium dodecyl sulfate-polyacrylamide gel electrophoresis antigen c resolved into two or more bands, depending on the source or the isolation procedure, in the molecular weight range from 220,000 to 280,000. Antigen d consisted of 95% protein and was observed in sodium dodecyl sulfate-polyacrylamide gel electrophoresis as two bands with molecular weights of 129,000 and 121,000. Under nondenaturing conditions all three antigens had molecular weights in the range from 1 × 106 to 3 × 106 as determined by gel filtration. The amino acid compositions of antigens b, c, and d were characterized by low amounts of basic amino acids and relatively high levels of nonpolar amino acids. Among oral streptococcal species antigens b and c were virtually restricted to strains of S. salivarius and most often to serotype I strains. Antigen b was recognized as the factor that mediates coaggregation of S. salivarius with Veillonella strains. The purified protein retained its biological activity. Antigen c could be linked to functions relating to adhesion of the streptococci to host tissues on the basis of its absence in mutant strains and blocking by specific antisera. The purified molecule had no detectable biological activity. Antigen d could not be linked to an established adhesion function. Images

  6. Enhancing the recognition of tumor associated antigens

    Restifo, Nicholas P; Irvine, Kari R.; Minev, Boris R.; Taggarse, Akash S.; McFariand, Barbra J.; Wang, Michael

    1994-01-01

    Activated CD8+ T cells (TCD8+) can directly recognize malignant cells because processed fragments of tumor associated antigens (TAA), 8-10 amino acids in length and complexed with MHC class I molecules, are displayed on tumor cell surfaces. Tumor cells have been genetically modified in a variety of ways in efforts to enhance the immune recognition of TAA. An alternative strategy is the expression of TAA in recombinant or synthetic form. This has been made possible by the recent cloning of TAA...

  7. [Farmer's lung antigens in Germany].

    Sennekamp, J; Joest, M; Sander, I; Engelhart, S; Raulf-Heimsoth, M

    2012-05-01

    Recent studies suggest that besides the long-known farmer's lung antigen sources Saccharopolyspora rectivirgula (Micropolyspora faeni), Thermoactinomyces vulgaris, and Aspergillus fumigatus, additionally the mold Absidia (Lichtheimia) corymbifera as well as the bacteria Erwinia herbicola (Pantoea agglomerans) and Streptomyces albus may cause farmer's lung in Germany. In this study the sera of 64 farmers with a suspicion of farmer's lung were examined for the following further antigens: Wallemia sebi, Cladosporium herbarum, Aspergillus versicolor, and Eurotium amstelodami. Our results indicate that these molds are not frequent causes of farmer's lung in Germany. PMID:22477566

  8. New Concepts in Tumor Antigens: Their Significance in Future Immunotherapies for Tumors

    Fan Yang; Xiao-Feng Yang

    2005-01-01

    The identification and molecular characterization of self-antigens expressed by human malignancies that are capable of elicitation of anti-tumor immune responses in patients have been an active field in tumor immunology.More than 2,000 tumor antigens have been identified, and most of these antigens are self-antigens. These significant progresses have led to the renaissance of tumor immunology and studies on anti-tumor immunotherapy.However, despite of the progress in the identification of self-tumor antigens, current antigen-specific immunotherapies for tumors are far less satisfied than expected, which reflects the urgent need to improve our understanding on self-tumor antigens. In order to develop more effective antigen specific anti-tumor immunotherapies and to monitor the responses to these immunotherapies in patients with tumors, many important fundamental questions need to be addressed. We propose for the first time that the studies in addressing the characteristics of self-tumor antigens and autoantigens are grouped as a new subject termed "antigenology". In this brief review, we would outline the progress in the identification of tumor antigens in solid tumors and hematologic malignancies, and overview the new concepts and principles of antigenology and their significance for future immunotherapies to these malignancies. Cellular & Molecular Immunology.

  9. Surface membrane antigen expression changes induced in vitro by exogenous growth factors in chronic lymphocytic leukemia cells.

    Vilpo, J; Hulkkonen, J; Hurme, M; Vilpo, L

    2002-09-01

    The factors determining the growth and survival of cells in B chronic lymphocytic leukemia (CLL) have remained poorly understood. We investigated the effects of optimal mitogen combinations (OMCs) on the expression of 26 surface membrane antigens among 33 CLL patients. The seven OMCs used were selected after pre-testing 14 combinations of (1) S. aureus Cowan I (SAC), (2) interleukin-2 (IL-2), (3) tumor necrosis factor alpha (TNF-alpha) and (4) 12-O-tetradecanoylphorbol 13-acetate (TPA; also known as phorbol 12-myristate 13-acetate or PMA). In flow cytometry we revealed that OMCs induced statistically highly significant upregulation of the expression of CD5, CD11c, CD19, CD22, CD23, CD25, CD38, CD40, CD45, CD45RO, CD95, CD126, CD130 and FMC7, and downregulation of CD20 and CD124 expression. Interestingly, the expression of CD27, CD45RA, CD79b, CD80, CD122 and that of the immunoglobulin gene superfamily members CD21, Ig-kappa, Ig-lambda, Ig-delta and Ig-micro were not significantly affected under similar conditions. The expression of several antigens was co-regulated, suggesting common regulatory pathways. These antigens include CD11c/CD5, CD11c/CD22, CD11c/CD126, CD11c/FMC7 as well as CD27/CD45, CD27/CD45RA and CD27/CD79b. Upregulation of surface antigen expression, induced by OMCs, should be applicable in antibody therapy in vitro and in vivo, and in negative stem cell selection for autotransplantation. Furthermore, the current strategy to enhance cell surface antigen expression may be a versatile tool to raise humoral and cell-mediated host defense against CLL cells. Upregulation of proteins mediating positive growth signals (eg CD25, CD40) and negative signals or apoptosis (eg CD95) may be used to sensitize cells to chemotherapy and programmed cell death. PMID:12200683

  10. ONCOLYTIC VIRUS-MEDIATED REVERSAL OF IMPAIRED TUMOR ANTIGEN PRESENTATION

    Shashi Ashok Gujar

    2014-04-01

    Full Text Available Anti-tumor immunity can eliminate existing cancer cells and also maintain a constant surveillance against possible relapse. Such an antigen-specific adaptive response begins when tumor-specific T cells become activated. T cell activation requires two signals on antigen presenting cells (APCs: antigen presentation through MHC molecules and co-stimulation. In the absence of one or both of these signals, T cells remain inactivated or can even become tolerized. Cancer cells and their associated microenvironment strategically hinder the processing and presentation of tumor antigens and consequently prevent the development of anti-tumor immunity. Many studies, however, demonstrate that interventions that overturn tumor-associated immune evasion mechanisms can establish anti-tumor immune responses of therapeutic potential. One such intervention is oncolytic virus (OV-based anti-cancer therapy. Here we discuss how OV-induced immunological events override tumor-associated antigen presentation impairment and promote appropriate T cell:APC interaction. Detailed understanding of this phenomenon is pivotal for devising the strategies that will enhance the efficacy of OV-based anti-cancer therapy by complementing its inherent oncolytic

  11. Construction and Screening of Antigen Targeted Immune Yeast Surface Display Antibody Libraries

    Miller, Keith D.; Pefaur, Noah B.; Baird, Cheryl L.

    2009-08-02

    These protocols describe a yeast surface display-based process for the rapid selection of antibodies from immunized mice, eliminating the need for creating and screening hybridoma fusions. A yeast surface display library of single-chain antibody fragments (scFvs) is created from antigen-binding B cells from the splenocytes of immunized mice. The antigen targeted library is then screened for antigen specific scFv by magneticactivated cell sorting (MACS) and fluorescence-activated cell sorting (FACS). Library construction and screening can be accomplished in as little as 2 weeks, resulting in a panel of scFvs specific for the target antigen.

  12. Low dose antigen promotes induction of FOXP3 in human CD4+ T cells

    Long, S. Alice; Rieck, Mary; Tatum, Megan; Bollyky, Paul L.; Wu, Rebecca P.; Muller, Isabelle; Ho, Jhon-Chun; Shilling, Heather G.; Buckner, Jane H.

    2011-01-01

    Low antigen dose promotes induction and persistence of Treg in mice, yet few studies have addressed the role of antigen dose in the induction of adaptive CD4+FOXP3+ Treg in humans. To this end, we examined the level of FOXP3 expression in human CD4+CD25− T cells upon activation with autologous antigen presenting cells and varying doses of peptide. Antigen specific T cells expressing FOXP3 were identified by flow cytometry using MHC Class II tetramer (Tmr). We found an inverse relationship bet...

  13. Germinal center B cells recognize antigen through a specialized immune synapse architecture.

    Nowosad, Carla R; Spillane, Katelyn M; Tolar, Pavel

    2016-07-01

    B cell activation is regulated by B cell antigen receptor (BCR) signaling and antigen internalization in immune synapses. Using large-scale imaging across B cell subsets, we found that, in contrast with naive and memory B cells, which gathered antigen toward the synapse center before internalization, germinal center (GC) B cells extracted antigen by a distinct pathway using small peripheral clusters. Both naive and GC B cell synapses required proximal BCR signaling, but GC cells signaled less through the protein kinase C-β-NF-κB pathway and produced stronger tugging forces on the BCR, thereby more stringently regulating antigen binding. Consequently, GC B cells extracted antigen with better affinity discrimination than naive B cells, suggesting that specialized biomechanical patterns in B cell synapses regulate T cell-dependent selection of high-affinity B cells in GCs. PMID:27183103

  14. Effects of fucosylated milk of goat and mouse on Helicobacter pylori binding to Lewis b antigen

    Hong-Tao Xu; Ning Li; Lennart Hammarstr(o)m; Thomas Borén; Rolf Sj(o)str(o)m; Yao-Feng Zhao; Zheng-Xing Lian; Bao-Liang Fan; Zhi-Hui Zhao; Shu-Yang Yu; Yun-Ping Dai; Li-Li Wang; Hui-Ling Niu

    2004-01-01

    AIM: To evaluate the effects of animal milk containing fucosylated antigens on Helicobacter pylori (Hpylori) binding to Lewis b antigen.METHODS: A mammary gland expression vector containing human α1-3/4-fucosyltransferase cDNA sequences was constructed. Transient expression of human α1-3/4-fucosyltransferase cDNA in goat mammary cell and establishment of transgenic mice were performed. The adhesion inhibitory properties of milk samples were analyzed by using H pylori RESULTS: Goat milk samples were found to inhibit bacterial binding to Lewis b antigen. The highest inhibition was observed 42 h after injection of the plasmid. The binding activity of Hpylori to Lewis b antigen reduced mostly, by 83%, however milk samples from transgenic mice did not inhibit H pylori binding to Lewis b antigen.CONCLUSION: The use of "humanized" animal milk produced by the transgenic introduction of fucosylated antigen can perhaps provide an alternative therapy and preventive measure for H pylori infection.

  15. Major histocompatibility complex (MHC) antigens

    Hála, K.; Plachý, Jiří; Kaufman, J.

    New York : Academic Press, 1998 - (Pastoret, P.; Griebel, P.; Bazin, H.; Govaerts, A.), s. 92-95 ISBN 0-12-546401-0 R&D Projects: GA ČR GA523/96/0670 Keywords : chicken MHC * histocompatibility antigens * disease resistance Subject RIV: EB - Genetics ; Molecular Biology

  16. Retrovirus antigens in brains of mice with scrapie- and murine leukemia virus-induced spongiform encephalopathy.

    Hoffman, P M; Pitts, O M; Rohwer, R. G.; Gajdusek, D C; Ruscetti, S K

    1982-01-01

    Wild mouse ecotropic virus-induced spongiform encephalomyelopathy pathologically similar to scrapie was associated with the expression of retrovirus antigens in mouse brains. However, scrapie-infected mice with spongiform encephalopathy showed no increased expression of retrovirus antigens in brain. Thus, the pathogenesis of the scrapie spongiform lesion does not appear to involve activation of endogenous retrovirus.

  17. Lamivudinbehandling af en hepatitis Bs- antigen-positiv patient med reaktiv artritis

    Borup, Christian; Siboni, Anders

    2008-01-01

    A 46-year-old man who was HBs antigen positive since childhood had painful talocrural arthritis that was considered re-active to HBs antigen. Lamivudine treatment was started and HBV-DNA disappeared from the blood, and the joint swellings disappeared. HBe antibody disappeared after eight months. ...

  18. Peripheral blood lymphocytes from low-grade squamous intraepithelial lesions patients recognize vaccine antigens in the presence of activated dendritic cells, and produced high levels of CD8 + IFNγ + T cells and low levels of IL-2 when induced to proliferate

    Hernández-Montes Jorge

    2012-05-01

    Full Text Available Abstract Background Most infections with human papillomavirus (HPV are resolved without clinical intervention, but a minority evolves into chronic lesions of distinct grades, including cervical-uterine cancer. It is known that in most cases the immune system mediates elimination of HPV infection. However, the mechanism of immune evasion leading to HPV persistence and development of early cervical lesions is not fully understood. The aim of the present work was to evaluate the potential of peripheral blood leukocytes (PBL from low-grade squamous intraepithelial lesions (LSIL patients to be activated ex-vivo by vaccine antigens, the participation of cytotoxic lymphocytes and regulatory T cells, and to determine the secretion of Th1 and Th2 cytokines mediated by stimulation of T cell receptors. Results We found that PBL from LSIL patients showed a significantly lower proliferation rate to vaccine antigens as compared to that of healthy donors, even though there was not a difference in the presence of antibodies to those antigens in sera from both groups. We did not find differences in either the frequency of CD4 + CD25 + FoxP3+ in PBL, or the levels of IL-4, IL-5 and IL-10 in plasma or conditioned media from PBL incubated with TcR agonists in vitro, between the two groups. However, we detected a lower production of IL-2 and a higher proportion of CD8 + IFNγ + cells in PBL from LSIL patients as compared with PBL from normal donors. We also observed that PBL from patients infected by HPV-16 and −18 were not able to proliferate in the presence of soluble HPV antigens added to the culture; however, a high level of proliferation was attained when these antigens were presented by activated dendritic cells. Conclusions Our results suggest that the immunodeficiency reported in LSIL patients could be due to the inability of specific cytotoxic T lymphocytes that for some unknown reason are present but unable to mount a response when

  19. Genome Scale Identification of Treponema pallidum Antigens

    McKevitt, Matthew; Brinkman, Mary Beth; McLoughlin, Melanie; Perez, Carla; Howell, Jerrilyn K.; Weinstock, George M.; Norris, Steven J; Palzkill, Timothy

    2005-01-01

    Antibody responses for 882 of the 1,039 proteins in the proteome of Treponema pallidum were examined. Sera collected from infected rabbits were used to systematically identify 106 antigenic proteins, including 22 previously identified antigens and 84 novel antigens. Additionally, sera collected from rabbits throughout the course of infection demonstrated a progression in the breadth and intensity of humoral immunoreactivity against a representative panel of T. pallidum antigens.

  20. IgE production after antigen-specific and cognate activation of HLA-DPw4-restricted T-cell clones, by 78% of randomly selected B-cell donors

    Baselmans, PJ; Pollabauer, EM; van Reijsen, FC; Heystek, HC; Hren, A; Stumptner, P; Tilanus, MGJ; Vooijs, WC; Mudde, GC

    2000-01-01

    The frequency of expression of the MHC class II antigen, HLA-DPw4, in the caucasoid population is approximately 78%, and is unmatched by phenotypic frequencies of other HLA class II molecules. Here we describe three human Der-P1-specific T-cell clones (TCC), restricted by the HLA-DPw4-variant HLA-DP

  1. Detection of O antigens in Escherichia coli

    Lipopolysaccharide on the surface of Escherichia coli constitute the O antigens, which are important virulence factors that are targets of both the innate and adaptive immune system and play a major role in host-pathogen interactions. O antigens that are responsible for antigenic specificity of the ...

  2. Plague virulence antigens from Yersinia enterocolitica.

    Carter, P B; Zahorchak, R J; Brubaker, R R

    1980-01-01

    The virulence of Yersinia enterocolitica, biotype 2, serotype O:8, in mice is related to its ability to produce plague V and W antigens. V and W antigens in Y. enterocolitica are shown to be immunologically identical to the previously described V and W antigens of Yersinia pestis and Yersinia pseudotuberculosis.

  3. Molecular characterization of common treponemal antigens.

    Hanff, P A; Miller, J N; Lovett, M A

    1983-01-01

    A molecular characterization of cross-reactive antigens of Treponema pallidum Nichols and Treponema phagedenis biotype Reiter that are reactive with normal and syphilitic human sera is described. At least 8 common polypeptides, 14 T. pallidum-specific antigens, and 2 T. phagedenis biotype Reiter-specific antigens were identified.

  4. Antigenic determinants and functional domains in core antigen and e antigen from hepatitis B virus

    The precore/core gene of hepatitis B virus directs the synthesis of two polypeptides, the 21-kilodalton subunit (p21c) forming the viral nucleocapsid (serologically defined as core antigen [HBcAg]) and a secreted processed protein (p17e, serologically defined as HBe antigen [HBeAg]). Although most of their primary amino acid sequences are identical, HBcAg and HBeAg display different antigenic properties that are widely used in hepatitis B virus diagnosis. To locate and to characterize the corresponding determinants, segments of the core gene were expressed in Escherichia coli and probed with a panel of polyclonal or monoclonal antibodies in radioimmunoassays or enzyme-linked immunosorbent assays, Western blots, and competition assays. Three distinct major determinants were characterized. It is postulated that HBcAg and HBeAg share common basic three-dimensional structure exposing the common linear determinant HBe1 but that they differ in the presentation of two conformational determinants that are either introduced (HBc) or masked (HBe2) in the assembled core. The simultaneous presentation of HBe1 and HBc, two distinctly different antigenic determinants with overlapping amino acid sequences, is interpreted to indicate the presence of slightly differently folded, stable conformational states of p21c in the hepatitis virus nucleocapsid

  5. State of the Art in Tumor Antigen and Biomarker Discovery

    Our knowledge of tumor immunology has resulted in multiple approaches for the treatment of cancer. However, a gap between research of new tumors markers and development of immunotherapy has been established and very few markers exist that can be used for treatment. The challenge is now to discover new targets for active and passive immunotherapy. This review aims at describing recent advances in biomarkers and tumor antigen discovery in terms of antigen nature and localization, and is highlighting the most recent approaches used for their discovery including “omics” technology

  6. State of the Art in Tumor Antigen and Biomarker Discovery

    Patrick Chames

    2011-06-01

    Full Text Available Our knowledge of tumor immunology has resulted in multiple approaches for the treatment of cancer. However, a gap between research of new tumors markers and development of immunotherapy has been established and very few markers exist that can be used for treatment. The challenge is now to discover new targets for active and passive immunotherapy. This review aims at describing recent advances in biomarkers and tumor antigen discovery in terms of antigen nature and localization, and is highlighting the most recent approaches used for their discovery including “omics” technology.

  7. State of the Art in Tumor Antigen and Biomarker Discovery

    Even-Desrumeaux, Klervi; Baty, Daniel; Chames, Patrick, E-mail: patrick.chames@inserm.fr [INSERM U624, 163 avenue de Luminy, 13288 Marseille Cedex 09 (France)

    2011-06-09

    Our knowledge of tumor immunology has resulted in multiple approaches for the treatment of cancer. However, a gap between research of new tumors markers and development of immunotherapy has been established and very few markers exist that can be used for treatment. The challenge is now to discover new targets for active and passive immunotherapy. This review aims at describing recent advances in biomarkers and tumor antigen discovery in terms of antigen nature and localization, and is highlighting the most recent approaches used for their discovery including “omics” technology.

  8. Immunoprotective activity of a Salmonid Alphavirus Vaccine: comparison of the immune responses induced by inactivated whole virus antigen formulations based on CpG class B oligonucleotides and poly I:C alone or combined with an oil adjuvant.

    Thim, Hanna L; Iliev, Dimitar B; Christie, Karen E; Villoing, Stéphane; McLoughlin, Marian F; Strandskog, Guro; Jørgensen, Jorunn B

    2012-07-01

    CpG oligonucleotides and polyinosinic:polycytidylic acid (poly I:C) are toll-like receptor (TLR) agonists that mimic the immunostimulatory properties of bacterial DNA and double-stranded viral RNA respectively, and which have exhibited potential to serve as vaccine adjuvants in previous experiments. Here, a combination of CpGs and poly I:C together with water- or oil-formulated Salmonid Alphavirus (SAV) antigen preparations has been used for a vaccine in Atlantic salmon and tested for protection in SAV challenge trial. The results demonstrate that vaccination with a high dose of the SAV antigen induced protection against challenge with SAV which correlated with production of neutralizing antibodies (NAbs). As the high antigen dose alone induced full protection, no beneficial effect from the addition of CpG and poly I:C could be observed. Nevertheless, these TLR ligands significantly enhanced the levels of NAbs in serum of vaccinated fish. Interestingly, gene expression analysis demonstrated that while addition of oil suppressed the CpG/poly I:C-induced expression of IFN-γ, the upregulation of IFNa1 was substantially enhanced. A low dose of the SAV antigen combined with oil did not induce any detectable levels of NAbs either with or without TLR ligands present, however the addition of CpG and poly I:C to the low SAV antigen dose formulation significantly enhanced the protection against SAV suggesting that CpG/poly I:C may have enhanced a cytotoxic response - a process which is dependent on the up-regulation of type I IFN. These results highlight the immunostimulatory properties of the tested TLR ligands and will serve as a ground for further, more detailed studies aimed to investigate their capacity to serve as adjuvants in vaccine formulations for Atlantic salmon. PMID:22634299

  9. Rationally designed inhibitor targeting antigen-trimming aminopeptidases enhances antigen presentation and cytotoxic T-cell responses.

    Zervoudi, Efthalia; Saridakis, Emmanuel; Birtley, James R; Seregin, Sergey S; Reeves, Emma; Kokkala, Paraskevi; Aldhamen, Yasser A; Amalfitano, Andrea; Mavridis, Irene M; James, Edward; Georgiadis, Dimitris; Stratikos, Efstratios

    2013-12-01

    Intracellular aminopeptidases endoplasmic reticulum aminopeptidases 1 and 2 (ERAP1 and ERAP2), and as well as insulin-regulated aminopeptidase (IRAP) process antigenic epitope precursors for loading onto MHC class I molecules and regulate the adaptive immune response. Their activity greatly affects the antigenic peptide repertoire presented to cytotoxic T lymphocytes and as a result can regulate cytotoxic cellular responses contributing to autoimmunity or immune evasion by viruses and cancer cells. Therefore, pharmacological regulation of their activity is a promising avenue for modulating the adaptive immune response with possible applications in controlling autoimmunity, in boosting immune responses to pathogens, and in cancer immunotherapy. In this study we exploited recent structural and biochemical analysis of ERAP1 and ERAP2 to design and develop phosphinic pseudopeptide transition state analogs that can inhibit this family of enzymes with nM affinity. X-ray crystallographic analysis of one such inhibitor in complex with ERAP2 validated our design, revealing a canonical mode of binding in the active site of the enzyme, and highlighted the importance of the S2' pocket for achieving inhibitor potency. Antigen processing and presentation assays in HeLa and murine colon carcinoma (CT26) cells showed that these inhibitors induce increased cell-surface antigen presentation of transfected and endogenous antigens and enhance cytotoxic T-cell responses, indicating that these enzymes primarily destroy epitopes in those systems. This class of inhibitors constitutes a promising tool for controlling the cellular adaptive immune response in humans by modulating the antigen processing and presentation pathway. PMID:24248368

  10. Artificial Loading of ASC Specks with Cytosolic Antigens.

    Ali Can Sahillioğlu

    Full Text Available Inflammasome complexes form upon interaction of Nod Like Receptor (NLR proteins with pathogen associated molecular patterns (PAPMS inside the cytosol. Stimulation of a subset of inflammasome receptors including NLRP3, NLRC4 and AIM2 triggers formation of the micrometer-sized spherical supramolecular complex called the ASC speck. The ASC speck is thought to be the platform of inflammasome activity, but the reason why a supramolecular complex is preferred against oligomeric platforms remains elusive. We observed that a set of cytosolic proteins, including the model antigen ovalbumin, tend to co-aggregate on the ASC speck. We suggest that co-aggregation of antigenic proteins on the ASC speck during intracellular infection might be instrumental in antigen presentation.

  11. Delayed type hypersensitivity to allogeneic mouse epidermal cell antigens, 2

    A low dose of ultraviolet B radiation impairs the effectiveness of epidermal cell antigens. We studied the effect of ultraviolet B radiation on the delayed type hypersensitivity induced by allogeneic epidermal cell antigen. The delayed type hypersensitivity response was assayed by footpad swelling in mice. When epidermal cells were exposed to ultraviolet B radiation (660 J/m2), their ability to induce T cells of delayed type hypersensitivity activation was markedly inhibited in any combination of recipient mice and allogeneic epidermal cells. The effect of ultraviolet B radiation on epidermal cells was observed before immunization and challenge. Ultraviolet B treated epidermal cells did not induce suppressor T cells in mice. These results indicate that ultraviolet B radiation destroys the antigenicity of epidermal cells. (author)

  12. Development of the Artificial Antigens for the Organophosphorus Insecticide chlorpyrifos

    ZHU Guo-nian; WU Gang; WU Hui-ming

    2004-01-01

    This study reported that the hapten of the organophosphorus insecticide chlorpyrifos,O,Odiethyl-O-[3,5-dichloro-6-(2-carboxyethyl)thio-2-pyridyl]phosphorothioate(named AR) was synthesized by using technical grade chlorpyrifos reacted with 3-marcapropanoic acid in hot alkaline solution.The hapten was conjugated to bovine serum albumin (BSA) with the modified active ester method to form artificial immune antigen.The ratio of AR:BSA was 39:1.The artificial coating antigen for chlorpyrifos was synthesized by conjugating AR to ovalbumin (OVA) with the mixed-anhydride method,and the ratio was 13:1.The anti-chlorpyrifos polyclonal antibodies were obtained by using the artificial immune antigen (AR-BSA) to immune in the rabbits.

  13. CD28 and T cell antigen receptor signal transduction coordinately regulate interleukin 2 gene expression in response to superantigen stimulation

    1992-01-01

    Activation of an immune response requires intercellular contact between T lymphocytes and antigen-presenting cells (APC). Interaction of the T cell antigen receptor (TCR) with antigen in the context of major histocompatibility molecules mediates signal transduction, but T cell activation appears to require the induction of a second costimulatory signal transduction pathway. Recent studies suggest that interaction of CD28 with B7 on APC might deliver such a costimulatory signal. To investigate...

  14. Production of Functionally Active and Immunogenic Non-Glycosylated Protective Antigen from Bacillus anthracis in Nicotiana benthamiana by Co-Expression with Peptide-N-Glycosidase F (PNGase F) of Flavobacterium meningosepticum.

    Mamedov, Tarlan; Chichester, Jessica A; Jones, R Mark; Ghosh, Ananya; Coffin, Megan V; Herschbach, Kristina; Prokhnevsky, Alexey I; Streatfield, Stephen J; Yusibov, Vidadi

    2016-01-01

    Bacillus anthracis has long been considered a potential biological warfare agent, and therefore, there is a need for a safe, low-cost and highly efficient anthrax vaccine with demonstrated long-term stability for mass vaccination in case of an emergency. Many efforts have been made towards developing an anthrax vaccine based on recombinant protective antigen (rPA) of B. anthracis, a key component of the anthrax toxin, produced using different expression systems. Plants represent a promising recombinant protein production platform due to their relatively low cost, rapid scalability and favorable safety profile. Previous studies have shown that full-length rPA produced in Nicotiana benthamiana (pp-PA83) is immunogenic and can provide full protection against lethal spore challenge; however, further improvement in the potency and stability of the vaccine candidate is necessary. PA of B. anthracis is not a glycoprotein in its native host; however, this protein contains potential N-linked glycosylation sites, which can be aberrantly glycosylated during expression in eukaryotic systems including plants. This glycosylation could affect the availability of certain key epitopes either due to masking or misfolding of the protein. Therefore, a non-glycosylated form of pp-PA83 was engineered and produced in N. benthamiana using an in vivo deglycosylation approach based on co-expression of peptide-N-glycosidase F (PNGase F) from Flavobacterium meningosepticum. For comparison, versions of pp-PA83 containing point mutations in six potential N-glycosylation sites were also engineered and expressed in N. benthamiana. The in vivo deglycosylated pp-PA83 (pp-dPA83) was shown to have in vitro activity, in contrast to glycosylated pp-PA83, and to induce significantly higher levels of toxin-neutralizing antibody responses in mice compared with glycosylated pp-PA83, in vitro deglycosylated pp-PA83 or the mutated versions of pp-PA83. These results suggest that pp-dPA83 may offer advantages

  15. Evaluation of Intracellular Signaling Downstream Chimeric Antigen Receptors.

    Hannah Karlsson

    Full Text Available CD19-targeting CAR T cells have shown potency in clinical trials targeting B cell leukemia. Although mainly second generation (2G CARs carrying CD28 or 4-1BB have been investigated in patients, preclinical studies suggest that third generation (3G CARs with both CD28 and 4-1BB have enhanced capacity. However, little is known about the intracellular signaling pathways downstream of CARs. In the present work, we have analyzed the signaling capacity post antigen stimulation in both 2G and 3G CARs. 3G CAR T cells expanded better than 2G CAR T cells upon repeated stimulation with IL-2 and autologous B cells. An antigen-driven accumulation of CAR+ cells was evident post antigen stimulation. The cytotoxicity of both 2G and 3G CAR T cells was maintained by repeated stimulation. The phosphorylation status of intracellular signaling proteins post antigen stimulation showed that 3G CAR T cells had a higher activation status than 2G. Several proteins involved in signaling downstream the TCR were activated, as were proteins involved in the cell cycle, cell adhesion and exocytosis. In conclusion, 3G CAR T cells had a higher degree of intracellular signaling activity than 2G CARs which may explain the increased proliferative capacity seen in 3G CAR T cells. The study also indicates that there may be other signaling pathways to consider when designing or evaluating new generations of CARs.

  16. Evaluation of Intracellular Signaling Downstream Chimeric Antigen Receptors.

    Karlsson, Hannah; Svensson, Emma; Gigg, Camilla; Jarvius, Malin; Olsson-Strömberg, Ulla; Savoldo, Barbara; Dotti, Gianpietro; Loskog, Angelica

    2015-01-01

    CD19-targeting CAR T cells have shown potency in clinical trials targeting B cell leukemia. Although mainly second generation (2G) CARs carrying CD28 or 4-1BB have been investigated in patients, preclinical studies suggest that third generation (3G) CARs with both CD28 and 4-1BB have enhanced capacity. However, little is known about the intracellular signaling pathways downstream of CARs. In the present work, we have analyzed the signaling capacity post antigen stimulation in both 2G and 3G CARs. 3G CAR T cells expanded better than 2G CAR T cells upon repeated stimulation with IL-2 and autologous B cells. An antigen-driven accumulation of CAR+ cells was evident post antigen stimulation. The cytotoxicity of both 2G and 3G CAR T cells was maintained by repeated stimulation. The phosphorylation status of intracellular signaling proteins post antigen stimulation showed that 3G CAR T cells had a higher activation status than 2G. Several proteins involved in signaling downstream the TCR were activated, as were proteins involved in the cell cycle, cell adhesion and exocytosis. In conclusion, 3G CAR T cells had a higher degree of intracellular signaling activity than 2G CARs which may explain the increased proliferative capacity seen in 3G CAR T cells. The study also indicates that there may be other signaling pathways to consider when designing or evaluating new generations of CARs. PMID:26700307

  17. The antigenic structure of the influenza B virus hemagglutinin: operational and topological mapping with monoclonal antibodies.

    Berton, M T; Webster, R G

    1985-06-01

    We have probed the antigenic structure of the influenza B virus hemagglutinin (HA) with monoclonal antibodies specific for the HA of influenza B virus, B/Oregon/5/80. Seventeen laboratory-selected antigenic variants of this virus were analyzed by hemagglutination-inhibition (HI) assays or ELISA and an operational antigenic map was constructed. In addition, the monoclonal antibodies were tested in a competitive binding assay to construct a topological map of the antigenic sites. In contrast to the influenza A virus HA, only a single immunodominant antigenic site composed of several overlapping clusters of epitopes was defined by the HI-positive antibodies. Three variants could be distinguished from the parental virus with polyclonal antisera by HI and infectivity reduction assays suggesting that changes in this antigenic site may be sufficient to provide an epidemiological advantage to influenza B viruses in nature. In addition, two nonoverlapping epitopes of unknown biological significance were identified in the competitive binding analysis by two monoclonal antibodies with no HI activity and little or no neutralizing activity. We previously identified single amino acid substitutions in the HAs of the antigenic variants used in this study (M. T. Berton, C. W. Naeve, and R. G. Webster (1984), J. Virol. 52, 919-927). These changes occurred in regions of the molecule which, by amino acid sequence alignment, appeared to correspond to proposed antigenic sites A and B on the H3 HA of influenza A virus. Correlation with the antigenic map established in this report, however, demonstrates that the amino acid residues actually contribute to a single antigenic site on the influenza B virus HA and suggests significant differences in the antigenic structures of the influenza A and B virus HAs. PMID:2414911

  18. Surface antigen expression and correlation with variable heavy-chain gene mutation status in chronic lymphocytic leukemia.

    Vilpo, Juhani; Tobin, Gerard; Hulkkonen, Janne; Hurme, Mikko; Thunberg, Ulf; Sundström, Christer; Vilpo, Leena; Rosenquist, Richard

    2003-01-01

    Recent studies have demonstrated that B-cell chronic lymphocytic leukemia (CLL) consists of two clinical entities with either somatically hypermutated (M-CLL) or unmutated (UM-CLL) immunoglobulin variable heavy-chain (VH) regions. In view of the fact that the cellular biology of these two subsets of disease is currently unexplored, we performed an extensive analysis of the surface antigen expression and correlated this with the VH gene mutation status in a cohort of 32 CLL patients. Using polymerase chain reaction amplification and nucleotide sequencing, the VH genes were shown to be mutated in 10 cases (31%) and unmutated in 22 (69%). The expression of 27 surface membrane antigens in peripheral blood leukemic cells was analyzed by flow cytometry, measuring both the percentage of positive cells as well as the geometric mean fluorescence intensity (GMF). Most of the surface membrane antigens (CD5, CD11c, CD19, CD20, CD21, CD22, CD23, CD25, CD40, CD45, VD79b, CD80, CD95, CD122, CD124, CD126, CD130, CD154, IgM, and IgD) showed a similar expression pattern in both UM-CLL and M-CLL patients. The similarity of M-CLL and UM-CLL, as demonstrated here for the first time with many protein markers, indicates a considerably homogeneous phenotype in both subsets. Furthermore, CD27 was strongly expressed in all cases, which may suggest a memory cell phenotype for both M-CLL and UM-CLL. More positive cells in the UM-CLL group were observed regarding CD38, but CD38 was not a good predictor of VH gene mutation status. Seventy percent of the M-CLL cases, but only 36% of UM-CLL cases, were Ig-lambda+. The most striking differential expression, however, was observed in the two slicing variants of the common leukocyte antigen CD45, namely CD45RO and CD45RA. CD45RO expression was significantly associated with M-CLL, whereas the GMF intensity of CD45RA tended to be associated with UM-CLL. The role of these CD45 splicing variants in the pathogenesis of CLL deserves further investigation

  19. Activation, Immune Polarization, and Graft-versus-Leukemia Activity of Donor T-cells are Regulated by Specific Subsets of Donor Bone Marrow Antigen-Presenting Cells in Allogeneic Hematopoietic Stem Cell Transplantation1

    Li, Jian-Ming; Southerland, Lauren T.; Lu, Ying; Darlak, Kataryna A.; Giver, Cynthia R.; McMillin, Douglas W.; Harris, Wayne A.C.; Jaye, David L.; Waller, Edmund K.

    2009-01-01

    We investigated the roles of specific subsets of donor APCs purified from bone marrow in donor T cell activation and graft-vs-leukemia (GvL) activity in murine models of hemopoietic stem cell transplantation. Lineage−CD11c+ APC precursors were separated from donor bone marrow based on expression of CD11b. Transplanting lineage−CD11c+CD11b− APC (CD11b− APC) in combination with c-kit+Sca-1+lineage− hemopoietic stem cells (HSC) and congenic donor T cells led to increased donor CD4+ and CD8+ T ce...

  20. THE SEARCH OF OPTIMAL COMBINATION OF ANTIGENS FOR SEROLOGICAL DIAGNOSTICS OF TUBERCULOSIS

    E. V. Vasilyeva

    2013-01-01

    Full Text Available Abstract. The four chimeric recombinant antigens CBD-CFP10, CBD-ESAT6, ESAT6-CFP10 and CBD-P38 contained aminoacid sequences of full-size proteins ESAT6, CFP10 and matured protein P38 of M. tuberculosis, joined with aminoacid sequences of cellulose bind domain of endogluconase A (CBD from Cellumonas fimi have been obtained by gene engineering methods. Recombinant proteins were purified by affine chromatography in column with Ni-NTA-sepharose 6В-CL and as PPDN-3 were used for detection of their antigenic activity in indirect ELISA for TB serological diagnostics. The sera from patients with lung tuberculosis (n = 321, from persons who had professional contacts with TB patients (n = 42, from healthy blood donors (n = 366 and from patients with lung diseases of non-TB etiology were tested. It was detected that there was positive correlation between antibodies level for all studied antigens compared by pair. It has been demonstrated that although antigens were different by antigenic and immunobiological characteristics they add each other in the content of antigenic diagnostics compositions. Thus, all these antigens can be used in the test kits for serological diagnostics of TB. Using of these antigens will allow to detect persons infected by TB and patients with active tuberculosis. 

  1. CD85/LIR-1/ILT2 and CD152 (Cytotoxic T Lymphocyte Antigen 4) Inhibitory Molecules Down-Regulate the Cytolytic Activity of Human CD4+ T-Cell Clones Specific for Mycobacterium tuberculosis

    Merlo, Andrea; Saverino, Daniele; Tenca, Claudya; Grossi, Carlo Enrico; Bruno, Silvia; Ciccone, Ermanno

    2001-01-01

    Antigen-specific cytolytic CD4+ T lymphocytes control Mycobacterium tuberculosis infection by secreting cytokines and by killing macrophages that have phagocytosed the pathogen. However, lysis of the latter cells promotes microbial dissemination, and other macrophages engulf the released bacteria. Subsequently, CD4+ T-cell-mediated killing of macrophages goes on, and this persistent process may hamper control of infection, unless regulatory mechanisms maintain a subtle balance between lysis o...

  2. Engineering antigen-specific immunological tolerance.

    Kontos, Stephan; Grimm, Alizee J.; Hubbell, Jeffrey A.

    2015-05-01

    Unwanted immunity develops in response to many protein drugs, in autoimmunity, in allergy, and in transplantation. Approaches to induce immunological tolerance aim to either prevent these responses or reverse them after they have already taken place. We present here recent developments in approaches, based on engineered peptides, proteins and biomaterials, that harness mechanisms of peripheral tolerance both prophylactically and therapeutically to induce antigenspecific immunological tolerance. These mechanisms are based on responses of B and T lymphocytes to other cells in their immune environment that result in cellular deletion or ignorance to particular antigens, or in development of active immune regulatory responses. Several of these approaches are moving toward clinical development, and some are already in early stages of clinical testing.

  3. Anti-Ia antibody in the sera of normal subjects after in vivo antigenic stimulation

    1982-01-01

    We showed that sera from normal subjects after antigenic challenge with intradermal PPD or Candida antigens or with subcutaneous tetanus vaccine contain a factor that blocks the binding of mouse monoclonal anti-Ia antibody to Ia-positive T cells or to B35 M cells, an Ia- positive human B cell line. The blocking activity appears 48 to 72 h after antigenic challenge and is gone by day 7. The appearance of the anti-Ia blocking activity coincided with a drop in the percentage of Ia- positive T ce...

  4. Antigen-Specific Antibody Glycosylation Is Regulated via Vaccination.

    Alison E Mahan

    2016-03-01

    Full Text Available Antibody effector functions, such as antibody-dependent cellular cytotoxicity, complement deposition, and antibody-dependent phagocytosis, play a critical role in immunity against multiple pathogens, particularly in the absence of neutralizing activity. Two modifications to the IgG constant domain (Fc domain regulate antibody functionality: changes in antibody subclass and changes in a single N-linked glycan located in the CH2 domain of the IgG Fc. Together, these modifications provide a specific set of instructions to the innate immune system to direct the elimination of antibody-bound antigens. While it is clear that subclass selection is actively regulated during the course of natural infection, it is unclear whether antibody glycosylation can be tuned, in a signal-specific or pathogen-specific manner. Here, we show that antibody glycosylation is determined in an antigen- and pathogen-specific manner during HIV infection. Moreover, while dramatic differences exist in bulk IgG glycosylation among individuals in distinct geographical locations, immunization is able to overcome these differences and elicit antigen-specific antibodies with similar antibody glycosylation patterns. Additionally, distinct vaccine regimens induced different antigen-specific IgG glycosylation profiles, suggesting that antibody glycosylation is not only programmable but can be manipulated via the delivery of distinct inflammatory signals during B cell priming. These data strongly suggest that the immune system naturally drives antibody glycosylation in an antigen-specific manner and highlights a promising means by which next-generation therapeutics and vaccines can harness the antiviral activity of the innate immune system via directed alterations in antibody glycosylation in vivo.  .

  5. Antigen-Specific Antibody Glycosylation Is Regulated via Vaccination.

    Mahan, Alison E; Jennewein, Madeleine F; Suscovich, Todd; Dionne, Kendall; Tedesco, Jacquelynne; Chung, Amy W; Streeck, Hendrik; Pau, Maria; Schuitemaker, Hanneke; Francis, Don; Fast, Patricia; Laufer, Dagna; Walker, Bruce D; Baden, Lindsey; Barouch, Dan H; Alter, Galit

    2016-03-01

    Antibody effector functions, such as antibody-dependent cellular cytotoxicity, complement deposition, and antibody-dependent phagocytosis, play a critical role in immunity against multiple pathogens, particularly in the absence of neutralizing activity. Two modifications to the IgG constant domain (Fc domain) regulate antibody functionality: changes in antibody subclass and changes in a single N-linked glycan located in the CH2 domain of the IgG Fc. Together, these modifications provide a specific set of instructions to the innate immune system to direct the elimination of antibody-bound antigens. While it is clear that subclass selection is actively regulated during the course of natural infection, it is unclear whether antibody glycosylation can be tuned, in a signal-specific or pathogen-specific manner. Here, we show that antibody glycosylation is determined in an antigen- and pathogen-specific manner during HIV infection. Moreover, while dramatic differences exist in bulk IgG glycosylation among individuals in distinct geographical locations, immunization is able to overcome these differences and elicit antigen-specific antibodies with similar antibody glycosylation patterns. Additionally, distinct vaccine regimens induced different antigen-specific IgG glycosylation profiles, suggesting that antibody glycosylation is not only programmable but can be manipulated via the delivery of distinct inflammatory signals during B cell priming. These data strongly suggest that the immune system naturally drives antibody glycosylation in an antigen-specific manner and highlights a promising means by which next-generation therapeutics and vaccines can harness the antiviral activity of the innate immune system via directed alterations in antibody glycosylation in vivo.  . PMID:26982805

  6. Effect of particulate adjuvant on the anthrax protective antigen dose required for effective nasal vaccination.

    Bento, Dulce; Staats, Herman F; Borges, Olga

    2015-07-17

    Successful vaccine development is dependent on the development of effective adjuvants since the poor immunogenicity of modern subunit vaccines typically requires the use of potent adjuvants and high antigen doses. In recent years, adjuvant formulations combining both immunopotentiators and delivery systems have emerged as a promising strategy to develop effective and improved vaccines. In this study we investigate if the association of the mast cell activating adjuvant compound 48/80 (C48/80) with chitosan nanoparticles would promote an antigen dose sparing effect when administered intranasally. Even though the induction of strong mucosal immunity required higher antigen doses, incorporation of C48/80 into nanoparticles provided significant dose sparing when compared to antigen and C48/80 in solution with no significant effect on serum neutralizing antibodies titers. These results suggest the potential of this novel adjuvant combination to improve the immunogenicity of a vaccine and decrease the antigen dose required for vaccination. PMID:26087299

  7. Enhanced expression of beta2-microglobulin and HLA antigens on human lymphoid cells by interferon

    Heron, I; Hokland, M; Berg, K

    1979-01-01

    Mononuclear cells from the blood of healthy normal humans were kept in cultures under nonstimulating conditions for 16 hr in the presence or absence of human interferon. The relative quantities of HLA antigens and beta(2)-microglobulin on the cultured cells were determined by quantitative...... immunofluorescence (fluorescence-activated cell sorter) and by the capacity of cells to absorb out cytotoxic antibodies against the relevant antigens. Interferons of different origin and purities enhanced the expression of HLA antigens and beta(2)-microglobulins, whereas membrane immunoglobulins and antigens...... recognized by antiserum raised against human brain and T cells were the same on interferon-treated and control cells. Similar interferon effects were observed on an Epstein-Barrvirus-negative Burkitt lymphoma cell line. The enhanced expression of histocompatibility antigen subsequent to intereferon treatment...

  8. Histocompatibility antigens on astrocytoma cells.

    Hirschberg, H.; Endresen, L I; Wikeby, P

    1982-01-01

    Biopsies tumour cells from astrocytoma-bearing patients were grown in primary culture for 3-5 days. Both low and high grade tumours were represented in the study. The cultured cells could be shown to express the HLA-A and -B antigens using a multispecific allo-antiserum and a rabbit anti-beta-2 microglobulin antibody. The tumour cells were negative for the HLA-DR determinants when tested with either rabbit anti-Ia-like antisera or specific anti-HLA-DR allo-antisera. They also failed to stimul...

  9. Purification and characterization of fetal hematopoietic cells that express the common acute lymphoblastic leukemia antigen (CALLA)

    1983-01-01

    Fetal hematopoietic cells that express the common acute lymphoblastic leukemia antigen (CALLA) were purified from both fetal liver and fetal bone marrow by immune rosetting with sheep erythrocytes coated with rabbit anti-mouse immunoglobulin and by fluorescence-activated cell sorting. Dual fluorescence techniques disclosed that these cells were heterogenous with respect to the expression of a series of differentiation and activation antigens defined by monoclonal antibodies. Thus, whereas all...

  10. The antigenic properties of human prolactin

    The antigenic properties of human prolactin (HPr) were studied using various methods of radio-immuno assay. The homologous system, the difficulty of which resides in the preparation of the tracer, easily permits measurement of physiological levels. In this system, blood prolactin in the monkey has an antigenicity comparable with that of human prolactin, whereas growth hormone and human chorionic somatotropin have feeble or nil antigenic relationship with HPr. Human, sheep and pig prolactins have variable antigenic cross-reactions depending on the immune serum used. These antigenic cross reactions may be applied to the isolation of amniotic prolactin. Human blood prolactin has several components of different molecular weight, but antigenicity comparable with that of pituitary HPr

  11. The antigenicity of tobacco mosaic virus.

    Van Regenmortel, M H

    1999-01-01

    The antigenic properties of the tobacco mosaic virus (TMV) have been studied extensively for more than 50 years. Distinct antigenic determinants called neotopes and cryptotopes have been identified at the surface of intact virions and dissociated coat protein subunits, respectively, indicating that the quaternary structure of the virus influences the antigenic properties. A correlation has been found to exist between the location of seven to ten residue-long continuous epitopes in the TMV coa...

  12. Histocompatibility antigens in coal miners with pneumoconiosis.

    Soutar, C A; Coutts, I.; Parkes, W R; Dodi, I. A.; Gauld, S; Castro, J E; Turner-Warwick, M

    1983-01-01

    Twenty-five histocompatibility antigens have been measured in 100 coal miners with pneumoconiosis attending a pneumoconiosis medical panel and the results compared with a panel of 200 normal volunteers not exposed to dust. Chest radiographs were read independently by three readers according to the ILO U/C classification. On a combined score, 40 men were thought to have simple pneumoconiosis and 60 men complicated pneumoconiosis. The number of antigens tested and associations between antigens ...

  13. Isolation of Fasciola hepatica tegument antigens.

    Hillyer, G. V.

    1980-01-01

    Fasciola hepatica tegument antigens were isolated from intact worms in the cold by using Nonidet P-40. Proof of the tegumental nature of the antigens was shown by the peroxidase-antiperoxidase immunocytochemical technique at the light microscope level. The potential of F. hepatica tegument antigens for the immunodiagnosis of rabbit and human fascioliasis was shown by Ouchterlony immunodiffusion, although cross-reactivity was evident in one of six serum samples from patients infected with Schi...

  14. Enhanced T cell responses to antigenic peptides targeted to B cell surface Ig, Ia, or class I molecules

    1988-01-01

    The helper T cell recognition of soluble globular protein antigens requires that the proteins be processed by an APC, releasing a peptide that is transported to and held on the APC surface where it is recognized by the specific T cell in conjunction with Ia. When cellular processing functions are blocked, APC lose their ability to present native antigens while retaining the capacity to activate T cells when provided with a cognate peptide fragment that contains the T cell antigenic determinan...

  15. Analysis of expression profiles of MAGE-A antigens in oral squamous cell carcinoma cell lines

    Reichert Torsten E

    2009-04-01

    Full Text Available Abstract Background The immunological response to solid tumours is insufficient. Therefore, tumour specific antigens have been explored to facilitate the activation of the immune system. The cancer/testis antigen class of MAGE-A antigens is a possible target for vaccination. Their differential expression profiles also modulate the course of the cancer disease and its response to antineoplastic drugs. Methods The expression profiles of MAGE-A2, -A3, -A4, -A6 and -A10 in five own oral squamous cell carcinoma cell lines were characterised by rt-PCR, qrt-PCR and immunocytochemistry with a global MAGE-A antibody (57B and compared with those of an adult keratinocyte cell line (NHEK. Results All tumour cell lines expressed MAGE-A antigens. The antigens were expressed in groups with different preferences. The predominant antigens expressed were MAGE-A2, -A3 and -A6. MAGE-A10 was not expressed in the cell lines tested. The MAGE-A gene products detected in the adult keratinocyte cell line NHEK were used as a reference. Conclusion MAGE-A antigens are expressed in oral squamous cell carcinomas. The expression profiles measured facilitate distinct examinations in forthcoming studies on responses to antineoplastic drugs or radiation therapy. MAGE-A antigens are still an interesting aim for immunotherapy.

  16. Development of recombinant antigen array for simultaneous detection of viral antibodies.

    Yi Liu

    Full Text Available Protein microarrays have been developed to study antibody reactivity against a large number of antigens, demonstrating extensive perspective for clinical application. We developed a viral antigen array by spotting four recombinant antigens and synthetic peptide, including glycoprotein G of herpes simplex virus (HSV type 1 and 2, phosphoprotein 150 of cytomegalovirus (CMV, Rubella virus (RV core plus glycoprotein E1 and E2 as well as a E1 peptide with the optimal concentrations on activated glass slides to simultaneously detect IgG and IgM against HSV1, HSV2, CMV and RV in clinical specimens of sera and cerebrospinal fluids (CSFs. The positive reference sera were initially used to measure the sensitivity and specificity of the array with the optimal conditions. Then clinical specimens of 144 sera and 93 CSFs were tested for IgG and IgM antibodies directed against HSV1, HSV2, CMV and RV by the antigen array. Specificity of the antigen array for viral antibodies detection was satisfying compared to commercial ELISA kits but sensitivity of the array varied relying on quality and antigenic epitopes of the spotting antigens. In short, the recombinant antigen array has potential to simultaneous detect multiple viral antibodies using minute amount (3 µl of samples, which holds the particularly advantage to detect viral antibodies in clinical CSFs being suspicious of neonatal meningitis and encephalitis.

  17. Concerted activity of IgG1 antibodies and IL-4/IL-25-dependent effector cells trap helminth larvae in the tissues following vaccination with defined secreted antigens, providing sterile immunity to challenge infection.

    James P Hewitson

    2015-03-01

    Full Text Available Over 25% of the world's population are infected with helminth parasites, the majority of which colonise the gastrointestinal tract. However, no vaccine is yet available for human use, and mechanisms of protective immunity remain unclear. In the mouse model of Heligmosomoides polygyrus infection, vaccination with excretory-secretory (HES antigens from adult parasites elicits sterilising immunity. Notably, three purified HES antigens (VAL-1, -2 and -3 are sufficient for effective vaccination. Protection is fully dependent upon specific IgG1 antibodies, but passive transfer confers only partial immunity to infection, indicating that cellular components are also required. Moreover, immune mice show greater cellular infiltration associated with trapping of larvae in the gut wall prior to their maturation. Intra-vital imaging of infected intestinal tissue revealed a four-fold increase in extravasation by LysM+GFP+ myeloid cells in vaccinated mice, and the massing of these cells around immature larvae. Mice deficient in FcRγ chain or C3 complement component remain fully immune, suggesting that in the presence of antibodies that directly neutralise parasite molecules, the myeloid compartment may attack larvae more quickly and effectively. Immunity to challenge infection was compromised in IL-4Rα- and IL-25-deficient mice, despite levels of specific antibody comparable to immune wild-type controls, while deficiencies in basophils, eosinophils or mast cells or CCR2-dependent inflammatory monocytes did not diminish immunity. Finally, we identify a suite of previously uncharacterised heat-labile vaccine antigens with homologs in human and veterinary parasites that together promote full immunity. Taken together, these data indicate that vaccine-induced immunity to intestinal helminths involves IgG1 antibodies directed against secreted proteins acting in concert with IL-25-dependent Type 2 myeloid effector populations.

  18. Activation of a heterogeneous hepatitis B (HB) core and e antigen-specific CD4+ T-cell population during seroconversion to anti-HBe and anti-HBs in hepatitis B virus infection.

    Jung, M C; Diepolder, H M; Spengler, U; Wierenga, E A; Zachoval, R; Hoffmann, R M; Eichenlaub, D; Frösner, G; Will, H; Pape, G. R.

    1995-01-01

    Overcoming hepatitis B virus infection essentially depends on the appropriate immune response of the infected host. Among the hepatitis B virus antigens, the core (HBcAg) and e (HBeAg) proteins appear highly immunogenic and induce important lymphocyte effector functions. In order to investigate the importance of HBcAg/HBeAg-specific T lymphocytes in patients with acute and chronic hepatitis B and to identify immunodominant epitopes within the HBcAg/HBeAg, CD4+ T-cell responses to hepatitis B ...

  19. Urinary IgG antibody against mixed heat-killed coliform antigen and lipopolysaccharide core antigen.

    Gibb, A P; Edmond, D. M.

    1992-01-01

    AIMS: To determine whether antibody to lipopolysaccharide-core (LPS-core) antigen is an important component of the antibody, detected by mixed heat-killed coliform antigen, in urine from patients with suspected urinary tract infection. METHODS: LPS-core antigen and mixed heat-killed coliform antigen were used in an enzyme linked immunosorbent assay (ELISA) to measure IgG antibody in midstream urine samples. Seventy two samples from students attending their general practitioner with symptoms s...

  20. Combination of cancer antigen 125 and carcinoembryonic antigen can improve ovarian cancer diagnosis

    Sørensen, Sofie Sølvsten; Mosgaard, Berit Jul

    2011-01-01

    The purpose of the present study was to evaluate the ability of the tumour marker carcinoembryonic antigen (CEA) in combination with cancer antigen 125 (CA-125) to differentiate between malignant ovarian and malignant non-ovarian disease.......The purpose of the present study was to evaluate the ability of the tumour marker carcinoembryonic antigen (CEA) in combination with cancer antigen 125 (CA-125) to differentiate between malignant ovarian and malignant non-ovarian disease....

  1. Evidence for horizontal gene transfer of two antigenically distinct O antigens in Bordetella bronchiseptica

    Antigenic variation is one mechanism pathogens use to avoid immune-mediated competition between closely related strains. Here, we show that two Bordetella bronchiseptica strains, RB50 and 1289, express two antigenically distinct O-antigen serotypes (O1 and O2 respectively). When 18 additional B. b...

  2. An efficient antigene activity and antiproliferative effect by targeting the Bcl-2 or survivin gene with triplex forming oligonucleotides containing a W-shaped nucleoside analogue (WNA-βT).

    Taniguchi, Yosuke; Sasaki, Shigeki

    2012-10-01

    Triplex forming oligonucleotides (TFOs) are some of the most promising tools in the antigene strategy for the development of gene targeting therapeutics. However, the stable triplex formation is restricted to the homopurine sequences consisting of purine nucleosides, dG and dA. Therefore, the T or dC nucleoside in the homopurine strand inhibits the stable triplex formation. We have developed W-shaped nucleoside analogues (WNAs) for the formation of the unnatural type triplex DNA, with sequences containing the interrupting site in an antiparallel triplex formation. In the present study, we tested the antigene effect of TFOs having WNA-βT, which increased the stability of the triplex formation with a target sequence including the TA interrupting site. We designed the GU TFO (WNA) and GU TFO (natural) for targeting sequences of the Bcl-2 or survivin oncogene. The gel shift assay showed that the TFO (WNA) formed more stable triplexes than the natural TFO. Remarkably, the Bcl-2- or survivin-targeted TFO (WNA) inhibited the cell proliferation and induced a caspase-dependent apoptosis. It was confirmed that the survivin-targeted TFO (WNA) more effectively decreased the number of survivin products in the A549 cell than the natural TFOs. PMID:22987068

  3. Dichotomy of the human T cell response to Leishmania antigens. I. Th1-like response to Leishmania major promastigote antigens in individuals recovered from cutaneous leishmaniasis

    Kemp, M; Hey, A S; Kurtzhals, J A;

    1994-01-01

    The T cell response to antigens from Leishmania major promastigotes was investigated in peripheral blood mononuclear cells from Sudanese individuals with a history of cutaneous leishmaniasis (CL), Sudanese individuals with positive DTH reaction in the leishmanin skin test but with no history...... of skin lesions, and in Danes without known exposure to Leishmania parasites. Proliferation and production of interferon-gamma (IFN-gamma) and IL-4 in antigen-stimulated cultures was measured. Lymphocytes from individuals with a history of CL proliferated vigorously and produced IFN-gamma after...... the unexposed Danes were not activated by gp63. The cells from Danish donors produced either IFN-gamma or IL-4, but not both cytokines after incubation with the crude preparation of L. major antigens. The data show that the T cell response to Leishmania antigens in humans who have had uncomplicated CL...

  4. Biological function and molecular mapping of M antigen in yeast phase of Histoplasma capsulatum.

    Allan Jefferson Guimarães

    Full Text Available Histoplasmosis, due to the intracellular fungus Histoplasma capsulatum, can be diagnosed by demonstrating the presence of antibodies specific to the immunodominant M antigen. However, the role of this protein in the pathogenesis of histoplasmosis has not been elucidated. We sought to structurally and immunologically characterize the protein, determine yeast cell surface expression, and confirm catalase activity. A 3D-rendering of the M antigen by homology modeling revealed that the structures and domains closely resemble characterized fungal catalases. We generated monoclonal antibodies (mAbs to the protein and determined that the M antigen is present on the yeast cell surface and in cell wall/cell membrane preparations. Similarly, we found that the majority of catalase activity was in extracts containing fungal surface antigens and that the M antigen is not significantly secreted by live yeast cells. The mAbs also identified unique epitopes on the M antigen. The localization of the M antigen to the cell surface of H. capsulatum yeast and the characterization of the protein's major epitopes have important implications since it demonstrates that although the protein may participate in protecting the fungus against oxidative stress it is also accessible to host immune cells and antibody.

  5. γδ T cells recognize a microbial encoded B cell antigen to initiate a rapid antigen specific Interleukin 17 response

    Zeng, Xun; Wei, Yu-ling; Huang, Jun; Newell, Evan W.; Yu, Hongxiang; Kidd, Brian A.; Kuhns, Michael S.; Waters, Ray W.; Davis, Mark M.; Weaver, Casey T.; Chien, Yueh-hsiu

    2012-01-01

    Summary γδ T cells contribute uniquely to host immune defense. However, how they function remains an enigma. Although it is unclear what most γδ T cells recognize, common dogma asserts that they recognize self-antigens. While they are the major initial Interleukin-17 (IL-17) producers in infections, it is unclear what is required to trigger these cells to act. Here, we report that a noted B cell antigen, the algae protein-phycoerythrin (PE) is an antigen for murine and human γδ T cells. PE also stained specific bovine γδ T cells. Employing this specificity, we demonstrated that antigen recognition, but not extensive clonal expansion, was required to activate naïve γδ T cells to make IL-17. In this activated state, γδ T cells gained the ability to respond to cytokine signals that perpetuated the IL-17 production. These results underscore the adaptability of lymphocyte antigen receptors and suggest a previously unrecognized antigen-driven rapid response in protective immunity prior to the maturation of classical adaptive immunity. PMID:22960222

  6. Interferon-induced changes in expression of antigens defined by monoclonal antibodies on malignant and nonmalignant mononuclear hematopoietic cells

    Hokland, M; Ritz, J; Hokland, P

    1983-01-01

    HLA-antigens detected by beta 2-Microglobulin (beta 2-M) could be demonstrated for peripheral blood mononuclear cells, non-T cells, Null cells, activated T cells, fetal thymocytes, adherent cells, and on four malignant non-T lymphoblastoid cell lines. In contrast, no significant differences were...... number as well as the amount of lymphocytes expressing the T10 antigen. It thus seems that the enhancing effect of IFN on resting cells of the immune system is highly selective. On the four lymphoblastoid cell lines, the expression of the common acute lymphoblastic leukemia antigen (CALLA) was...... significantly decreased concomitantly with the increase in MHC-antigens. On the other hand, the density of both a HLA-D related Ia antigen (I2) and a B-lymphocyte differentiation antigen (B1) remained unaltered following IFN treatment. The implications of these findings are discussed. Udgivelsesdato: 1983-null...

  7. Adsorption of multimeric T cell antigens on carbon nanotubes

    Fadel, Tarek R; Li, Nan; Shah, Smith;

    2013-01-01

    Antigen-specific activation of cytotoxic T cells can be enhanced up to three-fold more than soluble controls when using functionalized bundled carbon nanotube substrates ((b) CNTs). To overcome the denaturing effects of direct adsorption on (b) CNTs, a simple but robust method is demonstrated to...... stabilize the T cell stimulus on carbon nanotube substrates through non-covalent attachment of the linker neutravidin....

  8. Trafficking of B cell antigen in lymph nodes

    Gonzalez, Santiago F.; Degn, Søren Egedal; Pitcher, Lisa A.; Woodruff, Matthew; Heesters, Balthasar A.; Carroll, Michael C.

    2011-01-01

    The clonal selection theory first proposed by Macfarlane Burnet is a cornerstone of immunology ( 1 ). At the time, it revolutionized the thinking of immunologists because it provided a simple explanation for lymphocyte specificity, immunological memory, and elimination of self-reactive clones ( 2...... microscopy ( 4, 5 ) have provided new insights into the trafficking of B cells and their antigen. In this review, we summarize these advances in the context of our current view of B cell circulation and activation....

  9. Liver disease and the e antigen in HBsAg carriers with chronic renal failure.

    Coughlin, G P; Van Deth, A G; Disney, A P; Van Hay, J.; Wangel, A. G.

    1980-01-01

    This study was undertaken to assess the frequency of development and the stages of evolution of chronic liver disease in patients with renal failure who are chronic carriers of hepatitis B surface antigen. Cirrhosis or chronic active hepatitis developed in five of 21 patients and could not be predicted by the initial histological appearance or by HLA-A and B typing but was associated with the e antigen in four of the five patients. However, the antigen was not a consistent indicator of a poor...

  10. O-antigen protects gram-negative bacteria from histone killing.

    Catherine Chaput

    Full Text Available Beyond their traditional role of wrapping DNA, histones display antibacterial activity to Gram-negative and -positive bacteria. To identify bacterial components that allow survival to a histone challenge, we selected resistant bacteria from homologous Escherichia coli libraries that harbor plasmids carrying pieces of the chromosome in different sizes. We identified genes required for exopolysaccharide production and for the synthesis of the polysaccharide domain of the lipopolysaccharide, called O-antigen. Indeed, O-antigen and exopolysaccharide conferred further resistance to histones. Notably, O-antigen also conferred resistance to histones in the pathogens Shigella flexneri and Klebsiella pneumoniae.

  11. How T-cells use large deviations to recognize foreign antigens

    Zint, Natali; Hollander, Frank den

    2008-01-01

    A stochastic model for the activation of T-cells is analysed. T-cells are part of the immune system and recognize foreign antigens against a background of the body's own molecules. The model under consideration is a slight generalization of a model introduced by Van den Berg, Rand and Burroughs in 2001, and is capable of explaining how this recognition works on the basis of rare stochastic events. With the help of a refined large deviation theorem and numerical evaluation it is shown that, for a wide range of parameters, T-cells can distinguish reliably between foreign antigens and self-antigens.

  12. Induction of HLA-DR antigen on human squamous carcinoma by recombinant interferon gamma.

    Koch, W M; Dugan, E; Diaz, L A; Richtsmeier, W J

    1988-05-01

    The antigen recognition system which plays the major role in immunologic attraction mechanisms, including graft rejection, is the class II major histocompatibility complex containing the HLA-DR locus. Few types of cells constitutively express this antigen, as it is a potent immunological activating signal usually confined to antigen processing cells, activated lymphocytes, and endothelium. Using indirect immunofluorescence, we have observed induction of the HLA-DR glycoprotein in selected head and neck squamous cell carcinoma tissue cultures treated with recombinant interferon gamma. This occurs in concert with growth arrest and morphological changes after rHuIFN-gamma treatment. This report describes the induction of a surface antigen that may have profound prognostic significance. Understanding the kinetics of HLA-DR induction will aid in the design and assessment of adoptive immunotherapy with rHuIFN-gamma. PMID:3129628

  13. Review of Mycobacteriumavium subsp. paratuberculosis antigen candidates with diagnostic potential

    Mikkelsen, Heidi; Aagaard, Claus; Nielsen, Søren Saxmose; Jungersen, Gregers

    development of antibodies and shedding of detectable amounts of MAP. At present, available diagnostic assays are limited by the lack of MAP specific antigens included in these assays resulting in poor specificity. The objective of this review is to provide a systematic overview of diagnostic MAP antigen...... candidates described to date with special emphasis on antigen candidates tested for CMI responses. Relevant information on 115 different MAP antigens was systematically extracted from literature and summarized in 6 tables of CMI antigens, secreted antigens, cell wall and membrane antigens, lipoprotein...... antigens, heat shock antigens and hypothetical antigens. Strategies for evaluation of novel antigen candidates are discussed critically. Relatively few of the described antigens were evaluated for their use in CMI based diagnostic assays and so far, no obvious candidate has been identified for this...

  14. Distinct roles for histone methyltransferases G9a and GLP in cancer germline antigen gene regulation in human cancer cells and murine ES cells

    Link, Petra A.; Gangisetty, Omkaram; James, Smitha R.; Woloszynska-Read, Anna; Tachibana, Makoto; Shinkai, Yoichi; Karpf, Adam R.

    2009-01-01

    The H3K9me2 histone methyltransferases G9a and GLP repress Mage-a class cancer germline (CG) antigen gene expression in murine ES cells but the role of these enzymes in CG antigen gene regulation in human cancer cells is unknown. Here we show that while independent or dual knockdown of G9a and GLP in human cancer cells leads to reduced global and CG antigen promoter-associated H3K9me2 levels it does not activate CG antigen gene expression. Moreover, CG antigen gene repression is maintained fo...

  15. Neurofibromatosis type 2 tumor suppressor protein, NF2, induces proteasome-mediated degradation of JC virus T-antigen in human glioblastoma.

    Sarah Beltrami

    Full Text Available Neurofibromatosis type 2 protein (NF2 has been shown to act as tumor suppressor primarily through its functions as a cytoskeletal scaffold. However, NF2 can also be found in the nucleus, where its role is less clear. Previously, our group has identified JC virus (JCV tumor antigen (T-antigen as a nuclear binding partner for NF2 in tumors derived from JCV T-antigen transgenic mice. The association of NF2 with T-antigen in neuronal origin tumors suggests a potential role for NF2 in regulating the expression of the JCV T-antigen. Here, we report that NF2 suppresses T-antigen protein expression in U-87 MG human glioblastoma cells, which subsequently reduces T-antigen-mediated regulation of the JCV promoter. When T-antigen mRNA was quantified, it was determined that increasing expression of NF2 correlated with an accumulation of T-antigen mRNA; however, a decrease in T-antigen at the protein level was observed. NF2 was found to promote degradation of ubiquitin bound T-antigen protein via a proteasome dependent pathway concomitant with the accumulation of the JCV early mRNA encoding T-antigen. The interaction between T-antigen and NF2 maps to the FERM domain of NF2, which has been shown previously to be responsible for its tumor suppressor activity. Co-immunoprecipitation assays revealed a ternary complex among NF2, T-antigen, and the tumor suppressor protein, p53 within a glioblastoma cell line. Further, these proteins were detected in various degrees in patient tumor tissue, suggesting that these associations may occur in vivo. Collectively, these results demonstrate that NF2 negatively regulates JCV T-antigen expression by proteasome-mediated degradation, and suggest a novel role for NF2 as a suppressor of JCV T-antigen-induced cell cycle regulation.

  16. Further characterization of filarial antigens by SDS polyacrylamide gel electrophoresis

    Dissanayake, S.; Galahitiyawa, S. C.; Ismail, M. M.

    1983-01-01

    SDS (sodium dodecyl sulfate)-polyacrylamide gel electrophoresis of an antigen isolated from sera of Wuchereria bancrofti-infected patients and Setaria digitata antigen SD2-4 is reported. Both antigens showed carbohydrate (glycoprotein) staining. The W. bancrofti antigen had an apparent relative molecular mass of 35 000 while the S. digitata antigen SD2-4 migrated at the marker dye position on SDS-polyacrylamide gel electrophoresis. SDS treatment of these antigens did not abolish the precipita...

  17. Selective expression and immunogenicity of the cancer/testis antigens SP17, AKAP4 and PTTG1 in non-small cell lung cancer: new candidates for active immunotherapy.

    Chiriva-Internati, Maurizio; Mirandola, Leonardo; Figueroa, Jose A; Yu, Yuefei; Grizzi, Fabio; Kim, Minji; Jenkins, Marjorie; Cobos, Everardo; Jumper, Cynthia; Alalawi, Raed

    2014-05-01

    ABSTRACT BACKGROUND. Lung cancer is the leading cause of cancer deaths in both genders worldwide, with an incidence only second to prostate cancer in men and breast cancer in women. The lethality of the disease highlights the urgent need for innovative therapeutic options. Immunotherapy can afford efficient and specific targeting of tumor cells, improving efficacy and reducing the side effects of current therapies. We have previously reported the aberrant expression of cancer/testis antigens (CTAs) in tumors of unrelated histological origin. In this study we investigated the expression and immunogenicity of the cancer/testis antigens (CTAs) Sperm Protein 17 (SP17), A-kinase anchor protein 4 (AKAP4) and Pituitary Tumor Transforming Gene 1 (PTTG1) in human non-small cell lung cancer (NSCLC) cell lines and primary tumors. METHODS. We used RT-PCR, immunofluorescence, flow cytometry, ELISA and cytotoxicity assays to determine the expression levels and immunogenicity of SP17, AKAP4 and PTTG1 in human NSCLC cell lines and primary tumors. RESULTS. We found that SP17, AKAP4 and PTTG1 are aberrantly expressed in NSCLC cancer cell lines and primary tumor tissues from patients, compared to normal lung cell lines and tissues. We established the immunogenicity of these CTAs by measuring CTA-specific autoantibodies in patients' sera and generating CTA-specific autologous cytotoxic lymphocytes (CTLs) from patients' peripheral blood mononuclear cells (PBMCs). CONCLUSIONS. Our results provide proof of principle that the CTAs SP17/AKAP4/PTTG1 are expressed in both human NSCLC cell lines and primary tumors and can elicit an immunogenic response in NSCLC patients. Based on our findings, further studies are warranted to explore the feasibility of developing CTA-specific immunotherapeutic strategies for NSCLC patients. PMID:24811938

  18. Microsomal triglyceride transfer protein lipidation and control of CD1d on antigen-presenting cells

    Dougan, Stephanie K.; Salas, Azucena; Rava, Paul; Agyemang, Amma; Kaser, Arthur; Morrison, Jamin; Khurana, Archana; Kronenberg, Mitchell; Johnson, Caroline; Exley, Mark; Hussain, M. Mahmood; Blumberg, Richard S.

    2005-01-01

    Microsomal triglyceride transfer protein (MTP), an endoplasmic reticulum (ER) chaperone that loads lipids onto apolipoprotein B, also regulates CD1d presentation of glycolipid antigens in the liver and intestine. We show MTP RNA and protein in antigen-presenting cells (APCs) by reverse transcription–polymerase chain reaction and by immunoblotting of mouse liver mononuclear cells and mouse and human B cell lines. Functional MTP, demonstrated by specific triglyceride transfer activity, is prese...

  19. Immunohistochemical localization of granzyme B antigen in cytotoxic cells in human tissues.

    Hameed, A.; Truong, L D; Price, V; Kruhenbuhl, O.; Tschopp, J

    1991-01-01

    Human granzyme B antigen is expressed in cytoplasmic granules of activated cytotoxic T lymphocytes and natural killer cells. Recombinant granzyme B was generated using a prokaryotic expression vector under the control of T7 transcription and translation signals. The 25-kd recombinant protein (granzyme B) was used to develop a rabbit polyclonal antiserum. Purified anti-granzyme B antibodies were used to detect the antigen expression in cytotoxic cells in human tissues. Using the avidin-biotin-...

  20. Modification of the lipid moiety of the enterobacterial common antigen by the "Pseudomonas factor".

    Kuhn, H M; Neter, E; Mayer, H

    1983-01-01

    Pseudomonas aeruginosa produces a factor (PF) which affects the enterobacterial common antigen (ECA); resulting in failure of the antigen to modify erythrocytes for hemagglutination by ECA antibodies. In the present study the nature of PF was determined. Pronase treatment abolished its activity, indicating the protein nature of PF. PF-treated ECA no longer coated erythrocytes but still reacted with ECA antibodies in immunoelectrophoresis tests with monospecific antiserum to ECA, although diff...

  1. Biological Function and Molecular Mapping of M Antigen in Yeast Phase of Histoplasma capsulatum

    Guimarães, Allan Jefferson; Hamilton, Andrew John; de M. Guedes, Herbert Leonel; Nosanchuk, Joshua Daniel; Zancopé-Oliveira, Rosely Maria

    2008-01-01

    Histoplasmosis, due to the intracellular fungus Histoplasma capsulatum, can be diagnosed by demonstrating the presence of antibodies specific to the immunodominant M antigen. However, the role of this protein in the pathogenesis of histoplasmosis has not been elucidated. We sought to structurally and immunologically characterize the protein, determine yeast cell surface expression, and confirm catalase activity. A 3D-rendering of the M antigen by homology modeling revealed that the structures...

  2. Tumor antigen specific iTreg accumulate in the tumor microenvironment and suppress therapeutic vaccination

    Schreiber, Taylor H; Wolf, Dietlinde; Bodero, Maria; Podack, Eckhard

    2012-01-01

    Tumor specific antigens (TSA) provide an opportunity to mobilize therapeutic immune responses against cancer. To evade such responses, tumor development in immunocompetent hosts is accompanied by acquisition of both active and passive mechanisms of immune suppression, including recruitment of CD4+FoxP3+ regulatory T cells (Treg). Thymic derived Treg (nTreg) may recognize self-antigens in the tumor microenvironment, while peripherally induced Treg (iTreg) may preferentially recognize the same ...

  3. γδ T cells recognize a microbial encoded B cell antigen to initiate a rapid antigen-specific interleukin-17 response.

    Zeng, Xun; Wei, Yu-Ling; Huang, Jun; Newell, Evan W; Yu, Hongxiang; Kidd, Brian A; Kuhns, Michael S; Waters, Ray W; Davis, Mark M; Weaver, Casey T; Chien, Yueh-hsiu

    2012-09-21

    γδ T cells contribute uniquely to immune competence. Nevertheless, how they function remains an enigma. It is unclear what most γδ T cells recognize, what is required for them to mount an immune response, and how the γδ T cell response is integrated into host immune defense. Here, we report that a noted B cell antigen, the algae protein phycoerythrin (PE), is a murine and human γδ T cell antigen. Employing this specificity, we demonstrated that antigen recognition activated naive γδ T cells to make interleukin-17 and respond to cytokine signals that perpetuate the response. High frequencies of antigen-specific γδ T cells in naive animals and their ability to mount effector response without extensive clonal expansion allow γδ T cells to initiate a swift, substantial response. These results underscore the adaptability of lymphocyte antigen receptors and suggest an antigen-driven rapid response in protective immunity prior to the maturation of classical adaptive immunity. PMID:22960222

  4. Galactosylated LDL nanoparticles: a novel targeting delivery system to deliver antigen to macrophages and enhance antigen specific T cell responses

    Wu, Fang; Wuensch, Sherry A.; Azadniv, Mitra; Ebrahimkhani, Mohammad R.; Crispe, I. Nicholas

    2009-01-01

    We aim to define the role of Kupffer cells in intrahepatic antigen presentation, using the selective delivery of antigen to Kupffer cells rather than other populations of liver antigen-presenting cells. To achieve this we developed a novel antigen delivery system that can target antigens to macrophages, based on a galactosylated low-density lipoprotein nano-scale platform. Antigen was delivered via the galactose particle receptor (GPr), internalized, degraded and presented to T cells. The con...

  5. Targeting tumor antigens to secreted membrane vesicles in vivo induces efficient antitumor immune responses.

    Zeelenberg, I.S.; Ostrowski, M.; Krumeich, S.; Bobrie, A.; Jancic, C.; Boissonnas, A.; Delcayre, A.; Pecq, JB Le; Combadiere, B.; Amigorena, S.; Thery, C.

    2008-01-01

    Expression of non-self antigens by tumors can induce activation of T cells in vivo, although this activation can lead to either immunity or tolerance. CD8+ T-cell activation can be direct (if the tumor expresses MHC class I molecules) or indirect (after the capture and cross-presentation of tumor an

  6. Barriers to antigenic escape by pathogens: trade-off between reproductive rate and antigenic mutability

    Bush Robin M

    2007-11-01

    Full Text Available Abstract Background A single measles vaccination provides lifelong protection. No antigenic variants that escape immunity have been observed. By contrast, influenza continually evolves new antigenic variants, and the vaccine has to be updated frequently with new strains. Both measles and influenza are RNA viruses with high mutation rates, so the mutation rate alone cannot explain the differences in antigenic variability. Results We develop a new hypothesis to explain antigenic stasis versus change. We first note that the antigenically static viruses tend to have high reproductive rates and to concentrate infection in children, whereas antigenically variable viruses such as influenza tend to spread more widely across age classes. We argue that, for pathogens in a naive host population that spread more rapidly in younger individuals than in older individuals, natural selection weights more heavily a rise in reproductive rate. By contrast, pathogens that spread more readily among older individuals gain more by antigenic escape, so natural selection weights more heavily antigenic mutability. Conclusion These divergent selective pressures on reproductive rate and antigenic mutability may explain some of the observed differences between pathogens in age-class bias, reproductive rate, and antigenic variation.

  7. Hepatitis B virus antigens impair NK cell function.

    Yang, Yinli; Han, Qiuju; Zhang, Cai; Xiao, Min; Zhang, Jian

    2016-09-01

    An inadequate immune response of the host is thought to be a critical factor causing chronic hepatitis B virus (CHB) infection. Natural killer (NK) cells, as one of the key players in the eradication and control of viral infections, were functionally impaired in CHB patients, which might contribute to viral persistence. Here, we reported that HBV antigens HBsAg and HBeAg directly inhibited NK cell function. HBsAg and/or HBeAg blocked NK cell activation, cytokine production and cytotoxic granule release in human NK cell-line NK-92 cells, which might be related to the downregulation of activating receptors and upregulation of inhibitory receptor. Furthermore, the underlying mechanisms likely involved the suppression of STAT1, NF-κB and p38 MAPK pathways. These findings implicated that HBV antigen-mediated inhibition of NK cells might be an efficient strategy for HBV evasion, targeting the early antiviral responses mediated by NK cells and resulting in the establishment of chronic virus infection. Therefore, this study revealed the relationship between viral antigens and human immune function, especially a potential important interaction between HBV and innate immune responses. PMID:27341035

  8. Antigen specificity can be irrelevant to immunocytokine efficacy and biodistribution.

    Tzeng, Alice; Kwan, Byron H; Opel, Cary F; Navaratna, Tejas; Wittrup, K Dane

    2015-03-17

    Cytokine therapy can activate potent, sustained antitumor responses, but collateral toxicity often limits dosages. Although antibody-cytokine fusions (immunocytokines) have been designed with the intent to localize cytokine activity, systemic dose-limiting side effects are not fully ameliorated by attempted tumor targeting. Using the s.c. B16F10 melanoma model, we found that a nontoxic dose of IL-2 immunocytokine synergized with tumor-specific antibody to significantly enhance therapeutic outcomes compared with immunocytokine monotherapy, concomitant with increased tumor saturation and intratumoral cytokine responses. Examination of cell subset biodistribution showed that the immunocytokine associated mainly with IL-2R-expressing innate immune cells, with more bound immunocytokine present in systemic organs than the tumor microenvironment. More surprisingly, immunocytokine antigen specificity and Fcγ receptor interactions did not seem necessary for therapeutic efficacy or biodistribution patterns because immunocytokines with irrelevant specificity and/or inactive mutant Fc domains behaved similarly to tumor-specific immunocytokine. IL-2-IL-2R interactions, rather than antibody-antigen targeting, dictated immunocytokine localization; however, the lack of tumor targeting did not preclude successful antibody combination therapy. Mathematical modeling revealed immunocytokine size as another driver of antigen targeting efficiency. This work presents a safe, straightforward strategy for augmenting immunocytokine efficacy by supplementary antibody dosing and explores underappreciated factors that can subvert efforts to purposefully alter cytokine biodistribution. PMID:25733854

  9. A rapid radioimmunoassay for determination of tumor antigens with reference to carcinoembryonic antigen

    A novel experimental procedure for the determination of carcinoembryonic antigen (CEA) by a solid phase microradioimmunoassay has been developed. Goat anti-CEA antibodies were immobilized by coupling to cyanogen bromide activated filter paper discs. The inhibition of binding of radioiodinated CEA to the discs was proportional to the amount of unlabelled CEA present in the test sample. The experimental procedure involved two steps: (i) the test material containing unlabelled CEA was allowed to react with the antibody coated discs at 37 deg C for 2 hrs., and (ii) a standard amount of 125I-CEA was added to the reaction mixture and incubated for 24 hours at 37 deg C or room temperature. The discs were then washed 4 times and the radioactivity of each disc was determined. The sensitivity of the test in its present state of development was 2.5 ng/ml. (author)

  10. Harnessing Dendritic Cells for Tumor Antigen Presentation

    Dendritic cells (DC) are professional antigen presenting cells that are crucial for the induction of anti-tumor T cell responses. As a consequence, research has focused on the harnessing of DCs for therapeutic interventions. Although current strategies employing ex vivo-generated and tumor-antigen loaded DCs have been proven feasible, there are still many obstacles to overcome in order to improve clinical trial successes and offset the cost and complexity of customized cell therapy. This review focuses on one of these obstacles and a pivotal step for the priming of tumor-specific CD8+ and CD4+ T cells; the in vitro loading of DCs with tumor antigens

  11. Cell surface antigens of radiation leukemia virus-induced BALB/c leukemias defined by syngeneic cytotoxic T lymphocytes

    Two cell surface antigens of mouse leukemias were defined by BALB/c cytotoxic T lymphocytes (CTL) generated against syngeneic radiation leukemia virus (RadLV)-induced leukemia, BALBRV1 or BALBRVD. Hyperimmunization of BALB/c mice with irradiated leukemias followed by in vitro sensitization of primed spleen cells resulted in the generation of CTL with high killing activity. The specificity of CTL was examined by direct cytotoxicity assays and competitive inhibition assays. A shared cell surface antigen, designated as BALBRV1 antigen, was detected by BALB/c anti-BALBRV1 CTL. BALBRV1 antigen was expressed not only on RadLV-induced BALB/c leukemias except for BALBRVD, but also on spontaneous or X-ray-induced BALB/c leukemias, chemically-induced leukemias with the H-2d haplotype and some chemically-induced BALB/c sarcomas. In contrast, a unique cell surface antigen, designated as BALBRVD antigen, was detected by BALB/c anti-BALBRVD CTL. BALBRVD antigen was expressed only on BALBRVD, but not on thirty-nine normal lymphoid or tumor cells. These two antigens could be distinguished from those previously defined on Friend, Moloney, Rauscher or Gross murine leukemia virus (MuLV) leukemias, or MuLV-related antigens. Both cytotoxic responses were blocked by antisera against H-2Kd, but not H-2Dd. The relationship of BALBRV1 antigen and BALBRVD antigen to endogenous MuLV is discussed with regard to the antigenic distribution on tumor cell lines. (author)

  12. Identification of a peptide binding protein that plays a role in antigen presentation

    The helper T-cell response to globular proteins appears, in general, to require intracellular processing of the antigen, such that a peptide fragment containing the T-cell antigenic determinant is released and transported to and held on the surface of an Ia-expressing, antigen-presenting cell. However, the molecular details underlying these phenomena are largely unknown. The means by which antigenic peptides are anchored on the antigen-presenting cell surface was investigated. A cell surface protein is identified that was isolated by it ability to bind to a 24-amino acid peptide fragment of pigeon cytochrome c, residues 81-104, containing the major antigenic determinant for B10.A mouse T cells. This peptide binding protein, purified from [35S]methionine-labeled cells, appears as two discrete bands of ≅72 and 74 kDa after NaDodSO4/PAGE. The protein can be eluted from the peptide affinity column with equivalent concentrations of either the antigenic pigeon cytochrome c peptide or the corresponding nonantigenic peptide of mouse cytochrome c. However, it does not bind to the native cytochromes c, either of pigeon or mouse, and thus the protein appears to recognize some structure available only in the free peptides. This protein plays a role in antigen presentation. Its expression is not major histocompatibility complex-restricted in that the blocking activity of the antisera can be absorbed on spleen cells from mice of different haplotypes. This peptide binding protein can be isolated from a variety of cell types, including B cells, T cells, and fibroblasts. The anchoring of processed peptides on the cell surface by such a protein may play a role in antigen presentation

  13. CD8+ T cell priming by dendritic cell vaccines requires antigen transfer to endogenous antigen presenting cells.

    Alice W Yewdall

    Full Text Available Immunotherapeutic strategies to stimulate anti-tumor immunity are promising approaches for cancer treatment. A major barrier to their success is the immunosuppressive microenvironment of tumors, which inhibits the functions of endogenous dendritic cells (DCs that are necessary for the generation of anti-tumor CD8+ T cells. To overcome this problem, autologous DCs are generated ex vivo, loaded with tumor antigens, and activated in this non-suppressive environment before administration to patients. However, DC-based vaccines rarely induce tumor regression.We examined the fate and function of these DCs following their injection using murine models, in order to better understand their interaction with the host immune system. Contrary to previous assumptions, we show that DC vaccines have an insignificant role in directly priming CD8+ T cells, but instead function primarily as vehicles for transferring antigens to endogenous antigen presenting cells, which are responsible for the subsequent activation of T cells.This reliance on endogenous immune cells may explain the limited success of current DC vaccines to treat cancer and offers new insight into how these therapies can be improved. Future approaches should focus on creating DC vaccines that are more effective at directly priming T cells, or abrogating the tumor induced suppression of endogenous DCs.

  14. Proliferating cell nuclear antigen in neutrophil fate.

    Witko-Sarsat, Véronique; Ohayon, Delphine

    2016-09-01

    The life span of a neutrophil is a tightly regulated process as extended survival is beneficial for pathogen elimination and cell death necessary to prevent cytotoxic content release from activated neutrophils at the inflammatory site. Therefore, the control between survival and death must be a dynamic process. We have previously described that proliferating cell nuclear antigen (PCNA) which is known as a nuclear protein pivotal in DNA synthesis, is a key element in controlling neutrophil survival through its association with procaspases. Contrary to the dogma which asserted that PCNA has a strictly nuclear function, in mature neutrophils, PCNA is present exclusively within the cytosol due to its nuclear export at the end of the granulocytic differentiation. More recent studies are consistent with the notion that the cytosolic scaffold of PCNA is aimed at modulating neutrophil fate rather than simply preventing death. Ultimately, targeting neutrophil survival might have important applications not just in the field of immunology and inflammation, but also in hematology and transfusion. The neutrophil emerges as a unique and powerful cellular model to unravel the basic mechanisms governing the cell cycle-independent functions of PCNA and should be considered as a leader of the pack. PMID:27558345

  15. Mapping Epitopes on a Protein Antigen by the Proteolysis of Antigen-Antibody Complexes

    Jemmerson, Ronald; Paterson, Yvonne

    1986-05-01

    A monoclonal antibody bound to a protein antigen decreases the rate of proteolytic cleavage of the antigen, having the greatest effect on those regions involved in antibody contact. Thus, an epitope can be identified by the ability of the antibody to protect one region of the antigen more than others from proteolysis. By means of this approach, two distinct epitopes, both conformationally well-ordered, were characterized on horse cytochrome c.

  16. MYELIN ANTIGEN LOAD INFLUENCES ANTIGEN PRESENTATION AND SEVERITY OF CENTRAL NERVOUS SYSTEM AUTOIMMUNITY

    Jaini, Ritika; Popescu, Daniela C.; Flask, Chris A.; Macklin, Wendy B.; Tuohy, Vincent K.

    2013-01-01

    This study was designed to understand the impact of self-antigen load on manifestation of organ specific autoimmunity. Using a transgenic mouse model characterized by CNS hypermyelination, we show that larger myelin content results in greater severity of experimental autoimmune encephalomyelitis attributable to an increased number of microglia within the hypermyelinated brain. We conclude that a larger self-antigen load affects an increase in number of tissue resident antigen presenting cells...

  17. Design, automated synthesis and immunological evaluation of NOD2-ligand–antigen conjugates

    Marian M. J. H. P. Willems

    2014-06-01

    Full Text Available The covalent attachment of an innate immune system stimulating agent to an antigen can provide active vaccine modalities capable of eliciting a potent immune response against the incorporated antigen. Here we describe the design, automated synthesis and immunological evaluation of a set of four muramyl dipeptide–peptide antigen conjugates. Muramyl dipeptide (MDP represents a well-known ligand for the intracellular NOD2 receptor and our study shows that covalently linking an MDP-moiety to an antigenic peptide can lead to a construct that is capable of stimulating the NOD2 receptor if the ligand is attached at the anomeric center of the muramic acid. The constructs can be processed by dendritic cells (DCs and the conjugation does not adversely affect the presentation of the incorporated SIINFEKL epitope on MHC-I molecules. However, stimulation of the NOD2 receptor in DCs was not sufficient to provide a strong immunostimulatory signal.

  18. The potential for induction of autoimmune disease by a randomly-mutated self-antigen

    Pedersen, Anders Elm

    2007-01-01

    The pathology of most autoimmune diseases is well described. However, the exact event that triggers the onset of the inflammatory cascade leading to disease is less certain and most autoimmune diseases are complex idiopathic diseases with no single gene known to be causative. In many cases, a...... relation to an infectious disease is described, and it is thought that microbes can play a direct role in induction of autoimmunity, for instance by molecular mimicry or bystander activation of autoreactive T cells. In contrast, less attention has been given to the possibility that modified self......-antigens can be immunogenic and lead to autoimmunity against wildtype self-antigens. In theory, modified self-antigens can arise by random errors and mutations during protein synthesis and would be recognized as foreign antigens by naïve B and T lymphocytes. Here, it is postulated that the initial auto...

  19. Tales of Antigen Evasion from CAR Therapy.

    Sadelain, Michel

    2016-06-01

    Both T cells bearing chimeric antigen receptors and tumor-specific antibodies can successfully target some malignancies, but antigen escape can lead to relapse. Two articles in this issue of Cancer Immunology Research explore what effective countermeasures may prevent it. Cancer Immunol Res; 4(6); 473-473. ©2016 AACRSee articles by Zah et al., p. 498, and Rufener et al., p. 509. PMID:27252092

  20. Antigen detection for human immunodeficiency virus.

    Harry, D J; Jennings, M B; Yee, J.; Carlson, J. R.

    1989-01-01

    The recent development of enzyme immunoassay procedures for the direct determination of human immunodeficiency virus (HIV) antigens has been of significant benefit in both clinical and research applications. The historical development of HIV antigen assays as well as their current and future applications for use in the clinical microbiology laboratory are reviewed. A detailed description of selected commercially available assays is presented, and a comparison is made of various parameters, in...

  1. Characterization of an antigenically distinct porcine rotavirus.

    Bridger, J C; Clarke, I. N.; McCrae, M A

    1982-01-01

    A porcine virus with rotavirus morphology, which was antigenically unrelated to previously described rotaviruses, is described. Particles with an outer capsid layer measured 75 nm and those lacking the outer layer were 63 nm in diameter. Particles which resembled cores were also identified. The virus was shown to be antigenically distinct from other rotaviruses as judged by immunofluorescence and immune electron microscopy, and it failed to protect piglets from challenge with porcine rotaviru...

  2. Antigenic variation in vector-borne pathogens.

    Barbour, A. G.; Restrepo, B I

    2000-01-01

    Several pathogens of humans and domestic animals depend on hematophagous arthropods to transmit them from one vertebrate reservoir host to another and maintain them in an environment. These pathogens use antigenic variation to prolong their circulation in the blood and thus increase the likelihood of transmission. By convergent evolution, bacterial and protozoal vector-borne pathogens have acquired similar genetic mechanisms for successful antigenic variation. Borrelia spp. and Anaplasma marg...

  3. Features of glycoproteins distribution in the pancreatic structures of newborn rats after prenatal antigenic influence

    Grinivetska N.V.

    2014-03-01

    Full Text Available Background. Abnormalities of digestion and absorption are the most common syndromes associated with the digestive system diseases in children. Pancreatic enzyme failure leads to violation of different metabolic processes, especially in neonates. Exocrine pancreas is sensitive to a variety of factors, including virus. It emphasizes the importance of investigation of pancreatic secretory activity in children who was born from mothers exposed to viral infection during pregnancy. Objective. The purpose is to determine the features of glycoproteins distribution in the pancreatic structures of newborn rats after prenatal antigenic influence. Methods. Animals were divided into four groups: the 1st – intact, the 2nd – intrafetal injection of the antigen, the 3rd – animals administered with antigen into the amniotic fluid, and the 4th group – control (intrafetal injection of a normal salt solution. As antigen we used Vaxigrip vaccine. Results. It was revealed that on the14th day after birth antigen-exposed animals were characterized by the increase of glycoproteins (++ in a connective tissue capsule of pancreas and decreased content of glycoproteins in the cytoplasm of acinar cells and ducts comparing with the intact group (++/+. Taken together this data evidence the reduction of the synthetic activity of acinar cells after intrafetal administration of the antigen. This may cause a predisposition for the development of dyspepsia and food allergy. Further work is planned to investigate the dynamics of glycosaminoglycans redistribution in different parts of pancreas after prenatal antigenic administrations. Citation: Grinivetska NV. [Features of glycoproteins distribution in the pancreatic structures of newborn rats after prenatal antigenic influence]. Morphologia. 2014;8(1:30-4. Ukrainian.

  4. Presentation of antigen by B cells subsets. Pt. 1. Lyb-5+ and Lyb-5- B cells differ in ability to stimulate specific T cells

    We have examined the antigen presenting cell (APC) function of different B cells. Resident, peritoneal B cells from normal mice were more efficient than splenic B cells in presenting antigen to CD4+ T cell lines. Peritoneal B cells from X-linked immunodeficient (Xid) mice, by contrast, stimulated no detectable responses. Xid splenic B cells were much less efficient APC than normal splenic B cells. B cells from neonatal mice also were very poor APC until the mice were 3 to 4 weeks old. Xid B cells presented antigen to T cell hybridomas as well as normal B cells showing that they process antigen normally. Thus, the defect is most likely in providing secondary signals. The ability of B cells to present antigen efficiency correlates with the percentage of B cells reported to express the Lyb-5 antigen. Anti-Lyb-5 serum and complement abrogated the APC activity of B cells suggesting that Lyb-5+, but not Lyb-5- cells are efficient APC. We also found that activated and resting normal splenic B cells, separated by buoyant density, presented antigen equally. Both populations also contained Lyb-5+ B cells although they were a larger fraction of the activated cells. Lyb-5 is now thought to be an activation antigen rather than a differentiation antigen. If this idea is correct, then our data indicate that anti-Lyb-5 more cleanly separates activated and resting B cells than buoyant density techniques. (author). 38 refs, 7 figs, 1 tab

  5. Transplant immuno-diagnostics: crossmatch and antigen detection.

    South, Andrew M; Grimm, Paul C

    2016-06-01

    Identifying and monitoring donor-directed anti-human leukocyte antigen antibodies are a rapidly evolving area of solid organ transplantation. Donor-specific antibodies dictate pre-transplant donor choice and donor-recipient matching and underlie much acute and chronic allograft rejection and loss. The evolution of available technology has driven this progress. Early, labor-intensive, whole-cell assays based on complement-dependent cytotoxicity suffered from poor sensitivity and specificity, technical challenges and lack of precision. Sequential improvement in assay performance included anti-human immunoglobulin-enhanced, complement-dependent cytotoxicity techniques followed by cell-based flow cytometry. However, variable specificity and sensitivity inherent in cell-based testing continued to limit flow cytometry. The introduction of solid-phase assays led to a second revolution in histocompatibility testing with the use of purified antigens bound to artificial surfaces rather than whole cells. These techniques augmented sensitivity and specificity to detect even low-titer antibodies to previously undetected antigens. Identification of complement-activating antibodies is being introduced, but current technology is in the developmental stage. While the detection of alloantibodies has improved dramatically, our comprehension of their importance remains imperfect. Variability in methodology and a lack of standardization limits the clinical application of these tests. In spite of the hurdles that remain, antibody-mediated rejection has become a key target to improve graft survival. PMID:26139577

  6. Reverse immunoediting: When immunity is edited by antigen.

    Merlo, Anna; Santa, Silvia Dalla; Dolcetti, Riccardo; Zanovello, Paola; Rosato, Antonio

    2016-07-01

    Immune selective pressure occurring during cancer immunoediting shapes tumor features revealed at clinical presentation. However, in the "Escape" phase, the tumor itself has the chance to influence the immunological response. Therefore, the capacity of the immune response to sculpt the tumor characteristics is only one side of the coin and even the opposite is likely true, i.e. that an antigen can shape the immune response in a sort of "reverse immunoediting". This reciprocal modeling probably occurs continuously, whenever the immune system encounters a tumor/foreign antigen, and can be operative in the pathogen/immune system interplay, thus possibly permeating the protective immunity as a whole. In line with this view, the characterization of a T cell response as well as the design of both active and passive immunotherapy strategies should also take into account all Ag features (type, load and presentation). Overall, we suggest that the "reverse immunoediting" hypothesis could help to dissect the complex interplay between antigens and the immune repertoire, and to improve the outcome of immunotherapeutic approaches, where T cell responses are manipulated and reprogrammed. PMID:27131431

  7. Tandem CAR T cells targeting HER2 and IL13Rα2 mitigate tumor antigen escape.

    Hegde, Meenakshi; Mukherjee, Malini; Grada, Zakaria; Pignata, Antonella; Landi, Daniel; Navai, Shoba A; Wakefield, Amanda; Fousek, Kristen; Bielamowicz, Kevin; Chow, Kevin K H; Brawley, Vita S; Byrd, Tiara T; Krebs, Simone; Gottschalk, Stephen; Wels, Winfried S; Baker, Matthew L; Dotti, Gianpietro; Mamonkin, Maksim; Brenner, Malcolm K; Orange, Jordan S; Ahmed, Nabil

    2016-08-01

    In preclinical models of glioblastoma, antigen escape variants can lead to tumor recurrence after treatment with CAR T cells that are redirected to single tumor antigens. Given the heterogeneous expression of antigens on glioblastomas, we hypothesized that a bispecific CAR molecule would mitigate antigen escape and improve the antitumor activity of T cells. Here, we created a CAR that joins a HER2-binding scFv and an IL13Rα2-binding IL-13 mutein to make a tandem CAR exodomain (TanCAR) and a CD28.ζ endodomain. We determined that patient TanCAR T cells showed distinct binding to HER2 or IL13Rα2 and had the capability to lyse autologous glioblastoma. TanCAR T cells exhibited activation dynamics that were comparable to those of single CAR T cells upon encounter of HER2 or IL13Rα2. We observed that TanCARs engaged HER2 and IL13Rα2 simultaneously by inducing HER2-IL13Rα2 heterodimers, which promoted superadditive T cell activation when both antigens were encountered concurrently. TanCAR T cell activity was more sustained but not more exhaustible than that of T cells that coexpressed a HER2 CAR and an IL13Rα2 CAR, T cells with a unispecific CAR, or a pooled product. In a murine glioblastoma model, TanCAR T cells mitigated antigen escape, displayed enhanced antitumor efficacy, and improved animal survival. Thus, TanCAR T cells show therapeutic potential to improve glioblastoma control by coengaging HER2 and IL13Rα2 in an augmented, bivalent immune synapse that enhances T cell functionality and reduces antigen escape. PMID:27427982

  8. 肺癌相关抗原RNA转染树突状细胞诱导细胞因子诱导的杀伤细胞杀伤活力的体外研究%Study of lung cancer associa ted antigen RNA-transfected DC-induced cell killing activity of CIK in vitro

    刘伯轩; 戴北鸿; 向启德; 廖东承; 高细强; 吴玉兰; 周频

    2015-01-01

    Objective To investigate the NCI-H1975 human lung adenocarcinoma cell line associated antigen RNA-transfected human dendritic cells(DCs) in vitro cytokine-induced killer(CIK) activity induced killer cells to cancer cells. Methods Using blood cell apheresis machine collecting peripheral blood mononuclear cells (PBMCs) and using mononuclear cells by density gradient centrifugation purified, cell culture flasks adherent mononuclear cells, adding recombinant human granulocyte-macrophage colony-stimulating factor(rhGM-CSF) and recombinant human interleukin -4 (rhIL-4) to induce immature DCs, extraction of total RNA NCI-H1975 cells were transfected DCs induced to mature DCs. After transfection induce mature DCs and PBMCs cultured CIK cells induced mixed culture , mixed culture with target cells again to observe the destruction of vitality. The experimental points associated antigen RNA-transfected DC-CIK group of lung cancer, non-transfected DC-CIK group and transfected with empty liposomes DC-CIK group were detected by flow cytometry analysis DC and CIK cell surface antigen expression , using CSFE/PI double staining was used to detect differences in anti-tumor activity of the three groups. Results RNA-associated antigen transfected group, DC untransfected group and transfected with empty liposome group and CIK cell surface antigen expression was significantly associated antigen RNA transfection on the group turned in primary cell killing activity and the other two groups significantly increased lung cancer. Conclusion Lung cancer associated antigen RNA-transfected DC induced killer cells to target the vitality of CIK cells was significantly enhanced for the clinical application of individual DC-CIK cells had adoptive immunotherapy offers a new approach.%目的:研究NCI-H1975人肺腺癌细胞株相关抗原RNA转染的人树突状细胞(DCs)在体外诱导细胞因子诱导的杀伤细胞(CIK)对人肺腺癌细胞的杀伤活力。方法使用血细胞单

  9. Bystander T cells in human immune responses to dengue antigens

    Suwannasaen Duangchan

    2010-09-01

    Full Text Available Abstract Background Previous studies of T cell activation in dengue infection have focused on restriction of specific T cell receptors (TCRs and classical MHC molecules. However, bystander T cell activation, which is TCR independent, occurs via cytokines in other viral infections, both in vitro and in vivo, and enables T cells to bypass certain control checkpoints. Moreover, clinical and pathological evidence has pointed to cytokines as the mediators of dengue disease severity. Therefore, we investigated bystander T cell induction by dengue viral antigen. Results Whole blood samples from 55 Thai schoolchildren aged 13-14 years were assayed for in vitro interferon-gamma (IFN-γ induction in response to inactivated dengue serotype 2 antigen (Den2. The contribution of TCR-dependent and independent pathways was tested by treatment with cyclosporin A (CsA, which inhibits TCR-dependent activation of T cells. ELISA results revealed that approximately 72% of IFN-γ production occurred via the TCR-dependent pathway. The major IFN-γ sources were natural killer (NK (mean ± SE = 55.2 ± 3.3, CD4+T (24.5 ± 3.3 and CD8+T cells (17.9 ± 1.5, respectively, as demonstrated by four-color flow cytometry. Interestingly, in addition to these cells, we found CsA-resistant IFN-γ producing T cells (CD4+T = 26.9 ± 3.6% and CD8+T = 20.3 ± 2.1% implying the existence of activated bystander T cells in response to dengue antigen in vitro. These bystander CD4+ and CD8+T cells had similar kinetics to NK cells, appeared after 12 h and were inhibited by anti-IL-12 neutralization indicating cytokine involvement. Conclusions This study described immune cell profiles and highlighted bystander T cell activation in response to dengue viral antigens of healthy people in an endemic area. Further studies on bystander T cell activation in dengue viral infection may reveal the immune mechanisms that protect or enhance pathogenesis of secondary dengue infection.

  10. Antigenic scheme for Citrobacter koseri (syn. C. diversus, Levinea malonatica); three new antigens recognized in strains from Israel.

    Gross, R. J.; Rowe, B; Sechter, I; Cahan, D.; Altman, G.

    1981-01-01

    An antigenic scheme for Citrobacter koseri was described previously and consisted of 14 'O' antigens. Three additional antigens are now added to the scheme and type strains for these antigens are designated. Their origins and their biochemical and serological reactions are described.

  11. Screening and characterization of early diagnostic antigens in excretory-secretory proteins from Trichinella spiralis intestinal infective larvae by immunoproteomics.

    Liu, Ruo Dan; Jiang, Peng; Wen, Hui; Duan, Jiang Yang; Wang, Li Ang; Li, Jie Feng; Liu, Chun Ying; Sun, Ge Ge; Wang, Zhong Quan; Cui, Jing

    2016-02-01

    The excretory-secretory (ES) antigens from Trichinella spiralis muscle larvae are the most commonly used diagnostic antigens for trichinellosis, but specific IgG antibodies were not detected in early stage of infection. The aim of this study was to identify early diagnostic antigens from ES proteins of intestinal infective larvae (IIL), the first invasive stage of T. spiralis. Six bands (92, 52, 45, 35, 32, and 29 kDa) of IIL ES proteins were recognized by infection sera in Western blotting as early as 10 days post infection. Total of 54 T. spiralis proteins in six bands were identified by shotgun LC-MS/MS, 30 proteins were annotated, and 27 had hydrolase activity. Several proteins (serine protease, putative trypsin, deoxyribonuclease II family protein, etc.) could be considered as the potential early diagnostic antigens for trichinellosis. Our study provides new insights for screening early diagnostic antigens from intestinal worms of T. spiralis. PMID:26468148

  12. MHC-restricted antigen presentation and recognition: constraints on gene, recombinant and peptide vaccines in humans

    Cunha-Neto E.

    1999-01-01

    Full Text Available The target of any immunization is to activate and expand lymphocyte clones with the desired recognition specificity and the necessary effector functions. In gene, recombinant and peptide vaccines, the immunogen is a single protein or a small assembly of epitopes from antigenic proteins. Since most immune responses against protein and peptide antigens are T-cell dependent, the molecular target of such vaccines is to generate at least 50-100 complexes between MHC molecule and the antigenic peptide per antigen-presenting cell, sensitizing a T cell population of appropriate clonal size and effector characteristics. Thus, the immunobiology of antigen recognition by T cells must be taken into account when designing new generation peptide- or gene-based vaccines. Since T cell recognition is MHC-restricted, and given the wide polymorphism of the different MHC molecules, distinct epitopes may be recognized by different individuals in the population. Therefore, the issue of whether immunization will be effective in inducing a protective immune response, covering the entire target population, becomes an important question. Many pathogens have evolved molecular mechanisms to escape recognition by the immune system by variation of antigenic protein sequences. In this short review, we will discuss the several concepts related to selection of amino acid sequences to be included in DNA and peptide vaccines.

  13. Exposed and concealed antigens as vaccine targets for controlling ticks and tick-borne diseases.

    Nuttall, P A; Trimnell, A R; Kazimirova, M; Labuda, M

    2006-04-01

    Tick vaccines derived from Bm86, a midgut membrane-bound protein of the cattle tick, Boophilus microplus, are currently the only commercially available ectoparasite vaccines. Despite its introduction to the market in 1994, and the recognized need for alternatives to chemical pesticides, progress in developing effective antitick vaccines (and ectoparasite vaccines in general) is slow. The primary rate-limiting step is the identification of suitable antigenic targets for vaccine development. Two sources of candidate vaccine antigens have been identified: 'exposed' antigens that are secreted in tick saliva during attachment and feeding on a host and 'concealed' antigens that are normally hidden from the host. Recently, a third group of antigens has been distinguished that combines the properties of both exposed and concealed antigens. This latter group offers the prospect of a broad-spectrum vaccine effective against both adults and immature stages of a wide variety of tick species. It also shows transmission-blocking and protective activity against a tick-borne pathogen. With the proliferation of molecular techniques and their application to vaccine development, there are high hopes for new and effective antitick vaccines that also control tick-borne diseases. PMID:16542317

  14. Added value of antigen ELISA in the diagnosis of neurocysticercosis in resource poor settings.

    Sarah Gabriël

    Full Text Available BACKGROUND: Neurocysticercosis (NCC is the most common cause of acquired epilepsy in Taenia solium endemic areas, primarily situated in low-income countries. Diagnosis is largely based upon the "Del Brutto diagnostic criteria" using the definitive/probable/no NCC diagnosis approach. Neuroimaging and specific T. solium cysticercosis antibody detection results are at the mainstay of this diagnosis, while antigen detection in serum has never been included. This study aimed at evaluating the addition of antigen detection as a major diagnostic criterion, especially in areas where neuroimaging is absent. METHODS: The B158/B60 monoclonal antibody-based enzyme-linked immunosorbent assay (ELISA for the detection of circulating cysticercus antigen was carried out retrospectively on serum samples collected during a hospital-based study from 83 people with epilepsy (PWE in an endemic area. RESULTS: The addition of antigen results as a major criterion allowed the correct diagnosis of definitive NCC in 10 out of 17 patients as opposed to 0/17 without antigen results in the absence of neuroimaging. A sensitivity of 100% and a specificity of 84% were determined for the diagnosis of active NCC using antigen ELISA. While the use of a higher cutoff improves the specificity of the test to 96%, it decreases its sensitivity to 83%. CONCLUSIONS: In areas where neuroimaging is absent, NCC diagnosis according to the existing criteria is problematic. Taking into account its limitations for diagnosis of inactive NCC, antigen detection can be of added value for diagnosing NCC in PWE by supporting diagnostic and treatment decisions. Therefore, we recommend a revision of the "Del Brutto diagnostic criteria" for use in resource poor areas and suggest the inclusion of serum antigen detection as a major criterion.

  15. Liposome-Based Adjuvants for Subunit Vaccines: Formulation Strategies for Subunit Antigens and Immunostimulators

    Signe Tandrup Schmidt

    2016-03-01

    Full Text Available The development of subunit vaccines has become very attractive in recent years due to their superior safety profiles as compared to traditional vaccines based on live attenuated or whole inactivated pathogens, and there is an unmet medical need for improved vaccines and vaccines against pathogens for which no effective vaccines exist. The subunit vaccine technology exploits pathogen subunits as antigens, e.g., recombinant proteins or synthetic peptides, allowing for highly specific immune responses against the pathogens. However, such antigens are usually not sufficiently immunogenic to induce protective immunity, and they are often combined with adjuvants to ensure robust immune responses. Adjuvants are capable of enhancing and/or modulating immune responses by exposing antigens to antigen-presenting cells (APCs concomitantly with conferring immune activation signals. Few adjuvant systems have been licensed for use in human vaccines, and they mainly stimulate humoral immunity. Thus, there is an unmet demand for the development of safe and efficient adjuvant systems that can also stimulate cell-mediated immunity (CMI. Adjuvants constitute a heterogeneous group of compounds, which can broadly be classified into delivery systems or immunostimulators. Liposomes are versatile delivery systems for antigens, and they can carefully be customized towards desired immune profiles by combining them with immunostimulators and optimizing their composition, physicochemical properties and antigen-loading mode. Immunostimulators represent highly diverse classes of molecules, e.g., lipids, nucleic acids, proteins and peptides, and they are ligands for pattern-recognition receptors (PRRs, which are differentially expressed on APC subsets. Different formulation strategies might thus be required for incorporation of immunostimulators and antigens, respectively, into liposomes, and the choice of immunostimulator should ideally be based on knowledge regarding the

  16. Clearance of depot vaccine SPIO-labeled antigen and substrate visualized using MRI.

    Brewer, Kimberly D; Lake, Kerry; Pelot, Nicole; Stanford, Marianne M; DeBay, Drew R; Penwell, Andrea; Weir, Genevieve M; Karkada, Mohan; Mansour, Marc; Bowen, Chris V

    2014-12-01

    Immunotherapies, including peptide-based vaccines, are a growing area of cancer research, and understanding their mechanism of action is crucial for their continued development and clinical application. Exploring the biodistribution of vaccine components may be key to understanding this action. This work used magnetic resonance imaging (MRI) to characterize the in vivo biodistribution of the antigen and oil substrate of the vaccine delivery system known as DepoVax(TM). DepoVax uses a novel adjuvanted lipid-in-oil based formulation to solubilise antigens and promote a depot effect. In this study, antigen or oil were tagged with superparamagnetic iron oxide (SPIO), making them visible on MR images. This enables tracking of individual vaccine components to determine changes in biodistribution. Mice were injected with SPIO-labeled antigen or SPIO-labeled oil, and imaged to examine clearance of labeled components from the vaccine site. The SPIO-antigen was steadily cleared, with nearly half cleared within two months post-vaccination. In contrast, the SPIO-oil remained relatively unchanged. The biodistribution of the SPIO-antigen component within the vaccine site was heterogeneous, indicating the presence of active clearance mechanisms, rather than passive diffusion or drainage. Mice injected with SPIO-antigen also showed MRI contrast for several weeks post-vaccination in the draining inguinal lymph node. These results indicate that MRI can visualize the in vivo longitudinal biodistribution of vaccine components. The sustained clearance is consistent with antigen up-take and trafficking by immune cells, leading to accumulation in the draining lymph node, which corresponds to the sustained immune responses and reduced tumor burden observed in vaccinated mice. PMID:25444822

  17. Differential Recognition and Hydrolysis of Host Carbohydrate Antigens by Streptococcus pneumoniae Family 98 Glycoside Hydrolases

    Higgins, M.; Whitworth, G; El Warry, N; Randriantsoa, M; Samain, E; Burke, R; Vocadlo, D; Boraston, A

    2009-01-01

    The presence of a fucose utilization operon in the Streptococcus pneumoniae genome and its established importance in virulence indicates a reliance of this bacterium on the harvesting of host fucose-containing glycans. The identities of these glycans, however, and how they are harvested is presently unknown. The biochemical and high resolution x-ray crystallographic analysis of two family 98 glycoside hydrolases (GH98s) from distinctive forms of the fucose utilization operon that originate from different S. pneumoniae strains reveal that one enzyme, the predominant type among pneumococcal isolates, has a unique endo-{beta}-galactosidase activity on the LewisY antigen. Altered active site topography in the other species of GH98 enzyme tune its endo-{beta}-galactosidase activity to the blood group A and B antigens. Despite their different specificities, these enzymes, and by extension all family 98 glycoside hydrolases, use an inverting catalytic mechanism. Many bacterial and viral pathogens exploit host carbohydrate antigens for adherence as a precursor to colonization or infection. However, this is the first evidence of bacterial endoglycosidase enzymes that are known to play a role in virulence and are specific for distinct host carbohydrate antigens. The strain-specific distribution of two distinct types of GH98 enzymes further suggests that S. pneumoniae strains may specialize to exploit host-specific antigens that vary from host to host, a factor that may feature in whether a strain is capable of colonizing a host or establishing an invasive infection.

  18. Nonprostatic sources of prostate-specific antigen.

    Diamandis, E P; Yu, H

    1997-05-01

    The name prostate-specific antigen has been given to a protein that now is known not to be prostate-specific; however, prostatic tissue does produces extremely high levels of PSA and secrets it into the seminal plasma. Seminal plasma contains about 1 million micrograms/L of PSA and is the richest source of PSA reported. The biologic fluid with the second highest PSA concentration, however, is nipple aspirate fluid from the female breast (up to about 5000 micrograms/L), and the third is milk from lactating women (up to 300 micrograms/L). Male serum PSA is usually less than 4 micrograms/L. In nonprostatic tissues, PSA exists mainly in its free molecular form, but PSA-ACT complex is also present in most of the fluids that contain PSA, such as breast secretions and amniotic fluid. The gene expression and protein production of PSA in nonprostatic tissues are under the regulation of steroid hormones via their receptors. Androgens, glucocorticoids, and progestins up-regulate the PSA gene expression, resulting in an increase of protein production. Estrogen by itself seems to have no effect on PSA regulation, but it can impair PSA production induced by androgen. It remains unknown whether PSA is enzymatically active and what is the physiologic role of PSA in nonprostatic tissues. It is speculated that PSA may be involved in the regulation of growth factors. Measuring PSA in breast cancer cytosol, breast-nipple aspirate fluid, and female serum may have potential clinical utilities, including breast cancer prognosis, breast cancer risk assessment, and evaluation of androgen excess. Further studies are needed to identify the exact function and regulation of PSA in nonprostatic tissues and to explore the clinical application of this protein. PMID:9126224

  19. Prevalence of Hepatitis B surface antigen in dental personnel

    Malathi Narasimhan; V K Hazarey; Saranya Varadarajan

    2015-01-01

    Context: Hepatitis B, a viral disease affecting the liver has high morbidity and mortality. Hepatitis B surface antigen (HBsAg) in serum is used to detect presence of active disease and chronic carrier status. The disease is transmitted predominantly through blood and saliva, hence dental professionals are considered a high risk group. Aim: To detect presence of HBsAg in serum of dental professionals. Subjects and Methods: The study was conducted in two parts viz., one in the year 1991 on 100...

  20. Antigen sampling in the fish intestine.

    Løkka, Guro; Koppang, Erling Olaf

    2016-11-01

    Antigen uptake in the gastrointestinal tract may induce tolerance, lead to an immune response and also to infection. In mammals, most pathogens gain access to the host though the gastrointestinal tract, and in fish as well, this route seems to be of significant importance. The epithelial surface faces a considerable challenge, functioning both as a barrier towards the external milieu but simultaneously being the site of absorption of nutrients and fluids. The mechanisms allowing antigen uptake over the epithelial barrier play a central role for maintaining the intestinal homeostasis and regulate appropriate immune responses. Such uptake has been widely studied in mammals, but also in fish, a number of experiments have been reported, seeking to reveal cells and mechanisms involved in antigen sampling. In this paper, we review these studies in addition to addressing our current knowledge of the intestinal barrier in fish and its anatomical construction. PMID:26872546

  1. Antigenic typing Polish isolates of canine parvovirus

    Polish strains of canine parvovirus isolated between 1982 and 1993 were examined to determine the extent to which the virus has evolved antigenically and genetically over eleven years. Two CPV isolates obtained in Warsaw in 1982 and Pulawy in 1993, were examined using monoclonal antibody typing, restriction analysis and sequencing VP-2 protein gene. Five other isolates from Warsaw and Pulawy were tested with the panel of monoclonal antibodies specific to CPV-2, CPV-2a and common for canine parvovirus, feline panleukopenia virus and milk enteritis virus. Results of the studies demonstrated that all isolates tested represented CPV-2a antigenic type. Rapid antigenic strain replacement recorded by Parrish and Senda in the U.S.A and Japan was not confirmed in Poland. (author). 30 refs, 2 tabs

  2. Harnessing Dendritic Cells for Tumor Antigen Presentation

    Nierkens, Stefan [Department of Tumor Immunology, Nijmegen Centre for Molecular Life Sciences, Radboud University Nijmegen Medical Centre, Geert Grooteplein 28, Nijmegen 6525 GA (Netherlands); Janssen, Edith M., E-mail: edith.janssen@cchmc.org [Division of Molecular Immunology, Cincinnati Children' s Hospital Research Foundation, University of Cincinnati College of Medicine, 3333 Burnet Avenue, Cincinnati, OH 45229 (United States)

    2011-04-26

    Dendritic cells (DC) are professional antigen presenting cells that are crucial for the induction of anti-tumor T cell responses. As a consequence, research has focused on the harnessing of DCs for therapeutic interventions. Although current strategies employing ex vivo-generated and tumor-antigen loaded DCs have been proven feasible, there are still many obstacles to overcome in order to improve clinical trial successes and offset the cost and complexity of customized cell therapy. This review focuses on one of these obstacles and a pivotal step for the priming of tumor-specific CD8{sup +} and CD4{sup +} T cells; the in vitro loading of DCs with tumor antigens.

  3. Idiopathic focal segmental glomerulosclerosis and HLA antigens

    M. Gerbase-DeLima

    1998-03-01

    Full Text Available The objective of the present study was to investigate a possible association between HLA class II antigens and idiopathic focal segmental glomerulosclerosis (FSGS. HLA-A, -B, -DR and -DQ antigens were determined in 19 Brazilian patients (16 white subjects and three subjects of Japanese origin with biopsy-proven FSGS. Comparison of the HLA antigen frequencies between white patients and white local controls showed a significant increase in HLA-DR4 frequency among FSGS patients (37.7 vs 17.2%, P<0.05. In addition, the three patients of Japanese extraction, not included in the statistical analysis, also presented HLA-DR4. In conclusion, our data confirm the association of FSGS with HLA-DR4 previously reported by others, thus providing further evidence for a role of genes of the HLA complex in the susceptibility to this disease

  4. Antigenic typing Polish isolates of canine parvovirus

    Mizak, B. [National Veterinary Research Institute, Pulawy (Poland); Plucienniczak, A. [Polish Academy ofd Sciences. Microbiology and Virology Center, Lodz (Poland)

    1995-12-31

    Polish strains of canine parvovirus isolated between 1982 and 1993 were examined to determine the extent to which the virus has evolved antigenically and genetically over eleven years. Two CPV isolates obtained in Warsaw in 1982 and Pulawy in 1993, were examined using monoclonal antibody typing, restriction analysis and sequencing VP-2 protein gene. Five other isolates from Warsaw and Pulawy were tested with the panel of monoclonal antibodies specific to CPV-2, CPV-2a and common for canine parvovirus, feline panleukopenia virus and milk enteritis virus. Results of the studies demonstrated that all isolates tested represented CPV-2a antigenic type. Rapid antigenic strain replacement recorded by Parrish and Senda in the U.S.A and Japan was not confirmed in Poland. (author). 30 refs, 2 tabs.

  5. Cytostructural Localization of a Tumor-Associated Antigen

    Howard, Donald R.; Batsakis, John G.

    1980-10-01

    Tumor cell membrane glycoproteins may be involved in the induction of tumor immunity or in the escape of tumors from immunologic defense mechanisms. Forty-four benign and malignant breast lesions were examined for the presence of a carbohydrate precursor antigen (T antigen) of the human blood group system MN. T antigen was demonstrated by means of an immunohistochemical technique to detect tissue binding of peanut agglutinin, a plant lectin, with affinity for T antigen. Malignant breast lesions showed a pattern of T antigen expression different from that of benign breast tissues. A possible role for T antigen in the modulation of the immune response to breast carcinoma is suggested.

  6. Immunogenic potential of latency associated antigens against Mycobacterium tuberculosis.

    Singh, Swati; Saraav, Iti; Sharma, Sadhna

    2014-02-01

    Tuberculosis remains a great health threat to the world among infectious diseases particularly with the advent of human immunodeficiency virus and emergence of drug resistant strains. In the light of the inconsistent efficacy imparted by the only currently available pre-exposure vaccine bacillus Calmette-Guerin BCG, the development of an improved TB vaccine is a very high international research priority. Vaccine candidates currently in clinical trials are also pre-exposure vaccines that aim to prevent active tuberculosis during an individual's lifetime. According to World Health Organization approximately a third of the world's population is latently infected with Mycobacterium tuberculosis. Dormancy or latency of Mycobacteria is associated with the formation of granuloma with poorly perfused interior leading to expression of genes which help them survive in this hostile environment. A group of about 50 genes belonging to the DosR regulon also known as latency antigens are expressed by Mycobacteria when they are persisting in the immuno-competent host. An understanding of the immunological effects produced by products of these latency induced genes may help in making a more potent vaccine. Incorporation of latency antigens into improved (live or subunit) vaccines may enhance the impact of these vaccines in which BCG priming can be followed by multisubunit protein boosting. These vaccines could act as post exposure vaccines for containment and prevention of latent TB activation. This heterologous boosting of BCG-primed immunity will be able to stimulate the known immune correlates of protective immunity against M. tuberculosis i.e. TH1 cells (CD4(+) and CD8(+) T cells) mediated immune responses with cytokines such as IFN-γ and TNF-α⋅ In our review we have analysed and compared the immunogenic potential of various latency-associated antigens of the DosR regulon in line with the current strategy of developing a recombinant post exposure booster vaccine. PMID

  7. Radioimmunoassay in the detection of the hepatitis Be antigen/antibody system in asymptomatic carriers of hepatitis B surface antigen

    A radioimmunoassay for hepatitis e antigen (HBeAg) and antibody to e (anti-HBe) was developed and sera of 71 asymptomatic chronic carriers of hepatitis B surface antigen (HBsAg), in 44 of whom liver biopsy was obtained, were tested. In addition, testing for Dane particle associated DNA polymerase activity was performed in all sera. HBeAg was detected in 14 subjects (19.7%) and anti-HBe in 46 (64.8%). The highest proportion of HBeAg positivity (40%) was found among carriers with histological evidence of chronic hepatitis, whereas anti-HBe was present in 80% of carriers with normal liver histology, in 58% of carriers with non-specific reactive hepatitis and in 60% of carriers with chronic liver lesions. DNA polymerase activity was present in 92.8% of sera positive for HBeAg, in 13% of sera positive for anti HBe, and in 9% of sera negative for both markers. Our results demonstrate that not all HBsAg carriers reactive to HBeAg show evidence of chronic hepatitis nor, conversely, that anti-HBe is invariably associated with the healthy carrier state of HBsAg. Finally, circulating Dane particles, as revealed by the presence of serum specific DNA polymerase activity, may also be present in anti-HBe positive sera other than those of some HBsAg carriers lacking both HBeAg and anti-HBe. (orig.)

  8. Ultraviolet radiation (UVR) induces cell-surface Ro/SSA antigen expression by human keratinocytes in vitro: a possible mechanism for the UVR induction of cutaneous lupus lesions

    Jones, S.K. (Bristol Royal Infirmary (United Kingdom))

    1992-06-01

    Antinuclear antibodies are useful markers of connective tissue disease. In this study, UVB but not UVA induced the expression of Ro/SSA antigen on keratinocyte surfaces in vitro. This expression was also found with the extractable nuclear antigens RnP and Sm, but not with single or double-stranded DNA. The expression was prevented by blocking protein synthesis, suggesting that it was an active process. The results suggest that UVB exposure may result in the expression of Ro/SSA antigen on the surfaces of basal keratinocytes in vivo. This antigen could then bind circulating antibody leading to the cutaneous lesions in neonatal and subacute cutaneous lupus erythematosus. (Author).

  9. Ultraviolet radiation (UVR) induces cell-surface Ro/SSA antigen expression by human keratinocytes in vitro: a possible mechanism for the UVR induction of cutaneous lupus lesions

    Antinuclear antibodies are useful markers of connective tissue disease. In this study, UVB but not UVA induced the expression of Ro/SSA antigen on keratinocyte surfaces in vitro. This expression was also found with the extractable nuclear antigens RnP and Sm, but not with single or double-stranded DNA. The expression was prevented by blocking protein synthesis, suggesting that it was an active process. The results suggest that UVB exposure may result in the expression of Ro/SSA antigen on the surfaces of basal keratinocytes in vivo. This antigen could then bind circulating antibody leading to the cutaneous lesions in neonatal and subacute cutaneous lupus erythematosus. (Author)

  10. Effect of anticancer therapy on Tn antigen exposure on the leucocyte membranes in patients with leukemia

    G. S. Maslak

    2014-08-01

    Full Text Available Tn-antigen (Thomsen-nouvelle antigen is tumor-associated carbohydrate antigen with only one GalNAc residue attached to serine or threonine of polypeptide chain. There is not enough data about the expression of this glycotope in hematologic processes. But the correlations between increasing Tn-antigen expression on the cell surface and tumor growth progression, invasion, and activation of cell migration are well known. Therefore, the currently important area of modern research is studying of the impact of anticancer therapy by expression of this carbohydrate antigen in the onco-proliferative process. There are two types of cytostatic therapies in clinical hospitals of Ukraine: COP-therapy (cyclophosphamide, vincristine, prednisone and FC-therapy (fludarabine, cyclophosphamide, which are the most popular due to their effectiveness and low price. The aim of our study was to investigate Tn-antigen exposure on the surface of lymphocytes, monocytes and granulocytes in polycythemia vera and subleukemic myelosis; to examine the influence of COP- and FC-therapies on Tn-antigen exponation in patients with chronic lymphocytic leukemia. The objects of the study were blood cells of patients with chronic lymphocytic leukemia (n = 25, polycythemia vera (n = 15 and subleukemic myelosis (n = 15 aged 58–66 years. Healthy hematologic volunteers (n = 15 aged 55 to 65 years were in the control group. Lymphocytes of patients with chronic lymphocytic leukemia (n = 25 were also studied after the chemotherapy treatment of patients divided into two groups: those who took COP-therapy (n = 13; and those who treated with FC-therapy (n = 12. Tn-antigen exposure on lymphocytes, monocytes and granulocytes was investigated by Beckman Сoulter EPICS flow cytometer with primary monoclonal Tn-antigen anybodies (Institute of Immunology, Moscow, Russia and secondary fluorescein isothiocyanate labeled antybodies (Millipore, USA. The number of dead cells was monitored by binding

  11. Antigenic characterisation of lyssaviruses in South Africa

    Ernest Ngoepe

    2014-02-01

    Full Text Available There are at least six Lyssavirus species that have been isolated in Africa, which include classical rabies virus, Lagos bat virus, Mokola virus, Duvenhage virus, Shimoni bat virus and Ikoma lyssavirus. In this retrospective study, an analysis of the antigenic reactivity patterns of lyssaviruses in South Africa against a panel of 15 anti-nucleoprotein monoclonal antibodies was undertaken. A total of 624 brain specimens, collected between 2005 and 2009, confirmed as containing lyssavirus antigen by direct fluorescent antibody test, were subjected to antigenic differentiation. The lyssaviruses were differentiated into two species, namely rabies virus (99.5% and Mokola virus (0.5%. Furthermore, rabies virus was further delineated into two common rabies biotypes in South Africa: canid and mongoose. Initially, it was found that the canid rabies biotype had two reactivity patterns; differential staining was observed with just one monoclonal antibody. This difference was likely to have been an artefact related to sample quality, as passage in cell culture restored staining. Mongoose rabies viruses were more heterogeneous, with seven antigenic reactivity patterns detected. Although Mokola viruses were identified in this study, prevalence and reservoir host species are yet to be established. These data demonstrate the usefulness of monoclonal antibody typing panels in lyssavirus surveillance with reference to emergence of new species or spread of rabies biotypes to new geographic zones.

  12. Antigen dynamics of follicular dendritic cells

    Heesters, B.A.

    2015-01-01

    Stromal-derived follicular dendritic cells (FDCs) are a major depot for antigen that are essential for formation of germinal centers, the site where memory and effector B cells differentiate and high-affinity antibody production takes place. Historically, FDCs have been characterized as ‘accessory’

  13. Antigen expression on recurrent meningioma cells

    Meningiomas are intracranial brain tumours that frequently recur. Recurrence rates up to 20% in 20 years for benign meningiomas, up to 80% for atypical meningiomas and up to 100% for malignant meningiomas, have been reported. The most important prognostic factors for meningioma recurrence are meningioma grade, meningioma invasiveness and radicality of neurosurgical resection. The aim of our study was to evaluate the differences in antigenic expression on the surface of meningioma cells between recurrent and non-recurrent meningiomas. 19 recurrent meningiomas and 35 non-recurrent meningiomas were compared regarding the expression of MIB-1 antigen, progesterone receptors, cathepsin B and cathepsin L, using immunohistochemistry. MIB-1 antigen expression was higher in the recurrent meningioma group (p=0.001). No difference in progesterone receptor status between recurrent and non-recurrent meningiomas was confirmed. Immunohistochemical intensity scores for cathepsin B (p= 0.007) and cathepsin L (p<0.001) were both higher in the recurrent than in the non-recurrent meningioma group. MIB-1 antigen expression is higher in recurrent compared to non-recurrent meningiomas. There is no difference in expression of progesterone receptors between recurrent and non-recurrent meningiomas. Cathepsins B and L are expressed more in recurrent meningiomas

  14. Lea blood group antigen on human platelets

    One- and two-stage radioligand assays were used to determine if human platelets possess the Lea antigen. Goat IgG anti-Lea antibody was purified by multiple adsorptions with Le(a-b-) human red blood cells, followed by affinity chromatography with synthetic Lea substance and labeling with 125I. Human IgG anti-Lea antibody was used either in a two stage radioassay with 125I-labeled mouse monoclonal IgG anti-human IgG as the second antibody or, alternatively, purified by Staph protein A chromatography, labeled with 125I, and used in a one-stage radioassay. Platelets from donors of appropriate red blood cell phenotypes were incubated with the antisera, centrifuged through phthalate esters, and assayed in a gamma scintillation counter. Dose response and saturation curve analysis demonstrate the presence of Lewis a antigen on platelets from Lea+ donors. Furthermore, platelets from an Le(a-b-) donor incubated in Le (a+b-) plasma adsorb Lea antigen in a similar manner to red blood cells. The clinical significance of these antigens in platelet transfusion remains undefined

  15. super oxide dismutase, an immuno dominant antigen in mycobacteria

    Tuberculosis is an ancient human scourge that continues to be an important public health problem worldwide. To control increasing incidence of tuberculosis and development of multidrug resistant strains, there is an immense need for development new diagnostic tests and vaccines etc. by understanding pathological mechanisms. Superoxide dismutase (SOD) is a 23kDa secreted antigen of M. tuberculosis which may play an important role in intracellular survival of pathogen. Therefore, SOD was targeted to study its importance in mycobacterial infection. To achieve this goal, mice were infected with live and killed BCG. These mice were then tested for humoral and cellular response to mycobacterial SOD. Antibody level was determined by ELISA and T-cell response as noted by 3H-thymidine incorporation method. Mycobacterial SOD was found to be highly immunogenic in mice. A high antibody response was noted in mice injected with live BCG. Similarly, a good T-cell proliferation response was noted in mice that were primed with live BCG. T-cells isolated from mice were also challenged with SOD or BCG infected J774 murine macrophages. J774 cells were found to process and present mycobacterial SOD that are only recognised by T-cells of mice previously infected with the live BCG. Interferon-gamma (IFN-gamma) activated J774 cells were found to be better antigen presenting cells than IFN-gamma + LPS or LPS-activated cells. (author)

  16. Cysteine proteases as potential antigens in antiparasitic DNA vaccines

    Jørgensen, Louise von Gersdorff; Buchmann, Kurt

    2011-01-01

    En litteraturgennemgang af muligheder for at bruge cystein proteaser som antigener i antiparasitære vacciner.......En litteraturgennemgang af muligheder for at bruge cystein proteaser som antigener i antiparasitære vacciner....

  17. [Identification of serological antigens in excretory-secretory antigens of Trichinella spiralis muscle larvae].

    Huang, Xuegui; He, Lifang; Yuan, Shishan; Liu, Hui; Wang, Xin

    2016-05-01

    Objective To isolate and identify serological antigens in the excretory-secretory antigens of Trichinella spiralis muscle larvae by the combination of co-immunoprecipitation and mass spectrometric technology. Methods The serum IgG of New Zealand rabbits infected with Trichinella spiralis was isolated by ammonium sulfate precipitation. Muscle larvaes were isolated from the infected muscle, and then purified and cultured to collect excretory-secretory antigens. Serological antigens in excretory-secretory antigens were isolated by co-immunoprecipitation and SDS-PAGE, and analyzed by Western blotting. Moreover, the protein bands in New Zealand rabbit sera infected with Trichinella spiralis were identified by mass spectrometric technology. Results Indirect ELISA showed that the titer of serum antibody of New Zealand rabbits infected with Trichinella spiralis was 1:6400. The rabbit serum IgG was effectively isolated by ammonium sulfate precipitation. A total of four clear protein bands of the excretory-secretory antigens of Trichinella spiralis were obtained by electrophoresis. Among them, three clear protein bands with relative molecular mass (Mr) being 40 kDa, 50 kDa and 83 kDa were recognized by the rabbit sera infected with Trichinella spiralis but not recognized by the normal rabbit sera. The obtained four protein molecules were confirmed as serine protease, specific serine protease of muscle larvae, 43 kDa secreted glycoprotein and 53 kDa excretory-secretory antigen. Conclusion Four proteins were obtained from the excretory-secretory antigens of Trichinella spiralis muscle larvae by combination of co-immunoprecipitation and mass spectrometric technique analysis, which provided new sources and insights for the diagnosis and vaccine candidates of Trichinellosis. PMID:27126943

  18. Antigenic profiling of Yersinia pestis infection in the Wyoming coyote (Canis latrans)

    Vernati, G.; Edwards, W.H.; Rocke, T.E.; Little, S.F.; Andrews, G.P.

    2011-01-01

    Although Yersinia pestis is classified as a "high-virulence" pathogen, some host species are variably susceptible to disease. Coyotes (Canis latrans) exhibit mild, if any, symptoms during infection, but antibody production occurs postinfection. This immune response has been reported to be against the F1 capsule, although little subsequent characterization has been conducted. To further define the nature of coyote humoral immunity to plague, qualitative serology was conducted to assess the antiplague antibody repertoire. Humoral responses to six plasmid-encoded Y. pestis virulence factors were first examined. Of 20 individual immune coyotes, 90% were reactive to at least one other antigen in the panel other than F1. The frequency of reactivity to low calcium response plasmid (pLcr)-encoded Yersinia protein kinase A (YpkA) and Yersinia outer protein D (YopD) was significantly greater than that previously observed in a murine model for plague. Additionally, both V antigen and plasminogen activator were reactive with over half of the serum samples tested. Reactivity to F1 was markedly less frequent in coyotes (35%). Twenty previously tested antibody-negative samples were also examined. While the majority were negative across the panel, 15% were positive for 1-3 non-F1 antigens. In vivo-induced antigen technology employed to identify novel chromosomal genes of Y. pestis that are up-regulated during infection resulted in the identification of five proteins, including a flagellar component (FliP) that was uniquely reactive with the coyote serum compared with immune serum from two other host species. Collectively, these data suggest that humoral immunity to pLcr-encoded antigens and the pesticin plasmid (pPst)-encoded Pla antigen may be relevant to plague resistance in coyotes. The serologic profile of Y. pestis chromosomal antigens up-regulated in vivo specific to C. latrans may provide insight into the differences in the pathogen-host responses during Y. pestis infection.

  19. Blood group antigen studies using CdTe quantum dots and flow cytometry.

    Cabral Filho, Paulo E; Pereira, Maria I A; Fernandes, Heloise P; de Thomaz, Andre A; Cesar, Carlos L; Santos, Beate S; Barjas-Castro, Maria L; Fontes, Adriana

    2015-01-01

    New methods of analysis involving semiconductor nanocrystals (quantum dots [QDs]) as fluorescent probes have been highlighted in life science. QDs present some advantages when compared to organic dyes, such as size-tunable emission spectra, broad absorption bands, and principally exceptional resistance to photobleaching. Methods applying QDs can be simple, not laborious, and can present high sensibility, allowing biomolecule identification and quantification with high specificity. In this context, the aim of this work was to apply dual-color CdTe QDs to quantify red blood cell (RBC) antigen expression on cell surface by flow cytometric analysis. QDs were conjugated to anti-A or anti-B monoclonal antibodies, as well as to the anti-H (Ulex europaeus I) lectin, to investigate RBCs of A1, B, A1B, O, A2, and Aweak donors. Bioconjugates were capable of distinguishing the different expressions of RBC antigens, both by labeling efficiency and by flow cytometry histogram profile. Furthermore, results showed that RBCs from Aweak donors present fewer amounts of A antigens and higher amounts of H, when compared to A1 RBCs. In the A group, the amount of A antigens decreased as A1 > A3 > AX = Ael, while H antigens were AX = Ael > A1. Bioconjugates presented stability and remained active for at least 6 months. In conclusion, this methodology with high sensibility and specificity can be applied to study a variety of RBC antigens, and, as a quantitative tool, can help in achieving a better comprehension of the antigen expression patterns on RBC membranes. PMID:26185442

  20. The common mycobacterial antigens and their importance in the treatment of disease.

    Stanford, John; Stanford, Cynthia; Stansby, Gerard; Bottasso, Oscar; Bahr, Georges; Grange, John

    2009-01-01

    The mycobacteria are one of a number of genera making up the aerobic Actinomycetales. Their antigens demonstrable by immuno-precipitation methods can be divided into four groups. The group i antigens, common to all mycobacterial species, cross-react with their counterparts in animal cells, largely derived from mitochondria. Notable amongst these antigens are the heat-shock, or stress, proteins and possibly bacterial sugars. Tests of cell-mediated immunity show that people can be separated by their responsiveness in skin-test, or lymphocyte proliferation techniques, into four categories of responders. Category 1 individuals respond to all mycobacterial reagents through recognition of the group i antigens. Many chronic diseases are associated with a lack of cell-mediated responsiveness to the group i antigens, and have a raised antibody titre to them. This reflects a predominance of T helper 2 activity and reduced T helper 1 responsiveness as part of the pathogenesis of their diseases, which include chronic bacterial, viral and parasitic infections, allergies, auto-immunities and neoplasms. Packaged together, the group i antigens and the cell-wall adjuvants of selected aerobic Actinomycetales make potent immuno-modulatory reagents. An example is heat-killed Mycobacterium vaccae, useful in both prevention and treatment of disease. Treatment with such reagents results in alleviation of disease, restoration of cellular responsiveness to the common mycobacterial antigens and a decrease in antibody titres to them. This new approach to treatment for such a wide range of diseases has few disadvantageous side effects and can accompany other non-immunosuppressive therapies. PMID:19355964

  1. Identification of antigenically related polypeptides at centrioles and basal bodies.

    Lin, W.; Fung, B.; Shyamala, M; Kasamatsu, H

    1981-01-01

    An antigen localized at the centriolar region has been identified by indirect immunofluorescence studies in African green monkey kidney, human, hamster, rat, and mouse cells. The antigen consists of two polypeptides of 14,000 and 17,000 daltons. A related antigen is also present at the basal body region in ciliated cells from chicken, cat, mouse, pig, steer, and rabbit trachea and from rabbit fimbria. Immunoelectron microscopy shows that the immunoreactive antigen is indeed located in the reg...

  2. A prospective study of serum tumour markers carcinoembryonic antigen, carbohydrate antigens 50 and 242, tissue polypeptide antigen and tissue polypeptide specific antigen in the diagnosis of pancreatic cancer with special reference to multivariate diagnostic score.

    Pasanen, P. A.; Eskelinen, M.; Partanen, K.; Pikkarainen, P; Penttilä, I.; Alhava, E

    1994-01-01

    The aim of this study was to assess by a stepwise multivariate discriminant analysis the value of four current serum tumour markers - carcinoembryonic antigen (CEA), carbohydrate antigen (CA) 50 and CA 242 and tissue polypeptide antigen (TPA) - and a new serum tumour marker, tissue polypeptide specific antigen (TPS), in the diagnosis of pancreatic cancer. The serum values were measured in a prospective series of patients with jaundice, with unjaundiced cholestasis and with a suspicion of chro...

  3. Single-Antigen Serological Testing for Bovine Tuberculosis▿

    Green, Lawrence R.; Jones, Cynthia C.; Sherwood, Anne L.; Garkavi, Inna V.; Cangelosi, Gerard A.; Thacker, Tyler C.; Palmer, Mitchell V.; Waters, W. Ray; Rathe, Chris V.

    2009-01-01

    Antibody responses are useful indicators of Mycobacterium bovis infection of cattle. Tests for such responses often use multiple M. bovis antigens as detection probes. This is recommended because responses to single antigens may be too variable for consistent diagnosis. However, the use of multiple antigens increases costs and the risk of false-positive results. As an alternative, the SeraLyte-Mbv system detects responses to a single M. bovis antigen, MPB83, by using a chemiluminescent testin...

  4. Pneumocystis carinii from pigs and humans are antigenically distinct

    Christensen, C B; Settnes, Osvald Peter; Bille-Hansen, Vivi; Jorsal, Sven Erik Lind; Henriksen, S A; Lundgren, B

    1996-01-01

    The antigens of Pneumocystis carinii cysts isolated from pigs and humans were compared by the Western immunoblotting technique. Convalescent pig serum reacted with two antigens (approximately 78 kDa and 32.5 kDa) of porcine P. carinii cysts, whereas convalescent serum from humans did not react with...... porcine P. carinii cyst antigens. The results indicate that porcine and human P. carinii cysts are antigenically distinct....

  5. Characterization of antigens of the dog major histocompatibility complex

    Feltz, Machteld

    1983-01-01

    textabstractIn this thesis, an immunochemical analysis of dog Major Histocompatibility Complex (MHC) antigens, also called DLA antigens, is described. MHC antigens play a prominent role in the immune system, particularly in the recognition of foreign material. They can be divided into four classes. As only DLA class I antigens have been defined by well characterized reagents (antisera), they were chosen as the object of the investigation

  6. Detection of antigens in urine during acute toxoplasmosis.

    Huskinson, J; Stepick-Biek, P; Remington, J S

    1989-01-01

    Toxoplasma antigens were detected in sera and urine of mice acutely infected with Toxoplasma gondii. The concentrations of antigens in the urine samples measured by enzyme-linked immunosorbent assay were similar to those detected in the sera of the corresponding mice. The major antigens were not dialyzable and were largely destroyed by treatment with trichloroacetic acid and heat (100 degrees C for 1 h). Toxoplasma antigens were demonstrable on Western blots (immunoblots) of the urine samples.

  7. ERAP1 functions override the intrinsic selection of specific antigens as immunodominant peptides, thereby altering the potency of antigen-specific cytolytic and effector memory T-cell responses.

    Rastall, David P W; Aldhamen, Yasser A; Seregin, Sergey S; Godbehere, Sarah; Amalfitano, Andrea

    2014-12-01

    Endoplasmic reticulum aminopeptidase 1 (ERAP1) is a critical component of the adaptive immune system that has been shown to increase or decrease the presentation of specific peptides on MHC class I molecules. Here, we have demonstrated that ERAP1 functions are not only important during the presentation of antigen-derived peptides, but these functions can also completely change which antigen-derived peptides ultimately become selected as immunodominant T-cell epitopes. Our results suggest that ERAP1 may do this by destroying epitopes that would otherwise become immunodominant in the absence of adequate ERAP1 functionality. We further establish that ERAP1-mediated influences on T-cell functions are both qualitative and quantitative, by demonstrating that loss of ERAP1 function redirects CTL killing toward a different set of antigen-derived epitopes and increases the percent of antigen-specific memory T cells elicited by antigen exposure. As a result, our studies suggest that normal ERAP1 activity can act to suppress the numbers of T effector memory cells that respond to a given antigen. This unique finding may shed light on why certain ERAP1 single nucleotide polymorphisms are associated with several autoimmune diseases, for example, by significantly altering the robustness and quality of CD8+ T-cell memory responses to antigen-derived peptides. PMID:25087231

  8. Antigen-Specific CD4 T Cells Are Induced after Intravesical BCG-Instillation Therapy in Patients with Bladder Cancer and Show Similar Cytokine Profiles as in Active Tuberculosis

    Elsäßer, Julia; Janssen, Martin W.; Becker, Frank; Suttmann, Henrik; Schmitt, Kai; Sester, Urban; Stöckle, Michael; Sester, Martina

    2013-01-01

    Specific T cell immunity in patients with active tuberculosis is associated with a decrease in multifunctionality. However, it is unknown whether cytokine profiles differ in patients with primary infection and those with prior contact. We therefore used intravesical immunotherapy with attenuated live Bacille Calmette–Guérin (BCG) in patients with urothelial carcinoma as a model to characterise the induction of systemic immunity towards purified protein derivate (PPD) and to study whether cyto...

  9. Lipid motif of a bacterial antigen mediates immune responses via TLR2 signaling.

    Amit A Lugade

    Full Text Available The cross-talk between the innate and the adaptive immune system is facilitated by the initial interaction of antigen with dendritic cells. As DCs express a large array of TLRs, evidence has accumulated that engagement of these molecules contributes to the activation of adaptive immunity. We have evaluated the immunostimulatory role of the highly-conserved outer membrane lipoprotein P6 from non-typeable Haemophilus influenzae (NTHI to determine whether the presence of the lipid motif plays a critical role on its immunogenicity. We undertook a systematic analysis of the role that the lipid motif plays in the activation of DCs and the subsequent stimulation of antigen-specific T and B cells. To facilitate our studies, recombinant P6 protein that lacked the lipid motif was generated. Mice immunized with non-lipidated rP6 were unable to elicit high titers of anti-P6 Ig. Expression of the lipid motif on P6 was also required for proliferation and cytokine secretion by antigen-specific T cells. Upregulation of T cell costimulatory molecules was abrogated in DCs exposed to non-lipidated rP6 and in TLR2(-/- DCs exposed to native P6, thereby resulting in diminished adaptive immune responses. Absence of either the lipid motif on the antigen or TLR2 expression resulted in diminished cytokine production from stimulated DCs. Collectively, our data suggest that the lipid motif of the lipoprotein antigen is essential for triggering TLR2 signaling and effective stimulation of APCs. Our studies establish the pivotal role of a bacterial lipid motif on activating both innate and adaptive immune responses to an otherwise poorly immunogenic protein antigen.

  10. The ganglioside antigen GD2 is surface-expressed in Ewing sarcoma and allows for MHC-independent immune targeting

    Kailayangiri, S; Altvater, B; Meltzer, J; Pscherer, S; Luecke, A.; Dierkes, C. (Christian); Titze, U; Leuchte, K; Landmeier, S. (Silke); Hotfilder, M; Dirksen, U; Hardes, J.; Gosheger, G.; Juergens, H; Rossig, C.

    2012-01-01

    Background: Novel treatment strategies are needed to cure disseminated Ewing sarcoma. Primitive neuroectodermal features and a mesenchymal stem cell origin are both compatible with aberrant expression of the ganglioside antigen GD2 and led us to explore GD2 immune targeting in this cancer. Methods: We investigated GD2 expression in Ewing sarcoma by immunofluorescence staining. We then assessed the antitumour activity of T cells expressing a chimeric antigen receptor specific for GD2 against E...

  11. Seoul virus suppresses NF-κB-mediated inflammatory responses of antigen presenting cells from Norway rats

    Au, Rebecca Y.; Jedlicka, Anne E.; Li, Wei; Pekosz, Andrew; Klein, Sabra L.

    2010-01-01

    Hantavirus infection reduces antiviral defenses, increases regulatory responses, and causes persistent infection in rodent hosts. To address whether hantaviruses alter the maturation and functional activity of antigen presenting cells (APCs), rat bone marrow-derived dendritic cells (BMDCs) and macrophages (BMDMs) were generated and infected with Seoul virus (SEOV) or stimulated with TLR ligands. SEOV infected both DCs and macrophages, but copies of viral RNA, viral antigen, and infectious vir...

  12. Antigens of Brucella abortus S19 immunodominant for bovine lymphocytes as identified by one- and two-dimensional cellular immunoblotting.

    Brooks-Worrell, B M; Splitter, G A

    1992-01-01

    Cellular immune responses are influential for protection against intracellular bacteria such as brucellae. Therefore, identification of Brucella abortus antigens that activate primed bovine lymphocytes is fundamental for discerning the breadth of cellular response in bovine brucellosis. Potentially antigenic components of B. abortus S19 were isolated by sodium dodecyl sulfate-polyacrylamide gel electrophoresis followed by nitrocellulose blotting. Specific one-dimensional blot segments induced...

  13. Photoaffinity labeling demonstrates binding between Ia and antigen on antigen-presenting cells

    Antigen-presenting cells (APCs) bind and present antigens to immunocompetent T lymphocytes in the context of Ia molecules: however, the molecular nature of the immunogenic complexes on the surface of these cells is unknown. They have used radioiodinated photoreactive Beef insulin (BI) derivatized in the B29 position with (n-[4-(4'-azido-3'-[125]iodophenylazo)benzoyl]-3-aminopropyl-n-oxy-succinimide) (B29-AZAP) as antigen to examine the nature of these molecular complexes. The probe was reacted with either of two B hybridoma APCs, TA3 (Ia/sup k/d/) and LB(Ia/sup d/b/) which present insulin on I-A/sup d/ and I-A/sub b/ respectively, to appropriately restricted, BI specific T helper lymphocytes (T/sub H/). Samples were photolyzed, solubilized and then analyzed by SDS-PAGE. Two protein bands of 36-kDa and 27-kDa were specifically labeled on TA3 and LB cells. Treatment of these bands with dithiothreitol or endo-N-β-glycosidase F demonstrates that each is composed of a single glycoprotein. These bands are immunoprecipitable with haplotype specific but not control anti-Ia antibodies. This identifies the labeled bands as the α- and β- subunits of class II MHC antigens. They conclude that a molecular complex may form between Ia and antigen on APCs and that formation of this complex does not require the presence of an antigen specific T/sub H/ cell receptor

  14. Targeting of tumor-associated antigens (TAA) in experimental immunotherapy

    We have previously shown the superiority of tumor-associated antigens (TAA) to function as effective immunogens when administered with bilayer membrane vesicles called liposomes. The ability of liposomes to target TAA to host antigen-presenting cells is analyzed here. 1-Butanol extracted TAA from two syngeneic rat colon cancer tumors (WB 2054 and W 1756) was radioiodinated (131I-TAA). Free 131I and 131I-TAA (2.8 X 10(7) cpm and 75 micrograms TAA per rat) were used as tracers, with or without incorporation into liposomes (composition: sphingomyelin, cholesterol, dicetyl phosphate at 70:24:6 molar ratio). Six groups of male rats (BN X WF for WB2054 and Wistar/Furth for W1756, n = 18 each group) were injected iv with either free tracers or the tracers incorporated into liposomes. Whole blood clearance curve was biphasic (half-life alpha = 5 min; half life beta = 12 hr), suggesting a two-compartmental model of distribution. Seven animals from each group were sacrificed at set times (15 min to 48 hr), organs harvested and cpm/g of tissue estimated. Liposome 131I and liposome 131I-TAA were targeted to and retained preferentially in liver and spleen. Four animals from each group were imaged serially using a gamma camera. Matched pair analysis of regions showed persistently higher activity in liver-spleen area when liposomes were used (P less than 0.001). The uptake of radiolabeled antigens by plastic adherent mononuclear cells in liver and spleen was significantly higher when presented with liposomes (macrophage uptake index: liver = 1.65 vs 0.55; spleen = 5.85 vs 1.15; with and without liposomes, respectively)

  15. Characterization of a human antigen specific helper factor

    While antigen (Ag) specific helper factors have been characterized in mice, similar molecules have not been identified in humans. To characterize human antigen specific helper molecules, an IL-2 dependent tetanus toxoid (T.T.) reactive T cell line was fused with a 6-thioguanine resistant CEM line, and hybrids selected in medium containing hypoxanthine and azaserine. Hybrids were screened by culturing the cells with 35S-Met then reacting the supernatants with T.T. or hepatitis vaccine immobilized on nitrocellulose. One hybrid, TT6BA-O, was identified which secreted a Met-containing molecule which bound T.T. but not hepatitis vaccine. Supernatants from TT6BA-O, but not the parent CEM line, when added to autologous peripheral blood mononuclear cells (PBMC's) stimulated secretion of T.T. specific antibodies (Abs). Specificity controls demonstrated that TT6BA-O supernatant did not induce antibodies to diphtheria toxoid, hepatitis vaccine or pneumococcal polysaccharide, and total immunoglobulin (lg) synthesis was minimally increased. In contrast, pokeweed mitogen stimulated significant lg synthesis as well as Ab's to pneumococcal polysaccharide and T.T. TT6BA-O supernatant induced anti-T.T.Ab's in autologous PBMC's but not PBMC's from 3 unrelated donors, suggesting that the activity of the helper factor is restricted, possibly by the MHC. The molecular weight of the helper factor was estimated at 100,000-150,000 by Sephacryl S-300 chromatography. Finally, the helper factor could be demonstrated to bind and elute from sephorose-immobilized T.T. and anti-DR antisera, but not anti-lg antisera or the T40/25 monoclonal antibody, which binds a nonpolymorphic determinant on the human T cell receptor. These results demonstrate that human Ag specific helper factors exist, bind antigen and bear class II MHC determinants

  16. 21 CFR 866.3402 - Plasmodium species antigen detection assays.

    2010-04-01

    ... 21 Food and Drugs 8 2010-04-01 2010-04-01 false Plasmodium species antigen detection assays. 866... Plasmodium species antigen detection assays. (a) Identification. A Plasmodium species antigen detection assay... malaria caused by the four malaria species capable of infecting humans: Plasmodium falciparum,...

  17. 9 CFR 113.408 - Avian mycoplasma antigen.

    2010-01-01

    ... with 9 CFR 114.8. If phenol is used, a direct titration with a standardized bromide-bromate solution... 9 Animals and Animal Products 1 2010-01-01 2010-01-01 false Avian mycoplasma antigen. 113.408... Diagnostics and Reagents § 113.408 Avian mycoplasma antigen. Mycoplasma antigens shall be prepared...

  18. Mapping epitopes and antigenicity by site-directed masking

    Paus, Didrik; Winter, Greg

    2006-06-01

    Here we describe a method for mapping the binding of antibodies to the surface of a folded antigen. We first created a panel of mutant antigens (-lactamase) in which single surface-exposed residues were mutated to cysteine. We then chemically tethered the cysteine residues to a solid phase, thereby masking a surface patch centered on each cysteine residue and blocking the binding of antibodies to this region of the surface. By these means we mapped the epitopes of several mAbs directed to -lactamase. Furthermore, by depleting samples of polyclonal antisera to the masked antigens and measuring the binding of each depleted sample of antisera to unmasked antigen, we mapped the antigenicity of 23 different epitopes. After immunization of mice and rabbits with -lactamase in Freund's adjuvant, we found that the antisera reacted with both native and denatured antigen and that the antibody response was mainly directed to an exposed and flexible loop region of the native antigen. By contrast, after immunization in PBS, we found that the antisera reacted only weakly with denatured antigen and that the antibody response was more evenly distributed over the antigenic surface. We suggest that denatured antigen (created during emulsification in Freund's adjuvant) elicits antibodies that bind mainly to the flexible regions of the native protein and that this explains the correlation between antigenicity and backbone flexibility. Denaturation of antigen during vaccination or natural infections would therefore be expected to focus the antibody response to the flexible loops. backbone flexibility | Freund's adjuvant | conformational epitope | antisera

  19. 21 CFR 660.40 - Hepatitis B Surface Antigen.

    2010-04-01

    ... 21 Food and Drugs 7 2010-04-01 2010-04-01 false Hepatitis B Surface Antigen. 660.40 Section 660.40...) BIOLOGICS ADDITIONAL STANDARDS FOR DIAGNOSTIC SUBSTANCES FOR LABORATORY TESTS Hepatitis B Surface Antigen § 660.40 Hepatitis B Surface Antigen. (a) Proper name and definition. The proper name of this...

  20. Use of magnetic nanobeads to study intracellular antigen processing

    Magnetic nanobeads were covalently linked to antigens and used as a tool to simultaneously follow their intracellular transport into the cells and specifically purify the intracellular compartments implicated in antigen processing. The protein content of these vesicles was analysed by 2D-electrophoresis. Furthermore, nanobeads allowed intracellular localisation of the antigen in electron and fluorescence microscopy

  1. Use of magnetic nanobeads to study intracellular antigen processing

    Perrin-Cocon, Laure A.; Chesne, Serge; Pignot-Paintrand, Isabelle; Marche, Patrice N.; Villiers, Christian L. E-mail: christian.villiers@cea.fr

    2001-07-01

    Magnetic nanobeads were covalently linked to antigens and used as a tool to simultaneously follow their intracellular transport into the cells and specifically purify the intracellular compartments implicated in antigen processing. The protein content of these vesicles was analysed by 2D-electrophoresis. Furthermore, nanobeads allowed intracellular localisation of the antigen in electron and fluorescence microscopy.

  2. Tolerization of an established αb-crystallin-reactive T-cell response by intravenous antigen

    Verbeek, R.; Mark, K. van der; Wawrousek, E.F.; Plomp, A.C.; Noort, J.M. van

    2007-01-01

    Tolerance induction to prevent activation of a naïve T-cell repertoire has been well documented in rodents and can be readily achieved by intravenous, oral or intranasal administration of antigen in the absence of adjuvants. In autoimmune diseases such as multiple sclerosis (MS) the presence of an e

  3. Composition of inflammatory infiltrate and its correlation with HBV/HCV antigen expression

    Bozena Walewska-Zielecka; Kazimierz Madalinski; Joanna Jablonska; Paulina Godzik; Joanna Cielecka-Kuszyk; Bogumila Litwinska

    2008-01-01

    AIM: To study the composition of liver inflammatory infiltrate in biopsy material from patients chronically infected with hepatotropic viruses and to evaluate the correlation of inflammatory infiltrate with hepatitis B virus (HBV) and hepatitis C virus (HCV) viral antigen expression in chronic B and C hepatitis.METHODS: The phenotype of inflammatory cells was evaluated by the EnVision system, using a panel of monoclonal antibodies. HBV and HCV antigens were detected with the use of monoclonal anti-HBs, poly-clonal anti-HBc and anti-HCV antibodies, respectively.RESULTS: The cellular composition of liver inflammatory infiltrate was similar in the patients with B and C hepatitis: ~50%-60% of cells were T helper lymphooltes. Approximately 25% were T cytotoxic lymphocytes; B lymphocytes comprised 15% of inflammatory infiltrate; other cells, including NK, totalled 10%. Expression of HLA antigens paralleled inflammatory activity. Portal lymphadenoplasia was found more often in hepatitis C (54.5%) than in hepatitis B (30.6%). Expression of HB-cAg was found more often in chronic B hepatitis of moderate or severe activity. Overall inflammatory activity in HBV-infected cases did not correlate with the intensity of HBsAg expression in hepatooltes. Inflammatory infiltrates accompanied the focal expression of HCV anti-gens. A direct correlation between antigen expression and inflammatory reaction in situ was noted more often in hepatitis C than B.CONCLUSION: Irrespective of the etiology and activity of hepatitis, components of the inflammatory infiltrate in liver were similar. Overall inflammatory activity did not correlate with the expression of HBsAg and HCVAg; HBcAg expression, however, accompanied chronic hepatitis B of moderate and severe activity.

  4. Monoclonal antibodies against human Ia antigens stimulate monocytes to secrete interleukin 1.

    Palacios, R

    1985-01-01

    The monoclonal antibodies (mAb) DA6.147, DA6.164, and HIG.48 against human Ia antigens, but not the W6/32 mAb against human class I major histocompatibility complex antigens or the anti-monocyte OKM1 and 63D3 mAb, stimulated monocytes to secrete interleukin 1 (IL-1). IL-1 was measured by its property of promoting the production of interleukin 2 (IL-2) by phytohemagglutinin-treated LBRM-33 clone 1A5 cells. IL-1 activity induced by anti-Ia antibodies could be detected 24 hr after initiation of ...

  5. Antigen-specific CD4 T cells are induced after intravesical BCG-instillation therapy in patients with bladder cancer and show similar cytokine profiles as in active tuberculosis.

    Elsäßer, Julia; Janssen, Martin W; Becker, Frank; Suttmann, Henrik; Schmitt, Kai; Sester, Urban; Stöckle, Michael; Sester, Martina

    2013-01-01

    Specific T cell immunity in patients with active tuberculosis is associated with a decrease in multifunctionality. However, it is unknown whether cytokine profiles differ in patients with primary infection and those with prior contact. We therefore used intravesical immunotherapy with attenuated live Bacille Calmette-Guérin (BCG) in patients with urothelial carcinoma as a model to characterise the induction of systemic immunity towards purified protein derivate (PPD) and to study whether cytokine profiles differ depending on pre-existing immunity. Eighteen patients with non-muscle invasive bladder cancer were recruited during the BCG-induction course. Fifty-four healthy individuals served as controls. Interferon (IFN)-γ and interleukin (IL)-2 producing PPD-specific CD4 T cells were analysed longitudinally before each instillation using a rapid flow-cytometric whole blood immunoassay. Baseline levels of IFN-γ producing PPD-specific T cells were comparable to controls. T cells showed a 5-fold increase to 0.23% by week 2/3, and further increased 8-fold by week 4/5 (to 0.42%, p=0.0007). Systemic immunity was induced in all patients, although the increase was less pronounced in patients with pre-existing immunity. As in active TB, cytokine profiling during therapy revealed a lower percentage of multifunctional IFN-γ/IL-2 double-positive T cells compared to controls (60.2% vs. 71.9%, p=0.0003). Of note, when comparing patients with and without pre-existing immunity, cytokine profiles in patients with primary immunity were shifted towards IL-2 single producing T cells (p=0.02), whereas those in patients with pre-existing immunity were shifted towards IFN-γ single-positivity (p=0.01). In conclusion, systemic T cell responses were induced after BCG-therapy, and their kinetics and cytokine profile depended on pre-existing immunity. Decreased functionality is a typical feature of specific immunity in both patients with active tuberculosis and BCG-therapy. Among patients

  6. Antigen uptake, processing and presentation to T-cells is still functional in dendritic cells surviving photodynamic treatment

    Full text: The effect of photodynamic therapy (PDT) on anti-tumoral immune reactions is still discussed controversially. Several studies have demonstrated that PDT is able to activate immune reactions against tumor antigens. However, there is also evidence that PDT exerts immunosuppressive effects. Dendritic cells (DC) are professional antigen presenting cells and play an important role in, both, the induction of immune reactions as well as the induction and maintenance of immunologic tolerance. Therefore, we investigated the effect of hypericin-mediated PDT on the capability of bone marrow-derived DC for antigen uptake, processing and presentation to CD4+ T lymphocytes. Using beta-galactosidase as model antigens we found that, under sublethal PDT conditions, antigen is still incorporated and degraded by surviving DC. PDT-treated DC, in the presence of beta-galactosidase, were still able to re-activate splenic T cells from immunized but not from naive mice. Similarly, naive allogenic T cells were activated in an antigen-independent manner by PDT-treated DC, albeit at lower efficiency as compared to untreated DC. Based on these data, we hypothesize that DC localized in PDT-treated tumor lesions could play a role in the regulation of anti-tumor immune reactions. (author)

  7. Evidence that a glycolipid tail anchors antigen 117 to the plasma membrane of Dictyostelium discoideum cells

    The authors describe the biochemical features of the putative cell cohesion molecule antigen 117, indicating that it is anchored to the plasma membrane by a glycolipid tail. Antigen 117 can be radiolabeled with [3H]myristate, [3H]palmitate, and [14C]ethanolamine. The fatty acid label is removed by periodate oxidation and nitrous acid deamination, indicating that the fatty acid is attached to the protein by a structure containing carbohydrate and an unsubstituted glucosamine. As cells develop aggregation competence, the antigen is released from the cell surface in a soluble form that can still be radiolabeled with [14C]ethanolamine but not with [3H]myristate of [3H]-palmitate. The molecular weight of the released antigen is similar to that found in the plasma membrane, but it preferentially partitions in Triton X-114 as a hydrophilic, as opposed to a hydrophobic, protein. Plasma membranes contain the enzyme activity responsible for the release of the antigen in a soluble form

  8. Rapid production of antigen-specific monoclonal antibodies from a variety of animals

    Kurosawa Nobuyuki

    2012-09-01

    Full Text Available Abstract Background Although a variety of animals have been used to produce polyclonal antibodies against antigens, the production of antigen-specific monoclonal antibodies from animals remains challenging. Results We propose a simple and rapid strategy to produce monoclonal antibodies from a variety of animals. By staining lymph node cells with an antibody against immunoglobulin and a fluorescent dye specific for the endoplasmic reticulum, plasma/plasmablast cells were identified without using a series of antibodies against lineage markers. By using a fluorescently labeled antigen as a tag for a complementary cell surface immunoglobulin, antigen-specific plasma/plasmablast cells were sorted from the rest of the cell population by fluorescence-activated cell sorting. Amplification of cognate pairs of immunoglobulin heavy and light chain genes followed by DNA transfection into 293FT cells resulted in the highly efficient production of antigen-specific monoclonal antibodies from a variety of immunized animals. Conclusions Our technology eliminates the need for both cell propagation and screening processes, offering a significant advantage over hybridoma and display strategies.

  9. Dynamics of antigen delivery and the functional roles of L121-adjuvant.

    Shen, Shan-Shan; Yang, Ya-Wun

    2015-08-20

    This study investigates the intracellular transport of protein antigens facilitated by L121-adjuvants and examines the associated cytotoxic T lymphocyte (CTL) effect. EL4 mouse thymoma cells were treated with L121-adjuvant and stained with AnnexinV-propidium iodide (PI) followed by flow cytometric analysis. The intracellular trafficking dynamics of bovine serum albumin (BSA)-FITC in the J774.A.1 macrophages, influenced by the L121-adjuvant, was visualized by confocal microscopy. The antigen-specific cytotoxic T lymphocyte (CTL) effect induced by the L121-adjuvant was determined by the cleavage-specific fluorogenic caspase substrate. The trafficking of BSA-FITC in the J774A.1 cells by confocal microscopy illustrated that the L121-adjuvant facilitated the intracellular transport of proteins to the subcellular compartments, including the lysosome, endoplasmic reticulum (ER), and the cis-Golgi apparatus. The L121-adjuvant also facilitated antigen delivery to the dendritic cells in the lymph nodes. Immunization of mice with the L121-adjuvant resulted in cell-mediated cytotoxic responses in the target cells, as detected by PhiPhiLux, a fluorogenic caspase substrate. Taken together, the L121-adjuvant improved the dynamics of protein delivery to antigen presenting cells, and also induced caspase activation, thereby illustrating the mechanism of antigen-specific CTL effects. PMID:25917678

  10. Equine infectious anemia virus-infected dendritic cells retain antigen presentation capability

    To determine if equine monocyte-derived dendritic cells (DC) were susceptible to equine infectious anemia virus (EIAV) infection, ex vivo-generated DC were infected with virus in vitro. EIAV antigen was detected by immunofluorescence 3 days post-infection with maximum antigen being detected on day 4, whereas there was no antigen detected in DC incubated with the same amount of heat-inactivated EIAV. No cytolytic activity was observed after EIAVWSU5 infection of DC. These monocyte-derived DC were more effective than macrophages and B cells in stimulating allogenic T lymphocytes. Both infected macrophages and DC stimulated similar levels of memory CTL responses in mixtures of CD8+ and CD4+ cells as detected with 51Cr-release assays indicating that EIAV infection of DC did not alter antigen presentation. However, EIAV-infected DC were more effective than infected macrophages when used to stimulate memory CTL in isolated CD8+ cells. The maintenance of antigen processing and presenting function by EIAV-infected DC in vitro suggests that this function is maintained during in vivo infection

  11. Expression cloning and chromosomal mapping of the leukocyte activation antigen CD97, a new seven-span transmembrane molecule of the secretin receptor superfamily with an unusual extracellular domain

    Hamann, J. [Univ. of Amsterdam (Netherlands)]|[Max Planck Society, Berlin-Buch (Germany); Hamann, D.; Lier, R.A.W. [Univ. of Amsterdam (Netherlands)] [and others

    1995-08-15

    CD97 is a monomeric glycoprotein of 75 to 85 kDa that is induced rapidly on the surface of most leukocytes upon activation. We herein report the isolation of a cDNA encoding human CD97 by expression cloning in COS cells. The 3-kb cDNA clone encodes a mature polypeptide chain of 722 amino acids with a predicted molecular mass of 79 kDa. Within the C-terminal part of the protein, a region with seven hydrophobic segments was identified, suggesting that CD97 is a seven-span transmembrane molecule. Sequence comparison indicates that CD97 is the first leukocyte Ag in a recently described superfamily that includes the receptors for secretin, calcitonin, and other mammalian and insect peptide hormones. Different from these receptors, CD97 has an extended extracellular region of 433 amino acids that possesses three N-terminal epidermal growth factor-like domains, two of them with a calcium-binding site, and single Arg-Gly-Asp (RGD) motif. The existence of structural elements characteristic for extracellular matrix proteins in a seven-span transmembrane molecule makes CD97 a receptor potentially involved in both adhesion and signaling processes early after leukocyte activation. The gene encoding CD97 is localized on chromosome 19 (19p13.12-13.2).

  12. CD4+ T cell-mediated presentation of non-infectious HIV-1virion antigens to HIV-specific CD8+ T cells

    XU Jian-qing; Franco Lori; Julianna Lisziewicz

    2006-01-01

    Background The mechanism of chronic immune activation and impairment of HIV-specific immune responses during chronic infection is not fully understood. However, it is known that high immune activation leads to more rapid progression to AIDS. We hypothesize that CD4+ T cell-mediated viral antigen presentation contributes to this pathologic immune activation in HIV-infected individuals.Methods HIV-specific T cells, responding to noninfectious HIV-1 virions as antigen, were measured by flow cytometric assays. These experimental conditions reflect the in vivo condition where noninfectious HIV-1 represents more than 99% of the antigens.Results CD4+ T cells purified from HIV-infected individuals were capable of cross presenting exogenous noninfectious HIV-1 virions to HIV-1-specific CD8+ T cells. Cross presentation required the entry of HIV-1 to CD4+ T cells and antigen translocation from endoplasmic reticulum to the Golgi complex. Blocking CD4+mediated activation of HIV-specific CD8+ T cells and redirecting the viral antigens to antigen presenting cells improved HIV-specific T cell responses.Conclusions One possible cause of chronic immune activation and impairment of HIV-1 specific T cell responses is represented by HIV-1 harboring CD4+ T cells cross presenting HIV-1 antigen to activate CD8+ T cells. This new mechanism provides the first evidence that cross presentation of noninfectious HIV-1. Virions play a role in the immunopathogenesis of HIV-1 infection.

  13. Follow-up of neurocysticercosis patients after treatment using an antigen detection ELISA

    Nguekam

    2003-03-01

    Full Text Available Seven patients with active neurocysticercosis (NCC received an eight days treatment with albendazole and were followed up using computed tomography (CT-scan and a monoclonal antibody based ELISA for the detection of circulating antigen (Ag-ELISA. Only three patients were cured as was shown by CT-scan and by the disappearance of circulating antigens one month after treatment. After a second course of albendazole therapy, two other patients became seronegative. CT-scan showed the disappearance of viable cysts in all persons who became seronegative whereas patients who were not cured remained seropositive. These preliminary results show that this Ag-ELISA is a promising technique for monitoring the success of treatment of NCC patients because of the excellent correlation between the presence of circulating antigens and of viable brain cysts.

  14. INTERACTION OF ANTIGEN AND ANTIBODY ON CORE-SHELL POLYMERIC MICROSPHERES

    Gang Li; Qing-bin Meng; Zhan-yong Li; Ying-li An; Xiao-xia Zhu

    2011-01-01

    Monodispersed microspheres with polystyrene as the core and poly(acrylamide-co-N-acryloxysuccinimide) as the shell were synthesized by a two-step surfactant-free emulsion copolymerization. The core-shell morphology of the microspheres was shown by scanning electron microscopy and transmission electron microscopy. Rabbit immunoglobulin G (as antigen) was covalently coupled onto the microspheres by the reaction between succinimide-activated ester groups on the shell of the microspheres and amino groups of the antigen molecules. The size of particles was characterized by dynamic light scattering technique and was found to vary upon bioconjugation and interaction with proteins. The binding process was shown to be specific to goat anti-rabbit immunoglobulin G (as antibody) and reversible upon the addition of free antigen into the system.

  15. Delivery of Exogenous Antigens to Induce Cytotoxic CD8+ T Lymphocyte Responses

    Julia Kim

    2010-01-01

    Full Text Available Vaccines intended to induce a cytotoxic CD8+ T-cell response are highly sought after. However, some of these vaccines can be problematic if they replicate in the host. An alternative strategy is to exploit cross-presentation of exogenous antigens to express peptides on major histocompatibility complex (MHC class I molecules. During cross-presentation, the delivered exogenous antigen can be taken up and processed through diverse mechanisms. Here, we will discuss the recent advances regarding the complex nature of the cross-priming process and the models that reflect its relevance in vivo. Moreover, we summarize current data that explore potential adjuvants and vaccine vectors that deliver antigens to activate CD8+ T cells relying on cross-presentation.

  16. Overlapping antigenic repertoires of variant antigens expressed on the surface of erythrocytes infected by Plasmodium falciparum

    Giha, H A; Staalsoe, T; Dodoo, D; Elhassan, I M; Roper, C; Satti, G M; Arnot, D E; Hviid, L; Theander, T G

    antibodies to some combinations of variant antigens but not to others. These results indicate that (1) a single infection will induce the production of antibodies recognizing several variants of surface-expressed antigens, (2) the repertoire of variable antigens expressed by different parasites is...

  17. INTRATHYMIC INOCULATION OF LIVER SPECIFIC ANTIGEN ALLEVIATES LIVER TRANSPLANT REJECTION

    贾长库; 郑树森; 朱有法

    2004-01-01

    Objective To study the effects of liver specific antigen (LSA) on liver allotransplantation rejection. Methods Orthotopic liver transplantation was performed in this study. Group Ⅰ: syngeneic control (Wistar-to-Wistar); Group Ⅱ: acute rejection (SD-to-Wistar). Group Ⅲ: thymic inoculation of SD rat LSA day 7 before transplantation. The observation of general condition and survival time, rejection grades and the NF-κB activity of splenocytes were used to analyze severity of acute rejection and immune state of animals in different groups. Results The general condition of group Ⅰ was fair post transplantation with no sign of rejection. All recipients of group Ⅱ died within days 9 to 13 post transplantation with median survival time of 10.7 ±1.37 days. As for group Ⅲ, 5 out of 6 recipients survived for a long period with remarkably better general condition than that of group Ⅱ. Its rejection grades were significantly lower than group Ⅱ (P< 0.05).NF-κB activity was only detected in group Ⅰ between days 5 and 7 after transplantation, whereas high activity of NF-κB was detected at all points in group Ⅱ and low NF-κB activity was detected in group Ⅲ which was significantly lower than that of group Ⅱ (P < 0.05). Conclusions LSA is an important transplantation antigen directly involved in the immunorejection of liver transplantation. Intrathymic inoculation of LSA can alleviate the rejection of liver allotransplantation,grafts survive for a period of time thereby, allowing a novel way to liver transplantation immunotolerance.

  18. ABO blood group antigens in oral mucosa. What is new?

    Dabelsteen, Erik

    2002-01-01

    Histo-blood group ABH (O) antigens are major alloantigens in humans. These antigens are widely distributed in human tissues and undergo changes in expression during cellular differentiation and malignant development. The ABH antigens have been characterized as terminal disaccharide determinants...... healing show similarly decreased expression of A/B antigens on migrating epithelial cells. Some studies suggest that the relationship between expression of blood group antigens and cell motility can be explained by different degrees of glycosylation of integrins. Changes in ABO expression in tumours have...

  19. A competitive-inhibiton radioimmunoassay for influenza virus envelope antigens

    A double-antibody competitive-inhibition radioimmunoassay for influenza virus envelope antigens is described. A viral antigen preparation from influenza A virus recombinant MRC11 [antigenically identical to A/Port Chalmers/1/73 (H3N2)] consisting of haemagglutinin and neuraminidase was labelled with radioiodine. Rabbit antisera were allowed to react with the labelled antigen and the resultant antigen-antibody complexes were precipitated with the appropriate antiglobulin. The competitive-inhibition radioimmunoassay very sensitively elucidated differences even among closely related influenza virus strains. Attempts have been made to eliminate neuraminidase from radioimmunoprecipitation to obtain a competitive-inhibition radioimmunoassay system for haemagglutinin alone. (author)

  20. Radionuclide-labelled antigens in serological epidemiology

    The feasibility of tests using radionuclide-labelled antigens in serological surveys was studied, with particular attention to the likely availability of facilities and personnel in the tropics and arctics, where measurements may be disturbed by climatic influences. The methodology required was to be simple, rapid and suitable for examining large numbers of sera, as for epidemological surveys. In the introduction, limitations of labelled antigen tests are discussed, the choice of radionuclide and measurement methods, test procedures and evaluation of results. Collection, preservation and shipment of speciments (serum, faeces, cerebrospinal fluid, sputum, etc.) are described. Experiments with bacteria and bacterial toxins (Enterobacteriaceae, vibrios, staphylococci, meningococci, etc.), with protozoa and metazoa (Entamoeba hystolytica, Schistosoma mansoni, Trypanosoma cruzi, Plasmodia and other parasites), with viruses (vaccinia, adeno-, polio-, and influenza viruses, etc.), and with fungi are discussed

  1. Toxicities of chimeric antigen receptor T cells: recognition and management.

    Brudno, Jennifer N; Kochenderfer, James N

    2016-06-30

    Chimeric antigen receptor (CAR) T cells can produce durable remissions in hematologic malignancies that are not responsive to standard therapies. Yet the use of CAR T cells is limited by potentially severe toxicities. Early case reports of unexpected organ damage and deaths following CAR T-cell therapy first highlighted the possible dangers of this new treatment. CAR T cells can potentially damage normal tissues by specifically targeting a tumor-associated antigen that is also expressed on those tissues. Cytokine release syndrome (CRS), a systemic inflammatory response caused by cytokines released by infused CAR T cells can lead to widespread reversible organ dysfunction. CRS is the most common type of toxicity caused by CAR T cells. Neurologic toxicity due to CAR T cells might in some cases have a different pathophysiology than CRS and requires different management. Aggressive supportive care is necessary for all patients experiencing CAR T-cell toxicities, with early intervention for hypotension and treatment of concurrent infections being essential. Interleukin-6 receptor blockade with tocilizumab remains the mainstay pharmacologic therapy for CRS, though indications for administration vary among centers. Corticosteroids should be reserved for neurologic toxicities and CRS not responsive to tocilizumab. Pharmacologic management is complicated by the risk of immunosuppressive therapy abrogating the antimalignancy activity of the CAR T cells. This review describes the toxicities caused by CAR T cells and reviews the published approaches used to manage toxicities. We present guidelines for treating patients experiencing CRS and other adverse events following CAR T-cell therapy. PMID:27207799

  2. Tumor-Associated Antigens for Specific Immunotherapy of Prostate Cancer

    Prostate cancer (PCa) is the most common noncutaneous cancer diagnosis and the second leading cause of cancer-related deaths among men in the United States. Effective treatment modalities for advanced metastatic PCa are limited. Immunotherapeutic strategies based on T cells and antibodies represent interesting approaches to prevent progression from localized to advanced PCa and to improve survival outcomes for patients with advanced disease. CD8+ cytotoxic T lymphocytes (CTLs) efficiently recognize and destroy tumor cells. CD4+ T cells augment the antigen-presenting capacity of dendritic cells and promote the expansion of tumor-reactive CTLs. Antibodies mediate their antitumor effects via antibody-dependent cellular cytotoxicity, activation of the complement system, improving the uptake of coated tumor cells by phagocytes, and the functional interference of biological pathways essential for tumor growth. Consequently, several tumor-associated antigens (TAAs) have been identified that represent promising targets for T cell- or antibody-based immunotherapy. These TAAs comprise proteins preferentially expressed in normal and malignant prostate tissues and molecules which are not predominantly restricted to the prostate, but are overexpressed in various tumor entities including PCa. Clinical trials provide evidence that specific immunotherapeutic strategies using such TAAs represent safe and feasible concepts for the induction of immunological and clinical responses in PCa patients. However, further improvement of the current approaches is required which may be achieved by combining T cell- and/or antibody-based strategies with radio-, hormone-, chemo- or antiangiogenic therapy

  3. Tumor-Associated Antigens for Specific Immunotherapy of Prostate Cancer

    Kiessling, Andrea [Biologics Safety and Disposition, Preclinical Safety, Translational Sciences, Novartis Institutes for BioMedical Research, Novartis Pharma AG, Werk Klybeck, Klybeckstraße 141, Basel CH-4057 (Switzerland); Wehner, Rebekka [Institute of Immunology, Medical Faculty, University of Technology Dresden, Fetscherstraße 74, Dresden 01307 (Germany); Füssel, Susanne [Department of Urology, Medical Faculty, University of Technology Dresden, Fetscherstraße 74, Dresden 01307 (Germany); Bachmann, Michael [Institute of Immunology, Medical Faculty, University of Technology Dresden, Fetscherstraße 74, Dresden 01307 (Germany); Wirth, Manfred P. [Department of Urology, Medical Faculty, University of Technology Dresden, Fetscherstraße 74, Dresden 01307 (Germany); Schmitz, Marc, E-mail: marc.schmitz@tu-dresden.de [Institute of Immunology, Medical Faculty, University of Technology Dresden, Fetscherstraße 74, Dresden 01307 (Germany)

    2012-02-22

    Prostate cancer (PCa) is the most common noncutaneous cancer diagnosis and the second leading cause of cancer-related deaths among men in the United States. Effective treatment modalities for advanced metastatic PCa are limited. Immunotherapeutic strategies based on T cells and antibodies represent interesting approaches to prevent progression from localized to advanced PCa and to improve survival outcomes for patients with advanced disease. CD8{sup +} cytotoxic T lymphocytes (CTLs) efficiently recognize and destroy tumor cells. CD4{sup +} T cells augment the antigen-presenting capacity of dendritic cells and promote the expansion of tumor-reactive CTLs. Antibodies mediate their antitumor effects via antibody-dependent cellular cytotoxicity, activation of the complement system, improving the uptake of coated tumor cells by phagocytes, and the functional interference of biological pathways essential for tumor growth. Consequently, several tumor-associated antigens (TAAs) have been identified that represent promising targets for T cell- or antibody-based immunotherapy. These TAAs comprise proteins preferentially expressed in normal and malignant prostate tissues and molecules which are not predominantly restricted to the prostate, but are overexpressed in various tumor entities including PCa. Clinical trials provide evidence that specific immunotherapeutic strategies using such TAAs represent safe and feasible concepts for the induction of immunological and clinical responses in PCa patients. However, further improvement of the current approaches is required which may be achieved by combining T cell- and/or antibody-based strategies with radio-, hormone-, chemo- or antiangiogenic therapy.

  4. Antigenic characterisation of lyssaviruses in South Africa

    Ernest Ngoepe; Christine Fehlner-Gardiner; Alex Wandeler; Claude Sabeta

    2014-01-01

    There are at least six Lyssavirus species that have been isolated in Africa, which include classical rabies virus, Lagos bat virus, Mokola virus, Duvenhage virus, Shimoni bat virus and Ikoma lyssavirus. In this retrospective study, an analysis of the antigenic reactivity patterns of lyssaviruses in South Africa against a panel of 15 anti-nucleoprotein monoclonal antibodies was undertaken. A total of 624 brain specimens, collected between 2005 and 2009, confirmed as containing lyssavirus anti...

  5. Antigenicity of low molecular weight surfactant species.

    Strayer, D. S.; Merritt, T A; Makunike, C.; Hallman, M

    1989-01-01

    The authors tested the antigenicity of human lung surfactant isolated from amniotic fluid. Mice and rabbits were immunized. Rabbit polyclonal antisera to these surfactant preparations were absorbed with normal human plasma proteins. Polyclonal antisera reacted with both high molecular weight (35 kd) surfactant apoprotein and to lower molecular weight species, both 18 kd and 9 kd. Mice were used to generate monoclonal antibodies to surfactant. Enzyme-linked immunosorbant assay was used to iden...

  6. Class II HLA antigens in multiple sclerosis.

    Miller, D H; Hornabrook, R W; Dagger, J; Fong, R

    1989-01-01

    HLA typing in Wellington revealed a stronger association of multiple sclerosis with DR2 than with DQw1. The association with DQw1 appeared to be due to linkage disequilibrium of this antigen with DR2. These results, when considered in conjunction with other studies, are most easily explained by the hypothesis that susceptibility to multiple sclerosis is influenced by multiple risk factors, with DR2 being an important risk factor in Caucasoid populations. PMID:2732726

  7. Yeast retrotransposon particles as antigen delivery systems.

    Kingsman, A J; Burns, N R; Layton, G T; Adams, S E

    1995-05-31

    The development of technologies to produce recombinant proteins for use in the pharmaceutical industry has made substantial advances, in particular in the area of generating antigens containing multiple copies of important immunological regions. One such antigen-carrier system is based on the ability of a protein encoded by the yeast retrotransposon, Ty, to self-assemble into virus-like particles. Ty-fusion proteins retain this ability to form particles, and a range of hybrid VLPs carrying a variety of heterologous antigens have been produced and shown to induce potent immune responses. In particular, hybrid VLPs carrying the core protein p24 of HIV (p24-VLPs) have been shown to induce antibody and T-cell proliferative responses in both experimental animals and human volunteers, and immunization of rabbits with VLPs carrying the principal neutralizing determinant of HIV (V3-VLPs) resulted in the induction of neutralizing antibody responses and T-cell proliferation. Further studies with V3-VLPs have shown that this particulate antigen stimulates enhanced V3-specific lymphoproliferative responses as compared to whole recombinant gp120 or to V3 peptide conjugated to albumin. The V3-VLPs also induce potent CTL responses following immunization of mice in the absence of adjuvant. These responses are MHC class I restricted and are mediated by CD8-positive cells. These observations therefore demonstrate that hybrid Ty-VLPs induce both humoral and cellular immune responses against HIV and suggest that these immunogens may be important in combatting AIDS and other infections. PMID:7625653

  8. Rationalisation of Legionella Urinary Antigen Testing.

    Lynch, Breda

    2014-01-01

    Introduction: Legionnaires’ is a severe pneumonia, the diagnosis of which can be confirmed by a positive Legionella Urinary Antigen (LUA) test. The British Thoracic Society has specific guidelines for its use. Incorrect LUA test requests can result in false-positive results while accumulating costs. Aims and Objectives: The aim is the rationalisation of LUA testing. The first objective is to educate clinicians on indications for testing reducing unnecessary orders. The second is to develop...

  9. The role of antigen in the development of B-cell chronic lymphocytic leukemia

    Hoogeboom, R.

    2013-01-01

    These studies strongly suggest that MALT-lymphomas and M-CLL in majority are highly selected for single extrinsic antigens and that these antigens can be both self-antigens and exo-antigens. Our finding that primary CLL cells are responsive to stimulation with their cognate antigen suggests that antigen-dependent BCR signaling may drive CLL expansion in vivo.

  10. Enhanced immune stimulation by a therapeutic lymphoma tumor antigen vaccine produced in insect cells involves mannose receptor targeting to antigen presenting cells.

    Betting, David J; Mu, Xi Y; Kafi, Kamran; McDonnel, Desmond; Rosas, Francisco; Gold, Daniel P; Timmerman, John M

    2009-01-01

    Therapeutic vaccination of lymphoma patients with tumor-specific immunoglobulin (idiotype, Id) coupled to the carrier protein keyhole limpet hemocyanin (Id-KLH) is undergoing clinical investigation, and methods to improve the immunogenicity of these and other protein tumor antigen vaccines are being sought. Id proteins can be produced via tumor-myeloma hybridomas or recombinant methods in mammalian, bacteria, or insect cells. We now demonstrate that terminal mannose residues, characteristic of recombinant proteins produced in insect cells, yield Id proteins with significantly enhanced immunostimulatory properties compared to Id proteins derived from mammalian cells. Recombinant baculovirus-infected insect cell-derived Id showed higher binding to and activation of human dendritic cells mediated by mannose receptors. In vivo, insect cell-derived Id elicited higher levels of tumor-specific CD8+ cytotoxic T lymphocyte (CTL) and improved eradication of pre-established murine lymphoma. Insect cell and mammalian Id generated similar levels of tumor-specific antibodies, showing no impairment in antibody responses to native tumor antigen despite the glycoslylation differences in the immunogen. Combining insect cell production and maleimide-based KLH conjugation offered the highest levels of anti-tumor immunity. Our data comparing sources of recombinant Id protein tumor antigens used in therapeutic cancer vaccines demonstrate that insect cell-derived antigens can offer several immunologic advantages over proteins derived from mammalian sources. PMID:19000731

  11. A Novel Chimeric Antigen Receptor Against Prostate Stem Cell Antigen Mediates Tumor Destruction in a Humanized Mouse Model of Pancreatic Cancer

    Lagisetty, Kiran H.; Tran, Eric; Zheng, Zhili; Gattinoni, Luca; Yu, Zhiya; Burns, William R.; Miermont, Anne M.; Teper, Yaroslav; Rudloff, Udo; Restifo, Nicholas P.; Feldman, Steven A.; Rosenberg, Steven A.; Morgan, Richard A.

    2014-01-01

    Abstract Despite advances in the understanding of its molecular pathophysiology, pancreatic cancer remains largely incurable, highlighting the need for novel therapies. We developed a chimeric antigen receptor (CAR) specific for prostate stem cell antigen (PSCA), a glycoprotein that is overexpressed in pancreatic cancer starting at early stages of malignant transformation. To optimize the CAR design, we used antigen-recognition domains derived from mouse or human antibodies, and intracellular signaling domains containing one or two T cell costimulatory elements, in addition to CD3zeta. Comparing multiple constructs established that the CAR based on human monoclonal antibody Ha1-4.117 had the greatest reactivity in vitro. To further analyze this CAR, we developed a human pancreatic cancer xenograft model and adoptively transferred CAR-engineered T cells into animals with established tumors. CAR-engineered human lymphocytes induced significant antitumor activity, and unlike what has been described for other CARs, a second-generation CAR (containing CD28 cosignaling domain) induced a more potent antitumor effect than a third-generation CAR (containing CD28 and 41BB cosignaling domains). While our results provide evidence to support PSCA as a target antigen for CAR-based immunotherapy of pancreatic cancer, the expression of PSCA on selected normal tissues could be a source of limiting toxicity. PMID:24694017

  12. Study of serum Helicobacter pylori soluble antigen

    吴勤动; 朱永良

    2002-01-01

    Objective:to explore a new serological method for detecting Helicobacter pylori(H.pylori) infection.Methods:Serum soluble antigen of H.pylori was detected by using avidin-biotin ELISA technique to evaluate the status of H.pylori infection and for comparison with rapid urease test(RUT).histologic examination and serology,Results:The sensitivity,specificity,positive predictive value and negative predictive value were 77.46% ,91.07%,91.67% and 76.12%,respectively.The prevalence rate of werum H. pylori soluble antigen in 138 patients undergong endoscopy was similar to the rate obtained by 14 C-UBT methods(P>0.05).Conclusions:The detection of serum H.pylori soluble antigen(HpSAg) could be used as a new serological method which is accurate,and convenient,not affected by the memorizing raction of serum antibody;is more sensitive,more specific and suitable for dinical diagriosis,and evaluation of eradication and for follow-up of H.pylori as well as for detection in children and pregnant women.

  13. Study of serum Helicobacter pylori soluble antigen

    吴勤动; 朱永良

    2002-01-01

    Objective: to explore a new serological method for detecting Helicobac ter pylori ( H. pylori ) infection. Methods: Serum soluble antigen of H. p ylor i was detected by using avidin-biotin ELISA technique to evaluate the status of H. pylori infection and for comparison with rapid urease test ( RUT ), histo logi c examination and serology. Results: The sensitivity, specificity, positive pred ictive value and negative predictive value were 77.46%, 91.07%, 91.67% a nd 76.12 %, respectively. The prevalence rate of serum H. pylori soluble antigen in 138 patients undergoing endoscopy was similar to the rate obtained by 14 C-UBT met hods ( P>0.05 ). Conclusions: The detection of serum H. pylori solub le antigen( HpSAg) could be used as a new serological method which is accurate, and convenie nt, not affected by the memorizing reaction of serum antibody; is more sensitive , m ore specific and suitable for clinical diagnosis, and evaluation of eradication and for follow-up of H. pylori as well as for detection in children and pre gnant women.

  14. Demonstration and characterization of tumor-associated antigenic components from cell membranes of a UV-induced mouse sarcoma using the macrophage-electrophoretic-mobility (MEM) test

    Purification of tumor-associated antigenic material from the ascites sarcoma cells was carried out by extraction with 3 M KCl and SDS-polyacrylamide gel electrophoresis (SDS-PAGE). The antigenic activity was assayed in the MEM test. Extraction of whole tumor cells with 3 M KCl results in preparations with low antigenic activity which on SDS-PAGE show a very heterogeneous composition of more than 2o protein bands. In comparing the antigenic activity of different subcellular fractions obtained by differential centrifugation of the homogenate, the antigenic activity could be attributed to the cell membrane fraction. With this cell membrane fraction, three extraction media - 3 M KCl, 2% Triton X-100, and 5% sodium cholate - were tested for their ability to extract selectively the antigenic membrane proteins. The Triton X-100 treatment sobubilized the greatest amount of membrane protein. Both Triton X-100 and sodium cholate, however, produced very heterogeneous protein extracts. In contrast, 3 M KCl extracted selectively three membrane components: a glycoprotein of high molecular weight and two low-molecular weight carbohydrate-free proteins. Removal of the KCl in the presence of Triton X-100 precipitates the carbohydrate-free proteins, while the glycoprotein remains in solution. Testing the components of the KCl extracts in the MEM test after isolation by preparative SDS-PAGE revealed antigenic activity only with the glycoprotein component. (author)

  15. Use of radiolabeled antibodies to carcinoembryonic antigen for the detection and localization of diverse cancers by external photoscanning

    To determine whether tumors containing carcinoembryonic antigen could be detected by administration of a radiolabeled, affinity-purified, goat IgG having 70% immunoreactivity against carcinoembryonic antigen, 18 patients with a history of cancer of diverse histopathology received an average total dose of 1.0 mCi of 131I-labeled IgG. Total-body photoscans were performed with a gamma scintillation camera at various intervals after administration of the radioactive antibody. Ordinary photoscans proved difficult to interpret because of blood-pool background radioactivity, thus necessitating the computer subtraction of radioactive blood-pool agents from the antibody's 131I activity. Tumor location could be demonstrated at 48 hours after injection in almost all cases studied. The scans were negative in patients without demonstrable tumors or with tumors apparently devoid of carcinoembryonic antigen. Circulating antigen levels of up to 350 ng per milliliter did not prevent successful tumor imaging after injection of the radioantibody

  16. The radiocontrast molecule in anaphylaxis: a surprising antigen.

    Lasser, Elliott C

    2004-01-01

    X-ray contrast media are individually injected into human blood vessels in greater quantities than any other pharmacological substance. Adverse reactions to these substances have heretofore been considered anaphylactoid in nature. Others and we have demonstrated that the mechanisms involved are multifactorial and may involve activation of mast cells and basophils, activation of the complement system, activation of the contact system, and the conversion of L-arginine into nitric oxide. Appropriate pretreatment with corticosteriods will diminish the incidence of reactions. Most recently we have demonstrated that the contrast media function as 'pseudoantigens' (PsA). They can combine with antibodies, but cannot themselves produce antibodies. This property appears to be dependent on aggregation in high concentrations and varies with the individual media. It furthermore appears to be non-specific in relation to antibodies, and suggests that binding occurs to the Fc portion of immunoglobulins. We have now demonstrated that the least toxic of current media demonstrate the best antibody binding and in sufficient concentration can inhibit contrast induced mast cell activation and/or non-contrast antigen induced mast cell activation, apparently due to in vivo pseudoantigen excess. In lesser concentrations and/or lesser binding, the media can trigger mast cell activation. PMID:15025400

  17. Architecture of the DNA polymerase B-proliferating cell nuclear antigen (PCNA)-DNA ternary complex

    Mayanagi, Kouta; Kiyonari, Shinichi; Nishida, Hirokazu; Saito, Mihoko; Kohda, Daisuke; Ishino, Yoshizumi; Shirai, Tsuyoshi; Morikawa, Kosuke

    2011-01-01

    DNA replication in archaea and eukaryotes is executed by family B DNA polymerases, which exhibit full activity when complexed with the DNA clamp, proliferating cell nuclear antigen (PCNA). This replication enzyme consists of the polymerase and exonuclease moieties responsible for DNA synthesis and editing (proofreading), respectively. Because of the editing activity, this enzyme ensures the high fidelity of DNA replication. However, it remains unclear how the PCNA-complexed enzyme temporally ...

  18. New diagnostic antigens for early trichinellosis: the excretory-secretory antigens of Trichinella spiralis intestinal infective larvae.

    Sun, Ge Ge; Liu, Ruo Dan; Wang, Zhong Quan; Jiang, Peng; Wang, Li; Liu, Xiao Lin; Liu, Chun Yin; Zhang, Xi; Cui, Jing

    2015-12-01

    The excretory-secretory (ES) antigens from Trichinella spiralis muscle larvae (ML) are the most commonly used diagnostic antigens for trichinellosis, but anti-Trichinella IgG antibodies cannot be detected until 2-3 weeks after infection; there is an obvious window period between Trichinella infection and antibody positivity. Intestinal infective larvae (IIL) are the first invasive stage during Trichinella infection, and their ES antigens are firstly exposed to the immune system and might be the early diagnostic markers of trichinellosis. The aim of this study was to evaluate the early diagnostic values of IIL ES antigens for trichinellosis. The IIL were collected from intestines of infected mice at 6 h postinfection (hpi), and IIL ES antigens were prepared by incubation for 18 h. Anti-Trichinella IgG antibodies in mice infected with 100 ML were detectable by ELISA with IIL ES antigens as soon as 10 days postinfection (dpi), but ELISA with ML ES antigens did not permit detection of infected mice before 12 dpi. When the sera of patients with trichinellosis at 19 dpi were assayed, the sensitivity (100 %) of ELISA with IIL ES antigens was evidently higher than 75 % of ELISA with ML ES antigens (P < 0.05) The specificity (96.86 %) of ELISA with IIL ES antigens was also higher than 89.31 % of ELISA with ML ES antigens (P < 0.05). The IIL ES antigens provided a new source of diagnostic antigens and could be considered as a potential early diagnostic antigen for trichinellosis. PMID:26342828

  19. Exosome targeting of tumor antigens expressed by cancer vaccines can improve antigen immunogenicity and therapeutic efficacy.

    Rountree, Ryan B; Mandl, Stefanie J; Nachtwey, James M; Dalpozzo, Katie; Do, Lisa; Lombardo, John R; Schoonmaker, Peter L; Brinkmann, Kay; Dirmeier, Ulrike; Laus, Reiner; Delcayre, Alain

    2011-08-01

    MVA-BN-PRO (BN ImmunoTherapeutics) is a candidate immunotherapy product for the treatment of prostate cancer. It encodes 2 tumor-associated antigens, prostate-specific antigen (PSA), and prostatic acid phosphatase (PAP), and is derived from the highly attenuated modified vaccinia Ankara (MVA) virus stock known as MVA-BN. Past work has shown that the immunogenicity of antigens can be improved by targeting their localization to exosomes, which are small, 50- to 100-nm diameter vesicles secreted by most cell types. Exosome targeting is achieved by fusing the antigen to the C1C2 domain of the lactadherin protein. To test whether exosome targeting would improve the immunogenicity of PSA and PAP, 2 additional versions of MVA-BN-PRO were produced, targeting either PSA (MVA-BN-PSA-C1C2) or PAP (MVA-BN-PAP-C1C2) to exosomes, while leaving the second transgene untargeted. Treatment of mice with MVA-BN-PAP-C1C2 led to a striking increase in the immune response against PAP. Anti-PAP antibody titers developed more rapidly and reached levels that were 10- to 100-fold higher than those for mice treated with MVA-BN-PRO. Furthermore, treatment with MVA-BN-PAP-C1C2 increased the frequency of PAP-specific T cells 5-fold compared with mice treated with MVA-BN-PRO. These improvements translated into a greater frequency of tumor rejection in a PAP-expressing solid tumor model. Likewise, treatment with MVA-BN-PSA-C1C2 increased the antigenicity of PSA compared with treatment with MVA-BN-PRO and resulted in a trend of improved antitumor efficacy in a PSA-expressing tumor model. These experiments confirm that targeting antigen localization to exosomes is a viable approach for improving the therapeutic potential of MVA-BN-PRO in humans. PMID:21670078

  20. Genetic diversity and antigenicity variation of Babesia bovis merozoite surface antigen-1 (MSA-1) in Thailand.

    Tattiyapong, Muncharee; Sivakumar, Thillaiampalam; Takemae, Hitoshi; Simking, Pacharathon; Jittapalapong, Sathaporn; Igarashi, Ikuo; Yokoyama, Naoaki

    2016-07-01

    Babesia bovis, an intraerythrocytic protozoan parasite, causes severe clinical disease in cattle worldwide. The genetic diversity of parasite antigens often results in different immune profiles in infected animals, hindering efforts to develop immune control methodologies against the B. bovis infection. In this study, we analyzed the genetic diversity of the merozoite surface antigen-1 (msa-1) gene using 162 B. bovis-positive blood DNA samples sourced from cattle populations reared in different geographical regions of Thailand. The identity scores shared among 93 msa-1 gene sequences isolated by PCR amplification were 43.5-100%, and the similarity values among the translated amino acid sequences were 42.8-100%. Of 23 total clades detected in our phylogenetic analysis, Thai msa-1 gene sequences occurred in 18 clades; seven among them were composed of sequences exclusively from Thailand. To investigate differential antigenicity of isolated MSA-1 proteins, we expressed and purified eight recombinant MSA-1 (rMSA-1) proteins, including an rMSA-1 from B. bovis Texas (T2Bo) strain and seven rMSA-1 proteins based on the Thai msa-1 sequences. When these antigens were analyzed in a western blot assay, anti-T2Bo cattle serum strongly reacted with the rMSA-1 from T2Bo, as well as with three other rMSA-1 proteins that shared 54.9-68.4% sequence similarity with T2Bo MSA-1. In contrast, no or weak reactivity was observed for the remaining rMSA-1 proteins, which shared low sequence similarity (35.0-39.7%) with T2Bo MSA-1. While demonstrating the high genetic diversity of the B. bovis msa-1 gene in Thailand, the present findings suggest that the genetic diversity results in antigenicity variations among the MSA-1 antigens of B. bovis in Thailand. PMID:27101782

  1. The T-cell anergy induced by Leishmania amazonensis antigens is related with defective antigen presentation and apoptosis

    Roberta O. Pinheiro

    2004-09-01

    Full Text Available Leishmania amazonensis is the main agent of diffuse cutaneous leishmaniasis, a disease associated with anergic immune responses. In this study we show that the crude antigen of Leishmania amazonensis (LaAg but not L. braziliensis promastigotes (LbAg contains substances that suppress mitogenic and spontaneous proliferative responses of T cells. The suppressive substances in LaAg are thermoresistant (100ºC/1h and partially dependent on protease activity. T cell anergy was not due to a decreased production of growth factors as it was not reverted by addition of exogenous IL-2, IL-4, IFN-gamma or IL-12. LaAg did not inhibit anti-CD3-induced T cell activation, suggesting that anergy was due to a defect in antigen presentation. It was also not due to cell necrosis, but was accompanied by expressive DNA fragmentation in lymph node cells, indicative of apoptosis. Although pre-incubation of macrophages with LaAg prevented their capacity to present antigens, this effect was not due to apoptosis of the former. These results suggest that the T cell anergy found in diffuse leishmaniasis may be the result of parasite antigen-driven apoptosis of those cells following defective antigen presentation.A Leishmania amazonensis é o principal agente etiológico da leishmaniose cutânea difusa, uma doença associada a respostas imunes anérgicas. Neste estudo nós mostramos que o extrato bruto de promastigotas de Leishmania amazonensis (LaAg, mas não de L. braziliensis (LbAg, contém substâncias que suprimem respostas proliferativas, espontâneas e mitogênicas, de células T. As substâncias supressoras no LaAg são termo-resistentes (100°C/1h e parcialmente dependentes da atividade de proteases. A anergia de células T não foi devida à diminuição na produção de fatores de crescimento, uma vez que não foi revertida pela adição de: IL-2, IL-4, IFN-gama ou IL-12. O LaAg não inibiu a ativação de células T induzida por anti-CD3, sugerindo que a anergia

  2. Viral Escape Mutant Epitope Maintains TCR Affinity for Antigen yet Curtails CD8 T Cell Responses

    Shorter, Shayla K.; Schnell, Frederick J.; McMaster, Sean R.; Pinelli, David F.; Andargachew, Rakieb; Evavold, Brian D.

    2016-01-01

    T cells have the remarkable ability to recognize antigen with great specificity and in turn mount an appropriate and robust immune response. Critical to this process is the initial T cell antigen recognition and subsequent signal transduction events. This antigen recognition can be modulated at the site of TCR interaction with peptide:major histocompatibility (pMHC) or peptide interaction with the MHC molecule. Both events could have a range of effects on T cell fate. Though responses to antigens that bind sub-optimally to TCR, known as altered peptide ligands (APL), have been studied extensively, the impact of disrupting antigen binding to MHC has been highlighted to a lesser extent and is usually considered to result in complete loss of epitope recognition. Here we present a model of viral evasion from CD8 T cell immuno-surveillance by a lymphocytic choriomeningitis virus (LCMV) escape mutant with an epitope for which TCR affinity for pMHC remains high but where the antigenic peptide binds sub optimally to MHC. Despite high TCR affinity for variant epitope, levels of interferon regulatory factor-4 (IRF4) are not sustained in response to the variant indicating differences in perceived TCR signal strength. The CD8+ T cell response to the variant epitope is characterized by early proliferation and up-regulation of activation markers. Interestingly, this response is not maintained and is characterized by a lack in IL-2 and IFNγ production, increased apoptosis and an abrogated glycolytic response. We show that disrupting the stability of peptide in MHC can effectively disrupt TCR signal strength despite unchanged affinity for TCR and can significantly impact the CD8+ T cell response to a viral escape mutant. PMID:26915099

  3. A population dynamics analysis of the interaction between adaptive regulatory T cells and antigen presenting cells.

    David Fouchet

    Full Text Available BACKGROUND: Regulatory T cells are central actors in the maintenance of tolerance of self-antigens or allergens and in the regulation of the intensity of the immune response during infections by pathogens. An understanding of the network of the interaction between regulatory T cells, antigen presenting cells and effector T cells is starting to emerge. Dynamical systems analysis can help to understand the dynamical properties of an interaction network and can shed light on the different tasks that can be accomplished by a network. METHODOLOGY AND PRINCIPAL FINDINGS: We used a mathematical model to describe a interaction network of adaptive regulatory T cells, in which mature precursor T cells may differentiate into either adaptive regulatory T cells or effector T cells, depending on the activation state of the cell by which the antigen was presented. Using an equilibrium analysis of the mathematical model we show that, for some parameters, the network has two stable equilibrium states: one in which effector T cells are strongly regulated by regulatory T cells and another in which effector T cells are not regulated because the regulatory T cell population is vanishingly small. We then simulate different types of perturbations, such as the introduction of an antigen into a virgin system, and look at the state into which the system falls. We find that whether or not the interaction network switches from the regulated (tolerant state to the unregulated state depends on the strength of the antigenic stimulus and the state from which the network has been perturbed. CONCLUSION/SIGNIFICANCE: Our findings suggest that the interaction network studied in this paper plays an essential part in generating and maintaining tolerance against allergens and self-antigens.

  4. Antigenic characterization of Brazilian bovine viral diarrhea virus isolates by monoclonal antibodies and cross-neutralization

    Botton S.A.

    1998-01-01

    Full Text Available Nineteen Brazilian isolates of bovine viral diarrhea virus (BVDV were characterized antigenically with a panel of 19 monoclonal antibodies (mAbs (Corapi WV, Donis RO and Dubovi EJ (1990 American Journal of Veterinary Research, 55: 1388-1394. Eight isolates were further characterized by cross-neutralization using sheep monospecific antisera. Analysis of mAb binding to viral antigens by indirect immunofluorescence revealed distinct patterns of reactivity among the native viruses. Local isolates differed from the prototype Singer strain in recognition by up to 14 mAbs. Only two mAbs - one to the non-structural protein NS23/p125 and another to the envelope glycoprotein E0/gp48 - recognized 100% of the isolates. No isolate was recognized by more than 14 mAbs and twelve viruses reacted with 10 or less mAbs. mAbs to the major envelope glycoprotein E2/gp53 revealed a particularly high degree of antigenic variability in this glycoprotein. Nine isolates (47.3% reacted with three or less of 10 E2/gp53 mAbs, and one isolate was not recognized by any of these mAbs. Virus-specific antisera to eight isolates plus three standard BVDV strains raised in lambs had virus-neutralizing titers ranging from 400 to 3200 against the homologous virus. Nonetheless, many antisera showed significantly reduced neutralizing activity when tested against heterologous viruses. Up to 128-fold differences in cross-neutralization titers were observed for some pairs of viruses. When the coefficient of antigenic similarity (R was calculated, 49 of 66 comparisons (74.24% between viruses resulted in R values that antigenically distinguish strains. Moreover, one isolate had R values suggesting that it belongs to a distinct serologic group. The marked antigenic diversity observed among Brazilian BVDV isolates should be considered when planning diagnostic and immunization strategies.

  5. Viral Escape Mutant Epitope Maintains TCR Affinity for Antigen yet Curtails CD8 T Cell Responses.

    Shayla K Shorter

    Full Text Available T cells have the remarkable ability to recognize antigen with great specificity and in turn mount an appropriate and robust immune response. Critical to this process is the initial T cell antigen recognition and subsequent signal transduction events. This antigen recognition can be modulated at the site of TCR interaction with peptide:major histocompatibility (pMHC or peptide interaction with the MHC molecule. Both events could have a range of effects on T cell fate. Though responses to antigens that bind sub-optimally to TCR, known as altered peptide ligands (APL, have been studied extensively, the impact of disrupting antigen binding to MHC has been highlighted to a lesser extent and is usually considered to result in complete loss of epitope recognition. Here we present a model of viral evasion from CD8 T cell immuno-surveillance by a lymphocytic choriomeningitis virus (LCMV escape mutant with an epitope for which TCR affinity for pMHC remains high but where the antigenic peptide binds sub optimally to MHC. Despite high TCR affinity for variant epitope, levels of interferon regulatory factor-4 (IRF4 are not sustained in response to the variant indicating differences in perceived TCR signal strength. The CD8+ T cell response to the variant epitope is characterized by early proliferation and up-regulation of activation markers. Interestingly, this response is not maintained and is characterized by a lack in IL-2 and IFNγ production, increased apoptosis and an abrogated glycolytic response. We show that disrupting the stability of peptide in MHC can effectively disrupt TCR signal strength despite unchanged affinity for TCR and can significantly impact the CD8+ T cell response to a viral escape mutant.

  6. Abnormal antigens in breast cancer tissues and production of monoclonal antibodies against one of these antigens

    Breast cancer is associated with up regulation, down regulation of normal antigens or abnormal antigens. These antigens are very useful candidates as targets for the different breast cancer therapies and for vaccination trials. This study was done to characterize abnormal antigens, extract one of them and to produce monoclonal antibodies against the extracted antigen. One hundred and twenty Sudanese female patients were included in this study after informed consent. The mean age was 47. 2 years (16-80). Two tissue samples were obtained from each patient and they were confirmed as normal and cancerous breast tissues microscopically. 2D PAGE was used to analyze the protein content of samples. LC/MS and nr. fast a database search were used for separation and indentification of the abnormal proteins. Three different patterns of 2D Page results were obtained, the first pattern involved detection of four abnormal proteins in 26.7% of the patient cancerous tissues while they were undetected in the normal tissues of the same patients. In the second 2D PAGE result pattern the cancerous and the normal tissues of 67.5% patients were identical and they did not contain the four abnormal proteins while the third 2D PAGE pattern involved the presence of two abnormal antigens (from the four) in the cancerous tissues of 5.8% of the patients and they were absent from the normal tissues of the same patients. The four abnormal proteins were identified as, human Thioredoxin (D60nmutant), x-ray crystal structure of human galectin-1, retrocopy of tropomyosin 3(rc TPM3) and beta-tropomyosin (isoform 2). The primary and the secondary structures were obtained from the SWISSPROT and the PDB databases. Beta tropomyosin spot was extracted and used as antigen for monoclonal antibody production. Monoclonal antibody against beta- tropomyosin with a concentration of 0.35 mg/ml and a G11 anti beta-tropomyosin hybridoma cell line were produced. The monoclonal antibody was with single bad and

  7. Photoaffinity labeling demonstrates binding between Ia molecules and nominal antigen on antigen-presenting cells.

    Phillips, M L; Yip, C C; Shevach, E M; Delovitch, T L

    1986-01-01

    We have used radioiodinated photoreactive bovine insulin as antigen to examine the molecular nature of immunogenic complexes that form on antigen-presenting cells. The probe was allowed to bind to either insulin-presenting B-hybridoma cells, lipopolysaccharide-stimulated blasts, or bovine insulin-specific helper-T-hybridoma cells in the dark. Samples were then exposed to light to induce crosslinkage, solubilized, and analyzed by gel electrophoresis. Two protein bands at about 36 kDa and 27 kD...

  8. Seroreactivity of Salmonella-infected cattle herds against a fimbrial antigen in comparison with lipopolysaccharide antigens

    Hoorfar, Jeffrey; Lind, Peter; Bell, M.M.; Thorns, C.J.

    1996-01-01

    The IgG seroreaction of Salmonella-infected cattle herds against a fimbrial antigen (SEF14) was compared with that against lipopolysaccharide (LPS) antigens. Sera from 23 dairy herds (n = 205) from an island with no occurrence of salmonellosis, four herds (n = 303) with recent outbreaks of S....... dublin and four herds (n = 168) with recent outbreaks of S. typhimurium, were tested in a SEF14-ELISA, S. dublin LPS (0:1, 9, 12) ELISA and S. typhimurium LPS (0:1, 4, 5; 12) ELISA. At a cut-off OD of 0.5, only one of the animals tested from the salmonellosis-free island showed significant seroreaction...

  9. A novel cancer testis antigen protein phosphates gamma 2

    A novel cancer-testis antigen PP1a2, which is a serine/threonine phosphatase and known to regulate sperm motility and sperm maturation during spermeogenesis. Here we have identified PP1a2 as a cancer biomarker in Cervical (C33, Hela), Prostate (PC3, DU145) and Ovarian (PA1) cancer cell lines. PP1a2 expression was also found in Human Embryonic Kidney (HEK 293) cell lines. As a result PP1a2 was found to be a marker of germ cells, cancerous cells as well as embryonic cells. This invention led to the theory that aberrant expression of germline genes in cancer reflects the activation of the silenced gametogenic programme in somatic cells, and that this programmatic acquisition is one of the driving forces of tumorigenesis. (author)

  10. Quantitating protein synthesis, degradation, and endogenous antigen processing.

    Princiotta, Michael F; Finzi, Diana; Qian, Shu-Bing; Gibbs, James; Schuchmann, Sebastian; Buttgereit, Frank; Bennink, Jack R; Yewdell, Jonathan W

    2003-03-01

    Using L929 cells, we quantitated the macroeconomics of protein synthesis and degradation and the microeconomics of producing MHC class I associated peptides from viral translation products. To maintain a content of 2.6 x 10(9) proteins, each cell's 6 x 10(6) ribosomes produce 4 x 10(6) proteins min(-1). Each of the cell's 8 x 10(5) proteasomes degrades 2.5 substrates min(-1), creating one MHC class I-peptide complex for each 500-3000 viral translation products degraded. The efficiency of complex formation is similar in dendritic cells and macrophages, which play a critical role in activating T cells in vivo. Proteasomes create antigenic peptides at different efficiencies from two distinct substrate pools: rapidly degraded newly synthesized proteins that clearly represent defective ribosomal products (DRiPs) and a less rapidly degraded pool in which DRiPs may also predominate. PMID:12648452

  11. A role for NADPH oxidase in antigen presentation

    Gail J Gardiner

    2013-09-01

    Full Text Available The nicotinamide adenine dinucleotide phosphate (NADPH oxidase expressed in phagocytes is a multi-subunit enzyme complex that generates superoxide (O2.-. This radical is an important precursor of hydrogen peroxide (H2O2 and other reactive oxygen species (ROS needed for microbicidal activity during innate immune responses. Inherited defects in NADPH oxidase give rise to chronic granulomatous disease (CGD, a primary immunodeficiency characterized by recurrent infections and granulomatous inflammation. Interestingly, CGD, CGD carrier status, and oxidase gene polymorphisms have all been associated with autoinflammatory and autoimmune disorders, suggesting a potential role for NADPH oxidase in regulating adaptive immune responses. Here, NADPH oxidase function in antigen processing and presentation is reviewed. NADPH oxidase influences dendritic cell (DC crosspresentation by major histocompatibility complex class I molecules (MHC-I through regulation of the phagosomal microenvironment, while in B lymphocytes, NADPH oxidase alters epitope selection by major histocompatibility complex class II molecules (MHC-II.

  12. Human leukocyte antigen-DO regulates surface presentation of human leukocyte antigen class II-restricted antigens on B cell malignancies

    Kremer, A.N.; Meijden, E.D. van der; Honders, M.W.; Pont, M.J.; Goeman, J.J.; Falkenburg, J.H.F.; Griffioen, M.

    2014-01-01

    Hematological malignancies often express surface HLA class II, making them attractive targets for CD4+ T cell therapy. We previously demonstrated that HLA class II ligands can be divided into DM-resistant and DM-sensitive antigens. In contrast to presentation of DM-resistant antigens, presentation o

  13. Synergistic immune responses induced by endogenous retrovirus and herpesvirus antigens result in increased production of inflammatory cytokines in multiple sclerosis patients

    Brudek, Tomasz; Christensen, Tove; Hansen, Hans Jacob; Petersen, Thor; Møller-Larsen, Anné

    2008-01-01

    Human endogenous retroviruses (HERV) and herpesviruses are increasingly associated with the pathogenesis of the neurological inflammatory disease multiple sclerosis (MS). Herpesviruses are capable of HERV activation and simultaneous presence of HERV and herpesvirus antigens have a synergistic...

  14. Antigen-induced and non-antigen-induced histamine release from rat mast cells sensitized with mouse antiserum.

    Kurose,Masao

    1981-10-01

    Full Text Available Marked IgE-mediated histamine release from rat mast cells sensitized in vitro with mouse antiserum occurs in the presence of added Ca++ and phosphatidylserine (PS, although a considerable degree of antigen-induced histamine release which may utilize intracellular or cell-bound calcium is also observed. The decay in the responsiveness to Ca++ of the sensitized cells stimulated by antigen in Ca++-free medium in the presence of PS is relatively slow, and maximum release is produced by Ca++ added 1 min after antigen. Histamine release also occurs when Ca++ is added after PS in the absence of antigen to the sensitized cells suspended in Ca++-free medium. Unlike the antigen-induced release, the intensity of this non-antigen-induced release varies depending on both mast-cell and antiserum pools. A heat-labile factor(s, which is different from antigen-specific IgE antibody and is also contained in normal mouse serum, is involved in this reaction. In the antigen-nondependent (PS + Ca++-induced release, no decay in the responsiveness to Ca++ is observed after PS addition. Both the antigen-induced and non-antigen-induced release are completed fairly rapidly and are dependent of temperature, pH and energy.

  15. Galactosylated LDL nanoparticles: a novel targeting delivery system to deliver antigen to macrophages and enhance antigen specific T cell responses.

    Wu, Fang; Wuensch, Sherry A; Azadniv, Mitra; Ebrahimkhani, Mohammad R; Crispe, I Nicholas

    2009-01-01

    We aim to define the role of Kupffer cells in intrahepatic antigen presentation, using the selective delivery of antigen to Kupffer cells rather than other populations of liver antigen-presenting cells. To achieve this we developed a novel antigen delivery system that can target antigens to macrophages, based on a galactosylated low-density lipoprotein nanoscale platform. Antigen was delivered via the galactose particle receptor (GPr), internalized, degraded and presented to T cells. The conjugation of fluoresceinated ovalbumin (FLUO-OVA) and lactobionic acid with LDL resulted in a substantially increased uptake of FLUO-OVA by murine macrophage-like ANA1 cells in preference to NIH3T3 cells, and by primary peritoneal macrophages in preference to primary hepatic stellate cells. Such preferential uptake led to enhanced proliferation of OVA specific T cells, showing that the galactosylated LDL nanoscale platform is a successful antigen carrier, targeting antigen to macrophages but not to all categories of antigen presenting cells. This system will allow targeted delivery of antigen to macrophages in the liver and elsewhere, addressing the question of the role of Kupffer cells in liver immunology. It may also be an effective way of delivering drugs or vaccines directly at macrophages. PMID:19637876

  16. 猪骨髓基质抗原2基因的克隆、表达及生物学活性研究%Molecular Cloning and Expression of Bone Marrow Stromal Antigen-2 and Detection of Its Biological Activity

    张廷虹; 赵协; 曹广明; 张振杰; 常维山

    2012-01-01

    研究目的是克隆猪骨髓基质抗原2 (Bonc marrow stromal antigen 2,BST- 2)基因并进行真核表达,获得具有抗病毒活性的重组BST-2蛋白.研究通过RT-PCR从猪瘟弱毒疫苗和聚肌胞(Poly Ⅰ:C)刺激的猪肾细胞(PK-15)中扩增出猪BST-2 cDNA,克隆至真核表达载体pcDNA3.1/V5-His,构建重组表达质粒pcDNA-BST-2,转染HEK293T细胞,纯化BST-2蛋白并经Bradford法定量,Western blot检测,研究BST-2抗病毒生物学活性.酶切鉴定和核酸序列测定证实pcDNA-BST-2真核表达质粒构建成功,转染HEK293T细胞后,经间接免疫荧光能够检测到绿色荧光.生物学活性测定重组BST-2蛋白具有一定的抗水泡性口炎病毒(Vesicular stomatitis virus,VSV)、H9禽流感病毒(Avian influenza virus,AIV)及猪繁殖与呼吸综合症病毒(Porcine reproductive and respiratory syndrome virus,PRRSV)的活性.结果表明,重组BST-2具有一定抗病毒生物功能,为进一步研究重组BST 2蛋白的活性以及BST-2抗病毒药物研究奠定了基础.%To clone porcine bone marrow stromal antigen-2 (BST-2) gene, construct its recombinant eu-karyotic expression plasmid and induce the expression of the fusion antiviral protein, we amplified BST-2 gene by RT-PCR from the total RNA extracted from PK15 cells. The recombinant expression plasmid pcDNA-BST-2 was constructed and then was transfected into HEK293T cells to expresse the BST-2 fusion protein. Western blot and indirect immunofluorescence assay ( IFA) were performed, and the biological activity was detected. The results showed that the construction of recombinant plasmid pcDNA-BST-2 was confirmed by restriction enzyme digestion and sequencing. The expressed product had antiviral activity a-gainst Vesicular stomatitis virus (VSV), Avian influenza virus (AIV) and Porcine reproductive and respiratory syndrome virus (PRRSV). In conclusion, the research paves the way for further research on bioac-tivity assayand antiviral medication.

  17. Tissue distribution of histo-blood group antigens

    Ravn, V; Dabelsteen, Erik

    2000-01-01

    The introduction of immunohistochemical techniques and monoclonal antibodies to specific carbohydrate epitopes has made it possible to study in detail the tissue distribution of histo-blood group antigens and related carbohydrate structures. The present paper summarizes the available data...... concerning the histological distribution of histo-blood group antigens and their precursor structures in normal human tissues. Studies performed have concentrated on carbohydrate antigens related to the ABO, Lewis, and TTn blood group systems, i.e. histo-blood group antigens carried by type 1, 2, and 3 chain...... carrier carbohydrate chains. Histo-blood group antigens are found in most epithelial tissues. Meanwhile, several factors influence the type, the amount, and the histological distribution of histoblood group antigens, i.e. the ABO, Lewis, and saliva-secretor type of the individual, and the cell- and tissue...

  18. Identification, characterization and immunogenicity of an O-antigen capsular polysaccharide of Francisella tularensis.

    Michael A Apicella

    Full Text Available Capsular polysaccharides are important factors in bacterial pathogenesis and have been the target of a number of successful vaccines. Francisella tularensis has been considered to express a capsular antigen but none has been isolated or characterized. We have developed a monoclonal antibody, 11B7, which recognizes the capsular polysaccharide of F. tularensis migrating on Western blot as a diffuse band between 100 kDa and 250 kDa. The capsule stains poorly on SDS-PAGE with silver stain but can be visualized using ProQ Emerald glycoprotein stain. The capsule appears to be highly conserved among strains of F. tularensis as antibody 11B7 bound to the capsule of 14 of 14 F. tularensis type A and B strains on Western blot. The capsular material can be isolated essentially free of LPS, is phenol and proteinase K resistant, ethanol precipitable and does not dissociate in sodium dodecyl sulfate. Immunoelectron microscopy with colloidal gold demonstrates 11B7 circumferentially staining the surface of F. tularensis which is typical of a polysaccharide capsule. Mass spectrometry, compositional analysis and NMR indicate that the capsule is composed of a polymer of the tetrasaccharide repeat, 4-alpha-D-GalNAcAN-(1->4-alpha-D-GalNAcAN-(1->3-beta-D-QuiNAc-(1->2-beta-D-Qui4NFm-(1-, which is identical to the previously described F. tularensis O-antigen subunit. This indicates that the F. tularensis capsule can be classified as an O-antigen capsular polysaccharide. Our studies indicate that F. tularensis O-antigen glycosyltransferase mutants do not make a capsule. An F. tularensis acyltransferase and an O-antigen polymerase mutant had no evidence of an O-antigen but expressed a capsular antigen. Passive immunization of BALB/c mice with 75 microg of 11B7 protected against a 150 fold lethal challenge of F. tularensis LVS. Active immunization of BALB/c mice with 10 microg of capsule showed a similar level of protection. These studies demonstrate that F. tularensis

  19. Blood group antigen studies using CdTe quantum dots and flow cytometry

    Cabral Filho PE

    2015-07-01

    Full Text Available Paulo E Cabral Filho,1 Maria IA Pereira,1 Heloise P Fernandes,2 Andre A de Thomaz,3 Carlos L Cesar,3 Beate S Santos,4 Maria L Barjas-Castro,2 Adriana Fontes1 1Departamento de Biofísica e Radiobiologia, Universidade Federal de Pernambuco, Recife, Pernambuco, 2Centro de Hematologia e Hemoterapia, Universidade Estadual de Campinas, Instituto Nacional de Ciência e Tecnologia do Sangue, Campinas, São Paulo, 3Departamento de Eletrônica Quântica, Instituto de Física Gleb Wataghin, Universidade Estadual de Campinas, Campinas, São Paulo, 4Departamento de Ciências Farmacêuticas, Universidade Federal de Pernambuco, Recife, PE, Brazil Abstract: New methods of analysis involving semiconductor nanocrystals (quantum dots [QDs] as fluorescent probes have been highlighted in life science. QDs present some advantages when compared to organic dyes, such as size-tunable emission spectra, broad absorption bands, and principally exceptional resistance to photobleaching. Methods applying QDs can be simple, not laborious, and can present high sensibility, allowing biomolecule identification and quantification with high specificity. In this context, the aim of this work was to apply dual-color CdTe QDs to quantify red blood cell (RBC antigen expression on cell surface by flow cytometric analysis. QDs were conjugated to anti-A or anti-B monoclonal antibodies, as well as to the anti-H (Ulex europaeus I lectin, to investigate RBCs of A1, B, A1B, O, A2, and Aweak donors. Bioconjugates were capable of distinguishing the different expressions of RBC antigens, both by labeling efficiency and by flow cytometry histogram profile. Furthermore, results showed that RBCs from Aweak donors present fewer amounts of A antigens and higher amounts of H, when compared to A1 RBCs. In the A group, the amount of A antigens decreased as A1 > A3 > AX = Ael, while H antigens were AX = Ael > A1. Bioconjugates presented stability and remained active for at least 6 months. In conclusion

  20. Structure of ganglioside with CAD blood group antigen activity

    The novel erythrocyte ganglioside which carries the blood group Cad determinant has been isolated, and its structure has been determined. The ganglioside contained Glu:Gal:GalNAc:GlcNAc in a molar ratio of 1.00:1.94:0.93:0.95. The ganglioside binds Helix pomatia lectin and its chromatographic mobility is similar to G/sub D3/. After treatment with β-hexosaminidase (human placenta HexA) the product migrated with sialosylparagloboside (SPG), no longer binds Helix lectin, and binds a human anti-SPG antibody. Treatment of this material with neuraminidase (V. cholera) yielded a product with the mobility of paragloboside that bound monoclonal antibody 1B2. NMR analysis revealed that the terminal GalNAc is linked β1-4 to Gal, and confirms the structure proposed previously: GalNAcβ1-4(NeuAcα2-3)Galβ1-4GlcNAcβ1-3Galβ1-4Glc-Cer. This structure is consistent with the previous demonstration that a compound with the same chromatographic mobility as the Cad ganglioside could be synthesized by enzymatic transfer of GalNAc to sialosylparagloboside

  1. Lymphocyte proliferation to mycobacterial antigens is detectable across a spectrum of HIV-associated tuberculosis

    Bakari Muhammad

    2009-02-01

    Full Text Available Abstract Background Identifying novel TB diagnostics is a major public health priority. We explored the diagnostic characteristics of antimycobacterial lymphocyte proliferation assays (LPA in HIV-infected subjects with latent or active TB. Methods HIV-infected subjects with bacille Calmette Guérin (BCG scars and CD4 counts ≥ 200 cells/mm3 entering a TB booster vaccine trial in Tanzania had baseline in vivo and in vitro immune tests performed: tuberculin skin tests (TST, LPA and five day assays of interferon gamma (IFN-γ release. Assay antigens were early secreted antigenic target 6 (ESAT-6, antigen 85 (Ag85, and Mycobacterium tuberculosis whole cell lysate (WCL. Subjects were screened for active TB at enrollment by history, exam, sputum smear and culture. We compared antimycobacterial immune responses between subjects with and without latent or active TB at enrollment. Results Among 1885 subjects screened, 635 had latent TB and 13 had active TB. Subjects with latent TB were more likely than subjects without TB to have LPA responses to ESAT-6 (13.2% vs. 5.5%, P Conclusion Lymphoproliferative responses to mycobacteria are detectable during HIV-associated active TB, and are less sensitive but more specific than TST. Trial registration ClinicalTrials.gov Identifier NCT00052195.

  2. Regulation of T cell response to leishmania antigens by determinants of histocompatibility leukocyte class I and II molecules

    Bacellar O.

    1998-01-01

    Full Text Available It has been shown that HLA class I molecules play a significant role in the regulation of the proliferation of T cells activated by mitogens and antigens. We evaluated the ability of mAb to a framework determinant of HLA class I molecules to regulate T cell proliferation and interferon gamma (IFN-g production against leishmania, PPD, C. albicans and tetanus toxoid antigens in patients with tegumentary leishmaniasis and healthy subjects. The anti-major histocompatibility complex (MHC mAb (W6/32 suppressed lymphocyte proliferation by 90% in cultures stimulated with aCD3, but the suppression was variable in cultures stimulated with leishmania antigen. This suppression ranged from 30-67% and was observed only in 5 of 11 patients. IFN-g production against leishmania antigen was also suppressed by anti-HLA class I mAb. In 3 patients IFN-g levels were suppressed by more than 60%, while in the other 2 cultures IFN-g levels were 36 and 10% lower than controls. The suppression by HLA class I mAb to the proliferative response in leishmaniasis patients and in healthy controls varied with the antigens and the patients or donors tested. To determine whether the suppression is directed at antigen presenting cells (APCs or at the responding T cells, experiments with antigen-primed non-adherent cells, separately incubated with W6/32, were performed. Suppression of proliferation was only observed when the W6/32 mAb was added in the presence of T cells. These data provide evidence that a mAb directed at HLA class I framework determinants can suppress proliferation and cytokine secretion in response to several antigens.

  3. Reevaluation of the 22-1-1 antibody and its putative antigen, EBAG9/RCAS1, as a tumor marker

    Tumor-associated antigens are appreciated as diagnostic markers, but they have also prompted tremendous efforts to develop tumor-specific immunotherapy. A previously cloned tumor-associated antigen, EBAG9, was initially defined by reactivity with the monoclonal antibody 22-1-1. Functionally, the EBAG9-encoded gene-product was believed to induce apoptosis in activated immune cells. However, using a cell-biological approach we identified EBAG9 as a Golgi-resident modulator of O-linked glycan expression, the latter product was then recognized by the 22-1-1 antibody. Secondly, EBAG9 expression was found physiologically in all murine tissues examined. This raised the question if EBAG9 is tumor-specific and mediates apoptosis itself or through O-linked glycans generated, among them the cognate 22-1-1 antigen Tn. We have used immunohistochemistry to detect the expression of 22-1-1 and EBAG9 in various tissues. Correlation between expression of both antigens in cell lines was analysed by immunoblot and flow cytometry. Apoptosis was studied by using flow cytometry and Caspase-Glo™ 3/7 assay kit. Cellular distribution of EBAG9 was analysed by electron and confocal microscopy. Here, we compared expression of the 22-1-1 and EBAG9-defined antigens in normal and neoplastic tissues in situ. In contrast to 22-1-1 staining, EBAG9 is a ubiquitously expressed antigen in all normal and cancerous tissues. Functional studies on the role of 22-1-1 reactive material did not support any evidence for apoptosis induction. Employing electron and confocal microscopy, a refined subcellular localization of EBAG9 at the Golgi was obtained. We suggest that the estrogen-inducible EBAG9 gene-product and the 22-1-1 defined antigen are structurally and functionally separate antigens

  4. Formaldehyde scavengers function as novel antigen retrieval agents

    Craig T. Vollert; Moree, Wilna J; Steven Gregory; Bark, Steven J.; Eriksen, Jason L.

    2015-01-01

    Antigen retrieval agents improve the detection of formaldehyde-fixed proteins, but how they work is not well understood. We demonstrate that formaldehyde scavenging represents a key characteristic associated with effective antigen retrieval; under controlled temperature and pH conditions, scavenging improves the typical antigen retrieval process through reversal of formaldehyde-protein adduct formation. This approach provides a rational framework for the identification and development of more...

  5. Characterization of Ewing sarcoma associated cancer/testis antigens

    Mahlendorf, Dorothea E.; Staege, Martin Sebastian

    2013-01-01

    The prognosis of patients suffering from tumors of the Ewing family (EFT) is still poor. Immunotherapy strategies are pursued and EFT-specific antigens have to be identified as targets for cytotoxic T-lymphocytes (CTL). Due to the lack of expression of cancer/testis antigens (CTA) in normal tissues, these antigens are partially able to induce immune responses in cancer patients. Therefore, they are promising targets for immunotherapy. EFT are characterized by chromosomal rearrangements involv...

  6. T-cell recognition of a cross-reactive antigen(s) in erythrocyte stages of Plasmodium falciparum and Plasmodium yoelii: inhibition of parasitemia by this antigen(s).

    Lucas, B.; Engels, A; Camus, D; Haque, A.

    1993-01-01

    In the current study, we investigated the presence of a cross-reactive antigen(s) in the erythrocyte stage from Plasmodium yoelii (265 BY strain) and Plasmodium falciparum through recognition by T cells primed in vivo with antigens from each of these parasites. BALB/c mice are naturally resistant to P. falciparum but are susceptible to P. yoelii infection. Mice that had recovered from P. yoelii primary infection became resistant to a second infection. A higher in vitro proliferative response ...

  7. Pneumocystis carinii antigen detection in rat serum and lung lavage.

    McNabb, S J; Graves, D C; Kosanke, S.D.; Moyer, M J; Ivey, M H

    1988-01-01

    We developed a modified double-antibody sandwich enzyme-linked immunosorbent assay (ELISA) that detected relatively low concentrations of known Pneumocystis carinii antigen added to buffer or rat sera. Artificial immunization-derived polyclonal rabbit anti-P. carinii antibody was used on the solid phase to capture the antigen. Infection-derived (after P. carinii pneumonia) polyclonal rat anti-P. carinii antibody or a mixture of five murine monoclonal antibodies was used as the antigen detecto...

  8. The role of antigenically different virus neuraminidases as structures implicated in receptor-binding processes.

    Coimbra, M V; Luiz, M O; Cabral, M C; Couceiro, J N

    1995-06-01

    Influenza A viruses exhibit segmented nucleic acid coding for eight different proteins, two of them as glycoproteins exposed on their lipoprotein envelopes, hemagglutinin (HA) and neuraminidase (NA). Hemagglutinin exhibits receptor-binding activity while neuraminidase develops sialidase cleavage activity which acts on cell receptors. Influenza A strains responsible for human, avian, equine and porcine respiratory infections all over the world present antigenically different hemagglutinin (H1 to H14) and neuraminidase (N1 to N9) structures on their surface. The objective of the present investigation was to study the role of N2, N8, and N9, antigenically diverse neuraminidase structures of human (N2) and animal (N8 and N9) influenza viruses, in the receptor-binding process. Receptor-binding activity of N2 and N8 was analyzed by crossed tests using H3N2 and H3N8 antisera and the hemagglutination inhibition test as a model. Hemagglutinating activity of antigenically different N2 and N8 structures was demonstrable and was inhibited by homologous antisera (N2-H3N2, N8-H3N8) but not by heterologous antisera (N2-H3N8,N8-H3N2). This previously demonstrated N9 hemagglutinating activity was analyzed for receptor-binding specificity using hemagglutination tests and NeuAc alpha2,3Gal and NeuAc alpha2,6Gal derivatized erythrocytes. This highly purified N9 strain was obtained from a virus strain isolated from terns by Dr. Peter Colman (CSIRO Division of Biomolecular Engineering, Parkville, Victoria, Australia). It exhibited receptor-binding specificity for NeuAc alpha2,3Gal sequences, a property similar to that observed in hemagglutinins from avian strains. These results indicate the importance of antigenically different neuraminidase structures as alternative agents for developing receptor-binding activity.(ABSTRACT TRUNCATED AT 250 WORDS) PMID:8547843

  9. Cancer-germline antigen vaccines and epigenetic enhancers

    Gjerstorff, Morten Frier; Burns, Jorge; Ditzel, Henrik Jorn

    2010-01-01

    can be achieved using epigenetic modifiers. AREAS COVERED IN THIS REVIEW: We provide an overview of the potential of CG antigens as targets for cancer immunotherapy, including advantages and disadvantages. We also discuss the current state of development of CG antigen vaccines, and the potential...... synergistic effect of combining CG antigen immunotherapeutic strategies with epigenetic modifiers. WHAT THE READER WILL GAIN: The reader will gain an overview of the past, present and future role of CG antigens in cancer immunotherapy. TAKE HOME MESSAGE: Chemoimmunotherapy using epigenetic drugs and CG...

  10. V-antigen homologs in pathogenic gram-negative bacteria.

    Sawa, Teiji; Katoh, Hideya; Yasumoto, Hiroaki

    2014-05-01

    Gram-negative bacteria cause many types of infections in animals from fish and shrimps to humans. Bacteria use Type III secretion systems (TTSSs) to translocate their toxins directly into eukaryotic cells. The V-antigen is a multifunctional protein required for the TTSS in Yersinia and Pseudomonas aeruginosa. V-antigen vaccines and anti-V-antigen antisera confer protection against Yersinia or P. aeruginosa infections in animal models. The V-antigen forms a pentameric cap structure at the tip of the Type III secretory needle; this structure, which has evolved from the bacterial flagellar cap structure, is indispensable for toxin translocation. Various pathogenic gram-negative bacteria such as Photorhabdus luminescens, Vibrio spp., and Aeromonas spp. encode homologs of the V-antigen. Because the V-antigens of pathogenic gram-negative bacteria play a key role in toxin translocation, they are potential therapeutic targets for combatting bacterial virulence. In the USA and Europe, these vaccines and specific antibodies against V-antigens are in clinical trials investigating the treatment of Yersinia or P. aeruginosa infections. Pathogenic gram-negative bacteria are of great interest because of their ability to infect fish and shrimp farms, their potential for exploitation in biological terrorism attacks, and their ability to cause opportunistic infections in humans. Thus, elucidation of the roles of the V-antigen in the TTSS and mechanisms by which these functions can be blocked is critical to facilitating the development of improved anti-V-antigen strategies. PMID:24641673

  11. ANTIGENICITY OF COW'S MILK PROTEINS IN TWO ANIMAL MODELS

    T.R. Neyestani; M. Djalali M. I'ezeshki

    2000-01-01

    Antigenicity of proteins found in cow's milk is age dependent. This is primarily due to infants possessing a more permeable intestinal wall than that in adults. Thus infants may acquire cow's milk allergy during their first year of life. While milk antigen specific IgE may cause allergy in susceptible subjects, there is some evidence indicating that milk antigen specific IgG may play some role in chronic disease development. The puropose of this study was to determine the antigenicity of cow'...

  12. Antigenic composition of single nano-sized extracellular blood vesicles.

    Arakelyan, Anush; Ivanova, Oxana; Vasilieva, Elena; Grivel, Jean-Charles; Margolis, Leonid

    2015-04-01

    Extracellular vesicles (EVs) are important in normal physiology and are altered in various pathologies. EVs produced by different cells are antigenically different. Since the majority of EVs are too small for routine flow cytometry, EV composition is studied predominantly in bulk, thus not addressing their antigenic heterogeneity. Here, we describe a nanoparticle-based technique for analyzing antigens on single nano-sized EVs. The technique consists of immuno-capturing of EVs with 15-nm magnetic nanoparticles, staining captured EVs with antibodies against their antigens, and separating them from unbound EVs and free antibodies in a magnetic field, followed by flow analysis. This technique allows us to characterize EVs populations according to their antigenic distribution, including minor EV fractions. We demonstrated that the individual blood EVs carry different sets of antigens, none being ubiquitous, and quantified their distribution. The physiological significance of antigenically different EVs and their correlation with different pathologies can now be directly addressed. From the clinical editor: This study reports a nanoparticle-based technique for analyzing antigens on single nano-sized extracellular vehicles (EV). The technique consists of immuno-capturing of EVs with 15-nm magnetic nanoparticles, followed by staining the captured EVs with antibodies and separating them via a magnetic field, followed by flow analysis. This technique enables studies of antigenic properties of individual EVs that conventionally can only be studied in bulk. PMID:25481806

  13. Antigen-Specific versus Non-Antigen-Specific Immunoadsorption in ABO-Incompatible Renal Transplantation.

    Gerold Thölking

    Full Text Available ABO-incompatible (ABOi renal transplantation (RTx from living donors is an established procedure to expand the donor pool for patients with end stage renal disease. Immunoadsorption (IA is a standard procedure for the removal of preformed antibodies against the allograft. In this study, antigen-specific and non-antigen-specific IA in ABOi RTx were compared.10 patients underwent antigen-specific IA (Glycosorb group and 13 patients non-antigen-specific IA (Immunosorba group. The effects of both procedures regarding antibody reduction, number of treatments, complications, costs, as well as the allograft function and patient survival were compared between both groups.Although the IgG levels were reduced equally by both procedures (p=0.82, the reduction of the IgM level was more effective in the Glycosorb group (p=0.0172. Patients in both groups required a median number of 6 IA before ABOi RTx. Allograft function at one year after AB0i RTx was similar in both groups (estimated glomerular filtration rate: 66 vs. 64 ml/min/1.73m² respectively, with a death-censored graft survival of 90.0% and 92.3% respectively. Complication rates did not differ between procedures. Due to the reuse of non-antigen-specific Immunosorba columns, costs were considerably lower in this group; however, the use of the Immunosorba-based IA was less time-efficient.Considering upcoming alternatives as simultaneous performance of dialysis and IA or a possible reuse of Glycosorb columns, this might become less relevant in the future.

  14. Detection of peste des petits ruminants virus antigen using immunofiltration and antigen-competition ELISA methods.

    Raj, G Dhinakar; Rajanathan, T M C; Kumar, C Senthil; Ramathilagam, G; Hiremath, Geetha; Shaila, M S

    2008-06-22

    Peste des petits ruminants (PPR) is one of the most economically important diseases affecting sheep and goats in India. An immunofiltration-based test has been developed using either mono-specific serum/monoclonal antibodies (mAb) prepared against a recombinant truncated nucleocapsid protein of rinderpest virus (RPV) cross-reactive with PPR virus. This method consists of coating ocular swab eluate from suspected animals onto a nitrocellulose membrane housed in a plastic module, which is allowed to react with suitable dilutions of a mAb or a mono-specific polyclonal antibody. The antigen-antibody complex formed on the membrane is then detected by protein A-colloidal gold conjugate, which forms a pink colour. In the immunofiltration test, concordant results were obtained using either PPRV mAb or mono-specific serum. Another test, an antigen-competition ELISA which relies on the competition between plate-coated recombinant truncated 'N' protein of RPV and the PPRV 'N' protein present in ocular swab eluates (sample) for binding to the mono-specific antibody against N protein of RPV (in liquid phase) was developed. The cut-off value for this test was established using reverse transcription polymerase chain reaction (RT-PCR) positive and negative oculo-nasal swab samples. Linear correlation between percent inhibition (PI) values in antigen-competition ELISA and virus infectivity titres was 0.992. Comparison of the immunofiltration test with the antigen-competition ELISA yielded a sensitivity of 80% and specificity of 100%. These two tests can serve as a screening (immunofiltration) and confirmatory (antigen-competition ELISA) test, respectively, in the diagnosis of PPR in sheep or goats. PMID:18182256

  15. Antigen dose escalation study of a VEGF-based therapeutic cancer vaccine in non human primates.

    Morera, Yanelys; Bequet-Romero, Mónica; Ayala, Marta; Pérez, Pedro Puente; Castro, Jorge; Sánchez, Javier; Alba, José Suárez; Ancízar, Julio; Cosme, Karelia; Gavilondo, Jorge V

    2012-01-01

    CIGB-247 is a cancer therapeutic, based on recombinant modified human vascular endothelial growth factor (VEGF) as antigen, in combination with the oil free adjuvant VSSP (very small sized proteoliposomes of Neisseria meningitidis outer membrane). Our previous experimental studies in mice with CIGB-247 have shown that the vaccine has both anti-tumoral and anti-metastatic activity, and produces both antibodies that block VEGF-VEGF receptor interaction, and a specific T-cell cytotoxic response against tumor cells. CIGB-247, with an antigen dose of 100 μg, has been characterized by an excellent safety profile in mice, rats, rabbits, and non human primates. In this article we extend the immunogenicity and safety studies of CIGB-247 in non human primates, scaling the antigen dose from 100 μg to 200 and 400 μg/vaccination. Our results indicate that such dose escalation did not affect animal behavior, clinical status, and blood parameters and biochemistry. Also, vaccination did not interfere with skin deep skin wound healing. Anti-VEGF IgG antibodies and specific T-cell mediated responses were documented at all three studied doses. Antigen dose apparently did not determine differences in maximum antibody titer during the 8 weekly immunization induction phase, or the subsequent increase in antibodies seen for monthly boosters delivered afterwards. Higher antigen doses had a positive influence in antibody titer maintenance, after cessation of immunizations. Boosters were important to achieve maximum antibody VEGF blocking activity, and specific T-cell responses in all individuals. Purified IgG from CIGB-247 immunized monkey sera was able to impair proliferation and formation of capillary-like structures in Matrigel, for HMEC cells in culture. Altogether, these results support the further clinical development of the CIGB-247 therapeutic cancer vaccine, and inform on the potential mechanisms involved in its effect. PMID:22075086

  16. Cellular gene expression induced by parasite antigens and allergens in neonates from parasite-infected mothers.

    Soboslay, Peter T; Orlikowsky, Thorsten; Huang, Xiangsheng; Gille, Christian; Spring, Bärbel; Kocherscheidt, Lars; Agossou, Abram; Banla, Meba; Bonin, Michael; Köhler, Carsten

    2016-05-01

    Prenatal exposure to parasite antigens or allergens will influence the profile and strength of postnatal immune responses, such contact may tolerize and increase susceptibility to future infections or sensitize to environmental allergens. Exposure in utero to parasite antigens will distinctly alter cellular gene expression in newborns. Gene microarrays were applied to study gene expression in umbilical cord blood cell (UCBC) from parasite-exposed (Para-POS) and non-exposed (Para-NEG) neonates. UCBC were activated with antigens of helminth (Onchocerca volvulus), amoeba (Entamoeba histolytica) or allergens of mite (Dermatophagoides farinae). When UCBC from Para-POS and Para-NEG newborns were exposed to helminth antigens or allergens consistent differences occurred in the expression of genes encoding for MHC class I and II alleles, signal transducers of activation and transcription (STATs), cytokines, chemokines, immunoglobulin heavy and light chains, and molecules associated with immune regulation (SOCS, TLR, TGF), inflammation (TNF, CCR) and apoptosis (CASP). Expression of genes associated with innate immune responses were enhanced in Para-NEG, while in Para-POS, the expression of MHC class II and STAT genes was reduced. Within functional gene networks for cellular growth, proliferation and immune responses, Para-NEG neonates presented with significantly higher expression values than Para-POS. In Para-NEG newborns, the gene cluster and pathway analyses suggested that gene expression profiles may predispose for the development of immunological, hematological and dermatological disorders upon postnatal helminth parasite infection or allergen exposure. Thus, prenatal parasite contact will sensitize without generating aberrant inflammatory immune responses, and increased pro-inflammatory but decreased regulatory gene expression profiles will be present in those neonates lacking prenatal parasite antigen encounter. PMID:27062712

  17. Antigen-Specific CD4+ T Cells Recognize Epitopes of Protective Antigen following Vaccination with an Anthrax Vaccine

    Laughlin, Elsa M.; Miller, Joseph D.; James, Eddie; Fillos, Dimitri; Ibegbu, Chris C.; Mittler, Robert S.; Akondy, Rama; Kwok, William; Ahmed, Rafi; Nepom, Gerald,

    2007-01-01

    Detection of antigen-specific CD4+ T cells is facilitated by the use of fluorescently labeled soluble peptide-major histocompatibility complex (MHC) multimers which mirror the antigen specificity of T-cell receptor recognition. We have used soluble peptide-MHC class II tetramers containing peptides from the protective antigen (PA) of Bacillus anthracis to detect circulating T cells in peripheral blood of subjects vaccinated with an anthrax vaccine. PA-specific HLA class II-restricted T lympho...

  18. Antineutrophil antibodies associated with ulcerative colitis interact with the antigen(s) during the process of apoptosis

    Mallolas, J; Esteve, M; Rius, E; Cabre, E; Gassull, M

    2000-01-01

    BACKGROUND—Cell death by apoptosis seems to be an important mechanism for translocation to the cell surface of a variety of intracellular components capable of inducing autoantibody production.
AIMS—To identify the cellular location of antigen (Ag)-antineutrophil cytoplasmic antibodies (ANCA) in non-apoptotic human neutrophils, and to assess if ANCA associated with ulcerative colitis reacts with neutrophil antigen(s) during neutrophil apoptosis. The cellular distribution of Ag-ANCA in apoptot...

  19. Presensitization to Ascaris antigens promotes induction of mite-specific IgE upon mite antigen inhalation in mice

    Mayu Suzuki; Mutsuko Hara; Saori Ichikawa; Seiji Kamijo; Takuya Nakazawa; Hideki Hatanaka; Kazuo Akiyama; Hideoki Ogawa; Ko Okumura; Toshiro Takai

    2016-01-01

    Background: Patients with house dust mite (HDM) allergy or Ascariasis produce serum IgE specific to the antigens of HDM or nematode Ascaris, respectively. Although human IgE cross-reactivity has been reported between HDM and Ascaris antigens, it remains unclear whether it contributes to the pathogenesis of allergic diseases. We herein investigated the induction of cross-reactive antibodies and T cells in mice and effects of airway exposure to HDM antigens after preimmunization with Ascaris an...

  20. Lymphocyte Proliferation Response to S Antigen in Patients with Uveitis and Optic Neuritis

    PeixianRen; XiuzhenYan

    1995-01-01

    Purpose:To evaluate the autoimmunity which may play a major role in the etiolo-gy of certain forms of uveitis and optic neuritis.Methods:lymphocyte proliferation response to retinal soluble antigen in vitro by gy of certain forms of uveitis and optic neuritis.Methods:Lymphocyte proliferation response toretinal soluble antigen in vitro by incoperation3H-thymidine withDNA was tested in 115patients with anterior u-veitis,posterior/pan-uveitis,optic neuritis,and 50volunteers with unrelated diseases such as congenital ptosis,strabismus,or completely healthy persons as control.Results:The positive rate of lymphocyte stimulation was34%(18/53)in anteri-or uveitis,41.5%(17/41)in posterior/pan-uveitis,and57.1%(12/21)in optic euritis,The results in the experimental groups were significantly different from those of the control group(x2=14.76,P<0.05,x2=19.14P<0.005,x2=26.38,P<0.005,respectively).Conclusion:The autoimmunity plays a role in the patogenesis in certain forms of uveitis and optic neuritis,Such immune responses may be secondary to the expo-sition or release of retinal antigens by various causes,leading to activation or augmentation of meager or low-affinity S antigen specific lymphocytes which may preexist in the circulation and starting the pathogenic autoimmune process.Eye Science 1995;11:120-123.