RESUMO
The HLA compatibility continues to be the main limitation when finding compatible donors, especially if an identical match is not found within the patient's family group. The creation of bone marrow registries allowed a therapeutic option by identifying 10/10 compatible unrelated donors (URD). However, the availability and frequency of haplotypes and HLA alleles are different among ethnic groups and geographical areas, increasing the difficulty of finding identical matches in international registries. In this study, the HLA-A, -B, -C, -DRB1, and -DQB1 loci of 1763 donors registered in the Colombian Bone Marrow Registry were typed by next-generation sequencing. A total of 52 HLA-A, 111 HLA-B, 41 HLA-C, 47 HLA-DRB1, and 20 HLA-DQB1 alleles were identified. The 3 most frequent alleles for each loci were A*24:02g (20,8%), A*02:01g (16,1%), A*01:01g (7.06%); B*35:43g (7.69%), B*40:02g (7.18%), B*44:03g (6.07%); C*04:01g (15.40%), C*01:02g (10.49%), C*07:02g (10.44%); DRB1*04:07g (11.03%), DRB1*07:01g (9.78%), DRB1*08:02g (6.72%); DQB1*03:02g (20.96%), DQB1*03:01g (17.78%) and DQB1*02:01g (16.05%). A total of 497 HLA-A-C-B-DRB1-DQB1 haplotypes were observed with a frequency greater than or equal to 0.05% (> 0.05%); the haplotypes with the highest frequency were A*24:02g~B*35:43g~C*01:02g~DQB1*03:02g~DRB1*04:07g (3.34%), A*29:02g~B*44:03g~C*16:01g~DQB1*02:01g~DRB1*07:01g (2.04%), and A*01:01g~B*08:01g~C*07:01g~DQB1*02:01g~DRB1*03:01g (1.83%). This data will allow the new Colombian Bone Marrow Donor Registry to assess the genetic heterogeneity of the Colombian population and serve as a tool of interest for future searches of unrelated donors in the country.
Assuntos
Medula Óssea , Antígenos HLA-C , Humanos , Antígenos HLA-C/genética , Haplótipos , Cadeias HLA-DRB1/genética , Frequência do Gene , Alelos , Colômbia , Antígenos HLA-B/genética , Doadores não Relacionados , Antígenos HLA-A/genética , Sequenciamento de Nucleotídeos em Larga Escala , Sistema de Registros , Células-TroncoRESUMO
Hematopoietic progenitor cell (HPC) transplantation is a treatment option for malignant and nonmalignant diseases. Umbilical cord blood (UCB) is an important HPC source, mainly for pediatric patients. It has been demonstrated that human leukocyte antigen (HLA) matching and cell dose are the most important features impacting clinical outcomes. However, UCB matching is performed using low resolution HLA typing and it has been demonstrated that the unnoticed mismatches negatively impact the transplant. Since we found differences in CD34+ viability after thawing of UCB units matched for two different patients (p = 0.05), we presumed a possible association between CD34+ cell viability and HLA. We performed a multivariate linear model (n = 67), comprising pre-cryopreservation variables and high resolution HLA genotypes separately. We found that pre-cryopreservation red blood cells (RBC), granulocytes, and viable CD34+ cell count significantly impacted CD34+ viability after thawing, along with HLA-B or -C (R2 = 0.95, p = 0.01; R2 = 0.56, p = 0.007, respectively). Although HLA-B*40:02 may have a negative impact on CD34+ cell viability, RBC depletion significantly improves it.
Assuntos
Comunicação Celular , Eritrócitos/metabolismo , Sangue Fetal/citologia , Antígenos HLA/genética , Células-Tronco Hematopoéticas/metabolismo , Alelos , Antígenos CD34/metabolismo , Comunicação Celular/genética , Sobrevivência Celular/genética , Transplante de Células-Tronco de Sangue do Cordão Umbilical , Criopreservação , Células-Tronco Hematopoéticas/citologia , HumanosRESUMO
Allele and haplotype frequencies were calculated from 1463 umbilical cord blood (UCB) units, from Bogotá (Colombia) donors, HLA-typed in high resolution. This is the first report using allele-level typed colombian samples of five HLA loci related to hematopoietic stem cell transplantation (HLA-A, -B, -C, -DRB1 and -DQB1). The most frequent haplotype found in our sample was A*24:02gâ¯â¼â¯B*35:43gâ¯â¼â¯C*01:02gâ¯â¼â¯DRB1*04:07gâ¯â¼â¯DQB1*03:02g (4.14%). Our data are available at the Allele Frequencies Net Database under the code AFND3604.