Effect of fetal liver condition media derived cytokines(IL-6 and Flt-3) on human bone marrow stem cells colony formation.

Earlier research from our laboratory demonstrated the presence of stimulatory activity of different growth factors in the fetal liver (FL) extracts when collected in a medium known as fetal liver conditioned medium (FLCM) using Enzyme-linked Immunosorbent Assay (ELISA). In the present study, we have assessed two other cytokines viz. IL-6 and FMS like tyrosine kinase-3 (Flt-3) with the help of bioneutralization assay. FLCM was prepared by incubating fetal liver cells with Iscove's Modified Dulbecco's Medium (IMDM) containing 10% fetal bovine serum (FBS) and 10% Phytohemagglutinin and collected after 24hrs, 48hrs, 72 hrs. and on the 7th day of incubation. Clonal cultures were established for 1 X 105 normal bone marrow (BM) mononuclear cells (NBM MNC) per plate with methylcellulose medium containing cytokines SCF and EPO. Mean Colony forming units-granulocytes, erythrocytes, macrophages, megakaryocytes (CFU-GEMM) were assessed with and without the addition of FLCM. It was found that FLCM enhanced the number of colonies made by NBM MNCs. Further, cytokines IL-6 and Flt-3, present in FLCM, were bioneutralized with respective anti-cytokine antibodies. Neutralized FLCM was evaluated for the colony-forming potential of CFU-GEMM colonies. The maximum reduction of 42% was seen with 20 ng/ml of anti-IL-6 antibody. Maximum suppression up to 20% was observed with 0.7 ng/ml of anti Flt-3 antibody for CFU-GEMM colonies. Presence of cytokines IL-6 and Flt-3 in FL extracts and their colony stimulatory activity suggests that fetal liver infusion (FLI) may be a valuable alternative for managing BM recovery in certain clinical conditions such as AA.

In vitro expansion of fetal liver hematopoietic stem cells.

Fetal liver hematopoietic stem and progenitor cells (HSPCs) have been considered appropriate for the management of aplastic anemia owing to their proliferative potential. Bone marrow recovery was possible in some cases; the engraftment potential of these cells, however was unsatisfactory, possibly due to the availability of a smaller number of these cells from a single fetus. The present study explores how we can expand fetal liver hematopoietic stem cells under in vitro conditions. We isolated mononuclear cells from fetal liver and hematopoietic stem cells were identified and analyzed by cell surface marker CD34. CD34+ fetal liver HSPCs cells were separated by magnetic cell sorting positive selection method. HSPCs (CD34+) were cultured by using 5 cytokines, stem cell factor (SCF), granulocyte macrophages-colony stimulating factor (GM-CSF), interleukin-6 (IL-6), Fms-related tyrosine kinase 3 (FLT-3) and erythropoietin (EPO), in 4 different combinations along with supplements, in serum-free culture media for 21 days. Cell viability continued to be greater than 90% throughout 21 days of culture. The cells expanded best in a combination of media, supplements and 5 cytokines, namely SCF, FLT-3, IL6, EPO and GM-CSF to yield a large number of total (CD34+ & CD34-) cells. Even though the total number of nucleated cells increased in culture significantly, levels of CD34 antigen expression declined steadily over this period.

Clinical and immunological relevance of antibodies in solid organ transplantation.

The two important issues affecting recipients of solid organ transplants and of importance to immunologists are (i) sensitization of the recipient to HLA antigens and the resultant humoral immune response leading to the development of anti-HLA antibodies; and ii) development of robust assays for early detection of humoral rejection post-transplant. Evidence from several studies clearly indicates that presence of circulating anti-HLA antibodies especially donor specific leads to early graft loss and high titres of DSA may even lead to hyperacute or accelerated acute rejection. Long-term graft survival too is adversely affected by the presence of either pre- or post-transplant DSA. HLA matching status of the recipient - donor pair - is an important factor in the modulation of humoral response following transplantation and in a way affects de novo development of DSA. Data collected over the past decade clearly indicate significantly lower level of DSAs in optimally matched donor-recipient pairs. HLA mismatches especially those on HLA-DR and HLA-C loci have wider implications on post-transplant graft survival. The presence of circulating anti-HLA antibodies leads to endothelial damage in the newly grafted organ through complement dependent or independent pathways. Although detection of C4d deposition in renal biopsies serves as an important indicator of humoral rejection, its absence does not preclude the presence of DSAs and humoral rejection, and hence, it cannot be relied upon in every case. The emergence of epitope-based screening for anti-HLA antibodies on Luminex platform with high degree of sensitivity has revolutionized the screening for anti-HLA antibodies and DSAs. Studies indicate that humoral response to non-HLA antigens might also have a detrimental effect on allograft survival. High titres of such circulating antibodies may even lead to hyperacute rejection. Pre-emptive testing of solid organ recipients, especially kidney transplant recipients for anti-HLA and non-HLA antibodies and aggressive post-transplant monitoring of allograft function to detect DSAs using Luminex-based tests, is highly recommended.

CTLA4+49G allele associates with early onset of type 1 diabetes in North Indians.

Type 1 diabetes (T1D) is a complex autoimmune disease with strong genetic influence. In this study, we investigated +49A/G SNP (rs 231775) in exon 1 of cytotoxic T-lymphocyte-associated antigen 4 (CTLA4) by PCR-RFLP and its influence as a risk factor for the disease in the North Indian population. This polymorphism at codon 17 results in an amino acid substitution (Thr/Ala) in the leader peptide of the molecule. The study included 232 patients with T1D (age at onset of disease (AOD): 0.5-37 years) and 305 ethnically matched healthy controls. The DNA obtained from these 537 individuals was amplified using a set of specific primers followed by restriction enzyme digestion with Fnu4HI. The +49G allele as well as its homozygous genotype G/G was observed to be significantly higher in patients as compared to the healthy controls {(37.3% vs. 25.6%, P = 4.96E(-05) , OR = 1.73; 95%CI = 1.33-2.25) (15.52% vs. 6.6%, P = 0.001, OR = 2.62; 95% CI = 1.48-4.63) respectively}. The frequency of G/G genotype was significantly higher in patients with early age at onset of disease (AOD:<12 years) as compared to that in the late-onset patients with AOD: ≥12 years (21.1% vs. 10.6%, P = 0.042, OR = 2.26; 95% CI = 1.09-4.67) as well as to that in the healthy controls (21.1% vs. 6.6%, P = 0.00004, OR = 3.8; 95% CI = 2.01-7.2). Further analysis revealed that the median AOD significantly reduced (P = 0.049) from 14 years in patients with A/A genotype to 11 and 10 years in those with A/G and G/G genotypes, respectively. These results suggest that CTLA4+49G allele, particularly in homozygous G/G condition, associates with early onset of T1D.

Association of PTPN22+1858C/T polymorphism with Type 1 diabetes in the North Indian population.

A nonsynonymous SNP +1858C/T (rs2476601) in the protein tyrosine phosphatase, nonreceptor type 22(PTPN22) gene leading to Arg 620 Trp substitution is known to be associated with susceptibility to type 1 diabetes (T1D) and several other autoimmune diseases. We studied this polymorphism in 145 T1D patients and 210 healthy controls from North India. The minor allele +1858T was observed to be significantly increased among patients as compared to healthy controls (2.76% vs 0.5%, P = 0.027, OR = 5.93; 95% CI = 1.4-24.8). The association was also observed at the level of heterozygous C/T genotype (5.5% vs 0.95%, P = 0.026, OR = 6.07; 95% CI = 1.43-25.6). The T allele and C/T genotype were predominantly found among patients who were positive for both glutamic acid decarboxylase 65 (GAD65) and insulin antigen 2 (IA2) autoantibodies and showed significantly increased frequencies (10%, P = 0.034, OR = 11.67; 95% CI = 1.58-84.1 and 20%, P = 0.031, OR = 13.0; 95% CI = 1.66-97.5, respectively) as compared to patients negative for these autoantibodies (0.95% and 1.9%, respectively). The results suggest that the PTPN22+1858T allele is positively associated with T1D in the North Indian population.

The short-term impact of protocol biopsies in a live-related renal transplant program using tacrolimus based immunosuppression.

The aim of the study was to assess the impact of protocol biopsies in a live-related renal transplant program using tacrolimus-based immunosuppression in the short term. Eighty-three live-related transplant recipients were randomly allocated to protocol biopsy group (Group I, n = 40) and a control group (Group II, n = 43). Other immunosuppressants in these groups consisted of either mycophenolate mofetil or azathioprine and steroids. Protocol biopsies were conducted in biopsy group at 1, 6, and 12 months post-transplant. The non-biopsy group was followed by serial serum creatinine and biopsies in them were conducted as and when clinically indicated. Both groups were analyzed at 12 months with respect to graft function and survival. The two groups were similar with respect to age, number of dialysis pre-operatively, tacrolimus levels, induction therapy, donor age, and donor glomerular filtration rate. Forty protocol biopsies were conducted at 1 month, 31 at 6 months, and 26 at 12 months. The prevalence of sub-clinical rejection at 1, 6, and 12 months in these biopsies was 17.5%, 11.2%, and 10.3%, respectively. The prevalence of calcineurin inhibitor toxicity during same period was 15%, 15.5%, and 14.4%, respectively. The cumulative rejection rate in Group I and Group II at 12-month follow-up was 10.3% and 11.3% (P = 0.78), respectively, and cumulative calcineurin inhibitor toxicity at 12 months was 14.4% and 9.3% (P = 0.59), respectively, were not statistically significant. There was no difference in graft survival and function at 1 year. Protocol biopsies have a limited role in a well-matched renal transplant program with tacrolimus-based immunosuppression in the short term. However, the long-term impact of protocol biopsies needs further evaluation.

Role of killer immunoglobulin-like receptor-ligand interactions in human leukocyte antigen-matched sibling hematopoietic stem cell transplantation.

INTRODUCTION: Killer immunoglobulin-like receptor (KIR)-ligand mismatches lead to natural killer cell alloreactivity after hematopoietic stem cell transplantation (HSCT). However, their clinical impact on HSCT outcomes is controversial due to complexity of KIR haplotypes, genotypes, and phenotypes as well as their diversity among patient populations. The present study investigated the role of KIR-ligand interactions in human leukocyte antigen (HLA)-matched sibling transplants. METHODS: The recipient cohort, which included patients diagnosed with aplastic anemia, acute leukemia, and myelodysplastic syndrome, received granulocyte-colony stimulating factor (G-CSF)-mobilized peripheral blood stem cells. HLA typing was performed using polymerase chain reaction - sequence specific oligo probes (PCR-SSO). The KIR genotype of the donors and the ligands C1 (Asparagine 80), C2 (Lysine 80), and Bw4 recipient typings were performed using polymerase chain reaction - sequence specific primers (PCR-SSP). We assessed acute and chronic graft-versus-host disease (GVHD), relapse, and overall survival. RESULTS: While 84.5% of donors carried a Bx KIR, 15.5% carried the AA haplotype. The effect of a recipient's lack of ligands among 88.5% of cases was associated with 39% of subjects developing GvHD. Lack of C1 may lead to manifestations of acute GvHD and lack of C2 to manifestation of chronic GvHD. The presence of both C1 and C2 seemed to be protective against both forms of GvHD. The role of two Bw4 alleles, threonine (T) or isoleucine (I) at position 80, was evaluated. 73% of recipients who carried Bw4 80(I) versus 27% with the Bw4 80(T) allele. The presence of Bw4-80(T) allele appeared to reduce the risk of GvHD, indicating its stronger inhibitory effect than its 80(I) counterpart. CONCLUSION: KIR-ligand interactions influenced HSCT outcomes.

Prevalence of smear-positive pulmonary tuberculosis in different ethnic groups in India: evaluation of public health.

OBJECTIVE: To estimate the prevalence of pulmonary tuberculosis (TB) in a high-risk rural area of central India. STUDY DESIGN: Retrospective analysis of primary data. METHODS: In total, 10,963 sputum smears were screened from Hindu tribes (n = 4032), Hindu non-tribal (n = 5445) and Muslim communities (n = 1486) between 2004 and 2009. Smears were recorded as positive or negative for tubercle bacilli following staining with acid-fast bacilli, in accordance with the guidelines of the World Health Organization. Age- and gender-specific prevalence rates and relative risks (RR) were calculated using Statistical Package for the Social Sciences Version 13.0. RESULTS: The prevalence of TB was found to be significantly higher in Hindu tribes compared with Hindu castes and Muslims (P < 0.005). The overall RR of developing smear-positive disease was 1.4-fold higher (95% confidence interval 1.1-1.7; P < 0.005) in males than females in all the study groups. The highest prevalence of TB was observed in subjects aged 15-34 years. CONCLUSIONS: Hindu tribes and males of working age are still at high risk of smear-positive TB.

A low frequency variant within the GWAS locus of MTNR1B affects fasting glucose concentrations: genetic risk is modulated by obesity.

Two common variants (rs1387153, rs10830963) in MTNR1B have been reported to have independent effects on fasting blood glucose (FBG) levels with increased risk to type 2 diabetes (T2D) in recent genome-wide association studies (GWAS). In this investigation, we report the association of these two variants, and an additional variant (rs1374645) within the GWAS locus of MTNR1B with FBG, 2h glucose, insulin resistance (HOMA IR), ß-cell function (HOMA B), and T2D in our sample of Asian Sikhs from India. Our cohort comprised 2222 subjects [1201 T2D, 1021 controls]. None of these SNPs was associated with T2D in this cohort. Our data also could not confirm association of rs1387153 and rs10830963 with FBG phenotype. However, upon stratifying data according to body mass index (BMI) (low ≤ 25 kg/m(2) and high > 25 kg/m(2)) in normoglycemic subjects (n = 1021), the rs1374645 revealed a strong association with low FBG levels in low BMI group (ß = -0.073, p = 0.002, Bonferroni p = 0.01) compared to the high BMI group (ß = 0.015, p = 0.50). We also detected a strong evidence of interaction between rs1374645 and BMI with respect to FBG levels (p = 0.002). Our data provide new information about the significant impact of another MTNR1B variant on FBG levels that appears to be modulated by BMI. Future confirmation on independent datasets and functional studies will be required to define the role of this variant in fasting glucose variation.

A novel HLA-DPB1 allele, DPB1*125:01, identified by sequence-based typing in an Indian individual.

A novel DPB1*125:01 allele differs from DPB1*26:01:02 at two positions in exon 2, leading to changes at codons 9 and 35.

Outcome of pediatric renal transplantation in north India.

We report our experience and long-term outcome of pediatric renal transplantation at a referral center in New Delhi. During 1995-2008, 45 transplants were performed in 43 patients at a mean age of 13.3 ± 4.0 (range 3.8-18) yr. The chief causes for ESRD were reflux nephropathy, obstructive uropathy, vasculitis, renal dysplasia, and focal segmental glomerulosclerosis. Most (91.1%) donors were living related. Post-transplant immunosuppression comprised prednisolone, a calcineurin inhibitor and azathioprine or MMF. AR and CR were seen in 14 (31.1%) and 12 (26.7%) allografts, respectively. Predictors of CR were unsatisfactory compliance and multiple episodes of AR (p = 0.002 each). Urinary infections (n = 13), septicemia (4), tuberculosis (4), CMV disease (7), viral hepatitis (7), and pneumonia (3) were important causes of morbidity. Two patients each had lymphoproliferative disease and new-onset diabetes. There were eight (17.8%) graft losses and six (14%) deaths. The one-, five- and 10-yr graft survivals were 91.1%, 80.4% and 75.1%, respectively; the mean graft survival was 119.4 ± 8.38 months. The respective patient survivals were 95.3%, 87.9%, and 76.9% at one-, five- and 10 yr. Our results affirm that despite scarcity of resources and frequent infections, long-term outcomes of pediatric renal transplantation are highly satisfactory.

Human Toll-like receptor 4 polymorphisms TLR4 Asp299Gly and Thr399Ile influence susceptibility and severity of pulmonary tuberculosis in the Asian Indian population.

Genetic polymorphisms in Toll-like receptor 4, TLR4 896 A/G (Asp299Gly) and 1196 C/T (Thr399Ile) have been reported to influence TLR4 function and the innate host immune response to mycobacteria. We investigated the effect of these single nucleotide polymorphisms on susceptibility and severity of pulmonary tuberculosis (PTB) in the Asian Indian population. A significantly increased frequency of TLR4 Asp299Gly mutation was observed in the patient group (17%) as compared with healthy controls [8.8%, chi(2) = 10.7, P = 0.001,odds ratio (OR ) = 2.1]. On the other hand, the TLR4 Thr399Ile mutation occurred with comparable frequencies in the two groups (12.6% among patients and 9% in healthy controls). The PTB patients were categorized on the basis of their bacillary load as 3+, 2+, 1+, negative and on the extent of lung involvement as having minimal, moderate, and far-advanced lung disease. The 299Gly mutant occurred in homozygous state (GG) only in patients with high bacillary load (3+) and those with far-advanced lung disease. Similarly, the mutant 399Ile was significantly pronounced in these patients in the homozygous state (TT). The present data suggest that TLR4 substitutions at residues 299 and 399 are associated with pulmonary TB, particularly, the most severe disease.

Allotyping human complement factor B in Asian Indian type 1 diabetic patients.

Human complement factor B (BF) is an essential component of the alternate complement pathway and therefore important in innate immune and autoimmune responses. The BF gene is located in the central region of major histocompatibility complex (MHC) and is known to encode more than 30 protein variants that can be resolved by isoelectric focusing and gel electrophoresis. There are three BF alleles - BF*S, BF*FB and BF*FA - that differ in codon 7 at nucleotide positions 94 and 95. These alleles have CGG, TGG or CAG triplets at their codon 7, respectively, that code for Arg, Trp or Gln residues. We have developed a novel polymerase chain reaction using sequence-specific primers-based allotyping assay that can identify nucleotide substitutions in codon 7 in all the three BF alleles. The assay was validated by sequencing and amplified fragment length polymorphism. Using this SSP assay, we report the BF alleles located on the multiple human leukocyte antigen (HLA)-DR3 haplotypes that are unique in the Indian population and are associated with autoimmunity. The common type 1 diabetes (T1D)-favoring Caucasian haplotype HLA-A1-B8-DR3 (ancestral haplotype AH8.1) carries BF*S. However, in the North Indian T1D patients, the most common haplotype is HLA-A26-B8-DR3 (AH8.2) and this carried BF*FB. Because of its association with AH8.2, the BF*FB was overrepresented in the patients (51.03%) compared with healthy controls (32.7%, OR = 2.148, 95% CI = 1.34-3.44, P = 0.002). Similar studies on allotyping BF alleles in different haplotypes in various populations could have important implications in understanding mechanisms of MHC haplotypic diversifications and disease associations and designing future therapeutic approaches.

TCF7L2 polymorphisms are associated with type 2 diabetes in Khatri Sikhs from North India: genetic variation affects lipid levels.

Recently, the transcription factor-7-like 2 (TCF7L2) gene has been identified as the most important type 2 diabetes mellitus (T2DM) susceptibility gene. Common intronic polymorphisms in this gene have been found to be strongly associated with T2DM susceptibility showing marked reproducibility in multiple populations. The purpose of this study was to confirm the reported association of six TCF7L2 variants in a Khatri Sikh diabetic sample from North India. We genotyped six-associated SNPs in a case-control sample consisting of 556 T2DM cases and 537 controls. We also examined the impact of these variants on body mass index (BMI), waist to hip ratio (WHR), fasting insulin, and glucose and lipid levels. We report replication of association of four of the six SNPs with T2DM in this Khatri Sikh sample [rs7903146, (p = 0.010); rs11196205, (p = 0.011); rs10885409, (p = 0.002) and rs4918789, (p = 0.029)], under a dominant model conferring odds ratios (ORs) of 1.39, 1.44, 1.57 and 1.36, respectively. Haplotype analysis provided further evidence of association by showing a significant difference between cases and controls as revealed by the global omnibus test (chi(2)= 19.36; p = 0.0036). Multiple linear regression analysis also revealed the risk allele carriers of three of four significant SNPs (rs7903146, rs11196205, rs10885409) to be significantly associated with increased fasting total cholesterol (p value = 0.019, 0.025, 0.006) and LDL cholesterol levels (p value = 0.021, 0.018, 0.005), respectively. Our findings confirm that the TCF7L2 gene is a major risk factor for development of T2DM in Khatri Sikhs. It also provides new information about the significant impact of TCF7L2 gene variants on plasma cholesterol levels that appear to be independent of BMI.

Assessment of fetomaternal hemorrhage by flow cytometry and Kleihauer-Betke test in Rh-negative pregnancies.

OBJECTIVES: To assess the efficacy of flow cytometry (FC) in the detection and quantification of fetomaternal hemorrhage (FMH) in comparison to the Kleihauer-Betke test (KBT). METHODS: 25 unsensitized Rh-negative mothers who had delivered Rh-positive infants were included. Presence of FMH was determined by KBT and FC using FITC-labeled BRAD-3 antibodies. RESULTS: FMH was detected in 19 (76%) patients by FC and 23 (92%) patients by KBT prior to delivery, and in 21 (84%) patients by FC and 23 (92%) patients by KBT after delivery. The mean volume of FMH in the post-delivery samples by KBT and FC were 0.34 +/- 0.26 ml (range 0.05-1.2 ml) and 0.37 +/- 0.57 ml (range 0.02-2.6 ml) respectively. The volume of post-delivery FMH estimated by KBT and FC correlated well (r = 0.75; ICC alpha = 0.73). A higher agreement between KBT and FC was seen in the 0.1-0.5 ml range (kappa = 0.65; p < 0.01). CONCLUSIONS: Both manual KBT and FC using FITC-BRAD-3 antibodies show good sensitivity in detecting and quantifying fetal red cells. There is a good correlation between the methods in the 0.1- to 0.5-ml range of FMH.

Distribution of CCR2 polymorphism in HIV-1-infected and healthy subjects in North India.

Substitution of V64I in CCR2 relates to delayed progression to AIDS and protects against HIV-1 infection. We examined the distribution of V64I in HIV-infected and healthy North Indian subjects. No significant difference in the allele or genotype distribution of CCR2 V64I polymorphism was observed, indicating that there is no association between CCR2 V64I polymorphism and susceptibility to HIV infection in North Indian population.

14th International HLA and Immunogenetics Workshop: report on joint study on MHC and infection.

The 'MHC and Infection' study of the 14th International HLA and Immunogenetics Workshop was undertaken to evaluate the contribution of specific variants of major histocompatibility complex (MHC) and non-MHC genes that are specifically associated with higher probabilities of infection, disease severity, and progression in different populations.

Immunogenetics of mycobacterial infections in the North Indian population.

Several lines of evidence highlight the genetic basis of risk to develop mycobacterial diseases. Human leukocyte antigen (HLA)-DR2 alleles (DRB1*1501 and DRB1*1502) have been found to be strongly associated with mycobacterial disease, especially the more severe forms such as lepromatous leprosy and multidrug-resistant pulmonary tuberculosis. In this study, DNA-based high-resolution typing techniques of polymerase chain reaction-sequence-specific oligonucleotide probe were used to determine the distribution of HLA-DR/DQ alleles in patients with leprosy and pulmonary tuberculosis. Analysis of different DR2 subtypes based on valine/glycine dimorphism at codon beta86 in pocket 1 of HLA-DR showed an inverse relationship of DR2 alleles with V/G as the severity of disease increased both in leprosy and in pulmonary tuberculosis.

Association of variants in the IL12B gene with leprosy and tuberculosis.

There is a great range in outcomes after mycobacterial infections, and this is probably due to individual variation in immune responses. One of the key cytokine regulators of the immune response is interleukin (IL-) 12. The IL12B gene encodes the p40 chain of both IL-12 and IL-23 and it has two major variant sites at which different alleles are associated with increased levels of gene expression and with susceptibility to a range of immune-related diseases. We hypothesized that IL12B variants associated with increased expression would be as associated with susceptibility to persistent mycobacterial infection. We tested this hypothesis by genotyping Indian subjects, having either leprosy or tuberculosis (TB), as well as ethnically matched controls. Subjects with leprosy were less likely to have the 3'UTR genotype associated with lower IL12B expression (P= 0.001). Subjects with TB were not only more likely to have the high-expressing IL12B promoter genotype (P= 0.01) but also more likely to have this in the same haplotype with the high expressing 3'UTR allele (P= 0.0009). These results suggest these infectious diseases may be improved by modulating IL-l2p40 production.