HLA antigen compatibility between patients with hematologic diseases and their parents / 中国实验血液学杂志

This study was aimed to investigate and analyze the HLA antigen compatibility between patients with hematologic diseases and their parents so as to provide basis for selecting the suitable donors in haploidentical hematopoietic stem cell transplantation. The HLA low resolution for 174 families was typed and analyzed by using PCR-SSP. The results showed that 52.30% of patients with hematologic diseases possessed father and/or mother with HLA matching over haploidentity, 10.92% patients were over 8/10 matched with their father and/or mother. 11.49% were over semi-matched with both their father and mother. The rate of 6/10 matched pairs (28.16%), 7/10 matched pairs (16.1%) and 8/10 matched pairs (8.62%) were all beyond 5%; 9/10 (2.3%) and 10/10 matched pairs (1.15%) were all below 5%. It is concluded that with the matching degree increasing between two generations, HLA matching rate is decreasing. Over 50% and 10% patients were over HLA semi-matched and 8/10 matched with their father and/or mother, respectively. This high matching rate offered a big chance for success of haploidentical HSCT. Patients are more likely over semi-matched with their father and/or mother when they have high frequency and strong linkage HLA disequilibrium. High frequency and strong linkage disequilibrium in populations are main reason, and population concentrating and isolated living may be another reason for this phenomenon.

Clinical analysis for 3 cases of HLA-matched between father and son and 1 case of post-hematopoietic stem cell transplant efficacy / 中国实验血液学杂志

Getting a HLA-matched donor is a key factor for successful hematopoietic stem cell transplantation. People are almost semi-matched with their parents, while a person HLA-matched with his/her father or mother was rarely seen, if so, usually whose father and mother are genetically related. HLA-low resolution for patients and their relatives were performed using PCR-SSP technique and three patients were found HLA-matched with their father in these results. One of them accepted hematopoietic stem cell transplantation using his HLA-matched father as his donor. The results showed that the chimerism was detected as stable complete donor chimerism, fusing gene of MLL-ENL was detected all negatively in the post-transplant period. This case got well hematopoietic reconstruction and GVHD didn't occur, so far he has survived for two years in health conditioning. It is concluded that people HLA-matched with his/her father or mother can be found when there is one identical haplotype of high frequency and strong linkage disequilibrium between father and mother. This case is valuable for hematopoietic stem cell transplantation development.

A recombination event occurring between HLA-A and -A loci from father's HLA haplotype chromosome / 中国实验血液学杂志

This study was aimed investigate the recombination event occurring between HLA-A and-A loci discovered from father's HLA haplotype chromosome in a family. Peripheral blood samples were collected from a family. HLA class I (-A, -B, and -Cw) and II (-DRB1 and -DQB1) alleles were amplified and typed by both low and high resolution PCR with sequence-specific primers (PCR-SSP) and sequence-based typing (SBT). The results showed that 2 haplotypes of the patient were A(*)3001-B(*)1302-DRB1(*)0701 and A(*)3001-B(*)5601-DRB1(*)1454 respectively, those of her father were A(*)3001-B(*)1302-DRB1*0701 and A(*)1101-B(*)5601-DRB1(*)1454. Family analysis demonstrated that the patient's A(*)3001-B(*)1302-DRB1(*)0701 came from her mother and A(*)1101-B(*)5601-DRB1(*)1454 came from her father, but the A of patient was A(*)3001 and B, DR were the same to her father. This showed that the chromosome exchange and recombination event of father's 2 haplotypes occurring between HLA-A and -A loci at meiosis. And recombinate haploid chromosome was completely inherited to his daughter 1. HLA typing and Paternity testing demonstrated that father was the natural father, and the recombination event occurring between HLA-A and -A loci of the daughter 1 with father's HLA haplotype chromosome. It is concluded that the HLA-A/A of father's HLA haplotype chromosome recombination event occurring between HLA-A an-A loci has been found in a family in China, which helps further study on the mechanisms of HLA recombination.

Dynamic detection of chimerism and fusion gene in chronic myeloid leukemia patients relapsed after allogeneic hematopoietic stem cell transplantation / 中国实验血液学杂志

This study was aimed to investigate the chimerism and fusion gene expression in patients with CML after allo-HSCT, to analyse engraftment and minimal residual disease by using STR-PCR combined with RT-PCR qualitative and quantitative assays, and to evaluate their clinical value for predicting disease relapse. 4 relapsed patients with CML after allo-HSCT were dynamically investigated. Qualitative analysis of donor chimerism was performed by multiplex PCR amplification of STR markers and capillary electrophoresis with fluorescence detection, qualitative detection of bcr/abl transcripts was performed by RT-PCR. The results showed that the 100% donor chimerism appeared in 4 patients on day 28 after transplantation and bcr/abl expression was negative, but the 4 patients were in status of unstable mixed chimerism (DC: 0% - 80.4%) at the different time points during the following up with bcr/abl gene positive. 2 patients of them were continuously mixed chimerism after relapse of CML, the other 2 changed from MC to CC by intervention of clinical treatment. Decreasing values of donor chimerism were detected prior to the occurrence of graft rejection and CML relapse, and bcr/abl gene expression was positive. It is concluded that the results of STR-PCR in the range of its sensitivity fully correspond with bcr/abl tests in patients. The combination of STR-PCR with RT-PCR will provide a highly sensitive and valuable tool for evaluating engraftment, graft rejection, and relapse and predicting GVHD. Furthermore, it can provide a basis for early intervention of clinical treatment, and can identify these high risk patients with molecular or cytogenetic relapse after allo-HSCT.