Abstract Introduction Allogeneic hematopoietic stem cell transplantation is a curative modality for aplastic anemia; the preferred stem cell source is bone marrow. However, allogeneic peripheral ...blood stem cell transplantation (PBSCT) used in high-risk patients is associated with higher risk of chronic graft-versus-host disease (GVHD). Our center receives multitransfused, alloimmunized, infected, late referrals for transplant. Methods Forty-one patients of median age 22 years (range 8–37) received allogeneic-PBSCT from human leukocyte antigen (HLA)-matched sibling donors. The median time since diagnosis was 12 months (range 4–65) and median pretransplant transfusions were 37 (range 6–160). Six patients were platelet refractory and one alloimmunized for pan-red blood cell (RBC) antigens. Several patients had pretransplant icterus or renal dysfunction and 26 (63.4%) had unresponsive bacterial/fungal infections. Our conditioning regimen included fludarabine 30 mg/m2 for 6 days (days –10 to –5), cyclophosphamide 60 mg/kg/d for 2 days (days –6 to –5), and antithymocyte globulin (ATGAM) 30 mg/kg/d for 4 days (day –4 to –1), which was reduced to 2 days in 2 patients. We used standard GVHD prophylaxis with cyclosporine and methotrexate on days 1, 3, 6, 11. Results The median follow-up period was 29 months (range 6–78) and median engraftment time 10 days (range 8–17). Thirty-one patients (75.6%) were treated for infections, with 20 of these on antifungals for preexisting infections. There were two graft rejections and 10 (24.4%) deaths, with three intracranial hemorrhages, two rejections with infection, three cases of refractory GVHD (acute/overlap syndrome) with cytomegalovirus reactivation, and two invasive fungal infections. Overall incidence of acute GVHD was 39% with 2 grade IV cases. Ten (25%) cases developed chronic GVHD, with extensive GVHD in four. Conclusion With more experience using shortened course of ATGAM, HLA-matched donor transfusions, and availability of newer antifungals, we have been able to decrease PBSCT-related mortality. Further improvement will be possible with early referrals.
Summary
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.
Summary
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.
Abstract 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.
We present here the results of the Analysis of HLA Population Data (AHPD) project of the 16th International HLA and Immunogenetics Workshop (16IHIW) held in Liverpool in May-June 2012. Thanks to the ...collaboration of 25 laboratories from 18 different countries, HLA genotypic data for 59 new population samples (either well-defined populations or donor registry samples) were gathered and 55 were analysed statistically following HLA-NET recommendations. The new data included, among others, large sets of well-defined populations from north-east Europe and West Asia, as well as many donor registry data from European countries. The Generate computer tools were combined to create a Generate computer pipeline to automatically (i) estimate allele frequencies by an expectation-maximization algorithm accommodating ambiguities, (ii) estimate heterozygosity, (iii) test for Hardy-Weinberg equilibrium (HWE), (iv) test for selective neutrality, (v) generate frequency graphs and summary statistics for each sample at each locus and (vi) plot multidimensional scaling (MDS) analyses comparing the new samples with previous IHIW data. Intrapopulation analyses show that HWE is rarely rejected, while neutrality tests often indicate a significant excess of heterozygotes compared with neutral expectations. The comparison of the 16IHIW AHPD data with data collected during previous workshops (12th-15th) shows that geography is an excellent predictor of HLA genetic differentiations for HLA-A, -B and -DRB1 loci but not for HLA-DQ, whose patterns are probably more influenced by natural selection. In Europe, HLA genetic variation clearly follows a north to south-east axis despite a low level of differentiation between European, North African and West Asian populations. Pacific populations are genetically close to Austronesian-speaking South-East Asian and Taiwanese populations, in agreement with current theories on the peopling of Oceania. Thanks to this project, HLA genetic variation is more clearly defined worldwide and better interpreted in relation to human peopling history and HLA molecular evolution.
Summary
We present here the results of the Analysis of HLA Population Data (AHPD) project of the 16th International HLA and Immunogenetics Workshop (16IHIW) held in Liverpool in May–June 2012. Thanks ...to the collaboration of 25 laboratories from 18 different countries, HLA genotypic data for 59 new population samples (either well‐defined populations or donor registry samples) were gathered and 55 were analysed statistically following HLA‐NET recommendations. The new data included, among others, large sets of well‐defined populations from north‐east Europe and West Asia, as well as many donor registry data from European countries. The Generate computer tools were combined to create a Generate computer pipeline to automatically (i) estimate allele frequencies by an expectation‐maximization algorithm accommodating ambiguities, (ii) estimate heterozygosity, (iii) test for Hardy–Weinberg equilibrium (HWE), (iv) test for selective neutrality, (v) generate frequency graphs and summary statistics for each sample at each locus and (vi) plot multidimensional scaling (MDS) analyses comparing the new samples with previous IHIW data. Intrapopulation analyses show that HWE is rarely rejected, while neutrality tests often indicate a significant excess of heterozygotes compared with neutral expectations. The comparison of the 16IHIW AHPD data with data collected during previous workshops (12th–15th) shows that geography is an excellent predictor of HLA genetic differentiations for HLA‐A, ‐B and ‐DRB1 loci but not for HLA‐DQ, whose patterns are probably more influenced by natural selection. In Europe, HLA genetic variation clearly follows a north to south‐east axis despite a low level of differentiation between European, North African and West Asian populations. Pacific populations are genetically close to Austronesian‐speaking South‐East Asian and Taiwanese populations, in agreement with current theories on the peopling of Oceania. Thanks to this project, HLA genetic variation is more clearly defined worldwide and better interpreted in relation to human peopling history and HLA molecular evolution.
: The HLA class II molecules play a critical role in the processing and presentation of specific peptides derived from autoantigens of pancreatic beta cells or gluten for T cell scrutiny in IDDM and ...CD. In the present study, extended DR3‐positive haplotypes associated with autoimmunity in northern Indian patients have been reported. The haplotype A26‐B8‐DR3 was the most common autoimmunity‐favoring haplotype encountered among these patients. This association is, indeed, unique to Indian autoimmune patients, as it replaces the otherwise most commonly associated Caucasian haplotype A1‐B8‐DR3 (AH8.1) in this population. Further, CD patients revealed 100% association with DQB1*0201 along with DQA*0501 (97%) either in cis or trans configuration.
Abstract A major limitation in hematopoietic stem cell transplantation (HSCT) is the availability of a genetically matched donor, particularly with respect to the human leukocyte antigens ...(HLA)–linked immune response genes located on chromosome 6 in humans. During the last 5 years, a total of 688 patients requiring HSCT underwent HLA testing in our department to identify a matched donor from their families. The sibship size ranged from 1 to ≥5 in all disease categories, except thalassemia major where the majority of patients had only 1 sibling. Family genotype analysis revealed that 39.3% of the total number of patients had an HLA-matched sibling and that families with sibship size of ≥4 had a higher probability (68.8%) compared with those with sibship size of ≤3 (29.7%). Because the Indian population is characterized by the presence of novel HLA alleles and unique haplotypes (HLA-A*0211, B*2707, A*26-B*08-DRB1*03), patients with rare HLA alleles have much less probability of finding an unrelated optimally matched donor than those with common HLA phenotypes. Smaller family size and unique HLA profile are limitations that can be overcome by developing unrelated volunteer marrow donor registries. The Asian Indian Donor Marrow Registry at our institute is regularly providing services to such patients.
