Abstract 2251: Analysis of cancer survival using peripheral blood immunological parameters

The purpose of this study is to use Immunological Evaluation of Peripheral Blood NK cell number to predict survival in the War of the Immune System against cancer. Comparison of the two survival curves starts with the null hypothesis: there is no difference between the top 50% NK vs bottom 50% NK survival curves. P value is derived from Test Statistic found using log rank test. Breast cancer patients and colon cancer patients were evaluated. Both showed statistically significant differences in survival based on NK Cell number. Eight breast cancer patients had local radiation which showed in every one that the peripheral blood NK cell number decreased during radiation and returned to baseline values after radiation ended. In colon cancer patients the level of quantitative IgM and IgA defined a difference in overall survival. This was not the case for breast cancer patients. Survival was evaluated over a 9+ year period in a single California practice.

Citation Format: R. Michael Williams, Joaquin Zuniga, Julio Granados, Edmond Tato Feris, Edmond J. Yunis. Analysis of cancer survival using peripheral blood immunological parameters [abstract]. In: Proceedings of the Annual Meeting of the American Association for Cancer Research 2020; 2020 Apr 27-28 and Jun 22-24. Philadelphia (PA): AACR; Cancer Res 2020;80(16 Suppl):Abstract nr 2251.

The immunogenetic diversity of the HLA system in Mexico correlates with underlying population genetic structure

We studied HLA class I (HLA-A, -B) and class II (HLA-DRB1, -DQB1) allele groups and alleles by PCR-SSP based typing in a total of 15,318 mixed ancestry Mexicans from all the states of the country divided into 78 sample sets, providing information regarding allelic and haplotypic frequencies and their linkage disequilibrium, as well as admixture estimates and genetic substructure. We identified the presence of 4268 unique HLA extended haplotypes across Mexico and find that the ten most frequent (HF > 1%) HLA haplotypes with significant linkage disequilibrium (Δ'≥0.1) in Mexico (accounting for 20% of the haplotypic diversity of the country) are of primarily Native American ancestry (A*02~B*39~DRB1*04~DQB1*03:02, A*02~B*35~DRB1*08~DQB1*04, A*68~B*39~DRB1*04~DQB1*03:02, A*02~B*35~DRB1*04~DQB1*03:02, A*24~B*39~DRB1*14~DQB1*03:01, A*24~B*35~DRB1*04~DQB1*03:02, A*24~B*39~DRB1*04~DQB1*03:02, A*02~B*40:02~DRB1*04~DQB1*03:02, A*68~B*35~DRB1*04~DQB1*03:02, A*02~B*15:01~DRB1*04~DQB1*03:02). Admixture estimates obtained by a maximum likelihood method using HLA-A/-B/-DRB1 as genetic estimators revealed that the main genetic components in Mexico as a whole are Native American (ranging from 37.8% in the northern part of the country to 81.5% in the southeastern region) and European (ranging from 11.5% in the southeast to 62.6% in northern Mexico). African admixture ranged from 0.0 to 12.7% not following any specific pattern. We were able to detect three major immunogenetic clusters correlating with genetic diversity and differential admixture within Mexico: North, Central and Southeast, which is in accordance with previous reports using genome-wide data. Our findings provide insights into the population immunogenetic substructure of the whole country and add to the knowledge of mixed ancestry Latin American population genetics, important for disease association studies, detection of demographic signatures on population variation and improved allocation of public health resources.

Acquired immune deficiency of cancer: Evaluation of NK cell number as a predictor of overall survival in breast cancer

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Background: Cancer specialists, be they molecular geneticists or oncology clinicians, now accept the fact that a cancer results after a deleterious mutation in the apoptosis program AND failure of the immune system, innate (non-specific) and adaptive (specific), to eliminate the now abnormal transformed cell and it's progeny. Just as the acquired immune deficiency syndrome existed as a syndrome BEFORE the HIV virus was described, the disease AIDS/HIV was designated because the virus explained the syndrome and made HIV/AIDS a disease. We believe cancer works the same way. Cancer is a failure of surveillance by the immune system which leads to a disease, one we have described as AIDS/cancer (J Immunol May 1, 2019, 202, 1S, 182.79). Methods: Commercially available laboratory analysis of peripheral blood (Quest Diagnostics) and standard treatment protocols for breast cancer. Results: The immune system can be evaluated with samples of peripheral blood where cell subsets, antibody levels, etc. are measurable. Here we present results from over 200 unselected breast cancer patients, independent of Stage. All patients were treated with standard protocols. The initial number of NK cells in peripheral blood, but not other cell subsets or immunoglobulin levels, are a, and likely the, most significant predictor for survival. Kaplan Meier survival analysis, done when 20% of the entire population had died, showed that none of the patients in the upper quartile for NK cell number had died. Survival differences, comparing the top 50% vs. bottom 50% in initial NK number. were also highly significant (P < 0.05). Conclusions: We conclude that the innate immune system, reflected as numbers of NK cells in the blood are the most significant predictor of survival.

The ImmunoGenetic Theory of Cancer Survival: Insights from the analysis of 200+ unselected breast cancer patients followed for over 8 years

The ImmunoGenetic approach to cancer survival has been out focus since we began collaborating in 1976. We both had had considerable experience studying the genetics and immunology of anti-cancer and autoimmune diseases related to thymus derived cells. RMW studied thymus derived cells with Byron Waksman and mouse MHC genetics with Baruj Benacerraf. EJY discovered the importance of T-cells in numerous mouse models, including breast cancer, with experiments he did in Robert Good’s laboratory. With Bernard Amos, EJY discovered the importance of more than one gene in the MHC of humans...HLA. Using published data we presented at AAI2019, the importance of homozygosity at the P2 site of Class I and the NG2A NK receptor. Innate and adaptive immune responses, involving NK cells and KIR IG receptors, are genetically controlled and appear substantially to involve natural killer cells. The mechanism is nonspecific (innate) in the killing process, but also specific (adaptive) through the KIR system inhibition of NK cell killing. Here we describe the facts that survival in breast cancer, regardless of stage at diagnosis is highly dependent on the number of NK cells in peripheral blood at the time of diagnosis. Survival is longer when NK cell number is high, when tested after surgical diagnosis. Treatments alter NK cells numbers in the blood. Radiation, even after an R0 surgery, results in a prompt decrease in peripheral blood NK cell number which then returns to baseline shortly after radiation stops. We conclude that NK cells are recruited to radiated sites. Baseline numbers of CD4+, CD8+, and CD19+ cells behave differently. The complex symphony of life is genetically controlled and extends cancer patients’ survival. Treatments are genetic and immunological.

Immunological Parameters in Blood (NK, CD4+ numbers, CD4/CD8 ratios, Ig levels, etc.) change with treatment (XRT, Chemotherapy, Immunotherapy etc.): Results in Breast Cancer, Colorectal Cancer and other sites (H&N, Lung, et. al.)

Our view of cancer and the immune system is that an immune deficiency/failure of immune surveillance results in immune dysregulation including a "hole" in the specificity repertoire that results in active tolerance (Tregs) to cancer antigens and common pathogens (Cell. Immunol. 1978). The genetic basis for cancer survival was described in the P815 mouse model for MHC linked IR-gene control (Williams, Dorf and Benacerraf, Ca. Res. 1974) and the method for application to man was described at AAI2012. At AAI2019 we described the Immunogenetic Theory of Cancer and Aging and defined the disease Acquired Immune Deficiency of Cancer. We described the fact that homozygosity at P2 of the leader peptide of HLA class I and at the NG2A NK cell receptor is associated with older age, longer survival after primary therapy for breast cancer and non-progression if HIV infection occurs. We showed that breast cancer survival is significantly longer among patients with higher numbers of NK cells at initial presentation for breast cancer treatment. Here we present data showing survival in colorectal cancer, just like in breast, is significantly better when NK cell numbers are higher at initial evaluation Presented also are data demonstrating that peripheral blood NK cell numbers decrease during radiation of the breast only to recover to baseline after XRT ends. There is little to no change in numbers of CD4+ cells and other immunological parameters. In colorectal cancer quantitative IgA are related to survival. This is not true in breast cancer. Quantitative IgM and IgG levels are not associated with survival in either breast or colorectal caner. We conclude that simple blood parameters can provide substantial insight about mechanisms of treatment in cancer survival.

Thinking Outside the Box: Innate- and B Cell-Memory Responses as Novel Protective Mechanisms Against Tuberculosis

Tuberculosis (TB) is currently the deadliest infectious disease worldwide. Failure to create a highly effective vaccine has limited the control of the TB epidemic. Historically, the vaccine field has relied on the paradigm that IFN-γ-mediated CD4+ T cell memory responses are the principal correlate of protection in TB. Nonetheless, the demonstration that other cellular subsets offer protective memory responses against Mycobacterium tuberculosis (Mtb) is emerging. Among these are memory-like features of macrophages, myeloid cell precursors, natural killer (NK) cells, and innate lymphoid cells (ILCs). Additionally, the dynamics of B cell memory responses have been recently characterized at different stages of the clinical spectrum of Mtb infection, suggesting a role for B cells in human TB. A better understanding of the immune mechanisms underlying such responses is crucial to better comprehend protective immunity in TB. Furthermore, targeting immune compartments other than CD4+ T cells in TB vaccine strategies may benefit a significant proportion of patients co-infected with Mtb and the human immunodeficiency virus (HIV). Here, we summarize the memory responses of innate immune cells and B cells against Mtb and propose them as novel correlates of protection that could be harnessed in future vaccine development programs.

Abstract 2343: Immunogenetics of cancer and aging

Antigen altered idiotype regulates specific immune responses (Cell Immunol. 1978: 4). Mendelian segregation of a given +/- phenotype defines an immune response gene (Benacerraf, Nobel). Autoimmunity producing anti-self clones must be eliminated or specifically suppressed, so a large portion of the antigenic repertoire resembles allogeneic MHC molecules (Medawar, Nobel). We proposed that exposure to many different allogeneic HLA molecules could cause specific immune suppression within the repertoire of epitopes and that these blank spots or holes in the universe of target antigens eventually would overlap with specificities including targets for eliminating pathogens such as viruses or tumor antigens. Some "holes" become large enough to result in an acquired immunodeficiency syndrome (AIDS) The opposite is also possible (Allogeneic Effect, Transplant Rev. 1972, 12; 141). This requires viable cells and cytokines released by host and/or donor. IR-genes for tumor resistance localize to the MHC. Class I/II MHC genes (Cancer Res. 1982; 35:1586) and NK cell receptor ligands (J. Stem Cell Res. 2007), regulate adaptive and innate immunity. We examined the combination of HLA specificities and the alleles of ligands of receptors of NK cells in breast cancer patients, HIV non progressors, and centenarians in Mexico. Immunological evaluation (CD4+,CD8+,CD19+ & NK cells and quantitative IgM, IgG, & IgA in breast cancer (BCA) patients in California. Overall survival (OS) depended on specificities (idiotypes) and the regulation of innate and adoptive immunity. The BCA patients and centenarians did not have HIV infection. People with more CD4 cells, more NK cells and more IgG, survive longer than those with the opposite immune profile. The immune specificity repertoire has evolved to avoid fatal autoimmunity, all orchestrated by T regs via T-cell antigen receptors and variable regions of Ig. The antigen receptors (CAR-T) and Ig variable region antigen receptors (Jerne, Nobel) are idiotypes, Single amino acid (AA) changes become altered "antigens" of the history of the patient: environment (e.g., microbiome), vaccination (e.g., BCG), and virus infections (Sendai or CMV in mice, HIV and/or others like HPV in man). This is true for single AA changes in both mice (H-2 mutants) and man; NK cell receptor ligands (Thr v Met). The results show profound effects on survival. Data, including MHC and NK receptor ligand phenotypes, OS and immunological evaluation of patients/people will be presented. Immunogenetic profiles of cancer survivors and long lived individuals are similar to those of HIV long term non progressors. Our data support our Immunogenetic Theory of Cancer and Aging.

Citation Format: RMichael Williams, Edmond J. Yunis. Immunogenetics of cancer and aging [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2019; 2019 Mar 29-Apr 3; Atlanta, GA. Philadelphia (PA): AACR; Cancer Res 2019;79(13 Suppl):Abstract nr 2343.

Role of natural killer cell activity in HIV infections, aging, and breast cancer survival

Natural killer cell activity participates in the elimination of tumors and virus infections. Data presented here include their role in a virus infection (HIV), metastatic breast cancer, and aging per se. We have analyzed two gene segments MHC HLA class I ligands and NK receptors Each have single amino acid differences. Together these alleles can identify long term survivors. Homozygosity of HLA–Bw4 supertype in HIV progression has been described. Since HLA-KIR genetic interactions of HLA-Bw4 with KIR (3DS1) only included Bw4, with the exception of B*27 and B*44 that use different mechanism of protection, on the clinical outcome of HIV infection, NK–ligand interactions (NKG2A-HLA-E with HLA class I leader peptides) explain the long term non-progressors (LTNP) to AIDS. HLA-B alleles have Methionine (Met) or Threonine (Thr) at second position (P2) of their leader peptide. HLA-Bw4 alleles, with exception of B*38, encode leader peptide with Thr at P2 and HLA-Bw6 genes that encode Met at P2 are B*07, B*08 and B*14. All others have Thr at P2. Comparisons of the Thr in LTNP with progressors, up to 15 years. with non-infected Caucasian controls were significant. Also, aged Mexicans demonstrated significant increase of homozygosity of Thr at P2 and Mexican patients with metastatic breast cancer were studied 10 years after treatment with surgery and chemotherapy,

The 39 survivors demonstrated significant increase of homozygosity of Thr at P2 compared to controls without cancer and the 37 non survivors. These findings need to be studied in different malignancies and different ethnicities as well as in mouse models. Our findings support the immunogenetic theory of cancer and aging.

Symphony of Life: Genetics, Immunology, Cancer & Aging I. Genetic and immunological evaluation of mice with histocompatible tumors, virus induced breast cancer and survivors of metastatic breast cancer, HIV infection, and old people

Antigen altered idiotype induces immune suppression through the production of a "hole" in the antigenic/epitope specificity repertoire, the consequences of which can be a acquired immune deficiency SYNDROME called AIDS. There are measurable immunological consequences which include decreased CD4 cell numbers and low CD4/CD8 ratios and uncommon DISEASES like pneumocystis carinii pneumonia, virus induced cancers such as CMV mediated Kaposi's sarcoma or HPV mediated cancers (Kaposi's sarcoma, cervical cancer, tonsil cancer, etc.) and other DISEASES for which no viral etiology has been proven (breast cancer, lung cancer, melanoma, anal cancer, colorectal cancer, etc.). When there is the double whammy of immune deficiency AND virus infection, particularly one which preferentially infects and/or kills a distinct cell population (CD4+ lymphocytes in man, MTV induced mammary cancer in mice) the disease such as AIDS/HIV or metastatic breast cancer, are particularly severe. The measurable components of the immune system (CD4 counts, CD4/CD8 ratios, Tregs, CTLs, quantitative immunoglobulins, NK cell numbers and NK cell activity and cytokine levels are altered. We will present data including genetic (MHC class I, NK cell receptor ligands) and immunological (cell numbers in old mice or humans, metastatic breast cancer or HIV infected people, and those who are older than 90. Populations tested include centenarians Mexico City, mice surviving after a Sendai virus epidemic or injection of a histocompatible tumor, active homosexuals, and long term survivors of breast cancer or HIV infection. Data include MHC class I allele interaction with NKG2A receptors in Mexicans, survivors of breast cancer and long term non progressors with HIV infection.

Targeting DEC-205-DCIR2+ dendritic cells promotes immunological tolerance in proteolipid protein-induced experimental autoimmune encephalomyelitis

Background

Dendritic cells (DC) induce adaptive responses against foreign antigens, and play an essential role in maintaining peripheral tolerance to self-antigens. Therefore they are involved in preventing fatal autoimmunity. Selective delivery of antigens to immature DC via the endocytic DEC-205 receptor on their surface promotes antigen-specific T cell tolerance, both by recessive and dominant mechanisms. We provide evidence that the induction of antigen-specific T cell tolerance is not a unique property of CD11c⁺CD8⁺DEC-205⁺ DCs.

Methods

We employed a fusion between αDCIR2 antibodies and the highly encephalitogenic peptide 139–151 of myelin-derived proteolipid protein (PLP_139–151), to target CD11c ⁺CD8^- DCs with a DEC-205−DCIR2⁺ phenotype in vivo, and to substantially improve clinical symptoms in the PLP_139–151-induced model of experimental autoimmune encephalomyelitis (EAE).

Results

Consistent with previous studies targeting other cell surface receptors, EAE protection mediated by αDCIR2-PLP_139–151 fusion antibody (Ab) depended on an immature state of targeted DCIR2⁺ DCs. The mechanism of αDCIR2-PLP_139–151 mAb function included the deletion of IL-17- and IFN-γ-producing pathogenic T cells, as well as the enhancement of regulatory T (Treg) cell activity. In contrast to the effect of αDEC-205⁺ fusion antibodies, which involves extrathymic induction of a Foxp3⁺ Treg cell phenotype in naïve CD4⁺Foxp3^- T cells, treatment of animals with DCIR2⁺ fusion antibodies resulted in antigen-specific activation and proliferative expansion of natural Foxp3⁺ Treg cells.

Conclusions

These results suggest that multiple mechanisms can lead to the expansion of the Treg population, depending on the DC subset and receptor targeted.

Electronic supplementary material

The online version of this article (10.1186/s10020-018-0017-6) contains supplementary material, which is available to authorized users.

Advances in HLA genetics

The major histocompatibility complex (MHC) is a genetic system of over 70 known genes that occupies the midportion of the short arm of the sixth chromosome (C6p) and spans about 4 million base pairs of DNA. The high-resolution typing of class I and class II MHC genes and the identification of genes between and near them has increased the definition of the genetic basis of immune responses and diseases of unknown etiology such as autoimmune diseases in man. Although there are many more genetic systems that participate in the rejection of tissues and in the immune response, the MHC plays a central role in tissue compatibility and immune response against cancer and infectious diseases. In this paper, the authors review evidence about the role of HLA polymorphism in the pathogenesis and development of cancer, infectious diseases, autoimmune diseases and transplantation.

HLA class I and class II conserved extended haplotypes and their fragments or blocks in Mexicans: implications for the study of genetic diversity in admixed populations

Major histocompatibility complex (MHC) genes are highly polymorphic and informative in disease association, transplantation, and population genetics studies with particular importance in the understanding of human population diversity and evolution. The aim of this study was to describe the HLA diversity in Mexican admixed individuals. We studied the polymorphism of MHC class I (HLA-A, -B, -C), and class II (HLA-DRB1, -DQB1) genes using high-resolution sequence based typing (SBT) method and we structured the blocks and conserved extended haplotypes (CEHs) in 234 non-related admixed Mexican individuals (468 haplotypes) by a maximum likelihood method. We found that HLA blocks and CEHs are primarily from Amerindian and Caucasian origin, with smaller participation of African and recent Asian ancestry, demonstrating a great diversity of HLA blocks and CEHs in Mexicans from the central area of Mexico. We also analyzed the degree of admixture in this group using short tandem repeats (STRs) and HLA-B that correlated with the frequency of most probable ancestral HLA-C/−B and -DRB1/−DQB1 blocks and CEHs. Our results contribute to the analysis of the diversity and ancestral contribution of HLA class I and HLA class II alleles and haplotypes of Mexican admixed individuals from Mexico City. This work will help as a reference to improve future studies in Mexicans regarding allotransplantation, immune responses and disease associations.

MHC Class II haplotypes of Colombian Amerindian tribes

We analyzed 1041 individuals belonging to 17 Amerindian tribes of Colombia, Chimila, Bari and Tunebo (Chibcha linguistic family), Embera, Waunana (Choco linguistic family), Puinave and Nukak (Maku-Puinave linguistic families), Cubeo, Guanano, Tucano, Desano and Piratapuyo (Tukano linguistic family), Guahibo and Guayabero (Guayabero Linguistic Family), Curripaco and Piapoco (Arawak linguistic family) and Yucpa (Karib linguistic family). for MHC class II haplotypes (HLA-DRB1, DQA1, DQB1). Approximately 90% of the MHC class II haplotypes found among these tribes are haplotypes frequently encountered in other Amerindian tribes. Nonetheless, striking differences were observed among Chibcha and non-Chibcha speaking tribes. The DRB1*04:04, DRB1*04:11, DRB1*09:01 carrying haplotypes were frequently found among non-Chibcha speaking tribes, while the DRB1*04:07 haplotype showed significant frequencies among Chibcha speaking tribes, and only marginal frequencies among non-Chibcha speaking tribes. Our results suggest that the differences in MHC class II haplotype frequency found among Chibcha and non-Chibcha speaking tribes could be due to genetic differentiation in Mesoamerica of the ancestral Amerindian population into Chibcha and non-Chibcha speaking populations before they entered into South America.

Interaction between immunoglobulin allotypes and NK receptor genes in diabetes post-hepatitis C virus infection

Genetic interactions between natural killer (NK) cells immunoglobulin-like receptor (KIR) genes and immunoglobulin allotypes have been previously reported in type 2 diabetes mellitus (DM) patients. Puerto Rican Americans with a history of intravenous drug use who developed DM following HCV infection (n=32) were compared to individuals infected with HCV without diabetes (n=121) and to DM non-infected individuals (n=95). Subjects were genotyped for KIRs and immunoglobulin allotypes. We found interactions of immunoglobulin allotypes KM3/KM3 with NK inhibitory receptors 2DL3/2DL3, 2DL1 in the absence of 2DS4 associated with susceptibility to DM in HCV infected individuals. These data suggest the possibility that a subset of patients with HCV could have an immune-mediated component contributing to the development of DM.

Molecular signatures distinguishing active from latent tuberculosis in peripheral blood mononuclear cells, after in vitro antigenic stimulation with purified protein derivative of tuberculin (PPD) or Candida: a preliminary report

Purified protein derivative (PPD) or tuberculin skin testing is used to identify infected individuals with Mycobacterium tuberculosis (Mtb) and to assess cell-mediated immunity to Mtb. In the present study, we compared PBMC cultures in the presence of tuberculin or Candida antigens using cytokine bead arrays and RNA microarrays. Measurements of different cytokines and chemokines in supernatants of PMBC cultures in the presence of PPD showed increased levels of interferon (IFN)-gamma in active tuberculosis infection (ATBI) and latent TB infected (LTBI) compared to controls, and increased levels of TNF-alpha in ATBI compared with LTBI. Also, we found increase of IL-6 in cultures of PPD positive and controls but not in the cultures with Candida. We also report the molecular signature of tuberculosis infection, in ATBI patients, the following genes were found to be up-regulated and absent in LTBI individuals: two kinases (JAK3 and p38MAPK), four interleukins (IL-7, IL-2, IL-6, and IFNbeta1), a chemokine (HCC-4) a chemokine receptor (CxCR5), two interleukin receptors (IL-1R2 and IL-18R1), and three additional ones (TRAF5, Smad2, CIITA, and NOS2A). By contrast, IL-17 and IGFBP3 were significantly up-regulated in LTBI. And, STAT4, GATA3, Fra-1, and ICOS were down-regulated in ATBI but absent in LTBI. Conversely, TLR-10, IL-15, DORA, and IKK-beta were down-regulated in LTBI but not in ATBI. Interestingly, the majority of the up-regulated genes found in ATBI were found in cultures stimulated with tuberculin (PPD) or Candida antigens, suggesting that these pathogens stimulate similar immunological pathways. We believe that the molecular signature distinguishing active from latent tuberculosis infection may require using cytokine bead arrays along with RNA microarrays testing cell cultures at different times following in vitro proliferation assays using several bacterial antigens and PPD.

Humoral immunity in tuberculin skin test anergy and its role in high-risk persons exposed to active tuberculosis

The most common test to identify latent tuberculosis is the tuberculin skin test that detects T cell responses of delayed type hypersensitivity type IV. Since it produces false negative reactions in active tuberculosis or in high-risk persons exposed to tuberculosis patients as shown in this report, we studied antibody profiles to explain the anergy of such responses in high-risk individuals without active infection. Our results showed that humoral immunity against tuberculin, regardless of the result of the tuberculin skin test is important for protection from active tuberculosis and that the presence of high antibody titers is a more reliable indicator of infection latency suggesting that latency can be based on the levels of antibodies together with in vitro proliferation of peripheral blood mononuclear cells in the presence of the purified protein derivative. Importantly, anti-tuberculin IgG antibody levels mediate the anergy described herein, which could also prevent reactivation of disease in high-risk individuals with high antibody titers. Such anti-tuberculin IgG antibodies were also found associated with blocking and/or stimulation of in vitro cultures of PBMC with tuberculin. In this regard, future studies need to establish if immune responses to Mycobacterium tuberculosis can generate a broad spectrum of reactions either toward Th1 responses favoring stimulation by cytokines or by antibodies and those toward diminished responses by Th2 cytokines or blocking by antibodies; possibly involving mechanisms of antibody dependent protection from Mtb by different subclasses of IgG.

Protective KIR-HLA interactions for HCV infection in intravenous drug users

Intravenous drug use has become the principal route of hepatitis C virus (HCV) transmission due to the sharing of infected needles. In this study, we analyzed the distribution of HLA-KIR genotypes among 160 Puerto Rican intravenous drug users (IDUs) with HCV infection and 92 HCV-negative Puerto Rican IDUs. We found a significant association between the presence of different combinations of KIR inhibitory receptor genes (KIR2DL2 and/or KIR2DL3, pC=0.01, OR=0.07; KIR2DL2 and/or KIR2DL3+KIR2DS4, pC=0.01, OR=0.39) and HLA-C1 homozygous genotypes (HLA-C1+KIR2DS4, pC=0.02, OR=0.43; HLA-C1+KIR2DL2+KIR2DS4, pC=0.02, OR=0.40) together with the activating receptor KIR2DS4 (HLA-C1+KIR2DS4+KIR2DL3 and/or KIR2DL2, pC=0.004, OR=0.38) with protection from HCV infection. Our findings in HCV-infected and non-infected IDUs suggest an important role for KIRs (KIR2DL2 and KIR2DL3) with group HLA-C1 molecules, in the presence of activating KIR2DS4, in protection from HCV infection. These results support the hypothesis that activator signaling, mediated by KIR2DS4, plays a determinant role in the regulation of NK cell antiviral-activity.

High resolution human leukocyte antigen (HLA) class I and class II allele typing in Mexican mestizo women with sporadic breast cancer: case-control study

BACKGROUND

The development of breast cancer is multifactorial. Hormonal, environmental factors and genetic predisposition, among others, could interact in the presentation of breast carcinoma. Human leukocyte antigen (HLA) alleles play an important role in immunity (cellular immunity) and may be important genetic traits. HLAAllele-specific interaction has not been well established. Recently, several studies had been conducted in order to do so, but the results are controversial and in some instances contradictory.

METHODS

We designed a case-control study to quantify the association of HLA class I and II genes and breast cancer. HLA typing was performed by high resolution sequence-specific oligotyping after DNA amplification (PCR-SSOP) of 100 breast cancer Mexican mestizo patients and 99 matched healthy controls.

RESULTS

HLA-A frequencies that we were able to observe that there was no difference between both groups from the statistical viewpoint. HLA-B*1501 was found three times more common in the case group (OR, 3.714; p = 0.031). HLA-Cw is not a marker neither for risk, nor protection for the disease, because we did not find significant statistical differences between the two groups. DRB1*1301, which is expressed in seven cases and in only one control, observing an risk increase of up to seven times and DRB1*1602, which behaves similarly in being present solely in the cases (OR, 16.701; 95% CI, 0.947 - 294.670). DQ*0301-allele expression, which is much more common in the control group and could be protective for the presentation of the disease (OR, 0.078; 95% CI, 0.027-0.223, p = 0.00001).

CONCLUSION

Our results reveal the role of the MHC genes in the pathophysiology of breast cancer, suggesting that in the development of breast cancer exists a disorder of immune regulation. The triggering factor seems to be restricted to certain ethnic groups and certain geographical regions since the relevant MHC alleles are highly diverse. This is the first study in Mexican population where high resolutions HLA typing has been performed in order to try to establish an association with malignancy.

Genetic interactions of KIR and G1M immunoglobulin allotypes differ in obese from non-obese individuals with type 2 diabetes

We analyzed the natural killer cell immunoglobulin-like receptor (KIR) genes and immunoglobulin allotypes in the development of type 2 diabetes (T2D) based on body mass index (BMI) measurements (obese vs. non-obese) in Puerto Rican Americans. Genetic interactions between the KIR haplotype A homozygotes (HAH) and its fraction containing two inhibitory receptors 2DL3 and 2DL1 and the activating receptor 2DS4 with immunoglobulin allotypes were studied. We found a significant association between the HAH and T2D (p=0.002; OR=7.97) and its interaction with the immunoglobulin allotype z: GM f/f (-) (p=<0.0001; OR, not determined) only in non-obese individuals. This association were due to the interactions between the 2DL3/2DL3, 2DL1/2DL1, and 2DS4 fragment with GM f/f (-) in T2D patients (p=0.0017; OR=3.45). Analysis based on BMI demonstrated associations in both obese (p=0.037; OR=2.43; 95% CI=0.97-6.31) and non-obese individuals (p=<0.0001; OR=8.38; 95% CI=2.49-29.31). By contrast, the interaction of the GM allotype f/f (-) with the HAH fragment was associated with T2D only in non-obese individuals (p=<0.0001; OR=18.2; 95% CI=3.71-113.4). As expected, interaction of both HAH and its fragment with HLA-C group's ligands were significant. We used informative short tandem repeats (STRs) that distinguish major populations to determine genetic admixture and found that there was no genetic stratification in our cohort. Our findings are consistent with the possibility of an autoimmune and/or innateimmune component in the pathogenesis of T2D: NK receptors with chronic inflammation in obese and genetic interactions with G1M allotype in T2D non-obese possibly mediating autoimmunity.

Possible role of natural killer cells in pemphigus vulgaris - preliminary observations

Pemphigus vulgaris (PV) is an autoimmune blistering disease that affects the skin and multiple mucous membranes, and is caused by antibodies to desmoglein (Dsg) 1 and 3. Natural killer (NK) cells have a role in autoimmunity, but their role in PV is not known. NK cells in the peripheral blood leucocytes (PBL) of 15 untreated Caucasian patients with active PV were studied and compared with healthy controls for the expression of major histocompatibility complex (MHC) class II and co-stimulatory molecules. CD56+ CD16- CD3- NK or CD56+ CD16+ CD3- NK cells from the PBL of PV patients co-express MHC class II and co-stimulatory molecule B7-H3 without exogenous stimulation. CD4+ T cells from the PBL and perilesional skin of PV patients were co-cultured with CD56+ CD3- NK cells from the PBL of the same patients; in the presence of Dsg3 peptides underwent statistically significant proliferation, indicating that NK cells functioned as antigen-presenting cells. Supernatants from these co-cultures and serum of the same patients with active PV had statistically significantly elevated levels of interleukin (IL)-6, IL-8 and interferon-gamma, compared with controls indicating that the NK cells stimulated CD4+ T cells to produce proinflammatory cytokines. In these experiments, we present preliminary evidence that NK cells may play a role in the pathobiology of PV.

Interaction of NK inhibitory receptor genes with HLA-C and MHC class II alleles in Hepatitis C virus infection outcome

Natural killer cells are important in innate defense against viral infections. The interplay between stimulatory and inhibitory natural killer cell receptors and their corresponding human leukocyte antigen ligands are known to influence the outcome of acute Hepatitis C virus infection. Frequencies of NK receptor genes (8 inhibitory, 6 activating and 2 pseudogenes) and HLA class II alleles (DRB1, DQB1) were analyzed in 160 Puerto-Rican American drug users with Hepatitis C virus infection; 121 had chronic viremia (CV) and 39 were spontaneous clearance (SC). We further ruled out genetic stratification using short tandem repeats. Interaction between KIR gene receptor 2DL3/2DL3 and its ligand, C1/C1 of HLA-Cw alleles and spontaneous clearance was confirmed (p=0.03, OR=3.05). We also found a new interaction between the KIR receptor gene 2DL3 with HLA-DRB1*1201 (p=0.0001, OR=22) associated with SC, and an association of HLA DQB1*0501 (p=0.05, OR=0.30) with CV. Our findings suggested a role for MHC class II alleles in Hepatitis C virus peptide presentation to T cells together with NK ligand interaction involving pathways that will be useful for the development of immunotherapeutic interventions.

NK cell inhibition receptor genes and HLA –DRB1*1201 in Spontaneous Clearance of Hepatitis Virus Infection. (35.16)

Host genetic factors play an important role in the evolution of hepatitis C virus (HCV) infection. The aim of this study was to analyze the MHC-KIR combinations associated with the susceptibility and clinical outcome of HCV infection in drug users with Puerto Rican American ethnic background. A total of 160 HCV infected drug users (121 with chronic viremia (CV) and 39 with spontaneous clearance (SC)). Frequencies of KIR inhibitory and activating receptors and MHC class I ligands in HCV infected patients were analyzed using DNA methods. We also used a novel approach to rule out genetic stratification. We report a significant association between HLA-C1/C1 and KIR2DL3/KIR2DL3 with SC was detected confirming previous studies in Caucasian and African Americans. In addition we found MHC class II associations with clinical outcome different to those reported in Caucasians. Our results support the existence of interactions between HLA-C1 and KIR2DL3 genes in HCV viral outcome consistent with loss of inhibition mediated by HLA-C1 and inhibitory functions of KIR2DL3 together with the presence of HLA-DRB1*1201 consistent with negative epistasis.