Scripts for TRUMP data analyses. Part II (HLA-related data): statistical analyses specific for hematopoietic stem cell transplantation.

Science.gov (United States)

Kanda, Junya

2016-01-01

The Transplant Registry Unified Management Program (TRUMP) made it possible for members of the Japan Society for Hematopoietic Cell Transplantation (JSHCT) to analyze large sets of national registry data on autologous and allogeneic hematopoietic stem cell transplantation. However, as the processes used to collect transplantation information are complex and differed over time, the background of these processes should be understood when using TRUMP data. Previously, information on the HLA locus of patients and donors had been collected using a questionnaire-based free-description method, resulting in some input errors. To correct minor but significant errors and provide accurate HLA matching data, the use of a Stata or EZR/R script offered by the JSHCT is strongly recommended when analyzing HLA data in the TRUMP dataset. The HLA mismatch direction, mismatch counting method, and different impacts of HLA mismatches by stem cell source are other important factors in the analysis of HLA data. Additionally, researchers should understand the statistical analyses specific for hematopoietic stem cell transplantation, such as competing risk, landmark analysis, and time-dependent analysis, to correctly analyze transplant data. The data center of the JSHCT can be contacted if statistical assistance is required.

Impaired cell surface expression of HLA-B antigens on mesenchymal stem cells and muscle cell progenitors

DEFF Research Database (Denmark)

Isa, Adiba; Nehlin, Jan; Sabir, Hardee Jawad

2010-01-01

HLA class-I expression is weak in embryonic stem cells but increases rapidly during lineage progression. It is unknown whether all three classical HLA class-I antigens follow the same developmental program. In the present study, we investigated allele-specific expression of HLA-A, -B, and -C...... at the mRNA and protein levels on human mesenchymal stem cells from bone marrow and adipose tissue as well as striated muscle satellite cells and lymphocytes. Using multicolour flow cytometry, we found high cell surface expression of HLA-A on all stem cells and PBMC examined. Surprisingly, HLA-B was either...... undetectable or very weakly expressed on all stem cells protecting them from complement-dependent cytotoxicity (CDC) using relevant human anti-B and anti-Cw sera. IFNgamma stimulation for 48-72 h was required to induce full HLA-B protein expression. Quantitative real-time RT-PCR showed that IFNgamma induced...

A common minimal motif for the ligands of HLA-B*27 class I molecules.

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Barriga, Alejandro; Lorente, Elena; Johnstone, Carolina; Mir, Carmen; del Val, Margarita; López, Daniel

2014-01-01

CD8(+) T cells identify and kill infected cells through the specific recognition of short viral antigens bound to human major histocompatibility complex (HLA) class I molecules. The colossal number of polymorphisms in HLA molecules makes it essential to characterize the antigen-presenting properties common to large HLA families or supertypes. In this context, the HLA-B*27 family comprising at least 100 different alleles, some of them widely distributed in the human population, is involved in the cellular immune response against pathogens and also associated to autoimmune spondyloarthritis being thus a relevant target of study. To this end, HLA binding assays performed using nine HLA-B*2705-restricted ligands endogenously processed and presented in virus-infected cells revealed a common minimal peptide motif for efficient binding to the HLA-B*27 family. The motif was independently confirmed using four unrelated peptides. This experimental approach, which could be easily transferred to other HLA class I families and supertypes, has implications for the validation of new bioinformatics tools in the functional clustering of HLA molecules, for the identification of antiviral cytotoxic T lymphocyte responses, and for future vaccine development.

A common minimal motif for the ligands of HLA-B*27 class I molecules.

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Alejandro Barriga

Full Text Available CD8(+ T cells identify and kill infected cells through the specific recognition of short viral antigens bound to human major histocompatibility complex (HLA class I molecules. The colossal number of polymorphisms in HLA molecules makes it essential to characterize the antigen-presenting properties common to large HLA families or supertypes. In this context, the HLA-B*27 family comprising at least 100 different alleles, some of them widely distributed in the human population, is involved in the cellular immune response against pathogens and also associated to autoimmune spondyloarthritis being thus a relevant target of study. To this end, HLA binding assays performed using nine HLA-B*2705-restricted ligands endogenously processed and presented in virus-infected cells revealed a common minimal peptide motif for efficient binding to the HLA-B*27 family. The motif was independently confirmed using four unrelated peptides. This experimental approach, which could be easily transferred to other HLA class I families and supertypes, has implications for the validation of new bioinformatics tools in the functional clustering of HLA molecules, for the identification of antiviral cytotoxic T lymphocyte responses, and for future vaccine development.

Role of HLA-G1 in trophoblast cell proliferation, adhesion and invasion

International Nuclear Information System (INIS)

Jiang, Feng; Zhao, Hongxi; Wang, Li; Guo, Xinyu; Wang, Xiaohong; Yin, Guowu; Hu, Yunsheng; Li, Yi; Yao, Yuanqing

2015-01-01

Trophoblast cells are important in embryo implantation and fetomaternal tolerance. HLA-G is specifically expressed at the maternal–fetal interface and is a regulator in pregnancy. The aim of the present study was to detect the effect of HLA-G1 on trophoblast cell proliferation, adhesion, and invasion. Human trophoblast cell lines (JAR and HTR-8/SVneo cells) were infected with HLA-G1-expressing lentivirus. After infection, HLA-G1 expression of the cells was detected by western blotting. Cell proliferation was detected by the BrdU assay. The cell cycle and apoptosis of JAR and HTR-8/SVneo cells was measured by flow cytometry (FCM). The invasion of the cells under different conditions was detected by the transwell invasion chamber assay. HLA-G1 didn't show any significant influence on the proliferation, apoptosis, adhesion, and invasion of trophocytes in normal culture conditions. However, HLA-G1 inhibited JAR and HTR-8/SVneo cells invasion induced by hepatocyte growth factor (HGF) under normal oxygen conditions. In conditions of hypoxia, HLA-G1 couldn't inhibit the induction of cell invasion by HGF. HLA-G1 is not an independent factor for regulating the trophocytes. It may play an indirect role in embryo implantation and formation of the placenta. - Highlights: • HLA-G1 could not influence trophocytes under normal conditions. • HLA-G1 inhibited cell invasion induced by HGF under normal oxygen condition. • HLA-G1 could not influence cell invasion under hypoxia conditions

Role of HLA-G1 in trophoblast cell proliferation, adhesion and invasion

Energy Technology Data Exchange (ETDEWEB)

Jiang, Feng, E-mail: jiangfeng1161@163.com [Department of Gynecology and Obstetrics, Tangdu Hospital, The Fourth Military Medical University, 569 Xinsi Road, Baqiao District, Xi' an 710038 (China); Zhao, Hongxi [Department of Gynecology and Obstetrics, Tangdu Hospital, The Fourth Military Medical University, 569 Xinsi Road, Baqiao District, Xi' an 710038 (China); Wang, Li [Department of Gynecology and Obstetrics, The Chinese PLA General Hospital, 28 Fuxing Road, Haidian District, Beijing 100853 (China); Guo, Xinyu [Assisted Reproductive Center, General Hospital of Guangzhou Military Command, Guangzhou 510010 (China); Wang, Xiaohong; Yin, Guowu [Department of Gynecology and Obstetrics, Tangdu Hospital, The Fourth Military Medical University, 569 Xinsi Road, Baqiao District, Xi' an 710038 (China); Hu, Yunsheng [Department of Orthopedics, Tangdu Hospital, The Fourth Military Medical University, Xi' an 710038 (China); Li, Yi [Department of Gynecology and Obstetrics, Tangdu Hospital, The Fourth Military Medical University, 569 Xinsi Road, Baqiao District, Xi' an 710038 (China); Yao, Yuanqing, E-mail: yuanqingyaoxa@163.com [Department of Gynecology and Obstetrics, The Chinese PLA General Hospital, 28 Fuxing Road, Haidian District, Beijing 100853 (China)

2015-02-27

Trophoblast cells are important in embryo implantation and fetomaternal tolerance. HLA-G is specifically expressed at the maternal–fetal interface and is a regulator in pregnancy. The aim of the present study was to detect the effect of HLA-G1 on trophoblast cell proliferation, adhesion, and invasion. Human trophoblast cell lines (JAR and HTR-8/SVneo cells) were infected with HLA-G1-expressing lentivirus. After infection, HLA-G1 expression of the cells was detected by western blotting. Cell proliferation was detected by the BrdU assay. The cell cycle and apoptosis of JAR and HTR-8/SVneo cells was measured by flow cytometry (FCM). The invasion of the cells under different conditions was detected by the transwell invasion chamber assay. HLA-G1 didn't show any significant influence on the proliferation, apoptosis, adhesion, and invasion of trophocytes in normal culture conditions. However, HLA-G1 inhibited JAR and HTR-8/SVneo cells invasion induced by hepatocyte growth factor (HGF) under normal oxygen conditions. In conditions of hypoxia, HLA-G1 couldn't inhibit the induction of cell invasion by HGF. HLA-G1 is not an independent factor for regulating the trophocytes. It may play an indirect role in embryo implantation and formation of the placenta. - Highlights: • HLA-G1 could not influence trophocytes under normal conditions. • HLA-G1 inhibited cell invasion induced by HGF under normal oxygen condition. • HLA-G1 could not influence cell invasion under hypoxia conditions.

HLA-E-expressing pluripotent stem cells escape allogeneic responses and lysis by NK cells.

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Gornalusse, Germán G; Hirata, Roli K; Funk, Sarah E; Riolobos, Laura; Lopes, Vanda S; Manske, Gabriel; Prunkard, Donna; Colunga, Aric G; Hanafi, Laïla-Aïcha; Clegg, Dennis O; Turtle, Cameron; Russell, David W

2017-08-01

Polymorphisms in the human leukocyte antigen (HLA) class I genes can cause the rejection of pluripotent stem cell (PSC)-derived products in allogeneic recipients. Disruption of the Beta-2 Microglobulin (B2M) gene eliminates surface expression of all class I molecules, but leaves the cells vulnerable to lysis by natural killer (NK) cells. Here we show that this 'missing-self' response can be prevented by forced expression of minimally polymorphic HLA-E molecules. We use adeno-associated virus (AAV)-mediated gene editing to knock in HLA-E genes at the B2M locus in human PSCs in a manner that confers inducible, regulated, surface expression of HLA-E single-chain dimers (fused to B2M) or trimers (fused to B2M and a peptide antigen), without surface expression of HLA-A, B or C. These HLA-engineered PSCs and their differentiated derivatives are not recognized as allogeneic by CD8 + T cells, do not bind anti-HLA antibodies and are resistant to NK-mediated lysis. Our approach provides a potential source of universal donor cells for applications where the differentiated derivatives lack HLA class II expression.

HLA-E-expressing pluripotent stem cells escape allogeneic responses and lysis by NK cells

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Gornalusse, Germán G.; Hirata, Roli K.; Funk, Sarah; Riolobos, Laura; Lopes, Vanda S.; Manske, Gabriel; Prunkard, Donna; Colunga, Aric G.; Hanafi, Laïla-Aïcha; Clegg, Dennis O.; Turtle, Cameron; Russell, David W.

2017-01-01

Polymorphisms in the human leukocyte antigen (HLA) class I genes can cause the rejection of pluripotent stem cell (PSC)-derived products in allogeneic recipients. Disruption of the Beta-2 Microglobulin (B2M) gene eliminates surface expression of all class I molecules, but leaves the cells vulnerable to lysis by natural killer (NK) cells. Here we show that this ‘missing self’ response can be prevented by forced expression of minimally polymorphic HLA-E molecules. We use adeno-associated virus (AAV)-mediated gene editing to knock in HLA-E genes at the B2M locus in human PSCs in a manner that confers inducible, regulated, surface expression of HLA-E single-chain dimers (fused to B2M) or trimers (fused to B2M and a peptide antigen), without surface expression of HLA-A, B or C. These HLA-engineered PSCs and their differentiated derivatives are not recognized as allogeneic by CD8+ T cells, do not bind anti-HLA antibodies, and are resistant to NK-mediated lysis. Our approach provides a potential source of universal donor cells for applications where the differentiated derivatives lack HLA class II expression. PMID:28504668

Natural HLA-B*2705 Protein Ligands with Glutamine as Anchor Motif

Science.gov (United States)

Infantes, Susana; Lorente, Elena; Barnea, Eilon; Beer, Ilan; Barriga, Alejandro; Lasala, Fátima; Jiménez, Mercedes; Admon, Arie; López, Daniel

2013-01-01

The presentation of short viral peptide antigens by human leukocyte antigen (HLA) class I molecules on cell surfaces is a key step in the activation of cytotoxic T lymphocytes, which mediate the killing of pathogen-infected cells or initiate autoimmune tissue damage. HLA-B27 is a well known class I molecule that is used to study both facets of the cellular immune response. Using mass spectrometry analysis of complex HLA-bound peptide pools isolated from large amounts of HLA-B*2705+ cells, we identified 200 naturally processed HLA-B*2705 ligands. Our analyses revealed that a change in the position (P) 2 anchor motif was detected in the 3% of HLA-B*2705 ligands identified. B*2705 class I molecules were able to bind these six GlnP2 peptides, which showed significant homology to pathogenic bacterial sequences, with a broad range of affinities. One of these ligands was able to bind with distinct conformations to HLA-B27 subtypes differentially associated with ankylosing spondylitis. These conformational differences could be sufficient to initiate autoimmune damage in patients with ankylosing spondylitis-associated subtypes. Therefore, these kinds of peptides (short, with GlnP2, and similar low affinity to all HLA-B27 subtypes tested but with unlike conformations in differentially ankylosing spondylitis-associated subtypes) must not be excluded from future researches involving potential arthritogenic peptides. PMID:23430249

Cytotoxic T lymphocyte recognition of HLA-A/B antigens introduced into EL4 cells by cell-liposome fusion.

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Engelhard, V H; Powers, G A; Moore, L C; Holterman, M J; Correa-Freire, M C

1984-01-01

HLA-A2 and -B7 antigens were introduced into EL4 (H-2b) cells by cell-liposome fusion and were used as targets or stimulators for cytotoxic T lymphocytes (CTL) generated in C57B1/6 (H-2b) mice. It was found that such EL4-HLA cells were not recognized by CTL that had been raised against either a human cell line bearing these HLA antigens or the purified HLA-A2 and -B7 antigens reconstituted into liposomes. In addition, EL4-HLA cells were not capable of inducing CTL that could recognize a human cell line bearing HLA-A2 and -B7 antigens. Instead, EL4-HLA cells induced CTL that specifically lysed EL4-HLA cells and not human cells expressing HLA-A2 and -B7. CTL recognition required the presence of HLA antigens on the EL4 cell surface and was inhibited by antibodies against either H-2b or HLA-A/B. Monoclonal antibody binding studies showed that the expected polymorphic determinants of the HLA-A2 and -B7 antigens were still present on EL4-HLA cells. However, the specificity of CTL or their precursors that are capable of recognizing HLA-A2 or -B7 was altered after these antigens became associated with the EL4 surface. Possible explanations for these results are discussed.

HLA class Ib in pregnancy and pregnancy-related disorders.

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Persson, Gry; Melsted, Wenna Nascimento; Nilsson, Line Lynge; Hviid, Thomas Vauvert F

2017-08-01

The HLA class Ib genes, HLA-E, HLA-F, and HLA-G, were discovered long after the classical HLA class Ia genes. The elucidation of their functions had a modest beginning. However, their basic functions and involvement in pathophysiology and a range of diseases are now emerging. Although results from a range of studies support the functional roles for the HLA class Ib molecules in adult life, especially HLA-G and HLA-F have most intensively been, and were also primarily, studied in relation to reproduction and pregnancy. The expression of HLA class Ib proteins at the feto-maternal interface in the placenta seems to be important for the maternal acceptance of the semi-allogenic fetus. In contrast to the functions of HLA class Ia, HLA-G possesses immune-modulatory and tolerogenic functions. Here, we review an accumulating amount of data describing the functions of HLA class Ib molecules in relation to fertility, reproduction, and pregnancy, and a possible role for these molecules in certain pregnancy complications, such as implantation failure, recurrent spontaneous abortions, and pre-eclampsia. The results from different kinds of studies point toward a role for HLA class Ib, especially HLA-G, throughout the reproductive cycle from conception to the birth weight of the child.

Preimplantation HLA typing for stem cell transplantation treatment of hemoglobinopathies

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Anver Kuliev

2014-09-01

Full Text Available Preimplantation genetic diagnosis (PGD for HLA typing is steadily becoming an option for at risk couples with thalassemic children, requiring HLA matched bone marrow transplantation treatment. The paper presents the world’s largest PGD experience of 475 cases for over 2 dozens thalassemia mutations, resulting in birth of 132 unaffected children. A total of 146 cases were performed together with preimplantation HLA typing, resulting in detection and transfer of HLA matched unaffected embryos in 83 of them, yielding the birth of 16 HLA matched children, potential donors for their affected siblings. The presented experience of HLA matched stem cell transplantation for thalassemia, following PGD demonstrated a successful hematopoietic reconstitution both for younger and older patients. The data show that PGD is an efficient approach for HLA matched stem cell transplantation treatment for thalassemia.

Antigen Presenting Cells and Stromal Cells Trigger Human Natural Killer Lymphocytes to Autoreactivity: Evidence for the Involvement of Natural Cytotoxicity Receptors (NCR and NKG2D

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Alessandro Poggi

2006-01-01

Full Text Available Human natural killer (NK lymphocytes should not damage autologous cells due to the engagement of inhibitory receptor superfamily (IRS members by HLA-I. Nevertheless, NK cells kill self cells expressing low levels or lacking HLA-I, as it may occur during viral infections (missing-self hypothesis. Herein, we show that human NK cells can be activated upon binding with self antigen presenting cells or stromal cells despite the expression of HLA-I. Indeed, NK cells can kill and produce pro-inflammatory and regulating cytokines as IFN-γ, TNF-α and IL10 during interaction with autologous dendritic cells or bone marrow stromal cells or skin fibroblasts. The killing of antigen presenting and stromal cells is dependent on LFA1/ICAM1 interaction. Further, the natural cytotoxicity receptors (NCR NKp30 and NKp46 are responsible for the delivery of lethal hit to DC, whereas NKG2D activating receptor, the ligand of the MHC-related molecule MIC-A and the UL16 binding protein, is involved in stromal cell killing. These findings indicate that different activating receptors are involved in cell to self cell interaction. Finally, NK cells can revert the veto effect of stromal cells on mixed lymphocyte reaction further supporting the idea that NK cells may alter the interaction between T lymphocytes and microenvironment leading to autoreactivity.

HLA-C incompatibilities in allogeneic unrelated hematopoietic stem cell transplantation

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Jean-Marie eTIERCY

2014-05-01

Full Text Available An increasingly larger fraction of patients with hematological diseases are treated by hematopoietic stem cells transplantation (HSCT from HLA matched unrelated donors. Polymorphism of HLA genes represent a major barrier to HSCT because HLA-A,B,C and DRB1 incompatibilities confer a higher risk of aGVHD and mortality. Although >22 million volunteer HLA-typed donors are available worldwide, still a significant number of patients do not find a highly matched HSC donor. Because of the large haplotypic diversity in HLA-B-C associations, incompatibilities occur most frequently at HLA-C, so that unrelated donors with a single HLA-C mismatch often represent the only possible choice. The ratio of HLA-C-mismatched HSCT over the total number of transplants varies from 15-30%, as determined in 12 multicenter studies. Six multicenter studies involving >1800 patients have reported a 21-43% increase in mortality risk. By using in vitro cellular assays a large heterogeneity in T-cell allorecognition has been observed. Yet the permissiveness of individual HLA-C mismatches remains poorly defined. It could be linked to the position and nature of the mismatched residues on HLA-C molecules, but also to variability in the expression levels of the mismatched alleles. The permissive C*03:03-03:04 mismatch is caracterized by full compatibility at residues 9, 97, 99, 116, 152, 156 and 163 reported to be key positions influencing T-cell allorecognition. With a single difference in these key residues the C*07:01-07:02 mismatch might also be considered by analogy as permissive. High variability of HLA-C expression as determined by quantitative RT-PCR has been observed within individual allotypes and shows some correlation with A-B-C-DRB1 haplotypes. Thus in addition to the position of mismatched amino acid residues, expression level of patient’s mismatched HLA-C allotype might influence T-cell allorecognition, with patient's low expression-C alleles representing possible

Identification of NY-BR-1-specific CD4(+) T cell epitopes using HLA-transgenic mice.

Science.gov (United States)

Gardyan, Adriane; Osen, Wolfram; Zörnig, Inka; Podola, Lilli; Agarwal, Maria; Aulmann, Sebastian; Ruggiero, Eliana; Schmidt, Manfred; Halama, Niels; Leuchs, Barbara; von Kalle, Christof; Beckhove, Philipp; Schneeweiss, Andreas; Jäger, Dirk; Eichmüller, Stefan B

2015-06-01

Breast cancer represents the second most common cancer type worldwide and has remained the leading cause of cancer-related deaths among women. The differentiation antigen NY-BR-1 appears overexpressed in invasive mammary carcinomas compared to healthy breast tissue, thus representing a promising target antigen for T cell based tumor immunotherapy approaches. Since efficient immune attack of tumors depends on the activity of tumor antigen-specific CD4(+) effector T cells, NY-BR-1 was screened for the presence of HLA-restricted CD4(+) T cell epitopes that could be included in immunological treatment approaches. Upon NY-BR-1-specific DNA immunization of HLA-transgenic mice and functional ex vivo analysis, a panel of NY-BR-1-derived library peptides was determined that specifically stimulated IFNγ secretion among splenocytes of immunized mice. Following in silico analyses, four candidate epitopes were determined which were successfully used for peptide immunization to establish NY-BR-1-specific, HLA-DRB1*0301- or HLA-DRB1*0401-restricted CD4(+) T cell lines from splenocytes of peptide immunized HLA-transgenic mice. Notably, all four CD4(+) T cell lines recognized human HLA-DR-matched dendritic cells (DC) pulsed with lysates of NY-BR-1 expressing human tumor cells, demonstrating natural processing of these epitopes also within the human system. Finally, CD4(+) T cells specific for all four CD4(+) T cell epitopes were detectable among PBMC of breast cancer patients, showing that CD4(+) T cell responses against the new epitopes are not deleted nor inactivated by self-tolerance mechanisms. Our results present the first NY-BR-1-specific HLA-DRB1*0301- and HLA-DRB1*0401-restricted T cell epitopes that could be exploited for therapeutic intervention against breast cancer. © 2014 UICC.

Soluble HLA-G and HLA-E Levels in Bone Marrow Plasma Samples Are Related to Disease Stage in Neuroblastoma Patients

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Fabio Morandi

2016-01-01

Full Text Available The role of nonclassical HLA-class Ib molecules HLA-G and HLA-E in the progression of Neuroblastoma (NB, the most common pediatric extracranial solid tumor, has been characterized in the last years. Since BM infiltration by NB cells is an adverse prognostic factor, we have here analyzed for the first time the concentration of soluble (sHLA-G and HLA-E in bone marrow (BM plasma samples from NB patients at diagnosis and healthy donors. sHLA-G and sHLA-E are present in BM plasma samples, and their levels were similar between NB patients and controls, thus suggesting that these molecules are physiologically released by resident or stromal BM cell populations. This hypothesis was supported by the finding that sHLA-G and sHLA-E levels did not correlate with BM infiltration and other adverse prognostic factors (MYCN amplification and age at diagnosis. In contrast, BM plasma levels of both molecules were higher in patients with metastatic disease than in patients with localized NB, thus suggesting that concentration of these molecules might be correlated with disease progression. The prognostic role of sHLA-G and sHLA-E concentration in the BM plasma for NB patients will be evaluated in future studies, by analyzing the clinical outcome of the same NB patients at follow-up.

Role of HLA adaptation in HIV evolution

DEFF Research Database (Denmark)

Kløverpris, Henrik N.; Leslie, Alasdair; Goulder, Philip

2016-01-01

Killing of HIV-infected cells by CD8+ T-cells imposes strong selection pressure on the virus toward escape. The HLA class I molecules that are successful in mediating some degree of control over the virus are those that tend to present epitopes in conserved regions of the proteome, such as in p24...... Gag, in which escape also comes at a significant cost to viral replicative capacity (VRC). In some instances, compensatory mutations can fully correct for the fitness cost of such an escape variant; in others, correction is only partial. The consequences of these events within the HIV-infected host......, and at the population level following transmission of escape variants, are discussed. The accumulation of escape mutants in populations over the course of the epidemic already shows instances of protective HLA molecules losing their impact, and in certain cases, a modest decline in HIV virulence in association...

The molecule HLA-G: radiosensitivity indicator of a human melanoma cell line

International Nuclear Information System (INIS)

Michelin, S.C.; Gallegos, C.E.; Dubner, D.L.; Baffa Trasci, S.; Favier, B.; Carosella, E.D.

2010-01-01

The physiological and pathological relevance of the HLA-G molecule (non-classical Human Leukocyte Antigen) has been motif of important research studies. Its distribution is restricted to only few tissues. HLA-G takes part in the implantation after in vitro fecundation, in graft tolerance, in auto-immune diseases, and in tumoral immune escape. Its expression has been demonstrated in more than 30% of tumors of 15 different histological types. Gamma radiation modulates HLA-G expression at the cell surface. However, its involvement in tumoral radiosensitivity has not been demonstrated yet. The objective of this work was to demonstrate if the HLA-G molecule intervenes in the radiosensibility of human melanoma cells cultured in vitro. For this purpose we used the human melanoma cell line M8, which was transfected with the plasmid containing the HLA-G gene (M8 HLA-G+) or with the plasmid alone, without the HLA-G gene (M8 pc DNA). Both cell lines were irradiated with 0, 2, 5 y 10 Gy and in all cases survival frequency was determined with the clonogenic assay. We observed a significant reduction in M8 HLA-G+ survival with respect to M8 pc DNA for all irradiation doses and was independent of doses. These results, if confirmed in other histological types, could postulate the HLA-G molecule as a tumoral radiosensitivity marker. The specific mechanism involved in the radiosensibility modification exerted by HLA-G has not been elucidated yet. (authors) [es

Involvement of HLA class I molecules in the immune escape of urologic tumors.

Science.gov (United States)

Carretero, R; Gil-Julio, H; Vázquez-Alonso, F; Garrido, F; Castiñeiras, J; Cózar, J M

2014-04-01

To analyze the influence of different alterations in human leukocyte antigen class I molecules (HLA I) in renal cell carcinoma, as well as in bladder and prostate cancer. We also study the correlation between HLA I expression and the progression of the disease and the response after immunotherapy protocols. It has been shown, experimentally, that the immune system can recognize and kill neoplastic cells. By analyzing the expression of HLA I molecules on the surface of cancer cells, we were able to study the tumor escape mechanisms against the immune system. Alteration or irreversible damage in HLA I molecules is used by the neoplastic cells to escape the immune system. The function of these molecules is to recognize endogenous peptides and present them to T cells of the immune system. There is a clear relationship between HLA I reversible alterations and success of therapy. Irreversible lesions also imply a lack of response to treatment. The immune system activation can reverse HLA I molecules expression in tumors with reversible lesions, whereas tumors with irreversible ones do not respond to such activation. Determine the type of altered HLA I molecules in tumors is of paramount importance when choosing the type of treatment to keep looking for therapeutic success. Those tumors with reversible lesions can be treated with traditional immunotherapy; however, tumour with irreversible alterations should follow alternative protocols, such as the use of viral vectors carrying the HLA genes to achieve damaged re-expression of the protein. From studies in urologic tumors, we can conclude that the HLA I molecules play a key role in these tumors escape to the immune system. Copyright © 2013 AEU. Published by Elsevier Espana. All rights reserved.

T cell suppression by naturally occurring HLA-G-expressing regulatory CD4+ T cells is IL-10-dependent and reversible.

Science.gov (United States)

Huang, Yu-Hwa; Zozulya, Alla L; Weidenfeller, Christian; Schwab, Nicholas; Wiendl, Heinz

2009-08-01

CD4(+) T cells constitutively expressing the immune-tolerogenic HLA-G have been described recently as a new type of nT(reg) (HLA-G(pos) T(reg)) in humans. HLA-G(pos) T(reg) accumulate at sites of inflammation and are potent suppressors of T cell proliferation in vitro, suggesting their role in immune regulation. We here characterize the mechanism of how CD4(+) HLA-G(pos) T(reg) influence autologous HLA-G(neg) T(resp) function. Using a suppression system free of APC, we demonstrate a T-T cell interaction, resulting in suppression of HLA-G(neg) T(resp), which is facilitated by TCR engagement on HLA-G(pos) T(reg). Suppression is independent of cell-cell contact and is reversible, as the removal of HLA-G(pos) T(reg) from the established coculture restored the proliferative capability of responder cells. Further, HLA-G(pos) T(reg)-mediated suppression critically depends on the secretion of IL-10 but not TGF-beta.

HLA-DR-expressing cells and T-lymphocytes in sural nerve biopsies

DEFF Research Database (Denmark)

Schrøder, H D; Olsson, T; Solders, G

1988-01-01

was confirmed. HLA-DR expression was found in all biopsies and thus was not restricted to any particular type of neuropathy. The HLA-DR expression appeared to correlate with severity and activity of the neuropathy. HLA-DR-expressing macrophages wrapping myelinated fibers were prominent in primary demyelinating......Thirty-five sural nerve biopsies were stained immunohistochemically for HLA-DR antigen. HLA-DR was expressed on nonmyelinating Schwann cells, macrophages, vascular endothelium, and perineurium. By means of double immunofluorescence staining the identity of the HLA-DR presenting structures...

Combination of Complement-Dependent Cytotoxicity and Relative Fluorescent Quantification of HLA Length Polymorphisms Facilitates the Detection of a Loss of Heterozygosity

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Klaus Witter

2014-01-01

Full Text Available Loss of heterozygosity (LOH is a common event in malignant cells. In this work we introduce a new approach to identify patients with loss of heterozygosity in the HLA region either at first diagnosis or after HLA mismatched allogeneic HSCT. Diagnosis of LOH requires a high purity of recipient target cells. FACS is time consuming and also frequently prevented by rather nonspecific or unknown immune phenotype. The approach for recipient cell enrichment is based on HLA targeted complement-dependent cytotoxicity (CDC. Relative fluorescent quantification (RFQ analysis of HLA intron length polymorphisms then allows analysis of HLA heterozygosity. The approach is exemplified in recent clinical cases illustrating the detection of an acquired allele loss. As illustrated in one case with DPB1, distinct HLA loci in donor and patient were sufficient for both proof of donor cell removal and evaluation of allele loss in the patient's leukemic cells. Results were confirmed using HLA-B RFQ analysis and leukemia-associated aberrant immunophenotype (LAIP based cell sort. Both results confirmed suspected loss of HLA heterozygosity. Our approach complements or substitutes for FACS-based cell enrichment; hence it may be further developed as novel routine diagnostic tool. This allows rapid recipient cell purification and testing for loss of HLA heterozygosity before and after allogeneic HSCT in easily accessible peripheral blood samples.

Impact of HLA diversity on donor selection in organ and stem cell transplantation.

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Tiercy, Jean-Marie; Claas, Frans

2013-01-01

The human major histocompatibility complex is a multigene system encoding polymorphic human leucocyte antigens (HLA) that present peptides derived from pathogens to the immune system. The high diversity of HLA alleles and haplotypes in the worldwide populations represents a major barrier to organ and allogeneic hematopoietic stem cell transplantation, because HLA incompatibilities are efficiently recognized by T and B lymphocytes. In organ transplantation, pre-transplant anti-HLA antibodies need to be taken into account for organ allocation. Although HLA-incompatible transplants can be performed thanks to immunosuppressive drugs, the de novo production of anti-HLA antibodies still represents a major cause of graft failure. The HLAMatchmaker computer algorithm determines the immunogenicity of HLA mismatches and allows to define HLA antigens that will not induce an antibody response. Because of the much higher stringency of HLA compatibility criteria in stem cell transplantation, the best donor is a HLA genotypically identical sibling. However, more than 50% of the transplants are now performed with hematopoietic stem cells from volunteer donors selected from the international registry. The development of European national registries covering populations with different HLA haplotype frequencies is essential for optimizing donor search algorithms and providing the best chance for European patients to find a fully compatible donor.

HLA-G Expression on Blasts and Tolerogenic Cells in Patients Affected by Acute Myeloid Leukemia

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Grazia Locafaro

2014-01-01

Full Text Available Human Leukocyte Antigen-G (HLA-G contributes to cancer cell immune escape from host antitumor responses. The clinical relevance of HLA-G in several malignancies has been reported. However, the role of HLA-G expression and functions in Acute Myeloid Leukemia (AML is still controversial. Our group identified a subset of tolerogenic dendritic cells, DC-10 that express HLA-G and secrete IL-10. DC-10 are present in the peripheral blood and are essential in promoting and maintaining tolerance via the induction of adaptive T regulatory (Treg cells. We investigated HLA-G expression on blasts and the presence of HLA-G-expressing DC-10 and CD4+ T cells in the peripheral blood of AML patients at diagnosis. Moreover, we explored the possible influence of the 3′ untranslated region (3′UTR of HLA-G, which has been associated with HLA-G expression, on AML susceptibility. Results showed that HLA-G-expressing DC-10 and CD4+ T cells are highly represented in AML patients with HLA-G positive blasts. None of the HLA-G variation sites evaluated was associated with AML susceptibility. This is the first report describing HLA-G-expressing DC-10 and CD4+ T cells in AML patients, suggesting that they may represent a strategy by which leukemic cells escape the host’s immune system. Further studies on larger populations are required to verify our findings.

Effect of T-cell-epitope matching at HLA-DPB1 in recipients of unrelated-donor haemopoietic-cell transplantation: a retrospective study

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Fleischhauer, Katharina; Gooley, Theodore; Malkki, Mari; Bardy, Peter; Bignon, Jean-Denis; Dubois, Valérie; Horowitz, Mary M; Madrigal, J Alejandro; Morishima, Yasuo; Oudshoorn, Machteld; Ringden, Olle; Spellman, Stephen; Velardi, Andrea; Zino, Elisabetta; Petersdorf, Effie W

2013-01-01

Summary Background The risks after unrelated-donor haemopoietic-cell transplantation with matched HLA-A, HLA-B, HLA-C, HLA-DRB1, HLA-DQB1 alleles between donor and recipient (10/10 matched) can be decreased by selection of unrelated donors who also match for HLA-DPB1; however, such donors are difficult to find. Classification of HLA-DPB1 mismatches based on T-cell-epitope groups could identify mismatches that might be tolerated (permissive) and those that would increase risks (non-permissive) after transplantation. We did a retrospective study to compare outcomes between permissive and non-permissive HLA-DPB1 mismatches in unrelated-donor haemopoietic-cell transplantation. Methods HLA and clinical data for unrelated-donor transplantations submitted to the International Histocompatibility Working Group in haemopoietic-cell transplantation were analysed retrospectively. HLA-DPB1 T-cell-epitope groups were assigned according to a functional algorithm based on alloreactive T-cell crossreactivity patterns. Recipients and unrelated donors matching status were classified as HLA-DPB1 match, non-permissive HLA-DPB1 mismatch (those with mismatched T-cell-epitope groups), or permissive HLA-DPB1 mismatch (those with matched T-cell-epitope groups). The clinical outcomes assessed were overall mortality, non-relapse mortality, relapse, and severe (grade 3–4) acute graft-versus-host disease (aGvHD). Findings Of 8539 transplantations, 5428 (64%) were matched for ten of ten HLA alleles (HLA 10/10 matched) and 3111 (36%) for nine of ten alleles (HLA 9/10 matched). Of the group overall, 1719 (20%) were HLA-DPB1 matches, 2670 (31%) non-permissive HLA-DPB1 mismatches, and 4150 (49%) permissive HLA-DPB1 mismatches. In HLA 10/10-matched transplantations, non-permissive mismatches were associated with a significantly increased risk of overall mortality (hazard ratio [HR] 1·15, 95% CI 1·05–1·25; p=0·002), non-relapse mortality (1·28, 1·14–1·42; pKarolinska Institutet; and

Single Cell HLA Matching Feasibility by Whole Genomic Amplification and Nested PCR

Institute of Scientific and Technical Information of China (English)

Xiao-hong Li; Fang-yin Meng

2004-01-01

@@ PCR based single-cell DNA analysis has been widely used in forensic science, preimplantation genetic diagnosis and so on. However, the original sample cannot be efficiently retrieved following single cell PCR, consequently the amount of information gained is limited. HLA system is too sophisticated that it is very hard to complete HLA typing by single cell. A Taq polymerase-based method using random primers to amplify whole genome termed as whole genome amplification (WGA) has demonstrated to be a useful method in increasing the copies of minimum sample. We establish a technique in this study to amplify HLA-A and HLA-B loci at same time in a single cell using WGA.

Heme Oxygenase-1 Inhibits HLA Class I Antibody-Dependent Endothelial Cell Activation.

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Eva Zilian

Full Text Available Antibody-mediated rejection (AMR is a key limiting factor for long-term graft survival in solid organ transplantation. Human leukocyte antigen (HLA class I (HLA I antibodies (Abs play a major role in the pathogenesis of AMR via their interactions with HLA molecules on vascular endothelial cells (ECs. The antioxidant enzyme heme oxygenase (HO-1 has anti-inflammatory functions in the endothelium. As complement-independent effects of HLA I Abs can activate ECs, it was the goal of the current study to investigate the role of HO-1 on activation of human ECs by HLA I Abs. In cell cultures of various primary human macro- and microvascular ECs treatment with monoclonal pan- and allele-specific HLA I Abs up-regulated the expression of inducible proinflammatory adhesion molecules and chemokines (vascular cell adhesion molecule-1 [VCAM-1], intercellular cell adhesion molecule-1 [ICAM-1], interleukin-8 [IL-8] and monocyte chemotactic protein 1 [MCP-1]. Pharmacological induction of HO-1 with cobalt-protoporphyrin IX reduced, whereas inhibition of HO-1 with either zinc-protoporphyrin IX or siRNA-mediated knockdown increased HLA I Ab-dependent up-regulation of VCAM-1. Treatment with two carbon monoxide (CO-releasing molecules, which liberate the gaseous HO product CO, blocked HLA I Ab-dependent EC activation. Finally, in an in vitro adhesion assay exposure of ECs to HLA I Abs led to increased monocyte binding, which was counteracted by up-regulation of HO-1. In conclusion, HLA I Ab-dependent EC activation is modulated by endothelial HO-1 and targeted induction of this enzyme may be a novel therapeutic approach for the treatment of AMR in solid organ transplantation.

HLA-G, immunocompetent cells and pregnancy outcome : a case of modulation

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Emmer, Peter Martin

2003-01-01

In this thesis we address the immunomodulatory role of human leukocyte antigen G (HLA-G). The placental trophoblast cells express HLA-G as membrane bound and soluble form (due to alternative splicing) at the fetomaternal interface. HLA-G putatively interacts with the maternal endometrial (decidual)

Elevated HLA-A expression impairs HIV control through inhibition of NKG2A-expressing cells.

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Ramsuran, Veron; Naranbhai, Vivek; Horowitz, Amir; Qi, Ying; Martin, Maureen P; Yuki, Yuko; Gao, Xiaojiang; Walker-Sperling, Victoria; Del Prete, Gregory Q; Schneider, Douglas K; Lifson, Jeffrey D; Fellay, Jacques; Deeks, Steven G; Martin, Jeffrey N; Goedert, James J; Wolinsky, Steven M; Michael, Nelson L; Kirk, Gregory D; Buchbinder, Susan; Haas, David; Ndung'u, Thumbi; Goulder, Philip; Parham, Peter; Walker, Bruce D; Carlson, Jonathan M; Carrington, Mary

2018-01-05

The highly polymorphic human leukocyte antigen ( HLA ) locus encodes cell surface proteins that are critical for immunity. HLA-A expression levels vary in an allele-dependent manner, diversifying allele-specific effects beyond peptide-binding preference. Analysis of 9763 HIV-infected individuals from 21 cohorts shows that higher HLA-A levels confer poorer control of HIV. Elevated HLA-A expression provides enhanced levels of an HLA-A-derived signal peptide that specifically binds and determines expression levels of HLA-E, the ligand for the inhibitory NKG2A natural killer (NK) cell receptor. HLA-B haplotypes that favor NKG2A-mediated NK cell licensing (i.e., education) exacerbate the deleterious effect of high HLA-A on HIV control, consistent with NKG2A-mediated inhibition impairing NK cell clearance of HIV-infected targets. Therapeutic blockade of HLA-E:NKG2A interaction may yield benefit in HIV disease. Copyright © 2017, American Association for the Advancement of Science.

Empty conformers of HLA-B preferentially bind CD8 and regulate CD8+ T cell function.

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Geng, Jie; Altman, John D; Krishnakumar, Sujatha; Raghavan, Malini

2018-05-09

When complexed with antigenic peptides, human leukocyte antigen (HLA) class I (HLA-I) molecules initiate CD8 + T cell responses via interaction with the T cell receptor (TCR) and co-receptor CD8. Peptides are generally critical for the stable cell surface expression of HLA-I molecules. However, for HLA-I alleles such as HLA-B*35:01, peptide-deficient (empty) heterodimers are thermostable and detectable on the cell surface. Additionally, peptide-deficient HLA-B*35:01 tetramers preferentially bind CD8 and to a majority of blood-derived CD8 + T cells via a CD8-dependent binding mode. Further functional studies reveal that peptide-deficient conformers of HLA-B*35:01 do not directly activate CD8 + T cells, but accumulate at the immunological synapse in antigen-induced responses, and enhance cognate peptide-induced cell adhesion and CD8 + T cell activation. Together, these findings indicate that HLA-I peptide occupancy influences CD8 binding affinity, and reveal a new set of regulators of CD8 + T cell activation, mediated by the binding of empty HLA-I to CD8. © 2018, Geng et al.

Separate developmental programs for HLA-A and -B cell surface expression during differentiation from embryonic stem cells to lymphocytes, adipocytes and osteoblasts.

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Hardee J Sabir

Full Text Available A major problem of allogeneic stem cell therapy is immunologically mediated graft rejection. HLA class I A, B, and Cw antigens are crucial factors, but little is known of their respective expression on stem cells and their progenies. We have recently shown that locus-specific expression (HLA-A, but not -B is seen on some multipotent stem cells, and this raises the question how this is in other stem cells and how it changes during differentiation. In this study, we have used flow cytometry to investigate the cell surface expression of HLA-A and -B on human embryonic stem cells (hESC, human hematopoietic stem cells (hHSC, human mesenchymal stem cells (hMSC and their fully-differentiated progenies such as lymphocytes, adipocytes and osteoblasts. hESC showed extremely low levels of HLA-A and no -B. In contrast, multipotent hMSC and hHSC generally expressed higher levels of HLA-A and clearly HLA-B though at lower levels. IFNγ induced HLA-A to very high levels on both hESC and hMSC and HLA-B on hMSC. Even on hESC, a low expression of HLA-B was achieved. Differentiation of hMSC to osteoblasts downregulated HLA-A expression (P = 0.017. Interestingly HLA class I on T lymphocytes differed between different compartments. Mature bone marrow CD4(+ and CD8(+ T cells expressed similar HLA-A and -B levels as hHSC, while in the peripheral blood they expressed significantly more HLA-B7 (P = 0.0007 and P = 0.004 for CD4(+ and CD8(+ T cells, respectively. Thus different HLA loci are differentially regulated during differentiation of stem cells.

Characterization of the Endothelial Cell Cytoskeleton following HLA Class I Ligation

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Ziegler, Mary E.; Souda, Puneet; Jin, Yi-Ping; Whitelegge, Julian P.; Reed, Elaine F.

2012-01-01

Background Vascular endothelial cells (ECs) are a target of antibody-mediated allograft rejection. In vitro, when the HLA class I molecules on the surface of ECs are ligated by anti-HLA class I antibodies, cell proliferation and survival pathways are activated and this is thought to contribute to the development of antibody-mediated rejection. Crosslinking of HLA class I molecules by anti-HLA antibodies also triggers reorganization of the cytoskeleton, which induces the formation of F-actin stress fibers. HLA class I induced stress fiber formation is not well understood. Methodology and Principal Findings The present study examines the protein composition of the cytoskeleton fraction of ECs treated with HLA class I antibodies and compares it to other agonists known to induce alterations of the cytoskeleton in endothelial cells. Analysis by tandem mass spectrometry revealed unique cytoskeleton proteomes for each treatment group. Using annotation tools a candidate list was created that revealed 12 proteins, which were unique to the HLA class I stimulated group. Eleven of the candidate proteins were phosphoproteins and exploration of their predicted kinases provided clues as to how these proteins may contribute to the understanding of HLA class I induced antibody-mediated rejection. Three of the candidates, eukaryotic initiation factor 4A1 (eIF4A1), Tropomyosin alpha 4-chain (TPM4) and DDX3X, were further characterized by Western blot and found to be associated with the cytoskeleton. Confocal microscopy analysis showed that class I ligation stimulated increased eIF4A1 co-localization with F-actin and paxillin. Conclusions/Significance Colocalization of eIF4A1 with F-actin and paxillin following HLA class I ligation suggests that this candidate protein could be a target for understanding the mechanism(s) of class I mediated antibody-mediated rejection. This proteomic approach for analyzing the cytoskeleton of ECs can be applied to other agonists and various cells types

Single-hit mechanism of tumour cell killing by radiation.

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Chapman, J D

2003-02-01

To review the relative importance of the single-hit mechanism of radiation killing for tumour response to 1.8-2.0 Gy day(-1) fractions and to low dose-rate brachytherapy. Tumour cell killing by ionizing radiation is well described by the linear-quadratic equation that contains two independent components distinguished by dose kinetics. Analyses of tumour cell survival curves that contain six or more dose points usually provide good estimates of the alpha- and beta-inactivation coefficients. Superior estimates of tumour cell intrinsic radiosensitivity are obtained when synchronized populations are employed. The characteristics of single-hit inactivation of tumour cells are reviewed and compared with the characteristics of beta-inactivation. Potential molecular targets associated with single-hit inactivation are discussed along with strategies for potentiating cell killing by this mechanism. The single-hit mechanism of tumour cell killing shows no dependence on dose-rate and, consequently, no evidence of sublethal damage repair. It is uniquely potentiated by high linear-energy-transfer radiation, exhibits a smaller oxygen enhancement ratio and exhibits a larger indirect effect by hydroxyl radicals than the beta-mechanism. alpha-inactivation coefficients vary slightly throughout interphase but mitotic cells exhibit extremely high alpha-coefficients in the range of those observed for lymphocytes and some repair-deficient cells. Evidence is accumulating to suggest that chromatin in compacted form could be a radiation-hypersensitive target associated with single-hit radiation killing. Analyses of tumour cell survival curves demonstrate that it is the single-hit mechanism (alpha) that determines the majority of cell killing after doses of 2Gy and that this mechanism is highly variable between tumour cell lines. The characteristics of single-hit inactivation are qualitatively and quantitatively distinct from those of beta-inactivation. Compacted chromatin in tumour cells

Metformin kills and radiosensitizes cancer cells and preferentially kills cancer stem cells

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Song, Chang W.; Lee, Hyemi; Dings, Ruud P. M.; Williams, Brent; Powers, John; Santos, Troy Dos; Choi, Bo-Hwa; Park, Heon Joo

2012-01-01

The anti-cancer effects of metformin, the most widely used drug for type 2 diabetes, alone or in combination with ionizing radiation were studied with MCF-7 human breast cancer cells and FSaII mouse fibrosarcoma cells. Clinically achievable concentrations of metformin caused significant clonogenic death in cancer cells. Importantly, metformin was preferentially cytotoxic to cancer stem cells relative to non-cancer stem cells. Metformin increased the radiosensitivity of cancer cells in vitro, and significantly enhanced the radiation-induced growth delay of FSaII tumors (s.c.) in the legs of C3H mice. Both metformin and ionizing radiation activated AMPK leading to inactivation of mTOR and suppression of its downstream effectors such as S6K1 and 4EBP1, a crucial signaling pathway for proliferation and survival of cancer cells, in vitro as well as in the in vivo tumors. Conclusion: Metformin kills and radiosensitizes cancer cells and eradicates radioresistant cancer stem cells by activating AMPK and suppressing mTOR. PMID:22500211

Complex antigen presentation pathway for an HLA-A*0201-restricted epitope from Chikungunya 6K protein.

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Lorente, Elena; Barriga, Alejandro; García-Arriaza, Juan; Lemonnier, François A; Esteban, Mariano; López, Daniel

2017-10-01

The adaptive cytotoxic T lymphocyte (CTL)-mediated immune response is critical for clearance of many viral infections. These CTL recognize naturally processed short viral antigenic peptides bound to human leukocyte antigen (HLA) class I molecules on the surface of infected cells. This specific recognition allows the killing of virus-infected cells. The T cell immune T cell response to Chikungunya virus (CHIKV), a mosquito-borne Alphavirus of the Togaviridae family responsible for severe musculoskeletal disorders, has not been fully defined; nonetheless, the importance of HLA class I-restricted immune response in this virus has been hypothesized. By infection of HLA-A*0201-transgenic mice with a recombinant vaccinia virus that encodes the CHIKV structural polyprotein (rVACV-CHIKV), we identified the first human T cell epitopes from CHIKV. These three novel 6K transmembrane protein-derived epitopes are presented by the common HLA class I molecule, HLA-A*0201. One of these epitopes is processed and presented via a complex pathway that involves proteases from different subcellular locations. Specific chemical inhibitors blocked these events in rVACV-CHIKV-infected cells. Our data have implications not only for the identification of novel Alphavirus and Togaviridae antiviral CTL responses, but also for analyzing presentation of antigen from viruses of different families and orders that use host proteinases to generate their mature envelope proteins.

The Dual Role of HLA-G in Cancer

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Nathalie Rouas-Freiss

2014-01-01

Full Text Available We here review the current data on the role of HLA-G in cancer based on recent findings of an unexpected antitumor activity of HLA-G in hematological malignancies. For the past decade, HLA-G has been described as a tumor-escape mechanism favoring cancer progression, and blocking strategies have been proposed to counteract it. Aside from these numerous studies on solid tumors, recent data showed that HLA-G inhibits the proliferation of malignant B cells due to the interaction between HLA-G and its receptor ILT2, which mediates negative signaling on B cell proliferation. These results led to the conjecture that, according to the malignant cell type, HLA-G should be blocked or conversely induced to counteract tumor progression. In this context, we will here present (i the dual role of HLA-G in solid and liquid tumors with special emphasis on (ii the HLA-G active structures and their related ILT2 and ILT4 receptors and (iii the current knowledge on regulatory mechanisms of HLA-G expression in tumors.

Donor-specific Anti-HLA antibodies in allogeneic hematopoietic stem cell transplantation

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Sarah Morin-Zorman

2016-08-01

Full Text Available Allogeneic Hematopoietic Stem Cell Transplantation (AHSCT is a curative treatment for a wide variety of hematological diseases. In 30% of the cases, a geno-identical donor is available. Any other situation displays some level of Human Leukocyte Antigen (HLA incompatibility between donor and recipient. Deleterious effects of anti-HLA immunization have long been recognized in solid organ transplant recipients. More recently, anti-HLA immunization was shown to increase the risk of Primary Graft Failure (PGF, a severe complication of AHSCT that occurs in 3 to 4% of matched unrelated donor transplantation and up to 15% in cord blood transplantation and T-cell depleted haplo-identical stem cell transplantation. Rates of PGF in patients with DSA were reported to be between 24 to 83% with the highest rates in haplo-identical and cord blood transplantation recipients. This led to the recommendation of anti-HLA antibody screening to detect Donor Specific Antibodies (DSA in recipients prior to AHSCT. In this review, we highlight the role of anti-HLA antibodies in AHSCT and the mechanisms that may lead to PGF in patients with DSA, and discuss current issues in the field.

No association between infections, HLA type and other transplant-related factors and risk of cutaneous squamous cell carcinoma in solid organ transplant recipients.

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Ingvar, Åsa; Ekström Smedby, Karin; Lindelöf, Bernt; Fernberg, Pia; Bellocco, Rino; Tufveson, Gunnar; Höglund, Petter; Adami, Johanna

2012-11-01

Recipients of solid organ transplants are at a markedly increased risk of cutaneous squamous cell carcinoma (SCC). We investigated potential associations between post-transplant infections, HLA type, and other transplant-related factors and risk of SCC, taking immuno-suppressive treatment into account. A population-based case-control study was conducted. All patients who developed SCC during follow-up (1970-1997) were eligible as cases (n = 207). Controls (n = 189) were individually matched to the cases on age and calendar period of transplantation. Detailed exposure information was collected through an extensive, blinded review of medical records. Odds ratios were computed with conditional logistic regression. There were no significant associations with any infectious agents, or with number and timing of infections, specific HLA-type, donor characteristics, or other transplant characteristics and risk of post-transplant SCC. These results suggest that risk of post-transplant SCC is neither closely related to specific post-transplant infectious disorders, nor to the infectious load or specific HLA types.

Characterization of a novel HLA-B*39:01:01-related allele, HLA-B*39:130, by cloning and phasing.

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Li, L X; Tian, W; Zhu, F M; Wang, W Y; Cai, J H

2017-12-01

A novel HLA-B*39:01:01-related variant, HLA-B*39:130, has been identified in a normal individual of Han ethnicity in Hunan province, southern China. Following Sanger polymerase chain reaction-sequence-based typing (PCR-SBT), this new allele was further confirmed by cloning, phasing and sequencing. Aligned with HLA-B*39:01:01, HLA-B*39:130 has a nonsynonymous thymine substitution at nucleotide position 94 in exon 4, resulting in amino acid change from threonine to isoleucine at codon 214 (ACA→ATA) of the mature HLA-BmRNA molecule. © 2017 John Wiley & Sons Ltd.

Improved survival of acute lymphoblastic leukemia patients of HLA-A3/11 absent for donor KIR3DL2 after non-T-cell depleted HLA-identical sibling hematopoietic stem cells transplantation

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farhad shahsavar

2011-08-01

Conclusion: These data indicate that the absence of HLA class I ligand in the recipient for donor-inhibitory KIR can be a prognostic factor for transplantation outcomes in non-T-cell depleted HLA-identical sibling hematopoietic stem-cell transplantation and that the lack of HLA-A3/11 for donor KIR3DL2 can contribute to improved survival for patients with ALL.

HLA-A*01:03, HLA-A*24:02, HLA-B*08:01, HLA-B*27:05, HLA-B*35:01, HLA-B*44:02, and HLA-C*07:01 Monochain Transgenic/H-2 Class I Null Mice

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Boucherma, Rachid; Kridane-Miledi, Hédia; Bouziat, Romain

2013-01-01

We have generated a panel of transgenic mice expressing HLA-A*01:03, -A*24:02, -B*08:01, -B*27:05, -B*35:01, -B*44:02, or -C*07:01 as chimeric monochain molecules (i.e., appropriate HLA α1α2 H chain domains fused with a mouse α3 domain and covalently linked to human β2-microglobulin). Whereas...... a quantitative and qualitative restoration of the peripheral CD8(+) T cell repertoire, which exhibited a TCR diversity comparable with C57BL/6 WT mice. Potent epitope-specific, HLA-restricted, IFN-γ-producing CD8(+) T cell responses were generated against known reference T cell epitopes after either peptide...

Mapping the HLA ligandome of Colorectal Cancer Reveals an Imprint of Malignant Cell Transformation.

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Löffler, Markus W; Kowalewski, Daniel J; Backert, Linus; Bernhardt, Jörg; Adam, Patrick; Schuster, Heiko; Dengler, Florian; Backes, Daniel; Kopp, Hans-Georg; Beckert, Stefan; Wagner, Silvia; Königsrainer, Ingmar; Kohlbacher, Oliver; Kanz, Lothar; Königsrainer, Alfred; Rammensee, Hans-Georg; Stevanovic, Stefan; Haen, Sebastian P

2018-05-22

Immune cell infiltrates have proven highly relevant for colorectal carcinoma (CRC) prognosis, making CRC a promising candidate for immunotherapy. Since tumors interact with the immune system via HLA-presented peptide ligands, exact knowledge of the peptidome constitution is fundamental for understanding this relationship. Here we comprehensively describe the naturally presented HLA-ligandome of CRC and corresponding non-malignant colon (NMC) tissue. Mass spectrometry identified 35,367 and 28,132 HLA-class I ligands on CRC and NMC, attributable to 7,684 and 6,312 distinct source proteins, respectively. Cancer-exclusive peptides were assessed on source protein level using Kyoto Encyclopedia of Genes and Genomes (KEGG) and protein analysis through evolutionary relationships (PANTHER), revealing pathognomonic CRC-associated pathways including Wnt, TGF-β, PI3K, p53, and RTK-RAS. Relative quantitation of peptide presentation on paired CRC and NMC tissue further identified source proteins from cancer- and infection-associated pathways to be over-represented merely within the CRC ligandome. From the pool of tumor-exclusive peptides, a selected HLA-ligand subset was assessed for immunogenicity, with the majority exhibiting an existing T cell repertoire. Overall, these data show that the HLA-ligandome reflects cancer-associated pathways implicated in CRC oncogenesis, suggesting that alterations in tumor cell metabolism could result in cancer-specific, albeit not mutation-derived tumor-antigens. Hence, a defined pool of unique tumor peptides, attributable to complex cellular alterations that are exclusive to malignant cells might comprise promising candidates for immunotherapeutic applications. Copyright ©2018, American Association for Cancer Research.

Homozygous HLA-C1 is Associated with Reduced Risk of Relapse after HLA-Matched Transplantation in Patients with Myeloid Leukemia.

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Arima, Nobuyoshi; Kanda, Junya; Tanaka, Junji; Yabe, Toshio; Morishima, Yasuo; Kim, Sung-Won; Najima, Yuho; Ozawa, Yukiyasu; Eto, Tetsuya; Kanamori, Heiwa; Mori, Takehiko; Kobayashi, Naoki; Kondo, Tadakazu; Nakamae, Hirohisa; Uchida, Naoyuki; Inoue, Masami; Fukuda, Takahiro; Ichinohe, Tatsuo; Atsuta, Yoshiko; Kanda, Yoshinobu

2018-04-01

Natural killer (NK) cells assume graft-versus-leukemia alloreactivity after hematopoietic stem cell transplantation (HSCT) through their inhibitory killer cell immunoglobulin-like receptors (KIRs). KIR2D family members recognize HLA-C alleles with Asn80 (HLA-C1) or Lys80 (HLA-C2). The predominance of HLA-C1 over HLA-C2 and the frequent presence of KIR2DL1 are characteristic of Japanese people. We compared clinical outcomes among homozygous HLA-C1 (HLA-C1/C1) patients and heterozygous HLA-C1/C2 patients who underwent HLA-matched HSCT for hematologic malignancies by assessing the data of 10,638 patients from the Japanese national registry. HLA-C1/C1 recipients had a lower rate of relapse than HLA-C1/C2 recipients after transplantation for acute myelogenous leukemia (AML) (hazard ratio [HR], .79; P = .006) and chronic myelogenous leukemia (CML) (HR, .48; P = .025), but not for acute lymphoblastic leukemia (HR, 1.36), lymphoma (HR, .97), or low-grade myelodysplastic syndrome (HR, 1.40). We then grouped AML and CML patients together and divided them into several subgroups. Advantages of HLA-C1/C1 recipients over HLA-C1/C2 recipients regarding relapse were observed irrespective of donor relation (related: HR, .79, P = .069; unrelated: HR, .77, P = .022), preparative regimen (myeloablative: HR, .79, P = .014; reduced intensity: HR, .73, P = .084), and occurrence of acute graft-versus-host disease (yes: HR, .70, P = .122; no, HR .71, P = .026) or cytomegalovirus reactivation (reactivated: HR .67,P = .054; nonreactivated: HR .71, P = .033); however, these advantages were not observed in recipients with a delay in achieving complete chimerism (HR, 1.06). The advantage of decreasing relapse and extending relapse-free survival of C1/1 over C1/2 KIR-ligand status was most pronounced in T cell-depleted HSCT (HR, .27; P < .001 and HR, .30; P = .002, respectively) and in children age <15 years (HR, .29; P < .001 and HR .31; P�

HLA-B*14

DEFF Research Database (Denmark)

Leitman, Ellen M.; Willberg, Christian B.; Tsai, Ming Han

2017-01-01

Immune control of human immunodeficiency virus type 1 (HIV) infection is typically associated with effective Gag-specific CD8+ T-cell responses. We here focus on HLA-B*14, which protects against HIV disease progression, but the immunodominant HLA-B*14-restricted anti-HIV response is Env specific...... higher functional avidity (P associated protection against HIV disease progression...... is significantly greater for HLA-B*14:02 than for HLA-B*14:01, consistent with the superior antiviral efficacy of the HLA-B*14-EL9 response. Thus, although Gag-specific CD8+ T-cell responses may usually have greater anti-HIV efficacy, factors independent of protein specificity, including functional avidity...

HLA Match Likelihoods for Hematopoietic Stem-Cell Grafts in the U.S. Registry

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Gragert, Loren; Eapen, Mary; Williams, Eric; Freeman, John; Spellman, Stephen; Baitty, Robert; Hartzman, Robert; Rizzo, J. Douglas; Horowitz, Mary; Confer, Dennis; Maiers, Martin

2018-01-01

Background Hematopoietic stem-cell transplantation (HSCT) is a potentially lifesaving therapy for several blood cancers and other diseases. For patients without a suitable related HLA-matched donor, unrelated-donor registries of adult volunteers and banked umbilical cord–blood units, such as the Be the Match Registry operated by the National Marrow Donor Program (NMDP), provide potential sources of donors. Our goal in the present study was to measure the likelihood of finding a suitable donor in the U.S. registry. Methods Using human HLA data from the NMDP donor and cord-blood-unit registry, we built population-based genetic models for 21 U.S. racial and ethnic groups to predict the likelihood of identifying a suitable donor (either an adult donor or a cord-blood unit) for patients in each group. The models incorporated the degree of HLA matching, adult-donor availability (i.e., ability to donate), and cord-blood-unit cell dose. Results Our models indicated that most candidates for HSCT will have a suitable (HLA-matched or minimally mismatched) adult donor. However, many patients will not have an optimal adult donor — that is, a donor who is matched at high resolution at HLA-A, HLA-B, HLA-C, and HLA-DRB1. The likelihood of finding an optimal donor varies among racial and ethnic groups, with the highest probability among whites of European descent, at 75%, and the lowest probability among blacks of South or Central American descent, at 16%. Likelihoods for other groups are intermediate. Few patients will have an optimal cord-blood unit — that is, one matched at the antigen level at HLA-A and HLA-B and matched at high resolution at HLA-DRB1. However, cord-blood units mismatched at one or two HLA loci are available for almost all patients younger than 20 years of age and for more than 80% of patients 20 years of age or older, regardless of racial and ethnic background. Conclusions Most patients likely to benefit from HSCT will have a donor. Public investment in

Separate Developmental Programs for HLA-A and -B Cell Surface Expression during Differentiation from Embryonic Stem Cells to Lymphocytes, Adipocytes and Osteoblasts

DEFF Research Database (Denmark)

Sabir, Hardee J; Nehlin, Jan O; Qanie, Diyako

2013-01-01

-A, but not -B) is seen on some multipotent stem cells, and this raises the question how this is in other stem cells and how it changes during differentiation. In this study, we have used flow cytometry to investigate the cell surface expression of HLA-A and -B on human embryonic stem cells (hESC), human...... hematopoietic stem cells (hHSC), human mesenchymal stem cells (hMSC) and their fully-differentiated progenies such as lymphocytes, adipocytes and osteoblasts. hESC showed extremely low levels of HLA-A and no -B. In contrast, multipotent hMSC and hHSC generally expressed higher levels of HLA-A and clearly HLA......A major problem of allogeneic stem cell therapy is immunologically mediated graft rejection. HLA class I A, B, and Cw antigens are crucial factors, but little is known of their respective expression on stem cells and their progenies. We have recently shown that locus-specific expression (HLA...

Platelet transfusion refractoriness attributable to HLA antibodies produced by donor-derived cells after allogeneic bone marrow transplantation from one HLA-antigen-mismatched mother.

Science.gov (United States)

Hatakeyama, Naoki; Hori, Tsukasa; Yamamoto, Masaki; Inazawa, Natsuko; Iesato, Kotoe; Miyazaki, Toru; Ikeda, Hisami; Tsutsumi, Hiroyuki; Suzuki, Nobuhiro

2011-12-01

PTR is a serious problem in patients being treated for hematologic disorders. Two patients with acute leukemia developed PTR after allogeneic BMT from one HLA-antigen-mismatched mother attributable to HLA antibodies, which could not be detected in their serum before BMT. HLA antibodies, whose specificity resembled that of each patient, were detected in each donor's serum. Each donor had probably been immunized during pregnancy by their partner's HLA antigens expressed by the fetus, consequently, transplanted donor-derived cells provoked HLA antibodies in each recipient early after BMT, and those HLA antibodies induced PTR. If the mothers are selected as donors for their children, they should be tested for the presence of HLA antibodies. © 2010 John Wiley & Sons A/S.

Activated Allogeneic NK Cells Preferentially Kill Poor Prognosis B-Cell Chronic Lymphocytic Leukemia Cells.

Science.gov (United States)

Sánchez-Martínez, Diego; Lanuza, Pilar M; Gómez, Natalia; Muntasell, Aura; Cisneros, Elisa; Moraru, Manuela; Azaceta, Gemma; Anel, Alberto; Martínez-Lostao, Luis; Villalba, Martin; Palomera, Luis; Vilches, Carlos; García Marco, José A; Pardo, Julián

2016-01-01

Mutational status of TP53 together with expression of wild-type (wt) IGHV represents the most widely accepted biomarkers, establishing a very poor prognosis in B-cell chronic lymphocytic leukemia (B-CLL) patients. Adoptive cell therapy using allogeneic HLA-mismatched Natural killer (NK) cells has emerged as an effective and safe alternative in the treatment of acute myeloid and lymphoid leukemias that do not respond to traditional therapies. We have described that allogeneic activated NK cells eliminate hematological cancer cell lines with multidrug resistance acquired by mutations in the apoptotic machinery. This effect depends on the activation protocol, being B-lymphoblastoid cell lines (LCLs) the most effective stimulus to activate NK cells. Here, we have further analyzed the molecular determinants involved in allogeneic NK cell recognition and elimination of B-CLL cells, including the expression of ligands of the main NK cell-activating receptors (NKG2D and NCRs) and HLA mismatch. We present preliminary data suggesting that B-CLL susceptibility significantly correlates with HLA mismatch between NK cell donor and B-CLL patient. Moreover, we show that the sensitivity of B-CLL cells to NK cells depends on the prognosis based on TP53 and IGHV mutational status. Cells from patients with worse prognosis (mutated TP53 and wt IGHV ) are the most susceptible to activated NK cells. Hence, B-CLL prognosis may predict the efficacy of allogenic activated NK cells, and, thus, NK cell transfer represents a good alternative to treat poor prognosis B-CLL patients who present a very short life expectancy due to lack of effective treatments.

HLA-G molecule as inductor of immunotolerance

International Nuclear Information System (INIS)

Alfonso Valdes, Maria E

2009-01-01

HLA-G are molecules are (non-classic) class I antigens from main histocompatibility system. There are sis isoforms of HLA-G antigen codifying four proteins united to a membrane (HLA-G1, HLA-G2, HLA-G3, HLA-G4), and three soluble isoforms (HLA-G5, HLA-G6, HLA-G7). The first ones are expressed in cells of placental extravillous cytotrophoblast (Langhans' layer), amnios epithelial cells, fetal endothelial cells, mesenchymal macrophages of chorionic villi, and in epithelial cells of thymus medulla; the second ones in amniotic fluid, in maternal peripheral blood and that of the umbilical cord. There was a HLA-G expression in some types of tumors, stroma cells under inflammation conditions, virus-infected cells and in serum of transplant patients. There are strong evidences of HLA-G molecules role in tolerance induction to these physiological and pathological situations through suppression of lithic activity of NK cells and of cytotoxic T lymphocytes. This knowledge may be very useful in future therapeutical management of these entities as well as to favor the success of tissue and organ transplant

Donor-derived HLA antibody production in patients undergoing SCT from HLA antibody-positive donors.

Science.gov (United States)

Taniguchi, K; Yoshihara, S; Maruya, E; Ikegame, K; Kaida, K; Hayashi, K; Kato, R; Inoue, T; Fujioka, T; Tamaki, H; Okada, M; Onuma, T; Fujii, N; Kusunoki, Y; Soma, T; Saji, H; Ogawa, H

2012-10-01

Pre-existing donor-specific HLA antibodies in patients undergoing HLA-mismatched SCT have increasingly been recognized as a risk factor for primary graft failure. However, the clinical implications of the presence of HLA antibodies in donors remain unknown. We prospectively examined 123 related donors for the presence of HLA antibodies by using a Luminex-based single antigen assay. Of these, 1/57 (1.8%) male, 6/27 (22%) parous female and 0/39 (0%) nonparous female donors were HLA antibody-positive. Then, we determined the presence of HLA antibodies in seven patients who received SCT from antibody-positive donors. Of these, four became HLA antibody-positive after SCT. The specificities of the antibodies that emerged in the patients closely resembled those of the antibodies found in the donors, indicating their production by donor-derived plasma cells. Moreover, the kinetics of the HLA antibody levels were similar in all four patients: levels started increasing within 1 week after SCT and peaked at days 10-21, followed by a gradual decrease. These results suggest that donor-derived HLA antibody production frequently occurs in patients undergoing SCT from antibody-positive donors. Further studies are warranted for clarifying the clinical significance of donor-derived HLA antibodies, including the role of these antibodies in post transplant platelet transfusion refractoriness.

Impact of HLA Diversity on Donor Selection in Organ and Stem Cell Transplantation

OpenAIRE

Tiercy Jean-Marie; Claas Frans

2013-01-01

The human major histocompatibility complex is a multigene system encoding polymorphic human leucocyte antigens (HLA) that present peptides derived from pathogens to the immune system. The high diversity of HLA alleles and haplotypes in the worldwide populations represents a major barrier to organ and allogeneic hematopoietic stem cell transplantation because HLA incompatibilities are efficiently recognized by T and B lymphocytes. In organ transplantation pre transplant anti HLA antibodies nee...

Production of human anti-HLA monoclonal antibodies

Energy Technology Data Exchange (ETDEWEB)

Walker, M.C.; Mercier, F.; Roger, J.; Varin, M.

1986-03-01

Only 40% of the several hundred anti-HLA murine monoclonal antibodies (MAbs) that have been made detect HLA-A,B,C or DR specificities previously defined by human alloantisera, the range of recognized specificities is very narrow, and few of the MAbs have proven useful as tissue typing reagents. In hopes of obtaining HLA typing reagents, the authors are developing a protocol for the production of human anti-HLA MAbs from HLA-antigen (Ag) immunized peripheral blood B cells of volunteering renal patients, immunized to one or more HLA Ags through therapeutic blood transfusions. A simple enrichment of the donor B cells has not been sufficient for anti-HLA MAb production, the authors are currently delineating the conditions necessary for increasing the number of HLA-specific donor B cells by in vitro stimulation with cells expressing the HLA Ag to which the B cell donor is immunized. For the production of MAbs, the stimulated B cells are transformed with Epstein-Barr virus and subsequently fused with KR-4 lymphoblastoid cells. Hybridomas are selected by HAT and Ouabain. Supernatants are screened for anti-HLA activity against lymphocyte targets expressing the original immunizing HLA Ag by complement mediated /sup 51/Cr release assay. Antibody specificity is determined by the complement-dependent microcytotoxicity test used for HLA typing.

B cell repertoires in HLA-sensitized kidney transplant candidates undergoing desensitization therapy.

Science.gov (United States)

Beausang, John F; Fan, H Christina; Sit, Rene; Hutchins, Maria U; Jirage, Kshama; Curtis, Rachael; Hutchins, Edward; Quake, Stephen R; Yabu, Julie M

2017-01-13

Kidney transplantation is the most effective treatment for end-stage renal disease. Sensitization refers to pre-existing antibodies against human leukocyte antigen (HLA) protein and remains a major barrier to successful transplantation. Despite implementation of desensitization strategies, many candidates fail to respond. Our objective was to determine whether measuring B cell repertoires could differentiate candidates that respond to desensitization therapy. We developed an assay based on high-throughput DNA sequencing of the variable domain of the heavy chain of immunoglobulin genes to measure changes in B cell repertoires in 19 highly HLA-sensitized kidney transplant candidates undergoing desensitization and 7 controls with low to moderate HLA sensitization levels. Responders to desensitization had a decrease of 5% points or greater in cumulated calculated panel reactive antibody (cPRA) levels, and non-responders had no decrease in cPRA. Dominant B cell clones were not observed in highly sensitized candidates, suggesting that the B cells responsible for sensitization are either not present in peripheral blood or present at comparable levels to other circulating B cells. Candidates that responded to desensitization therapy had pre-treatment repertoires composed of a larger fraction of class-switched (IgG and IgA) isotypes compared to non-responding candidates. After B cell depleting therapy, the proportion of switched isotypes increased and the mutation frequencies of the remaining non-switched isotypes (IgM and IgD) increased in both responders and non-responders, perhaps representing a shift in the repertoire towards memory B cells or plasmablasts. Conversely, after transplantation, non-switched isotypes with fewer mutations increased, suggesting a shift in the repertoire towards naïve B cells. Relative abundance of different B cell isotypes is strongly perturbed by desensitization therapy and transplantation, potentially reflecting changes in the relative

Activated allogeneic NK cells preferentially kill poor prognosis B-cell chronic lymphocytic leukemia cells

Directory of Open Access Journals (Sweden)

Diego Sanchez-Martinez

2016-10-01

Full Text Available Mutational status of TP53 together with expression of wild type (wt IGHV represents the most widely accepted biomarkers, establishing a very poor prognosis in B-cell chronic lymphocytic leukemia (B-CLL patients. Adoptive cell therapy using allogeneic HLA mismatched Natural Killer (NK cells has emerged as an effective and safe alternative in the treatment of acute myeloid and lymphoid leukemias that do not respond to traditional therapies. We have described that allogeneic activated NK cells eliminate hematological cancer cell lines with multidrug resistance acquired by mutations in the apoptotic machinery. This effect depends on the activation protocol, being B-lymphoblastoid cell lines (LCLs the most effective stimulus to activate NK cells. Here we have further analyzed the molecular determinants involved in allogeneic NK cell recognition and elimination of B-CLL cells, including the expression of ligands of the main NK cell activating receptors (NKG2D and NCRs and HLA mismatch. We present preliminary data suggesting that B-CLL susceptibility significantly correlates with HLA mismatch between NK cell donor and B-CLL patient. Moreover, we show that the sensitivity of B-CLL cells to NK cells depends on the prognosis based on TP53 and IGHV mutational status. Cells from patients with worse prognosis (mutated TP53 and wt IGHV are the most susceptible to activated NK cells. Hence, B-CLL prognosis may predict the efficacy of allogenic activated NK cells and, thus, NK cell transfer represents a good alternative to treat poor prognosis B-CLL patients who present a very short life expectancy due to lack of effective treatments.□

Polymorphism in the 5' upstream regulatory and 3' untranslated regions of the HLA-G gene in relation to soluble HLA-G and IL-10 expression

DEFF Research Database (Denmark)

Hviid, Thomas Vauvert F; Rizzo, Roberta; Melchiorri, Loredana

2006-01-01

The nonclassical human leukocyte antigen (HLA) class Ib gene HLA-G may be important for the induction and maintenance of immune tolerance between the mother and the semi-allogeneic fetus during pregnancy. Expression of HLA-G can influence cytokine and cytotoxic T-lymphocyte responses. Different HLA......-G peripheral blood mononuclear cells after lipopolysaccharide (LPS) stimulation. This study finds that polymorphism in the 5' upstream regulatory region (5'URR) of the HLA-G gene may also be implicated in differences in IL-10 secretion. However, this may also be due to linkage disequilibrium with the 14-bp...

HLA Class I Binding 9mer Peptides from Influenza A Virus Induce CD4(+) T Cell Responses

DEFF Research Database (Denmark)

Wang, M. J.; Larsen, Mette Voldby; Nielsen, Morten

2010-01-01

of the pan-specific anti-HLA class II (HLA-II) antibody IVA12. Blocking of HLA-II subtype reactivity revealed that 8 and 6 peptide responses were blocked by anti-HLA-DR and -DP antibodies, respectively. Peptide reactivity of PBMC depleted of CD4(+) or CD8(+) T cells prior to the ELISPOT culture revealed...... that effectors are either CD4(+) (the majority of reactivities) or CD8(+) T cells, never a mixture of these subsets. Three of the peptides, recognized by CD4(+) T cells showed binding to recombinant DRA1*0101/DRB1*0401 or DRA1*0101/DRB5*0101 molecules in a recently developed biochemical assay. Conclusions....../Significance: HLA-I binding 9mer influenza virus-derived peptides induce in many cases CD4(+) T cell responses restricted by HLA-II molecules....

Evaluation of gene delivery strategies to efficiently overexpress functional HLA-G on human bone marrow stromal cells

Directory of Open Access Journals (Sweden)

Joana S Boura

2014-01-01

Full Text Available Mesenchymal stromal cells (MSC constitutively express low levels of human leukocyte antigen-G (HLA-G, which has been shown to contribute to their immunomodulatory and anti-inflammatory properties. Here, we hypothesized that overexpression of HLA-G on bone marrow-derived MSC would improve their immunomodulatory function, thus increasing their therapeutic potential. Therefore, we investigated which gene transfer system is best suited for delivering this molecule while maintaining its immunomodulatory effects. We performed a side-by-side comparison between three nonviral plasmid-based platforms (pmax-HLA-G1; MC-HLA-G1; pEP-HLA-G1 and a viral system (Lv-HLA-G1 using gene transfer parameters that yielded similar levels of HLA-G1-expressing MSC. Natural killer (NK cell–mediated lysis assays and T cell proliferation assays showed that MSC modified with the HLA-G1 expressing viral vector had significantly lower susceptibility to NK-lysis and significantly reduced T cell proliferation when compared to nonmodified cells or MSC modified with plasmid. We also show that, in plasmid-modified MSC, an increase in Toll-like receptor (TLR9 expression is the mechanism responsible for the abrogation of HLA-G1's immunomodulatory effect. Although MSC can be efficiently modified to overexpress HLA-G1 using viral and nonviral strategies, only viral-based delivery of HLA-G1 is suitable for improvement of MSC's immunomodulatory properties.

Allelic imbalance modulates surface expression of the tolerance-inducing HLA-G molecule on primary trophoblast cells

DEFF Research Database (Denmark)

Djurisic, S; Teiblum, S; Tolstrup, C K

2015-01-01

The HLA-G molecule is expressed on trophoblast cells at the feto-maternal interface, where it interacts with local immune cells, and upholds tolerance against the semi-allogeneic fetus. Aberrant HLA-G expression in the placenta and reduced soluble HLA-G levels are observed in pregnancy complicati...

Establishment of HLA-DR4 transgenic mice for the identification of CD4+ T cell epitopes of tumor-associated antigens.

Directory of Open Access Journals (Sweden)

Junji Yatsuda

Full Text Available Reports have shown that activation of tumor-specific CD4(+ helper T (Th cells is crucial for effective anti-tumor immunity and identification of Th-cell epitopes is critical for peptide vaccine-based cancer immunotherapy. Although computer algorithms are available to predict peptides with high binding affinity to a specific HLA class II molecule, the ability of those peptides to induce Th-cell responses must be evaluated. We have established HLA-DR4 (HLA-DRA*01:01/HLA-DRB1*04:05 transgenic mice (Tgm, since this HLA-DR allele is most frequent (13.6% in Japanese population, to evaluate HLA-DR4-restricted Th-cell responses to tumor-associated antigen (TAA-derived peptides predicted to bind to HLA-DR4. To avoid weak binding between mouse CD4 and HLA-DR4, Tgm were designed to express chimeric HLA-DR4/I-E(d, where I-E(d α1 and β1 domains were replaced with those from HLA-DR4. Th cells isolated from Tgm immunized with adjuvant and HLA-DR4-binding cytomegalovirus-derived peptide proliferated when stimulated with peptide-pulsed HLA-DR4-transduced mouse L cells, indicating chimeric HLA-DR4/I-E(d has equivalent antigen presenting capacity to HLA-DR4. Immunization with CDCA155-78 peptide, a computer algorithm-predicted HLA-DR4-binding peptide derived from TAA CDCA1, successfully induced Th-cell responses in Tgm, while immunization of HLA-DR4-binding Wilms' tumor 1 antigen-derived peptide with identical amino acid sequence to mouse ortholog failed. This was overcome by using peptide-pulsed syngeneic bone marrow-derived dendritic cells (BM-DC followed by immunization with peptide/CFA booster. BM-DC-based immunization of KIF20A494-517 peptide from another TAA KIF20A, with an almost identical HLA-binding core amino acid sequence to mouse ortholog, successfully induced Th-cell responses in Tgm. Notably, both CDCA155-78 and KIF20A494-517 peptides induced human Th-cell responses in PBMCs from HLA-DR4-positive donors. Finally, an HLA-DR4 binding DEPDC1191

The effect of progesterone and 17-β estradiol on membrane-bound HLA-G in adipose derived stem cells.

Science.gov (United States)

Moslehi, Akram; Hashemi-Beni, Batool; Moslehi, Azam; Akbari, Maryam Ali; Adib, Minoo

2016-07-01

Membrane-bound HLA-G (mHLA-G) discovery on adipose derived stem cells (ADSCs) as a tolerogenic and immunosuppressive molecule was very important. Many documents have shown that HLA-G expression can be controlled via some hormones such as progesterone (P4) and estradiol (E2). Therefore, this study was designed to evaluate progesterone and estradiol effects on mHLA-G in ADSCs at restricted and combination concentrations. Three independent cell lines were cultured in complete free phenol red DMEM and subcultured to achieve suffi cient cells. These cells were treated with P4, E2 and P4 plus E2 at physiologic and pregnancy concentrations for 3 days in cell culture conditions. The HLA-G positive ADSCs was measured via monoclonal anti HLA-G-FITC/MEMG-09 by means of flow cytometry in nine groups. Data were analyzed by one way ANOVA and Tukey's post hoc tests. There were no signifi cant values of the mean percentage of HLA-G positive cells in E2-treated and the combination of P4 plus E2-treated ADSCs compared to control cells (p value>0.05) but P4 had a signifi cant increase on mHLA-G in ADSCs (p value<0.05). High P4 concentration increased mHLA-G but E2 and the combination of P4 plus E2 could not change mHLA-G on ADSCs.

Denaturation of membrane proteins and hyperthermic cell killing

NARCIS (Netherlands)

Burgman, Paulus Wilhelmus Johannes Jozef

1993-01-01

Summarizing: heat induced denaturation of membrane proteins is probably related to hyperthermic cell killing. Induced resistance of heat sensitive proteins seems to be involved in the development of thermotolerance. Although many questions remain still to be answered, it appears that HSP72, when

Permanent, lowered HLA class I expression using lentivirus vectors with shRNA constructs: Averting cytotoxicity by alloreactive T lymphocytes.

Science.gov (United States)

Haga, K; Lemp, N A; Logg, C R; Nagashima, J; Faure-Kumar, E; Gomez, G G; Kruse, C A; Mendez, R; Stripecke, R; Kasahara, N; Kasahara, N A; Cicciarelli, J C

2006-12-01

Transplantation of many tissues requires histocompatibility matching of human leukocyte antigens (HLA) to prevent graft rejection, to reduce the level of immunosuppression needed to maintain graft survival, and to minimize the risk of graft-versus-host disease, particularly in the case of bone marrow transplantation. However, recent advances in fields of gene delivery and genetic regulation technologies have opened the possibility of engineering grafts that display reduced levels of HLA expression. Suppression of HLA expression could help to overcome the limitations imposed by extensive HLA polymorphisms that restrict the availability of suitable donors, necessitate the maintenance of large donor registries, and complicate the logistics of procuring and delivering matched tissues and organs to the recipient. Accordingly, we investigated whether knockdown of HLA by RNA interference (RNAi), a ubiquitous regulatory system that can efficiently and selectively inhibit the expression of specific gene products, would enable allogeneic cells to evade immune recognition. For efficient and stable delivery of short hairpin-type RNAi constructs (shRNA), we employed lentivirus-based gene transfer vectors, which provide a delivery system that can achieve integration into genomic DNA, thereby permanently modifying transduced graft cells. Our results show that lentivirus-mediated delivery of shRNA targeting pan-Class I and allele-specific HLA can achieve efficient and dose-dependent reduction in surface expression of HLA in human cells, associated with enhanced resistance to alloreactive T lymphocyte-mediated cytotoxicity, while avoiding MHC-non-restricted killing. We hypothesize that RNAi-induced silencing of HLA expression has the potential to create histocompatibility-enhanced, and, eventually, perhaps "universally" compatible cellular grafts.

The Escape of Cancer from T Cell-Mediated Immune Surveillance: HLA Class I Loss and Tumor Tissue Architecture

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Federico Garrido

2017-02-01

Full Text Available Tumor immune escape is associated with the loss of tumor HLA class I (HLA-I expression commonly found in malignant cells. Accumulating evidence suggests that the efficacy of immunotherapy depends on the expression levels of HLA class I molecules on tumors cells. It also depends on the molecular mechanism underlying the loss of HLA expression, which could be reversible/“soft” or irreversible/“hard” due to genetic alterations in HLA, β2-microglobulin or IFN genes. Immune selection of HLA-I negative tumor cells harboring structural/irreversible alterations has been demonstrated after immunotherapy in cancer patients and in experimental cancer models. Here, we summarize recent findings indicating that tumor HLA-I loss also correlates with a reduced intra-tumor T cell infiltration and with a specific reorganization of tumor tissue. T cell immune selection of HLA-I negative tumors results in a clear separation between the stroma and the tumor parenchyma with leucocytes, macrophages and other mononuclear cells restrained outside the tumor mass. Better understanding of the structural and functional changes taking place in the tumor microenvironment may help to overcome cancer immune escape and improve the efficacy of different immunotherapeutic strategies. We also underline the urgent need for designing strategies to enhance tumor HLA class I expression that could improve tumor rejection by cytotoxic T-lymphocytes (CTL.

Allelic imbalance modulates surface expression of the tolerance-inducing HLA-G molecule on primary trophoblast cells.

Science.gov (United States)

Djurisic, S; Teiblum, S; Tolstrup, C K; Christiansen, O B; Hviid, T V F

2015-03-01

The HLA-G molecule is expressed on trophoblast cells at the feto-maternal interface, where it interacts with local immune cells, and upholds tolerance against the semi-allogeneic fetus. Aberrant HLA-G expression in the placenta and reduced soluble HLA-G levels are observed in pregnancy complications, partly explained by HLA-G polymorphisms which are associated with differences in the alternative splicing pattern and of the stability of HLA-G mRNA. Of special importance is a 14 bp insertion/deletion polymorphism located in the 3'-untranslated region of the HLA-G gene. In the current study, we present novel evidence for allelic imbalance of the 14 bp insertion/deletion polymorphism, using a very accurate and sensitive Digital droplet PCR technique. Allelic imbalance in heterozygous samples was observed as differential expression levels of 14 bp insertion/deletion allele-specific mRNA transcripts, which was further associated with low levels of HLA-G surface expression on primary trophoblast cells. Full gene sequencing of HLA-G allowed us to study correlations between HLA-G extended haplotypes and single-nucleotide polymorphisms and HLA-G surface expression. We found that a 1:1 expression (allelic balance) of the 14 bp insertion/deletion mRNA alleles was associated with high surface expression of HLA-G and with a specific HLA-G extended haplotype. The 14 bp del/del genotype was associated with a significantly lower abundance of the G1 mRNA isoform, and a higher abundance of the G3 mRNA isoform. Overall, the present study provides original evidence for allelic imbalance of the 14 bp insertion/deletion polymorphism, which influences HLA-G surface expression on primary trophoblast cells, considered to be important in the pathogenesis of pre-eclampsia and other pregnancy complications. © The Author 2014. Published by Oxford University Press on behalf of the European Society of Human Reproduction and Embryology. All rights reserved. For Permissions, please email: journals.permissions@oup.com.

HLA-G allelic variants are associated with differences in the HLA-G mRNA isoform profile and HLA-G mRNA levels

DEFF Research Database (Denmark)

Hviid, Thomas Vauvert F; Hylenius, Sine; Rørbye, Christina

2003-01-01

between mother and fetus in several ways. Finally, the expression of membrane-bound HLA-G and soluble HLA-G has been proposed to influence the outcome of pregnancy, and an aberrant HLA-G expression in pre-eclamptic placentas and spontaneous abortions has been reported. Here, an association between certain...... HLA-G polymorphisms and the mRNA levels of the different alternatively spliced HLA-G isoforms in first trimester trophoblast cell populations is reported. Several alternatively spliced HLA-G mRNA isoforms, including a 14-bp polymorphism in the 3'UTR end (exon 8) of the HLA-G gene, are expressed...

HLA-G genotype is associated with fetoplacental growth

DEFF Research Database (Denmark)

Hviid, Thomas Vauvert

2004-01-01

The human leukocyte antigen (HLA)-G is expressed by extravillous cytotrophoblast cells in the feto-maternal contact zone. Polymorphisms have been described in the HLA-G gene and have been linked with differences in HLA-G mRNA alternative splicing patterns and protein expression. Differences...... in the isoform profile or the degree of HLA-G expression may influence cytokine production and, thereby, placental and fetal growth. Associations between a 14 bp deletion polymorphism in the 3'UTR part of the HLA-G gene and birth weight in relation to gestational age and placental weight were studied in 47...... pregnancies complicated with preeclampsia and 87 with no preeclampsia. An HLA-G genotype homozygous for the presence of the 14 bp sequence polymorphism was significantly associated with increased birth weight in relation to gestational age (one-way analysis of variance; 2 degrees of freedom: p = 0...

Gene Map of the HLA Region, Graves' Disease and Hashimoto Thyroiditis, and Hematopoietic Stem Cell Transplantation.

Science.gov (United States)

Sasazuki, Takehiko; Inoko, Hidetoshi; Morishima, Satoko; Morishima, Yasuo

2016-01-01

The human leukocyte antigen (HLA) genomic region spanning about 4 Mb is the most gene dense and the polymorphic stretches in the human genome. A total of the 269 loci were identified, including 145 protein coding genes mostly important for immunity and 50 noncoding RNAs (ncRNAs). Biological function of these ncRNAs remains unknown, becoming hot spot in the studies of HLA-associated diseases. The genomic diversity analysis in the HLA region facilitated by next-generation sequencing will pave the way to molecular understanding of linkage disequilibrium structure, population diversity, histocompatibility in transplantation, and associations with autoimmune diseases. The 4-digit DNA genotyping of HLA for six HLA loci, HLA-A through DP, in the patients with Graves' disease (GD) and Hashimoto thyroiditis (HT) identified six susceptible and three resistant HLA alleles. Their epistatic interactions in controlling the development of these diseases are shown. Four susceptible and one resistant HLA alleles are shared by GD and HT. Two HLA alleles associated with GD or HT control the titers of autoantibodies to thyroid antigens. All these observations led us to propose a new model for the development of GD and HT. Hematopoietic stem cell transplantation from unrelated donor (UR-HSCT) provides a natural experiment to elucidate the role of allogenic HLA molecules in immune response. Large cohort studies using HLA allele and clinical outcome data have elucidated that (1) HLA locus, allele, and haplotype mismatches between donor and patient, (2) specific amino acid substitution at specific positions of HLA molecules, and (3) ethnic background are all responsible for the immunological events related to UR-HSCT including acute graft-versus-host disease (GVHD), chronic GVHD, graft-versus-leukemia (GvL) effect, and graft failure. © 2016 Elsevier Inc. All rights reserved.

HLA-G expression and role in advanced-stage classical Hodgkin lymphoma

Directory of Open Access Journals (Sweden)

G. Caocci

2016-04-01

Full Text Available Non-classical human leucocyte antigen (HLA-G class I molecules have an important role in tumor immune escape mechanisms. We investigated HLA-G expression in lymphonode biopsies taken from 8 controls and 20 patients with advanced-stage classical Hodgkin lymphoma (cHL, in relationship to clinical outcomes and the HLA-G 14-basepair (14-bp deletion-insertion (del-ins polymorphism. Lymphnode tissue sections were stained using a specific murine monoclonal HLA-G antibody. HLA-G protein expression was higher in cHL patients than controls. In the group of PET-2 positive (positron emission tomography carried out after 2 cycles of standard chemotherapy patients with a 2-year progression-free survival rate (PFS of 40%, we observed high HLA-G protein expression within the tumor microenvironment with low expression on Hodgkin and Reed-Sternberg (HRS cells. Conversely, PET-2 negative patients with a PFS of 86% had higher HLA-G protein expression levels on HRS cells compared to the microenvironment. Lower expression on HRS cells was significantly associated with the HLA-G 14-bp ins/ins genotype. These preliminary data suggest that the immunohistochemical pattern of HLA-G protein expression may represent a useful tool for a tailored therapy in patients with cHL, based on the modulation of HLA-G expression in relation to achievement of negative PET-2.These preliminary data suggest that the immunohistochemical pattern of HLA-G protein expression may represent a useful tool for a tailored therapy in patients with cHL, based on the modulation of HLA-G expression in relation to achievement of negative PET-2.

Low Constitutive Cell Surface Expression of HLA-B Is Caused by a Posttranslational Mechanism Involving Glu180 and Arg239

DEFF Research Database (Denmark)

Dellgren, Christoffer; Ekwelum, Vanessa A. C.; Ormhøj, Maria

2016-01-01

HLA class I cell surface expression is crucial for normal immune responses, and variability in HLA expression may influence the course of infections. We have previously shown that classical HLA class I expression on many human cell types is biased with greatly reduced expression of HLA-B compared...... by affecting HLA processing in the Ag presentation pathway....

HIV-1 Control by NK Cells via Reduced Interaction between KIR2DL2 and HLA-C∗12:02/C∗14:03.

Science.gov (United States)

Lin, Zhansong; Kuroki, Kimiko; Kuse, Nozomi; Sun, Xiaoming; Akahoshi, Tomohiro; Qi, Ying; Chikata, Takayuki; Naruto, Takuya; Koyanagi, Madoka; Murakoshi, Hayato; Gatanaga, Hiroyuki; Oka, Shinichi; Carrington, Mary; Maenaka, Katsumi; Takiguchi, Masafumi

2016-11-22

Natural killer (NK) cells control viral infection in part through the interaction between killer cell immunoglobulin-like receptors (KIRs) and their human leukocyte antigen (HLA) ligands. We investigated 504 anti-retroviral (ART)-free Japanese patients chronically infected with HIV-1 and identified two KIR/HLA combinations, KIR2DL2/HLA-C ∗ 12:02 and KIR2DL2/HLA-C ∗ 14:03, that impact suppression of HIV-1 replication. KIR2DL2 + NK cells suppressed viral replication in HLA-C ∗ 14:03 + or HLA-C ∗ 12:02 + cells to a significantly greater extent than did KIR2DL2 - NK cells in vitro. Functional analysis showed that the binding between HIV-1-derived peptide and HLA-C ∗ 14:03 or HLA-C ∗ 12:02 influenced KIR2DL2 + NK cell activity through reduced expression of the peptide-HLA (pHLA) complex on the cell surface (i.e., reduced KIR2DL2 ligand expression), rather than through reduced binding affinity of KIR2DL2 to the respective pHLA complexes. Thus, KIR2DL2/HLA-C ∗ 12:02 and KIR2DL2/HLA-C ∗ 14:03 compound genotypes have protective effects on control of HIV-1 through a mechanism involving KIR2DL2-mediated NK cell recognition of virus-infected cells, providing additional understanding of NK cells in HIV-1 infection. Copyright © 2016 The Author(s). Published by Elsevier Inc. All rights reserved.

HLA-D: The T Cell Perspective

Science.gov (United States)

1985-01-01

offspring of consanguineous marriage, in which case the cells are almost always homosygous for all HLA-region products; in other cases, HTCs are...story. Certain relationships exist between the class II serologically defined (I&) and T lymphocyte defined (Dw/LD) specificities. One speaks of one...DRwI4 specificities; in addition, certain of the DRI-DRwl4 specificities are supertypic to the various Dw specificities. The relationships of these

Direct ex vivo detection of HLA-DR3-restricted cytomegalovirus- and Mycobacterium tuberculosis-specific CD4+ T cells.

Science.gov (United States)

Bronke, Corine; Palmer, Nanette M; Westerlaken, Geertje H A; Toebes, Mireille; van Schijndel, Gijs M W; Purwaha, Veenu; van Meijgaarden, Krista E; Schumacher, Ton N M; van Baarle, Debbie; Tesselaar, Kiki; Geluk, Annemieke

2005-09-01

In order to detect epitope-specific CD4+ T cells in mycobacterial or viral infections in the context of human class II major histocompatibility complex protein human leukocyte antigen (HLA)-DR3, two HLA-DR3 tetrameric molecules were successfully produced. One contained an immunodominant HLA-DR3-restricted T-cell epitope derived from the 65-kDa heat-shock protein of Mycobacterium tuberculosis, peptide 1-13. For the other tetramer, we used an HLA-DR3-restricted T-cell epitope derived from cytomegalovirus (CMV) pp65 lower matrix protein, peptide 510-522, which induced high levels of interferon (IFN)-gamma-producing CD4+ T cells in three of four HLA-DR3-positive CMV-seropositive individuals up to 0.84% of CD4+ T cells by intracellular cytokine staining. In peripheral blood mononuclear cells from M. tuberculosis-exposed, Mycobacterium bovis bacille Calmette-Guérin (BCG)-vaccinated, or CMV-seropositive individuals, we were able to directly detect with both tetramers epitope-specific T cells up to 0.62% and 0.45% of the CD4+ T-cell population reactive to M. tuberculosis and CMV, respectively. After a 6-day culture with peptide p510-522, the frequency of CMV-specific tetramer-binding T cells was expanded up to 9.90% tetramer+ CFSElow (5,6-carboxyfluorescein diacetate succinimidyl ester) cells within the CD4+ T-cell population, further confirming the specificity of the tetrameric molecules. Thus, HLA-DR3/peptide tetrameric molecules can be used to investigate HLA-DR3-restricted antigen-specific CD4+ T cells in clinical disease or after vaccination.

Targetless T cells in cancer immunotherapy

DEFF Research Database (Denmark)

thor Straten, Eivind Per; Garrido, Federico

2016-01-01

Attention has recently focused on new cancer immunotherapy protocols aiming to activate T cell mediated anti-tumor responses. To this end, administration of antibodies that target inhibitory molecules regulating T-cell cytotoxicity has achieved impressive clinical responses, as has adoptive cell...... infiltrate tumor tissues and destroy HLA class I positive tumor cells expressing the specific antigen. In fact, current progress in the field of cancer immune therapy is based on the capacity of T cells to kill cancer cells that present tumor antigen in the context on an HLA class I molecule. However......, it is also well established that cancer cells are often characterized by loss or down regulation of HLA class I molecules, documented in a variety of human tumors. Consequently, immune therapy building on CD8 T cells will be futile in patients harboring HLA class-I negative or deficient cancer cells...

Protective Effect of HLA-B*5701 and HLA-C -35 Genetic Variants in HIV-Positive Caucasians from Northern Poland.

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Magdalena Leszczyszyn-Pynka

Full Text Available Association of two HLA class I variants with HIV-1 pretreatment viremia, CD4+ T cell count at the care-entry and CD4+ T cell nadir.414 HIV-positive Caucasians (30% women aged 19-73 years were genotyped for HLA-C -35 (rs9264942 and HLA-B*5701 variants. HIV-1 viral load, as well as CD4+ T cell count at care-entry and nadir, were compared across alleles, genotypes and haplotypes.HLA-C -35 C/C genotype was found in 17.6% patients, C/T genotype in 48.1%, and T/T genotype in 34.3% patients. HLA-B*5701 variant was present in 5.8% of studied population. HIV plasma viremia in the group with C allele was significantly lower (p=0.0002 compared to T/T group [mean:4.66 log (SD:1.03 vs. 5.07 (SD:0.85 log HIV-RNA copies/ml, respectively], while CD4+ T cell count at baseline was notably higher among C allele carriers compared to T/T homozygotes [median: 318 (IQR:127-537 cells/μl vs. median: 203 (IQR:55-410 cells/μl, respectively] (p=0.0007. Moreover, CD4+ T cell nadir among patients with C allele [median: 205 (IQR:83.5-390 cells/μl] was significantly higher compared to T/T group [median: 133 (IQR:46-328 cells/μl] (p=0.006. Among cases with HLA-B*5701 allele, significantly lower pretreatment viremia and higher baseline CD4+ T cell count were found (mean: 4.08 [SD: 1.2] vs. mean: 4.84 [SD:0.97] log HIV-RNA copies/ml, p=0.003 and 431 vs. 270 cells/μl, p=0.04, respectively compared to HLA-B*5701 negative individuals. The lowest viremia (mean: 3.85 log [SD:1.3] HIV-RNA copies/ml and the highest baseline and nadir CD4+ T cell [median: 476 (IQR:304-682 vs. median: 361 (IQR: 205-574 cells/μl, respectively were found in individuals with HLA-B*5701(+/HLA-C -35 C/C haplotype.HLA-C -35 C and HLA-B*5701 allele exert a favorable effect on the immunological (higher baseline and nadir CD4+ T cell count and virologic (lower pretreatment HIV viral load variables. This protective effect is additive for the compound HLA-B*5701(+/HLA-C -35 C/C haplotype.

Upregulation of HLA Class I Expression on Tumor Cells by the Anti-EGFR Antibody Nimotuzumab

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Greta Garrido

2017-10-01

Full Text Available Defining how epidermal growth factor receptor (EGFR-targeting therapies influence the immune response is essential to increase their clinical efficacy. A growing emphasis is being placed on immune regulator genes that govern tumor – T cell interactions. Previous studies showed an increase in HLA class I cell surface expression in tumor cell lines treated with anti-EGFR agents. In particular, earlier studies of the anti-EGFR blocking antibody cetuximab, have suggested that increased tumor expression of HLA class I is associated with positive clinical response. We investigated the effect of another commercially available anti-EGFR antibody nimotuzumab on HLA class I expression in tumor cell lines. We observed, for the first time, that nimotuzumab increases HLA class I expression and its effect is associated with a coordinated increase in mRNA levels of the principal antigen processing and presentation components. Moreover, using 7A7 (a specific surrogate antibody against murine EGFR, we obtained results suggesting the importance of the increased MHC-I expression induced by EGFR-targeted therapies display higher in antitumor immune response. 7A7 therapy induced upregulation of tumor MHC-I expression in vivo and tumors treated with this antibody display higher susceptibility to CD8+ T cells-mediated lysis. Our results represent the first evidence suggesting the importance of the adaptive immunity in nimotuzumab-mediated antitumor activity. More experiments should be conducted in order to elucidate the relevance of this mechanism in cancer patients. This novel immune-related antitumor mechanism mediated by nimotuzumab opens new perspectives for its combination with various immunotherapeutic agents and cancer vaccines.

Peptide immunisation of HLA-DR-transgenic mice permits the identification of a novel HLA-DRbeta1*0101- and HLA-DRbeta1*0401-restricted epitope from p53.

Science.gov (United States)

Rojas, José Manuel; McArdle, Stephanie E B; Horton, Roger B V; Bell, Matthew; Mian, Shahid; Li, Geng; Ali, Selman A; Rees, Robert C

2005-03-01

Because of the central role of CD4(+) T cells in antitumour immunity, the identification of the MHC class II-restricted peptides to which CD4(+) T cells respond has become a priority of tumour immunologists. Here, we describe a strategy permitting us to rapidly determine the immunogenicity of candidate HLA-DR-restricted peptides using peptide immunisation of HLA-DR-transgenic mice, followed by assessment of the response in vitro. This strategy was successfully applied to the reported haemaglutinin influenza peptide HA(307-319), and then extended to three candidate HLA-DR-restricted p53 peptides predicted by the evidence-based algorithm SYFPEITHI to bind to HLA-DRbeta1*0101 (HLA-DR1) and HLA-DRbeta1*0401 (HLA-DR4) molecules. One of these peptides, p53(108-122), consistently induced responses in HLA-DR1- and in HLA-DR4-transgenic mice. Moreover, this peptide was naturally processed by dendritic cells (DCs), and induced specific proliferation in the splenocytes of mice immunised with p53 cDNA, demonstrating that immune responses could be naturally mounted to the peptide. Furthermore, p53(108-122) peptide was also immunogenic in HLA-DR1 and HLA-DR4 healthy donors. Thus, the use of this transgenic model permitted the identification of a novel HLA-DR-restricted epitope from p53 and constitutes an attractive approach for the rapid identification of novel immunogenic MHC class II-restricted peptides from tumour antigens, which can ultimately be incorporated in immunotherapeutic protocols.

The role of HLA-E polymorphism in immunological response

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Milena Iwaszko

2011-09-01

Full Text Available The HLA-E protein is one of the most extensively studied MHC class Ib antigens and the least polymorphic one compared to other MHC class I molecules. In the human population there have been reported just ten alleles encoding three different peptides. Only two of these alleles, namely HLA-E*0101 and HLA-E*0103, are widely distributed (around 50�0each. The proteins encoded by these alleles differ from each other in one amino acid at position 107. In HLA-E*0101 it is arginine and in HLA-E*0103 it is glycine. The difference between these proteins manifests itself in surface expression levels, affinities to leader peptides and thermal stabilities of their complexes.The HLA-E molecule is a ligand for CD94/NKG2 receptors on NK cells and TCR receptors on NK-CTL (NK-cytotoxic T lymphocyte cells, so it plays a double role in both innate and adaptive immunity. This paper reviews the knowledge on the role of the HLA-E molecule in the immunological response. Aspects related to polymorphism of the HLA-E gene and the course of several diseases including type I diabetes, ankylosing spondylitis, HCV and HIV infections, nasopharyngeal cancer and recurrent spontaneous abortions, as well as the outcome of hematopoietic stem cell transplantation, are presented and discussed in more detail.

Specific central nervous system recruitment of HLA-G(+) regulatory T cells in multiple sclerosis.

Science.gov (United States)

Huang, Yu-Hwa; Zozulya, Alla L; Weidenfeller, Christian; Metz, Imke; Buck, Dorothea; Toyka, Klaus V; Brück, Wolfgang; Wiendl, Heinz

2009-08-01

We have recently described a novel population of natural regulatory T cells (T(reg)) that are characterized by the expression of HLA-G and may be found at sites of tissue inflammation (HLA-G(pos) T(reg)). Here we studied the role of these cells in multiple sclerosis (MS), a prototypic autoimmune inflammatory disorder of the central nervous system (CNS). Sixty-four patients with different types of MS, 9 patients with other neurological diseases, and 20 healthy donors were included in this study. Inflamed brain lesions from 5 additional untreated MS patients were examined. HLA-G(pos) T(reg) were analyzed in the cerebrospinal fluid (CSF) by flow cytometry and in inflammatory demyelinating lesions of MS brain specimens by immunohistochemistry. Functional capacity was accessed and transmigration was determined using an in vitro model of the human blood-brain barrier (BBB). HLA-G(pos) T(reg) were found enriched in the inflamed CSF of MS patients and in inflammatory demyelinating lesions of MS brain specimens. HLA-G(pos) T(reg) showed a strong propensity to transmigrate across BBB, which was vigorously driven by inflammatory chemokines, and associated with a gain of suppressive capacity upon transmigration. CSF-derived HLA-G(pos) T(reg) of MS patients represented a population of activated central memory activated T cells with an upregulated expression of inflammatory chemokine receptors and exhibiting full suppressive capacity. Unlike natural FoxP3-expressing T(reg), HLA-G(pos) T(reg) derived from peripheral blood were functionally unimpaired in MS. In MS, HLA-G(pos) T(reg) may serve to control potentially destructive immune responses directly at the sites of CNS inflammation and to counterbalance inflammation once specifically recruited to the CNS.

Mechanisms of Enhanced Cell Killing at Low Doses: Implications for Radiation Risk

International Nuclear Information System (INIS)

Johnston, Peter J.; Wilson, George D.

2003-01-01

We have shown that cell lethality actually measured after exposure to low-doses of low-LET radiation, is markedly enhanced relative to the cell lethality previously expected by extrapolation of the high-dose cell-killing response. Net cancer risk is a balance between cell transformation and cell kill and such enhanced lethality may more than compensate for transformation at low radiation doses over a least the first 10 cGy of low-LET exposure. This would lead to a non-linear, threshold, dose-risk relationship. Therefore our data imply the possibility that the adverse effects of small radiation doses (<10 cGy) could be overestimated in specific cases. It is now important to research the mechanisms underlying the phenomenon of low-dose hypersensitivity to cell killing, in order to determine whether this can be generalized to safely allow an increase in radiation exposure limits. This would have major cost-reduction implications for the whole EM program

Recent progress of national banking project on homozygous HLA-typed induced pluripotent stem cells in South Korea.

Science.gov (United States)

Rim, Yeri Alice; Park, Narae; Nam, Yoojun; Ham, Dong-Sik; Kim, Ji-Won; Ha, Hye-Yeong; Jung, Ji-Won; Jung, Seung Min; Baek, In Cheol; Kim, Su-Yeon; Kim, Tai-Gyu; Song, Jihwan; Lee, Jennifer; Park, Sung-Hwan; Chung, Nak-Gyun; Yoon, Kun-Ho; Ju, Ji Hyeon

2018-03-01

Induced pluripotent stem cells (iPSCs) can be generated by introducing several factors into mature somatic cells. Banking of iPSCs can lead to wider application for treatment and research. In an economical view, it is important to store cells that can cover a high percentage of the population. Therefore, the use of homozygous human leukocyte antigen-iPSCs (HLA-iPSCs) is thought as a potential candidate for effective iPSC banking system for further clinical use. We screened the database stored in the Catholic Hematopoietic Stem Cell Bank of Korea and sorted the most frequent homozygous HLA types of the South Korean population. Blood cells with the selected homozygous HLA types were obtained and transferred to the GMP facility in the Catholic Institute of Cell Therapy. Cells were reprogrammed to iPSCs inside the facility and went through several quality controls. As a result, a total of 13 homozygous GMP-grade iPSC lines were obtained in the facility. The generated iPSCs showed high pluripotency and normal karyotype after reprogramming. Five HLA-homozygous iPSCs had the type that was included in the top five most frequent HLA types. Homozygous HLA-iPSCs can open a new opportunity for further application of iPSCs in clinical research and therapy. Copyright © 2017 John Wiley & Sons, Ltd.

HLA-DRB and HLA-DQ genetic variability in patients with aspirin-exacerbated respiratory disease.

Science.gov (United States)

Esmaeilzadeh, Hossein; Nabavi, Mohammad; Amirzargar, Ali Akbar; Aryan, Zahra; Arshi, Saba; Bemanian, Mohammad Hassan; Fallahpour, Morteza; Mortazavi, Negar; Rezaei, Nima

2015-01-01

Major histocompatibility complex (MHC) class II is involved in T-cell activation, cytokine secretion, and induction of immune responses. Cytokines, staphylococcus super antigens, and eosinophil activation are proposed to play important roles in aspirin-exacerbated respiratory disease (AERD). This study is aimed at investigating the association of HLA-DRB and DQ genetic variabilities in patients with AERD. A genetic association analysis in three different groups, including 33 patients with AERD, 17 patients with aspirin-tolerant asthma (ATA), and 100 healthy controls was performed. Oral aspirin challenge (OAC) test was performed to identify aspirin hypersensitivity. Pulmonary function test (PFT) was performed for all patients. Eosinophil percentage in nasal smear and peripheral blood and serum immunoglobin (Ig)E were investigated. HLA-DRB, HLA-DQA1, and HLA-DQB1 were genotyped using polymerase chain reaction. HLA-DQB1*0302 (OR, 5.49, 95% confidence interval [CI],(2.40-12.59)), HLA-DQA1*0301 (OR, 2.90, 95% CI, (1.49-5.67)), HLA-DRB4 (OR, 2.94, 95% CI, (1.61-5.36)), and HLA-DRB1*04 (OR, 3.19, 95% CI, (1.57-6.47)) were higher in patients with AERD compared with controls. In patients with AERD, HLA-DQB1*0301 (OR,0.22, 95% CI, (0.09-0.54)), HLA-DQA1*0501 (OR, 0.42, 95% CI, (0.21-0.81)), HLA-DRB1*11 (OR, 0.30, 95% CI, (0.12-0.73)), and HLA-DRB3 (OR, 0.38, 95% CI, (0.21-0.70)) were significantly lower compared with healthy controls. Patients with AERD had lower frequencies of HLA-DQB1*0301 (OR, 0.27, 95% CI, (0.08-0.86)), and HLA-DRB1*011 (OR, 0.27, 95% CI, (0.08-0.86)) compared with ATA. Haplotypes of HLA-DRB1*04/ DQA1*0301/ DQB1*0302 (OR, 4.25, 95% CI, (1.94-9.29)) and HLA-DRB1*07 /DQA1*0201/ DQB1*0201 (OR, 3.52, 95% CI, (1.54-8.06)) were higher in patients with AERD compared with controls (all p < 0.05). Results of this study suggest that HLA-DQB1*0302 and HLA-DRB1*04 and their related haplotypes are genes involved in predisposing patients to AERD, whereas HLA-DQB1

Homotypic aggregation of human cell lines by HLA class II-, class Ia- and HLA-G-specific monoclonal antibodies

DEFF Research Database (Denmark)

Odum, Niels; Ledbetter, J A; Martin, P

1991-01-01

Major histocompatibility complex (MHC) class II molecules have been implicated in cell adhesion in two ways. In addition to the well-established role of class II antigens in low-affinity adhesion provided by interactions between class II and CD4, recent data indicated that class II may also induce...... adhesion between T and B cells by activating the CD18/CD11a (LFA-1) adhesion pathway. Here we report that monoclonal antibodies (mAb) against HLA-DR (L243, p4.1, HB10a, VI15) and certain broad class II reacting mAb (TU35, TU39), but not anti-DQ (TU22, Leu-10) mAb, induced homotypic aggregation of human...... class II-positive monocytic (I937) and T leukemic (HUT78) tumor cell lines and Epstein-Barr virus (EBV) transformed B-lymphoid cell lines (EBV-LCL). Class II-negative cell lines (U-937 and the EBV-LCL mutant line 616) were not induced to aggregate. An HLA-G-transfected EBV-LCL, 221-AGN...

HLA-G Haplotypes Are Differentially Associated with Asthmatic Features

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Camille Ribeyre

2018-02-01

Full Text Available Human leukocyte antigen (HLA-G, a HLA class Ib molecule, interacts with receptors on lymphocytes such as T cells, B cells, and natural killer cells to influence immune responses. Unlike classical HLA molecules, HLA-G expression is not found on all somatic cells, but restricted to tissue sites, including human bronchial epithelium cells (HBEC. Individual variation in HLA-G expression is linked to its genetic polymorphism and has been associated with many pathological situations such as asthma, which is characterized by epithelium abnormalities and inflammatory cell activation. Studies reported both higher and equivalent soluble HLA-G (sHLA-G expression in different cohorts of asthmatic patients. In particular, we recently described impaired local expression of HLA-G and abnormal profiles for alternatively spliced isoforms in HBEC from asthmatic patients. sHLA-G dosage is challenging because of its many levels of polymorphism (dimerization, association with β2-microglobulin, and alternative splicing, thus many clinical studies focused on HLA-G single-nucleotide polymorphisms as predictive biomarkers, but few analyzed HLA-G haplotypes. Here, we aimed to characterize HLA-G haplotypes and describe their association with asthmatic clinical features and sHLA-G peripheral expression and to describe variations in transcription factor (TF binding sites and alternative splicing sites. HLA-G haplotypes were differentially distributed in 330 healthy and 580 asthmatic individuals. Furthermore, HLA-G haplotypes were associated with asthmatic clinical features showed. However, we did not confirm an association between sHLA-G and genetic, biological, or clinical parameters. HLA-G haplotypes were phylogenetically split into distinct groups, with each group displaying particular variations in TF binding or RNA splicing sites that could reflect differential HLA-G qualitative or quantitative expression, with tissue-dependent specificities. Our results, based on a

Interleukin-15 stimulates natural killer cell-mediated killing of both human pancreatic cancer and stellate cells

Science.gov (United States)

Van Audenaerde, Jonas R.M.; De Waele, Jorrit; Marcq, Elly; Van Loenhout, Jinthe; Lion, Eva; Van den Bergh, Johan M.J.; Jesenofsky, Ralf; Masamune, Atsushi; Roeyen, Geert; Pauwels, Patrick; Lardon, Filip; Peeters, Marc; Smits, Evelien L.J.

2017-01-01

Pancreatic ductal adenocarcinoma (PDAC) is the 4th leading cause of cancer-related death in Western countries with a 5-year survival rate below 5%. One of the hallmarks of this cancer is the strong desmoplastic reaction within the tumor microenvironment (TME), orchestrated by activated pancreatic stellate cells (PSC). This results in a functional and mechanical shield which causes resistance to conventional therapies. Aiming to overcome this resistance by tackling the stromal shield, we assessed for the first time the capacity of IL-15 stimulated natural killer (NK) cells to kill PSC and pancreatic cancer cells (PCC). The potency of IL-15 to promote NK cell-mediated killing was evaluated phenotypically and functionally. In addition, NK cell and immune checkpoint ligands on PSC were charted. We demonstrate that IL-15 activated NK cells kill both PCC and PSC lines (range 9-35% and 20-50%, respectively) in a contact-dependent manner and significantly higher as compared to resting NK cells. Improved killing of these pancreatic cell lines is, at least partly, dependent on IL-15 induced upregulation of TIM-3 and NKG2D. Furthermore, we confirm significant killing of primary PSC by IL-15 activated NK cells in an ex vivo autologous system. Screening for potential targets for immunotherapeutic strategies, we demonstrate surface expression of both inhibitory (PD-L1, PD-L2) and activating (MICA/B, ULBPs and Galectin-9) ligands on primary PSC. These data underscore the therapeutic potential of IL-15 to promote NK cell-mediated cytotoxicity as a treatment of pancreatic cancer and provide promising future targets to tackle remaining PSC. PMID:28915646

HIV transcription is induced with some forms of cell killing

International Nuclear Information System (INIS)

Woloschak, G.E.; Schreck, S.; Chang-Liu, C.-M.; Libertin, C.R.

1996-01-01

Using HeLa cells stably transfected with an HIV-LTR-CAT construct', we demonstrated a peak in CAT induction that occurs in viable (but not necessarily cell-division-competent) cells 24 h following exposure to some cell-killing agents. Γ rays were the only cell-killing agent which did not induce HIV transcription; this can be attributed to the fact that γ-ray-induced apoptotic death requires function p53, which is missing in HeLa cells. For all other agents, HIV-LTR induction was dose-dependent and correlated with the amount of cell killing that occurred in the culture

HLA-DRB1*16-restricted recognition of myeloid cells, including CD34+ CML progenitor cells

NARCIS (Netherlands)

Ebeling, Saskia B.; Ivanov, Roman; Hol, Samantha; Aarts, Tineke I.; Hagenbeek, Anton; Verdonck, Leo F.; Petersen, Eefke J.

2003-01-01

The therapeutic effect of a human leucocyte antigen (HLA)-identical allogeneic stem cell transplantation (allo-SCT) for the treatment of haematological malignancies is mediated partly by the allogeneic T cells that are administered together with the stem cell graft. Chronic myeloid leukaemia (CML)

Preimplantation genetic diagnosis with HLA matching.

Science.gov (United States)

Rechitsky, Svetlana; Kuliev, Anver; Tur-Kaspa, Illan; Morris, Randy; Verlinsky, Yury

2004-08-01

Preimplantation genetic diagnosis (PGD) has recently been offered in combination with HLA typing, which allowed a successful haematopoietic reconstitution in affected siblings with Fanconi anaemia by transplantation of stem cells obtained from the HLA-matched offspring resulting from PGD. This study presents the results of the first PGD practical experience performed in a group of couples at risk for producing children with genetic disorders. These parents also requested preimplantation HLA typing for treating the affected children in the family, who required HLA-matched stem cell transplantation. Using a standard IVF procedure, oocytes or embryos were tested for causative gene mutations simultaneously with HLA alleles, selecting and transferring only those unaffected embryos, which were HLA matched to the affected siblings. The procedure was performed for patients with children affected by Fanconi anaemia (FANC) A and C, different thalassaemia mutations, Wiscott-Aldrich syndrome, X-linked adrenoleukodystrophy, X-linked hyperimmunoglobulin M syndrome and X-linked hypohidrotic ectodermal displasia with immune deficiency. Overall, 46 PGD cycles were performed for 26 couples, resulting in selection and transfer of 50 unaffected HLA-matched embryos in 33 cycles, yielding six HLA-matched clinical pregnancies and the birth of five unaffected HLA-matched children. Despite the controversy of PGD use for HLA typing, the data demonstrate the usefulness of this approach for at-risk couples, not only to avoid the birth of affected children with an inherited disease, but also for having unaffected children who may also be potential HLA-matched donors of stem cells for treatment of affected siblings.

Protease activation involved in resistance of human cells to x-ray cell killing

International Nuclear Information System (INIS)

Zhang, Hong-Chang; Takahashi, Shuji; Karata, Kiyonobu; Kita, Kazuko; Suzuki, Nobuo

2003-01-01

Little is known of proteases that play roles in the early steps of X-ray irradiation response. In the present study, we first searched for proteases whose activity is induced in human RSa-R cells after X-ray irradiation. The activity was identified as fibrinolytic, using 125 I-labeled fibrin as a substrate. Protease samples were prepared by lysation of cells with a buffer containing MEGA-8. RSa-R cells showed an increased level of protease activity 10 min after X-ray (up to 3 Gy) irradiation. We next examined whether this protease inducibility is causally related with the X-ray susceptibility of cells. Leupeptin, a serine-cysteine protease inhibitor, inhibited the protease activity in samples obtained from X-ray-irradiated RSa-R cells. Treatment of RSa-R cells with the inhibitor before and after X-ray irradiation resulted in an increased susceptibility of the cells to X-ray cell killing. However, the treatment of cells with other inhibitors tested did not modulate the X-ray susceptibility. These results suggest that leupeptin-sensitive proteases are involved in the resistance of human cells to X-ray cell killing. (author)

Paternal HLA-C and Maternal Killer-Cell Immunoglobulin-Like Receptor Genotypes in the Development of Autism.

Science.gov (United States)

Gamliel, Moriya; Anderson, Karen L; Ebstein, Richard P; Yirmiya, Nurit; Mankuta, David

2016-01-01

Killer-cell immunoglobulin-like receptors (KIRs) are a family of cell surface proteins found on natural killer cells, which are components of the innate immune system. KIRs recognize MHC class I proteins, mainly HLA-C and are further divided into two groups: short-tailed 2/3DS activating receptors and long-tailed 2/3DL inhibitory receptors. Based on the Barker Hypothesis, the origins of illness can be traced back to embryonic development in the uterus, and since KIR:HLA interaction figures prominently in the maternal-fetal interface, we investigated whether specific KIR:HLA combinations may be found in autism spectrum disorders (ASD) children compared with their healthy parents. This study enrolled 49 ASD children from different Israeli families, and their healthy parents. Among the parents, a higher frequency of HLA-C2 allotypes was found in the fathers, while its corresponding ligand 2DS1 was found in higher percentage in the maternal group. However, such skewing in KIR:HLA frequencies did not appear in the ASD children. Additionally, analysis of "overall activation" indicated higher activation in maternal than in paternal cohorts.

Superantigen and HLA-DR ligation induce phospholipase-C gamma 1 activation in class II+ T cells

DEFF Research Database (Denmark)

Kanner, S B; Odum, Niels; Grosmaire, L

1992-01-01

Bacterial enterotoxin superantigens bind directly to HLA class II molecules (HLA-DR) expressed on both APC and activated human T cells, and simultaneously bind to certain V beta chains of the TCR. In this report, we compared early T cell signaling events in human alloantigen-stimulated T cells when...... activated by HLA-DR ligation through antibody cross-linking or by direct enterotoxin superantigen binding. Both types of stimuli induced tyrosine phosphorylation of phosphatidylinositol-specific phospholipase C gamma 1 (PLC gamma 1) and an increase in intracellular calcium concentration; however......, superantigen-induced signaling was stronger than class II ligation alone. Antibody-mediated ligation of HLA-DR with CD3 resulted in augmented PLC gamma 1 activation and increased calcium mobilization, consistent with a mechanism of superantigen activity through a combination of class II and CD3/Ti signals...

Describing the Peptide Binding Specificity of HLA-C

DEFF Research Database (Denmark)

Rasmussen, Michael; Harndahl, Mikkel Nors; Nielsen, Morten

for 5 HLA-C molecules and for all, but one, molecule we find a high frequency of binders, >70%, among these peptides. To extend the examined peptide space, we use bioinformatic prediction tools to search for additional binders. Finally, we update our prediction tool, NetMHCpan, with the HLA-C affinity......Human leukocyte antigen (HLA) presents peptides to T-cells for immune scrutiny. Whereas HLA-A and -B have been described in great detail, HLA-C has received much less attention. Here, to increase the coverage of HLA-C and the accuracy of the corresponding tools, we have generated HLA-C molecules...... data and show that the predictive performance for HLA-C molecules now is increased to a level comparable withthat of HLA-A and -B. These novel HLA-C molecules and predictors are successfully used to generate HLA-C tetramers and validate HLA-C-restricted T cell responses....

Comparison of two mathematical models for describing heat-induced cell killing

International Nuclear Information System (INIS)

Roti Roti, J.L.; Henle, K.J.

1980-01-01

A computer-based minimization algorithm is utilized to obtain the optimum fits of two models to hyperthermic cell killing data. The models chosen are the multitarget, single-hit equation, which is in general use, and the linear-quadratic equation, which has been applied to cell killing by ionizing irradiation but not to heat-induced cell killing. The linear-quadratic equation fits hyperthermic cell killing data as well as the multitarget, single-hit equation. Both parameters of the linear-quadratic equation obey the Arrhenius law, whereas only one of the two parameters of the multitarget, single-hit equation obeys the Arrhenius law. Thus the linear-quadratic function can completely define cell killing as a function of both time and temperature. In addition, the linear-quadratic model will provide a simplified approach to the study of the synergism between heat and X irradiation

Preimplantation Factor (PIF Promotes HLA-G, -E, -F, -C Expression in JEG-3 Choriocarcinoma Cells and Endogenous Progesterone Activity

Directory of Open Access Journals (Sweden)

Miya Soukaina Hakam

2017-10-01

Full Text Available Background/Aims: Pregnancy success requires mandatory maternal tolerance of the semi/ allogeneic embryo involving embryo-derived signals. Expression levels of PreImplantation Factor (PIF, a novel peptide secreted by viable embryos, correlate with embryo development, and its early detection in circulation correlates with a favourable pregnancy outcome. PIF enhances endometrial receptivity to promote embryo implantation. Via the p53 pathway, it increases trophoblast invasion, improving cell survival / immune privilege. PIF also reduces spontaneous and LPS-induced foetal death in immune naïve murine model. We examined PIF effect on gene expression of human leukocyte antigen (HLA-G, -E -F and –C and the influence of PIF on local progesterone activity in JEG-3 choriocarcinoma cells. Methods: PIF and progesterone (P4 effects on JEG-3 cells surface and intracellular HLA molecules was tested using monoclonal antibodies, flow cytometry, and Western blotting. PIF and IL17 effects on P4 and cytokines secretion was determined by ELISA. PIF and P4 effects on JEG-3 cells proteome was examined using 2D gel staining followed by spot analysis, mass spectrometry and bioinformatic analysis. Results: In cytotrophoblastic JEG-3 cells PIF increased intracellular expression of HLA-G, HLA-F, HLA-E and HLA-C and surface expression of HLA-G, HLA-E and HLA-C in dose and time dependent manner. In case of HLA-E, -F results were confirmed also by Western blot. Proteome analysis confirmed an increase in HLA-G, pro-tolerance FOXP3+ regulatory T cells (Tregs, coagulation factors and complement regulator. In contrast, PIF reduced PRDX2 and HSP70s to negate oxidative stress and protein misfolding. PIF enhanced local progesterone activity, increasing steroid secretion and the receptor protein. It also promoted the secretion of the Th1/Th2 cytokines (IL-10, IL-1β, IL-8, GM-CSF and TGF-β1, resulting in improved maternal signalling. Conclusion: PIF can generate a pro

HLA-DR expression and disease activity in ulcerative colitis

DEFF Research Database (Denmark)

Poulsen, L O; Elling, P; Sørensen, Flemming Brandt

1986-01-01

In 12 patients with active ulcerative colitis (UC) the rectal epithelial cells were analyzed for HLA-DR antigens by an immunohistochemical technique. The clinical, rectoscopic, and histologic stages were also determined. The investigations were carried out at the beginning of the study and 2 weeks...... and 3 months later. The rectal epithelial cells were HLA-DR-positive in all patients at the first two examinations. After 3 months five patients had changed to an HLA-DR-negative stage, whereas the other seven patients remained HLA-DR-positive. Closer analyses showed that expression/nonexpression of HLA-DR...... antigens on rectal epithelial cells of patients with UC could not be predicted from the clinical, rectoscopic, or histologic findings. HLA-DR expression is normally restricted to immunocompetent cells. The presence of HLA-DR antigens on epithelial cells may be a consequence of immunological reactions...

Involvement of position-147 for HLA-E expression

International Nuclear Information System (INIS)

Matsunami, Katsuyoshi; Kusama, Tamiko; Okura, Eiji; Shirakura, Ryota; Fukuzawa, Masahiro; Miyagawa, Shuji

2006-01-01

HLA-E functions as an inhibitory signaling molecule of natural killer (NK) cell-mediated cytolysis. However, the cell surface expression of HLA-E molecules is quite restricted because of the limited repertoire of binding peptide sequences, such as signal peptides of other HLA molecules, especially on xenogeneic cells. In this study, we successfully determined that position-147 is an important amino acid position for cell surface expression by producing point substitutions. For further studies concerning transplantation therapy, the point substitution, Ser147Cys, that resulted in a single atom change, oxygen to sulfur, designated as HLA-Ev(147), led to a much higher expression on the human and pig cell surface and a greater inhibitory function against human NK cells than wild type HLA-E in an in vitro model system of pig to human xenotransplantation. Consequently, HLA-Ev(147) might be a promising alternative gene tool for future transplantation therapy such as xenotransplantation

The non-classical antigens of HLA-G and HLA-E as diagnostic and prognostic biomarkers and as therapeutic targets in transplantation and tumors.

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Seliger, Barbara

2013-01-01

The non-classical human leukocyte antigen (HLA) class I antigen HLA-G represents a tolerogenic molecule and is involved in the inhibition of natural killer cell and cytotoxic T lymphocyte-mediated cytotoxicity. Under physiological conditions, HLA-G expression is mainly restricted to immune-privileged tissues, whereas it is overexpressed in tumors and transplants as well as in virus-infected cells. Due to its immunosuppressive features, HLA-G is important for pregnancy or organ transplantation and autoimmune diseases as well as cancer immune escape. This review focusses on the expression, regulation, and function of HLA-G in tumor cells andlor in transplants as well as therapeutic tools for enhancing (transplantation) or avoiding (tumor) tolerance. Thus, HLA-G or HLA-G-derived synthetic molecules might be used as therapeutic agents in combination with immunosuppressive drugs to enhance organ tolerance upon transplantation. In addition, HLA-G neoexpressing tumor cells could be targeted by HLA-G-specific microRNAs in order to enhance tumor immunogenicity.

HLA Class-II Associated HIV Polymorphisms Predict Escape from CD4+ T Cell Responses.

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Nathan Erdmann

2015-08-01

Full Text Available Antiretroviral therapy, antibody and CD8+ T cell-mediated responses targeting human immunodeficiency virus-1 (HIV-1 exert selection pressure on the virus necessitating escape; however, the ability of CD4+ T cells to exert selective pressure remains unclear. Using a computational approach on HIV gag/pol/nef sequences and HLA-II allelic data, we identified 29 HLA-II associated HIV sequence polymorphisms or adaptations (HLA-AP in an African cohort of chronically HIV-infected individuals. Epitopes encompassing the predicted adaptation (AE or its non-adapted (NAE version were evaluated for immunogenicity. Using a CD8-depleted IFN-γ ELISpot assay, we determined that the magnitude of CD4+ T cell responses to the predicted epitopes in controllers was higher compared to non-controllers (p<0.0001. However, regardless of the group, the magnitude of responses to AE was lower as compared to NAE (p<0.0001. CD4+ T cell responses in patients with acute HIV infection (AHI demonstrated poor immunogenicity towards AE as compared to NAE encoded by their transmitted founder virus. Longitudinal data in AHI off antiretroviral therapy demonstrated sequence changes that were biologically confirmed to represent CD4+ escape mutations. These data demonstrate an innovative application of HLA-associated polymorphisms to identify biologically relevant CD4+ epitopes and suggests CD4+ T cells are active participants in driving HIV evolution.

KIR-HLA genotypes in HIV-infected patients lacking immunological recovery despite effective antiretroviral therapy.

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Alessandro Soria

Full Text Available BACKGROUND: In HIV-infected individuals, mechanisms underlying unsatisfactory immune recovery during effective combination antiretroviral therapy (cART have yet to be fully understood. We investigated whether polymorphism of genes encoding immune-regulating molecules, such as killer immunoglobulin-like receptors (KIR and their ligands class I human leukocyte antigen (HLA, could influence immunological response to cART. METHODS: KIR and HLA frequencies were analyzed in 154 HIV-infected and cART-treated patients with undetectable viral load divided into two groups: 'immunological non responders' (INR, N = 50, CD4(+ T-cell count 350/mm(3. Molecular KIR were typed using polymerase chain reaction-based genotyping. Comparisons were adjusted for baseline patient characteristics. RESULTS: The frequency of KIR2DL3 allele was significantly higher in FR than in INR (83.7% vs. 62%, P = 0.005. The functional compound genotype HLA-C1(+/KIR2DL3(+, even at multivariable analysis, when adjusted for nadir CD4(+ T-cell count, was associated with reduced risk of INR status: odds ratio (95% Confidence Intervals 0.34 (0.13-0.88, P = 0.03. CONCLUSIONS: Reduced presence of the inhibitory KIR2DL3 genotype detected in INR might provoke an imbalance in NK function, possibly leading to increased immune activation, impaired killing of latently infected cells, and higher proviral burden. These factors would hinder full immune recovery during therapy.

Strategy for monitoring T cell responses to NY-ESO-1 in patients with any HLA class I allele

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Gnjatic, Sacha; Nagata, Yasuhiro; Jäger, Elke; Stockert, Elisabeth; Shankara, Srinivas; Roberts, Bruce L.; Mazzara, Gail P.; Lee, Sang Yull; Dunbar, P. Rod; Dupont, Bo; Cerundolo, Vincenzo; Ritter, Gerd; Chen, Yao-Tseng; Knuth, Alexander; Old, Lloyd J.

2000-01-01

NY-ESO-1 elicits frequent antibody responses in cancer patients, accompanied by strong CD8+ T cell responses against HLA-A2-restricted epitopes. To broaden the range of cancer patients who can be assessed for immunity to NY-ESO-1, a general method was devised to detect T cell reactivity independent of prior characterization of epitopes. A recombinant adenoviral vector encoding the full cDNA sequence of NY-ESO-1 was used to transduce CD8-depleted peripheral blood lymphocytes as antigen-presenting cells. These modified antigen-presenting cells were then used to restimulate memory effector cells against NY-ESO-1 from the peripheral blood of cancer patients. Specific CD8+ T cells thus sensitized were assayed on autologous B cell targets infected with a recombinant vaccinia virus encoding NY-ESO-1. Strong polyclonal responses were observed against NY-ESO-1 in antibody-positive patients, regardless of their HLA profile. Because the vectors do not cross-react immunologically, only responses to NY-ESO-1 were detected. The approach described here allows monitoring of CD8+ T cell responses to NY-ESO-1 in the context of various HLA alleles and has led to the definition of NY-ESO-1 peptides presented by HLA-Cw3 and HLA-Cw6 molecules. PMID:11005863

Therapeutic preparations of IVIg contain naturally occurring anti-HLA-E antibodies that react with HLA-Ia (HLA-A/-B/-Cw) alleles.

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Ravindranath, Mepur H; Terasaki, Paul I; Pham, Tho; Jucaud, Vadim; Kawakita, Satoru

2013-03-14

The US Food and Drug Administration approved intravenous immunoglobulin (IVIg), extracted from the plasma of thousands of blood donors, for removing HLA antibodies (Abs) in highly sensitized patients awaiting organ transplants. Since the blood of healthy individuals has HLA Abs, we tested different IVIg preparations for reactivity to HLA single antigen Luminex beads. All preparations showed high levels of HLA-Ia and -Ib reactivity. Since normal nonalloimmunized males have natural antibodies to the heavy chains (HCs) of HLA antigens, the preparations were then tested against iBeads coated only with intact HLA antigens. All IVIg preparations varied in level of antibody reactivity to intact HLA antigens. We raised monoclonal Abs against HLA-E that mimicked IVIg's HLA-Ia and HLA-Ib reactivity but reacted only to HLA-I HCs. Inhibition experiments with synthetic peptides showed that HLA-E shares epitopes with HLA-Ia alleles. Importantly, depleting anti-HLA-E Abs from IVIg totally eliminated the HLA-Ia reactivity of IVIg. Since anti-HLA-E mAbs react with HLA-Ia, they might be useful in suppressing HLA antibody production, similar to the way anti-RhD Abs suppress production. At the same time, anti-HLA-E mAb, which reacts only to HLA-I HCs, is unlikely to produce transfusion-related acute lung injury, in contrast to antibodies reacting to intact-HLA.

Distinct mechanisms of loss of IFN-gamma mediated HLA class I inducibility in two melanoma cell lines

International Nuclear Information System (INIS)

Rodríguez, Teresa; Méndez, Rosa; Del Campo, Ana; Jiménez, Pilar; Aptsiauri, Natalia; Garrido, Federico; Ruiz-Cabello, Francisco

2007-01-01

The inability of cancer cells to present antigen on the cell surface via MHC class I molecules is one of the mechanisms by which tumor cells evade anti-tumor immunity. Alterations of Jak-STAT components of interferon (IFN)-mediated signaling can contribute to the mechanism of cell resistance to IFN, leading to lack of MHC class I inducibility. Hence, the identification of IFN-γ-resistant tumors may have prognostic and/or therapeutic relevance. In the present study, we investigated a mechanism of MHC class I inducibility in response to IFN-γ treatment in human melanoma cell lines. Basal and IFN-induced expression of HLA class I antigens was analyzed by means of indirect immunofluorescence flow cytometry, Western Blot, RT-PCR, and quantitative real-time RT-PCR (TaqMan ® Gene Expression Assays). In demethylation studies cells were cultured with 5-aza-2'-deoxycytidine. Electrophoretic Mobility Shift Assay (EMSA) was used to assay whether IRF-1 promoter binding activity is induced in IFN-γ-treated cells. Altered IFN-γ mediated HLA-class I induction was observed in two melanoma cells lines (ESTDAB-004 and ESTDAB-159) out of 57 studied, while treatment of these two cell lines with IFN-α led to normal induction of HLA class I antigen expression. Examination of STAT-1 in ESTDAB-004 after IFN-γ treatment demonstrated that the STAT-1 protein was expressed but not phosphorylated. Interestingly, IFN-α treatment induced normal STAT-1 phosphorylation and HLA class I expression. In contrast, the absence of response to IFN-γ in ESTDAB-159 was found to be associated with alterations in downstream components of the IFN-γ signaling pathway. We observed two distinct mechanisms of loss of IFN-γ inducibility of HLA class I antigens in two melanoma cell lines. Our findings suggest that loss of HLA class I induction in ESTDAB-004 cells results from a defect in the earliest steps of the IFN-γ signaling pathway due to absence of STAT-1 tyrosine-phosphorylation, while absence

NetMHCIIpan-3.0, a common pan-specific MHC class II prediction method including all three human MHC class II isotypes, HLA-DR, HLA-DP and HLA-DQ

DEFF Research Database (Denmark)

Karosiene, Edita; Rasmussen, Michael; Blicher, Thomas

2013-01-01

Major histocompatibility complex class II (MHCII) molecules play an important role in cell-mediated immunity. They present specific peptides derived from endosomal proteins for recognition by T helper cells. The identification of peptides that bind to MHCII molecules is therefore of great importa......MHCIIpan-3.0 method is the first pan-specific predictor covering all HLA class II molecules with known sequences including HLA-DR, HLA-DP, and HLA-DQ. The NetMHCpan-3.0 method is available at http://www.cbs.dtu.dk/services/NetMHCIIpan-3.0....

High risk of graft failure in patients with anti-HLA antibodies undergoing haploidentical stem-cell transplantation.

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Ciurea, Stefan O; de Lima, Marcos; Cano, Pedro; Korbling, Martin; Giralt, Sergio; Shpall, Elizabeth J; Wang, Xuemei; Thall, Peter F; Champlin, Richard E; Fernandez-Vina, Marcelo

2009-10-27

BACKGROUND.: Although donor-specific anti-human leukocyte antigen (HLA) antibodies (DSA) have been implicated in graft rejection in solid organ transplantation, their role in hematopoietic stem-cell transplantation remains unclear. METHODS.: To address the hypothesis that the presence of DSA contributes to the development graft failure, we tested 24 consecutive patients for the presence of anti-HLA antibodies determined by a sensitive and specific solid-phase/single-antigen assay. The study included a total of 28 haploidentical transplants, each with 2 to 5 HLA allele mismatches, at a single institution, from September 2005 to August 2008. RESULTS.: DSA were detected in five patients (21%). Three of four (75%) patients with DSA before the first transplant failed to engraft, compared with 1 of 20 (5%) without DSA (P=0.008). All four patients who experienced primary graft failure had second haploidentical transplants. One patient developed a second graft failure with persistent high DSA levels, whereas three engrafted, two of them in the absence of DSA. No other known factors that could negatively influence engraftment were associated with the development of graft failure in these patients. CONCLUSIONS.: These results suggest that donor-specific anti-HLA antibodies are associated with a high rate of graft rejection in patients undergoing haploidentical stem-cell transplantation. Anti-HLA sensitization should be evaluated routinely in hematopoietic stem-cell transplantation with HLA mismatched donors.

Do protons and X-rays induce cell-killing in human peripheral blood lymphocytes by different mechanisms?

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Miszczyk, J; Rawojć, K; Panek, A; Borkowska, A; Prasanna, P G S; Ahmed, M M; Swakoń, J; Gałaś, A

2018-02-01

Significant progress has been made in the technological and physical aspects of dose delivery and distribution in proton therapy. However, mode of cell killing induced by protons is less understood in comparison with X-rays. The purpose of this study is to see if there is any difference in the mode of cell-killing, induced by protons and X-rays in an ex vivo human peripheral blood lymphocyte (HPBL) model. HPBL were irradiated with 60 MeV proton beam or 250-kVp X-rays in the dose range of 0.3-4.0 Gy. Frequency of apoptotic and necrotic cells was determined by the Fluorescein (FITC)-Annexin V labelling procedure, 1 and 4 h after irradiation. Chip-based DNA Ladder Assay was used to confirm radiation-induced apoptosis and necrosis. Chip-based DNA Ladder Assay was used to confirm radiation-induced apoptosis. Ex vivo irradiation of HPBL with proton beams of 60 MeV or 250 kVp X-rays resulted in apoptotic as well as necrotic modes of cell-killing, which were evident at both 1 and 4 h after irradiation in the whole dose and time range. Generally, our results indicated that protons cause relatively higher yields of cell death that appears to be necrosis compared to X-rays. The analysis also demonstrates that radiation type and dose play a critical role in mode of cell-killing. Obtained results suggest that X-rays and protons induce cell-killing by different modes. Such differences in cell-killing modes may have implications on the potential of a given therapeutic modality to cause immune modulation via programmed cell death (X-rays) or necrotic cell death (proton therapy). These studies point towards exploring for gene expression biomarkers related necrosis or apoptosis to predict immune response after proton therapy.

Modulation of interferon-gamma-induced HLA-DR expression on the human keratinocyte cell line SCC-13 by ultraviolet radiation

International Nuclear Information System (INIS)

Khan, I.U.; Boehm, K.D.; Elmets, C.A.

1993-01-01

Cell surface expression of major histocompatibility determinants on epidermal keratinocytes is a characteristic feature of a number of inflammatory dermatoses and in all likelihood is caused by diffusion of human leukocyte antigen (HLA)-DR-inducing cytokines from cells present in the dermal mononuclear cell infiltrate. Many of these same disorders respond to ultraviolet (UV) radiation phototherapy. Using the human SCC-13 keratinocyte cell line as a model, UV radiation was found to inhibit interferon-gamma-induced HLA-DR expression. Inhibition correlated closely with decreased steady-state levels of HLA-DR mRNA. These findings provide evidence that the therapeutic effect of UV radiation phototherapy may be mediated by its capacity to down-regulate cytokine-induced keratinocyte HLA-DR expression. (Author)

Presentation of an immunodominant immediate-early CD8+ T cell epitope resists human cytomegalovirus immunoevasion.

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Stefanie Ameres

Full Text Available Control of human cytomegalovirus (HCMV depends on CD8+ T cell responses that are shaped by an individual's repertoire of MHC molecules. MHC class I presentation is modulated by a set of HCMV-encoded proteins. Here we show that HCMV immunoevasins differentially impair T cell recognition of epitopes from the same viral antigen, immediate-early 1 (IE-1, that are presented by different MHC class I allotypes. In the presence of immunoevasins, HLA-A- and HLA-B-restricted T cell clones were ineffective, but HLA-C*0702-restricted T cell clones recognized and killed infected cells. Resistance of HLA-C*0702 to viral immunoevasins US2 and US11 was mediated by the alpha3 domain and C-terminal region of the HLA heavy chain. In healthy donors, HLA-C*0702-restricted T cells dominated the T cell response to IE-1. The same HLA-C allotype specifically protected infected cells from attack by NK cells that expressed a corresponding HLA-C-specific KIR. Thus, allotype-specific viral immunoevasion allows HCMV to escape control by NK cells and HLA-A- and HLA-B-restricted T cells, while the virus becomes selectively vulnerable to an immunodominant population of HLA-C-restricted T cells. Our work identifies a T cell population that may be of particular efficiency in HCMV-specific immunotherapy.

Associations of HLA-A, HLA-B and HLA-C Alleles Frequency with Prevalence of Herpes Simplex Virus Infections and Diseases Across Global Populations: Implication for the Development of an Universal CD8+ T-Cell Epitope-Based Vaccine

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Samandary, Sarah; Kridane-Miledi, Hédia; Sandoval, Jacqueline S.; Choudhury, Zareen; Langa-Vives, Francina; Spencer, Doran; Chentoufi, Aziz A.; Lemonnier, François A.; BenMohamed, Lbachir

2014-01-01

A significant portion of the world’s population is infected with herpes simplex virus type 1 and/or type 2 (HSV-1 and/or HSV-2), that cause a wide range of diseases including genital herpes, oro-facial herpes, and the potentially blinding ocular herpes. While the global prevalence and distribution of HSV-1 and HSV-2 infections cannot be exactly established, the general trends indicate that: (i) HSV-1 infections are much more prevalent globally than HSV-2; (ii) Over half billion people worldwide are infected with HSV-2; (iii) the sub-Saharan African populations account for a disproportionate burden of genital herpes infections and diseases; (iv) the dramatic differences in the prevalence of herpes infections between regions of the world appear to be associated with differences in the frequencies of human leukocyte antigen (HLA) alleles. The present report: (i) analyzes the prevalence of HSV-1 and HSV-2 infections across various regions of the world; (ii) analyzes potential associations of common HLA-A, HLA-B and HLA-C alleles with the prevalence of HSV-1 and HSV-2 infections in the Caucasoid, Oriental, Hispanic and Black major populations; and (iii) discusses how our recently developed HLA-A, HLA-B, and HLA-C transgenic/H-2 class I null mice will help validate HLA/herpes prevalence associations. Overall, high prevalence of herpes infection and disease appears to be associated with high frequency of HLA-A*24, HLA-B*27, HLA-B*53 and HLA-B*58 alleles. In contrast, low prevalence of herpes infection and disease appears to be associated with high frequency of HLA-B*44 allele. The finding will aid in developing a T-cell epitope-based universal herpes vaccine and immunotherapy. PMID:24798939

Co-evolution of human leukocyte antigen (HLA class I ligands with killer-cell immunoglobulin-like receptors (KIR in a genetically diverse population of sub-Saharan Africans.

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Paul J Norman

2013-10-01

Full Text Available Interactions between HLA class I molecules and killer-cell immunoglobulin-like receptors (KIR control natural killer cell (NK functions in immunity and reproduction. Encoded by genes on different chromosomes, these polymorphic ligands and receptors correlate highly with disease resistance and susceptibility. Although studied at low-resolution in many populations, high-resolution analysis of combinatorial diversity of HLA class I and KIR is limited to Asian and Amerindian populations with low genetic diversity. At the other end of the spectrum is the West African population investigated here: we studied 235 individuals, including 104 mother-child pairs, from the Ga-Adangbe of Ghana. This population has a rich diversity of 175 KIR variants forming 208 KIR haplotypes, and 81 HLA-A, -B and -C variants forming 190 HLA class I haplotypes. Each individual we studied has a unique compound genotype of HLA class I and KIR, forming 1-14 functional ligand-receptor interactions. Maintaining this exceptionally high polymorphism is balancing selection. The centromeric region of the KIR locus, encoding HLA-C receptors, is highly diverse whereas the telomeric region encoding Bw4-specific KIR3DL1, lacks diversity in Africans. Present in the Ga-Adangbe are high frequencies of Bw4-bearing HLA-B*53:01 and Bw4-lacking HLA-B*35:01, which otherwise are identical. Balancing selection at key residues maintains numerous HLA-B allotypes having and lacking Bw4, and also those of stronger and weaker interaction with LILRB1, a KIR-related receptor. Correspondingly, there is a balance at key residues of KIR3DL1 that modulate its level of cell-surface expression. Thus, capacity to interact with NK cells synergizes with peptide binding diversity to drive HLA-B allele frequency distribution. These features of KIR and HLA are consistent with ongoing co-evolution and selection imposed by a pathogen endemic to West Africa. Because of the prevalence of malaria in the Ga-Adangbe and

Treatment with 5-Aza-2'-Deoxycytidine Induces Expression of NY-ESO-1 and Facilitates Cytotoxic T Lymphocyte-Mediated Tumor Cell Killing.

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Agnes S Klar

Full Text Available NY-ESO-1 belongs to the cancer/testis antigen (CTA family and represents an attractive target for cancer immunotherapy. Its expression is induced in a variety of solid tumors via DNA demethylation of the promoter of CpG islands. However, NY-ESO-1 expression is usually very low or absent in some tumors such as breast cancer or multiple myeloma. Therefore, we established an optimized in vitro treatment protocol for up-regulation of NY-ESO-1 expression by tumor cells using the hypomethylating agent 5-aza-2'-deoxycytidine (DAC.We demonstrated de novo induction of NY-ESO-1 in MCF7 breast cancer cells and significantly increased expression in U266 multiple myeloma cells. This effect was time- and dose-dependent with the highest expression of NY-ESO-1 mRNA achieved by the incubation of 10 μM DAC for 72 hours. NY-ESO-1 activation was also confirmed at the protein level as shown by Western blot, flow cytometry, and immunofluorescence staining. The detection and quantification of single NY-ESO-1 peptides presented at the tumor cell surface in the context of HLA-A*0201 molecules revealed an increase of 100% and 50% for MCF7 and U266 cells, respectively. Moreover, the enhanced expression of NY-ESO-1 derived peptides at the cell surface was accompanied by an increased specific lysis of MCF7 and U266 cells by HLA-A*0201/NY-ESO-1(157-165 peptide specific chimeric antigen receptor (CAR CD8+ T cells. In addition, the killing activity of CAR T cells correlated with the secretion of higher IFN-gamma levels.These results indicate that NY-ESO-1 directed immunotherapy with specific CAR T cells might benefit from concomitant DAC treatment.

HLA-haploidentical transplantation with regulatory and conventional T-cell adoptive immunotherapy prevents acute leukemia relapse.

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Martelli, Massimo F; Di Ianni, Mauro; Ruggeri, Loredana; Falzetti, Franca; Carotti, Alessandra; Terenzi, Adelmo; Pierini, Antonio; Massei, Maria Speranza; Amico, Lucia; Urbani, Elena; Del Papa, Beatrice; Zei, Tiziana; Iacucci Ostini, Roberta; Cecchini, Debora; Tognellini, Rita; Reisner, Yair; Aversa, Franco; Falini, Brunangelo; Velardi, Andrea

2014-07-24

Posttransplant relapse is still the major cause of treatment failure in high-risk acute leukemia. Attempts to manipulate alloreactive T cells to spare normal cells while killing leukemic cells have been unsuccessful. In HLA-haploidentical transplantation, we reported that donor-derived T regulatory cells (Tregs), coinfused with conventional T cells (Tcons), protected recipients against graft-versus-host disease (GVHD). The present phase 2 study investigated whether Treg-Tcon adoptive immunotherapy prevents posttransplant leukemia relapse. Forty-three adults with high-risk acute leukemia (acute myeloid leukemia 33; acute lymphoblastic leukemia 10) were conditioned with a total body irradiation-based regimen. Grafts included CD34(+) cells (mean 9.7 × 10(6)/kg), Tregs (mean 2.5 × 10(6)/kg), and Tcons (mean 1.1 × 10(6)/kg). No posttransplant immunosuppression was given. Ninety-five percent of patients achieved full-donor type engraftment and 15% developed ≥grade 2 acute GVHD. The probability of disease-free survival was 0.56 at a median follow-up of 46 months. The very low cumulative incidence of relapse (0.05) was significantly better than in historical controls. These results demonstrate the immunosuppressive potential of Tregs can be used to suppress GVHD without loss of the benefits of graft-versus-leukemia (GVL) activity. Humanized murine models provided insights into the mechanisms underlying separation of GVL from GVHD, suggesting the GVL effect is due to largely unopposed Tcon alloantigen recognition in bone marrow. © 2014 by The American Society of Hematology.

HLA-A*0201 T-cell epitopes in severe acute respiratory syndrome (SARS) coronavirus nucleocapsid and spike proteins

International Nuclear Information System (INIS)

Tsao, Y.-P.; Lin, J.-Y.; Jan, J.-T.; Leng, C.-H.; Chu, C.-C.; Yang, Y.-C.; Chen, S.-L.

2006-01-01

The immunogenicity of HLA-A*0201-restricted cytotoxic T lymphocyte (CTL) peptide in severe acute respiratory syndrome coronavirus (SARS-CoV) nuclear capsid (N) and spike (S) proteins was determined by testing the proteins' ability to elicit a specific cellular immune response after immunization of HLA-A2.1 transgenic mice and in vitro vaccination of HLA-A2.1 positive human peripheral blood mononuclearcytes (PBMCs). First, we screened SARS N and S amino acid sequences for allele-specific motif matching those in human HLA-A2.1 MHC-I molecules. From HLA peptide binding predictions (http://thr.cit.nih.gov/molbio/hla_bind/), ten each potential N- and S-specific HLA-A2.1-binding peptides were synthesized. The high affinity HLA-A2.1 peptides were validated by T2-cell stabilization assays, with immunogenicity assays revealing peptides N223-231, N227-235, and N317-325 to be First identified HLA-A*0201-restricted CTL epitopes of SARS-CoV N protein. In addition, previous reports identified three HLA-A*0201-restricted CTL epitopes of S protein (S978-986, S1203-1211, and S1167-1175), here we found two novel peptides S787-795 and S1042-1050 as S-specific CTL epitopes. Moreover, our identified N317-325 and S1042-1050 CTL epitopes could induce recall responses when IFN-γ stimulation of blood CD8 + T-cells revealed significant difference between normal healthy donors and SARS-recovered patients after those PBMCs were in vitro vaccinated with their cognate antigen. Our results would provide a new insight into the development of therapeutic vaccine in SARS

Epigenetic priming restores the HLA class-I antigen processing machinery expression in Merkel cell carcinoma

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Ritter, Cathrin; Fan, Kaiji; Paschen, Annette

2017-01-01

Merkel cell carcinoma (MCC) is a rare and aggressive, yet highly immunogenic skin cancer. The latter is due to its viral or UV-associated carcinogenesis. For tumor progression MCC has to escape the host's immuno-surveillance, e.g. by loss of HLA class-I expression. Indeed, a reduced HLA class...

The role of missing killer cell immunoglobulin-like receptor ligands in T cell replete peripheral blood stem cell transplantation from HLA-identical siblings.

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Clausen, Johannes; Kircher, Brigitte; Auberger, Jutta; Schumacher, Petra; Ulmer, Hanno; Hetzenauer, Gabriele; Wolf, Dominik; Gastl, Günther; Nachbaur, David

2010-02-01

The contribution of natural killer (NK) cells to graft-versus-malignancy (GVM) effects following hematopoietic stem cell transplantation (HSCT) remains uncertain, particularly in the HLA-identical setting. A model considering missing HLA ligands to the donor's inhibitory killer cell immunoglobulin-like receptor (KIR), termed the missing KIR ligand model, has been established in T cell depleted bone marrow transplantation (BMT), but lacks validity in other cohorts with different treatment characteristics. We hypothesized that the impact of missing KIR ligands on relapse-free survival (RFS) and overall survival (OS) in T cell replete peripheral blood SCT (PBSCT) differs from that in the T cell depleted BMT setting, and retrospectively evaluated 100 consecutive, HLA-identical sibling transplantations for hematologic malignancies. In addition to KIR ligand status, we considered the donors' activating KIRs and grafted NK, T, and CD34(+) cell doses. Our findings demonstrate noninferiority for OS (P = .005) and RFS (P = .002) for the heterozygous HLA-C group KIR ligand status (C1/2; n = 47) compared with patients missing either C1 or C2 (n = 53). Similarly, OS (P = .031) and RFS (P = .034) of Bw4-positive patients was noninferior to that of patients missing a Bw4 ligand to KIR3DL1. By multivariate analysis, C1/2 heterozygous patients had a favorable risk ratio (RR) for relapse (RR = 0.28; P = .003), RFS (RR = 0.56; P = .046), and acute graft-versus-host disease grade II-IV (RR = 0.36; P = .05). Following reduced-intensity conditioning (RIC), but not standard-intensity conditioning, myeloablative (MA) transplantation, a grafted NK cell dose above the median (3.4 x 10(7)/kg) was associated with a lower risk of relapse (RR = 0.57; P = .003) and improved survival (RR = 0.78; P = .03). Overall, our findings support a role for NK alloreactivity in HLA-identical HSCT, but argue against a favorable impact of missing KIR ligands in the given setting. We conclude that the mechanism

Low immunosuppressive burden after HLA-matched related or unrelated BMT using posttransplantation cyclophosphamide.

Science.gov (United States)

Kanakry, Christopher G; Bolaños-Meade, Javier; Kasamon, Yvette L; Zahurak, Marianna; Durakovic, Nadira; Furlong, Terry; Mielcarek, Marco; Medeot, Marta; Gojo, Ivana; Smith, B Douglas; Kanakry, Jennifer A; Borrello, Ivan M; Brodsky, Robert A; Gladstone, Douglas E; Huff, Carol Ann; Matsui, William H; Swinnen, Lode J; Cooke, Kenneth R; Ambinder, Richard F; Fuchs, Ephraim J; de Lima, Marcos J; Andersson, Borje S; Varadhan, Ravi; O'Donnell, Paul V; Jones, Richard J; Luznik, Leo

2017-03-09

The intensive and prolonged immunosuppressive therapy required to prevent or treat graft-versus-host disease (GVHD) after allogeneic blood or marrow transplantation (alloBMT) puts patients at substantial risk for life-threatening infections, organ toxicity, and disease relapse. Posttransplantation cyclophosphamide (PTCy) can function as single-agent GVHD prophylaxis after myeloablative, HLA-matched related (MRD), or HLA-matched unrelated (MUD) donor T-cell-replete bone marrow allografting, obviating the need for additional prophylactic immunosuppression. However, patients who develop GVHD require supplemental treatment. We assessed the longitudinal requirement for immunosuppressive therapy in 339 patients treated with this transplantation platform: 247 receiving busulfan/cyclophosphamide (BuCy) conditioning (data collected retrospectively) and 92 receiving busulfan/fludarabine (BuFlu) conditioning (data collected prospectively). Approximately 50% of MRD patients and 30% of MUD patients never required immunosuppression beyond PTCy. In patients requiring further immunosuppression, typically only 1 to 2 agents were required, and the median durations of systemic pharmacologic immunosuppression for the BuCy MRD, BuFlu MRD, BuCy MUD, and BuFlu MUD groups all were 4.5 to 5 months. For these 4 groups, 1-year probabilities of being alive and off all systemic immunosuppression were 61%, 53%, 53%, and 51% and 3-year probabilities were 53%, 48%, 49%, and 56%, respectively. These data suggest that PTCy minimizes the global immunosuppressive burden experienced by patients undergoing HLA-matched alloBMT.

Cell killing and mutation induction on Chinese hamster cells by photoradiations

International Nuclear Information System (INIS)

Lam, C.K.C.

1982-11-01

Applying radiation directly on cells, far-uv is more effective than black light, and black light is more effective than white light in inducing proliferative death and in inducing resistance to 6-thioguanine (6-TG), ouabain and diptheria toxin (DT). Gold light has no killing and mutagenic effects on CHO (Chinese hamster ovary) cells. Use of filters showed that a small percentage of shorter wavelengths in the far-uv region is responsible for most of the killing and mutagenic effects in the unfiltered broad spectra of black and white light

Cell killing and mutation induction on Chinese hamster cells by photoradiations

Energy Technology Data Exchange (ETDEWEB)

Lam, C.K.C.

1982-11-01

Applying radiation directly on cells, far-uv is more effective than black light, and black light is more effective than white light in inducing proliferative death and in inducing resistance to 6-thioguanine (6-TG), ouabain and diptheria toxin (DT). Gold light has no killing and mutagenic effects on CHO (Chinese hamster ovary) cells. Use of filters showed that a small percentage of shorter wavelengths in the far-uv region is responsible for most of the killing and mutagenic effects in the unfiltered broad spectra of black and white light.

Differential immunodominance hierarchy of CD8⁺ T-cell responses in HLA-B*27

DEFF Research Database (Denmark)

Adland, Emily; Hill, Matilda; Lavandier, Nora

2018-01-01

The well-characterized association between HLA-B*27:05 and protection against HIV disease progression has been linked to immunodominant HLA-B*27:05- restricted CD8+ T-cell responses toward the conserved Gag KK10 (residues 263 to 272) and polymerase (Pol) KY9 (residues 901 to 909) epitopes. We stu...

Identification of an elaborate NK-specific system regulating HLA-C expression.

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Hongchuan Li

2018-01-01

Full Text Available The HLA-C gene appears to have evolved in higher primates to serve as a dominant source of ligands for the KIR2D family of inhibitory MHC class I receptors. The expression of NK cell-intrinsic MHC class I has been shown to regulate the murine Ly49 family of MHC class I receptors due to the interaction of these receptors with NK cell MHC in cis. However, cis interactions have not been demonstrated for the human KIR and HLA proteins. We report the discovery of an elaborate NK cell-specific system regulating HLA-C expression, indicating an important role for HLA-C in the development and function of NK cells. A large array of alternative transcripts with differences in intron/exon content are generated from an upstream NK-specific HLA-C promoter, and exon content varies between HLA-C alleles due to SNPs in splice donor/acceptor sites. Skipping of the first coding exon of HLA-C generates a subset of untranslatable mRNAs, and the proportion of untranslatable HLA-C mRNA decreases as NK cells mature, correlating with increased protein expression by mature NK cells. Polymorphism in a key Ets-binding site of the NK promoter has generated HLA-C alleles that lack significant promoter activity, resulting in reduced HLA-C expression and increased functional activity. The NK-intrinsic regulation of HLA-C thus represents a novel mechanism controlling the lytic activity of NK cells during development.

ADAM28 localizes to HLA-G+ trophoblasts and promotes column cell outgrowth.

Science.gov (United States)

De Luca, L C; Le, H T; Mara, D L; Beristain, A G

2017-07-01

Trophoblast progenitor cell differentiation towards the extravillous trophoblast (EVT) lineage initiates within proximal regions of anchoring columns of first trimester placental villi. While molecular processes controlling the initial stages of progenitor cell differentiation along the EVT pathway have been described, much remains unknown about factors important in distal column cell differentiation into invasive EVTs. ADAMs are proteases that regulate growth factor signaling, cell-matrix adhesion, and matrix proteolysis, and thus impact many processes relevant in placentation. Global gene expression studies identified the ADAM subtype, ADAM28, to be highly expressed in EVT-like trophoblasts, suggesting that it may play a role in EVT function. This study aims to test the functional importance of ADAM28 in column cell outgrowth and maintenance. ADAM28 mRNA levels and protein localization were determined by qPCR and immunofluorescence microscopy analyses in purified placental villi cell populations and tissues. ADAM28 function in trophoblast column outgrowth was examined using ADAM28-targetting siRNAs in Matrigel-imbedded placental explant cultures. Within placental villi, ADAM28 mRNA levels were highest in HLA-G + column trophoblasts, and consistent with this, ADAM28 was preferentially localized to HLA-G + trophoblasts within distal anchoring columns and decidual tissue. siRNA-directed loss of ADAM28 impaired trophoblast column outgrowth and resulted in increased apoptosis in matrix-invading trophoblasts. Our findings suggest that ADAM28 promotes column outgrowth by providing survival cues within anchoring column cells. This study also provides insight into a possible role for ADAM28 in driving differentiation of column trophoblasts into invasive HLA-G + EVT subsets. Copyright © 2017 Elsevier Ltd. All rights reserved.

Mass spectrometry-based analysis of the HLA-ligandomes of renal cell carcinoma and benign renal tissue

OpenAIRE

Rabsteyn, Armin

2018-01-01

Peptide vaccination is a promising immunotherapeutic approach for the treatment of malignancies. In this project, the unique opportunity to analyze HLA ligandomes of samples from tumor and adjacent benign tissue of renal cell carcinoma (RCC) patients by mass spectrometry was given. This allowed for the establishment of a novel approach of antigen definition by comparative profiling of malignant and benign HLA ligandomes. Analyses were performed for HLA class I and II of tumor and benign tissu...

T-cell memory responses elicited by yellow fever vaccine are targeted to overlapping epitopes containing multiple HLA-I and -II binding motifs.

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Andréa Barbosa de Melo

Full Text Available The yellow fever vaccines (YF-17D-204 and 17DD are considered to be among the safest vaccines and the presence of neutralizing antibodies is correlated with protection, although other immune effector mechanisms are known to be involved. T-cell responses are known to play an important role modulating antibody production and the killing of infected cells. However, little is known about the repertoire of T-cell responses elicited by the YF-17DD vaccine in humans. In this report, a library of 653 partially overlapping 15-mer peptides covering the envelope (Env and nonstructural (NS proteins 1 to 5 of the vaccine was utilized to perform a comprehensive analysis of the virus-specific CD4(+ and CD8(+ T-cell responses. The T-cell responses were screened ex-vivo by IFN-γ ELISPOT assays using blood samples from 220 YF-17DD vaccinees collected two months to four years after immunization. Each peptide was tested in 75 to 208 separate individuals of the cohort. The screening identified sixteen immunodominant antigens that elicited activation of circulating memory T-cells in 10% to 33% of the individuals. Biochemical in-vitro binding assays and immunogenetic and immunogenicity studies indicated that each of the sixteen immunogenic 15-mer peptides contained two or more partially overlapping epitopes that could bind with high affinity to molecules of different HLAs. The prevalence of the immunogenicity of a peptide in the cohort was correlated with the diversity of HLA-II alleles that they could bind. These findings suggest that overlapping of HLA binding motifs within a peptide enhances its T-cell immunogenicity and the prevalence of the response in the population. In summary, the results suggests that in addition to factors of the innate immunity, "promiscuous" T-cell antigens might contribute to the high efficacy of the yellow fever vaccines.

HLA-B7-restricted islet epitopes are differentially recognized in type 1 diabetic children and adults and form weak peptide-HLA complexes

DEFF Research Database (Denmark)

Scotto, Matthieu; Afonso, Georgia; Østerbye, Thomas

2012-01-01

The cartography of β-cell epitopes targeted by CD8(+) T cells in type 1 diabetic (T1D) patients remains largely confined to the common HLA-A2 restriction. We aimed to identify β-cell epitopes restricted by the HLA-B7 (B*07:02) molecule, which is associated with mild T1D protection. Using DNA immu......1D children and adults, and are recognized by IFN-γ(+)TGF-β(+)CD8(+) T cells. These features may explain the T1D-protective effect of HLA-B7. The novel epitopes identified should find valuable applications for immune staging of HLA-B7(+) individuals....

Adoptive immunotherapy using PRAME-specific T cells in medulloblastoma.

Science.gov (United States)

Orlando, Domenico; Miele, Evelina; De Angelis, Biagio; Guercio, Marika; Boffa, Iolanda; Sinibaldi, Matilde; Po, Agnese; Caruana, Ignazio; Abballe, Luana; Carai, Andrea; Caruso, Simona; Camera, Antonio; Moseley, Annemarie; Hagedoorn, Renate S; Heemskerk, Mirjam H M; Giangaspero, Felice; Mastronuzzi, Angela; Ferretti, Elisabetta; Locatelli, Franco; Quintarelli, Concetta

2018-04-03

Medulloblastoma is the most frequent malignant childhood brain tumor with a high morbidity. Identification of new therapeutic targets would be instrumental in improving patient outcomes. We evaluated the expression of the tumor-associated antigen PRAME in biopsies from 60 medulloblastoma patients. PRAME expression was detectable in 82% of tissues independent of molecular and histopathologic subgroups. High PRAME expression also correlated with worse overall survival. We next investigated the relevance of PRAME as a target for immunotherapy. Medulloblastoma cells were targeted using genetically modified T cells with a PRAME-specific TCR (SLL TCR T cells). SLL TCR T cells efficiently killed medulloblastoma HLA-A*02+ DAOY cells as well as primary HLA-A*02+ medulloblastoma cells. Moreover, SLL TCR T cells controlled tumor growth in an orthotopic mouse model of medulloblastoma. To prevent unexpected T cell-related toxicity,an inducible caspase 9 (iC9) gene was introduced in frame with the SLL TCR; this safety switch triggered prompt elimination of genetically-modified T cells. Altogether, these data indicate that T cells genetically modified with a high-affinity, PRAME-specific TCR and iC9 may represent a promising innovative approach for treating HLA-A*02+ medulloblastoma patients. Copyright ©2018, American Association for Cancer Research.

KILLER CELL IMMUNOGLOBULIN-LIKE RECEPTOR GENES AND THEIR HLA-C LIGANDS IN HASHIMOTO THYROIDITIS IN A CHINESE POPULATION.

Science.gov (United States)

Li, Jian-Ting; Guo, Cheng; Li, Ming-Long; Wei, Yong-Qing; Hou, Yan-Feng; Jiao, Yu-Lian; Zhao, Yue-Ran; Sun, Hui; Xu, Jin; Cao, Ming-Feng; Feng, Li; Yu, Gui-Na; Gao, Ling; Liu, Yi-Qing; Zhang, Bing-Chang; Zhao, Jia-Jun; Zhang, Hai-Qing

2016-08-01

Natural killer (NK) cells serve as primary immune surveillance and are partially regulated by combinations of killer immunoglobulin-like receptors (KIR) and their human leukocyte antigen-C (HLA-C) ligands. Alterations in NK cell activity have been associated with Hashimoto thyroiditis (HT). The aim of this study was to determine whether certain KIR/HLA-C genotype combinations play a role in HT pathogenesis. The present study enrolled 107 unrelated HT patients and 108 random healthy individuals in a case-control study. Blood was collected for DNA extraction; typing of KIR genes and HLA-C alleles was performed by polymerase chain reaction with sequence specific primers (PCR-SSP), followed by electrophoresis on agarose gels. Among a panel of KIR2D/HLA-C genotype combinations, the frequency of KIR2DS2/HLA-C1 was significantly increased in HT patients compared to controls (33.64% vs. 12.96%, PHashimoto thyroiditis KIR = killer immunoglobulin-like receptor NK = natural killer PCR = polymerase chain reaction.

76 FR 51374 - Direct Discovery of HLA Associated Influenza Epitopes Isolated From Human Cells for Vaccine and...

Science.gov (United States)

2011-08-18

... direct-discovery technology for use in FDA laboratories. C. Eligibility Information The technology...] Direct Discovery of HLA Associated Influenza Epitopes Isolated From Human Cells for Vaccine and... technology to molecularly characterize peptide epitopes that are processed and presented on soluble HLA...

Conservation and diversity of influenza A H1N1 HLA-restricted T cell epitope candidates for epitope-based vaccines.

Directory of Open Access Journals (Sweden)

Paul Thiamjoo Tan

2010-01-01

Full Text Available The immune-related evolution of influenza viruses is exceedingly complex and current vaccines against influenza must be reformulated for each influenza season because of the high degree of antigenic drift among circulating influenza strains. Delay in vaccine production is a serious problem in responding to a pandemic situation, such as that of the current H1N1 strain. Immune escape is generally attributed to reduced antibody recognition of the viral hemagglutinin and neuraminidase proteins whose rate of mutation is much greater than that of the internal non-structural proteins. As a possible alternative, vaccines directed at T cell epitope domains of internal influenza proteins, that are less susceptible to antigenic variation, have been investigated.HLA transgenic mouse strains expressing HLA class I A*0201, A*2402, and B*0702, and class II DRB1*1501, DRB1*0301 and DRB1*0401 were immunized with 196 influenza H1N1 peptides that contained residues of highly conserved proteome sequences of the human H1N1, H3N2, H1N2, H5N1, and avian influenza A strains. Fifty-four (54 peptides that elicited 63 HLA-restricted peptide-specific T cell epitope responses were identified by IFN-gamma ELISpot assay. The 54 peptides were compared to the 2007-2009 human H1N1 sequences for selection of sequences in the design of a new candidate H1N1 vaccine, specifically targeted to highly-conserved HLA-restricted T cell epitopes.Seventeen (17 T cell epitopes in PB1, PB2, and M1 were selected as vaccine targets based on sequence conservation over the past 30 years, high functional avidity, non-identity to human peptides, clustered localization, and promiscuity to multiple HLA alleles. These candidate vaccine antigen sequences may be applicable to any avian or human influenza A virus.

Expression of the major histocompatibility antigens HLA-A2 and HLA-B7 by DNA-mediated gene transfer

NARCIS (Netherlands)

Bernabeu, C.; Finlay, D.; van de Rijn, M.; Maziarz, R. T.; Biro, P. A.; Spits, H.; de Vries, J.; Terhorst, C. P.

1983-01-01

Genes coding for the heavy chain of the class I antigens HLA-A2 or HLA-B7 of the human major histocompatibility complex have been introduced into mouse LtK- cells by cotransfection with the herpes simplex virus thymidine kinase gene. HAT-resistant colonies were isolated expressing either HLA-A2 or

HLA-DP related suppression of mixed lymphocyte reaction with alloactivated lymphocytes

DEFF Research Database (Denmark)

Ødum, Niels; Hofmann, B; Jakobsen, B K

1986-01-01

We studied the influence of HLA class I and class II antigens on the suppression of the MLR induced by primed lymphocytes (PLs) alloactivated in vitro. The suppression of 14 different PLs of 83 MLRs was analyzed. The PLs were primed against (i) HLA-DP (SB) (ii) HLA-DR/DQ or (iii) both HLA-DP and ...

HLA-DP related suppression of mixed lymphocyte reaction with alloactivated lymphocytes

DEFF Research Database (Denmark)

Ødum, Niels; Hofmann, B; Jakobsen, B K

1986-01-01

We studied the influence of HLA class I and class II antigens on the suppression of the MLR induced by primed lymphocytes (PLs) alloactivated in vitro. The suppression of 14 different PLs of 83 MLRs was analyzed. The PLs were primed against (i) HLA-DP (SB) (ii) HLA-DR/DQ or (iii) both HLA-DP and DR...

IFNA-AS1 regulates CD4+ T cell activation in myasthenia gravis though HLA-DRB1.

Science.gov (United States)

Luo, Mengchuan; Liu, Xiaofang; Meng, Huanyu; Xu, Liqun; Li, Yi; Li, Zhibin; Liu, Chang; Luo, Yue-Bei; Hu, Bo; Xue, Yuanyuan; Liu, Yu; Luo, Zhaohui; Yang, Huan

2017-10-01

Abnormal CD4 + T cell activation is known to play roles in the pathogenesis of myasthenia gravis (MG). However, little is known about the mechanisms underlying the roles of lncRNAs in regulating CD4 + T cell. In this study, we discovered that the lncRNA IFNG-AS1 is abnormally expressed in MG patients associated with quantitative myasthenia gravis (QMG) and the positive anti-AchR Ab levels patients. IFNG-AS1 influenced Th1/Treg cell proliferation and regulated the expression levels of their transcription factors in an experimental autoimmune myasthenia gravis (EAMG)model. IFNG-AS1 could reduce the expression of HLA-DRB and HLA-DOB and they had a negative correlation in MG. Furthermore IFNG-AS1 influenced the expression levels of CD40L and CD4 + T cells activation in MG patient partly depend on effecting the HLA-DRB1 expression. It suggests that IFNG-AS1 may be involved in CD4 + T cell-mediated immune responses in MG. Copyright © 2017 The Authors. Published by Elsevier Inc. All rights reserved.

Influence of HLA class I, HLA class II and KIRs on vertical transmission and chronicity of hepatitis C virus in children.

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A Ruiz-Extremera

Full Text Available There is evidence that maternal viral load of HCV during delivery influences the risk for Mother-to-child transmission (MTCT, but this does not explain all cases. We study the role of the immunogenetic profile (HLA, KIRs and KIR-ligand binding of mothers and children in HCV-MTCT and in chronicity in the children.79 HCV-RNA (+ mothers and their 98 children were included. 24 children were infected, becoming chronic in 8 cases and clearing in 16. HLA-class-I and II and KIRs were determined by Luminex.MTCT study: The presence of HLA-C1-ligand in mothers and/or their children reduces the risk of transmission (mothers: Pc = 0.011, children: P = 0.033, whereas the presence of HLA-C2C2-ligand in mothers increases it (Pc = 0.011. In children KIR2DL3-HLA-C1 is a protector factor (Pc = 0.011. Chronicity in children study: Maternal DQA1*01 allele (Pc = 0.027, KIR2DS1 (Pc = 0.011 or KIR3DS1 (Pc = 0.011 favours chronicity in the child. The presence of the DQB1*03 allele (Pc = 0.027 and KIR2DS3 (P = 0.056 in the child and homozygosity for KIR3DL1/3DL1 (Pc = 0.011 and for the HLA-Bw4/Bw4 ligand (P = 0.027 is associated with viral clearance, whereas the presence of HLA-Bw6 ligand (P = 0.027, the binding of KIR3DS1-HLA-Bw4 (P = 0.037 and heterozygosity for KIR3DL1/3DS1 (Pc = 0.011 favour viral chronicity. Mother/child allele matching: In the joint HLA analysis, matching was greater between mothers and children with chronic infection vs those who had cleared the virus (67%±4.1 vs 57%±1.2, P = 0.003.The HLA-C1 ligand in the mother is related to MTCT, while several genetic factors of the mother or child are involved in the chronification or clearance of infection in the child. Matching allelic data is considered to be an indicator of HCV chronicity in the child and can be used as a potential prognostic test. This implies that NK cells may play a previously undocumented role in protecting against MTCT and that both NK cell immunity and adaptive T-cell responses may

Infection and HLA-G Molecules in Nasal Polyposis

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Roberta Rizzo

2014-01-01

Full Text Available Sinonasal polyposis (SNP is a chronic inflammatory pathology with an unclear aetiopathogenesis. Human papillomavirus (HPV infection is one candidate for the development of SNP for its epithelial cell trophism, hyperproliferative effect, and the induction of immune-modulatory molecules as HLA-G. We enrolled 10 patients with SNP without concomitant allergic diseases (SNP-WoAD, 10 patients with SNP and suffering from allergic diseases (SNP-WAD, and 10 control subjects who underwent rhinoplasty. We analyzed the presence of high- and low-risk HPV DNA and the expression of membrane HLA-G (mHLA-G and IL-10 receptor (IL-10R and of soluble HLA-G (sHLA-G and IL-10 by polyp epithelial cells. The results showed the presence of HPV-11 in 50% of SNP-WoAD patients (OR:5.5, all characterized by a relapsing disease. HPV-11 infection was absent in nonrelapsing SNP-WoAD patients, in SNP-WAD patients and in controls, supporting the hypothesis that HPV-11 increases risk of relapsing disease. HPV-11 positive SNP-WoAD patients presented with mHLA-G and IL-10R on epithelial cells from nasal polyps and showed secretion of sHLA-G and IL-10 in culture supernatants. No HLA-G expression was observed in HPV negative polyps. These data highlight new aspects of polyposis aetiopathogenesis and suggest HPV-11 and HLA-G/IL-10 presence as prognostic markers in the follow-up of SNP-WoAD.

Defective HLA class I antigen processing machinery in cancer.

Science.gov (United States)

Cai, Lei; Michelakos, Theodoros; Yamada, Teppei; Fan, Song; Wang, Xinhui; Schwab, Joseph H; Ferrone, Cristina R; Ferrone, Soldano

2018-02-27

Malignant transformation of cells is frequently associated with defective HLA class I antigen processing machinery (APM) component expression. This abnormality may have functional relevance, since it may have a negative impact on tumor cell recognition by cognate T cells. Furthermore, HLA class I APM abnormalities appear to have clinical significance, since they are associated with poor prognosis in several malignant diseases and may play a role in the resistance to immune checkpoint inhibitor-based immunotherapy. In this paper, we have reviewed the literature describing abnormalities in HLA class I APM component expression in many types of cancer. These abnormalities have been reported in all types of cancer analyzed with a frequency ranging between a minimum of 35.8% in renal cancer and a maximum of 87.9% in thyroid cancer for HLA class I heavy chains. In addition, we have described the molecular mechanisms underlying defects in HLA class I APM component expression and function by malignant cells. Lastly, we have discussed the clinical significance of HLA class I APM component abnormalities in malignant tumors.

Cell surface expression level variation between two common Human Leukocyte Antigen alleles, HLA-A2 and HLA-B8, is dependent on the structure of the C terminal part of the alpha 2 and the alpha 3 domains

DEFF Research Database (Denmark)

Dellgren, Christoffer; Nehlin, Jan O; Barington, Torben

2015-01-01

Constitutive cell surface expression of Human Leukocyte Antigen (HLA) class I antigens vary extremely from tissue to tissue and individual antigens may differ widely in expression levels. Down-regulation of class I expression is a known immune evasive mechanism used by cancer cells and viruses....... Moreover, recent observations suggest that even minor differences in expression levels may influence the course of viral infections and the frequency of complications to stem cell transplantation. We have shown that some human multipotent stem cells have high expression of HLA-A while HLA-B is only weakly...... expressed, and demonstrate here that this is also the case for the human embryonic kidney cell line HEK293T. Using quantitative flow cytometry and quantitative polymerase chain reaction we found expression levels of endogenous HLA-A3 (median 71,204 molecules per cell) 9.2-fold higher than the expression of...

Effect of cell density and HLA-DR incompatibility on T-cell proliferation and forkhead box P3 expression in human mixed lymphocyte reaction.

Science.gov (United States)

Song, E Y; Han, S; Yang, B; Morris, G P; Bui, J D

2015-04-01

The proliferation rates of human T cells in vitro are affected by some factors such as initial T-cell number, dose of stimulating cells, and duration of culture. The transcription factor forkhead box P3 (FoxP3) has been used to identify regulatory T cells in humans and is thought to correlate with tolerance to allogeneic organ transplant. Thus, it is important to optimize conditions to expand FoxP3 cell proliferation to improve engraftment of allogeneic organ transplants. We studied proliferative responses and FoxP3 expression in divided T cells with the use of flow cytometric analysis of Ki-67 in culture of different concentrations of responding cells (6 × 10(6), 4 × 10(6), 2 × 10(6), 1 × 10(6), and 0.5 × 10(6)cells/mL), different types of stimulating cells (lymphocytes and low density cells), and different numbers of HLA mismatches. The proportion of CD3(+) cells, CD4(+)CD25(+) cells, and CD4(+)CD25(+)FoxP3(+) cells among mononuclear cells were highest at initial cell concentration of 2 × 10(6) responder cells/mL with lymphocytes as stimulators at day-5 mixed lymphocyte reaction (MLR). They were highest at a concentration of 4 × 10(6) responder cells/mL with low density cells as stimulators. The recovery (%), proportion of CD3(+) cells, CD4(+)CD25(+) cells, and CD4(+)CD25(+)FoxP3(+) cells with 2 HLA-DR incompatibility were significantly higher than those of 1 HLA-DR incompatibility at day-5 MLR. Initial cell concentration and HLA-DR incompatibility can affect the generation of FoxP3+ T cells in human MLR. These factors could be considered for efficient generation of Tregs for clinical trials in the future. Copyright © 2015 Elsevier Inc. All rights reserved.

The immunodominant influenza matrix t cell epitope recognized in human induces influenza protection in HLA-A2/Kb transgenic mice

International Nuclear Information System (INIS)

Plotnicky, H.; Cyblat-Chanal, D.; Aubry, J.-P.; Derouet, F.; Klinguer-Hamour, C.; Beck, A.; Bonnefoy, J.-Y.; Corvaiea, N.

2003-01-01

The protective efficacy of the influenza matrix protein epitope 58-66 (called M1), recognized in the context of human HLA-A2 molecules, was evaluated in a HLA-A2/K b transgenic mouse model of lethal influenza infection. Repeated subcutaneous immunizations with M1 increased the percentage of survival. This effect was mediated by T cells since protection was abolished following in vivo depletion of all T lymphocytes, CD8 + , or CD4 + T cells. The survival correlated with the detection of memory CD8 + splenocytes able to proliferate in vitro upon stimulation with M1 and to bind M1-loaded HLA-A2 dimers, as well as with M1-specific T cells in the lungs, which were directly cytotoxic to influenza-infected cells following influenza challenge. These results demonstrated for the first time that HLA-A2-restricted cytotoxic T cells specific for the major immunodominant influenza matrix epitope are protective against the infection. They encourage further in vivo evaluation of T cell epitopes recognized in the context of human MHC molecules

Relevance of MICA and other non-HLA antibodies in clinical transplantation.

Science.gov (United States)

Sumitran-Holgersson, Suchitra

2008-10-01

The clinical importance of HLA-specific antibodies for organ allograft outcome is well established. In the past few years, there has been an increasing interest in non-HLA antigens as targets of injury in organ transplant recipients. This increased interest has been spurred by the fact that HLA-identical kidney transplants also undergo immunological rejections. Polymorphisms within non-HLA genes associated with evoking an immune response to alloantigens are currently being studied for their association with transplant outcome. Non-HLA antigens, such as the polymorphic MHC class I-related chain A (MICA), expressed on endothelial cells have been implicated in the pathogenesis of hyperacute, acute and chronic organ allograft rejections. Use of endothelial cells as targets may clarify the specificities of other clinically relevant non-HLA antibodies in graft rejections. This review summarizes past and current knowledge of the clinical importance and specificities of non-HLA antibodies, and mechanisms by which these antibodies may contribute to graft destruction in clinical transplantation. The aims of current research into the role of non-HLA antigens and their genetics in predicting outcome are to develop an improved insight into the basic science of transplantation and to develop a risk or prognostic index for use in the clinical setting. Non-HLA antibody responses are receiving increasing interest in acute and chronic rejection and specificity, affinity, and pathogenicity need to be investigated to estimate their contribution. Undoubtedly, this will continue to be an area of interest in terms of fully understanding the role of non-HLA antigens as targets of immune-mediated injury and the potential for clinical intervention.

Individual motile CD4+ T cells can participate in efficient multi-killing through conjugation to multiple tumor cells

Science.gov (United States)

Liadi, Ivan; Singh, Harjeet; Romain, Gabrielle; Rey-Villamizar, Nicolas; Merouane, Amine; Adolacion, Jay R T.; Kebriaei, Partow; Huls, Helen; Qiu, Peng; Roysam, Badrinath; Cooper, Laurence J.N.; Varadarajan, Navin

2015-01-01

T cells genetically modified to express a CD19-specific chimeric antigen receptor (CAR) for the investigational treatment of B-cell malignancies comprise a heterogeneous population, and their ability to persist and participate in serial killing of tumor cells is a predictor of therapeutic success. We implemented Timelapse Imaging Microscopy In Nanowell Grids (TIMING) to provide direct evidence that CD4+CAR+ T cells (CAR4 cells) can engage in multi-killing via simultaneous conjugation to multiple tumor cells. Comparisons of the CAR4 cells and CD8+CAR+ T cells (CAR8 cells) demonstrate that while CAR4 cells can participate in killing and multi-killing, they do so at slower rates, likely due to the lower Granzyme B content. Significantly, in both sets of T cells, a minor sub-population of individual T cells identified by their high motility, demonstrated efficient killing of single tumor cells. By comparing both the multi-killer and single killer CAR+ T cells it appears that the propensity and kinetics of T-cell apoptosis was modulated by the number of functional conjugations. T cells underwent rapid apoptosis, and at higher frequencies, when conjugated to single tumor cells in isolation and this effect was more pronounced on CAR8 cells. Our results suggest that the ability of CAR+ T cells to participate in multi-killing should be evaluated in the context of their ability to resist activation induced cell death (AICD). We anticipate that TIMING may be utilized to rapidly determine the potency of T-cell populations and may facilitate the design and manufacture of next-generation CAR+ T cells with improved efficacy. PMID:25711538

Heat-killed Lactobacillus spp. cells enhance survivals of Caenorhabditis elegans against Salmonella and Yersinia infections.

Science.gov (United States)

Lee, J; Choe, J; Kim, J; Oh, S; Park, S; Kim, S; Kim, Y

2015-12-01

This study examined the effect of feeding heat-killed Lactobacillus cells on the survival of Caenorhabditis elegans nematodes after Salmonella Typhimurium and Yersinia enterocolitica infection. The feeding of heat-killed Lactobacillus plantarum 133 (LP133) and Lactobacillus fermentum 21 (LP21) cells to nematodes was shown to significantly increase the survival rate as well as stimulate the expression of pmk-1 gene that key factor for C. elegans immunity upon infection compared with control nematodes that were only fed Escherichia coli OP50 (OP50) cells. These results suggest that heat-killed LP133 and LF21 cells exert preventive or protective effects against the Gram-negative bacteria Salm. Typhimurium and Y. enterocolitica. To better understand the mechanisms underlying the LF21-mediated and LP133-mediated protection against bacterial infection in nematodes, transcriptional profiling was performed for each experimental group. These experiments showed that genes related to energy generation and ageing, regulators of insulin/IGF-1-like signalling, DAF genes, oxidation and reduction processes, the defence response and/or the innate immune response, and neurological processes were upregulated in nematodes that had been fed heat-killed Lactobacillus cells compared with nematodes that had been fed E. coli cells. In this study, the feeding of heat-killed Lactobacillus bacteria to Caenorhabditis elegans nematodes was shown to decrease infection by Gram-negative bacteria and increase the host lifespan. C. elegans has a small, well-organized genome and is an excellent in vivo model organism; thus, these results will potentially shed light on important Lactobacillus-host interactions. © 2015 The Society for Applied Microbiology.

HLA-A AND HLA-B ALLELES ASSOCIATED IN PSORIASIS PATIENTS FROM MUMBAI, WESTERN INDIA

Science.gov (United States)

Umapathy, Shankarkumar; Pawar, Aruna; Mitra, R; Khuperkar, D; Devaraj, J P; Ghosh, K; Khopkar, U

2011-01-01

Background: Psoriasis, a common autoimmune disorder characterized by T cell-mediated keratinocyte hyperproliferation, is known to be associated with the presence of certain specific Human Leukocyte Antigen (HLA) alleles. Aim: To evaluate distribution of HLA-A and HLA-B alleles and hence identify the susceptible allele of psoriasis from patients in Western India. Materials and Methods: The study design included 84 psoriasis patients and 291 normal individuals as controls from same geographical region. HLA-A and HLA-B typing was done using Serology typing. Standard statistical analysis was followed to identify the odds ratio (OR), allele frequencies, and significant P value using Graphpad software. Results: The study revealed significant increase in frequencies of HLA-A2 (OR-3.976, P<0.0001), B8 (OR-5.647, P<0.0001), B17 (OR-5.452, P<0.0001), and B44 (OR-50.460, P<0.0001), when compared with controls. Furthermore, the frequencies of HLA-A28 (OR-0.074, P=0.0024), B5 (OR-0.059, P<0.0001), B12 (OR-0.051, P=0.0002), and B15 (OR-0.237, P=0.0230) were significantly decreased in psoriasis patients. Conclusion: This study shows the strong association of HLA-A2, B8, and B17 antigens with psoriasis conferring susceptibility to psoriasis patients from Western India, while the antigens HLA-A28, B5, and B12 show strong negative association with the disease. PMID:22121262

Assessment of Impact of HLA Type on Outcomes of Allogeneic Hematopoietic Stem Cell Transplantation for Chronic Lymphocytic Leukemia.

Science.gov (United States)

Hill, Brian T; Ahn, Kwang Woo; Hu, Zhen-Huan; Aljurf, Mahmoud; Beitinjaneh, Amer; Cahn, Jean-Yves; Cerny, Jan; Kharfan-Dabaja, Mohamed A; Ganguly, Siddhartha; Ghosh, Nilanjan; Grunwald, Michael R; Inamoto, Yoshihiro; Kindwall-Keller, Tamila; Nishihori, Taiga; Olsson, Richard F; Saad, Ayman; Seftel, Matthew; Seo, Sachiko; Szer, Jeffrey; Tallman, Martin; Ustun, Celalettin; Wiernik, Peter H; Maziarz, Richard T; Kalaycio, Matt; Alyea, Edwin; Popat, Uday; Sobecks, Ronald; Saber, Wael

2018-03-01

Chronic lymphocytic leukemia (CLL) is a common hematologic malignancy with many highly effective therapies. Chemorefractory disease, often characterized by deletion of chromosome 17p, has historically been associated with very poor outcomes, leading to the application of allogeneic hematopoietic stem cell transplantation (allo-HCT) for medically fit patients. Although the use of allo-HCT has declined since the introduction of novel targeted therapy for the treatment of CLL, there remains significant interest in understanding factors that may influence the efficacy of allo-HCT, the only known curative treatment for CLL. The potential benefit of transplantation is most likely due to the presence of alloreactive donor T cells that mediate the graft-versus-leukemia (GVL) effect. The recognition of potentially tumor-specific antigens in the context of class I and II major histocompatibility complex on malignant B lymphocytes by donor T cells may be influenced by subtle differences in the highly polymorphic HLA locus. Given previous reports of specific HLA alleles impacting the incidence of CLL and the clinical outcomes of allo-HCT for CLL, we sought to study the overall survival and progression-free survival of a large cohort of patients with CLL who underwent allo-HCT from fully HLA-matched related and unrelated donors at Center for International Blood and Marrow Transplant Research transplantation centers. We found no statistically significant association of allo-HCT outcomes in CLL based on previously reported HLA combinations. Additional study is needed to further define the immunologic features that portend a more favorable GVL effect after allo-HCT for CLL. Copyright © 2017 The American Society for Blood and Marrow Transplantation. Published by Elsevier Inc. All rights reserved.

HLA-DR expression and disease activity in ulcerative colitis

DEFF Research Database (Denmark)

Poulsen, L O; Elling, P; Sørensen, Flemming Brandt

1986-01-01

and 3 months later. The rectal epithelial cells were HLA-DR-positive in all patients at the first two examinations. After 3 months five patients had changed to an HLA-DR-negative stage, whereas the other seven patients remained HLA-DR-positive. Closer analyses showed that expression/nonexpression of HLA...

Different binding motifs of the celiac disease-associated HLA molecules DQ2.5, DQ2.2, and DQ7.5 revealed by relative quantitative proteomics of endogenous peptide repertoires

DEFF Research Database (Denmark)

Bergseng, Elin; Dørum, Siri; Arntzen, Magnus Ø.

2014-01-01

Celiac disease is caused by intolerance to cereal gluten proteins, and HLA-DQ molecules are involved in the disease pathogenesis by presentation of gluten peptides to CD4+ T cells. The α- or β-chain sharing HLA molecules DQ2.5, DQ2.2, and DQ7.5 display different risks for the disease...... established binding motifs. The binding motif of DQ2.2 was strikingly different from that of DQ2.5 with position P3 being a major anchor having a preference for threonine and serine. This is notable as three recently identified epitopes of gluten recognized by T cells of DQ2.2 celiac patients harbor serine...... at position P3. This study demonstrates that relative quantitative comparison of endogenous peptides sampled from our protein metabolism by HLA molecules provides clues to understand HLA association with disease....

Rate-limiting events in hyperthermic cell killing

International Nuclear Information System (INIS)

Landry, J.; Marceau, N.

1978-01-01

The inactivation rate of HeLa cells for temperatures ranging from 41 to 55 0 C and treatment durations varying from 2 to 300 min was analyzed in thermodynamic terms by considering the dependence of cell free energy (ΔG + ) on temperature. Within this temperature range the loss of proliferative capacity exhibits a complex temperature dependence which is characterized by entropy and enthalpy values that gradually decrease as temperature increases. This complex process of heat-induced cell killing was postulated to be the result of a series of reactions, each of them being alternatively rate limiting within a certain temperature range. From this kinetic scheme a mathematical model was derived and, in the case of HeLa cells, the use of a least-squares search parameter procedure (as applied to the derived survival regression function) demonstrated that three such sequential reactions were sufficient to explain all experimental data points obtained within the 41 to 55 0 C range. The proposed model was also shown to be adequate for explaining survival data of HeLa cells exposed to nanosecond heat pulses of infrared laser energy. Considerations of thermodynamic properties of known biochemical reactions suggest plausible rate-limiting events in hyperthermic cell killing

Selective Killing of Prostate Tumor Cells by Cytocidal Viruses

National Research Council Canada - National Science Library

Lyles, Douglas

2003-01-01

.... The novelty in our approach is our ability to enhance the selectivity of killing of tumor cells versus normal cells by manipulating the viral genes that control the antiviral interferon response...

Selective Killing of Prostate Tumor Cells by Cytocidal Viruses

National Research Council Canada - National Science Library

Lyles, Douglas

2004-01-01

.... The novelty in our approach is our ability to enhance the selectivity of killing of tumor cells versus normal cells by manipulating the viral genes that control the antiviral interferon response...

The kinematics of cytotoxic lymphocytes influence their ability to kill target cells.

Directory of Open Access Journals (Sweden)

Purnima Bhat

Full Text Available Cytotoxic lymphocytes (CTL have been reported to show a range of motility patterns from rapid long-range tracking to complete arrest, but how and whether these kinematics affect their ability to kill target cells is not known. Many in vitro killing assays utilize cell lines and tumour-derived cells as targets, which may be of limited relevance to the kinetics of CTL-mediated killing of somatic cells. Here, live-cell microscopy is used to examine the interactions of CTL and primary murine skin cells presenting antigens. We developed a qualitative and quantitative killing assay using extended-duration fluorescence time-lapse microscopy coupled with large-volume objective software-based data analysis to obtain population data of cell-to-cell interactions, motility and apoptosis. In vivo and ex vivo activated antigen-specific cytotoxic lymphocytes were added to primary keratinocyte targets in culture with fluorometric detection of caspase-3 activation in targets as an objective determinant of apoptosis. We found that activated CTL achieved contact-dependent apoptosis of non-tumour targets after a period of prolonged attachment - on average 21 hours - which was determined by target cell type, amount of antigen, and activation status of CTL. Activation of CTL even without engagement of the T cell receptor was sufficient to mobilise cells significantly above baseline, while the addition of cognate antigen further enhanced their motility. Highly activated CTL showed markedly increased vector displacement, and velocity, and lead to increased antigen-specific target cell death. These data show that the inherent kinematics of CTL correlate directly with their ability to kill non-tumour cells presenting cognate antigen.

Diversity of natural self-derived ligands presented by different HLA class I molecules in transporter antigen processing-deficient cells.

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Elena Lorente

Full Text Available The transporter associated with antigen processing (TAP translocates the cytosol-derived proteolytic peptides to the endoplasmic reticulum lumen where they complex with nascent human leukocyte antigen (HLA class I molecules. Non-functional TAP complexes and viral or tumoral blocking of these transporters leads to reduced HLA class I surface expression and a drastic change in the available peptide repertoire. Using mass spectrometry to analyze complex human leukocyte antigen HLA-bound peptide pools isolated from large numbers of TAP-deficient cells, we identified 334 TAP-independent ligands naturally presented by four different HLA-A, -B, and -C class I molecules with very different TAP dependency from the same cell line. The repertoire of TAP-independent peptides examined favored increased peptide lengths and a lack of strict binding motifs for all four HLA class I molecules studied. The TAP-independent peptidome arose from 182 parental proteins, the majority of which yielded one HLA ligand. In contrast, TAP-independent antigen processing of very few cellular proteins generated multiple HLA ligands. Comparison between TAP-independent peptidome and proteome of several subcellular locations suggests that the secretory vesicle-like organelles could be a relevant source of parental proteins for TAP-independent HLA ligands. Finally, a predominant endoproteolytic peptidase specificity for Arg/Lys or Leu/Phe residues in the P(1 position of the scissile bond was found for the TAP-independent ligands. These data draw a new and intricate picture of TAP-independent pathways.

Generation of B-cell chronic lymphocytic leukemia (B-CLL)-reactive T-cell lines and clones from HLA class I-matched donors using modified B-CLL cells as stimulators: implications for adoptive immunotherapy.

Science.gov (United States)

Hoogendoorn, M; Wolbers, J Olde; Smit, W M; Schaafsma, M R; Barge, R M Y; Willemze, R; Falkenburg, J H F

2004-07-01

Allogeneic stem cell transplantation following reduced-intensity conditioning is being evaluated in patients with advanced B-cell chronic lymphocytic leukemia (B-CLL). The curative potential of this procedure is mediated by donor-derived alloreactive T cells, resulting in a graft-versus-leukemia effect. However, B-CLL may escape T-cell-mediated immune reactivity since these cells lack expression of costimulatory molecules. We examined the most optimal method to transform B-CLL cells into efficient antigen-presenting cells (APC) using activating cytokines, by triggering toll-like receptors (TLRs) using microbial pathogens and by CD40 stimulation with CD40L-transfected fibroblasts. CD40 activation in the presence of IL-4 induced strongest upregulation of costimulatory and adhesion molecules on B-CLL cells and induced the production of high amounts of IL-12 by the leukemic cells. In contrast to primary B-CLL cells as stimulator cells, these malignant APCs were capable of inducing the generation of B-CLL-reactive CD8(+) CTL lines and clones from HLA class I-matched donors. These CTL lines and clones recognized and killed primary B-CLL as well as patient-derived lymphoblasts, but not donor cells. These results show the feasibility of ex vivo generation of B-CLL-reactive CD8(+) CTLs. This opens new perspectives for adoptive immunotherapy, following allogeneic stem cell transplantation in patients with advanced B-CLL.

Melanoma cells present high levels of HLA-A2-tyrosinase in association with instability and aberrant intracellular processing of tyrosinase.

Science.gov (United States)

Michaeli, Yael; Sinik, Keren; Haus-Cohen, Maya; Reiter, Yoram

2012-04-01

Short-lived protein translation products are proposed to be a major source of substrates for major histocompatibility complex (MHC) class I antigen processing and presentation; however, a direct link between protein stability and the presentation level of MHC class I-peptide complexes has not been made. We have recently discovered that the peptide Tyr((369-377)) , derived from the tyrosinase protein is highly presented by HLA-A2 on the surface of melanoma cells. To examine the molecular mechanisms responsible for this presentation, we compared characteristics of tyrosinase in melanoma cells lines that present high or low levels of HLA-A2-Tyr((369-377)) complexes. We found no correlation between mRNA levels and the levels of HLA-A2-Tyr((369-377)) presentation. Co-localization experiments revealed that, in cell lines presenting low levels of HLA-A2-Tyr((369-377)) complexes, tyrosinase co-localizes with LAMP-1, a melanosome marker, whereas in cell lines presenting high HLA-A2-Tyr((369-377)) levels, tyrosinase localizes to the endoplasmic reticulum. We also observed differences in tyrosinase molecular weight and glycosylation composition as well as major differences in protein stability (t(1/2) ). By stabilizing the tyrosinase protein, we observed a dramatic decrease in HLA-A2-tyrosinase presentation. Our findings suggest that aberrant processing and instability of tyrosinase are responsible for the high presentation of HLA-A2-Tyr((369-377)) complexes and thus shed new light on the relationship between intracellular processing, stability of proteins, and MHC-restricted peptide presentation. © 2012 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

Glucocorticoids and Polyamine Inhibitors Synergize to Kill Human Leukemic CEM Cells

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Aaron L. Miller

2002-01-01

Full Text Available Glucocorticoids are well-known apoptotic agents in certain classes of lymphoid cell malignancies. Reduction of intracellular polyamine levels by use of inhibitors that block polyamine synthesis slows or inhibits growth of many cells in vitro. Several such inhibitors have shown efficacy in clinical trials, though the toxicity of some compounds has limited their usefulness. We have tested the effects of combinations of the glucocorticoid dexamethasone. (20Dex and two polyamine inhibitors, difluoromethylornithine. (20DFMO and methyl glyoxal bis guanylhydrazone. (20MGBG, on the clonal line of human acute lymphoblastic leukemia cells, CEM-C7-14. Dex alone kills these cells, though only after a delay of at least 24 hours. We also evaluated a partially glucocorticoid-resistant c-Myc-expressing CEM-C7-14 clone. We show that Dex downregulates ornithine decarboxylase. (20ODC, the rate-limiting enzyme in polyamine synthesis. Pretreatment with the ODC inhibitor DFMO, followed by addition of Dex, enhances steroid-evoked kill slightly. The combination of pretreatment with sublethal concentrations of both DFMO and the inhibitor of S-adenosylmethionine decarboxylase, MGBG, followed by addition of Dex, results in strong synergistic cell kill. Both the rapidity and extent of cell kill are enhanced compared to the effects of Dex alone. These results suggest that use of such combinations in vivo may result in apoptosis of malignant cells with lower overall toxicity.

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

DEFF Research Database (Denmark)

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

2005-01-01

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

Functional and Structural Characterization of a Novel HLA-DRB1*04:01-Restricted α-Enolase T Cell Epitope in Rheumatoid Arthritis

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Christina Gerstner

2016-11-01

Full Text Available Antibodies to citrullinated proteins, common in rheumatoid arthritis (RA patients, are strongly associated to a specific set of HLA-DR alleles including HLA-DRB1*04:01, *04:04, and *01:01. Here, we first demonstrate that autoantibody levels toward the dominant citrullinated B cell epitope from α-enolase are significantly elevated in HLA-DRB1*04:01-positive RA patients. Furthermore, we identified α-enolase-derived T cell epitopes and demonstrated that native and citrullinated versions of several peptides bind with different affinities to HLA-DRB1*04:01, *04:04, and *01:01. The citrulline residues in the eight identified peptides are distributed throughout the entire length of the presented epitopes and more specifically, localized at peptide positions p-2, p2, p4, p6, p7, p10, and p11. Importantly, in contrast to its native version peptide 26 (TSKGLFRAAVPSGAS, the HLA-DRB1*04:01-restricted citrullinated peptide Cit26 (TSKGLFCitAAVPSGAS elicited significant functional T cell responses in primary cells from RA patients. Comparative analysis of the crystal structures of HLA-DRB1*04:01 in complex with peptide 26 or Cit26 demonstrated that the posttranslational modification did not alter the conformation of the peptide. And since citrullination is the only structural difference between the two complexes, this indicates that the neo-antigen Cit26 is recognized by T cells with high specificity to the citrulline residue.

Selective Killing of Prostate Tumor Cells by Cytocidal Viruses

National Research Council Canada - National Science Library

Lyles, Douglas S

2005-01-01

...). The novelty in our approach is our ability to enhance the selectivity of VSV-induced killing of tumor cells versus normal cells by manipulating the viral genes that control the antiviral interferon response...

HLA-G Expression Pattern: Reliable Assessment for Pregnancy Outcome Prediction

Science.gov (United States)

Mosaferi, Elnaz; Majidi, Jafar; Mohammadian, Mojdeh; Babaloo, Zohreh; Monfaredan, Amir; Baradaran, Behzad

2013-01-01

Because mothers and fathers are more or less dissimilar at multiple HLA loci, mother considers her fetus as a semi-allograft. Mother's immune system may recognize paternal HLA as foreign antigen and may develop anti-paternal HLA antibodies and cytotoxic T lymphocyte. There are some mechanisms that modulate maternal immune responses during pregnancy, in order to make uterus an immune privileged site. This immunosuppression is believed to be mediated, at least partly, by HLA-G, non-classical class I human leukocyte antigen (HLA) molecule that is strongly expressed in cytotrophoblast and placenta. The major HLA-G function is its ability to inhibit T and B lymphocytes, NK cells and antigen-presenting cells (APC).Since HLA-G is expressed strongly at the maternofetal interface and has an essential role in immunosuppression, HLA-G polymorphism and altered expression of HLA-G seems to be associated with some complications of pregnancy, such as pre-eclampsia, recurrent misscariage and failure in IVF.This perspective discusses recent findings about HLA-G genetics, function, expression and polymorphism; and focus on HLA-G role in the etiology of recurrent miscarriage. PMID:24312875

HLA-G Expression Pattern: Reliable Assessment for Pregnancy Outcome Prediction

Directory of Open Access Journals (Sweden)

Elnaz Mosaferi

2013-08-01

Full Text Available Because mothers and fathers are more or less dissimilar at multiple HLA loci, mother considers her fetus as a semi-allograft. Mother's immune system may recognize paternal HLA as foreign antigen and may develop anti-paternal HLA antibodies and cytotoxic T lymphocyte. There are some mechanisms that modulate maternal immune responses during pregnancy, in order to make uterus an immune privileged site. This immunosuppression is believed to be mediated, at least partly, by HLA-G, non-classical class I human leukocyte antigen (HLA molecule that is strongly expressed in cytotrophoblast and placenta. The major HLA-G function is its ability to inhibit T and B lymphocytes, NK cells and antigen-presenting cells (APC.Since HLA-G is expressed strongly at the maternofetal interface and has an essential role in immunosuppression, HLA-G polymorphism and altered expression of HLA-G seems to be associated with some complications of pregnancy, such as pre-eclampsia, recurrent misscariage and failure in IVF.This perspective discusses recent findings about HLA-G genetics, function, expression and polymorphism; and focus on HLA-G role in the etiology of recurrent miscarriage.

Asymptomatic HLA-A*02:01–Restricted Epitopes from Herpes Simplex Virus Glycoprotein B Preferentially Recall Polyfunctional CD8+ T Cells from Seropositive Asymptomatic Individuals and Protect HLA Transgenic Mice against Ocular Herpes

Science.gov (United States)

Dervillez, Xavier; Qureshi, Huma; Chentoufi, Aziz A.; Khan, Arif A.; Kritzer, Elizabeth; Yu, David C.; Diaz, Oscar R.; Gottimukkala, Chetan; Kalantari, Mina; Villacres, Maria C.; Scarfone, Vanessa M.; McKinney, Denise M.; Sidney, John; Sette, Alessandro; Nesburn, Anthony B.; Wechsler, Steven L.; BenMohamed, Lbachir

2014-01-01

Evidence from C57BL/6 mice suggests that CD8+ T cells, specific to the immunodominant HSV-1 glycoprotein B (gB) H-2b–restricted epitope (gB498–505), protect against ocular herpes infection and disease. However, the possible role of CD8+ T cells, specific to HLA-restricted gB epitopes, in protective immunity seen in HSV-1–seropositive asymptomatic (ASYMP) healthy individuals (who have never had clinical herpes) remains to be determined. In this study, we used multiple prediction algorithms to identify 10 potential HLA-A*02:01–restricted CD8+ T cell epitopes from the HSV-1 gB amino acid sequence. Six of these epitopes exhibited high-affinity binding to HLA-A*02:01 molecules. In 10 sequentially studied HLA-A*02:01–positive, HSV-1–seropositive ASYMP individuals, the most frequent, robust, and polyfunctional CD8+ T cell responses, as assessed by a combination of tetramer, IFN-γ-ELISPOT, CFSE proliferation, CD107a/b cytotoxic degranulation, and multiplex cytokine assays, were directed mainly against epitopes gB342–350 and gB561–569. In contrast, in 10 HLA-A*02:01–positive, HSV-1–seropositive symptomatic (SYMP) individuals (with a history of numerous episodes of recurrent clinical herpes disease) frequent, but less robust, CD8+ T cell responses were directed mainly against nonoverlapping epitopes (gB183–191 and gB441–449). ASYMP individuals had a significantly higher proportion of HSV-gB–specific CD8+ T cells expressing CD107a/b degranulation marker and producing effector cytokines IL-2, IFN-γ, and TNF-α than did SYMP individuals. Moreover, immunization of a novel herpes-susceptible HLA-A*02:01 transgenic mouse model with ASYMP epitopes, but not with SYMP epitopes, induced strong CD8+ T cell–dependent protective immunity against ocular herpes infection and disease. These findings should guide the development of a safe and effective T cell–based herpes vaccine. PMID:24101547

Anthrax lethal factor as an immune target in humans and transgenic mice and the impact of HLA polymorphism on CD4+ T cell immunity.

Science.gov (United States)

Ascough, Stephanie; Ingram, Rebecca J; Chu, Karen K; Reynolds, Catherine J; Musson, Julie A; Doganay, Mehmet; Metan, Gökhan; Ozkul, Yusuf; Baillie, Les; Sriskandan, Shiranee; Moore, Stephen J; Gallagher, Theresa B; Dyson, Hugh; Williamson, E Diane; Robinson, John H; Maillere, Bernard; Boyton, Rosemary J; Altmann, Daniel M

2014-05-01

Bacillus anthracis produces a binary toxin composed of protective antigen (PA) and one of two subunits, lethal factor (LF) or edema factor (EF). Most studies have concentrated on induction of toxin-specific antibodies as the correlate of protective immunity, in contrast to which understanding of cellular immunity to these toxins and its impact on infection is limited. We characterized CD4+ T cell immunity to LF in a panel of humanized HLA-DR and DQ transgenic mice and in naturally exposed patients. As the variation in antigen presentation governed by HLA polymorphism has a major impact on protective immunity to specific epitopes, we examined relative binding affinities of LF peptides to purified HLA class II molecules, identifying those regions likely to be of broad applicability to human immune studies through their ability to bind multiple alleles. Transgenics differing only in their expression of human HLA class II alleles showed a marked hierarchy of immunity to LF. Immunogenicity in HLA transgenics was primarily restricted to epitopes from domains II and IV of LF and promiscuous, dominant epitopes, common to all HLA types, were identified in domain II. The relevance of this model was further demonstrated by the fact that a number of the immunodominant epitopes identified in mice were recognized by T cells from humans previously infected with cutaneous anthrax and from vaccinated individuals. The ability of the identified epitopes to confer protective immunity was demonstrated by lethal anthrax challenge of HLA transgenic mice immunized with a peptide subunit vaccine comprising the immunodominant epitopes that we identified.

Influence of HLA-C Expression Level on HIV Control

Science.gov (United States)

Apps, Richard; Qi, Ying; Carlson, Jonathan M.; Chen, Haoyan; Gao, Xiaojiang; Thomas, Rasmi; Yuki, Yuko; Del Prete, Greg Q.; Goulder, Philip; Brumme, Zabrina L.; Brumme, Chanson J.; John, Mina; Mallal, Simon; Nelson, George; Bosch, Ronald; Heckerman, David; Stein, Judy L.; Soderberg, Kelly A.; Moody, M. Anthony; Denny, Thomas N.; Zeng, Xue; Fang, Jingyuan; Moffett, Ashley; Lifson, Jeffrey D.; Goedert, James J.; Buchbinder, Susan; Kirk, Gregory D.; Fellay, Jacques; McLaren, Paul; Deeks, Steven G.; Pereyra, Florencia; Walker, Bruce; Michael, Nelson L.; Weintrob, Amy; Wolinsky, Steven; Liao, Wilson; Carrington, Mary

2013-01-01

A variant upstream of human leukocyte antigen C (HLA-C) shows the most significant genome-wide effect on HIV control in European Americans and is also associated with the level of HLA-C expression. We characterized the differential cell surface expression levels of all common HLA-C allotypes and tested directly for effects of HLA-C expression on outcomes of HIV infection in 5243 individuals. Increasing HLA-C expression was associated with protection against multiple outcomes independently of individual HLA allelic effects in both African and European Americans, regardless of their distinct HLA-C frequencies and linkage relationships with HLA-B and HLA-A. Higher HLA-C expression was correlated with increased likelihood of cytotoxic T lymphocyte responses and frequency of viral escape mutation. In contrast, high HLA-C expression had a deleterious effect in Crohn’s disease, suggesting a broader influence of HLA expression levels in human disease. PMID:23559252

Activation of ERα signaling differentially modulates IFN-γ induced HLA-class II expression in breast cancer cells.

Directory of Open Access Journals (Sweden)

Ahmed A Mostafa

Full Text Available The coordinate regulation of HLA class II (HLA-II is controlled by the class II transactivator, CIITA, and is crucial for the development of anti-tumor immunity. HLA-II in breast carcinoma is associated with increased IFN-γ levels, reduced expression of the estrogen receptor (ER and reduced age at diagnosis. Here, we tested the hypothesis that estradiol (E₂ and ERα signaling contribute to the regulation of IFN-γ inducible HLA-II in breast cancer cells. Using a panel of established ER⁻ and ER⁺ breast cancer cell lines, we showed that E₂ attenuated HLA-DR in two ER⁺ lines (MCF-7 and BT-474, but not in T47D, while it augmented expression in ER⁻ lines, SK-BR-3 and MDA-MB-231. To further study the mechanism(s, we used paired transfectants: ERα⁺ MC2 (MDA-MB-231 c10A transfected with the wild type ERα gene and ERα⁻ VC5 (MDA-MB-231 c10A transfected with the empty vector, treated or not with E₂ and IFN-γ. HLA-II and CIITA were severely reduced in MC2 compared to VC5 and were further exacerbated by E₂ treatment. Reduced expression occurred at the level of the IFN-γ inducible CIITA promoter IV. The anti-estrogen ICI 182,780 and gene silencing with ESR1 siRNA reversed the E2 inhibitory effects, signifying an antagonistic role for activated ERα on CIITA pIV activity. Moreover, STAT1 signaling, necessary for CIITA pIV activation, and selected STAT1 regulated genes were variably downregulated by E₂ in transfected and endogenous ERα positive breast cancer cells, whereas STAT1 signaling was noticeably augmented in ERα⁻ breast cancer cells. Collectively, these results imply immune escape mechanisms in ERα⁺ breast cancer may be facilitated through an ERα suppressive mechanism on IFN-γ signaling.

Human leukocyte antigen (HLA)-G during pregnancy part I

DEFF Research Database (Denmark)

Klitkou, Louise; Dahl, Mette; Hviid, Thomas Vauvert F

2015-01-01

Human leukocyte antigen (HLA)-G is a class Ib molecule with restricted tissue distribution expressed on trophoblast cells and has been proposed to have immunomodulatory functions during pregnancy. Soluble HLA-G1 (sHLA-G1) can be generated by the shedding of membrane-bound HLA-G molecules; however...... of importance for production of sHLA-G in the mother and child, or it may support the theory that sHLA-G in the pregnant woman and the fetus is partly derived from a "shared organ", the placenta....

Preferential killing of cancer cells and activated human T cells using ZnO nanoparticles

Energy Technology Data Exchange (ETDEWEB)

Hanley, Cory; Layne, Janet; Feris, Kevin; Wingett, Denise [Department of Biological Sciences, Boise State University, Boise, ID 83725 (United States); Punnoose, Alex; Reddy, K M; Coombs, Isaac; Coombs, Andrew [Department of Physics, Boise State University, Boise, ID 83725 (United States)], E-mail: denisewingett@boisestate.edu

2008-07-23

Nanoparticles are increasingly being recognized for their potential utility in biological applications including nanomedicine. Here we examine the response of normal human cells to ZnO nanoparticles under different signaling environments and compare it to the response of cancerous cells. ZnO nanoparticles exhibit a strong preferential ability to kill cancerous T cells ({approx}28-35 x) compared to normal cells. Interestingly, the activation state of the cell contributes toward nanoparticle toxicity, as resting T cells display a relative resistance while cells stimulated through the T cell receptor and CD28 costimulatory pathway show greater toxicity in direct relation to the level of activation. Mechanisms of toxicity appear to involve the generation of reactive oxygen species, with cancerous T cells producing higher inducible levels than normal T cells. In addition, nanoparticles were found to induce apoptosis and the inhibition of reactive oxygen species was found to be protective against nanoparticle induced cell death. The novel findings of cell selective toxicity, towards potential disease causing cells, indicate a potential utility of ZnO nanoparticles in the treatment of cancer and/or autoimmunity.

Preferential killing of cancer cells and activated human T cells using ZnO nanoparticles

International Nuclear Information System (INIS)

Hanley, Cory; Layne, Janet; Feris, Kevin; Wingett, Denise; Punnoose, Alex; Reddy, K M; Coombs, Isaac; Coombs, Andrew

2008-01-01

Nanoparticles are increasingly being recognized for their potential utility in biological applications including nanomedicine. Here we examine the response of normal human cells to ZnO nanoparticles under different signaling environments and compare it to the response of cancerous cells. ZnO nanoparticles exhibit a strong preferential ability to kill cancerous T cells (∼28-35 x) compared to normal cells. Interestingly, the activation state of the cell contributes toward nanoparticle toxicity, as resting T cells display a relative resistance while cells stimulated through the T cell receptor and CD28 costimulatory pathway show greater toxicity in direct relation to the level of activation. Mechanisms of toxicity appear to involve the generation of reactive oxygen species, with cancerous T cells producing higher inducible levels than normal T cells. In addition, nanoparticles were found to induce apoptosis and the inhibition of reactive oxygen species was found to be protective against nanoparticle induced cell death. The novel findings of cell selective toxicity, towards potential disease causing cells, indicate a potential utility of ZnO nanoparticles in the treatment of cancer and/or autoimmunity

HLA-mismatched hematopoietic stem cell tranplantation for pediatric solid tumors

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Andrea Pession

2011-06-01

Full Text Available Even if the overall survival of children with cancer is significantly improved over these decades, the cure rate of high-risk pediatric solid tumors such as neuroblastoma, Ewing’s sarcoma family tumors or rhabdomiosarcoma remain challenging. Autologous hematopoietic stem cell transplantation (HSCT allows chemotherapy dose intensification beyond marrow tolerance and has become a fundamental tool in the multimodal therapeutical approach of these patients. Anyway this procedure does not allow to these children an eventfree survival approaching more than 50% at 5 years. New concepts of allogeneic HSCT and in particular HLA-mismatched HSCT for high risk solid tumors do not rely on escalation of chemo therapy intensity and tumor load reduction but rather on a graft-versus-tumor effect. We here report an experimental study design of HLA-mismatched HSCT for the treatment of pediatric solid tumors and the inherent preliminary results.

Effect of pulsed electron beam on cell killing

International Nuclear Information System (INIS)

Acharya, Santhosh; Joseph, Praveen; Sanjeev, Ganesh; Narayana, Y.; Bhat, N.N.

2009-01-01

The extent of repairable and irreparable damage in a living cell produced by ionizing radiation depends on the quality of the radiation. In the case of sparsely ionizing radiation, the dose rate and the pattern of energy deposition of the radiation are the important physical factors which can affect the amount of damage in living cells. In the present study, radio-sensitive and radioresistive bacteria cells were exposed to 8 MeV pulsed electron beam and the efficiency of cell-killing was investigated to evaluate the Do, the mean lethal dose. The dose to the cell was delivered in micro-second pulses at an instantaneous dose rate of 2.6 x 10 5 Gy s -1 . Fricke dosimeter was used to measure the absorbed dose of electron beam. The results were compared with those of gamma rays. The survival curve of radio-resistive Deinococcus-radiodurans (DR) is found to be sigmoidal and the survival response for radio-sensitive Escherichia-coli (E-coli) is found to be exponential without any shoulder. Comparison of Do values indicate that irradiation with pulsed electron beam resulted in more cell-killing than was observed for gamma irradiation. (author)

Enhanced killing of mammalian cells by radiation combined with m-AMSA

International Nuclear Information System (INIS)

Roberts, P.B.; Millar, B.C.

1980-01-01

m-AMSA is an intercalating agent at present on Phase II trial as a chemotherapeutic drug. A 30min exposure of Chinese hamster (Line V79-753B) cells to submicromolar concentrations of m-AMSA killed 50% of the cells. The survivors had an enhanced sensitivity to radiation-induced cell killing. Depending upon the conditions, m-AMSA enhanced the radiation effect by either a decrease in the survival-curve shoulder or by an increase in slope. m-AMSA may act partly by suppressing the accumulation of sublethal damage but, if so, recovery from damage as measured in split-dose experiments with cells pretreated with the drug is not affected. m-AMSA increased radiation lethality throughout the cell cycle, but a contribution to its radiation effect from selective toxicity to cells in a radioresistant phase of the cell cycle cannot be excluded. Radiation and the drug interacted to give increased cell killing, even when the exposures to each agent were separated in time. It is concluded that m-ASMA may behave like actinomycin D and adriamycin, and enhance clinical radiation responses. In vivo testing to determine the effect of m-AMSA on the therapeutic index is recommended. (author)

Enhanced killing of mammalian cells by radiation combined with m-AMSA

Energy Technology Data Exchange (ETDEWEB)

Roberts, P B; Millar, B C [Institute of Cancer Research, Sutton (UK). Surrey Branch

1980-11-01

m-AMSA is an intercalating agent at present on Phase II trial as a chemotherapeutic drug. A 30 min exposure of Chinese hamster (Line V79-753B) cells to submicromolar concentrations of m-AMSA killed 50% of the cells. The survivors had an enhanced sensitivity to radiation-induced cell killing. Depending upon the conditions, m-AMSA enhanced the radiation effect by either a decrease in the survival-curve shoulder or by an increase in slope. m-AMSA may act partly by suppressing the accumulation of sublethal damage but, if so, recovery from damage as measured in split-dose experiments with cells pretreated with the drug is not affected. m-AMSA increased radiation lethality throughout the cell cycle, but a contribution to its radiation effect from selective toxicity to cells in a radioresistant phase of the cell cycle cannot be excluded. Radiation and the drug interacted to give increased cell killing, even when the exposures to each agent were separated in time. It is concluded that m-ASMA may behave like actinomycin D and adriamycin, and enhance clinical radiation responses. In vivo testing to determine the effect of m-AMSA on the therapeutic index is recommended.

Double suicide genes selectively kill human umbilical vein endothelial cells

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Liu Lunxu

2011-02-01

Full Text Available Abstract Background To construct a recombinant adenovirus containing CDglyTK double suicide genes and evaluate the killing effect of the double suicide genes driven by kinase domain insert containing receptor (KDR promoter on human umbilical vein endothelial cells. Methods Human KDR promoter, Escherichia coli (E. coli cytosine deaminase (CD gene and the herpes simplex virus-thymidine kinase (TK gene were cloned using polymerase chain reaction (PCR. Plasmid pKDR-CDglyTK was constructed with the KDR promoter and CDglyTK genes. A recombinant adenoviral plasmid AdKDR-CDglyTK was then constructed and transfected into 293 packaging cells to grow and harvest adenoviruses. KDR-expressing human umbilical vein endothelial cells (ECV304 and KDR-negative liver cancer cell line (HepG2 were infected with the recombinant adenoviruses at different multiplicity of infection (MOI. The infection rate was measured by green fluorescent protein (GFP expression. The infected cells were cultured in culture media containing different concentrations of prodrugs ganciclovir (GCV and/or 5-fluorocytosine (5-FC. The killing effects were measured using two different methods, i.e. annexin V-FITC staining and terminal transferase-mediated dUTP nick end-labeling (TUNEL staining. Results Recombinant adenoviruses AdKDR-CDglyTK were successfully constructed and they infected ECV304 and HepG2 cells efficiently. The infection rate was dependent on MOI of recombinant adenoviruses. ECV304 cells infected with AdKDR-CDglyTK were highly sensitive to GCV and 5-FC. The cell survival rate was dependent on both the concentration of the prodrugs and the MOI of recombinant adenoviruses. In contrast, there were no killing effects in the HepG2 cells. The combination of two prodrugs was much more effective in killing ECV304 cells than GCV or 5-FC alone. The growth of transgenic ECV304 cells was suppressed in the presence of prodrugs. Conclusion AdKDR-CDglyTK/double prodrog system may be a useful

Dendritic cell mediated delivery of plasmid DNA encoding LAMP/HIV-1 Gag fusion immunogen enhances T cell epitope responses in HLA DR4 transgenic mice.

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Gregory G Simon

2010-01-01

Full Text Available This report describes the identification and bioinformatics analysis of HLA-DR4-restricted HIV-1 Gag epitope peptides, and the application of dendritic cell mediated immunization of DNA plasmid constructs. BALB/c (H-2d and HLA-DR4 (DRA1*0101, DRB1*0401 transgenic mice were immunized with immature dendritic cells transfected by a recombinant DNA plasmid encoding the lysosome-associated membrane protein-1/HIV-1 Gag (pLAMP/gag chimera antigen. Three immunization protocols were compared: 1 primary subcutaneous immunization with 1x10(5 immature dendritic cells transfected by electroporation with the pLAMP/gag DNA plasmid, and a second subcutaneous immunization with the naked pLAMP/gag DNA plasmid; 2 primary immunization as above, and a second subcutaneous immunization with a pool of overlapping peptides spanning the HIV-1 Gag sequence; and 3 immunization twice by subcutaneous injection of the pLAMP/gag DNA plasmid. Primary immunization with pLAMP/gag-transfected dendritic cells elicited the greatest number of peptide specific T-cell responses, as measured by ex vivo IFN-gamma ELISpot assay, both in BALB/c and HLA-DR4 transgenic mice. The pLAMP/gag-transfected dendritic cells prime and naked DNA boost immunization protocol also resulted in an increased apparent avidity of peptide in the ELISpot assay. Strikingly, 20 of 25 peptide-specific T-cell responses in the HLA-DR4 transgenic mice contained sequences that corresponded, entirely or partially to 18 of the 19 human HLA-DR4 epitopes listed in the HIV molecular immunology database. Selection of the most conserved epitope peptides as vaccine targets was facilitated by analysis of their representation and variability in all reported sequences. These data provide a model system that demonstrates a the superiority of immunization with dendritic cells transfected with LAMP/gag plasmid DNA, as compared to naked DNA, b the value of HLA transgenic mice as a model system for the identification and evaluation

Killing effect of peripheral blood mononuclear cells irradiated by γ ray on human gastric cancer MKN-28 cell

International Nuclear Information System (INIS)

Wu Daocheng; Zhang Xianqing; Mu Shijie; Liu Zhongxiang; Xia Aijun; Huang Xiaofeng; An Qunxing

2007-01-01

Objective: To observe the killing effect of peripheral blood mononuclear cells (PBMCs) irradiated by γ ray on cultured human gastric cancer cell line MKN-28. Methods: The experiment were divided into MKN-28 tumor cell control group, PBMCs groups and MKN-28 cells with irradiated or non-irradiated PBMCs co-culture groups. Radidation dosage were from 0.5 to 3 Gy, acridine orange/ethidium bromide (AO/EB) staining were used to observe the kill effect of PBMCs on tumor cells in different period. Results: After culture for 144h, the dead cells of several dosage irradiated PBMCs are much more than those of non-irradiated PBMCs group. At 240 hours of culture, the alive PBMCs deareses in number in both irradiated and non-irradiared groups, but decreases in radiated groups are more obvious. After culture for 72 h in the co-cultured groups, the difference is not evident among all radiation dosage groups. After 96-240 h of co-culture, the killing effect of 0.5-2Gy irradiated PBMCs on tumor cells is very strong, especially in 1Gy group, but the killing effect of PBMCs irradiated by 2.5-3Gy on tumor cells were weaker than that of 0.5-2Gy irradiated groups. At 240 hours co-cultured groups irradiated by 2.5-3Gy, tumor cells still survive and proliferate. Conclusion: Gamma ray irradiation have killing effect to some PBMCs. The cytocidal effect of PBMCs irradiated by 0.5-2Gy on tumor cells were increased. Chemotaxis and cytocidal effect of tumor cells to postirradiated PBMCs were also found. The killing effect of PBMCs irradiated by 2.5 and 3 Gy on tumor cells were restrained. (authors)

A large-scale genetic analysis reveals a strong contribution of the HLA class II region to giant cell arteritis susceptibility.

Science.gov (United States)

Carmona, F David; Mackie, Sarah L; Martín, Jose-Ezequiel; Taylor, John C; Vaglio, Augusto; Eyre, Stephen; Bossini-Castillo, Lara; Castañeda, Santos; Cid, Maria C; Hernández-Rodríguez, José; Prieto-González, Sergio; Solans, Roser; Ramentol-Sintas, Marc; González-Escribano, M Francisca; Ortiz-Fernández, Lourdes; Morado, Inmaculada C; Narváez, Javier; Miranda-Filloy, José A; Beretta, Lorenzo; Lunardi, Claudio; Cimmino, Marco A; Gianfreda, Davide; Santilli, Daniele; Ramirez, Giuseppe A; Soriano, Alessandra; Muratore, Francesco; Pazzola, Giulia; Addimanda, Olga; Wijmenga, Cisca; Witte, Torsten; Schirmer, Jan H; Moosig, Frank; Schönau, Verena; Franke, Andre; Palm, Øyvind; Molberg, Øyvind; Diamantopoulos, Andreas P; Carette, Simon; Cuthbertson, David; Forbess, Lindsy J; Hoffman, Gary S; Khalidi, Nader A; Koening, Curry L; Langford, Carol A; McAlear, Carol A; Moreland, Larry; Monach, Paul A; Pagnoux, Christian; Seo, Philip; Spiera, Robert; Sreih, Antoine G; Warrington, Kenneth J; Ytterberg, Steven R; Gregersen, Peter K; Pease, Colin T; Gough, Andrew; Green, Michael; Hordon, Lesley; Jarrett, Stephen; Watts, Richard; Levy, Sarah; Patel, Yusuf; Kamath, Sanjeet; Dasgupta, Bhaskar; Worthington, Jane; Koeleman, Bobby P C; de Bakker, Paul I W; Barrett, Jennifer H; Salvarani, Carlo; Merkel, Peter A; González-Gay, Miguel A; Morgan, Ann W; Martín, Javier

2015-04-02

We conducted a large-scale genetic analysis on giant cell arteritis (GCA), a polygenic immune-mediated vasculitis. A case-control cohort, comprising 1,651 case subjects with GCA and 15,306 unrelated control subjects from six different countries of European ancestry, was genotyped by the Immunochip array. We also imputed HLA data with a previously validated imputation method to perform a more comprehensive analysis of this genomic region. The strongest association signals were observed in the HLA region, with rs477515 representing the highest peak (p = 4.05 × 10(-40), OR = 1.73). A multivariate model including class II amino acids of HLA-DRβ1 and HLA-DQα1 and one class I amino acid of HLA-B explained most of the HLA association with GCA, consistent with previously reported associations of classical HLA alleles like HLA-DRB1(∗)04. An omnibus test on polymorphic amino acid positions highlighted DRβ1 13 (p = 4.08 × 10(-43)) and HLA-DQα1 47 (p = 4.02 × 10(-46)), 56, and 76 (both p = 1.84 × 10(-45)) as relevant positions for disease susceptibility. Outside the HLA region, the most significant loci included PTPN22 (rs2476601, p = 1.73 × 10(-6), OR = 1.38), LRRC32 (rs10160518, p = 4.39 × 10(-6), OR = 1.20), and REL (rs115674477, p = 1.10 × 10(-5), OR = 1.63). Our study provides evidence of a strong contribution of HLA class I and II molecules to susceptibility to GCA. In the non-HLA region, we confirmed a key role for the functional PTPN22 rs2476601 variant and proposed other putative risk loci for GCA involved in Th1, Th17, and Treg cell function. Copyright © 2015 The American Society of Human Genetics. Published by Elsevier Inc. All rights reserved.

Epitopes recognized by CBV4 responding T cells: effect of type 1 diabetes and associated HLA-DR-DQ haplotypes

International Nuclear Information System (INIS)

Marttila, Jane; Hyoety, Heikki; Naentoe-Salonen, Kirsti; Simell, Olli; Ilonen, Jorma

2004-01-01

The present study aimed at characterizing the epitopes recognized by coxsackievirus B4 (CBV4)-specific T-cell lines established from 23 children with type 1 diabetes (T1D) and 29 healthy children with T1D risk-associated HLA genotypes. Responsiveness to VP1 region was dependent on the specific infection history as 55% of the T-cell lines from donors with neutralizing antibodies to CBV serotypes responded to VP1 peptides compared to none of the T-cell lines from other donors (P = 0.01). The pattern of recognized peptides was dependent of the HLA genotype. Forty-two percent of the T-cell lines from donors carrying the HLA-(DR4)-DQB1*0302 haplotype responded to VP1 peptides 71-80 compared to none of the T-cell lines from donors without this haplotype (P = 0.02). No evidence for the existence of diabetes-specific epitopes was found. Only few epitopes were exclusive recognized by T cells from diabetic children, and in each case only one or two T-cell lines were responding

A leukocyte antigen, Leu-13, is involved in induction of resistance of human cells to x-ray cell killing by interferon-α

International Nuclear Information System (INIS)

Kita, Kazuko; Zhai, Ling; Sugaya, Shigeru; Suzuki, Nobuo

2003-01-01

We previously reported on human interferon (HuIFN)-induced resistance of human cells to X-ray and UV cell killing. In this study, we searched for the genes whose expression is responsible for the resistance, using a PCR-based mRNA differential display method and Northern blotting analysis. RSa cells were used for this analysis, because they show increased resistance to X-ray- and UV-caused cell killing by HuIFN-α treatment prior to irradiation. Messenger RNA expression levels for Leu-13, a leukocyte antigen, were markedly up-regulated in RSa cells after HuIFN-α treatment. Furthermore, pretreatment of RSa cells with antisense oligonucleotides for Leu-13 mRNA resulted in the suppression of the HuIFN-α-induced resistance of the cells to X-ray cell killing, but did not modulate HuIFN-α-induced resistance to UV cell killing. These results suggest that Leu-13 is involved in HuIFN-α-induced resistance of human cells to X-ray cell killing, but not to UV cell killing. (author)

Analysis of the results of allogeneic hematopoietic stem cell transplantation depending on HLA matching of the unrelated donor / recipient pair

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Ye. V. Kuzmich

2015-01-01

Full Text Available HLA matching of the donor / recipient pair is a major factor associated with the outcome of allogeneic stem cell transplantation. In the presentstudy we analyzed the risk of severe acute graft-versus-host disease, graft failure, 2.year overall survival of the patients after allogeneic stem cell transplantation depending on HLA matching of the unrelated donor / recipient pair.

Effects of oxygen and misonidazole on cell transformation and cell killing in C3H 10T1/2 cells by X rays in vitro

International Nuclear Information System (INIS)

Borsa, J.; Sargent, M.D.; Einspenner, M.; Azzam, E.I.; Raaphorst, G.P.

1984-01-01

The effects of oxygen (air) and misonidazole on the transformation and killing of 10T1/2 cells by X rays were examined. The oxygen effect for the cell transformation end point was very similar to that for cell killing. Misonidazole enhanced both cell killing and cell transformation to a similar extent. The enhancement of both end points by misonidazole occurred only in the absence of oxygen during irradiation and was of lesser magnitude than that observed for oxygen. These results demonstrate that the radiation chemical processes leading to cell killing and cell transformation, respectively, are affected similarly by these two enhancers of radiation action. 22 references, 3 figures, 2 tables

Vision-Related Quality of Life in Patients with Inactive HLA-B27-Associated-Spectrum Anterior Uveitis

NARCIS (Netherlands)

Hoeksema, Lisette; Los, Leonoor I.

2016-01-01

We investigated the vision-related quality of life (VR-QOL) in patients with HLA-B27 associated anterior uveitis (AU). The study was conducted in 2012 at the ophthalmology department of the University Medical Center of Groningen. We included AU patients who were HLA-B27 positive and/or were

Can dendritic cells improve whole cancer cell vaccines based on immunogenically killed cancer cells?

Science.gov (United States)

Cicchelero, Laetitia; Denies, Sofie; Devriendt, Bert; de Rooster, Hilde; Sanders, Niek N

2015-01-01

Immunogenic cell death (ICD) offers interesting opportunities in cancer cell (CC) vaccine manufacture, as it increases the immunogenicity of the dead CC. Furthermore, fusion of CCs with dendritic cells (DCs) is considered a superior method for generating whole CC vaccines. Therefore, in this work, we determined in naive mice whether immunogenically killed CCs per se (CC vaccine) elicit an antitumoral immune response different from the response observed when immunogenically killed CCs are associated with DCs through fusion (fusion vaccine) or through co-incubation (co-incubation vaccine). After tumor inoculation, the type of immune response in the prophylactically vaccinated mice differed between the groups. In more detail, fusion vaccines elicited a humoral anticancer response, whereas the co-incubation and CC vaccine mainly induced a cellular response. Despite these differences, all three approaches offered a prophylactic protection against tumor development in the murine mammary carcinoma model. In summary, it can be concluded that whole CC vaccines based on immunogenically killed CCs may not necessarily require association with DCs to elicit a protective anticancer immune response. If this finding can be endorsed in other cancer models, the manufacture of CC vaccines would greatly benefit from this new insight, as production of DC-based vaccines is laborious, time-consuming and expensive. PMID:26587315

CD4+ T cell epitopes of FliC conserved between strains of Burkholderia: implications for vaccines against melioidosis and cepacia complex in cystic fibrosis.

Science.gov (United States)

Musson, Julie A; Reynolds, Catherine J; Rinchai, Darawan; Nithichanon, Arnone; Khaenam, Prasong; Favry, Emmanuel; Spink, Natasha; Chu, Karen K Y; De Soyza, Anthony; Bancroft, Gregory J; Lertmemongkolchai, Ganjana; Maillere, Bernard; Boyton, Rosemary J; Altmann, Daniel M; Robinson, John H

2014-12-15

Burkholderia pseudomallei is the causative agent of melioidosis characterized by pneumonia and fatal septicemia and prevalent in Southeast Asia. Related Burkholderia species are strong risk factors of mortality in cystic fibrosis (CF). The B. pseudomallei flagellar protein FliC is strongly seroreactive and vaccination protects challenged mice. We assessed B. pseudomallei FliC peptide binding affinity to multiple HLA class II alleles and then assessed CD4 T cell immunity in HLA class II transgenic mice and in seropositive individuals in Thailand. T cell hybridomas were generated to investigate cross-reactivity between B. pseudomallei and the related Burkholderia species associated with Cepacia Complex CF. B. pseudomallei FliC contained several peptide sequences with ability to bind multiple HLA class II alleles. Several peptides were shown to encompass strong CD4 T cell epitopes in B. pseudomallei-exposed individuals and in HLA transgenic mice. In particular, the p38 epitope is robustly recognized by CD4 T cells of seropositive donors across diverse HLA haplotypes. T cell hybridomas against an immunogenic B. pseudomallei FliC epitope also cross-reacted with orthologous FliC sequences from Burkholderia multivorans and Burkholderia cenocepacia, important pathogens in CF. Epitopes within FliC were accessible for processing and presentation from live or heat-killed bacteria, demonstrating that flagellin enters the HLA class II Ag presentation pathway during infection of macrophages with B. cenocepacia. Collectively, the data support the possibility of incorporating FliC T cell epitopes into vaccination programs targeting both at-risk individuals in B. pseudomallei endemic regions as well as CF patients. Copyright © 2014 by The American Association of Immunologists, Inc.

A Lipopeptide Facilitate Induction of Mycobacterium leprae Killing in Host Cells

Science.gov (United States)

Maeda, Yumi; Tamura, Toshiki; Fukutomi, Yasuo; Mukai, Tetsu; Kai, Masanori; Makino, Masahiko

2011-01-01

Little is known of the direct microbicidal activity of T cells in leprosy, so a lipopeptide consisting of the N-terminal 13 amino acids lipopeptide (LipoK) of a 33-kD lipoprotein of Mycobacterium leprae, was synthesized. LipoK activated M. leprae infected human dendritic cells (DCs) to induce the production of IL-12. These activated DCs stimulated autologous CD4+ or CD8+ T cells towards type 1 immune response by inducing interferon-gamma secretion. T cell proliferation was also evident from the CFSE labeling of target CD4+ or CD8+ T cells. The direct microbicidal activity of T cells in the control of M. leprae multiplication is not well understood. The present study showed significant production of granulysin, granzyme B and perforin from these activated CD4+ and CD8+ T cells when stimulated with LipoK activated, M. leprae infected DCs. Assessment of the viability of M. leprae in DCs indicated LipoK mediated T cell-dependent killing of M. leprae. Remarkably, granulysin as well as granzyme B could directly kill M. leprae in vitro. Our results provide evidence that LipoK could facilitate M. leprae killing through the production of effector molecules granulysin and granzyme B in T cells. PMID:22132248

HIV control through a single nucleotide on the HLA-B locus

DEFF Research Database (Denmark)

Kløverpris, Henrik N; Harndahl, Mikkel; Leslie, Alasdair J

2012-01-01

Genetic variation within the HLA-B locus has the strongest impact on HIV disease progression of any polymorphisms within the human genome. However, identifying the exact mechanism involved is complicated by several factors. HLA-Bw4 alleles provide ligands for NK cells and for CD8 T cells, and str......Genetic variation within the HLA-B locus has the strongest impact on HIV disease progression of any polymorphisms within the human genome. However, identifying the exact mechanism involved is complicated by several factors. HLA-Bw4 alleles provide ligands for NK cells and for CD8 T cells......:02, which differ by only a single amino acid. Crucially, they occur primarily on identical HLA class I haplotypes and, as Bw6 alleles, do not act as NK cell ligands and are therefore largely unconfounded by other genetic factors. We show that in an outbred cohort (n = 2,093) of HIV C......-clade-infected individuals, a single amino acid change at position 9 of the HLA-B molecule critically affects peptide binding and significantly alters the cytotoxic T lymphocyte (CTL) epitopes targeted, measured directly ex vivo by gamma interferon (IFN-γ) enzyme-linked immunospot (ELISPOT) assay (P = 2 × 10...

Protection against hyperthermic cell killing by alanine

International Nuclear Information System (INIS)

Cunningham, A.; Henle, K.J.; Moss, A.J.; Nagle, W.A.

1987-01-01

Compounds capable of protecting cells against hyperthermia may provide new insights into potential mechanisms of thermotolerance and cellular heat death. The authors characterized heat protection by alanine and related compounds as a function of concentration, temperature and preincubation time. Alanine was added either to complete medium or to HBSS before hyperthermia. Maximal heat protection required 3 hr, 37 0 ; longer preincubation intervals resulted in lower levels of protection. Addition of alanine to medium after hyperthermia had no protective effect. Protection was concentration dependent with a 20- or 200-fold increase in cell survival after 40 min, 45 0 C at 60 mM in medium or in HBSS, respectively. Higher alanine concentrations up to 120mM did not significantly increase heat protection. A 45 0 -heat survival curve showed that 100mM alanine increased the D/sub q/ by approx. 12 min with little change in the D/sub o/. Hyperthermia of 1 hr at temperatures between 42 0 and 45 0 indicated that 100mM alanine shifted the isotoxic temperature by 0.5 Celsius degrees. Polymers of either L or D,L alanine and related compounds, like pyruvate, also protected cells against heat killing. These results indicate that heat protection by alanine shows characteristics that are not shared by polyhydroxy compounds

Potentiation of radiation-induced cell kill by synthetic metalloporphyrins

International Nuclear Information System (INIS)

O'Hara, J.A.; Douple, E.B.; Abrams, M.J.; Picker, D.J.; Giandomenico, C.M.; Vollano, J.F.

1989-01-01

The effects of the combination of several meso-substituted, water soluble metalloporphyrins with ionizing radiation on hypoxic and oxic monolayers of Chinese hamster fibroblast (V79N) cells were studied. The metalloporphyrins tested included a series of cationic metalloporphyrins complexed with Co(III), Zn(II), Fe(III), Cu(II), Pd(II) or Mn(III) and a series of anionic porphyrins chelated with Co(III), Fe(III), Cu(II), Rh(III), Mn(III) or Sn(IV). Both cationic and anionic free porphyrins were also tested. Cationic ligands were tetrakis(4N-methylpyridyl)porphine [TMPyP], tetrakis(4N-trimethylamino phenyl)porphine [TMAP], tetrakis(4N-butylpyridyl)porphine [TBPyP] and tetrakis(3N-methylpyridyl)porphine [3TMPyP]. Anionic ligands tested were tetrakis(4-sulfonato phenyl)porphine [TPPS], tetrakis(biphenyl)porphine sulfonate [TBPS] and tetrakis(4-carboxyphenyl)porphine [TCPP]. SER calculated from survival curves and SFR from one radiation dose were used to assess the relative effectiveness of this class as non-cytotoxic hypoxic and oxic cell-kill potentiators. Comparisons were made at 100 microM, which was essentially non-toxic (greater than 70% survival) for all porphyrins tested except for Co[TMPyP] (approximately 50% survival after 1 hour at 37 degrees C under oxic conditions). The greatest effects on radiation-induced cell kill were achieved with Co[TPPS] and Co[TMPyP] with SER values of 2.3 and 2.4 respectively. Porphyrin analogs with no coordinated metal were found to be less active than the same compound with metal. The overall charge on the molecule did not systematically relate to the biological activity of the compounds tested

Glucocorticoids and Polyamine Inhibitors Synergize to Kill Human Leukemic CEM Cells1

Science.gov (United States)

Miller, Aaron L; Johnson, Betty H; Medh, Rheem D; Townsend, Courtney M; Thompson, E Brad

2002-01-01

Abstract Glucocorticoids are well-known apoptotic agents in certain classes of lymphoid cell malignancies. Reduction of intracellular polyamine levels by use of inhibitors that block polyamine synthesis slows or inhibits growth of many cells in vitro. Several such inhibitors have shown efficacy in clinical trials, though the toxicity of some compounds has limited their usefulness. We have tested the effects of combinations of the glucocorticoid dexamethasone (Dex) and two polyamine inhibitors, difluoromethylornithine (DFMO) and methyl glyoxal bis guanylhydrazone (MGBG), on the clonal line of human acute lymphoblastic leukemia cells, CEM-C7-14. Dex alone kills these cells, though only after a delay of at least 24 hours. We also evaluated a partially glucocorticoid-resistant c-Myc-expressing CEM-C7-14 clone. We show that Dex downregulates ornithine decarboxylase (ODC), the rate-limiting enzyme in polyamine synthesis. Pretreatment with the ODC inhibitor DFMO, followed by addition of Dex, enhances steroid-evoked kill slightly. The combination of pretreatment with sublethal concentrations of both DFMO and the inhibitor of S-adenosylmethionine decarboxylase, MGBG, followed by addition of Dex, results in strong synergistic cell kill. Both the rapidity and extent of cell kill are enhanced compared to the effects of Dex alone. These results suggest that use of such combinations in vivo may result in apoptosis of malignant cells with lower overall toxicity. PMID:11922393

Expression pattern of immunosurveillance-related antigen in adult T cell leukaemia/lymphoma.

Science.gov (United States)

Asano, Naoko; Miyoshi, Hiroaki; Kato, Takeharu; Shimono, Joji; Yoshida, Noriaki; Kurita, Daisuke; Sasaki, Yuya; Kawamoto, Keisuke; Ohshima, Koichi; Seto, Masao

2018-05-01

Adult T cell leukaemia/lymphoma (ATLL) is an aggressive malignancy with a poor prognosis. Human leucocyte antigen (HLA) and β2 microglobulin (β2M) serve as key molecules in tumour immunity, and their expression is reduced frequently in tumour cells. Programmed cell death (PD)-1/PD-ligand1 (PD-L1) interactions play a role in escape of tumour cells from T cell immunity. Therefore, this study aimed to determine the clinicopathological relevance of HLA and β2M expressions in ATLL cells and PD-L1 expression in lymphoma or stromal cells and predict the overall survival of patients with ATLL. We analysed a total of 123 biopsy samples from patients newly diagnosed with ATLL by using immunohistochemical analysis. Of the patients enrolled, 91 (74%) were positive for HLA (in cell membrane, 60 patients), 89 (72%) were positive for β2M (in cell membrane, 54 patients) and 48 (39%) were positive for both HLA and β2M in the cell membrane (HLA m+ β2M m+ ). No significant clinical differences other than prognosis were found between the HLA m+ β2M m+ group and the other groups. Immunophenotypical evaluation revealed significantly higher rates of CD30-positive lymphoma cells (P = 0.003) and PD-L1-positive stromal cells in microenvironments (miPD-L1 high ) (P = 0.011) of the HLA m+ β2M m+ group than in the other groups. The HLA m+ β2M m+ group had a significantly better prognosis that the other groups (P = 0.0096), and patients showing HLA m+ β2M m+ with miPD-L1 high had the most favourable prognosis among all groups. The membranous expression of HLA and β2M is likely to reflect the immune response and would be useful to predict prognosis before starting ATLL therapy. © 2018 John Wiley & Sons Ltd.

Predicting HLA class I non-permissive amino acid residues substitutions.

Directory of Open Access Journals (Sweden)

T Andrew Binkowski

Full Text Available Prediction of peptide binding to human leukocyte antigen (HLA molecules is essential to a wide range of clinical entities from vaccine design to stem cell transplant compatibility. Here we present a new structure-based methodology that applies robust computational tools to model peptide-HLA (p-HLA binding interactions. The method leverages the structural conservation observed in p-HLA complexes to significantly reduce the search space and calculate the system's binding free energy. This approach is benchmarked against existing p-HLA complexes and the prediction performance is measured against a library of experimentally validated peptides. The effect on binding activity across a large set of high-affinity peptides is used to investigate amino acid mismatches reported as high-risk factors in hematopoietic stem cell transplantation.

HL-A27 and anterior uveitis.

Science.gov (United States)

Woodrow, J C; Mapstone, R; Anderson, J; Usher, N

1975-09-01

HL-A types were determined in 90 successive patients with non-granulomatous uveitis. Fifty-one were HL-A27 positive (55.7%) compared to 8.2% of controls. Of 16 patients with ankylosing spondylitis, 13 were HL-A27 positive, as were two patients with a history of Reiter's syndrome. Twenty-eight patients were HL-A27 positive but had no evidence of rheumatic disease. The findings are discussed in relation to the possible pathogenesis of uveitis.

CTL lysis: there is a hyperbolic relation of killing rate to exocytosable granzyme A for highly cytotoxic murine cytotoxic T lymphocytes.

Science.gov (United States)

Poe, M; Wu, J K; Talento, A; Koo, G C

1996-06-10

The lysis of susceptible targets by efficient cytotoxic T lymphocytes (CTL) increases both with time and with the ratio of CTL to target. Simple methods for calculating a killing rate constant from the time dependence of killing and for calculating the relation of the killing rate constant to the concentration of exocytosable granzyme A are given. Application of these methods to the killing of target cells by the highly efficient mouse CTL AR1 is presented. AR1 needed granzyme A for efficient killing. AR1 contained sufficient exocytosable granzyme A to kill at about 80% of the rate possible at infinite exocytosable granzyme A.

Oligoclonal band phenotypes in MS differ in their HLA class II association, while specific KIR ligands at HLA class I show association to MS in general

DEFF Research Database (Denmark)

Gustavsen, Marte W; Viken, Marte K; Celius, Elisabeth G

2014-01-01

Multiple sclerosis (MS) patients have been reported to have different HLA class II allele profiles depending on oligoclonal bands (OCBs) in the cerebrospinal fluid, but HLA class I alleles and killer cell immunoglobulin-like receptor (KIR) ligands have not been studied. We investigated the associ......Multiple sclerosis (MS) patients have been reported to have different HLA class II allele profiles depending on oligoclonal bands (OCBs) in the cerebrospinal fluid, but HLA class I alleles and killer cell immunoglobulin-like receptor (KIR) ligands have not been studied. We investigated...

HLA-inferred extended haplotype disparity level is more relevant than the level of HLA mismatch alone for the patients survival and GvHD in T cell-replate hematopoietic stem cell transplantation from unrelated donor.

Science.gov (United States)

Nowak, Jacek; Nestorowicz, Klaudia; Graczyk-Pol, Elzbieta; Mika-Witkowska, Renata; Rogatko-Koros, Marta; Jaskula, Emilia; Koscinska, Katarzyna; Madej, Sylwia; Tomaszewska, Agnieszka; Nasilowska-Adamska, Barbara; Szczepinski, Andrzej; Halaburda, Kazimierz; Dybko, Jaroslaw; Kuliczkowski, Kazimierz; Czerw, Tomasz; Giebel, Sebastian; Holowiecki, Jerzy; Baranska, Malgorzata; Pieczonka, Anna; Wachowiak, Jacek; Czyz, Anna; Gil, Lidia; Lojko-Dankowska, Anna; Komarnicki, Mieczyslaw; Bieniaszewska, Maria; Kucharska, Agnieszka; Hellmann, Andrzej; Gronkowska, Anna; Jedrzejczak, Wieslaw W; Markiewicz, Miroslaw; Koclega, Anna; Kyrcz-Krzemien, Slawomira; Mielcarek, Monika; Kalwak, Krzysztof; Styczynski, Jan; Wysocki, Mariusz; Drabko, Katarzyna; Wojcik, Beata; Kowalczyk, Jerzy; Gozdzik, Jolanta; Pawliczak, Daria; Gwozdowicz, Slawomir; Dziopa, Joanna; Szlendak, Urszula; Witkowska, Agnieszka; Zubala, Marta; Gawron, Agnieszka; Warzocha, Krzysztof; Lange, Andrzej

2018-06-01

Serious risks in unrelated hematopoietic stem cell transplantation (HSCT) including graft versus host disease (GvHD) and mortality are associated with HLA disparity between donor and recipient. The increased risks might be dependent on disparity in not-routinely-tested multiple polymorphisms in genetically dense MHC region, being organized in combinations of two extended MHC haplotypes (Ehp). We assessed the clinical role of donor-recipient Ehp disparity levels in N = 889 patients by the population-based detection of HLA allele phase mismatch. We found increased GvHD incidences and mortality rates with increasing Ehp mismatch level even with the same HLA mismatch level. In multivariate analysis HLA mismatch levels were excluded from models and Ehp disparity level remained independent prognostic factor for high grade acute GvHD (p = 0.000037, HR = 10.68, 95%CI 5.50-32.5) and extended chronic GvHD (p < 0.000001, HR = 15.51, CI95% 5.36-44.8). In group with single HLA mismatch, patients with double Ehp disparity had worse 5-year overall survival (45% vs. 56%, p = 0.00065, HR = 4.05, CI95% 1.69-9.71) and non-relapse mortality (40% vs. 31%, p = 0.00037, HR = 5.63, CI95% 2.04-15.5) than patients with single Ehp disparity. We conclude that Ehp-linked factors contribute to the high morbidity and mortality in recipients given HLA-mismatched unrelated transplant and Ehp matching should be considered in clinical HSCT. Copyright © 2018. Published by Elsevier Inc.

Charting improvements in US registry HLA typing ambiguity using a typing resolution score.

Science.gov (United States)

Paunić, Vanja; Gragert, Loren; Schneider, Joel; Müller, Carlheinz; Maiers, Martin

2016-07-01

Unrelated stem cell registries have been collecting HLA typing of volunteer bone marrow donors for over 25years. Donor selection for hematopoietic stem cell transplantation is based primarily on matching the alleles of donors and patients at five polymorphic HLA loci. As HLA typing technologies have continually advanced since the beginnings of stem cell transplantation, registries have accrued typings of varied HLA typing ambiguity. We present a new typing resolution score (TRS), based on the likelihood of self-match, that allows the systematic comparison of HLA typings across different methods, data sets and populations. We apply the TRS to chart improvement in HLA typing within the Be The Match Registry of the United States from the initiation of DNA-based HLA typing to the current state of high-resolution typing using next-generation sequencing technologies. In addition, we present a publicly available online tool for evaluation of any given HLA typing. This TRS objectively evaluates HLA typing methods and can help define standards for acceptable recruitment HLA typing. Copyright © 2016 American Society for Histocompatibility and Immunogenetics. Published by Elsevier Inc. All rights reserved.

HLA-A*0201-restricted CTL epitope of a novel osteosarcoma antigen, papillomavirus binding factor

Directory of Open Access Journals (Sweden)

Tsukahara Tomohide

2009-06-01

Full Text Available Abstract Background To develop peptide-based immunotherapy for osteosarcoma, we previously identified papillomavirus binding factor (PBF as a CTL-defined osteosarcoma antigen in the context of HLA-B55. However, clinical application of PBF-based immunotherapy requires identification of naturally presented CTL epitopes in osteosarcoma cells in the context of more common HLA molecules such as HLA-A2. Methods Ten peptides with the HLA-A*0201 binding motif were synthesized from the amino acid sequence of PBF according to the BIMAS score and screened with an HLA class I stabilization assay. The frequency of CTLs recognizing the selected PBF-derived peptide was determined in peripheral blood of five HLA-A*0201+ patients with osteosarcoma using limiting dilution (LD/mixed lymphocyte peptide culture (MLPC followed by tetramer-based frequency analysis. Attempts were made to establish PBF-specific CTL clones from the tetramer-positive CTL pool by a combination of limiting dilution and single-cell sorting. The cytotoxicity of CTLs was assessed by 51Cr release assay. Results Peptide PBF A2.2 showed the highest affinity to HLA-A*0201. CD8+ T cells reacting with the PBF A2.2 peptide were detected in three of five patients at frequencies from 2 × 10-7 to 5 × 10-6. A tetramer-positive PBF A2.2-specific CTL line, 5A9, specifically lysed allogeneic osteosarcoma cell lines that expressed both PBF and either HLA-A*0201 or HLA-A*0206, autologous tumor cells, and T2 pulsed with PBF A2.2. Five of 12 tetramer-positive CTL clones also lysed allogeneic osteosarcoma cell lines expressing both PBF and either HLA-A*0201 or HLA-A*0206 and T2 pulsed with PBF A2.2. Conclusion These findings indicate that PBF A2.2 serves as a CTL epitope on osteosarcoma cells in the context of HLA-A*0201, and potentially, HLA-A*0206. This extends the availability of PBF-derived therapeutic peptide vaccines for patients with osteosarcoma.

Direct analysis of viral-specific CD8+ T cells with soluble HLA-A2/Tax11-19 tetramer complexes in patients with human T cell lymphotropic virus-associated myelopathy.

Science.gov (United States)

Bieganowska, K; Höllsberg, P; Buckle, G J; Lim, D G; Greten, T F; Schneck, J; Altman, J D; Jacobson, S; Ledis, S L; Hanchard, B; Chin, J; Morgan, O; Roth, P A; Hafler, D A

1999-02-01

Human T cell lymphotropic virus-I (HTLV-I)-associated myelopathy is a slowly progressive neurologic disease characterized by inflammatory infiltrates in the central nervous system accompanied by clonal expansion of HTLV-I-reactive CD8+ T-cells. In patients carrying the HLA-A2 allele, the immune response is primarily directed to the Tax11-19 peptide. The frequency, activation state, and TCR usage of HLA-A2/Tax11-19 binding T cells in patients with HTLV-I-associated myelopathy was determined using MHC class I tetramers loaded with the Tax11-19 peptide. Circulating Tax11-19-reactive T cells were found at very high frequencies, approaching 1:10 circulating CD8+ T cells. T cells binding HLA-A2/Tax11-19 consisted of heterogeneous populations expressing different chemokine receptors and the IL-2R beta-chain but not the IL-2R alpha-chain. Additionally, Tax11-19-reactive CD8+ T cells used one predominant TCR Vbeta-chain for the recognition of the HLA-A2/Tax11-19 complex. These data provide direct evidence for high frequencies of circulating Tax11-19-reactive CD8+ T cells in patients with HTLV-I-associated myelopathy.

Characterization of cell lysis in Pseudomonas putida induced upon expression of heterologous killing genes

DEFF Research Database (Denmark)

Ronchel, M.C.; Molina, L.; Witte, A.

1998-01-01

Active biological containment systems are based on the controlled expression of killing genes. These systems are of interest for the Pseudomonadaceae because of the potential applications of these microbes as bioremediation agents and biopesticides, The physiological effects that lead to cell dea...... protein was the killing agent. In both cases, cell death occurred as a result of impaired respiration, altered membrane permeability, and the release of some cytoplasmic contents to the extracellular medium.......Active biological containment systems are based on the controlled expression of killing genes. These systems are of interest for the Pseudomonadaceae because of the potential applications of these microbes as bioremediation agents and biopesticides, The physiological effects that lead to cell death......, respectively. Expression of the killing genes is controlled by the LacI protein, whose expression is initiated from the XylS-dependent Pm promoter. Under induced conditions, killing of P. putida CMC12 cells mediated by phi X174 lysis protein E was faster than that observed for P. putida CMC4, for which the Gef...

Monoclonal TCR-redirected tumor cell killing.

Science.gov (United States)

Liddy, Nathaniel; Bossi, Giovanna; Adams, Katherine J; Lissina, Anna; Mahon, Tara M; Hassan, Namir J; Gavarret, Jessie; Bianchi, Frayne C; Pumphrey, Nicholas J; Ladell, Kristin; Gostick, Emma; Sewell, Andrew K; Lissin, Nikolai M; Harwood, Naomi E; Molloy, Peter E; Li, Yi; Cameron, Brian J; Sami, Malkit; Baston, Emma E; Todorov, Penio T; Paston, Samantha J; Dennis, Rebecca E; Harper, Jane V; Dunn, Steve M; Ashfield, Rebecca; Johnson, Andy; McGrath, Yvonne; Plesa, Gabriela; June, Carl H; Kalos, Michael; Price, David A; Vuidepot, Annelise; Williams, Daniel D; Sutton, Deborah H; Jakobsen, Bent K

2012-06-01

T cell immunity can potentially eradicate malignant cells and lead to clinical remission in a minority of patients with cancer. In the majority of these individuals, however, there is a failure of the specific T cell receptor (TCR)–mediated immune recognition and activation process. Here we describe the engineering and characterization of new reagents termed immune-mobilizing monoclonal TCRs against cancer (ImmTACs). Four such ImmTACs, each comprising a distinct tumor-associated epitope-specific monoclonal TCR with picomolar affinity fused to a humanized cluster of differentiation 3 (CD3)-specific single-chain antibody fragment (scFv), effectively redirected T cells to kill cancer cells expressing extremely low surface epitope densities. Furthermore, these reagents potently suppressed tumor growth in vivo. Thus, ImmTACs overcome immune tolerance to cancer and represent a new approach to tumor immunotherapy.

ONC201 kills breast cancer cells in vitro by targeting mitochondria.

Science.gov (United States)

Greer, Yoshimi Endo; Porat-Shliom, Natalie; Nagashima, Kunio; Stuelten, Christina; Crooks, Dan; Koparde, Vishal N; Gilbert, Samuel F; Islam, Celia; Ubaldini, Ashley; Ji, Yun; Gattinoni, Luca; Soheilian, Ferri; Wang, Xiantao; Hafner, Markus; Shetty, Jyoti; Tran, Bao; Jailwala, Parthav; Cam, Maggie; Lang, Martin; Voeller, Donna; Reinhold, William C; Rajapakse, Vinodh; Pommier, Yves; Weigert, Roberto; Linehan, W Marston; Lipkowitz, Stanley

2018-04-06

We report a novel mechanism of action of ONC201 as a mitochondria-targeting drug in cancer cells. ONC201 was originally identified as a small molecule that induces transcription of TNF-related apoptosis-inducing ligand (TRAIL) and subsequently kills cancer cells by activating TRAIL death receptors. In this study, we examined ONC201 toxicity on multiple human breast and endometrial cancer cell lines. ONC201 attenuated cell viability in all cancer cell lines tested. Unexpectedly, ONC201 toxicity was not dependent on either TRAIL receptors nor caspases. Time-lapse live cell imaging revealed that ONC201 induces cell membrane ballooning followed by rupture, distinct from the morphology of cells undergoing apoptosis. Further investigation found that ONC201 induces phosphorylation of AMP-dependent kinase and ATP loss. Cytotoxicity and ATP depletion were significantly enhanced in the absence of glucose, suggesting that ONC201 targets mitochondrial respiration. Further analysis indicated that ONC201 indirectly inhibits mitochondrial respiration. Confocal and electron microscopic analysis demonstrated that ONC201 triggers mitochondrial structural damage and functional impairment. Moreover, ONC201 decreased mitochondrial DNA (mtDNA). RNAseq analysis revealed that ONC201 suppresses expression of multiple mtDNA-encoded genes and nuclear-encoded mitochondrial genes involved in oxidative phosphorylation and other mitochondrial functions. Importantly, fumarate hydratase deficient cancer cells and multiple cancer cell lines with reduced amounts of mtDNA were resistant to ONC201. These results indicate that cells not dependent on mitochondrial respiration are ONC201-resistant. Our data demonstrate that ONC201 kills cancer cells by disrupting mitochondrial function and further suggests that cancer cells that are dependent on glycolysis will be resistant to ONC201.

HLA polymorphisms in Sindhi community in Mumbai, India.

Science.gov (United States)

Chhaya, S; Desai, S; Saranath, D

2010-10-01

Indian population is an amalgamation of various ethnicities, cultural and linguistic diversities, primarily due to marriages within a community. HLA-A, B and DRB1 alleles and haplotype frequencies were investigated in the Sindhi and compared with Marathi, Gujarati and North Indian population from Mumbai. This work is a part of a larger effort aimed at analysis of the HLA profile of diverse Indian ethnics to establish an umbilical cord stem cell panel in India. HLA polymorphisms at the HLA-A, B and DRB1 loci were determined in 413 cord blood samples by the molecular method of polymerase chain reaction using sequence-specific primer amplification. The most frequent alleles included A*01, A*02, A*11 and A*24 at A locus, B*35 and B*40 at B locus and DRB1*07 and DRB1*15 in all the four groups, although the frequency fluctuated in individual communities. HLA-DRB1*03 was significantly high (P < 0.05) in the Sindhi. Phylogenetic association using neighbour-joining tree, based on DA genetic distances for HLA-A and HLA-B alleles, indicated that the Sindhis cluster with North Indian and Pakistan Sindhi. The three locus haplotype analysis revealed that A*02-B*40-DRB1*15 and A*33-B*44-DRB1*07 were common haplotypes in all the groups. The three locus haplotypes found suggest an influence from Caucasian and Oriental populations. The data will be useful in developing an umbilical cord stem cell panel in India. The results will have clinical implications in unrelated umbilical cord stem cell for transplantation in India. © 2010 Blackwell Publishing Ltd.

A novel bispecific antibody, S-Fab, induces potent cancer cell killing.

Science.gov (United States)

Li, Li; He, Ping; Zhou, Changhua; Jing, Li; Dong, Bin; Chen, Siqi; Zhang, Ning; Liu, Yawei; Miao, Ji; Wang, Zhong; Li, Qing

2015-01-01

Bispecific antibodies that engage immune cells to kill cancer cells have been actively studied in cancer immunotherapy. In this study, we present a novel bispecific format, S-Fab, fabricated by linking a single-domain anti-carcinoembryonic antigen VHH to a conventional anti-CD3 Fab. In contrast to most bispecific antibodies, the S-Fab bispecific antibody can be efficiently expressed and purified from bacteria. The purified S-Fab is stable in serum and is able to recruit T cells to drive potent cancer cell killing. In xenograft models, the S-Fab antibody suppresses tumor growth in the presence of human immune cells. Our study suggested that the bispecific S-Fab format can be applied to a wide range of immunotherapies.

Vesicle-associated membrane protein 7 (VAMP-7) is essential for target cell killing in a natural killer cell line

International Nuclear Information System (INIS)

Marcet-Palacios, Marcelo; Odemuyiwa, Solomon O.; Coughlin, Jason J.; Garofoli, Daniella; Ewen, Catherine; Davidson, Courtney E.; Ghaffari, Mazyar; Kane, Kevin P.; Lacy, Paige; Logan, Michael R.; Befus, A. Dean; Bleackley, R. Chris; Moqbel, Redwan

2008-01-01

Natural killer cells recognize and induce apoptosis in foreign, transformed or virus-infected cells through the release of perforin and granzymes from secretory lysosomes. Clinically, NK-cell mediated killing is a major limitation to successful allo- and xenotransplantation. The molecular mechanisms that regulate the fusion of granzyme B-containing secretory lysosomes to the plasma membrane in activated NK cells, prior to target cell killing, are not fully understood. Using the NK cell line YT-Indy as a model, we have investigated the expression of SNAP REceptors (SNAREs), both target (t-) and vesicular (v-) SNAREs, and their function in granzyme B-mediated target cell killing. Our data showed that YT-Indy cells express VAMP-7 and SNAP-23, but not VAMP-2. VAMP-7 was associated with granzyme B-containing lysosomal granules. Using VAMP-7 small interfering RNA (siRNA), we successfully knocked down the expression of VAMP-7 protein in YT-Indy to less than 10% of untreated cells in 24 h. VAMP7-deficient YT-Indy cells activated via co-culture with Jurkat cells released <1 ng/mL of granzyme B, compared to 1.5-2.5 μg/mL from controls. Using Jurkat cells as targets, we showed a 7-fold reduction in NK cell-mediated killing by VAMP-7 deficient YT-Indy cells. Our results show that VAMP-7 is a crucial component of granzyme B release and target cell killing in the NK cell line YT-Indy. Thus, targeting VAMP-7 expression specifically with siRNA, following transplantation, may be a viable strategy for preventing NK cell-mediated transplant rejection, in vivo

Cytotoxic T-lymphocyte clones, established by stimulation with the HLA-A2 binding p5365-73 wild type peptide loaded on dendritic cells In vitro, specifically recognize and lyse HLA-A2 tumour cells overexpressing the p53 protein

DEFF Research Database (Denmark)

Barfoed, Annette Malene; Petersen, T R; Kirkin, A F

2000-01-01

of recognizing p53 derived wild type (self) peptides. Furthermore, the capacity of R9V specific T cell clones to exert HLA restricted cytotoxicity, argues that the R9V peptide is naturally presented on certain cancer cells. This supports the view that p53 derived wild type peptides might serve as candidate......Mutations in the tumour suppressor gene p53 are among the most frequent genetic alterations in human malignancies, often associated with an accumulation of the p53 protein in the cytoplasm. We have generated a number of cytotoxic T lymphocyte (CTL) clones that specifically recognize the HLA-A*0201...

HLA-B27 subtypes among the Chukotka native groups

Energy Technology Data Exchange (ETDEWEB)

Krylov, M.Y.; Alexeeva, L.I.; Erdesz, S.; Benevolenskaya, L.I. [Akademiya Meditsinskikh Nauk SSSR, Moscow (Russian Federation). Inst. Revmatizma; Reveille, J.D.; Arnett, F.C. [Texas Univ., Houston, TX (United States). Health Science Center

1995-12-31

The purpose of this study was to assess the relative frequency of the known HLA-B27 subtypes in HLA-B27 positive Chukotka natives, which have higher frequencies of HLA-B27 (to 40%) and spondylarthropathies (to 2%) than the Russian Caucasian population. Using oligotyping of the polymerase-chain reaction amplified second and third exons of the HLA-B27 gene in 86 DNA samples from HLA-B27 positive individuals were successfully typed. All had HLA-B*2705, including 4 patients with Reiter`s syndrome and 5 with ankylosing spondyloarthritis, except one Eskimo who had HLA-B*2702. None had HLA-B*2704, a frequent subtype in Orientals. With respect to HLA-B27 subtypes the indigenous populations from the eastern part of the Chukotka Peninsula are genetically more closely related to Caucasians than to Orientals. (author). 18 refs, 1 fig., 2 tabs.

HLA-B27 subtypes among the Chukotka native groups

International Nuclear Information System (INIS)

Krylov, M.Y.; Alexeeva, L.I.; Erdesz, S.; Benevolenskaya, L.I.; Reveille, J.D.; Arnett, F.C.

1995-01-01

The purpose of this study was to assess the relative frequency of the known HLA-B27 subtypes in HLA-B27 positive Chukotka natives, which have higher frequencies of HLA-B27 (to 40%) and spondylarthropathies (to 2%) than the Russian Caucasian population. Using oligotyping of the polymerase-chain reaction amplified second and third exons of the HLA-B27 gene in 86 DNA samples from HLA-B27 positive individuals were successfully typed. All had HLA-B*2705, including 4 patients with Reiter's syndrome and 5 with ankylosing spondyloarthritis, except one Eskimo who had HLA-B*2702. None had HLA-B*2704, a frequent subtype in Orientals. With respect to HLA-B27 subtypes the indigenous populations from the eastern part of the Chukotka Peninsula are genetically more closely related to Caucasians than to Orientals. (author). 18 refs, 1 fig., 2 tabs

The role of NK cells in HIV-1 protection: autologous, allogeneic or both?

Science.gov (United States)

Hens, Jef; Jennes, Wim; Kestens, Luc

2016-01-01

Natural killer (NK) cells specialize in killing virally infected- or tumor cells and are part of the innate immune system. The activational state of NK cells is determined by the balance of incoming activating and inhibitory signals mediated by receptor-ligand binding with the target cell. These receptor-ligand bonds mainly consist of the killer immunoglobulin-like receptors (KIR), which are expressed at the cell surface of NK cells, and their ligands: the highly variable human leukocyte antigen -class I molecules (HLA). Absence of an inhibitory receptor-ligand bond lowers the NK cell activation threshold, whereas an activating receptor-ligand bond stimulates the cell, potentially overcoming this threshold and triggering NK cell activation. NK cells influence the course of infection as well as the acquisition of HIV-1. Several lines of evidence relate the activating NK cell receptor KIR3DS1, in the presence or absence of its putative ligand HLA-Bw4, with slower disease progression as well as resistance to HIV-1 infection. Overall, resistance to HIV-1 infection predominantly correlates with activating KIR/HLA profiles, consisting of e.g. activating KIRs, group B haplotypes, or inhibitory KIRs in absence of their ligands. Such a conclusion is less evident for studies of HIV-1 disease progression, with studies reporting beneficial as well as detrimental effects of activating KIR/HLA genotypes. It is likely that KIR/HLA association studies are complicated by the complexity of the KIR and HLA loci and their mutual interactions, as well as by additional factors like route of HIV exposure, immune activation, presence of co-infections, and the effect of anti-HIV-1 antibodies. One newly discovered NK cell activation pathway associated with resistance to HIV-1 infection involves the presence of an iKIR/HLA mismatch between partners. The absence of such an iKIR/HLA bond renders donor-derived allogeneic HIV-1 infected cells vulnerable to NK cell responses during HIV-1

A comparative review of HLA associations with hepatitis B and C viral infections across global populations

Institute of Scientific and Technical Information of China (English)

Rashmi Singh; Rashmi Kaul; Anil Kaul; Khalid Khan

2007-01-01

Hepatitis B (HBV) and hepatitis C (HCV) viral infection or co-infection leads to risk of development of chronic infection, cirrhosis and hepatocellular carcinoma (HCC). Immigration and globalization have added to the challenges of public health concerns regarding chronic HBV and HCV infections worldwide. The aim of this study is to review existing global literature across ethnic populations on HBV and HCV related human leukocyte antigen (HLA) associations in relation to susceptibility, viral persistence and treatment. Extensive literature search was conducted to explore the HLA associations in HBV and HCV infections reported across global populations over the past decade to understand the knowledge status, weaknesses and strengths of this information in different ethnic populations. HLA DR13 is consistently associated with HBV clearance globally. HLADRB1*11/*12 alleles and DQB1*0301 are associated with HBV persistence but with HCV clearance worldwide. Consistent association of DRB1*03 and *07 is observed with HCV susceptibility and non-responsiveness to HBV vaccination across the population. HLA DR13 is protective for vertical HBV and HCV transmission in Chinese and Italian neonates, but different alleles are associated with their susceptibility in these populations. HLA class I molecule interactions with Killer cell immunoglobulin like receptors (KIR) of natural killer (NK) cells modulate HCV infection outcome via regulating immune regulatory cells and molecules. HLA associations with HBV vaccination, interferon therapy in HBV and HCV, and with extra hepatic manifestations of viral hepatitis are also discussed. Systematic studies in compliance with global regulatory standards are required to identify the HLA specific viral epitope, stage specific T cell populations interacting with different HLA alleles during disease progression and viral clearance ofchronic HBV or HCV infections among different ethnic populations. These studies would facilitate stage specific

De nonklassiske humant leukocyt-antigen (HLA)-vaevstyper--fra implantation til transplantation

DEFF Research Database (Denmark)

Hviid, Thomas Vauvert F

2006-01-01

), other functional HLA genes have been detected, the so-called non-classical HLA class Ib genes: HLA-E, -G and -F. They resemble the HLA class Ia antigens in many ways, but several major differences have been described. They are almost monomorphic and generally have a restricted pattern of expression. One...... has a role in implantation. A very strong expression of HLA-G is observed in the invasive trophoblast cells in the placenta. HLA-G may be involved in certain complications of pregnancy and the genetic predisposition to these. Finally, HLA-G expression has been associated with a reduced risk...

The impact of HLA matching on long-term transplant outcome after allogeneic hematopoietic stem cell transplantation for CLL: a retrospective study from the EBMT registry.

Science.gov (United States)

Michallet, M; Sobh, M; Milligan, D; Morisset, S; Niederwieser, D; Koza, V; Ruutu, T; Russell, N H; Verdonck, L; Dhedin, N; Vitek, A; Boogaerts, M; Vindelov, L; Finke, J; Dubois, V; van Biezen, A; Brand, R; de Witte, T; Dreger, P

2010-10-01

We analyzed 368 chronic lymphocytic leukemia patients who underwent allogeneic hematopoietic stem cell transplantation reported to the EBMT registry between 1995 and 2007. There were 198 human leukocyte antigen (HLA)-identical siblings; among unrelated transplants, 31 were well matched in high resolution ('well matched' unrelated donor, WMUD), and 139 were mismatched (MM), including 30 matched in low resolution; 266 patients (72%) received reduced-intensity conditioning and 102 (28%) received standard. According to the EBMT risk score, 11% were in scores 1-3, 23% in score 4, 40% in score 5, 22% in score 6 and 4% in score 7. There was no difference in overall survival (OS) at 5 years between HLA-identical siblings (55% (48-64)) and WMUD (59% (41-84)), P=0.82. In contrast, OS was significantly worse for MM (37% (29-48) P=0.005) due to a significant excess of transplant-related mortality. Also OS worsened significantly when EBMT risk score increased. HLA matching had no significant impact on relapse (siblings: 24% (21-27); WMUD: 35% (26-44), P=0.11 and MM: 21% (18-24), P=0.81); alemtuzumab T-cell depletion and stem cell source (peripheral blood) were associated with an increased risk. Our findings support the use of WMUD as equivalent alternative to HLA-matched sibling donors for allogeneic HSCT in CLL, and justify the application of EBMT risk score in this disease.

Trypanosoma brucei Co-opts NK Cells to Kill Splenic B2 B Cells.

Directory of Open Access Journals (Sweden)

Deborah Frenkel

2016-07-01

Full Text Available After infection with T. brucei AnTat 1.1, C57BL/6 mice lost splenic B2 B cells and lymphoid follicles, developed poor parasite-specific antibody responses, lost weight, became anemic and died with fulminating parasitemia within 35 days. In contrast, infected C57BL/6 mice lacking the cytotoxic granule pore-forming protein perforin (Prf1-/- retained splenic B2 B cells and lymphoid follicles, developed high-titer antibody responses against many trypanosome polypeptides, rapidly suppressed parasitemia and did not develop anemia or lose weight for at least 60 days. Several lines of evidence show that T. brucei infection-induced splenic B cell depletion results from natural killer (NK cell-mediated cytotoxicity: i B2 B cells were depleted from the spleens of infected intact, T cell deficient (TCR-/- and FcγRIIIa deficient (CD16-/- C57BL/6 mice excluding a requirement for T cells, NKT cell, or antibody-dependent cell-mediated cytotoxicity; ii administration of NK1.1 specific IgG2a (mAb PK136 but not irrelevant IgG2a (myeloma M9144 prevented infection-induced B cell depletion consistent with a requirement for NK cells; iii splenic NK cells but not T cells or NKT cells degranulated in infected C57BL/6 mice co-incident with B cell depletion evidenced by increased surface expression of CD107a; iv purified NK cells from naïve C57BL/6 mice killed purified splenic B cells from T. brucei infected but not uninfected mice in vitro indicating acquisition of an NK cell activating phenotype by the post-infection B cells; v adoptively transferred C57BL/6 NK cells prevented infection-induced B cell population growth in infected Prf1-/- mice consistent with in vivo B cell killing; vi degranulated NK cells in infected mice had altered gene and differentiation antigen expression and lost cytotoxic activity consistent with functional exhaustion, but increased in number as infection progressed indicating continued generation. We conclude that NK cells in T. brucei

Plasma-activated medium (PAM) kills human cancer-initiating cells.

Science.gov (United States)

Ikeda, Jun-Ichiro; Tanaka, Hiromasa; Ishikawa, Kenji; Sakakita, Hajime; Ikehara, Yuzuru; Hori, Masaru

2018-01-01

Medical non-thermal plasma (NTP) treatments for various types of cancers have been reported. Cells with tumorigenic potential (cancer-initiating cells; CICs) are few in number in many types of tumors. CICs efficiently eliminate anti-cancer chemicals and exhibit high-level aldehyde dehydrogenase (ALDH) activity. We previously examined the effects of direct irradiation via NTP on cancer cells; even though we targeted CICs expressing high levels of ALDH, such treatment affected both non-CICs and CICs. Recent studies have shown that plasma-activated medium (PAM) (culture medium irradiated by NTP) selectively induces apoptotic death of cancer but not normal cells. Therefore, we explored the anti-cancer effects of PAM on CICs among endometrioid carcinoma and gastric cancer cells. PAM reduced the viability of cells expressing both low and high levels of ALDH. Combined PAM/cisplatin appeared to kill cancer cells more efficiently than did PAM or cisplatin alone. In a mouse tumor xenograft model, PAM exerted an anti-cancer effect on CICs. Thus, our results suggest that PAM effectively kills both non-CICs and CICs, as does NTP. Therefore, PAM may be a useful new anti-cancer therapy, targeting various cancer cells including CICs. © 2017 Japanese Society of Pathology and John Wiley & Sons Australia, Ltd.

Mechanistic insights into selective killing of OXPHOS-dependent cancer cells by arctigenin.

Science.gov (United States)

Brecht, Karin; Riebel, Virginie; Couttet, Philippe; Paech, Franziska; Wolf, Armin; Chibout, Salah-Dine; Pognan, Francois; Krähenbühl, Stephan; Uteng, Marianne

2017-04-01

Arctigenin has previously been identified as a potential anti-tumor treatment for advanced pancreatic cancer. However, the mechanism of how arctigenin kills cancer cells is not fully understood. In the present work we studied the mechanism of toxicity by arctigenin in the human pancreatic cell line, Panc-1, with special emphasis on the mitochondria. A comparison of Panc-1 cells cultured in glucose versus galactose medium was applied, allowing assessments of effects in glycolytic versus oxidative phosphorylation (OXPHOS)-dependent Panc-1 cells. For control purposes, the mitochondrial toxic response to treatment with arctigenin was compared to the anti-cancer drug, sorafenib, which is a tyrosine kinase inhibitor known for mitochondrial toxic off-target effects (Will et al., 2008). In both Panc-1 OXPHOS-dependent and glycolytic cells, arctigenin dissipated the mitochondrial membrane potential, which was demonstrated to be due to inhibition of the mitochondrial complexes II and IV. However, arctigenin selectively killed only the OXPHOS-dependent Panc-1 cells. This selective killing of OXPHOS-dependent Panc-1 cells was accompanied by generation of ER stress, mitochondrial membrane permeabilization and caspase activation leading to apoptosis and aponecrosis. Copyright © 2016 Elsevier Ltd. All rights reserved.

Identification of novel HLA-A(*)0201-restricted CTL epitopes from Pokemon.

Science.gov (United States)

Yuan, Bangqing; Zhao, Lin; Xian, Ronghua; Zhao, Gang

2012-01-01

Pokemon is a member of the POK family of transcriptional repressors and aberrant overexpressed in various human cancers. Therefore, the related peptide epitopes derived from Pokemon is essential for the development of specific immunotherapy of malignant tumors. In this study, we predicted and identified HLA-A(*)0201-restricted cytotoxic T lymphocyte (CTL) epitopes derived from Pokemon with computer-based epitope prediction, peptide-binding assay and testing of the induced CTLs toward different kinds of carcinoma cells. The results demonstrated that effectors induced by peptides of Pokemon containing residues 32-40, 61-69, 87-95, and 319-327 could specifically secrete IFN-γ and lyse tumor cell lines of Pokemon-positive and HLA-A2-matched. The results suggest that Pokemon32, Pokemon61, Pokemon87, and Pokemon319 peptides are novel HLA-A(*)0201-restricted restricted CTL epitopes, and could be utilized in the cancer immunotherapy against a broad spectrum of tumors. Copyright © 2012 Elsevier Inc. All rights reserved.

Human Leukocyte Antigen (HLA) Class I Restricted Epitope Discovery in Yellow Fewer and Dengue Viruses: Importance of HLA Binding Strength

DEFF Research Database (Denmark)

Lund, Ole; Nascimento, Eduardo J. M.; Maciel, Milton, Jr

2011-01-01

Epitopes from all available full-length sequences of yellow fever virus (YFV) and dengue fever virus (DENV) restricted by Human Leukocyte Antigen class I (HLA-I) alleles covering 12 HLA-I supertypes were predicted using the NetCTL algorithm. A subset of 179 predicted YFV and 158 predicted DENV...... inoculated twice with the 17DD YFV vaccine strain. Three of the YFV A*02:01 restricted peptides activated T-cells from the infected mice in vitro. All three peptides that elicited responses had an HLA binding affinity of 2 nM or less. The results indicate the importance of the strength of HLA binding...

Template Driven Code Generator for HLA Middleware

NARCIS (Netherlands)

Jansen, R.E.J.; Prins, L.M.; Huiskamp, W.

2007-01-01

HLA is the accepted standard for simulation interoperability. However, the HLA services and the API that is provided for these services are relatively complex from the user point of view. Since the early days of HLA, federate developers have attempted to simplify their task by using middleware that

The role of HLA antibodies in allogeneic SCT: is the 'type-and-screen' strategy necessary not only for blood type but also for HLA?

Science.gov (United States)

Yoshihara, S; Taniguchi, K; Ogawa, H; Saji, H

2012-12-01

The role of HLA antibodies in SCT has drawn increasing attention because of the significantly increased number of patients who receive HLA-mismatched SCT, including cord blood transplantation, haploidentical SCT and unrelated SCT. Technical advancements in the methods of HLA Ab testing have realized rapid, accurate and objective identification, as well as quantification of specific HLA antibodies. Recent clinical studies have suggested that the presence of donor-specific HLA antibodies (DSA) in patients is associated with graft failure in HLA-mismatched SCT when the above-listed stem cell sources are used and results in different impacts. Of note, most of the 'HLA-matched' unrelated SCT actually involve HLA mismatches in HLA-DP and the presence of antibodies against this locus has been reported to be associated with graft failure. Thus, HLA Ab should be examined as a work-up for all patients who undergo SCT from 'alternative donors.' The simplest route for preventing HLA Ab-mediated graft failure in Ab-positive patients is to avoid donors who possess the target Ag of HLA antibodies. If SCT from such donors must be performed, treatment for DSA before SCT may improve the chances of successful donor engraftment.

Human leukocyte antigen (HLA class I restricted epitope discovery in yellow fewer and dengue viruses: importance of HLA binding strength.

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Ole Lund

Full Text Available Epitopes from all available full-length sequences of yellow fever virus (YFV and dengue fever virus (DENV restricted by Human Leukocyte Antigen class I (HLA-I alleles covering 12 HLA-I supertypes were predicted using the NetCTL algorithm. A subset of 179 predicted YFV and 158 predicted DENV epitopes were selected using the EpiSelect algorithm to allow for optimal coverage of viral strains. The selected predicted epitopes were synthesized and approximately 75% were found to bind the predicted restricting HLA molecule with an affinity, K(D, stronger than 500 nM. The immunogenicity of 25 HLA-A*02:01, 28 HLA-A*24:02 and 28 HLA-B*07:02 binding peptides was tested in three HLA-transgenic mice models and led to the identification of 17 HLA-A*02:01, 4 HLA-A*2402 and 4 HLA-B*07:02 immunogenic peptides. The immunogenic peptides bound HLA significantly stronger than the non-immunogenic peptides. All except one of the immunogenic peptides had K(D below 100 nM and the peptides with K(D below 5 nM were more likely to be immunogenic. In addition, all the immunogenic peptides that were identified as having a high functional avidity had K(D below 20 nM. A*02:01 transgenic mice were also inoculated twice with the 17DD YFV vaccine strain. Three of the YFV A*02:01 restricted peptides activated T-cells from the infected mice in vitro. All three peptides that elicited responses had an HLA binding affinity of 2 nM or less. The results indicate the importance of the strength of HLA binding in shaping the immune response.

Chimerism representing both paternal alleles detected by HLA typing before kidney transplantation

DEFF Research Database (Denmark)

Christiansen, Mette; Petersen, Mikkel Steen; Møller, Bjarne Kuno

2014-01-01

trisomy 6p or by chimerism. Flow cytometric analysis, employing antibodies specific for the two paternal HLA-A alleles, clearly showed two distinct populations of cells: 83% expressing HLA-A11 and 12% expressing HLA-A2, suggesting a paternal chimerism. We are studying these cell populations to possibly...... identify the mechanism behind this rather unusual paternally derived chimerism. This exceptional case illustrates that careful scrutiny of HLA-typing results may produce atypical conclusions. Clinically, the father is considered the best donor based on immunogenetics....

HAMLET kills tumor cells by apoptosis: structure, cellular mechanisms, and therapy.

Science.gov (United States)

Gustafsson, Lotta; Hallgren, Oskar; Mossberg, Ann-Kristin; Pettersson, Jenny; Fischer, Walter; Aronsson, Annika; Svanborg, Catharina

2005-05-01

New cancer treatments should aim to destroy tumor cells without disturbing normal tissue. HAMLET (human alpha-lactalbumin made lethal to tumor cells) offers a new molecular approach to solving this problem, because it induces apoptosis in tumor cells but leaves normal differentiated cells unaffected. After partial unfolding and binding to oleic acid, alpha-lactalbumin forms the HAMLET complex, which enters tumor cells and freezes their metabolic machinery. The cells proceed to fragment their DNA, and they disintegrate with apoptosis-like characteristics. HAMLET kills a wide range of malignant cells in vitro and maintains this activity in vivo in patients with skin papillomas. In addition, HAMLET has striking effects on human glioblastomas in a rat xenograft model. After convection-enhanced delivery, HAMLET diffuses throughout the brain, selectively killing tumor cells and controlling tumor progression without apparent tissue toxicity. HAMLET thus shows great promise as a new therapeutic with the advantage of selectivity for tumor cells and lack of toxicity.

Scientific projection paper for mutagenesis, transformation and cell killing

International Nuclear Information System (INIS)

Todd, P.

1980-01-01

Our knowledge about mutagenesis, transformation, and cell killing by ionizing radiation consists of large bodies of data, which are potentially useful in terms of application to human risk assessment and to the constructive use of radiation, as in cancer treatment. The three end-points discussed above are united by at least five significant concepts in radiation research strategy: (1) The inter-relationships among the important end-points, mutation, carcinogenesis, and cell killing. Research on one is meaningful only in the context of information about the other two. (2) The interaction of radiations with other agents in producing these end-points. (3) The mechanisms of action of other environmental mutagenic, carcinogenic, and cytotoxic agents. (4) The use of repair deficient human mutant cells. (5) The study of radiation damage mechanisms. There is no better way to extrapolate laboratory data to the clinical and public worlds than to understand the underlying biological mechanisms that produced the data

Universal cytotoxic activity of a HTLV-1 Tax-specific T cell clone from an HLA-A*24:02⁺ patient with adult T-cell leukemia against a variety of HTLV-I-infected T-cells.

Science.gov (United States)

Tanaka, Yukie; Yamazaki, Rie; Terasako-Saito, Kiriko; Nakasone, Hideki; Akahoshi, Yu; Nakano, Hirofumi; Ugai, Tomotaka; Wada, Hidenori; Yamasaki, Ryoko; Ishihara, Yuko; Kawamura, Koji; Sakamoto, Kana; Ashizawa, Masahiro; Sato, Miki; Kimura, Shun-ichi; Kikuchi, Misato; Kako, Shinichi; Kanda, Junya; Tanihara, Aki; Nishida, Junji; Kanda, Yoshinobu

2014-01-01

Adult T cell leukemia/lymphoma (ATL) is an aggressive mature T cell malignancy that is causally associated with human T cell lymphotropic virus type 1 (HTLV-1) infection. The HTLV-1 regulatory protein Tax aggressively accelerates the proliferation of host cells and is also an important target antigen for CD8(+) cytotoxic T cells (CTLs). We previously reported that several predominant HLA-A*24:02-restricted HTLV-1 Tax301-309-specific CTL clones commonly expressed a particular amino acid sequence motif (P-D-R) in complementarity-determining region 3 of T-cell receptor (TCR)-β chain among unrelated ATL patients who underwent allogeneic stem cell transplantation (allo-HSCT). Furthermore, a PDR-motif(+) CTL clone persistently existed in a long-term survivor as a central CTL clone with strong CTL activities after HSCT. Although a larger analysis of the relationship between PDR-motif(+) CTLs and the clinical course is required, the expression of PDR-motif(+) TCR on CD8(+) T cells may play a critical role in the management of anti-HTLV-1 activities for HLA-A24:02(+) ATL patients. Therefore, in this study, we prepared an HTLV-1 Tax301-309 peptide-specific CTL clone (HT-9) expressing PDR-motif(+) TCR isolated from a long-term survivor after HSCT, and evaluated its CTL activity against a variety of HTLV-1-infected T-cells from HLA-A*24:02(+) ATL patients. Before the assay of CTL function, we confirmed that HT-9 expressed less-differentiated effector-memory phenotypes (CD45RA(-)CCR7(-)CD27(+)CD28(+/-)CD57(+/-)) and T-cell exhaustion marker PD-1(+). In assays of CTL function, HT-9 recognized HTLV-1 Tax in an HLA-restricted fashion and demonstrated strong CTL activities against a variety of HTLV-1-infected T-cells from HLA-A*24:02(+) ATL patients regardless of whether the sources were autologous or allogeneic, but not normal cells. These data indicate that PDR-motif(+) TCR could be an important TCR candidate for TCR-gene immunotherapy for HLA-A24:02(+) ATL patients, provided

Spontaneous control of HIV-1 viremia in a subject with protective HLA-B plus HLA-C alleles and HLA-C associated single nucleotide polymorphisms.

Science.gov (United States)

Moroni, Marco; Ghezzi, Silvia; Baroli, Paolo; Heltai, Silvia; De Battista, Davide; Pensieroso, Simone; Cavarelli, Mariangela; Dispinseri, Stefania; Vanni, Irene; Pastori, Claudia; Zerbi, Pietro; Tosoni, Antonella; Vicenzi, Elisa; Nebuloni, Manuela; Wong, Kim; Zhao, Hong; McHugh, Sarah; Poli, Guido; Lopalco, Lucia; Scarlatti, Gabriella; Biassoni, Roberto; Mullins, James I; Malnati, Mauro S; Alfano, Massimo

2014-12-05

Understanding the mechanisms by which some individuals are able to naturally control HIV-1 infection is an important goal of AIDS research. We here describe the case of an HIV-1(+) woman, CASE1, who has spontaneously controlled her viremia for the last 14 of her 20 years of infection. CASE1 has been clinically monitored since 1993. Detailed immunological, virological and histological analyses were performed on samples obtained between 2009 and 2011. As for other Elite Controllers, CASE1 is characterized by low to undetectable levels of plasma HIV-1 RNA, peripheral blood mononuclear cell (PBMC) associated HIV-1 DNA and reduced in vitro susceptibility of target cells to HIV-1 infection. Furthermore, a slow rate of virus evolution was demonstrated in spite the lack of assumption of any antiretroviral agent. CASE1 failed to transmit HIV-1 to either her sexual male partner or to her child born by vaginal delivery. Normal values and ratios of T and B cells were observed, along with normal histology of the intestinal mucosa. Attempts to isolate HIV-1 from her PBMC and gut-derived cells were unsuccessful, despite expression of normal cell surface levels of CD4, CCRC5 and CXCR4. CASE1 did not produce detectable anti-HIV neutralizing antibodies in her serum or genital mucosal fluid although she displayed potent T cell responses against HIV-1 Gag and Nef. CASE1 also possessed multiple genetic polymorphisms, including HLA alleles (B*14, B*57, C*06 and C*08.02) and HLA-C single nucleotide polymorphisms (SNPs, rs9264942 C/C and rs67384697 del/del), that have been previously individually associated with spontaneous control of plasma viremia, maintenance of high CD4(+) T cell counts and delayed disease progression. CASE1 has controlled her HIV-1 viremia below the limit of detection in the absence of antiretroviral therapy for more than 14 years and has not shown any sign of immunologic deterioration or disease progression. Co-expression of multiple protective HLA alleles, HLA

HLA typing: Conventional techniques v. next-generation sequencing ...

African Journals Online (AJOL)

Background. The large number of population-specific polymorphisms present in the HLA complex in the South African (SA) population reduces the probability of finding an adequate HLA-matched donor for individuals in need of an unrelated haematopoietic stem cell transplantation (HSCT). Next-generation sequencing ...

DIFFERENTIAL IMPACT OF HLA-A, HLA-B AND HLA-DR COMPATIBILITY ON THE RENAL ALLOGRAFT SURVIVAL

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V. Y. Abramov

2012-01-01

Full Text Available We studied the long-term results of 532 deceased donor kidney transplantations to investigate the impact of HLA match on the survival of renal allograft. All transplants were performed in our center in 1996–2009 and moni- tored prospectively for 1–14 years. We found, the survival of 58 kidneys grafted with 0–2 mismatch for HLA- ABDR to be significantly better (Plogrank = 0,016 than the survival of the kidneys grafted with 3–6 HLA-ABDR mismatch. The full compatibility for HLA-A (n = 75 did not influence the long-term survival (Plogrank = 0,48. The absence of HLA-DR mismatch had a beneficial effect for survival of 68 kidneys (Plogrank = 0,07. Eighteen cases with the full HLA-B compatibility between graft and recipient demonstrated excellent long-term survival (Plogrank = 0,007. HLA-B compatibility influenced significantly (P = 0,042 the survival of transplanted kidney in the Cox regression model adjusted for donor and recipient age, panel-reactive antibody level, re-transplant, and immunosuppression protocol. The data obtained support the conclusion, that HLA compatibility should be one of the criteria of deceased donor kidney allocation. 

PD1/PD1L pathway, HLA-G and T regulatory cells as new markers of immunosuppression in cancers

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Paulina Własiuk

2016-10-01

Full Text Available The appropriate function of the immune system depends on the effective regulation of the immune response on multiple levels. The key element of an effective immune response to antigenic stimulation is maintaining a homeostasis between activation and inhibitory function of immunocompetent cells and molecules. In pathological conditions such as chronic infections, autoimmune diseases or cancer there are significant alterations, and prevalence of signals of one type over another. Main markers of these dysfunctions are altered expressions of molecules, such as programmed death-1 (PD-1, Human Leukocyte Antigen G (HLA-G, or changed percentages of T regulatory cells (Treg. These indicators of immune system dysfunction may contribute to disease progression, but also could represent good targets for treatment. Interestingly, in recent years there are many new, interesting reports which showed that the role of PD-1, HLA-G or Treg is ambiguous and not always their higher expression or frequency lead to the progression of disease. Recent studies have shown that Treg can suppress bacteria-driven inflammation which promotes carcinogenesis and thus protect the host from cancer development. Moreover, proliferation of hematological tumor cells expressing ILT-2 receptor can be inhibited by HLA-G, in contrast to solid tumors where HLA-G favors tumor escape. In this paper we present characteristics of expressions of PD-1 and its ligands, HLA-G, and frequency of Treg cells in a variety of physiological and pathological conditions associated with chronic infections, autoimmune diseases and cancer. The understanding of the complex interactions between the functional elements of immune system is essential for a detailed characteristics of the mechanisms leading to the development of diseases and identification of more effective targeted therapies.

Role of nitric oxide in Salmonella typhimurium-mediated cancer cell killing

International Nuclear Information System (INIS)

Barak, Yoram; Schreiber, Frank; Thorne, Steve H; Contag, Christopher H; DeBeer, Dirk; Matin, A

2010-01-01

Bacterial targeting of tumours is an important anti-cancer strategy. We previously showed that strain SL7838 of Salmonella typhimurium targets and kills cancer cells. Whether NO generation by the bacteria has a role in SL7838 lethality to cancer cells is explored. This bacterium has the mechanism for generating NO, but also for decomposing it. Mechanism underlying Salmonella typhimurium tumour therapy was investigated through in vitro and in vivo studies. NO measurements were conducted either by chemical assays (in vitro) or using Biosensors (in vivo). Cancer cells cytotoxic assay were done by using MTS. Bacterial cell survival and tumour burden were determined using molecular imaging techniques. SL7838 generated nitric oxide (NO) in anaerobic cell suspensions, inside infected cancer cells in vitro and in implanted 4T1 tumours in live mice, the last, as measured using microsensors. Thus, under these conditions, the NO generating pathway is more active than the decomposition pathway. The latter was eliminated, in strain SL7842, by the deletion of hmp- and norV genes, making SL7842 more proficient at generating NO than SL7838. SL7842 killed cancer cells more effectively than SL7838 in vitro, and this was dependent on nitrate availability. This strain was also ca. 100% more effective in treating implanted 4T1 mouse tumours than SL7838. NO generation capability is important in the killing of cancer cells by Salmonella strains

Killing multiple myeloma cells with the small molecule 3-bromopyruvate: implications for therapy.

Science.gov (United States)

Majkowska-Skrobek, Grażyna; Augustyniak, Daria; Lis, Paweł; Bartkowiak, Anna; Gonchar, Mykhailo; Ko, Young H; Pedersen, Peter L; Goffeau, Andre; Ułaszewski, Stanisław

2014-07-01

The small molecule 3-bromopyruvate (3-BP), which has emerged recently as the first member of a new class of potent anticancer agents, was tested for its capacity to kill multiple myeloma (MM) cancer cells. Human MM cells (RPMI 8226) begin to lose viability significantly within 8 h of incubation in the presence of 3-BP. The Km (0.3 mmol/l) for intracellular accumulation of 3-BP in MM cells is 24 times lower than that in control cells (7.2 mmol/l). Therefore, the uptake of 3-BP by MM cells is significantly higher than that by peripheral blood mononuclear cells. Further, the IC50 values for human MM cells and control peripheral blood mononuclear cells are 24 and 58 µmol/l, respectively. Therefore, specificity and selectivity of 3-BP toward MM cancer cells are evident on the basis of the above. In MM cells the transcription levels of the gene encoding the monocarboxylate transporter MCT1 is significantly amplified compared with control cells. The level of intracellular ATP in MM cells decreases by over 90% within 1 h after addition of 100 µmol/l 3-BP. The cytotoxicity of 3-BP, exemplified by a marked decrease in viability of MM cells, is potentiated by the inhibitor of glutathione synthesis buthionine sulfoximine. In addition, the lack of mutagenicity and its superior capacity relative to Glivec to kill MM cancer cells are presented in this study.

Can Non-HLA Single Nucleotide Polymorphisms Help Stratify Risk in TrialNet Relatives at Risk for Type 1 Diabetes?

Science.gov (United States)

Steck, Andrea K; Xu, Ping; Geyer, Susan; Redondo, Maria J; Antinozzi, Peter; Wentworth, John M; Sosenko, Jay; Onengut-Gumuscu, Suna; Chen, Wei-Min; Rich, Stephen S; Pugliese, Alberto

2017-08-01

Genome-wide association studies identified >50 type 1 diabetes (T1D) associated non-human leukocyte antigens (non-HLA) loci. The purpose of this study was to assess the contribution of non-HLA single nucleotide polymorphisms (SNPs) to risk of disease progression. The TrialNet Pathway to Prevention Study follows relatives of T1D patients for development of autoantibodies (Abs) and T1D. Using the Immunochip, we analyzed 53 diabetes-associated, non-HLA SNPs in 1016 Ab-positive, at-risk non-Hispanic white relatives. Effect of SNPs on the development of multiple Abs and T1D. Cox proportional analyses included all substantial non-HLA SNPs, HLA genotypes, relationship to proband, sex, age at initial screening, initial Ab type, and number. Factors involved in progression from single to multiple Abs included age at screening, relationship to proband, HLA genotypes, and rs3087243 (cytotoxic T lymphocyte antigen-4). Significant factors for diabetes progression included age at screening, Ab number, HLA genotypes, rs6476839 [GLIS family zinc finger 3 (GLIS3)], and rs3184504 [SH2B adaptor protein 3 (SH2B3)]. When glucose area under the curve (AUC) was included, factors involved in disease progression included glucose AUC, age at screening, Ab number, relationship to proband, HLA genotypes, rs6476839 (GLIS3), and rs7221109 (CCR7). In stratified analyses by age, glucose AUC, age at screening, sibling, HLA genotypes, rs6476839 (GLIS3), and rs4900384 (C14orf64) were significantly associated with progression to diabetes in participants <12 years old, whereas glucose AUC, sibling, rs3184504 (SH2B3), and rs4900384 (C14orf64) were significant in those ≥12. In conclusion, we identified five non-HLA SNPs associated with increased risk of progression from Ab positivity to disease that may improve risk stratification for prevention trials. Copyright © 2017 by the Endocrine Society

Epigenetic changes within the promoter region of the HLA-G gene in ovarian tumors

Directory of Open Access Journals (Sweden)

Matyunina Lilya V

2008-05-01

Full Text Available Abstract Background Previous findings have suggested that epigenetic-mediated HLA-G expression in tumor cells may be associated with resistance to host immunosurveillance. To explore the potential role of DNA methylation on HLA-G expression in ovarian cancer, we correlated differences in HLA-G expression with methylation changes within the HLA-G regulatory region in an ovarian cancer cell line treated with 5-aza-deoxycytidine (5-aza-dC and in malignant and benign ovarian tumor samples and ovarian surface epithelial cells (OSE isolated from patients with normal ovaries. Results A region containing an intact hypoxia response element (HRE remained completely methylated in the cell line after treatment with 5-aza-dC and was completely methylated in all of the ovarian tumor (malignant and benign samples examined, but only variably methylated in normal OSE samples. HLA-G expression was significantly increased in the 5-aza-dC treated cell line but no significant difference was detected between the tumor and OSE samples examined. Conclusion Since HRE is the binding site of a known repressor of HLA-G expression (HIF-1, we hypothesize that methylation of the region surrounding the HRE may help maintain the potential for expression of HLA-G in ovarian tumors. The fact that no correlation exists between methylation and HLA-G gene expression between ovarian tumor samples and OSE, suggests that changes in methylation may be necessary but not sufficient for HLA-G expression in ovarian cancer.

Selective changes in expression of HLA class I polymorphic determinants in human solid tumors

International Nuclear Information System (INIS)

Natali, P.G.; Nicotra, M.R.; Bigotti, A.; Venturo, I.; Giacomini, P.; Marcenaro, L.; Russo, C.

1989-01-01

Analysis of surgical biopsies with monoclonal antibodies (mAbs) to framework determinants of major histocompatibility complex class I antigens has shown that malignant transformation is frequently associated with a marked loss of these cell surface molecules. The present study sought to determine whether more selective losses of major histocompatibility complex class I expression occur. Multiple specimens from 13 different types of primary and metastatic tumors were tested utilizing mAb BB7.2, which recognizes a polymorphic HLA-A2 epitope. In each case, expression of HLA-A,B,C molecules was determined by testing with mAb W6/32 directed to a framework HLA class I determinant. The authors have found that in HLA-A2-positive patients, HLA-A2 products are not detectable or are reduced in their expression in 70-80% of endometrial, colorectal, mammary, and renal tumors; in 40-60% of soft-tissue, skin, ovary, urinary bladder, prostate, and stomach tumors; and in 25-30% of melanomas and lung carcinomas tested. All tumors expressed the framework HLA-A,B.C determinant. The HLA-A2 epitope recognized by mAb BB7.2 is located in a portion of the HLA-A2 molecule postulated to react with the T-cell receptor. The selective loss of an HLA class I polymorphic epitope shown in this study may explain the mechanism by which tumor cells escape both T-cell recognition and natural killer cell surveillance

HLA Class II Defects in Burkitt Lymphoma: Bryostatin-1-Induced 17 kDa Protein Restores CD4+ T-Cell Recognition

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Azim Hossain

2011-01-01

Full Text Available While the defects in HLA class I-mediated Ag presentation by Burkitt lymphoma (BL have been well documented, CD4+ T-cells are also poorly stimulated by HLA class II Ag presentation, and the reasons underlying this defect(s have not yet been fully resolved. Here, we show that BL cells are deficient in their ability to optimally stimulate CD4+ T cells via the HLA class II pathway. The observed defect was not associated with low levels of BL-expressed costimulatory molecules, as addition of external co-stimulation failed to result in BL-mediated CD4+ T-cell activation. We further demonstrate that BL cells express the components of the class II pathway, and the defect was not caused by faulty Ag/class II interaction, because antigenic peptides bound with measurable affinity to BL-associated class II molecules. Treatment of BL with broystatin-1, a potent modulator of protein kinase C, led to significant improvement of functional class II Ag presentation in BL. The restoration of immune recognition appeared to be linked with an increased expression of a 17 kDa peptidylprolyl-like protein. These results demonstrate the presence of a specific defect in HLA class II-mediated Ag presentation in BL and reveal that treatment with bryostatin-1 could lead to enhanced immunogenicity.

Multiple factors and processes involved in host cell killing by bacteriophage Mu: characterization and mapping.

Science.gov (United States)

Waggoner, B T; Marrs, C F; Howe, M M; Pato, M L

1984-07-15

The regions of bacteriophage Mu involved in host cell killing were determined by infection of a lambda-immune host with 12 lambda pMu-transducing phages carrying different amounts of Mu DNA beginning at the left end. Infecting lambda pMu phages containing 5.0 (+/- 0.2) kb or less of the left end of Mu DNA did not kill the lambda-immune host, whereas lambda pMu containing 5.1 kb did kill, thus locating the right end of the kil gene between approximately 5.0 and 5.1 kb. For the Kil+ phages the extent of killing increased as the multiplicity of infection (m.o.i.) increased. In addition, killing was also affected by the presence of at least two other regions of Mu DNA: one, located between 5.1 and 5.8 kb, decreased the extent of killing; the other, located between 6.3 and 7.9 kb, greatly increased host cell killing. Killing was also assayed after lambda pMu infection of a lambda-immune host carrying a mini-Mu deleted for most of the B gene and the middle region of Mu DNA. Complementation of mini-Mu replication by infecting B+ lambda pMu phages resulted in killing of the lambda-immune, mini-Mu-containing host, regardless of the presence or absence of the Mu kil gene. The extent of host cell killing increased as the m.o.i. of the infecting lambda pMu increased, and was further enhanced by both the presence of the kil gene and the region located between 6.3 and 7.9 kb. These distinct processes of kil-mediated killing in the absence of replication and non-kil-mediated killing in the presence of replication were also observed after induction of replication-deficient and kil mutant prophages, respectively.

Utility of HLA Antibody Testing in Kidney Transplantation

Science.gov (United States)

Konvalinka, Ana

2015-01-01

HLA antigens are polymorphic proteins expressed on donor kidney allograft endothelium and are critical targets for recipient immune recognition. HLA antibodies are risk factors for acute and chronic rejection and allograft loss. Solid-phase immunoassays for HLA antibody detection represent a major advance in sensitivity and specificity over cell-based methods and are widely used in organ allocation and pretransplant risk assessment. Post-transplant, development of de novo donor–specific HLA antibodies and/or increase in donor-specific antibodies from pretransplant levels are associated with adverse outcomes. Although single antigen bead assays have allowed sensitive detection of recipient HLA antibodies and their specificities, a number of interpretive considerations must be appreciated to understand test results in clinical and research contexts. This review, which is especially relevant for clinicians caring for transplant patients, discusses the technical aspects of single antigen bead assays, emphasizes their quantitative limitations, and explores the utility of HLA antibody testing in identifying and managing important pre- and post-transplant clinical outcomes. PMID:25804279

Flow cytometric analysis of cell killing by the jumper ant venom peptide pilosulin 1.

Science.gov (United States)

King, M A; Wu, Q X; Donovan, G R; Baldo, B A

1998-08-01

Pilosulin 1 is a synthetic 56-amino acid residue polypeptide that corresponds to the largest allergenic polypeptide found in the venom of the jumper ant Myrmecia pilosula. Initial experiments showed that pilosulin 1 lysed erythrocytes and killed proliferating B cells. Herein, we describe how flow cytometry was used to investigate the cytotoxicity of the peptide for human white blood cells. Cells were labeled with fluorochrome-conjugated antibodies, incubated with the peptide and 7-aminoactinomycin D (7-AAD), and then analyzed. The effects of varying the peptide concentration, serum concentration, incubation time, and incubation temperature were measured, and the cytotoxicity of pilosulin 1 was compared with that of the bee venom peptide melittin. The antibodies and the 7-AAD enabled the identification of cell subpopulations and dead cells, respectively. It was possible, using the appropriate mix of antibodies and four-color analysis, to monitor the killing of three or more cell subpopulations simultaneously. We found that 1) pilosulin 1 killed cells within minutes, with kinetics similar to those of melittin; 2) pilosulin 1 was a slightly more potent cytotoxic agent than melittin; 3) both pilosulin 1 and melittin were more potent against mononuclear leukocytes than against granulocytes; and 4) serum inhibited killing by either peptide.

Influence of Human Leukocyte Antigen (HLA) Alleles and Killer Cell Immunoglobulin-Like Receptors (KIR) Types on Heparin-Induced Thrombocytopenia (HIT).

Science.gov (United States)

Karnes, Jason H; Shaffer, Christian M; Cronin, Robert; Bastarache, Lisa; Gaudieri, Silvana; James, Ian; Pavlos, Rebecca; Steiner, Heidi E; Mosley, Jonathan D; Mallal, Simon; Denny, Joshua C; Phillips, Elizabeth J; Roden, Dan M

2017-09-01

Heparin-induced thrombocytopenia (HIT) is an unpredictable, life-threatening, immune-mediated reaction to heparin. Variation in human leukocyte antigen (HLA) genes is now used to prevent immune-mediated adverse drug reactions. Combinations of HLA alleles and killer cell immunoglobulin-like receptors (KIR) are associated with multiple autoimmune diseases and infections. The objective of this study is to evaluate the association of HLA alleles and KIR types, alone or in the presence of different HLA ligands, with HIT. HIT cases and heparin-exposed controls were identified in BioVU, an electronic health record coupled to a DNA biobank. HLA sequencing and KIR type imputation using Illumina OMNI-Quad data were performed. Odds ratios for HLA alleles and KIR types and HLA*KIR interactions using conditional logistic regressions were determined in the overall population and by race/ethnicity. Analysis was restricted to KIR types and HLA alleles with a frequency greater than 0.01. The p values for HLA and KIR association were corrected by using a false discovery rate qHIT cases and 350 matched controls were identified. No statistical differences in baseline characteristics were observed between cases and controls. The HLA-DRB3*01:01 allele was significantly associated with HIT in the overall population (odds ratio 2.81 [1.57-5.02], p=2.1×10 -4 , q=0.02) and in individuals with European ancestry, independent of other alleles. No KIR types were associated with HIT, although a significant interaction was observed between KIR2DS5 and the HLA-C1 KIR binding group (p=0.03). The HLA-DRB3*01:01 allele was identified as a potential risk factor for HIT. This class II HLA gene and allele represent biologically plausible candidates for influencing HIT pathogenesis. We found limited evidence of the role of KIR types in HIT pathogenesis. Replication and further study of the HLA-DRB3*01:01 association is necessary. © 2017 Pharmacotherapy Publications, Inc.

Human amnion epithelial cells expressing HLA-G as novel cell-based treatment for liver disease.

Science.gov (United States)

Strom, Stephen C; Gramignoli, Roberto

2016-09-01

Despite routine liver transplantation and supporting medical therapies, thousands of patients currently wait for an organ and there is an unmet need for more refined and widely available regenerative strategies to treat liver diseases. Cell transplants attempt to maximize the potential for repair and/or regeneration in liver and other organs. Over 40years of laboratory pre-clinical research and 25years of clinical procedures have shown that certain liver diseases can be treated by the infusion of isolated cells (hepatocyte transplant). However, like organ transplants, hepatocyte transplant suffers from a paucity of tissues useful for cell production. Alternative sources have been investigated, yet with limited success. The tumorigenic potential of pluripotent stem cells together with their primitive level of hepatic differentiation, have limited the use of stem cell populations. Stem cell sources from human placenta, and the amnion tissue in particular are receiving renewed interest in the field of regenerative medicine. Unlike pluripotent stem cells, human amnion epithelial (AE) cells are easily available without ethical or religious concerns; they do not express telomerase and are not immortal or tumorigenic when transplanted. In addition, AE cells have been reported to express genes normally expressed in mature liver, when transplanted into the liver. Moreover, because of the possibility of an immune-privileged status related to their expression of HLA-G, it might be possible to transplant human AE cells without immunosuppression of the recipient. Copyright © 2016. Published by Elsevier Inc.

HLA-A, HLA-B, and HLA-DRB1 Allele and Haplotype Frequencies in Renal Transplant Candidates in a Population in Southern Brazil.

Science.gov (United States)

Saito, Patrícia Keiko; Yamakawa, Roger Haruki; Noguti, Erika Noda; Bedendo, Gustavo Borelli; Júnior, Waldir Veríssimo da Silva; Yamada, Sérgio Seiji; Borelli, Sueli Donizete

2016-05-01

Very few studies have examined the diversity of human leukocyte antigens (HLA) in the Brazilian renal transplant candidates. The frequencies of the HLA-A, HLA-B, and HLA-DRB1 alleles, haplotypes and phenotypes were studied in 522 patients with chronic renal failure, renal transplant candidates, registered at the Transplant Centers in north/northwestern Paraná State, southern Brazil. Patients were classified according to the ethnic group (319 whites [Caucasians], 134 mestizos [mixed race descendants of Europeans, Africans, and Amerindians; browns or "pardos"] and 69 blacks). The HLA typing was performed by the polymerase chain reaction sequence-specific oligonucleotide method (PCR-SSO), combined with Luminex technology. In the analysis of the total samples, 20 HLA-A, 32 HLA-B, and 13 HLA-DRB1 allele groups were identified. The most frequent allele groups for each HLA locus were HLA-A*02 (25.4%), HLA-B*44 (10.9%), and HLA-DRB1*13 (13.9%). The most frequent haplotypes were HLA-A*01-B*08-DRB1*03 (2.3%), A*02-B*44-DRB1*07 (1.2%), and A*03-B*07-DRB1*11 (1.0%). Significant differences (P < 0.05) were observed in the HLA-A*68, B*08, and B*58 allele frequencies among ethnic groups. This study provides the first data on the HLA-A, HLA-B, and HLA-DRB1 allele, phenotype and haplotype frequencies of renal transplant candidates in a population in southern Brazil. © 2015 Wiley Periodicals, Inc.

The Mycobacterium tuberculosis phagosome is a HLA-I processing competent organelle.

Directory of Open Access Journals (Sweden)

Jeff E Grotzke

2009-04-01

Full Text Available Mycobacterium tuberculosis (Mtb resides in a long-lived phagosomal compartment that resists maturation. The manner by which Mtb antigens are processed and presented on MHC Class I molecules is poorly understood. Using human dendritic cells and IFN-gamma release by CD8(+ T cell clones, we examined the processing and presentation pathway for two Mtb-derived antigens, each presented by a distinct HLA-I allele (HLA-Ia versus HLA-Ib. Presentation of both antigens is blocked by the retrotranslocation inhibitor exotoxin A. Inhibitor studies demonstrate that, after reaching the cytosol, both antigens require proteasomal degradation and TAP transport, but differ in the requirement for ER-golgi egress and new protein synthesis. Specifically, presentation by HLA-B8 but not HLA-E requires newly synthesized HLA-I and transport through the ER-golgi. Phenotypic analysis of the Mtb phagosome by flow organellometry revealed the presence of Class I and loading accessory molecules, including TAP and PDI. Furthermore, loaded HLA-I:peptide complexes are present within the Mtb phagosome, with a pronounced bias towards HLA-E:peptide complexes. In addition, protein analysis also reveals that HLA-E is enriched within the Mtb phagosome compared to HLA-A2. Together, these data suggest that the phagosome, through acquisition of ER-localized machinery and as a site of HLA-I loading, plays a vital role in the presentation of Mtb-derived antigens, similar to that described for presentation of latex bead-associated antigens. This is, to our knowledge, the first description of this presentation pathway for an intracellular pathogen. Moreover, these data suggest that HLA-E may play a unique role in the presentation of phagosomal antigens.

An Fc engineering approach that modulates antibody-dependent cytokine release without altering cell-killing functions.

Science.gov (United States)

Kinder, Michelle; Greenplate, Allison R; Strohl, William R; Jordan, Robert E; Brezski, Randall J

2015-01-01

Cytotoxic therapeutic monoclonal antibodies (mAbs) often mediate target cell-killing by eliciting immune effector functions via Fc region interactions with cellular and humoral components of the immune system. Key functions include antibody-dependent cell-mediated cytotoxicity (ADCC), antibody-dependent cellular phagocytosis (ADCP), and complement-dependent cytotoxicity (CDC). However, there has been increased appreciation that along with cell-killing functions, the induction of antibody-dependent cytokine release (ADCR) can also influence disease microenvironments and therapeutic outcomes. Historically, most Fc engineering approaches have been aimed toward modulating ADCC, ADCP, or CDC. In the present study, we describe an Fc engineering approach that, while not resulting in impaired ADCC or ADCP, profoundly affects ADCR. As such, when peripheral blood mononuclear cells are used as effector cells against mAb-opsonized tumor cells, the described mAb variants elicit a similar profile and quantity of cytokines as IgG1. In contrast, although the variants elicit similar levels of tumor cell-killing as IgG1 with macrophage effector cells, the variants do not elicit macrophage-mediated ADCR against mAb-opsonized tumor cells. This study demonstrates that Fc engineering approaches can be employed to uncouple macrophage-mediated phagocytic and subsequent cell-killing functions from cytokine release.

Haematopoietic transplants combining a single unrelated cord blood unit and mobilized haematopoietic stem cells from an adult HLA-mismatched third party donor. Comparable results to transplants from HLA-identical related donors in adults with acute leukaemia and myelodysplastic syndromes.

Science.gov (United States)

Sebrango, Ana; Vicuña, Isabel; de Laiglesia, Almudena; Millán, Isabel; Bautista, Guiomar; Martín-Donaire, Trinidad; Regidor, Carmen; Cabrera, Rafael; Fernandez, Manuel N

2010-06-01

We describe results of the strategy, developed by our group, of co-infusion of mobilized haematopoietic stem cells as a support for single-unit unrelated cord blood transplant (dual CB/TPD-MHSC transplants) for treatment of haematological malignancies in adults, and a comparative analysis of results obtained using this strategy and transplants performed with mobilized haematopoietic stem cells from related HLA-identical donors (RTD) for treatment of adults with acute leukaemia and myelodysplastic syndromes. Our data show that the dual CB/TPD-MHSC transplant strategy results in periods of post-transplant neutropenia, final rates of full donor chimerism and transplant-related mortality rates comparable to those of the RTD. Final survival outcomes are comparable in adults transplanted because of acute leukaemia, with different incidences of the complications that most influence these: a higher incidence of infections related to late recovery of protective immunity dependent on T cell functions, and a lower incidence of serious acute graft-versus-host disease and relapses. Recent advances in cord blood transplant techniques allow allogeneic haematopoietic stem cell transplantation (HSCT) to be a viable option for almost every patient who may benefit from this therapeutic approach. Development of innovative strategies to improve the post-transplant recovery of T cells function is currently the main challenge to further improving the possibilities of unrelated cord blood transplantation. Copyright © 2010 Elsevier Ltd. All rights reserved.

Genetic studies of the HLA-D region by the primed lymphocyte test

International Nuclear Information System (INIS)

DeWolf, W.C.; Carroll, P.G.; Yunis, E.J.

1978-01-01

The control and influence of the stimulating DRw antigens on primed lymphocyte typing (PLT) response was studied by using a discriminatory PLT assay with a low responder: stimulator ratio. Positive restimulation was established at 90.3% RR, based on a statistical evaluation of a composite or %RR values from 13 separate intrafamily PLTs performed in this laboratory. Two intrafamily PLT cells were then made against specificities HLA-DRwl and HLA-DRw3 and restimulated with a panel of unrelated individuals. The results show a very high correlation (p < 0.001) between the HLA-DRw antigen specificity of those unrelated panel cells that stimulated in PLT and the HLA-DRw target specificity, which shows that PLT reactivity is strongly influenced by HLA-DRw

Gestational diabetes mellitus is associated with TCF7L2 gene polymorphisms independent of HLA-DQB1*0602 genotypes and islet cell autoantibodies

Science.gov (United States)

Papadopoulou, A.; Lynch, K. F.; Shaat, N.; Håkansson, R.; Ivarsson, S. A.; Berntorp, K.; Agardh, C. D.; Lernmark, Å

2011-01-01

Aims To test whether the TCF7L2 gene was associated with gestational diabetes, whether the association between TCF7L2 and gestational diabetes was independent of HLA-DQB1*0602 and islet cell autoantibodies, as well as maternal age, number of pregnancies, family history of diabetes and the HLA-DQB1 genotypes, and to test whether the distribution of HLA-DQB1 alleles was affected by country of birth. Methods We genotyped the rs7903146, rs12255372 and rs7901695 single nucleotide polymorphisms of the TCF7L2 gene in 826 mothers with gestational diabetes and in 1185 healthy control subjects in the Diabetes Prediction in Skåne Study. The mothers were also typed for HLA-DQB1 genotypes and tested for islet cell autoantibodies against GAD65, insulinoma-associated antigen-2 and insulin. Results The heterozygous genotypes CT, GT and TC of the rs7903146 (T is risk for Type 2 diabetes), rs12255372 (T is risk for Type 2 diabetes) and rs7901695 (C is risk for Type 2 diabetes), respectively, as well as the homozygous genotypes TT, TT and CC of the rs7903146, rs12255372 and rs7901695, respectively, were strongly associated with gestational diabetes (P gestational diabetes in mothers born in Sweden (P = 0.010). Conclusions The TCF7L2 was associated with susceptibility for gestational diabetes independently of the presence of HLA-DQB1*0602 and islet cell autoantibodies and other factors such as maternal age, number of pregnancies, family history of diabetes and other HLA-DQ genotypes. The HLA-DQB1*0602 was negatively associated with gestational diabetes in mothers born in Sweden. PMID:21672010

Defining the HLA class I-associated viral antigen repertoire from HIV-1-infected human cells

DEFF Research Database (Denmark)

Ternette, Nicola; Yang, Hongbing; Partridge, Thomas

2016-01-01

Recognition and eradication of infected cells by cytotoxic T lymphocytes is a key defense mechanism against intracellular pathogens. High-throughput definition of HLA class I-associated immunopeptidomes by mass spectrometry is an increasingly important analytical tool to advance our understanding...

MHC class II super-enhancer increases surface expression of HLA-DR and HLA-DQ and affects cytokine production in autoimmune vitiligo.

Science.gov (United States)

Cavalli, Giulio; Hayashi, Masahiro; Jin, Ying; Yorgov, Daniel; Santorico, Stephanie A; Holcomb, Cherie; Rastrou, Melinda; Erlich, Henry; Tengesdal, Isak W; Dagna, Lorenzo; Neff, C Preston; Palmer, Brent E; Spritz, Richard A; Dinarello, Charles A

2016-02-02

Genetic risk for autoimmunity in HLA genes is most often attributed to structural specificity resulting in presentation of self-antigens. Autoimmune vitiligo is strongly associated with the MHC class II region. Here, we fine-map vitiligo MHC class II genetic risk to three SNPs only 47 bp apart, located within a predicted super-enhancer in an intergenic region between HLA-DRB1 and HLA-DQA1, localized by a genome-wide association study of 2,853 Caucasian vitiligo patients. The super-enhancer corresponds to an expression quantitative trait locus for expression of HLA-DR and HLA-DQ RNA; we observed elevated surface expression of HLA-DR (P = 0.008) and HLA-DQ (P = 0.02) on monocytes from healthy subjects homozygous for the high-risk SNP haplotype. Unexpectedly, pathogen-stimulated peripheral blood mononuclear cells from subjects homozygous for the high-risk super-enhancer haplotype exhibited greater increase in production of IFN-γ and IL-1β than cells from subjects homozygous for the low-risk haplotype. Specifically, production of IFN-γ on stimulation of dectin-1, mannose, and Toll-like receptors with Candida albicans and Staphylococcus epidermidis was 2.5- and 2.9-fold higher in high-risk subjects than in low-risk subjects, respectively (P = 0.007 and P = 0.01). Similarly, production of IL-1β was fivefold higher in high-risk subjects than in low-risk subjects (P = 0.02). Increased production of immunostimulatory cytokines in subjects carrying the high-risk haplotype may act as an "adjuvant" during the presentation of autoantigens, tying together genetic variation in the MHC with the development of autoimmunity. This study demonstrates that for risk of autoimmune vitiligo, expression level of HLA class II molecules is as or more important than antigen specificity.

Non-HLA antibodies post-transplantation: clinical relevance and treatment in solid organ transplantation.

Science.gov (United States)

Dragun, Duska; Hegner, Bjorn

2009-01-01

Antibodies and B cells are increasingly recognized as major modulators of allograft function and survival. Improved immunohistochemical and serologic diagnostic procedures have been developed to monitor antibody responses against HLA antigens during the last decade. Acute and chronic allograft rejection can occur in HLA-identical sibling transplants implicating the importance of immune response against non-HLA targets. Non-HLA anti-bodies may occur as alloantiboides, yet they seem to be predominantly autoantibodies. Antigenic targets of non-HLA antibodies described thus far include various minor histocompatibility antigens, vascular receptors, adhesion molecules, and intermediate filaments. Non-HLA antibodies may function as complement- and non-complement-fixing antibodies and they may induce a wide variety of allograft injuries, reflecting the complexity of their acute and chronic actions. Refined approaches considering the subtle mechanistic differences in the individual antibody responses directed against non-HLA antigens may help to define patients at particular risk for irreversible acute or chronic allograft injuries and improve over-all outcomes. We attempted to summarize the current state of research, development in diagnostic and therapeutic strategies, and to address some emerging problems in the area of humoral response against non-HLA antigens beyond ABO blood group and MHC class I chain-related gene A and B (MICA and MICB) antigens in solid organ transplantation. Copyright (c) 2009 S. Karger AG, Basel.

Spontaneous retinopathy in HLA-A29 transgenic mice

Science.gov (United States)

Szpak, Yann; Vieville, Jean-Claude; Tabary, Thierry; Naud, Marie-Christine; Chopin, Martine; Edelson, Catherine; Cohen, Jacques H. M.; Dausset, Jean; de Kozak, Yvonne; Pla, Marika

2001-01-01

Humans who have inherited the class I major histocompatibility allele HLA-A29 have a markedly increased relative risk of developing the eye disease termed birdshot chorioretinopathy. This disease affecting adults is characterized by symmetrically scattered, small, cream-colored spots in the fundus associated with retinal vasculopathy and inflammatory signs causing damage to the ocular structures, leading regularly to visual loss. To investigate the role of HLA-A29 in this disease, we introduced the HLA-A29 gene into mice. Aging HLA-A29 transgenic mice spontaneously developed retinopathy, showing a striking resemblance to the HLA-A29-associated chorioretinopathy. These results strongly suggest that HLA-A29 is involved in the pathogenesis of this disease. Elucidation of the role of HLA-A29 should be assisted by this transgenic model. PMID:11226280

Analysis of HLA-A, HLA-B, HLA-DRB1 allelic, genotypic, and haplotypic frequencies in colombian population

OpenAIRE

Yazmin Rocío Árias-Murillo; Miguel Ángel Castro-Jiménez; María Fernanda Ríos-Espinosa; Juan Javier López-Rivera; Sandra Johanna Echeverry-Coral; Oscar Martínez-Nieto

2010-01-01

Introduction: The high polymorphism of the HLA system allows its typification to be used as valuable tool in establishing association to various illnesses, immune and genetic profiles; it also provides a guide to identifying compatibility among donors and receptors of organs transplants. Objective: To establish HLA-A, HLA-B, and HLA.DRB1 allele, genotype and haplotype frequencies among patients treated at Clinica Colsanitas SA. Methods: 561 patients coming from different regions in Col...

Moving beyond HLA: a review of nHLA antibodies in organ transplantation.

Science.gov (United States)

Sigdel, Tara K; Sarwal, Minnie M

2013-11-01

Given the finite graft life expectancy of HLA identical organ transplants and the recognition of humoral graft injury in the absence of donor directed anti-HLA antibodies, the clinical impact of antibodies against non-HLA (nHLA) antigens in transplant injury is being increasingly recognized. The recognition of the impact of nHLA antigen discrepancies between donor and recipient on transplant outcomes is timely given the advances in rapid and lower cost sequencing methods that can soon provide complete maps of all recipient and donor HLA and nHLA mismatch data. In this review, we present a summary of recent reports evaluating the role of nHLA antibodies and their relevance to the field of organ transplantation. Copyright © 2013 American Society for Histocompatibility and Immunogenetics. Published by Elsevier Inc. All rights reserved.

Killing of targets by effector CD8 T cells in the mouse spleen follows the law of mass action

Energy Technology Data Exchange (ETDEWEB)

Ganusov, Vitaly V [Los Alamos National Laboratory

2009-01-01

In contrast with antibody-based vaccines, it has been difficult to measure the efficacy of T cell-based vaccines and to correlate the efficacy of CD8 T cell responses with protection again viral infections. In part, this difficulty is due to poor understanding of the in vivo efficacy of CD8 T cells produced by vaccination. Using a: recently developed experimental method of in vivo cytotoxicity we have investigated quantitative aspects of killing of peptide-pulsed targets by effector and memory CD8 T cells, specific to three epitopes of lymphocytic choriomeningitis virus (LCMV), in the mouse spleen. By analyzing data on killing of targets with varying number of epitope-specific effector and memory CD8 T cells, we find that killing of targets by effectors follows the law of mass-action, that is the death rate of peptide-pulsed targets is proportional to the frequency of CTLs in the spleen. In contrast, killing of targets by memory CD8 T cells does not follow the mass action law because the death rate of targets saturates at high frequencies of memory CD8 T cells. For both effector and memory cells, we also find little support for the killing term that includes the decrease of the death rate of targets with target cell density. Interestingly, our analysis suggests that at low CD8 T cell frequencies, memory CD8 T cells on the per capita basis are more efficient at killing peptide-pulsed targets than effectors, but at high frequencies, effectors are more efficient killers than memory T cells. Comparison of the estimated killing efficacy of effector T cells with the value that is predicted from theoretical physics and based on motility of T cells in lymphoid tissues, suggests that limiting step in the killing of peptide-pulsed targets is delivering the lethal hit and not finding the target. Our results thus form a basis for quantitative understanding of the process of killing of virus-infected cells by T cell responses in tissues and can be used to correlate the

Outside-in HLA class I signaling regulates ICAM-1 clustering and endothelial cell-monocyte interactions via mTOR in transplant antibody-mediated rejection.

Science.gov (United States)

Salehi, Sahar; Sosa, Rebecca A; Jin, Yi-Ping; Kageyama, Shoichi; Fishbein, Michael C; Rozengurt, Enrique; Kupiec-Weglinski, Jerzy W; Reed, Elaine F

2018-05-01

Antibody-mediated rejection (AMR) resulting in transplant allograft vasculopathy (TAV) is the major obstacle for long-term survival of solid organ transplants. AMR is caused by donor-specific antibodies to HLA, which contribute to TAV by initiating outside-in signaling transduction pathways that elicit monocyte recruitment to activated endothelium. Mechanistic target of rapamycin (mTOR) inhibitors can attenuate TAV; therefore, we sought to understand the mechanistic underpinnings of mTOR signaling in HLA class I Ab-mediated endothelial cell activation and monocyte recruitment. We used an in vitro model to assess monocyte binding to HLA I Ab-activated endothelial cells and found mTOR inhibition reduced ezrin/radixin/moesin (ERM) phosphorylation, intercellular adhesion molecule 1 (ICAM-1) clustering, and monocyte firm adhesion to HLA I Ab-activated endothelium. Further, in a mouse model of AMR, in which C57BL/6. RAG1 -/- recipients of BALB/c cardiac allografts were passively transferred with donor-specific MHC I antibodies, mTOR inhibition significantly reduced vascular injury, ERM phosphorylation, and macrophage infiltration of the allograft. Taken together, these studies indicate mTOR inhibition suppresses ERM phosphorylation in endothelial cells, which impedes ICAM-1 clustering in response to HLA class I Ab and prevents macrophage infiltration into cardiac allografts. These findings indicate a novel therapeutic application for mTOR inhibitors to disrupt endothelial cell-monocyte interactions during AMR. © 2017 The American Society of Transplantation and the American Society of Transplant Surgeons.

The production and crystallization of the human leukocyte antigen class II molecules HLA-DQ2 and HLA-DQ8 complexed with deamidated gliadin peptides implicated in coeliac disease

Energy Technology Data Exchange (ETDEWEB)

Henderson, Kate N.; Reid, Hugh H.; Borg, Natalie A.; Broughton, Sophie E.; Huyton, Trevor [The Protein Crystallography Unit, Department of Biochemistry and Molecular Biology, School of Biomedical Sciences, Monash University, Clayton, Victoria 3800 (Australia); Anderson, Robert P. [Autoimmunity and Transplantation Division, Walter and Eliza Hall Institute, 1G Royal Parade, Parkville, Victoria 3050 (Australia); Department of Gastroenterology, The Royal Melbourne Hospital, Grattan Street, Parkville, Victoria 3050 (Australia); McCluskey, James [Department of Microbiology and Immunology, University of Melbourne, Parkville, Victoria 3010 (Australia); Rossjohn, Jamie, E-mail: jamie.rossjohn@med.monash.edu.au [The Protein Crystallography Unit, Department of Biochemistry and Molecular Biology, School of Biomedical Sciences, Monash University, Clayton, Victoria 3800 (Australia)

2007-12-01

The production and crystallization of human leukocyte antigen class II molecules HLA-DQ2 and HLA-DQ8 in complex with deamidated gliadin peptides is reported. Crystals of HLA-DQ2{sup PQPELPYPQ} diffracted to 3.9 Å, while the HLA-DQ8{sup EGSFQPSQE} crystals diffracted to 2.1 Å, allowing structure determination by molecular replacement. The major histocompatibility complex (MHC) class II molecules HLA-DQ2 and HLA-DQ8 are key risk factors in coeliac disease, as they bind deamidated gluten peptides that are subsequently recognized by CD4{sup +} T cells. Here, the production and crystallization of both HLA-DQ2 and HLA-DQ8 in complex with the deamidated gliadin peptides DQ2 α-I (PQPELPYPQ) and DQ8 α-I (EGSFQPSQE), respectively, are reported.

Sulindac enhances the killing of cancer cells exposed to oxidative stress.

Directory of Open Access Journals (Sweden)

Maria Marchetti

2009-06-01

Full Text Available Sulindac is an FDA-approved non-steroidal anti-inflammatory drug (NSAID that affects prostaglandin production by inhibiting cyclooxygenases (COX 1 and 2. Sulindac has also been of interest for more than decade as a chemopreventive for adenomatous colorectal polyps and colon cancer.Pretreatment of human colon and lung cancer cells with sulindac enhances killing by an oxidizing agent such as tert-butyl hydroperoxide (TBHP or hydrogen peroxide. This effect does not involve cyclooxygenase (COX inhibition. However, under the conditions used, there is a significant increase in reactive oxygen species (ROS within the cancer cells and a loss of mitochondrial membrane potential, suggesting that cell death is due to apoptosis, which was confirmed by Tunel assay. In contrast, this enhanced killing was not observed with normal lung or colon cells.These results indicate that normal and cancer cells handle oxidative stress in different ways and sulindac can enhance this difference. The combination of sulindac and an oxidizing agent could have therapeutic value.

Time-kill profiles and cell-surface morphological effects of crude ...

African Journals Online (AJOL)

MK1201 mycelial extract on the viability and cell surface morphology of methicillin-susceptible Staphylococcus aureus (MSSA) and methicillin-resistant Staphylococcus aureus (MRSA). Methods: Time-kill assays were conducted by incubating test ...

Dynamical System Modeling to Simulate Donor T Cell Response to Whole Exome Sequencing-Derived Recipient Peptides Demonstrates Different Alloreactivity Potential in HLA-Matched and -Mismatched Donor-Recipient Pairs.

Science.gov (United States)

Abdul Razzaq, Badar; Scalora, Allison; Koparde, Vishal N; Meier, Jeremy; Mahmood, Musa; Salman, Salman; Jameson-Lee, Max; Serrano, Myrna G; Sheth, Nihar; Voelkner, Mark; Kobulnicky, David J; Roberts, Catherine H; Ferreira-Gonzalez, Andrea; Manjili, Masoud H; Buck, Gregory A; Neale, Michael C; Toor, Amir A

2016-05-01

Immune reconstitution kinetics and subsequent clinical outcomes in HLA-matched recipients of allogeneic stem cell transplantation (SCT) are variable and difficult to predict. Considering SCT as a dynamical system may allow sequence differences across the exomes of the transplant donors and recipients to be used to simulate an alloreactive T cell response, which may allow better clinical outcome prediction. To accomplish this, whole exome sequencing was performed on 34 HLA-matched SCT donor-recipient pairs (DRPs) and the nucleotide sequence differences translated to peptides. The binding affinity of the peptides to the relevant HLA in each DRP was determined. The resulting array of peptide-HLA binding affinity values in each patient was considered as an operator modifying a hypothetical T cell repertoire vector, in which each T cell clone proliferates in accordance with the logistic equation of growth. Using an iterating system of matrices, each simulated T cell clone's growth was calculated with the steady-state population being proportional to the magnitude of the binding affinity of the driving HLA-peptide complex. Incorporating competition between T cell clones responding to different HLA-peptide complexes reproduces a number of features of clinically observed T cell clonal repertoire in the simulated repertoire, including sigmoidal growth kinetics of individual T cell clones and overall repertoire, Power Law clonal frequency distribution, increase in repertoire complexity over time with increasing clonal diversity, and alteration of clonal dominance when a different antigen array is encountered, such as in SCT. The simulated, alloreactive T cell repertoire was markedly different in HLA-matched DRPs. The patterns were differentiated by rate of growth and steady-state magnitude of the simulated T cell repertoire and demonstrate a possible correlation with survival. In conclusion, exome wide sequence differences in DRPs may allow simulation of donor alloreactive T

The Cancer Exome Generated by Alternative mRNA Splicing Dilutes Predicted HLA Class I Epitope Density

DEFF Research Database (Denmark)

Stranzl, Thomas; Larsen, Mette Voldby; Lund, Ole

2012-01-01

Several studies have shown that cancers actively regulate alternative splicing. Altered splicing mechanisms in cancer lead to cancer-specific transcripts different from the pool of transcripts occurring only in healthy tissue. At the same time, altered presentation of HLA class I epitopes...... is frequently observed in various types of cancer. Down-regulation of genes related to HLA class I antigen processing has been observed in several cancer types, leading to fewer HLA class I antigens on the cell surface. Here, we use a peptidome wide analysis of predicted alternative splice forms, based...... on a publicly available database, to show that peptides over-represented in cancer splice variants comprise significantly fewer predicted HLA class I epitopes compared to peptides from normal transcripts. Peptides over-represented in cancer transcripts are in the case of the three most common HLA class I...

HLA typing in patients with multiple evanescent white dot syndrome (MEWDS).

Science.gov (United States)

Borruat, F X; Herbort, C P; Spertini, F; Desarnaulds, A B

1998-03-01

Multiple evanescent white dot syndrome (MEWDS) is an acquired chorioretinal disorder of unknown etiology. We investigated the possibility that MEWDS might be related to a specific HLA subtyping. Blood was obtained from nine patients affected by MEWDS. HLA-B51 was found in four of these nine patients with MEWDS. There was a 3.7-fold increased frequency of HLA-B51 in patients affected by MEWDS (relative risk 5.86). MEWDS might then be related to the presence of a specific HLA subtype, HLA-B51. However, due to the small sample size, our results need to be confirmed by further testing.

The link between CD8⁺ T-cell antigen-sensitivity and HIV-suppressive capacity depends on HLA restriction, target epitope and viral isolate.

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Lissina, Anna; Fastenackels, Solène; Inglesias, Maria C; Ladell, Kristin; McLaren, James E; Briceño, Olivia; Gostick, Emma; Papagno, Laura; Autran, Brigitte; Sauce, Delphine; Price, David A; Saez-Cirion, Asier; Appay, Victor

2014-02-20

Although it is established that CD8 T-cell immunity is critical for the control of HIV replication in vivo, the key factors that determine antiviral efficacy are yet to be fully elucidated. Antigen-sensitivity and T-cell receptor (TCR) avidity have been identified as potential determinants of CD8⁺ T-cell efficacy. However, there is no general consensus in this regard because the relationship between these parameters and the control of HIV infection has been established primarily in the context of immunodominant CD8⁺ T-cell responses against the Gag₂₆₃₋₂₇₂ KK10 epitope restricted by human leukocyte antigen (HLA)-B27. To investigate the relationship between antigen-sensitivity, TCR avidity and HIV-suppressive capacity in vitro across epitope specificities and HLA class I restriction elements, we used a variety of techniques to study CD8⁺ T-cell clones specific for Nef₇₃₋₈₂ QK10 and Gag₂₀₋₂₉ RY10, both restricted by HLA-A3, alongside CD8⁺ T-cell clones specific for Gag₂₆₃₋₂₇₂ KK10. For each targeted epitope, the linked parameters of antigen-sensitivity and TCR avidity correlated directly with antiviral efficacy. However, marked differences in HIV-suppressive capacity were observed between epitope specificities, HLA class I restriction elements and viral isolates. Collectively, these data emphasize the central role of the TCR as a determinant of CD8⁺ T-cell efficacy and demonstrate that the complexities of antigen recognition across epitope and HLA class I boundaries can confound simple relationships between TCR engagement and HIV suppression.

HLA-DR-specific suppressor cells after repeated allogeneic sensitizations of human lymphocytes in vitro

International Nuclear Information System (INIS)

Sasportes, M.; Fradelizi, D.; Dausset, J.

1978-01-01

In conclusion, DR-specific suppressor cells can be induced by repeated in vitro sensitizations. They were able to decrease a secondary proliferation, to suppress consistently, in a primary proliferative assay, when added as third cells (primed twice against a DR antigen [PLT II] and γ-irradiated), the response of unprimed cells towards stimulating cells, which share a DR specificity with the priming cell of the PLT II. The suppression follows the D part of the recombinant haplotype within an HLA-B/D recombinant family and is specific for the DR antigen used twice as stimulator for production of the PLT II

Deciphering allogeneic antibody response against native and denatured HLA epitopes in organ transplantation.

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Visentin, Jonathan; Guidicelli, Gwendaline; Moreau, Jean-François; Lee, Jar-How; Taupin, Jean-Luc

2015-07-01

Anti-HLA donor-specific antibodies are deleterious for organ transplant survival. Class I HLA donor-specific antibodies are identified by using the Luminex single antigen beads (LSAB) assay, which also detects anti-denatured HLA antibodies (anti-dHLAs). Anti-dHLAs are thought to be unable to recognize native HLA (nHLA) on the cell surface and therefore to be clinically irrelevant. Acid denaturation of nHLA on LSAB allows anti-dHLAs to be discriminated from anti-nHLAs. We previously defined a threshold for the ratio between mean fluorescence intensity against acid-treated (D for denaturation) and nontreated (N) LSAB, D ≥ 1.2 N identifying the anti-dHLAs. However, some anti-dHLAs remained able to bind nHLA on lymphocytes in flow cytometry crossmatches, and some anti-nHLAs conserved significant reactivity toward acid-treated LSAB. After depleting serum anti-nHLA reactivity with HLA-typed cells, we analyzed the residual LSAB reactivity toward nontreated and acid-treated LSABs, and then evaluated the ability of antibodies to recognize nHLA alleles individually. We observed that sera can contain mixtures of anti-nHLAs and anti-dHLAs, or anti-nHLAs recognizing acid-resistant epitopes, all possibly targeting the same allele(s). Therefore, the anti-HLA antibody response can be highly complex and subtle, as is the accurate identification of pathogenic anti-HLA antibodies in human serum. © 2015 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

Generation of functional HLA-DR*1101 tetramers receptive for loading with pathogen or tumour derived synthetic peptides

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Protti Maria

2005-12-01

Full Text Available Abstract Background MHC class I-peptide tetramers are currently utilised to characterize CD8+ T cell responses at single cell level. The generation and use of MHC class II tetramers to study antigen-specific CD4+ T cells appears less straightforward. Most MHC class II tetramers are produced with a homogeneously built-in peptide, reducing greatly their flexibility of use. We attempted the generation of "empty" functional HLA-DR*1101 tetramers, receptive for loading with synthetic peptides by incubation. No such reagent is in fact available for this HLA-DR allele, one of the most frequent in the Caucasian population. Results We compared soluble MHC class II-immunoglobulin fusion proteins (HLA-DR*1101-Ig with soluble MHC class II protein fused with an optimised Bir site for enzymatic biotynilation (HLA-DR*1101-Bir, both produced in insect cells. The molecules were multimerised by binding fluorochrome-protein A or fluorochrome-streptavidin, respectively. We find that HLA-DR*1101-Bir molecules are superior to the HLA-DR*1101-Ig ones both in biochemical and functional terms. HLA-DR*1101-Bir molecules can be pulsed with at least three different promiscuous peptide epitopes, derived from Tetanus Toxoid, influenza HA and the tumour associated antigen MAGE-3 respectively, to stain specific CD4+ T cells. Both staining temperature and activation state of CD4+ T cells are critical for the binding of peptide-pulsed HLA-DR*1101-Bir to the cognate TCR. Conclusion It is therefore possible to generate a soluble recombinant HLA-DR*1101 backbone that is receptive for loading with different peptides to stain specific CD4+ T cells. As shown for other HLA-DR alleles, we confirm that not all the strategies to produce soluble HLA-DR*1101 multimers are equivalent.

NK-cell-dependent killing of colon carcinoma cells is mediated by natural cytotoxicity receptors (NCRs) and stimulated by parvovirus infection of target cells

International Nuclear Information System (INIS)

Bhat, Rauf; Rommelaere, Jean

2013-01-01

Investigating how the immune system functions during malignancies is crucial to developing novel therapeutic strategies. Natural killer (NK) cells, an important component of the innate immune system, play a vital role in immune defense against tumors and virus-infected cells. The poor survival rate in colon cancer makes it particularly important to develop novel therapeutic strategies. Oncolytic viruses, in addition to lysing tumor cells, may have the potential to augment antitumor immune responses. In the present study, we investigate the role of NK cells and how parvovirus H-1PV can modulate NK-cell mediated immune responses against colon carcinoma. Human NK cells were isolated from the blood of healthy donors. The cytotoxicity and antibody-mediated inhibition of NK cells were measured in chromium release assays. Phenotypic assessment of colon cancer and dendritic cells was done by FACS. The statistical significance of the results was calculated with Student’s t test (*p <0.05; **, p < 0.01; ***, p < 0.001). We show that IL-2-activated human NK cells can effectively kill colon carcinoma cells. Killing of colon carcinoma cells by NK cells was further enhanced upon infection of the former cells with parvovirus H-1PV. H-1PV has potent oncolytic activity against various tumors, yet its direct killing effect on colon carcinoma cells is limited. The cytotoxicity of NK cells towards colon carcinoma cells, both mock- and H-1PV-infected, was found to be mostly mediated by a combination of natural cytotoxicity receptors (NCRs), namely NKp30, 44, and 46. Colon carcinoma cells displayed low to moderate expression of NK cell ligands, and this expression was modulated upon H-1PV infection. Lysates of H-1PV-infected colon carcinoma cells were found to increase MHC class II expression on dendritic cells. Altogether, these data suggest that IL-2-activated NK cells actively kill colon carcinoma cells and that this killing is mediated by several natural cytotoxicity receptors

Bystander Host Cell Killing Effects of Clostridium perfringens Enterotoxin

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Archana Shrestha

2016-12-01

Full Text Available Clostridium perfringens enterotoxin (CPE binds to claudin receptors, e.g., claudin-4, and then forms a pore that triggers cell death. Pure cultures of host cells that do not express claudin receptors, e.g., fibroblasts, are unaffected by pathophysiologically relevant CPE concentrations in vitro. However, both CPE-insensitive and CPE-sensitive host cells are present in vivo. Therefore, this study tested whether CPE treatment might affect fibroblasts when cocultured with CPE-sensitive claudin-4 fibroblast transfectants or Caco-2 cells. Under these conditions, immunofluorescence microscopy detected increased death of fibroblasts. This cytotoxic effect involved release of a toxic factor from the dying CPE-sensitive cells, since it could be reproduced using culture supernatants from CPE-treated sensitive cells. Supernatants from CPE-treated sensitive cells, particularly Caco-2 cells, were found to contain high levels of membrane vesicles, often containing a CPE species. However, most cytotoxic activity remained in those supernatants even after membrane vesicle depletion, and CPE was not detected in fibroblasts treated with supernatants from CPE-treated sensitive cells. Instead, characterization studies suggest that a major cytotoxic factor present in supernatants from CPE-treated sensitive cells may be a 10- to 30-kDa host serine protease or require the action of that host serine protease. Induction of caspase-3-mediated apoptosis was found to be important for triggering release of the cytotoxic factor(s from CPE-treated sensitive host cells. Furthermore, the cytotoxic factor(s in these supernatants was shown to induce a caspase-3-mediated killing of fibroblasts. This bystander killing effect due to release of cytotoxic factors from CPE-treated sensitive cells could contribute to CPE-mediated disease.

The Case for High Resolution Extended 6-Loci HLA Typing for Identifying Related Donors in the Indian Subcontinent.

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Agarwal, Rajat Kumar; Kumari, Ankita; Sedai, Amit; Parmar, Lalith; Dhanya, Rakesh; Faulkner, Lawrence

2017-09-01

Three-loci low-resolution (LR) or intermediate-resolution HLA typing is generally considered adequate in the related blood and marrow transplantation (BMT) context. However, a single high-resolution (HR) mismatch may have a similar adverse impact on BMT outcome as an LR one. We sought to determine the frequency of mismatches that may go undetected when standard typing (LR or 3-loci HR) is used compared with 6-loci HR typing for related donor compatibility testing, and to assess its impact on relevant BMT outcomes. We analyzed data from a total of 2554 6-loci (HLA-A, -B, -C, -DRB1, -DQB1, and -DPB1) HR sequence-based typing (full typing [FT]) from 754 patients, 1011 siblings, and 789 parents done at DKMS Germany (www.DKMS.de) between January 1, 2014, and June 21, 2016. We also studied 38 cases in which the family had undergone 3-loci HLA typing (standard typing [ST]). Patients were from India (70%), Pakistan (22%), and Sri Lanka (8%). The IMGT/HLA database (www.ebi.ac.uk/ipd/imgt/hla) was used to tease out nonpermissive DPB1 mismatches. HLA disparity-related outcomes, such as rejection and graft-versus-host disease (GVHD) were assessed in a retrospective matched-pair cohort of 50 patients (25 with ST and 25 with FT) who underwent BMT for severe thalassemia from compatible related donors. We found fully matched (either 12/12 HR matches or with a single permissive DPB1 mismatch) related donors for 285 patients (38%). Of these donors, 89% were siblings and 11% were parents. The likelihood of matching on an individual locus on LR but not on HR was found to be 5%. A total of 9 donors (3%; 7 siblings and 2 parents) who would have been considered a full match by HR typing on A, B, and DRB1 alone were not a match by extended 6-loci HR typing. Five of these 9 donors had a mismatch on C or DQB1, and 4 had a nonpermissive DPB1 mismatch. In this group, 5 donors (56%) belonged to a consanguineous family, in 2 donors (22%) there was no reported consanguinity, and in 2 donors (22

Killing malignant melanoma cells with protoporphyrin IX-loaded polymersome-mediated photodynamic therapy and cold atmospheric plasma

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Wang M

2017-05-01

Full Text Available Mian Wang,1 Benjamin M Geilich,2 Michael Keidar,3 Thomas J Webster1,4 1Department of Chemical Engineering, 2Department of Bioengineering, Northeastern University, Boston, MA, 3Department of Mechanical and Aerospace Engineering, George Washington University, Washington, DC, USA; 4Wenzhou Institute of Biomaterials and Engineering, Wenzhou Medical University, Wenzhou, People’s Republic of China Abstract: Traditional cancer treatments contain several limitations such as incomplete ablation and multidrug resistance. It is known that photodynamic therapy (PDT is an effective treatment for several tumor types especially melanoma cells. During the PDT process, protoporphyrin IX (PpIX, an effective photosensitizer, can selectively kill cancer cells by activating a special light source. When tumor cells encapsulate a photosensitizer, they can be easily excited into an excited state by a light source. In this study, cold atmospheric plasma (CAP was used as a novel light source. Results of some studies have showed that cancer cells can be effectively killed by using either a light source or an individual treatment due to the generation of reactive oxygen species and electrons from a wide range of wavelengths, which suggest that CAP can act as a potential light source for anticancer applications compared with UV light sources. Results of the present in vitro study indicated for the first time that PpIX can be successfully loaded into polymersomes. Most importantly, cell viability studies revealed that PpIX-loaded polymersomes had a low toxicity to healthy fibroblasts (20% were killed at a concentration of 400 µg/mL, but they showed a great potential to selectively kill melanoma cells (almost 50% were killed. With the application of CAP posttreatment, melanoma cell viability significantly decreased (80% were killed compared to not using a light source (45% were killed or using a UV light source (65% were killed. In summary, these results indicated for the

Caffeine enhancement of x-ray killing in cultured human and rodent cells

International Nuclear Information System (INIS)

Waldren, C.A.; Rasko, I.

1978-01-01

A 16 to 20 hr postirradiation incubation with caffeine enhances x-ray killing of rodent and human cells. Cells tested were Chinese hamster ovary (CHO-K1), lung (CHL), V79, mouse L, HeLa S3, human fibroblasts (AF288, TC171, FS9, CRL1166), and a human-hamster hybrid. The effect of caffeine on the x-ray survival curve of these cells was to remove the initial shoulder without significantly altering the mean lethal dose (D 0 ). This action can be achieved at caffeine concentrations which of themselves cause less than 15% killing. In randomly growing CHO-K1 cells the caffeine-sensitive process occurs with a half-time of 2 to 5 hr after irradiation. These experiments indicate the existence in human and rodent cells of caffeine-inhibited genome repair for x-ray damage

CD47-CAR-T Cells Effectively Kill Target Cancer Cells and Block Pancreatic Tumor Growth.

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Golubovskaya, Vita; Berahovich, Robert; Zhou, Hua; Xu, Shirley; Harto, Hizkia; Li, Le; Chao, Cheng-Chi; Mao, Mike Ming; Wu, Lijun

2017-10-21

CD47 is a glycoprotein of the immunoglobulin superfamily that is often overexpressed in different types of hematological and solid cancer tumors and plays important role in blocking phagocytosis, increased tumor survival, metastasis and angiogenesis. In the present report, we designed CAR (chimeric antigen receptor)-T cells that bind CD47 antigen. We used ScFv (single chain variable fragment) from mouse CD47 antibody to generate CD47-CAR-T cells for targeting different cancer cell lines. CD47-CAR-T cells effectively killed ovarian, pancreatic and other cancer cells and produced high level of cytokines that correlated with expression of CD47 antigen. In addition, CD47-CAR-T cells significantly blocked BxPC3 pancreatic xenograft tumor growth after intratumoral injection into NSG mice. Moreover, we humanized mouse CD47 ScFv and showed that it effectively bound CD47 antigen. The humanized CD47-CAR-T cells also specifically killed ovarian, pancreatic, and cervical cancer cell lines and produced IL-2 that correlated with expression of CD47. Thus, CD47-CAR-T cells can be used as a novel cellular therapeutic agent for treating different types of cancer.

Comparing Effects of BK Virus Agnoprotein and Herpes Simplex-1 ICP47 on MHC-I and MHC-II Expression

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Michela Cioni

2013-01-01

Full Text Available Background. Among human polyomaviruses, only BK virus (BKV and JC virus (JCV encode an agnoprotein upstream of VP1 on the viral late transcript. BKV agnoprotein is abundantly expressed late in the viral life cycle, but specific cellular and humoral immune responses are low or absent. We hypothesized that agnoprotein might contribute to BKV immune evasion by downregulating HLA expression, similar to Herpes simplex virus-1 ICP47. Methods UTA-6 or primary human renal proximal tubular epithelial cells (RPTEC were co-transfected with plasmids constitutively expressing agnoprotein, or ICP47, and enhanced green-fluorescent protein (EGFP. EGFP-gated cells were analyzed for HLA-ABC and HLA-DR expression by flow cytometry. HLA-ABC and HLA-DR expression was also analyzed on UTA-6 bearing tetracycline-regulated agnoprotein or ICP47. Effects of agnoprotein on viral peptide-dependent T-cell killing were investigated using 51Cr release. Results. ICP47 downregulated HLA-ABC without affecting HLA-DR, whereas agnoprotein did not affect HLA-ABC or HLA-DR expression. Interferon-γ treatment increased HLA-ABC in a dose-dependent manner, which was antagonized by ICP47, but not by agnoprotein. In UTA-6 cells, agnoprotein expression did neither impair HLA-ABC or -DR expression nor peptide-specific killing impaired by HLA-matched T-cells. Conclusion. Unlike the HSV-1 ICP47, BKV agnoprotein does not contribute to viral immune evasion by down-regulating HLA-ABC, or interfere with HLA-DR expression or peptide-dependent T-cell cytotoxicity.

HIV subtype influences HLA-B*07:02-associated HIV disease outcome

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Kløverpris, Henrik N; Adland, Emily; Koyanagi, Madoka

2014-01-01

Genetic polymorphisms within the MHC encoding region have the strongest impact on HIV disease progression of any in the human genome and provide important clues to the mechanisms of HIV immune control. Few analyses have been undertaken of HLA alleles associated with rapid disease progression. HLA......% versus 43% in HLA-B*07:02-negative subjects). These data support earlier studies suggesting that increased breadth of the Gag-specific CD8(+) T cell response may contribute to improved HIV immune control irrespective of the particular HLA molecules expressed....

Clinicopathologic significance of HLA-G and HLA-E molecules in Tunisian patients with ovarian carcinoma.

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Babay, Wafa; Ben Yahia, Hamza; Boujelbene, Nadia; Zidi, Nour; Laaribi, Ahmed Baligh; Kacem, Dhikra; Ben Ghorbel, Radhia; Boudabous, Abdellatif; Ouzari, Hadda-Imene; Rizzo, Roberta; Rebmann, Vera; Mrad, Karima; Zidi, Inès

2018-06-01

The human leukocyte antigen (HLA)-G and HLA-E, non classical HLA class I molecules, have been highly implicated in immune tolerance. HLA-G and HLA-E molecules were proposed as putative markers of several advanced cancers. As a step towards a better understanding of ovarian carcinoma, we evaluated the expression of both HLA-G and HLA-E molecules and explored their prognostic implication. HLA-G and HLA-E expression were studied by immunohistochemistry on ovarian carcinoma tissues. This expression was semi-quantitatively scored into four expression groups and correlated to clinicopathological parameters and patients' survival. HLA-G and HLA-E have been found to be highly expressed in ovarian carcinoma tissues (Respectively, 72.4% and 96.8%). They are frequently co-expressed. Univariate and multivariate analysis revealed that a positive HLA-G expression status in tumor tissue is a promising candidate parameter to predict disease recurrence in addition to the disease status in Tunisian patients with ovarian carcinoma. Moreover, the elevated HLA-E expression was associated with serous ovarian carcinoma subtype as well as with advanced stages of ovarian carcinoma. HLA-G and HLA-E are highly represented in ovarian carcinoma suggesting a potential association with progressive disease mechanism. HLA-G and HLA-E molecules might be new candidates' markers for ovarian carcinoma progression. Copyright © 2018 American Society for Histocompatibility and Immunogenetics. Published by Elsevier Inc. All rights reserved.

Moving Beyond HLA: A Review of nHLA Antibodies in Organ Transplantation

OpenAIRE

Sigdel, Tara K.; Sarwal, Minnie M.

2013-01-01

Given the finite graft life expectancy of HLA identical organ transplants and the recognition of humoral graft injury in the absence of donor directed anti-HLA antibodies, the clinical impact of antibodies against non-HLA (nHLA) antigens in transplant injury is being increasingly recognized. The recognition of the impact of nHLA antigen discrepancies between donor and recipient on transplant outcomes is timely given the advances in rapid and lower cost sequencing methods that can soon provide...

HLA typing in acute optic neuritis. Relation to multiple sclerosis and magnetic resonance imaging findings

DEFF Research Database (Denmark)

Frederiksen, J.L.; Madsen, H.O.; Ryder, L.P.

1997-01-01

OBJECTIVE: To study the association of brain magnetic resonance imaging (MRI) findings and HLA findings to clarify the relationship between monosymptomatic optic neuritis (ON) and ON as part of clinically definite multiple sclerosis (CDMS). DESIGN: Population-based cohort of patients with ON refe......OBJECTIVE: To study the association of brain magnetic resonance imaging (MRI) findings and HLA findings to clarify the relationship between monosymptomatic optic neuritis (ON) and ON as part of clinically definite multiple sclerosis (CDMS). DESIGN: Population-based cohort of patients......: The frequency of HLA-DR15 was significantly increased in patients with ON + CDMS (52%) and ON (47%) compared with control subjects (31%). The frequency of HLA-DR17 was almost equal in the ON + CDMS (18%), ON (23%), and control (23%) groups. The frequencies of HLA-DQA-1B (55% in ON + CDMS, 58% in ON) and HLA...

HLA Association with Drug-Induced Adverse Reactions

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Wen-Lang Fan

2017-01-01

Full Text Available Adverse drug reactions (ADRs remain a common and major problem in healthcare. Severe cutaneous adverse drug reactions (SCARs, such as Stevens–Johnson syndrome (SJS/toxic epidermal necrolysis (TEN with mortality rate ranges from 10% to more than 30%, can be life threatening. A number of recent studies demonstrated that ADRs possess strong genetic predisposition. ADRs induced by several drugs have been shown to have significant associations with specific alleles of human leukocyte antigen (HLA genes. For example, hypersensitivity to abacavir, a drug used for treating of human immunodeficiency virus (HIV infection, has been proposed to be associated with allele 57:01 of HLA-B gene (terms HLA-B∗57:01. The incidences of abacavir hypersensitivity are much higher in Caucasians compared to other populations due to various allele frequencies in different ethnic populations. The antithyroid drug- (ATDs- induced agranulocytosis are strongly associated with two alleles: HLA-B∗38:02 and HLA-DRB1∗08:03. In addition, HLA-B∗15:02 allele was reported to be related to carbamazepine-induced SJS/TEN, and HLA-B∗57:01 in abacavir hypersensitivity and flucloxacillin induced drug-induced liver injury (DILI. In this review, we summarized the alleles of HLA genes which have been proposed to have association with ADRs caused by different drugs.

Pre-existing anti-HLA antibodies negatively impact survival of pediatric aplastic anemia patients undergoing HSCT.

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Zhu, Hua; He, Jun; Cai, Junchao; Yuan, Xiaoni; Jiang, Hua; Luo, Changying; Wang, Jianmin; Luo, Chengjuan; Pan, Zhijuan; Terasaki, Paul I; Ding, Lixia; Chen, Jing

2014-11-01

Graft failure and survival are the major problems for patients with aplastic anemia undergoing hematopoietic stem cell transplantation (HSCT). Previous studies showed that anti-HLA antibodies negatively impact engraftment in HSCT. This retrospective study of 51 pediatric patients with acquired aplastic anemia who underwent allogeneic HSCT at a single institution between 2006 and 2012 investigated the influence of anti-HLA antibodies on the outcome of HSCT. Serum samples collected before HSCT were tested for the presence of anti-HLA antibodies. Pre-existing anti-HLA antibodies were detected in 54.9% (28/51) of patients, among whom 39.2% (20/51) had anti-HLA class I antibodies. Anti-HLA antibodies were associated with worse five-yr survival (78.6% vs. 100%, p = 0.021) and higher treatment-related mortality (21.4% vs. 0%, p = 0.028) compared with antibody-negative patients. Anti-HLA class I antibody-positive patients had poorer five-yr survival (75.0%) than anti-HLA class I&II antibody-positive and antibody-negative patients (87.5% and 100.0%, respectively, p = 0.039). Presence of anti-HLA class I antibodies (p = 0.024) and older age (10 yr or more; p = 0.027) significantly increased the risk of post-HSCT mortality. Pre-existing anti-HLA antibodies negatively affect the outcome of HSCT in pediatric patients with aplastic anemia. Routine testing for anti-HLA antibodies concurrent with efficient treatment should be conducted prior to HSCT. © 2014 John Wiley & Sons A/S. Published by John Wiley & Sons Ltd.

Association between HLA-DQA1, HLA-DQB1 and oral cancer

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Sheng-Chien Tsai

2011-10-01

Full Text Available Cancer is one of the most common causes of morbidity and mortality. Genes whose products play a critical role in regulation of the immune response include the HLA antigen and cytokine families of genes. Oral cancer is common in men in developing countries, and its frequency is increased by using betel-quid, tobacco, and alcohol. The association between certain HLA Class I and Class II haplotypes and cancer has been documented in a variety of tumors. There was no previous data concerning the association of specific HLA Class II DQA1, DQB1 alleles, or haplotypes with oral cancer patients. In this study, we enrolled 134 Taiwanese patients with histologically confirmed oral cancer and 268 age- and gender-matched healthy Taiwanese adults as control group to investigate the association between HLA-DQA1, HLA-DQB1 allele frequencies and oral cancer patients by using polymerase chain reaction with sequence-specific primers. We found that both HLA-DQA1* and HLA-DQB1* allele frequencies in oral cancer patients revealed no significant difference from those of control groups. Haplotype frequencies of HLA*DQA1-0103-DQB1*0601 in oral cancer patients were significantly lower than those of the control group (odds ratio: 0.18, 95% confidence interval: 0.054–0.583, pc=0.02. Our data suggest that HLA DQA1*0103-DQB1*0601 haplotype may be protective with regard to the development of oral cancer.

The impact of HLA matching on long-term transplant outcome after allogeneic hematopoietic stem cell transplantation for CLL: a retrospective study from the EBMT registry

DEFF Research Database (Denmark)

Michallet, M; Sobh, M; Milligan, D

2010-01-01

We analyzed 368 chronic lymphocytic leukemia patients who underwent allogeneic hematopoietic stem cell transplantation reported to the EBMT registry between 1995 and 2007. There were 198 human leukocyte antigen (HLA)-identical siblings; among unrelated transplants, 31 were well matched in high...... worsened significantly when EBMT risk score increased. HLA matching had no significant impact on relapse (siblings: 24% (21-27); WMUD: 35% (26-44), P=0.11 and MM: 21% (18-24), P=0.81); alemtuzumab T-cell depletion and stem cell source (peripheral blood) were associated with an increased risk. Our findings...... support the use of WMUD as equivalent alternative to HLA-matched sibling donors for allogeneic HSCT in CLL, and justify the application of EBMT risk score in this disease....

DNA-repair, cell killing and normal tissue damage

International Nuclear Information System (INIS)

Dahm-Daphi, J.; Dikomey, E.; Brammer, I.

1998-01-01

Background: Side effects of radiotherapy in normal tissue is determined by a variety of factors of which cellular and genetic contributions are described here. Material and methods: Review. Results: Normal tissue damage after irradiation is largely due to loss of cellular proliferative capacity. This can be due to mitotic cell death, apoptosis, or terminal differentiation. Dead or differentiated cells release cytokines which additionally modulate the tissue response. DNA damage, in particular non-reparable or misrepaired double-strand breaks are considered the basic lesion leading to G1-arrest and ultimately to cell inactivation. Conclusion: Evidence for genetic bases of normal tissue response, cell killing and DNA-repair capacity is presented. However, a direct link of all 3 endpoints has not yet been proved directly. (orig.) [de

Long-term control of HIV-1 in hemophiliacs carrying slow-progressing allele HLA-B*5101.

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Kawashima, Yuka; Kuse, Nozomi; Gatanaga, Hiroyuki; Naruto, Takuya; Fujiwara, Mamoru; Dohki, Sachi; Akahoshi, Tomohiro; Maenaka, Katsumi; Goulder, Philip; Oka, Shinichi; Takiguchi, Masafumi

2010-07-01

HLA-B*51 alleles are reported to be associated with slow disease progression to AIDS, but the mechanism underlying this association is still unclear. In the present study, we analyzed the effect of HLA-B*5101 on clinical outcome for Japanese hemophiliacs who had been infected with HIV-1 before 1985 and had been recruited in 1998 for this study. HLA-B*5101(+) hemophiliacs exhibited significantly slow progression. The analysis of HLA-B*5101-restricted HIV-1-specific cytotoxic T-lymphocyte (CTL) responses to 4 HLA-B*-restricted epitopes in 10 antiretroviral-therapy (ART)-free HLA-B*5101(+) hemophiliacs showed that the frequency of Pol283-8-specific CD8(+) T cells was inversely correlated with the viral load, whereas the frequencies of CD8(+) T cells specific for 3 other epitopes were positively correlated with the viral load. The HLA-B*5101(+) hemophiliacs whose HIV-1 replication had been controlled for approximately 25 years had HIV-1 possessing the wild-type Pol283-8 sequence or the Pol283-8V mutant, which does not critically affect T-cell recognition, whereas other HLA-B*5101(+) hemophiliacs had HIV-1 with escape mutations in this epitope. The results suggest that the control of HIV-1 over approximately 25 years in HLA-B*5101-positive hemophiliacs is associated with a Pol283-8-specific CD8(+) T-cell response and that lack of control of HIV-1 is associated with the appearance of Pol283-8-specific escape mutants.

Outcome of children with acute leukemia given HLA-haploidentical HSCT after αβ T-cell and B-cell depletion.

Science.gov (United States)

Locatelli, Franco; Merli, Pietro; Pagliara, Daria; Li Pira, Giuseppina; Falco, Michela; Pende, Daniela; Rondelli, Roberto; Lucarelli, Barbarella; Brescia, Letizia Pomponia; Masetti, Riccardo; Milano, Giuseppe Maria; Bertaina, Valentina; Algeri, Mattia; Pinto, Rita Maria; Strocchio, Luisa; Meazza, Raffaella; Grapulin, Lavinia; Handgretinger, Rupert; Moretta, Alessandro; Bertaina, Alice; Moretta, Lorenzo

2017-08-03

Allogeneic hematopoietic stem cell transplantation (HSCT) from an HLA-haploidentical relative (haplo-HSCT) is a suitable option for children with acute leukemia (AL) either relapsed or at high-risk of treatment failure. We developed a novel method of graft manipulation based on negative depletion of αβ T and B cells and conducted a prospective trial evaluating the outcome of children with AL transplanted with this approach. Eighty AL children, transplanted between September 2011 and September 2014, were enrolled in the trial. All children were given a fully myeloablative preparative regimen. Anti-T-lymphocyte globulin from day -5 to -3 was used for preventing graft rejection and graft-versus-host disease (GVHD); no patient received any posttransplantation GVHD prophylaxis. Two children experienced primary graft failure. The cumulative incidence of skin-only, grade 1-2 acute GVHD was 30%; no patient developed extensive chronic GVHD. Four patients died, the cumulative incidence of nonrelapse mortality being 5%, whereas 19 relapsed, resulting in a 24% cumulative incidence of relapse. With a median follow-up of 46 months for surviving patients, the 5-year probability of chronic GVHD-free, relapse-free survival (GRFS) is 71%. Total body irradiation-containing preparative regimen was the only variable favorably influencing relapse incidence and GRFS. The outcomes of these 80 patients are comparable to those of 41 and 51 children given transplantation from an HLA-identical sibling or a 10/10 allelic-matched unrelated donor in the same period. These data indicate that haplo-HSCT after αβ T- and B-cell depletion represents a competitive alternative for children with AL in need of urgent allograft. This trial was registered at www.clinicaltrials.gov as #NCT01810120. © 2017 by The American Society of Hematology.

Glycan elongation beyond the mucin associated Tn antigen protects tumor cells from immune-mediated killing.

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Caroline B Madsen

Full Text Available Membrane bound mucins are up-regulated and aberrantly glycosylated during malignant transformation in many cancer cells. This results in a negatively charged glycoprotein coat which may protect cancer cells from immune surveillance. However, only limited data have so far demonstrated the critical steps in glycan elongation that make aberrantly glycosylated mucins affect the interaction between cancer cells and cytotoxic effector cells of the immune system. Tn (GalNAc-Ser/Thr, STn (NeuAcα2-6GalNAc-Ser/Thr, T (Galβ1-3GalNAc-Ser/Thr, and ST (NeuAcα2-6Galβ1-3GalNAc-Ser/Thr antigens are recognized as cancer associated truncated glycans, and are expressed in many adenocarcinomas, e.g. breast- and pancreatic cancer cells. To investigate the role of the cancer associated glycan truncations in immune-mediated killing we created glyco-engineered breast- and pancreatic cancer cells expressing only the shortest possible mucin-like glycans (Tn and STn. Glyco-engineering was performed by zinc finger nuclease (ZFN knockout (KO of the Core 1 enzyme chaperone COSMC, thereby preventing glycan elongation beyond the initial GalNAc residue in O-linked glycans. We find that COSMC KO in the breast and pancreatic cancer cell lines T47D and Capan-1 increases sensitivity to both NK cell mediated antibody-dependent cellular-cytotoxicity (ADCC and cytotoxic T lymphocyte (CTL-mediated killing. In addition, we investigated the association between total cell surface expression of MUC1/MUC16 and NK or CTL mediated killing, and observed an inverse correlation between MUC16/MUC1 expression and the sensitivity to ADCC and CTL-mediated killing. Together, these data suggest that up-regulation of membrane bound mucins protects cells from immune mediated killing, and that particular glycosylation steps, as demonstrated for glycan elongation beyond Tn and STn, can be important for fine tuning of the immune escape mechanisms in cancer cells.

In Silico Derivation of HLA-Specific Alloreactivity Potential from Whole Exome Sequencing of Stem Cell Transplant Donors and Recipients: Understanding the Quantitative Immunobiology of Allogeneic Transplantation

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Max eJameson-Lee

2014-11-01

Full Text Available Donor T cell mediated graft versus host effects (GVH may result from the aggregate alloreactivity to minor histocompatibility antigens (mHA presented by the HLA molecules in each donor-recipient pair undergoing stem cell transplantation (SCT. Whole exome sequencing has previously demonstrated a large number of nonsynonymous single nucleotide polymorphisms (SNP present in HLA-matched recipients of SCT donors (GVH direction. The nucleotide sequence flanking each of these SNPs was obtained and the amino acid sequence determined. All the possible nonameric-peptides incorporating the variant amino acid resulting from these SNPs were interrogated in-silico for their likelihood to be presented by the HLA class I molecules using the Immune Epitope Database stabilized matrix method (SMM and NetMHCpan algorithms. The SMM algorithm predicted that a median of 18,396 peptides weakly bound HLA class I molecules in individual SCT recipients, and 2,254 peptides displayed strong binding. A similar library of presented peptides was identified when the data was interrogated using the NetMHCpan algorithm. The bioinformatic algorithm presented here demonstrates that there may be a high level of mHA variation in HLA-matched individuals, constituting an HLA-specific alloreactivity potential.

A molecular basis for the presentation of phosphorylated peptides by HLA-B antigens

NARCIS (Netherlands)

Alpízar, Adán; Marino, Fabio; Ramos-Fernández, Antonio; Lombardía, Manuel; Jeko, Anita; Pazos, Florencio; Paradela, Alberto; Santiago, César; Heck, Albert J R; Marcilla, Miguel

2017-01-01

As aberrant protein phosphorylation is a hallmark of tumor cells, the display of tumor-specific phosphopeptides by Human Leukocyte Antigen (HLA) class I molecules can be exploited in the treatment of cancer by T-cell-based immunotherapy. Yet, the characterization and prediction of HLA-I

Structural and regulatory diversity shape HLA-C protein expression levels

DEFF Research Database (Denmark)

Kaur, Gurman; Gras, Stephanie; Mobbs, Jesse I

2017-01-01

expression of HLA-C allomorphs at the cell surface by influencing the structure of the peptide-binding cleft and the diversity of peptides bound by the HLA-C molecules. Together with a phylogenetic analysis, these results highlight the diversity and long-term balancing selection of regulatory factors...

Co-dominant expression of the HLA-G gene and various forms of alternatively spliced HLA-G mRNA in human first trimester trophoblast

DEFF Research Database (Denmark)

Hviid, T V; Møller, C; Sørensen, S

1998-01-01

imprinting of the HLA-G locus could have implications for the interaction in the feto-maternal relationship. Restriction Fragment Length Polymorphism (RFLP), allele-specific amplification and Single Strand Conformation Polymorphism (SSCP) analysis followed by DNA sequencing were performed on Reverse...... Transcription (RT) Polymerase Chain Reaction (PCR) products of HLA-G mRNA to examine the expression of maternal and paternal alleles. Our results demonstrate that HLA-G is co-dominantly expressed in first trimester trophoblast cells. A "new" non-synonymous base substitution in exon 4 was detected. We also...

Evaluation of a competitive enzyme-linked immunosorbent assay for measurements of soluble HLA-G protein.

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Rasmussen, M; Dahl, M; Buus, S; Djurisic, S; Ohlsson, J; Hviid, T V F

2014-08-01

The human leukocyte antigen (HLA) class Ib molecule, HLA-G, has gained increased attention because of its assumed important role in immune regulation. The HLA-G protein exists in several soluble isoforms. Most important are the actively secreted HLA-G5 full-length isoform generated by alternative splicing retaining intron 4 with a premature stop codon, and the cleavage of full-length membrane-bound HLA-G1 from the cell surface, so-called soluble HLA-G1 (sHLA-G1). A specific and sensitive immunoassay for measurements of soluble HLA-G is mandatory for conceivable routine testing and research projects. We report a novel method, a competitive immunoassay, for measuring HLA-G5/sHLA-G1 in biological fluids. The sHLA-G immunoassay is based upon a competitive enzyme-linked immunosorbent assay (ELISA) principle. It includes a recombinant sHLA-G1 protein in complex with β2-microglobulin and a peptide as a standard, biotinylated recombinant sHLA-G1 as an indicator, and the MEM-G/9 anti-HLA-G monoclonal antibody (mAb) as the capture antibody. The specificity and sensitivity of the assay were evaluated. Testing with different recombinant HLA class I proteins and different anti-HLA class I mAbs showed that the sHLA-G immunoassay was highly specific. Optimal combinations of competitor sHLA-G1 and capture mAb concentrations were determined. Two versions of the assay were tested. One with a relatively wide dynamic range from 3.1 to 100.0 ng/ml, and another more sensitive version ranging from 1.6 to 12.5 ng/ml. An intra-assay coefficient of variation (CV) of 15.5% at 88 ng/ml and an inter-assay CV of 23.1% at 39 ng/ml were determined. An assay based on the competitive sHLA-G ELISA may be important for measurements of sHLA-G proteins in several conditions: assisted reproduction, organ transplantation, cancer, and certain pregnancy complications, both in research studies and possibly in the future also for clinical routine use. © 2014 John Wiley & Sons A/S. Published by John Wiley

Measuring Ambiguity in HLA Typing Methods

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Madbouly, Abeer; Freeman, John; Maiers, Martin

2012-01-01

In hematopoietic stem cell transplantation, donor selection is based primarily on matching donor and patient HLA genes. These genes are highly polymorphic and their typing can result in exact allele assignment at each gene (the resolution at which patients and donors are matched), but it can also result in a set of ambiguous assignments, depending on the typing methodology used. To facilitate rapid identification of matched donors, registries employ statistical algorithms to infer HLA alleles from ambiguous genotypes. Linkage disequilibrium information encapsulated in haplotype frequencies is used to facilitate prediction of the most likely haplotype assignment. An HLA typing with less ambiguity produces fewer high-probability haplotypes and a more reliable prediction. We estimated ambiguity for several HLA typing methods across four continental populations using an information theory-based measure, Shannon's entropy. We used allele and haplotype frequencies to calculate entropy for different sets of 1,000 subjects with simulated HLA typing. Using allele frequencies we calculated an average entropy in Caucasians of 1.65 for serology, 1.06 for allele family level, 0.49 for a 2002-era SSO kit, and 0.076 for single-pass SBT. When using haplotype frequencies in entropy calculations, we found average entropies of 0.72 for serology, 0.73 for allele family level, 0.05 for SSO, and 0.002 for single-pass SBT. Application of haplotype frequencies further reduces HLA typing ambiguity. We also estimated expected confirmatory typing mismatch rates for simulated subjects. In a hypothetical registry with all donors typed using the same method, the entropy values based on haplotype frequencies correspond to confirmatory typing mismatch rates of 1.31% for SSO versus only 0.08% for SBT. Intermediate-resolution single-pass SBT contains the least ambiguity of the methods we evaluated and therefore the most certainty in allele prediction. The presented measure objectively evaluates HLA

Measuring ambiguity in HLA typing methods.

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Vanja Paunić

Full Text Available In hematopoietic stem cell transplantation, donor selection is based primarily on matching donor and patient HLA genes. These genes are highly polymorphic and their typing can result in exact allele assignment at each gene (the resolution at which patients and donors are matched, but it can also result in a set of ambiguous assignments, depending on the typing methodology used. To facilitate rapid identification of matched donors, registries employ statistical algorithms to infer HLA alleles from ambiguous genotypes. Linkage disequilibrium information encapsulated in haplotype frequencies is used to facilitate prediction of the most likely haplotype assignment. An HLA typing with less ambiguity produces fewer high-probability haplotypes and a more reliable prediction. We estimated ambiguity for several HLA typing methods across four continental populations using an information theory-based measure, Shannon's entropy. We used allele and haplotype frequencies to calculate entropy for different sets of 1,000 subjects with simulated HLA typing. Using allele frequencies we calculated an average entropy in Caucasians of 1.65 for serology, 1.06 for allele family level, 0.49 for a 2002-era SSO kit, and 0.076 for single-pass SBT. When using haplotype frequencies in entropy calculations, we found average entropies of 0.72 for serology, 0.73 for allele family level, 0.05 for SSO, and 0.002 for single-pass SBT. Application of haplotype frequencies further reduces HLA typing ambiguity. We also estimated expected confirmatory typing mismatch rates for simulated subjects. In a hypothetical registry with all donors typed using the same method, the entropy values based on haplotype frequencies correspond to confirmatory typing mismatch rates of 1.31% for SSO versus only 0.08% for SBT. Intermediate-resolution single-pass SBT contains the least ambiguity of the methods we evaluated and therefore the most certainty in allele prediction. The presented measure

Absence of synergistic enhancement of non-thermal effects of ultrasound on cell killing induced by ionizing radiation

International Nuclear Information System (INIS)

Kondo, T.; Kano, E.

1987-01-01

The present study was performed to elucidate the role of non-thermal effects (cavitation and direct effects) of ultrasound, in simultaneous combination with X-irradiation on the cytotoxicity of mouse L cells. Firstly, mouse L cells were exposed to X-rays and ultrasound (1 MHz continous wave, spatial peak temporal average intensity; 3.7 W/cm 2 ) simultaneously at 37 0 C under O 2 or Ar saturated conditions to examine the cavitational effect of ultrasound. Secondly, cells were exposed to X-rays and ultrasound at 37 0 C under N 2 O saturated conditions, which suppresses the cavitation, to examine the direct effects of ultrasound. The cavitational effect under O 2 and Ar saturated conditions induced an exponential decrease in cell survival, and resulted in an additive effect on cell killing with the combination of X-rays and ultrasound. The direct effect in the N 2 O conditions induced no cell killing and did not modify the cell killing induced by X-rays. These results suggested that the non-thermal effects of ultrasound did not interact synergistically with X-rays for cell killing. (author)

Dynamic range of Nef-mediated evasion of HLA class II-restricted immune responses in early HIV-1 infection.

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Mahiti, Macdonald; Brumme, Zabrina L; Jessen, Heiko; Brockman, Mark A; Ueno, Takamasa

2015-07-31

HLA class II-restricted CD4(+) T lymphocytes play an important role in controlling HIV-1 replication, especially in the acute/early infection stage. But, HIV-1 Nef counteracts this immune response by down-regulating HLA-DR and up-regulating the invariant chain associated with immature HLA-II (Ii). Although functional heterogeneity of various Nef activities, including down-regulation of HLA class I (HLA-I), is well documented, our understanding of Nef-mediated evasion of HLA-II-restricted immune responses during acute/early infection remains limited. Here, we examined the ability of Nef clones from 47 subjects with acute/early progressive infection and 46 subjects with chronic progressive infection to up-regulate Ii and down-regulate HLA-DR and HLA-I from the surface of HIV-infected cells. HLA-I down-regulation function was preserved among acute/early Nef clones, whereas both HLA-DR down-regulation and Ii up-regulation functions displayed relatively broad dynamic ranges. Nef's ability to down-regulate HLA-DR and up-regulate Ii correlated positively at this stage, suggesting they are functionally linked in vivo. Acute/early Nef clones also exhibited higher HLA-DR down-regulation and lower Ii up-regulation functions compared to chronic Nef clones. Taken together, our results support enhanced Nef-mediated HLA class II immune evasion activities in acute/early compared to chronic infection, highlighting the potential importance of these functions following transmission. Copyright © 2015 Elsevier Inc. All rights reserved.

HLA-G mediated immune regulation is impaired by a single amino acid exchange in the alpha 2 domain.

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Celik, Alexander A; Simper, Gwendolin S; Huyton, Trevor; Blasczyk, Rainer; Bade-Döding, Christina

2018-06-01

The trade-off from HLA class I expression to HLA-G expression support the immune evasion of malignant cells. The essential role of the virtually invariant HLA-G in immune tolerance, tumor immunology and its expression frequency in immune privileged tissues is known; however the specific importance of allelic subtypes in immune responses is still not well understood. HLA-G ∗ 01:01, ∗ 01:03 and ∗ 01:04 are the most prevalent allelic variants differing at residues 31 and 110, respectively. In cytotoxicity assays applying K562 cells transduced with the HLA-G variants as targets and NK cells as effectors the differential protective potential of HLA-G variants was analyzed. Their peptide profiles were determined utilizing soluble HLA technology. An increased protective potential of HLA-G ∗ 01:04 could be observed. All variants exhibit a unique peptide repertoire with marginal overlap, while G ∗ 01:04 differs in its peptide anchor profile substantially. The functional differences between HLA-G subtypes could be explained by the constraint of the bound peptides, modifying the pHLA-G accessible surface. For the first time a contribution of amino acid alterations within the HLA-G heavy chain for peptide selection and NK cell recognition could be observed. These results will be a step towards understanding immune tolerance and will guide towards personalized immune therapeutic strategies. Copyright © 2018. Published by Elsevier Inc.

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

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

2015-01-01

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

Expression of the Classical and Nonclassical HLA Molecules in Breast Cancer

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Gisela Bevilacqua Rolfsen Ferreira da Silva

2013-01-01

Full Text Available Considering that downregulation of HLA expression could represent a potential mechanism for breast carcinogenesis and metastasis, the aim of the present study was to use immunohistochemical methods to analyze the expression of HLA-Ia, HLA-DR, HLA-DQ, HLA-E, and HLA-G in invasive ductal carcinoma (IDC of the breast and to relate this HLA profile to anatomopathological parameters. Fifty-two IDC from breast biopsies were stratified according to histological differentiation (well, moderately, and poorly differentiated and to the presence of metastases in axillary lymph nodes. The expression of HLA molecules was assessed by immunohistochemistry, using a computer-assisted system. Overall, 31 (59.6% out of the 52 IDC breast biopsies exhibited high expression of HLA-G, but only 14 (26.9% showed high expression of HLA-E. A large number (41, 78.8% of the biopsies showed low expression of HLA-Ia, while 45 (86.5% showed high expression of HLA-DQ and 36 (69.2% underexpressed HLA-DR. Moreover, 24 (41.2% of 52 biopsies had both low HLA-Ia expression and high HLA-G expression, while 11 (21.2% had low HLA-Ia expression and high HLA-E expression. These results suggest that, by different mechanisms, the downregulation of HLA-Ia, HLA-E, and HLA-DR and the upregulation of HLA-G and HLA-DQ are associated with immune response evasion and breast cancer aggressiveness.

Complement-Mediated Enhancement of Monocyte Adhesion to Endothelial Cells by HLA Antibodies, and Blockade by a Specific Inhibitor of the Classical Complement Cascade, TNT003

Science.gov (United States)

Valenzuela, Nicole M.; Thomas, Kimberly A.; Mulder, Arend; Parry, Graham C.; Panicker, Sandip; Reed, Elaine F.

2017-01-01

Background Antibody-mediated rejection (AMR) of most solid organs is characterized by evidence of complement activation and/or intragraft macrophages (C4d + and CD68+ biopsies). We previously demonstrated that crosslinking of HLA I by antibodies triggered endothelial activation and monocyte adhesion. We hypothesized that activation of the classical complement pathway at the endothelial cell surface by HLA antibodies would enhance monocyte adhesion through soluble split product generation, in parallel with direct endothelial activation downstream of HLA signaling. Methods Primary human aortic endothelial cells (HAEC) were stimulated with HLA class I antibodies in the presence of intact human serum complement. C3a and C5a generation, endothelial P-selectin expression, and adhesion of human primary and immortalized monocytes (Mono Mac 6) were measured. Alternatively, HAEC or monocytes were directly stimulated with purified C3a or C5a. Classical complement activation was inhibited by pretreatment of complement with an anti-C1s antibody (TNT003). Results Treatment of HAEC with HLA antibody and human complement increased the formation of C3a and C5a. Monocyte recruitment by human HLA antibodies was enhanced in the presence of intact human serum complement or purified C3a or C5a. Specific inhibition of the classical complement pathway using TNT003 or C1q-depleted serum significantly reduced adhesion of monocytes in the presence of human complement. Conclusions Despite persistent endothelial viability in the presence of HLA antibodies and complement, upstream complement anaphylatoxin production exacerbates endothelial exocytosis and leukocyte recruitment. Upstream inhibition of classical complement may be therapeutic to dampen mononuclear cell recruitment and endothelial activation characteristic of microvascular inflammation during AMR. PMID:28640789

Vision-Related Quality of Life in Patients with Inactive HLA-B27-Associated-Spectrum Anterior Uveitis.

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Lisette Hoeksema

Full Text Available We investigated the vision-related quality of life (VR-QOL in patients with HLA-B27 associated anterior uveitis (AU. The study was conducted in 2012 at the ophthalmology department of the University Medical Center of Groningen. We included AU patients who were HLA-B27 positive and/or were diagnosed by a rheumatologist with an HLA-B27 associated systemic disease. Sixty-one of 123 (50% adult patients participated. All patients filled-out the National Eye Institute Visual Functioning Questionnaire-25 (NEI VFQ-25, Beck Depression Inventory (BDI-II, social support lists and an additional questionnaire for gathering general information. Medical records were reviewed for clinical characteristics. Analyses were conducted on various patient and ocular characteristics. We compared our NEI VFQ-25 scores with those previously found in the literature. Our main outcome measures were VR-QOL scores and their associations with various general patient and ocular characteristics. We found that the NEI VFQ-25 mean overall composite score was 88.9±8.8, which is relatively high, but lower than that found in a normal working population. The mean general health score was 47.4±20.8, which is lower than in patients with other ocular diseases. Patients with a systemic disease scored significantly lower on general health and VR-QOL, compared to patients without a systemic disease. Patients with a depression (6/59 (10% frequently had ankylosing spondylitis (5/6 patients and they scored significantly worse on VR-QOL. We concluded that patients with HLA-B27 associated AU have a relatively high VR-QOL. However, the presence of a systemic disease is associated with lower VR-QOL and general health scores. In addition, depression is associated with a lower VR-QOL.

Hydrodynamic cavitation kills prostate cells and ablates benign prostatic hyperplasia tissue.

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Itah, Zeynep; Oral, Ozlem; Perk, Osman Yavuz; Sesen, Muhsincan; Demir, Ebru; Erbil, Secil; Dogan-Ekici, A Isin; Ekici, Sinan; Kosar, Ali; Gozuacik, Devrim

2013-11-01

Hydrodynamic cavitation is a physical phenomenon characterized by vaporization and bubble formation in liquids under low local pressures, and their implosion following their release to a higher pressure environment. Collapse of the bubbles releases high energy and may cause damage to exposed surfaces. We recently designed a set-up to exploit the destructive nature of hydrodynamic cavitation for biomedical purposes. We have previously shown that hydrodynamic cavitation could kill leukemia cells and erode kidney stones. In this study, we analyzed the effects of cavitation on prostate cells and benign prostatic hyperplasia (BPH) tissue. We showed that hydrodynamic cavitation could kill prostate cells in a pressure- and time-dependent manner. Cavitation did not lead to programmed cell death, i.e. classical apoptosis or autophagy activation. Following the application of cavitation, we observed no prominent DNA damage and cells did not arrest in the cell cycle. Hence, we concluded that cavitation forces directly damaged the cells, leading to their pulverization. Upon application to BPH tissues from patients, cavitation could lead to a significant level of tissue destruction. Therefore similar to ultrasonic cavitation, we propose that hydrodynamic cavitation has the potential to be exploited and developed as an approach for the ablation of aberrant pathological tissues, including BPH.

Association study between HLA-DRB, HLA-DQA1, HLA-DQB1 and breast cancer in Iranian women

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Amirzargar AA

2010-11-01

Full Text Available "n Normal 0 false false false EN-US X-NONE AR-SA MicrosoftInternetExplorer4 /* Style Definitions */ table.MsoNormalTable {mso-style-name:"Table Normal"; mso-tstyle-rowband-size:0; mso-tstyle-colband-size:0; mso-style-noshow:yes; mso-style-priority:99; mso-style-qformat:yes; mso-style-parent:""; mso-padding-alt:0in 5.4pt 0in 5.4pt; mso-para-margin:0in; mso-para-margin-bottom:.0001pt; mso-pagination:widow-orphan; font-size:11.0pt; font-family:"Calibri","sans-serif"; mso-ascii-font-family:Calibri; mso-ascii-theme-font:minor-latin; mso-fareast-font-family:"Times New Roman"; mso-fareast-theme-font:minor-fareast; mso-hansi-font-family:Calibri; mso-hansi-theme-font:minor-latin; mso-bidi-font-family:Arial; mso-bidi-theme-font:minor-bidi;} Background: Based on the reports, high frequency of special alleles of HLA class II genes might be associated with susceptibility to or protective from a particular cancer. These alleles might vary depending on the geographical region. Here we investigate the association between alleles of HLA class II genes and breast cancer in Iranian women."n"nMethods: 100 patients with pathologically proved breast cancer who referred to Cancer Institute, Tehran University of Medical Sciences in Tehran, Iran, were divided to two groups based on ages (40 years old and less/ or more than 40 years old and were randomly selected and compared with a group of 80 healthy blood donor subjects. HLA class II alleles were determined by amplification of DNA with polymerase chain reaction (PCR method followed by HLA-typing using sequence-specific primer (SSP for each allele."n"nResults: The most frequent alleles in the DR and DQ regions in group 1 (40 years old and less in comparison with control group were HLA-DQA1*0301 (p=0.002 and HLA-DQB1*0302 (p>0.05. In contrast HLA-DQA1*0505 (p=0.004 had significantly lower frequency in this group compared with control group. Patients of group two (more than 40 years old had a higher frequencies of HLA

Chimerism and tolerance without GVHD or engraftment syndrome in HLA-mismatched combined kidney and hematopoietic stem cell transplantation.

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Leventhal, Joseph; Abecassis, Michael; Miller, Joshua; Gallon, Lorenzo; Ravindra, Kadiyala; Tollerud, David J; King, Bradley; Elliott, Mary Jane; Herzig, Geoffrey; Herzig, Roger; Ildstad, Suzanne T

2012-03-07

The toxicity of chronic immunosuppressive agents required for organ transplant maintenance has prompted investigators to pursue approaches to induce immune tolerance. We developed an approach using a bioengineered mobilized cellular product enriched for hematopoietic stem cells (HSCs) and tolerogenic graft facilitating cells (FCs) combined with nonmyeloablative conditioning; this approach resulted in engraftment, durable chimerism, and tolerance induction in recipients with highly mismatched related and unrelated donors. Eight recipients of human leukocyte antigen (HLA)-mismatched kidney and FC/HSC transplants underwent conditioning with fludarabine, 200-centigray total body irradiation, and cyclophosphamide followed by posttransplant immunosuppression with tacrolimus and mycophenolate mofetil. Subjects ranged in age from 29 to 56 years. HLA match ranged from five of six loci with related donors to one of six loci with unrelated donors. The absolute neutrophil counts reached a nadir about 1 week after transplant, with recovery by 2 weeks. Multilineage chimerism at 1 month ranged from 6 to 100%. The conditioning was well tolerated, with outpatient management after postoperative day 2. Two subjects exhibited transient chimerism and were maintained on low-dose tacrolimus monotherapy. One subject developed viral sepsis 2 months after transplant and experienced renal artery thrombosis. Five subjects experienced durable chimerism, demonstrated immunocompetence and donor-specific tolerance by in vitro proliferative assays, and were successfully weaned off all immunosuppression 1 year after transplant. None of the recipients produced anti-donor antibody or exhibited engraftment syndrome or graft-versus-host disease. These results suggest that manipulation of a mobilized stem cell graft and nonmyeloablative conditioning represents a safe, practical, and reproducible means of inducing durable chimerism and donor-specific tolerance in solid organ transplant recipients.

Combining Vγ9Vδ2 T Cells with a Lipophilic Bisphosphonate Efficiently Kills Activated Hepatic Stellate Cells

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Xiaoying Zhou

2017-10-01

Full Text Available Activated hepatic stellate cells (aHSCs are now established as a central driver of fibrosis in human liver injury. In the presence of chronic or repeated injury, fibrosis, cirrhosis, and hepatocellular carcinoma (HCC can occur, so there is interest in down-regulating aHSCs activity in order to treat these diseases. Here, we report that Vγ9Vδ2 T cells are reduced in patients with liver cirrhosis, stimulating us to investigate possible interactions between Vγ9Vδ2 T cells and aHSCs. We find that Vγ9Vδ2 T cells kill aHSCs and killing is enhanced when aHSCs are pretreated with BPH-1236, a lipophilic analog of the bone resorption drug zoledronate. Cytotoxicity is mediated by direct cell-to-cell contact as shown by Transwell experiments and atomic force microscopy, with BPH-1236 increasing the adhesion between aHSCs and Vγ9Vδ2 T cells. Mechanistically, BPH-1236 functions by inhibiting farnesyl diphosphate synthase, leading to accumulation of the phosphoantigen isopentenyl diphosphate and recognition by Vγ9Vδ2 T cells. The cytolytic process is largely dependent on the perforin/granzyme B pathway. In a Rag2−/−γc−/− immune-deficient mouse model, we find that Vγ9Vδ2 T cells home-in to the liver, and when accompanied by BPH-1236, kill not only orthotopic aHSCs but also orthotopic HCC tumors. Collectively, our results provide the first proof-of-concept of a novel immunotherapeutic strategy for the treatment of fibrosis–cirrhosis–HCC diseases using adoptively transferred Vγ9Vδ2 T cells, combined with a lipophilic bisphosphonate.

Identification and HLA-tetramer-validation of human CD4+ and CD8+ T cell responses against HCMV proteins IE1 and IE2.

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Braendstrup, Peter; Mortensen, Bo Kok; Justesen, Sune; Osterby, Thomas; Rasmussen, Michael; Hansen, Andreas Martin; Christiansen, Claus Bohn; Hansen, Morten Bagge; Nielsen, Morten; Vindeløv, Lars; Buus, Søren; Stryhn, Anette

2014-01-01

Human cytomegalovirus (HCMV) is an important human pathogen. It is a leading cause of congenital infection and a leading infectious threat to recipients of solid organ transplants as well as of allogeneic hematopoietic cell transplants. Moreover, it has recently been suggested that HCMV may promote tumor development. Both CD4+ and CD8+ T cell responses are important for long-term control of the virus, and adoptive transfer of HCMV-specific T cells has led to protection from reactivation and HCMV disease. Identification of HCMV-specific T cell epitopes has primarily focused on CD8+ T cell responses against the pp65 phosphoprotein. In this study, we have focused on CD4+ and CD8+ T cell responses against the immediate early 1 and 2 proteins (IE1 and IE2). Using overlapping peptides spanning the entire IE1 and IE2 sequences, peripheral blood mononuclear cells from 16 healthy, HLA-typed, donors were screened by ex vivo IFN-γ ELISpot and in vitro intracellular cytokine secretion assays. The specificities of CD4+ and CD8+ T cell responses were identified and validated by HLA class II and I tetramers, respectively. Eighty-one CD4+ and 44 CD8+ T cell responses were identified representing at least seven different CD4 epitopes and 14 CD8 epitopes restricted by seven and 11 different HLA class II and I molecules, respectively, in total covering 91 and 98% of the Caucasian population, respectively. Presented in the context of several different HLA class II molecules, two epitope areas in IE1 and IE2 were recognized in about half of the analyzed donors. These data may be used to design a versatile anti-HCMV vaccine and/or immunotherapy strategy.

Identification and HLA-tetramer-validation of human CD4+ and CD8+ T cell responses against HCMV proteins IE1 and IE2.

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Peter Braendstrup

Full Text Available Human cytomegalovirus (HCMV is an important human pathogen. It is a leading cause of congenital infection and a leading infectious threat to recipients of solid organ transplants as well as of allogeneic hematopoietic cell transplants. Moreover, it has recently been suggested that HCMV may promote tumor development. Both CD4+ and CD8+ T cell responses are important for long-term control of the virus, and adoptive transfer of HCMV-specific T cells has led to protection from reactivation and HCMV disease. Identification of HCMV-specific T cell epitopes has primarily focused on CD8+ T cell responses against the pp65 phosphoprotein. In this study, we have focused on CD4+ and CD8+ T cell responses against the immediate early 1 and 2 proteins (IE1 and IE2. Using overlapping peptides spanning the entire IE1 and IE2 sequences, peripheral blood mononuclear cells from 16 healthy, HLA-typed, donors were screened by ex vivo IFN-γ ELISpot and in vitro intracellular cytokine secretion assays. The specificities of CD4+ and CD8+ T cell responses were identified and validated by HLA class II and I tetramers, respectively. Eighty-one CD4+ and 44 CD8+ T cell responses were identified representing at least seven different CD4 epitopes and 14 CD8 epitopes restricted by seven and 11 different HLA class II and I molecules, respectively, in total covering 91 and 98% of the Caucasian population, respectively. Presented in the context of several different HLA class II molecules, two epitope areas in IE1 and IE2 were recognized in about half of the analyzed donors. These data may be used to design a versatile anti-HCMV vaccine and/or immunotherapy strategy.

A highly restricted T-cell receptor dominates the CD8+ T-cell response to parvovirus B19 infection in HLA-A*2402-positive individuals

DEFF Research Database (Denmark)

Kasprowicz, V; Isa, Adiba; Jeffery, K

2006-01-01

Six of seven HLA-A*2402-positive individuals with acute parvovirus B19 infections made vigorous CD8-positive cytotoxic T-cell (CTL) responses to the viral epitope FYTPLADQF. All responders showed highly focused T-cell receptor (TCR) usage, using almost exclusively BV5.1. The BV5.1 TCR dominated...

An Anti-C1s Monoclonal, TNT003, Inhibits Complement Activation Induced by Antibodies Against HLA.

Science.gov (United States)

Thomas, K A; Valenzuela, N M; Gjertson, D; Mulder, A; Fishbein, M C; Parry, G C; Panicker, S; Reed, E F

2015-08-01

Antibody-mediated rejection (AMR) of solid organ transplants (SOT) is characterized by damage triggered by donor-specific antibodies (DSA) binding donor Class I and II HLA (HLA-I and HLA-II) expressed on endothelial cells. While F(ab')2 portions of DSA cause cellular activation and proliferation, Fc regions activate the classical complement cascade, resulting in complement deposition and leukocyte recruitment, both hallmark features of AMR. We characterized the ability of an anti-C1s monoclonal antibody, TNT003, to inhibit HLA antibody (HLA-Ab)-induced complement activation. Complement deposition induced by HLA-Ab was evaluated using novel cell- and bead-based assays. Human aortic endothelial cells (HAEC) were cultured with HLA-Ab and human complement; production of activated complement proteins was measured by flow cytometry. Additionally, C3d deposition was measured on single antigen beads (SAB) mixed with HLA-Ab and human complement. TNT003 inhibited HLA-Ab mediated complement deposition on HAEC in a concentration-dependent manner; C3a, C4a and C5a anaphylatoxin production was also diminished by TNT003. Finally, TNT003 blocked C3d deposition induced by Class I (HLAI-Ab)- and Class II (HLAII-Ab)-specific antibodies on SAB. These data suggest TNT003 may be useful for modulating the effects of DSA, as TNT003 inhibits complement deposition and split product formation generated by HLA-I/II-Ab in vitro. © 2015 The Authors. American Journal of Transplantation Published by Wiley Periodicals, Inc.

Characterization of a Proteasome and TAP-independent Presentation of Intracellular Epitopes by HLA-B27 Molecules

KAUST Repository

Magnacca, A.

2012-07-17

Nascent HLA-class I molecules are stabilized by proteasome-derived peptides in the ER and the new complexes proceed to the cell surface through the post-ER vesicles. It has been shown, however, that less stable complexes can exchange peptides in the Trans Golgi Network (TGN). HLA-B27 are the most studied HLA-class I molecules due to their association with Ankylosing Spondylitis (AS). Chimeric proteins driven by TAT of HIV have been exploited by us to deliver viral epitopes, whose cross-presentation by the HLA-B27 molecules was proteasome and TAP-independent and not restricted to Antigen-Presenting Cells (APC). Here, using these chimeric proteins as epitope suppliers, we compared with each other and with the HLA-A2 molecules, the two HLA-B*2705 and B*2709 alleles differing at residue 116 (D116H) and differentially associated with AS. We found that the antigen presentation by the two HLA-B27 molecules was proteasome-, TAP-, and APC-independent whereas the presentation by the HLA-A2 molecules required proteasome, TAP and professional APC. Assuming that such difference could be due to the unpaired, highly reactive Cys-67 distinguishing the HLA-B27 molecules, C67S mutants in HLA-B*2705 and B*2709 and V67C mutant in HLA-A*0201 were also analyzed. The results showed that this mutation did not influence the HLA-A2-restricted antigen presentation while it drastically affected the HLA-B27-restricted presentation with, however, remarkable differences between B*2705 and B*2709. The data, together with the occurrence on the cell surface of unfolded molecules in the case of C67S-B*2705 mutant but not in that of C67S-B*2709 mutant, indicates that Cys-67 has a more critical role in stabilizing the B*2705 rather than the B*2709 complexes.

Strong synergy of heat and modulated electromagnetic field in tumor cell killing.

Science.gov (United States)

Andocs, Gabor; Renner, Helmut; Balogh, Lajos; Fonyad, Laszlo; Jakab, Csaba; Szasz, Andras

2009-02-01

Hyperthermia is an emerging complementary method in radiooncology. Despite many positive studies and comprehensive reviews, the method is not widely accepted as a combination to radiotherapy. Modulated electrohyperthermia (mEHT; capacitive, electric field modulated, 13.56 MHz) has been used in clinical practice for almost 2 decades in Germany, Austria and Hungary. This in vivo study in nude mice xenograft tumors compares mEHT with "classic" radiative hyperthermia (radHT). Nude mice were xenografted with HT29 human colorectal carcinoma cells. 28 mice in four groups with seven animals each and two tumors per animal (totally 56 tumors) were included in the present study: group 1 as untreated control; group 2 treated with radHT at 42 degrees C; group 3 treated with mEHT at identical 42 degrees C; group 4 treated with mEHT at 38 degrees C (by intensively cooling down the tumor). 24 h after treatment, animals were sacrificed and the tumor cross sections studied by precise morphological methods for the respective relative amount of "dead" tumor cells. The effect of mEHT established a double effect as a synergy between the purely thermal (temperature-dependent) and nonthermal (not directly temperature-dependent) effects. The solely thermal enhancement ratio (TER) of cell killing was shown to be 2.9. The field enhancement ratio (FER) at a constant temperature of 42 degrees C was measured as 3.2. Their complex application significantly increased the therapeutic enhancement to 9.4. mEHT had a remarkable cancer cell-killing effect in a nude mice xenograft model.

Strong synergy of heat and modulated electromagnetic field in tumor cell killing

International Nuclear Information System (INIS)

Andocs, Gabor; Fonyad, Laszlo; Jakab, Csaba; Szasz, Andras

2009-01-01

Hyperthermia is an emerging complementary method in radiooncology. Despite many positive studies and comprehensive reviews, the method is not widely accepted as a combination to radiotherapy. Modulated electrohyperthermia (mEHT; capacitive, electric field modulated, 13.56 MHz) has been used in clinical practice for almost 2 decades in Germany, Austria and Hungary. This in vivo study in nude mice xenograft tumors compares mEHT with ''classic'' radiative hyperthermia (radHT). Nude mice were xenografted with HT29 human colorectal carcinoma cells. 28 mice in four groups with seven animals each and two tumors per animal (totally 56 tumors) were included in the present study: group 1 as untreated control; group 2 treated with radHT at 42 C; group 3 treated with mEHT at identical 42 C; group 4 treated with mEHT at 38 C (by intensively cooling down the tumor). 24 h after treatment, animals were sacrificed and the tumor cross sections studied by precise morphological methods for the respective relative amount of ''dead'' tumor cells. The effect of mEHT established a double effect as a synergy between the purely thermal (temperature-dependent) and nonthermal (not directly temperature-dependent) effects. The solely thermal enhancement ratio (TER) of cell killing was shown to be 2.9. The field enhancement ratio (FER) at a constant temperature of 42 C was measured as 3.2. Their complex application significantly increased the therapeutic enhancement to 9.4. mEHT had a remarkable cancer cell-killing effect in a nude mice xenograft model. (orig.)

Strong synergy of heat and modulated electromagnetic field in tumor cell killing

Energy Technology Data Exchange (ETDEWEB)

Andocs, Gabor [Frederic Joliot Curie National Research Inst. for Radiobiology and Radiohygiene, Budapest (Hungary)]|[St. Istvan Univ., Budapest (Hungary). Dept. of Pharmacology and Toxicology; Renner, Helmut [Klinikum Nuernberg (Germany). Clinic of Radiooncology; Balogh, Lajos [Frederic Joliot Curie National Research Inst. for Radiobiology and Radiohygiene, Budapest (Hungary); Fonyad, Laszlo [Semmelweis Univ., Budapest (Hungary). 1. Dept. of of Pathology and Experimental Cancer Research; Jakab, Csaba [St. Istvan Univ., Budapest (Hungary). Dept. of Pathology; Szasz, Andras [St. Istvan Univ., Goedoelloe (Hungary). Biotechnics Dept.

2009-02-15

Hyperthermia is an emerging complementary method in radiooncology. Despite many positive studies and comprehensive reviews, the method is not widely accepted as a combination to radiotherapy. Modulated electrohyperthermia (mEHT; capacitive, electric field modulated, 13.56 MHz) has been used in clinical practice for almost 2 decades in Germany, Austria and Hungary. This in vivo study in nude mice xenograft tumors compares mEHT with 'classic' radiative hyperthermia (radHT). Nude mice were xenografted with HT29 human colorectal carcinoma cells. 28 mice in four groups with seven animals each and two tumors per animal (totally 56 tumors) were included in the present study: group 1 as untreated control; group 2 treated with radHT at 42 C; group 3 treated with mEHT at identical 42 C; group 4 treated with mEHT at 38 C (by intensively cooling down the tumor). 24 h after treatment, animals were sacrificed and the tumor cross sections studied by precise morphological methods for the respective relative amount of 'dead' tumor cells. The effect of mEHT established a double effect as a synergy between the purely thermal (temperature-dependent) and nonthermal (not directly temperature-dependent) effects. The solely thermal enhancement ratio (TER) of cell killing was shown to be 2.9. The field enhancement ratio (FER) at a constant temperature of 42 C was measured as 3.2. Their complex application significantly increased the therapeutic enhancement to 9.4. mEHT had a remarkable cancer cell-killing effect in a nude mice xenograft model. (orig.)

Successful renal transplantation across HLA barrier: Report from India

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G Aggarwal

2017-01-01

Full Text Available Organ donors are sometimes found “unsuitable” due to the presence of donor-specific anti-HLA antibodies in the recipient. In recent years, improved desensitization protocols have successfully helped to overcome HLA incompatibility hurdle. We present three cases where optimum desensitization was achieved in patients with the donor-specific anti-HLA antibody (DSA leading to successful renal transplantation. All patient–donor pair underwent HLA typing, complement dependent cytotoxicity crossmatch (CDC-XM, flow cytometry XM (FC-XM, and panel reactive antibody. If any of the three tests was positive, single antigen bead assay was performed to determine the specificity of the anti-HLA antibody (s. Patients with DSA were offered organ-swap or anti-HLA antibody desensitization followed by transplantation. Desensitization protocol consisted of single dose rituximab and cascade plasmapheresis (CP along with standard triple immunosuppression. The target DSA mean fluorescence index (MFI was <500, along with negative CDC-XM and FC-XM for both T- and B-cells. Three patients with anti-HLA DSA, who did not find a suitable match in organ swap program, consented to anti-HLA antibody desensitization, followed by transplantation. Mean pre-desensitization antibody MFI was 1740 (1422–2280. Mean number of CP required to achieve the target MFI was 2.3 (2–3. All the three patients are on regular follow-up and have normal renal function test at a mean follow-up of 8 months. This report underlines successful application of desensitization protocol leading to successful HLA-antibody incompatible renal transplants and their continued normal renal functions.