Major histocompatibility complex (MHC) antigens polymorphism and alloimmunization study in thalassemia patients with febrile non-hemolytic transfusion reaction (FNHTR).

OBJECTIVES: HLA alloimmunization is one of the most troublesome consequence of regular transfusion which is itself a mainstay measure to provide longevity to the thalassemia patients. Febrile non-hemolytic transfusion reaction (FNHTR) is one of the most common complication which might be related to the HLA alloimmunization. Here, we studied the HLA antigenic system and alloimmunization rate in the Iranian ß-thalassemia patients who suffered from FNHTR compare to the ß-thalassemia patients without FNHTR. MATERIALS & METHODS: Total of 60 ß-thalassemia patients with FNHTR (case group) and 20 ß-thalassemia patients without FNHTR (control group) randomly have been selected and enrolled in the study. All were tested for HLA-A and -B loci by PCR-SSP method and also for the presence of anti-lymphocyte antibodies by LIFT method. Comparisons between two groups were performed by Pearson's χ2 test. RESULTS: Totally, a significant predominance was noted for two HLA alleles, HLA-A*24 (P = 0.029) and B*55 (P = 0.034) which have higher prevalence in control group. Although no significant association was found between the presence of anti-leukocyte antibodies and the development of FNHTR, the HLA-A*32 (P = 0.047) allele was considered as possible genetic markers in the susceptibility to the development of anti-leukocyte antibodies. CONCLUSION: Here some evidences about the possible role of HLA polymorphism in susceptibility to FNHTR are provided. Those results indicated that HLA-A*24 and HLA-B*55 might play protective role on inducing FNHTR in ß-thalassemia patients. Further studies which investigate the allele level of HLA-I alongside with specific reactivity of HLA-I antibodies might reveal more deep data about these phenomena.

Signaling factors potentially associated to the pathogenesis of Adult T-cell leukemia /lymphoma: A network-analysis and novel findings assessment.

Adult T-cell leukemia/lymphoma (ATLL) is a human T-cell leukemia virus (HTLV) type 1-associated disease of TCD4+ cell transformation. Despite extensive studies on ATLL development and progression, the fundamental processes of HTLV-1 oncogenicity are yet to be understood. This study aimed to integrate high-throughput microarray datasets to find novel genes involved in the mechanism of ATLL progression. For this purpose, five microarray datasets were downloaded from the Gene Expression Omnibus database and then profoundly analyzed. Differentially expressed genes and miRNAs were determined using the MetaDE package in the R software and the GEO2R web tool. The STRING database was utilized to construct the protein-protein interaction network and explore hub genes. Gene ontology and pathway enrichment analysis were carried out by employing the EnrichR web tool. Furthermore, flow cytometry was employed to assess the CD4/CD8 ratio, and quantitative reverse transcription-polymerase chain reaction (qRT-PCR) was used to confirm the high-throughput data analysis results. Four miRNAs, including hsa-mir-146, hsa-mir-451, hsa-mir-31, and hsa-mir-125, were among the statistically significant differentially expressed miRNAs between healthy individuals and ATLL patients. Moreover, 924 differentially expressed genes were identified between normal and ATLL samples. Further network analysis highlighted 59 hub genes mainly regulating pathways implicated in viral interferences, immunological processes, cancer, and apoptosis pathways. Among the identified hub genes, RhoA and PRKACB were most considerable in the high-throughput analysis and were further validated by qRT-PCR. The RhoA and PRKACB expression were significantly down-regulated in ATLL patients compared to asymptomatic carriers (p<0.0001 and p=0.004) and healthy subjects (p=0.043 and p=0.002). Therefore, these corresponding miRNAs and proteins could be targeted for diagnosis purposes and designing effective treatments.

Comprehensive high-throughput meta-analysis of differentially expressed microRNAs in transcriptomic datasets reveals significant disruption of MAPK/JNK signal transduction pathway in Adult T-cell leukemia/lymphoma.

BACKGROUND: Human T-lymphotropic virus 1 (HTLV-1) infection may lead to the development of Adult T-cell leukemia/lymphoma (ATLL). To further elucidate the pathophysiology of this aggressive CD4+ T-cell malignancy, we have performed an integrated systems biology approach to analyze previous transcriptome datasets focusing on differentially expressed miRNAs (DEMs) in peripheral blood of ATLL patients. METHODS: Datasets GSE28626, GSE31629, GSE11577 were used to identify ATLL-specific DEM signatures. The target genes of each identified miRNA were obtained to construct a protein-protein interactions network using STRING database. The target gene hubs were subjected to further analysis to demonstrate significantly enriched gene ontology terms and signaling pathways. Quantitative reverse transcription Polymerase Chain Reaction (RTqPCR) was performed on major genes in certain pathways identified by network analysis to highlight gene expression alterations. RESULTS: High-throughput in silico analysis revealed 9 DEMs hsa-let-7a, hsa-let-7g, hsa-mir-181b, hsa-mir-26b, hsa-mir-30c, hsa-mir-186, hsa-mir-10a, hsa-mir-30b, and hsa-let-7f between ATLL patients and healthy donors. Further analysis revealed the first 5 of DEMs were directly associated with previously identified pathways in the pathogenesis of HTLV-1. Network analysis demonstrated the involvement of target gene hubs in several signaling cascades, mainly in the MAPK pathway. RT-qPCR on human ATLL samples showed significant upregulation of EVI1, MKP1, PTPRR, and JNK gene vs healthy donors in MAPK/JNK pathway. DISCUSSION: The results highlighted the functional impact of a subset dysregulated microRNAs in ATLL on cellular gene expression and signal transduction pathways. Further studies are needed to identify novel biomarkers to obtain a comprehensive mapping of deregulated biological pathways in ATLL.

The impact of donor and recipient KIR genes and KIR ligands on the occurrence of acute graft-versus-host disease and graft survival after HLA-identical sibling hematopoietic stem cell transplantation

Background/aim: After allogeneic hematopoietic stem cell transplantation (allo-HSCT), donor natural killer (NK) cells trigger alloreactions against potential recipient cells by their killer immunoglobulin-like receptors (KIRs). This study investigated whether KIR/HLA genotypes and KIR haplotypes of donors and recipients exhibit a critical function in the prevalence of acute graft-versus-host disease (aGVHD) and persistence of the graft after HLA-identical sibling allo-HSCT for patients with hematological malignancies. Materials and methods: We studied KIR and HLA genotypes in 115 related donors and recipients (56 patients with AML and 59 patients with ALL) who had received allo-HSCT from HLA-matched sibling donors. We evaluated 17 KIR genes and some alleles, including their ligands, using the PCR-SSP assay. Results: KIR gene frequency results between donors and recipients showed that donors had more activating KIR than their recipients. Chi-square comparison of KIR genotype frequencies in donors versus recipients revealed a significant difference (P < 0.001). We found a survival association between the donor lacking and the recipient having group B KIR haplotypes, although this was not statistically significant. Conclusion: This study suggests that we could exploit NK cell alloreactivity as a part of the optimization of donor selection and potential immunotherapeutic regimens to help facilitate good engraftment and reduce the risk of aGVHD incidence after allo-HSCT.

Detection of BCR-ABL kinase domain mutations in patients with chronic myeloid leukemia on imatinib.

BCR-ABL tyrosine kinase domain mutations are the most important factor contributing to imatinib-resistance in patients with chronic myeloid leukemia. We used a semi-nested reverse transcriptase-polymerase chain reaction followed by bidirectional sequencing to detect mutations in a cohort of 110 chronic myeloid leukemia patients. In total, 34 mutations in 19 distinct codons were identified in 32 patients, of which D276N and E279A were novel. The most commonly mutated region was drug-binding site (29%) followed by P-loop region (26%) and most patients bearing them were in accelerated phase and blastic phase. This report expands the spectrum of BCR-ABL mutations and stresses the use of mutation testing in imatinib-resistant patients for continuation of treatment procedure.

Evaluation of T315I mutation frequency in chronic myeloid leukemia patients after imatinib resistance.

The occurrence of resistance mutations in the Abl kinase domain plays a central role in drug treatment failure in chronic myeloid leukemia (CML) patients. Among them, the T315I mutation at the gatekeeper position affects a common Abl kinase contact residue and confers complete resistance to all known ATP-competitive BCR-ABL inhibitors. In the present study, an allele-specific oligonucleotide reverse transcriptase polymerase chain reaction assay was used to detect T315I mutation in a cohort of 60 imatinib-resistant CML patients. In terms of disease phase, 43 patients (71%) were in late chronic phase, 4 (7%) in accelerated phase, and 13 (22%) in blastic phase. The prevalence of the T315I mutation was found to be 7% (4/60). All four patients with mutation were in advance phases and had previously lost all their responses. The results of the study confirmed that this method is low cost and easy tool to operate for T315I mutation screening and direct sequencing should be performed in positive cases for confirmation.