T-cell receptor V and J usage paired with specific HLA alleles associates with distinct cervical cancer survival rates

Association of the HLA-DQB1*02 allele with lower tauopathy in Alzheimer's disease

Although many studies have investigated the influence of HLA on the risk of Alzheimer's Disease (AD), there have been inconsistent results. Part of this problem has been attributed to limitations of a clinical assessment in the absence of histopathological confirmation or other quantitative assessments. This study employed a subset of the AD Sequencing Project, representing 2663 cases with histopathological confirmation of AD and confirmation of 881 cognitively normal cases. Two HLA allelic subtypes, DQB1*02:01 and DQB1*02:02, were associated with lower Braak staging, a measure of tauopathy in the brain. These HLA subtypes were also associated with a later age of onset. There was a lower occurrence of HLA-DQB1*02:01 and HLA-DQB1*02:02 in AD cases compared to cognitively normal cases. For all of the above results, replicative sets were confirmatory. The above results were also maintained for both HLA-DQB1*02:01 and HLA-DQB1*02:02 when removing the effect of APOE4 or APOE2. Interestingly, the HLA-DQB1*02 allele binds tau better than all other HLA-DQB1 alleles tested, per an in silico assessment, raising the question of whether deletion of tau binding, auto-reactive T-cells in the thymus could reduce the likelihood of the onset of AD?

Interpretable GWAS by linking clinical phenotypes to quantifiable immune repertoire components

Bridging the gap between genotype and phenotype in GWAS studies is challenging. A multitude of genetic variants have been associated with immune-related diseases, including cancer, yet the interpretability of most variants remains low. Here, we investigate the quantitative components in the T cell receptor (TCR) repertoire, the frequency of clusters of TCR sequences predicted to have common antigen specificity, to interpret the genetic associations of diverse human diseases. We first developed a statistical model to predict the TCR components using variants in the TRB and HLA loci. Applying this model to over 300,000 individuals in the UK Biobank data, we identified 2309 associations between TCR abundances and various immune diseases. TCR clusters predicted to be pathogenic for autoimmune diseases were significantly enriched for predicted autoantigen-specificity. Moreover, four TCR clusters were associated with better outcomes in distinct cancers, where conventional GWAS cannot identify any significant locus. Collectively, our results highlight the integral role of adaptive immune responses in explaining the associations between genotype and phenotype.

IGL CDR3 Hydropathy and Antigen Chemical Complementarity Associated with Greater Disease-Free Survival in Lung Adenocarcinoma: Implications for Gender Disparities

With lung cancer remaining a challenging disease, new approaches to biomarker discovery and therapy development are needed. Recent immunogenomics, adaptive immune receptor approaches have indicated that it is very likely that B cells play an important role in mediating better overall outcomes. As such, we assessed physicochemical features of lung adenocarcinoma resident IGL complementarity determining region-3 (CDR3) amino acid (AA) sequences and determined that hydrophobic CDR3 AA sequences were associated with a better disease-free survival (DFS) probability. Further, using a recently developed chemical complementarity scoring algorithm particularly suitable for the evaluation of large patient datasets, we determined that IGL CDR3 chemical complementarity with certain cancer testis antigens was associated with better DFS. Chemical complementarity scores for IGL CDR3-MAGEC1 represented a gender bias, with an overrepresentation of males among the higher IGL-CDR3-CTA complementarity scores that were in turn associated with better DFS (logrank p < 0.065). Overall, this study pointed towards potential biomarkers for prognoses that, in some cases are likely gender-specific; and towards biomarkers for guiding therapy, e.g., IGL-based opportunities for antigen targeting in the lung cancer setting.

TCR gene segment usage and HLA alleles that are associated with cancer survival rates also represent racial disparities

Understanding racial disparities in cancer outcomes continues to be a challenge, with likely many factors at play, including socioeconomic factors and genetic polymorphisms impacting basic cellular and molecular functions. Additionally, it is possible that specific combinations of environment and genetics have specific impacts. T-cell receptor (TCR) gene segment usage, HLA allele combinations have been associated with autoimmune and infectious disease courses, and more recently, TCR gene segment usage, HLA allele combinations have been associated with distinct survival outcomes in cancer as well. We examined several such, previously reported cancer-related TCR gene segment usage, HLA allele combinations for evidence of racial disparities, with regard to the prevalence of the combination in different racial groups. Results indicated that TCR gene segment usage, potentially reflecting environmental factors related to previous pathogen exposure, in combination with certain HLA alleles or independently, may represent a novel explanation for racial disparities in cancer outcomes. Overall, at this point, a genetic connection to racial disparities in cancer outcomes is detectable but remains modest, suggesting that other factors, such as socioeconomic factors, remain as important considerations.

Immunogenomics Parameters for Patient Stratification in Alzheimer's Disease

BACKGROUND

Despite the fact that only modest adaptive immune system related approaches to treating Alzheimer's disease (AD) are available, an immunogenomics approach to the study of AD has not yet substantially advanced.

OBJECTIVE

Thus, we sought to better understand adaptive immune receptor chemical features in the AD setting.

METHODS

We characterized T-cell receptor alpha (TRA) complementarity determining region-3 (CDR3) physicochemical features and identified TRA CDR3 homology groups, represented by TRA recombination reads extracted from 2,665 AD-related, blood- and brain-derived exome files.

RESULTS

We found that a higher isoelectric value for the brain TRA CDR3s was associated with a higher (clinically worse) Braak stage and that a number of TRA CDR3 chemical homology groups, in particular representing bloodborne TRA CDR3s, were associated with higher or lower Braak stages. Lastly, greater chemical complementarity of both blood- and brain-derived TRA CDR3s and tau, based on a recently described CDR3-candidate antigen chemical complementarity scoring process (https://adaptivematch.com), was associated with higher Braak stages.

CONCLUSION

Overall, the data reported here raise the questions of (a) whether progression of AD is facilitated by the adaptive immune response to tau; and (b) whether assessment of such an anti-tau immune response could potentially serve as a basis for adaptive immune receptor related, AD risk stratification?

Specific TCR V-J gene segment recombinations leading to the identification pan-V-J CDR3s associated with survival distinctions: diffuse large B-cell lymphoma

In the diffuse large B-cell lymphoma (DLBCL) setting, we examined lymph node biopsy, T-cell receptor features, and the DLBLC patient human leukocyte antigen (HLA) alleles, to provide a basis for assessing survival distinctions represented by the National Cancer Institute Center for Cancer Research (NCICCR) dataset. While previous analyses of other cancer datasets have indicated that specific T-cell receptor (TCR) V or J gene segments, independently, can be associated with a survival distinction, we have here identified V-J recombinations, representing specific V and J gene segments associated with survival distinctions. As specific V-J recombinations represent relatively conserved complementarity determining region-3 (CDR3) amino acid sequences, we assessed the entire DLBCL NCICCR dataset for such conserved CDR3 features. Overall, this approach indicated the opportunity of identifying DLBCL patient subpopulations with TCR CDR3 features, and HLA alleles, with significant survival distinctions, possibly identifying cohorts more likely to benefit from a given immunotherapy.

A comparison of immune receptor recombination databases sourced from tumour exome or RNAseq files: Verifications of immunological distinctions between primary and metastatic melanoma

It became apparent several years ago that RNAseq and exome files prepared from tissue could be mined for adaptive immune receptor (IR) recombinations, which has given extra value to datasets originally intended for gene expression or mutation studies. For example, recovery of IR recombination reads from tumour specimen genomics files can correlate with survival rates. In particular, many benchmarking processes have been applied to the two sets of the IR recombination reads obtained from the cancer genome atlas files, but these two sets have never been directly compared. Here we show that both sets largely agree regarding several parameters. For example, recovery of TRB recombination reads from both WXS and RNAseq files representing metastatic melanoma was associated with a better outcome (p < .0004 in both cases); and T-cell receptor recombination read recovery, for both genomics file types, associated very strongly with T-cell gene expression markers. However, the use of CDR3 chemical features for survival distinctions was not consistent. This topic, and the surprising result that both datasets indicated that primary melanoma with recovery of IR recombination reads, in stark contrast to metastatic melanoma, represents a worse outcome, are discussed.

Electrostatic Complementarity of T-Cell Receptor-Alpha CDR3 Domains and Mutant Amino Acids Is Associated with Better Survival Rates for Sarcomas

While sarcoma immunology has advanced with regard to basic, and even some applied topics, this disease has not been subject to more recent immunogenomics approaches. Thus, we assessed the immune receptor recombinations available from the cancer genome atlas (TCGA) sarcoma database via tumor sample exome and RNASeq files. Results indicated that recovery of T-cell receptor-alpha recombination reads (TRA) correlated with a better survival rate, with the expression of T-cell biomarkers, and with tumor sample apoptosis signatures consistent with the longer patient survival times. Furthermore, samples representing TRA complementarity determining region-3 (CDR3) net charge per residue (NCPR) based complementarity with the corresponding sarcoma mutanome had a better survival rate, and more granzyme expression, than samples lacking such complementarity. By specifically using RNASeq-recovered TRA CDR3s and related NCPR assessments, three genes, TP53, ATRX, and RB1, were identified as being key components of the mutanome-based complementarity. Thus, these genes may represent key immune system targets for soft tissue sarcomas. Also, several key results from above were reproduced with a pediatric osteosarcoma dataset, work that led to identification of MUC6 mutations as potentially linked to a strong immune response. In sum, TRA CDR3s are likely to be important prognostic indicators, and possibly a beginning tool for immunotherapy development strategies, for adult and pediatric sarcomas.

Specific HLA alleles, paired with TCR V- and J-gene segment usage, link to distinct multiple myeloma survival rates

Multiple myeloma (MM) immunogenomics studies related to T-cell characterizations and involving large patient sets have been lacking, particularly in comparison to solid tumor types. Thus, we evaluated (i) HLA alleles, and (ii) T-Cell Receptor (TCR) V- and J-gene segment, HLA allele combinations, based on TCR recombinations in blood samples, for their potential associations with overall survival distinctions among an MM cohort. Two HLA alleles, and seven TCR V- or J-gene segment, HLA allele combinations were found to be associated with distinct overall survival rates. For examples, HLA-C*08:02, and the TRAV19, HLA-C*07:01 combination, were found to be associated with negative outcomes. In addition, anti-cytomegalovirus immune receptor sequences, from blood samples, were found to be associated with a positive outcome (p = 0.012, n = 278). These data, and other related immunogenomics data, indicate a potential opportunity to use personal immunogenetics parameters as guides to prognosis and therapies.

TRBV and TRBJ usage, when paired with specific HLA alleles, associates with distinct head and neck cancer survival rates

Common or dominant, T-cell receptor (TCR), V and J usage, in combination with particular human leukocyte antigen (HLA) alleles, has been associated with differing outcomes in viral infections, autoimmunity, and more recently, in cancer. Cervical cancer in particular represents the most dramatic series of distinctions of outcomes associated with differing combinations of dominant V or J usage and HLA alleles, possibly because of the strong association of cervical cancer with human papilloma virus (HPV), in turn leading to a likely molecular consistency in the mechanism of HPV antigen presentation. Thus, we considered assessing TRB V and J usage, HLA allele combinations, for their associations with survival rates and related data, in the cancer genome atlas head and neck cancer dataset. We obtained the TRB VDJ recombination reads from both the blood and tumor exome files and determined the V and J identities. We then established case ID (patient) subsets of V or J usage, HLA alleles, and determined, for example, that the TRBJ2-7, HLA-B*40:01 combination was associated with a better disease free survival rate than were either the TRBJ1-3, HLA-DPB1*03:01 or the TRBJ2-1, HLA-DPB1*02:01 combinations. Furthermore, these analyses led to the conclusion that TRBJ1-5 usage, and the HLA-C*08:02 and HLA-DRB1*03:01 alleles, had independent associations with distinct overall survival rates. In sum, the results suggest that dominant V or J usage, HLA allele combinations, and in certain cases, dominant V or J usage independently of HLA, could be useful in prognosis and in guiding immunotherapies.

Mining of prognosis-related genes in cervical squamous cell carcinoma immune microenvironment

Purpose

The aim of this study was to explore the effective immune scoring method and mine the novel and potential immune microenvironment-related diagnostic and prognostic markers for cervical squamous cell carcinoma (CSSC).

Materials and Methods

The Cancer Genome Atlas (TCGA) data was downloaded and multiple data analysis approaches were initially used to search for the immune-related scoring system on the basis of Estimation of STromal and Immune cells in MAlignant Tumour tissues using Expression data (ESTIMATE) algorithm. Afterwards, the representative genes in the gene modules correlated with immune-related scores based on ESTIMATE algorithm were further screened using Weighted Gene Co-expression Network Analysis (WGCNA) and network topology analysis. Gene functions were mined through enrichment analysis, followed by exploration of the correlation between these genes and immune checkpoint genes. Finally, survival analysis was applied to search for genes with significant association with overall survival and external database was employed for further validation.

Results

The immune-related scores based on ESTIMATE algorithm was closely associated with other categories of scores, the HPV infection status, prognosis and the mutation levels of multiple CSCC-related genes (HLA and TP53). Eighteen new representative immune microenvironment-related genes were finally screened closely associated with patient prognosis and were further validated by the independent dataset GSE44001.

Conclusion

Our present study suggested that the immune-related scores based on ESTIMATE algorithm can help to screen out novel immune-related diagnostic indicators, therapeutic targets and prognostic predictors in CSCC.

A scoring system for the electrostatic complementarities of T-cell receptors and cancer-mutant amino acids: multi-cancer analyses of associated survival rates

The anti-tumor immune response is considered to be due to the T-cell receptor (TCR) binding to tumor antigens, which can be either wild-type, early stem cell proteins, presumably foreign to a developed immune system; or mutant peptides, foreign to the immune system because of a mutant amino acid (aa) or otherwise somatically altered aa sequence. Recently, very large numbers of TCR complementarity-determining region-3 (CDR3) aa sequences obtained from tumor specimens have become available. We developed a novel algorithm for assessing the complementarity of tumor mutant peptides and TCR CDR3s, based on the retrieval of TCR CDR3 aa sequences from both tumor specimen and patient blood exomes and by using an automated process of assessing CDR3 and mutant aa electrical charges. Results indicated many instances where high electrostatic complementarity was associated with a higher survival rate. In particular, our approach led to the identification of specific genes contributing significantly to the complementary, TCR CDR3-mutant aa. These results suggest a novel approach to tumor immunoscoring and may lead to the identification of high-priority neo-antigen, peptide vaccines; or to the identification of ex vivo stimulants of tumor-infiltrating lymphocytes.

TRAV gene segments further away from the TRAJ gene segment cluster appear more commonly in human tumor and blood samples

We considered the possibility that the greater the distance between an immune receptor V and J, the more likely the V usage. Such a hypothesis is supported by results from mouse experiments. And, such a hypothesis is consistent with the fundamental nature of recombination and genomic distance: the further the distance, the greater the chance of a DNA break. Thus, we exploited the vast dataset of V and J recombination reads available for the human TRA gene, particularly from cancer and blood specimens, to assess the frequency of TRAV usage with respect to distance from the TRAJ cluster. Results indicated that, indeed, over the entire TRAV cluster, there is a greater chance of V usage the further the distance from the J cluster. These results do not address causation, and are not consistent for certain individual V gene segments, but the results do indicate that overall, the larger the distance between the V and J gene segment cluster, the more likely the appearance of at least a subset of TRAV segments, particularly among tumor infiltrating lymphocytes. With a similar approach, the distal TRAV gene segments were also found to be more commonly associated with a subset of distal TRAJ segments. These results have implications for restrictions on the apparent TRA repertoire in disease settings.