scholarly journals 10.02 Genomic HLA homozygosity is frequent in esophageal adenocarcinoma and related to low immunogenicity

2021 ◽  
Vol 9 (Suppl 1) ◽  
pp. A1.2-A2
Author(s):  
MA Garcia-Marquez ◽  
M Thelen ◽  
E Bauer ◽  
K Wennhold ◽  
J Lehmann ◽  
...  
Keyword(s):  
T Cells ◽  
Expert Witness ◽  
Germ Line ◽  
Cytotoxic T Cells ◽  
Rna Extraction ◽  
Immune Surveillance ◽  
Human Leukocyte ◽  
Normal Peripheral Blood ◽  
Synonymous Mutations ◽  
Hla Class I Molecules

BackgroundClassical human leukocyte antigen (HLA) class I molecules are expressed by most somatic cells and present peptides to cytotoxic T cells. The HLA-genotype of an individual contains up to six different HLA-I molecules and defines the repertoire of peptides that can be presented to cytotoxic T cells. Homozygosity for one or more HLA-loci could translate in a smaller repertoire of tumour neoantigens possibly presented to cytotoxic T cells in an individual and potentially predispose such individuals with a disadvantage to fight a nascent tumour.Material and MethodsHigh-resolution HLA-genotyping from germline normal DNA of 80 esophago-gastric adenocarcinoma (EGA) patients was performed with the NGS method by Illumina. Whole exome sequencing (WES) was performed on tumor tissue and normal peripheral blood cells (n=39). The data were processed, and non-synonymous mutations were called. The amount of potential high-affinity binders derived from 10 cancer testis antigens (CTAs) frequently expressed in EGA and non-synonymous mutations obtained from WES data were determined using an in-silico approach for MHC-binding (IEDB.org). RNA-extraction and gene expression profiling were performed using the NanoString technology.ResultsWe compared the frequency of HLA homozygosity in EGA patients to an HLA-matched reference population derived from a large cohort of bone marrow donors (n=7.615 out of 615.017 donors). We demonstrate that EGA patients are more likely to be homozygous for at least one HLA-I gene than the control population. In EGA patients, 35% of HLA-A, -B, and -C alleles were homozygous in comparison with 19% of HLA alleles among the HLA-matched general population. This difference corresponded to an odds ratio (OR) for homozygosity of 2.282 (95% confidence interval (CI) 1.442-3.615, p<0.001). The odds ratios for homozygosity at HLA-A (OR=1.885, CI=1.111-3.236, p<0.05), HLA-B (OR=3.045, CI=1.346-6.499, p<0.05) and HLA-C (OR=2.170, CI=1.445-3.579, p<0.05) were significantly different. We then aimed to estimate the influence of HLA-homozygosity in the context of tumour immune surveillance. Predictions by IEDB analysis resource tool indeed showed a reduced repertoire of high and moderate-affinity MHC-binders (both CTA-derived and mutation-derived peptides) in the homozygous cohort. Our findings demonstrate a reduced amount of potentially immunogenic peptides in EGA patients with HLA-homozygosity for at least one locus, which may result in impaired cancer immunosurveillance. In line with this observation, we also found increased levels of CTA expression in homozygous compared to heterozygous patients. After artificial modification of the genotype of homozygous patients to a heterozygous genotype, the set of predicted good-binding peptides was comparable to the heterozygous cohort.ConclusionOur results highlight the effect of HLA-I homozygosity on the immunopeptidome as important prerequisite of anti-tumor immunity. The high frequency of genomic HLA-I homozygosity observed in the EGA cohort may reflect an increased cancer risk for these patients. Together with previous reports demonstrating reduced survival after checkpoint therapy, our study suggests consideration of germ-line HLA-homozygosity for the design and interpretation of immunotherapeutic trials.Disclosure InformationM.A. Garcia-Marquez: None. M. Thelen: None. E. Bauer: None. K. Wennhold: None. J. Lehmann: None. D. Keller: None. B. Gathof: None. L. Maas: None. J. George: None. C. Bruns: None. A. Quaas: None. M. von Bergwelt-Baildon: C. Other Research Support (supplies, equipment, receipt of drugs or other in-kind support); Modest; Astellas, Roche, MSD. D. Speakers Bureau/Honoraria (speakers bureau, symposia, and expert witness); Modest; BMS. M. Peifer: None. H.A. Schlößer: B. Research Grant (principal investigator, collaborator or consultant and pending grants as well as grants already received); Significant; Astra Zeneca. D. Speakers Bureau/Honoraria (speakers bureau, symposia, and expert witness); Modest; BMS.

Cord blood comprises antigen-experienced T cells specific for maternal minor histocompatibility antigen HA-1

Blood ◽  
2005 ◽  
Vol 105 (4) ◽  
pp. 1823-1827 ◽  
Author(s):  
Bregje Mommaas ◽  
Janine A. Stegehuis-Kamp ◽  
Astrid G. van Halteren ◽  
Michel Kester ◽  
Jürgen Enczmann ◽  
...  
Keyword(s):  
T Cells ◽  
Cord Blood ◽  
Ex Vivo ◽  
Cytotoxic T Cells ◽  
Cord Blood Transplantation ◽  
Human Leukocyte ◽  
Leukemic Cells ◽  
Target Cells ◽  
Graft Versus Leukemia

AbstractUmbilical cord blood transplantation is applied as treatment for mainly pediatric patients with hematologic malignancies. The clinical results show a relatively low incidence of graft-versus-host disease and leukemia relapse. Since maternal cells traffic into the fetus during pregnancy, we questioned whether cord blood has the potential to generate cytotoxic T cells specific for the hematopoietic minor histocompatibility (H) antigen HA-1 that would support the graft-versus-leukemia effect. Here, we demonstrate the feasibility of ex vivo generation of minor H antigen HA-1-specific T cells from cord blood cells. Moreover, we observed pre-existing HA-1-specific T cells in cord blood samples. Both the circulating and the ex vivo-generated HA-1-specific T cells show specific and hematopoietic restricted lysis of human leukocyte antigen-A2pos/HA-1pos (HLA-A2pos/HA-1pos) target cells, including leukemic cells. The cord blood-derived HA-1-specific cytotoxic T cells are from child origin. Thus, the so-called naive cord blood can comprise cytotoxic T cells directed at the maternal minor H antigen HA-1. The apparent immunization status of cord blood may well contribute to the in vivo graft-versus-leukemia activity after transplantation. Moreover, since the fetus cannot be primed against Y chromosome-encoded minor H antigens, cord blood is an attractive stem cell source for male patients. (Blood. 2005;105:1823-1827)

scholarly journals Preclinical and clinical development of therapeutic antibodies targeting functions of CD47 in the tumor microenvironment

2020 ◽  
Vol 3 (3) ◽  
pp. 179-192
Author(s):  
Sukhbir Kaur ◽  
Kyle V Cicalese ◽  
Rajdeep Banerjee ◽  
David D Roberts
Keyword(s):  
T Cells ◽  
Tumor Microenvironment ◽  
Cytotoxic T Cells ◽  
Regulatory Protein ◽  
Immune Surveillance ◽  
Hematologic Malignancies ◽  
Clinical Development ◽  
Surface Glycoprotein ◽  
Cell Surface Glycoprotein ◽  
Thrombospondin 1

ABSTRACT CD47 is a ubiquitously expressed cell surface glycoprotein that functions as a signaling receptor for thrombospondin-1 and as the counter-receptor for signal regulatory protein-α (SIRPα). Engaging SIRPα on macrophages inhibits phagocytosis, and CD47 thereby serves as a physiological marker of self. However, elevated CD47 expression on some cancer cells also protects tumors from innate immune surveillance and limits adaptive antitumor immunity via inhibitory SIRPα signaling in antigen-presenting cells. CD47 also mediates inhibitory thrombospondin-1 signaling in vascular cells, T cells, and NK cells, and blocking inhibitory CD47 signaling on cytotoxic T cells directly increases tumor cell killing. Therefore, CD47 functions as an innate and adaptive immune checkpoint. These findings have led to the development of antibodies and other therapeutic approaches to block CD47 functions in the tumor microenvironment. Preclinical studies in mice demonstrated that blocking CD47 can limit the growth of hematologic malignancies and solid tumors and enhance the efficacy of conventional chemotherapy, radiation therapy, and some targeted cancer therapies. Humanized CD47 antibodies are showing promise in early clinical trials, but side effects related to enhanced phagocytic clearance of circulating blood cells remain a concern. Approaches to circumvent these include antibody preloading strategies and development of antibodies that recognize tumor-specific epitopes of CD47, SIRPα antibodies, and bivalent antibodies that restrict CD47 blockade to specific tumor cells. Preclinical and clinical development of antibodies and related biologics that inhibit CD47/SIRPα signaling are reviewed, including strategies to combine these agents with various conventional and targeted therapeutics to improve patient outcome for various cancers.

scholarly journals Cholangiocarcinoma with respect to IgG4 Reaction

2014 ◽  
Vol 2014 ◽  
pp. 1-8 ◽  
Author(s):  
Kenichi Harada ◽  
Yasuni Nakanuma
Keyword(s):  
T Cells ◽  
Plasma Cells ◽  
Cytotoxic T Cells ◽  
Immune Surveillance ◽  
Intraepithelial Neoplasia ◽  
Cell Switching ◽  
Igg4 Related Disease ◽  
Regulatory Cytokine ◽  
High Risk Factor ◽  
Antigen Presenting

IgG4 reactions marked by infiltration of IgG4-positive plasma cells in affected organs occur in cancer patients and in patients with IgG4-related diseases. Extrahepatic cholangiocarcinomas including gall bladder cancer are often accompanied by significant IgG4 reactions; these reactions show a negative correlation with CD8-positive cytotoxic T cells, suggesting that the evasion of immune surveillance is associated with cytotoxic T cells. The regulatory cytokine IL-10 may induce IgG4-positive plasma cell differentiation or promote B cell switching to IgG4 in the presence of IL-4. Cholangiocarcinoma cells may function as nonprofessional antigen presenting cells that indirectly induce IgG4 reactions via the IL-10-producing cells and/or these may act as Foxp3-positive and IL-10-producing cells that directly induce IgG4 reactions. Moreover, IgG4-related disease is a high-risk factor for cancer development; IgG4-related sclerosing cholangitis (IgG4-SC) cases associated with cholangiocarcinoma or its precursor lesion biliary intraepithelial neoplasia (BilIN) have been reported. IgG4-positive cell infiltration is an important finding of IgG4-SC but is not a histological hallmark of IgG4-SC. For the diagnosis of IgG4-SC, its differentiation from cholangiocarcinoma remains important.

Rag1 Deficiency Does Not Affect Myelodysplasia but Leads to More Rapid Leukemic Transformation in a Mouse Model of MDS.

Blood ◽  
2009 ◽  
Vol 114 (22) ◽  
pp. 2784-2784
Author(s):  
Sheryl M Gough ◽  
Yang Jo Chung ◽  
Peter D. Aplan
Keyword(s):  
Bone Marrow ◽  
T Cells ◽  
Peripheral Blood ◽  
Cytotoxic T Cells ◽  
Immune Surveillance ◽  
Severe Anemia ◽  
Control Groups ◽  
Leukemic Transformation ◽  
Significant Difference

Abstract Abstract 2784 Poster Board II-760 MDS comprises a premalignant heterogeneous group of clonal stem cell disorders that also show bone marrow dysplasia and which often evolve to acute myeloid leukemia (AML). Aplastic anemia (AA) patients also share the bone marrow failure, anemia and resulting peripheral blood cytopenias of MDS. AA is thought to be caused by an oligoclonal expansion of cytotoxic T-cells that target haematopoietic stem and progenitor cells. The severe anemia and leucopenia characteristic of both diseases is relieved in AA patients and some MDS patients by immunosuppressive therapy, supporting the role of cytotoxic T-cells in the etiology of AA. However, the role of the lymphocytes in progressive MDS remains unclear. MDS has been associated with a number of genetic aberrations, including chromosomal translocations involving the NUP98 gene. Using mice that express a NUP98-HOXD13 (NHD13) transgene, previously shown to manifest the same clinical symptoms as those of MDS patients, we have followed a cohort of NHD13/Rag1−/− mice to determine if the absence of lymphocytes, especially T cells, might 1) diminish the severity of the MDS, or 2) effect transformation and/or survival in the NHD13 mice, as would be predicted by an “immune surveillance” hypothesis of malignant transformation. Serial CBCs at two month time intervals were used to evaluate the extent of anemia and leucopenia in NHD13+ /Rag1+/+ and NHD13/Rag1−/−, as well as WT/Rag1+/− and WT/Rag1−/− control groups over a 15 month period. NHD13/Rag1−/− mice were generated by crossing the NHD13+ (C57BL/6) with the B6;129S7-Rag1tm1Mom/J mouse, and housed in a Specific Pathogen-Free (SPF) environment. Mice were euthanized and analyzed when CBCs indicated severe anemia/leucopenia or leukemic transformation, or when determined to be unwell (hunched, immobile, dyspnea) by observation. Flow cytometry, histology and genomic analyses further determined leukemia subtype, extent of infiltration and leukemia clonality. NHD13+ /Rag1+/+ and NHD13/Rag1−/− mice showed no significant differences at any two month time-point in hemoglobin (Hg), mean corpuscular volume (MCV), or platelet levels, and progressive MDS occurred in both groups. Consistent with previous studies, and excluding cases that showed evident transformation to acute leukemia, NHD13+ /Rag1+/+ mice showed low WBC, neutrophil and lymphocyte numbers, which were not significantly different from the NHD13/Rag1−/− mice. NHD13/Rag1−/− mice did however show a significantly reduced survival when compared with the NHD13+ /Rag1+/+ mice (Log-rank test, p = 0.0135), and survival medians of 11 and 13 months, respectively. Incidence of leukemic transformation was increased in the NHD13/Rag1−/− compared with the NHD13+ /Rag1+/+ mice (p=0.0079). A range of leukemia subtypes was observed in both the NHD13+ /Rag1+/+ and NHD13/Rag1−/− mice, including myeloid, B-cell, T-cell, and erythroid leukemias. In the SPF environment provided, the WT/Rag1+/− and WT/Rag1−/− control groups showed no significant difference in survival rates. Serial CBC data indicated that there was no significant difference in the timing or degree of peripheral blood cytopenias between the NHD13+ /Rag1+/+ and NHD13/Rag1−/− mice, supporting the conclusion that absence of lymphocytes does not lead to improvement in the peripheral blood cytopenias caused by the NHD13 transgene. This observation suggests that the NHD13 transgene does not produce MDS caused by an autoimmune phenomenon. The poorer survival and increased frequency of leukemic transformation in the NHD13/Rag1−/− mice suggests that lymphocytes might play a role in the evolution of MDS to AML in the NHD13 mouse model, and supports the ‘immune surveillance' hypothesis. Disclosures: No relevant conflicts of interest to declare.

CD8+ suppressor and cytotoxic T cells recognize the same human leukocyte antigen-A2 restricted cytomegalovirus peptide

2008 ◽  
Vol 69 (11) ◽  
pp. 776-780 ◽  
Author(s):  
Haiyan Qin ◽  
George Vlad ◽  
Raffaello Cortesini ◽  
Nicole Suciu-Foca ◽  
John S. Manavalan
Keyword(s):  
T Cells ◽  
Human Leukocyte Antigen ◽  
Cytotoxic T Cells ◽  
Human Leukocyte ◽  
Leukocyte Antigen

scholarly journals Cytotoxic CD4 T Cells in Antiviral Immunity

2011 ◽  
Vol 2011 ◽  
pp. 1-8 ◽  
Author(s):  
Nikki B. Marshall ◽  
Susan L. Swain
Keyword(s):  
T Cells ◽  
Cd4 T Cells ◽  
Protective Immunity ◽  
Cytotoxic T Cells ◽  
Immune Surveillance ◽  
Antiviral Immunity ◽  
Effective Vaccine ◽  
Antigenic Determinants ◽  
The Many ◽  
And Function

CD4 T cells that acquire cytotoxic phenotype and function have been repeatedly identified in humans, mice, and other species in response to many diverse pathogens. Since CD4 cytotoxic T cells are able to recognize antigenic determinants unique from those recognized by the parallel CD8 cytotoxic T cells, they can potentially contribute additional immune surveillance and direct effector function by lysing infected or malignant cells. Here, we briefly review much of what is known about the generation of cytotoxic CD4 T cells and describe our current understanding of their role in antiviral immunity. Furthering our understanding of the many roles of CD4 T cells during an anti-viral response is important for developing effective vaccine strategies that promote long-lasting protective immunity.

scholarly journals CD86+ or HLA-G+ can be transferred via trogocytosis from myeloma cells to T cells and are associated with poor prognosis

Blood ◽  
2012 ◽  
Vol 120 (10) ◽  
pp. 2055-2063 ◽  
Author(s):  
Ross Brown ◽  
Karieshma Kabani ◽  
James Favaloro ◽  
Shihong Yang ◽  
P. Joy Ho ◽  
...  
Keyword(s):  
T Cells ◽  
T Cell ◽  
Poor Prognosis ◽  
Plasma Cells ◽  
Side Population ◽  
Immune Surveillance ◽  
Human Leukocyte ◽  
Cell Receptor ◽  
Lymphocytic Leukemia ◽  
Leukocyte Antigen

Abstract The transfer of membrane proteins between cells during contact, known as trogocytosis, can create novel cells with a unique phenotype and altered function. We demonstrate that trogocytosis is more common in multiple myeloma (MM) than chronic lymphocytic leukemia and Waldenstrom macroglobulinaemia; that T cells are more probable to be recipients than B or natural killer cells; that trogocytosis occurs independently of either the T-cell receptor or HLA compatibility; and that after trogocytosis, T cells with acquired antigens can become novel regulators of T-cell proliferation. We screened 168 patients with MM and found that CD86 and human leukocyte antigen G (HLA-G) were antigens commonly acquired by T cells from malignant plasma cells. CD3+CD86acq+ and CD3+ HLA-Gacq+ cells were more prevalent in bone marrow than peripheral blood samples. The presence of either CD86 or HLA-G on malignant plasma cells was associated with a poor prognosis. CD38++ side population cells expressed HLA-G, suggesting that these putative myeloma stem cells could generate immune tolerance. HLA-G+ T cells had a regulatory potency similar to natural Tregs, thus providing another novel mechanism for MM to avoid effective immune surveillance.

scholarly journals Dickkopf-1 (DKK1) is a widely expressed and potent tumor-associated antigen in multiple myeloma

Blood ◽  
2007 ◽  
Vol 110 (5) ◽  
pp. 1587-1594 ◽  
Author(s):  
Jianfei Qian ◽  
Jin Xie ◽  
Sungyoul Hong ◽  
Jing Yang ◽  
Liang Zhang ◽  
...  
Keyword(s):  
Multiple Myeloma ◽  
T Cells ◽  
Cell Lines ◽  
Cytotoxic T Cells ◽  
Human Leukocyte ◽  
Myeloma Cell ◽  
Low Frequencies ◽  
Myeloma Cells ◽  
Dickkopf 1

Abstract The identification of novel tumor-associated antigens, especially those shared among patients, is urgently needed to improve the efficacy of immunotherapy for multiple myeloma (MM). In this study, we examined whether Dickkopf-1 (DKK1), a protein that is not expressed in most normal tissues but is expressed by tumor cells from almost all patients with myeloma, could be a good candidate. We identified and synthesized DKK1 peptides for human leukocyte antigen (HLA)–A*0201 and confirmed their immunogenicity by in vivo immunization in HLA-A*0201 transgenic mice. We detected, using peptidetetramers, low frequencies of DKK1 peptide-specific CD8-positive (CD8+) T cells in patients with myeloma and generated peptide-specific T-cell lines and clones from HLA-A*0201-positive (HLA-A*0201+) blood donors and patients with myeloma. These T cells efficiently lysed peptide-pulsed but not unpulsed T2 or autologous dendritic cells, DKK1-positive (DKK1+)/HLA-A*0201+ myeloma cell lines U266 and IM-9, and, more importantly, HLA-A*0201+ primary myeloma cells from patients. No killing was observed on DKK1+/HLA-A*0201-negative (HLA-A*0201−) myeloma cell lines and primary myeloma cells or HLA-A*0201+ normal lymphocytes, including B cells. These results indicate that these T cells were potent cytotoxic T cells and recognized DKK1 peptides naturally presented by myeloma cells in the context of HLA-A*0201 molecules. Hence, our study identifies DKK1 as a potentially important antigen for immunotherapy in MM.

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