Immune profile of primary and recurrent epithelial ovarian cancer cases indicates immune suppression, a major cause of progression and relapse of ovarian cancer.

BACKGROUND: Ovarian cancer is the third most prevalent cancer in Indian women. Relative frequency of High grade serous epithelial ovarian cancer (HGSOC) and its associated deaths are highest in India which suggests the importance of understanding their immune profiles for better treatment modality. Hence, the present study investigated the NK cell receptor expression, their cognate ligands, serum cytokines, and soluble ligands in primary and recurrent HGSOC patients. We have used multicolor flow cytometry for immunophenotyping of tumor infiltrated and circulatory lymphocytes. Procartaplex, and ELISA were used to measure soluble ligands and cytokines of HGSOC patients. RESULTS: Among the enrolled 51 EOC patients, 33 were primary high grade serous epithelial ovarian cancer (pEOC) and 18 were recurrent epithelial ovarian cancer (rEOC) patients. Blood samples from 46 age matched healthy controls (HC) were used for comparative analysis. Results revealed, frequency of circulatory CD56Bright NK, CD56Dim NK, NKT-like, and T cells was reduced with activating receptors while alterations in immune subsets with inhibitory receptors were observed in both groups. Study also highlights differential immune profile of primary and recurrent ovarian cancer patients. We have found increased soluble MICA which might have acted as "decoy" molecule and could be a reason of decrease in NKG2D positive subsets in both groups of patients. Furthermore, elevated level of serum cytokines IL-2, IL-5, IL-6, IL-10, and TNF-α in ovarian cancer patients, might be associated with ovarian cancer progression. Profiling of tumor infiltrated immune cells revealed the reduced level of DNAM-1 positive NK and T cells in both groups than their circulatory counterpart, which might have led to decrease in NK cell's ability of synapse formation. CONCLUSIONS: The study brings out differential receptor expression profile on CD56BrightNK, CD56DimNK, NKT-like, and T cells, cytokines levels and soluble ligands which may be exploited to develop alternate therapeutic approaches for HGSOC patients. Further, few differences in the circulatory immune profiles between pEOC and rEOC cases, indicates the immune signature of pEOC undergoes some changes in circulation that might facilitated the disease relapse. They also maintains some common immune signatures such as reduced expression of NKG2D, high level of MICA as well as IL-6, IL10 and TNF-α, which indicates irreversible immune suppression of ovarian cancer patients. It is also emphasized that a restoration of cytokines level, NKG2D and DNAM-1on tumor infiltrated immune cells may be targeted to develop specific therapeutic approaches for high-grade serous epithelial ovarian cancer.

Human leukocyte antigens class I and class II alleles associated with vertical human immunodeficiency virus transmission - an exploratory study from Mumbai, India.

Background Human leukocyte antigens (HLA) an important host genetic factor is responsible for influencing human immunodeficiency virus/acquired immunodeficiency syndrome (HIV/AIDS) transmission and disease progression. Contributions of HLA I and II alleles have not been reported in the Indian population with respect to vertical HIV transmission. Aim In the current study we determined the frequencies of HLA class I and class II alleles in a cohort of children exposed to HIV through their mothers. Method In this exploratory study children perinatally exposed to HIV-1 who fit the study criteria and had completed 18 month follow-up were typed for HLA class I and class II alleles using polymerase chain reaction combined with sequence-specific oligonucleotides probes (PCR-SSOP) and sequence-specific primer (SSP) method. HLA typing was done in 30 positive and 60 HIV negative children along with confounding factors such as treatment regimens, viral load and CD4 count of the mother, feeding option, etc. SPSS software was used for statistical analysis and online docking tools for in-silico analysis. Results HLA-B*40 (p = 0.018) was significantly higher in negative children and was associated with protection, whereas HLA-A*01 (p = 0.05), HLA-B*37 (p = 0.032) and HLA-DRB1*09 (p = 0.017) were associated with transmission. Known protective allele HLA-B*27 was only present in negative children. Many specific haplotypes were exclusively present in the negative children or the positive ones. In-silico analysis was performed to predict the ability of HLA-B*40 to bind to antigenic peptides obtained from HIV-1 sequences in our study group. Limitations Small sample size is a concerning limitation of the study. Nonetheless this is a comprehensive study on HLA alleles in HIV exposed Indian children Conclusion Our study highlights the contribution of HLA class I and II alleles in the Indian children and further adds to understanding the immunogenetic mechanisms. These can be developed as markers for prediction of infection transmission. The observations also contribute to the database of genetic makeup of our population and can help in designing vaccine strategies.

Killer cell immunoglobulin-like receptor (KIR) gene contents: Are they associated with cervical cancer?

Killer cell immunoglobulin-like receptors (KIRs) are required for natural killer cell function against virus-infected cells or tumor cells. KIR gene content polymorphisms in Indian women with cervical cancer (CaCx) remain unexplored. Hence, we analyzed the frequencies of KIR genes, KIR haplotypes, and Bx subsets to draw their association with CaCx. The polymerase chain reaction-sequence-specific primer method was used for KIR genotyping in three groups of women: healthy controls (n = 114), women with human papillomavirus (HPV) infection (n = 70), and women with CaCx (n = 120). The results showed that the frequency of KIR2DS5 was significantly higher in women with CaCx compared to women with HPV infection (p = 0.02) and healthy controls (p = 0.01). Whereas the frequency of KIR2DL5B was significantly higher in healthy controls than in women with HPV infection (p = 0.02). The total number of activating KIR genes was higher in women with CaCx than in healthy controls (p = 0.006), indicating their positive association with CaCx. Moreover, the C4T4 subset was higher in women with CaCx than in women with HPV infection, though not significant. In conclusion, our findings highlight KIR2DS5, the C4T4 subset, and activating KIR genes are susceptible factors or positively associated with CaCx. Besides KIR2DL5B, this study also reported for the first time significantly high frequency of KIR2DL1 in healthy controls, indicating its possible protective association against CaCx. Further, significantly high frequency of KIR2DL3 observed in HPV-infected women might be also a promising biomarker for viral infections. Thus, the study confirms the association of KIR genes with cervical cancer in women with HPV infection.

Immune Profile of Blood, Tissue and Peritoneal Fluid: A Comparative Study in High Grade Serous Epithelial Ovarian Cancer Patients at Interval Debulking Surgery.

High-grade serous epithelial ovarian carcinoma (HGSOC) is an immunogenic tumor with a unique tumor microenvironment (TME) that extends to the peritoneal cavity. The immunosuppressive nature of TME imposes the major challenge to develop effective treatment options for HGSOC. Interaction of immune cells in TME is an important factor. Hence, a better understanding of immune profile of TME may be required for exploring alternative treatment options. Immune profiling of peritoneal fluid (PF), tumor specimens, and blood were carried out using flowcytometry, ELISA, and Procartaplex immunoassay. The frequency of CD56BrightNK cells and expression of functional receptors were reduced in PF. Increased activating NKp46+CD56DimNK cells may indicate differential antitumor response in PF. Functional receptors on NK, NKT-like and T cells were reduced more drastically in tumor specimens. Soluble ligands MIC-B and PVR were reduced, whereas B7-H6 was increased in PF. Dissemination of tumor cells contributes to soluble ligands in PF. A differential cytokine profile was found in serum and PF as IL-2, IL-8, IL-15, IL-27, IFN-γ, and GM-CSF were elevated specifically in PF. In conclusion, the differential immune profile and correlation of soluble parameters and NK cell receptors with chemo response score may add knowledge to understand anti-tumor immune response to develop effective treatment modality.

Human Papillomavirus E6/E7 oncogene transcripts as biomarkers for the early detection of cervical cancer.

Cancer of the cervix uteri is the fourth most common cancer worldwide with a high mortality rate. Due to limitations of the existing methods, alternative methods for triage are needed for early detection of cervical cancer precursors before progression to high-grade disease. The aim of this study was to evaluate human papillomavirus (HPV) E6/E7 oncogene expression as markers for early identification of cervical cancer risk in women with minor cytological abnormalities and in those with negative cytology. The detection of HPV was done using PCR and confirmed by southern hybridization. The high-risk (HR) and low-risk HPV types were identified by HPV typing. HPV DNA-positive patients were further tested for markers of oncogene expression by real-time PCR. Out of the women screened, 54/512 (10.54%) women tested positive for HPV infection. HR HPV DNA was found in 32/485 (6.60%) women with normal cytology (Pap negative) and 22/27 (81.5%) atypical squamous cells of undetermined significance/low-grade intraepithelial lesion cases. HR HPV E6/E7 oncogene transcripts were detected in 36/512 (7.03%) patients. The positivity rate of E6/E7 messenger RNA (mRNA) was 2.48% (12/485) in normal cervical cytology group and 88.9% (24/27) in abnormal cervical cytology group. The HPV E6/E7 mRNA test sensitivity was found to be 88.89% and specificity was 97.53%. In comparison, the sensitivity of the HPV DNA test was found to be 81.48% and specificity was 93.40%. In conclusion, E6 and E7 transcripts could provide a sensitive, early predictor of cervical cancer risk in women with normal cytology and minor cytological alterations.

Th1 cytokine gene polymorphism and the corresponding plasma cytokine levels: A comparative study in HIV-1 positive and exposed uninfected infants.

The pro-inflammatory (Th1) cytokines namely interleukin (IL)-2, IL-6, IL-12, interferon (IFN)-γ, tumor necrosis factor-α (TNF-α) are vital in the clearance of HIV infection. This prospective cohort study aimed to evaluate the polymorphisms of Th1 cytokine genes and their corresponding plasma cytokine levels in HIV-1 positive and exposed uninfected (EU) infants born to HIV-1 positive mothers. CD4 count, viral load of HIV-1 positive mothers was done using commercially available reagents. Cytokine genotyping analysis and levels were done in 20 HIV-1 positive and 54 EU infants. The polymorphisms of Th1 cytokines were done using the PCR-SSP method. Plasma cytokine levels were estimated using Bio-Plex-Pro cytokine assay (BIO-RAD; USA). Results revealed treatment status of the mothers and viral load were the two confounding factors having a significant effect on HIV status of the infant. TNF-α GG genotype is significantly higher in EU infants as compared with HIV-1 positive infants. GG genotype was associated with high TNF- α levels in HIV-1 positive infants but the difference was not statistically significant. HIV-1 positive infants with -IFN-γ (+874) TT genotype was significantly associated with high IFN-γ levels. To the best of our knowledge, this is the first study reporting the role of Th1 cytokine gene polymorphisms and their corresponding plasma cytokine levels in HIV-1 positive and EU infants from India.

Polymorphism of interleukin-6 -174 G/C (rs1800795) & the corresponding interleukin-6 level as a prognostic marker of cervical cancer.

BACKGROUND & OBJECTIVES: Aetiology of cervical cancer (CaCx) is multifactorial. Besides human papillomavirus (HPV) infection, many immunogenetic factors are involved in this complex process. The present study was carried out to investigate one such factor, interleukin-6 (IL-6), a central pro-inflammatory cytokine and a polymorphism at its promoter region -174 G/C (rs1800795) with CaCx. METHODS: HPV-infected women with or without CaCx were enrolled in group I and II, respectively. Another group of uninfected healthy women was also included as group III for comparison. Polymorphism in IL-6-174 G/C and IL-6 levels were analyzed by sequence-specific primer PCR (PCR-SSP) and ELISA, respectively. RESULTS: Groups I (n=111) and II (n=87) had significantly higher frequency of IL-6-174 GG genotype [odds ratios (OR)=3.9; P<0.001 and OR=3.2; P<0.001, respectively] as compared to group III (n=163). Furthermore, individuals with GG or GC genotypes had high IL-6 levels than those with CC genotypes. IL-6 levels were significantly (P<0.001) elevated in group I. This was also significantly high in untreated cases as compared to treated (P<0.05) ones. IL-6 levels of treated group were comparable with groups II and III. INTERPRETATION & CONCLUSIONS: Our results suggested a possible association of IL-6-174 GG with CaCx, which was also associated with high IL-6 levels. Decreased levels of IL-6 following treatment indicate its possible prognostic use in CaCx cases.

Human papillomavirus infection: Is it associated with epithelial ovarian cancer?

PURPOSE: Human papillomavirus (HPV), the causative agent of cervical cancer, is associated with several other epithelial malignancies. Previous reports on HPV infection and its association with ovarian cancer are highly contradicting. Reports on HPV association with ovarian cancer in Indian women are also rare. Hence, the purpose of this study was to screen women with serous epithelial ovarian cancer for possible HPV infection. METHODS: Tumor samples, collected at the time of surgery from 88 women with serous epithelial ovarian cancer were screened using a specific and sensitive PCR. The PCR results were confirmed with Southern blotting using HPV genome-specific probes, both of high-risk HPV type 16 and 18 and low-risk HPV type 6 and 11. All the samples were again tested for another 14 high-risk HPV genotypes with a commercially available qRT-PCR. RESULTS: All the samples screened and confirmed by various tests did not show presence of either low-risk or high-risk HPV DNA, indicating the absence of HPV infections in these ovarian cancer tissues. CONCLUSIONS: The present study shows that HPV infection may not be associated with epithelial ovarian cancer. The result of the current investigation strongly supports the results of earlier research that, HPV is not associated with ovarian cancer.

Anti-retroviral therapy failure in HIV-1 infected pregnant women and its associated risk of HIV transmission.

BACKGROUND: The HIV perinatal transmission in India even after interventions is still high. The anti-retroviral therapy failure rate and the risk of HIV vertical transmission to infants from women with failed treatment during pregnancy also largely remains unevaluated. METHODS: This is a prospective, observational and follow-up study of 18 months to determine the association of ART failure in pregnant women and the subsequent risk of HIV transmission to their infants. A total of 81 mothers were evaluated for ART success/failure by analysing their viral loads. RESULTS: Analyses revealed that a high percentage (19.75%) of women on ART had high viral loads, while the overall HIV transmission rate to the infants was 8.64%. The rate of transmission from women with high viral load was significantly high compared to women with low viral load (37.5% vs. 1.54%; p = 0.0015). CD4 level was not associated with HIV transmission. However, CD4 levels in women, who had successful or failed ART, were significantly different (p = 0.0031). Factors such as mother's age, baby's sex and weight as well as delivery mode were not associated with HIV transmission, however, breastfeeding and viral loads were found to be independently associated with HIV transmission to the neonates. CONCLUSIONS: This study highlights that a significant proportion of women on ART had impaired viral load control. The rate of HIV transmission to infants was also significantly high among these women. This warrants viral load monitoring of HIV infected women to reduce the overall transmission to the infants.

Distribution of human leucocyte antigen-C in HIV-1-infected patients in Mumbai, India.

HIV pathogenesis is known to be highly influenced by host genetic factors, such as human leucocyte antigens (HLAs) HLA-A and HLA-B. However, the role of HLA-C remains largely unexplored. We evaluated HLA-C distribution in 186 HIV-1-infected individuals and compared them to ethnically matched data derived from the Allele Frequency Net Database using Chi-square test with Fisher's exact two-tailed test. The frequency of HLA-C*05 and HLA-C*15 was higher in infected group, whereas the frequency of HLA-C*04 and HLA-C*14 was higher in control group. HLA-C*17, a rare allele, was significantly higher in infected group. These data could be useful in designing and testing vaccines in Indian population.

Retraction Note: Molecular mechanisms in progression of HPV-associated cervical carcinogenesis.

The Editor-in-Chief has retracted this article [1] due to significant overlap with previously published articles [2-5]. Both authors agree with this retraction.

Molecular mechanisms in progression of HPV-associated cervical carcinogenesis.

Cervical cancer is the fourth most frequent cancer in women worldwide and a major cause of mortality in developing countries. Persistent infection with high-risk human papillomavirus (HPV) is a necessary cause for the development of cervical cancer. In addition, genetic and epigenetic alterations in host cell genes are crucial for progression of cervical precancerous lesions to invasive cancer. Although much progress has been made in understanding the life cycle of HPV and it's role in the development of cervical cancer, there is still a critical need for accurate surveillance strategies and targeted therapeutic options to eradicate these cancers in patients. Given the widespread nature of HPV infection and the type specificity of currently available HPV vaccines, it is crucial that molecular details of the natural history of HPV infection as well as the biological activities of viral oncoproteins be elucidated. A better understanding of the mechanisms involved in oncogenesis can provide novel insights and opportunities for designing effective therapeutic approaches against HPV-associated malignancies. In this review, we briefly summarize epigenetic alterations and events that cause alterations in host genomes inducing cell cycle deregulation, aberrant proliferation and genomic instability contributing to tumorigenesis.

Types of human papillomavirus observed in hospital-based population.

Background and Objectives: Human papillomavirus (HPV) is the causative agent of cervical cancer, a major cause of cancer mortality in Indian women. The current study was undertaken to add information to the existing data on HPV type distribution in Indians, in an attempt to document HPV types for future vaccination programme, if any. Materials and Methods: HPV infection was screened in 223 cervical cancer cases and 2408 healthy women without cancer and cervical intraepithelial neoplasia (control). HPV was typed using polymerase chain reaction, Southern hybridisation using specific probes and HPV GenoArray (Hybribio) test. Results: HPV DNA was found in 92.8% of cases and 7.3% of controls. Of the 383 HPV-infected women, 30.0% had single infection; 50.9% had multiple infections (two or more types) and 19.1% were infected with HPV types other than HPV-16, -18, -6 and -11. Besides HPV-16, HPV-51 and HPV-33 were also seen as single infection in cases. In cases, HPV-18 or its homologous HPV-45 was always present as co-infection with HPV-16 or with other high-risk type. Binary logistic regression (backward) analysis highlighted significant association of age, parity and socioeconomic status with HPV infection. The present study highlighted the presence of multiple HPV infection (186 of 207, 89.9%) along with HPV-16 in women with cervical cancer. In control, 27.3% were co-infected with other sexually transmitted infections, while Chlamydia trachomatis infection was seen in 13% of cases. Conclusions: The study highlighted the type of HPV infection seen among the hospital-based population. For better screening, HPV tests available in the market should include all the types seen in the population.

Polymorphisms in cytotoxic T-lymphocyte associated antigen 4 gene does not affect scytotoxic T-lymphocyte associated antigen 4 levels in human papillomavirus-infected women with or without cervical cancer.

Background: Cervical cancer (CaCx) is the second most common cancer in Indian women. Cytotoxic T-lymphocyte-associated antigen 4 (CTLA-4) + 49 AA polymorphism is known to be associated with CaCx. Current attempt is to use immunotherapy for the treatment of metastatic melanoma and metastatic castration-resistant prostate cancer, i.e., blocking of CTLA-4 using a fully human monoclonal CTLA-4 antibody to disrupt its inhibitory signal. This allows the CTLs to destroy the cancer cells. There is no information available on the soluble level of CTLA-4 on which the immunotherapy is targeted. This is specifically in Indian population including cases with CaCx. Objective: The aim of this study is to evaluate the levels of soluble CTLA-4 (sCTLA-4) in human papillomavirus (HPV)-infected women with or without CaCx and their association with the polymorphism at CTLA-4 + 49 A/G and CTLA-4 -318 C/T genotypes. Materials and Methods: This is an exploratory case-control study involving two groups of HPV-infected women, the cases were with invasive CaCx and the control group was women with the healthy cervix. sCTLA-4 levels were measured using ELISA in 92 CaCx cases and 57 HPV-positive women with the healthy cervix. Results: Both cases and controls have similar sCTLA-4 levels. Comparison of CTLA-4 + 49A/G and -318 C/T genotypes with sCTLA-4 levels among cases and control also did not show any statistically significant difference. Conclusion: The present study suggests sCTLA-4 levels are not affected by a polymorphism at + 49 A>G CTLA-4. Hence, levels of CTLA-4 are similar in both CaCx cases and control group.

Human leukocyte antigen (HLA)-C and its association with HIV-1 transmission in discordant couple and mother-to-child cohorts.

Human leukocyte antigen (HLA) molecules play a key role in regulating the immune response towards infectious agents like human immunodeficiency virus type-1 (HIV-1). They have been shown to influence transmission as well as the progression of HIV-1 towards acquired immune deficiency syndrome (AIDS). Roles of HLA-A and HLA-B have been documented extensively; however, HLA-C has been poorly studied. In the present study, we have evaluated the role of HLA-C in discordant couple and mother-to-child cohorts. HLA-C*07 was higher both in HIV-1-infected spouses and infants as compared to exposed uninfected spouses and infants. However, this was not significant. HLA-C*15 was significantly higher in HIV-1-exposed uninfected babies as compared to infected babies. Lack of treatment in mothers and breastfeeding were significantly associated with HIV-1 transmission. HLA-C*07 may be a susceptible allele in HIV-1 transmission, whereas HLA-C*15 may be a protective allele in mother-to-child cohorts, independent of feeding options and treatment. These findings could be important in targeting immune responses via population-specific vaccine strategies against HIV-1.

Polymorphisms in TH1-TH2 cytokine and receptor genes associated with risk of vertical HIV transmission, in Mumbai, India.

BACKGROUND: Vertical HIV transmission does not occur in all exposed infants. Many infants remain HIV uninfected even after exposure. This is partly attributed to the host genes involving cytokine production, which is rarely documented in vertical transmission. METHODS: Here, an observational cohort study evaluated whether polymorphisms in cytokine, receptor and antagonist genes are associated with perinatal HIV transmission. Single nucleotide polymorphism (SNP) genotyping was performed via the polymerase chain reaction with sequence-specific primers method. Haplotype block structure was determined and statistical analysis was performed using appropriate software in each case. RESULTS: Twenty-two SNPs were analysed in 30 seropositive and 61 seronegative children. Confounding factors such as mother's viral load, treatment regimen, breast feeding options, etc., were documented. Analysis revealed the association of two SNPs: IL1R1 (rs2234650) and TNFA (rs1800629) with vertical HIV transmission. CT genotype at IL1R1 was observed at a higher frequency in positive children (76.66% versus 42.62%, p = 0.002), whereas the CC genotype was significantly increased in exposed uninfected children (47.54% versus 16.66%, p = 0.004). Similarly, the GG genotype of TNFA was significantly higher in uninfected children compared to infected ones (76.66% versus 46.66%, p = 0.005), whereas the GA genotype frequency was higher among infected children (53.33% versus 21.66%, p = 0.003). The frequency of the 'G' allele of TNFA and 'C' allele of IL1R1 was significant (p = 0.018) in negative children. Haplotypes of SNPs belonging to IL1, TNFA and IL4 were also found to associate with transmission. CONCLUSIONS: The present study confirms the association of SNPs IL1R1 (rs2234650) and TNFA (rs1800629) with the risk of vertical transmission. These SNPs can be exploited as possible predictive markers of HIV transmission.

Multi-centric validation of an in-house-developed beacon-based PCR diagnostic assay kit for Chlamydia and Neisseria and portable fluorescence detector.

OBJECTIVE: The development of an accurate, sensitive, specific, rapid, reproducible, stable-at-room-temperature and cost-effective diagnostic kit, and a low-cost portable fluorescence detector to fulfil the requirements of diagnostic facilities in developing countries. METHODS: We developed the 'Chlamy and Ness CT/NG kit' based on molecular beacons for the detection of Chlamydia trachomatis (CT) and Neisseriagonorrhoeae (NG). Multi-centric evaluation of the CT/NG kit was performed using the commercially available nucleic acid amplification test (NAAT)-based FTD Urethritis basic kit for comparison from December 2014 to November 2016. The stability of the kit reagents at 4 and 37 ˚C and the inter-day reproducibility of results were also analysed. RESULTS: The sensitivity and specificity of the kit were found to be 95.83 and 100.00 % for the detection of C. trachomatis and 93.24 and 99.75 % for N. gonorrhoeae, respectively, when tested against the commercial kit. The positive predictive value (PPV) was 100.00 and 98.57 %, whereas the negative predictive value (NPV) was 99.54 and 98.79 % for C. trachomatis and N. gonorrhoeae, respectively. Analysis of the kappa statistics enhanced the 'inter-rater' κ=0.976 for Chlamydia and κ=0.943 for Neisseria. CONCLUSION: Our kit was found to be as sensitive and specific as commercially available kits. Its low cost and ease of use will make it suitable for the routine diagnosis of C. trachomatis and N. gonorrhoeae in the resource-limited settings of developing countries.

Distribution of killer immunoglobulin-like receptor genes in HIV infected long-term non-progressors from Mumbai, India.

BACKGROUND: Few reports suggest the association of killer immunoglobulin-like receptors of natural killer cells with human immunodeficiency virus infection. India with world's third largest population of human immunodeficiency virus / acquired immunodeficiency syndrome, offers scope to study such association. OBJECTIVE: Current study (2010-2015) was designed to evaluate if killer immunoglobulin-like receptors gene polymorphisms are associated with HIV infection outcomes specifically, with long term non progressors. METHODS: Killer immunoglobulin-like receptors genotyping was done using polymerase chain reaction - sequence-specific primer method. Viral load was measured by Cobas Taqman HIV-1 test. Estimation of CD4 counts was done using BD FACS CD4 count reagent. RESULTS: The activating gene frequencies identified were 3DS1 (53.8%), 2DS3 (69.2%), 2DS4 (76.9%), 2DS5 (69.2%), 2DS1 (76.9%) and 2DS2 (92.3%). The inhibitory gene frequencies were 2DL2 (92.3%), 2DL5 (76.9%), 2DL3 (69.5%), 3DL1 (84.6%), 3DL2 (92.3%) and 2DL1 (100%). The results highlight high frequency of 3DS1/3DL1 heterozygote and killer immunoglobulin-like receptor 2DS1, among these long term non progressors indicating their possible association with slow progression. Genotype analysis shows total 13 genotypes, of which 8 genotypes were identified for the first time from India. Two genotypes were unique/novel, which were unreported. All genotypes observed in this study were considered to be Bx genotype (100 %). LIMITATIONS: A small sample size (n=13, due to a rare cohort) and the absence of control group were the limitations of this study. CONCLUSIONS: The present study highlights the distribution of killer immunoglobulin-like receptor genes in a very rare group of human immunodeficiency virus -1 infected individuals - long term non progressors. All the long term non progressors tested show the presence of Bx haplotype and each long term non progressors has a different killer immunoglobulin-like receptor genotype.

Diversity in KIR gene repertoire in HIV-1 exposed infected and uninfected infants: A study from India.

Natural killer (NK) cells have antiviral activity mediated through killer immunoglobulin receptors (KIRs). Studies have shown the importance of KIR receptors in HIV infection. However reports on association of KIR genes in HIV infection from Indian population are limited, not a single study is reported in HIV exposed uninfected (EU) and infected infants. This study compared the KIR gene repertoire of HIV-1 positive (n = 29) with EU (n = 76) infants to elucidate its association with transmission. KIR genotyping was analysed using the PCR-SSP method. Viral load of mothers, CD4 count of both mothers and infected infants were done using commercial kits. The data was analysed using SPSS software. Results revealed presence of significantly high frequencies of activating gene KIR 2DS5 (P = 0.040) and inhibitory gene KIR 2DL3 (P = 0.013) in EU infants as compared to HIV-1 positive infants, confirmed with multivariable linear regression modelling. Fifty-nine KIR genotypes were identified in these 105 infants. Nine genotypes were unique, reported for the first time. Twenty six genotypes were shared with the World populations. Twenty four genotypes were reported for the first time from India. Specific KIR genotype combinations (GIDs) were exclusively present either in HIV-1 positive (n = 19) or in EU infants (n = 30). The Linkage disequilibrium (LD) analysis shows a strong linkage between four pairs of genes in HIV-1 positive and three pairs of genes in EU infants. In conclusion, this study revealed that, besides maternal confounding factors such as ART and viral load, specific KIR genes are associated independently with perinatal HIV infection.