Galicia is a region situated in Northwest Spain with a population of Celtic origin. The geographical isolation and migratory patterns (high emigration rates throughout centuries and almost no ...immigration until recent years) has preserved its language and cultural identity. HLA class I and II alleles have been studied in 140 old ancestry unrelated Caucasian donors representative of the four different Galician provinces. Allele and phenotype frequencies were estimated by `maximum-likelihood' and phylogenetic trees were constructed from the allelic frequencies by the neighbor-joining method to obtain the genetic distances between populations. The most frequent haplotypes were A1-B8-DRB1*0301-DQB1*0201 (0.035), A2-B44-DRB1*0701-DQB1*0202 (0.025), A2-B49-DRB1*1302-DQB1*0604 (0.021), A29-B44-DRB1*0701-DQB1*0202 (0.018), and A2-B18-DRB1*1104-DQB1*0301 (0.018). Our results shown that Galicians are more related to other Spanish (Madrid, Murcia, Catalonia) and European populations with geographical proximity (France, Portugal), than those with Celtic origin (Ireland, Wales, Cornwall).
Although liver transplants show a special tolerogenic behaviour, rejection remains an important problem that involves several immunological mechanisms, some of which are unknown. Our study sought to ...analyze the influence of HLA-C polymorphism on short-term liver graft acceptance by HLA-C genotyping of 100 orthotopic liver transplant recipient-donor pairs. Recipients were statified according to the occurrence of acute rejection. HLA-Cw*06 allele appeared to be underrepresented among recipients without versus those with acute rejection or those in control groups. With regard to HLA-C allelic compatibility, the frequency of acute rejection or those in episodes decreased with fewer HLA-C mismatches. These findings suggest the participation of HLA-C molecules in liver graft alloresponses, involving HLA-C genotyping, as well as compatibility.
In liver transplantion, rejection is still an important problem, and the role of human leukocyte antigens (HLA) has not been clearly established. At present, the possible involvement of HLA-C antigen ...in liver transplantation is still unexplored. The aim of this work was to analyze the influence of HLA-C polymorphism on the outcome of liver transplantation. For this purpose, genotyping of 100 orthotopic liver transplant recipient-donor pairs for HLA-C was performed with polymerase chain reaction–sequence-specific primers (PCR-SSPs). Liver recipients were stratified according to the occurrence of acute rejection. Patients without acute rejection were found to have a lower frequency of the HLA-Cw*06 allele compared with those with acute rejection or the control group. Moreover, when the role of HLA-C dimorphism was analyzed, natural killer (NK)1-alloantigens were found to be predominant in recipients without acute rejection. When the match of HLA-C single alleles and NK-alloantigens between donor and recipient was analyzed, it appeared that the frequency of acute rejection gradually decreased with decrease of the number of allele mismatches. Graft survival was increased when the number of mismatches in both HLA-C or NK-alloantigens was lower. In conclusion, the HLA-C locus may play a role in liver graft alloreactivity or allotolerance and, therefore, may be useful to avoid acute rejection and to achieve graft acceptance, resulting in a better final outcome in liver transplantation. (Liver Transpl 2003;9:218-227.)
The incidence of alloimmune neonatal neutropenia combined with neonatal alloimmune thrombocytopenia is very low. We report a case of a neonate who suffered severe neutropenia and thombocytopenia with ...widespread petechial spots. The presence of alloantibodies in mother's and patient's sera was analyzed by lymphocytotoxicity test, agglutination test, granulocyte indirect immunofluorescence test, platelet immunofluorescence test (PIFT) and solid phase enzyme‐linked immunosorbent assay. Human neutrophil antigens (HNA) and human platelet antigen (HPA) genotypes were tested by polymerase chain reaction analyses. The mother's and patient's sera reacted with neutrophils and lymphocytes of the father. PIFT revealed the presence of IgG anti‐platelet antibodies in the patient's serum but the test was negative in the maternal serum. Analyses of HNA‐1 and HPA genotypes of the family revealed maternal‐neonatal HNA‐1a and HPA‐3b mismatch. The study of the mother's and patient's sera showed the presence of anti HNA1a, HPA‐3b and HLA antibodies specific for HLA‐A3 and HLA‐B38 antigens. These results suggest that the transplacental passage of maternal HNA‐1a, HPA‐3b and HLA alloantibodies caused neutropenia and thrombocytopenia in this patient.
Several authors have shown that anti-donor antibodies before liver transplantation are associated with decreased graft survival. The aim of this study was to investigate the relationship between ...anti-donor antibodies detected by the CDC technique or by FlowPRA, and acute or chronic rejection as well as graft survival. Furthermore, we sought to determine whether anti-donor antibodies, detected by the CDC technique, correlated with those discovered by cytometric screening. The acute rejection incidence among patients with complement-dependent cytotoxicity positive CDC cross-match was similar to that for patients with a negative cross-match. None of the patients with a positive cross-match developed chronic rejection. Allograft survival was significantly lower among recipients with a positive T-lymphocyte cross-match. Indeed, the majority of recipients with positive CDC cross-matches displayed graft failures before first postransplant year. The results of a positive FlowPRA determination were concordant with a positive CDC cross-match in 85.71% of cases. Our data demonstrate that pretransplant FlowPRA correlates with the final CDC cross-match results. This finding suggests that in the future prospective pretransplant antibody screening with FlowPRA or CDC techniques may be useful to identify high-risk recipients.
In this study we have evaluated the role of HLA matching and pretransplant crossmatch in the 2 year graft survival of 112 consecutive patients who underwent lung transplantation in our hospital. HLA ...class I typing was performed following a standard CDC assay and class II was analyzed by PCR-SSO and PCR-SSP methos. The pretransplant crossmatch test was performed by standard CDC technique. Survival functions estimates were computed using Kaplan-Meier method and the generalized Wilcoxon test. Positive pretransplant crossmatch was found in 4 patients, that shown a statistical significance reduced survival curve than those with negative crossmatch (50% vs. 77%, p=0.03). There were no significant differences on lung graft survival curves when the antigen mismatches for HLA-A, -B and -DR loci were analyzed (p>0.05). Since there is a clear influence of crossmatch results in the lung transplant survival, studies with a large serie will be necessary to evaluated the effect of HLA matching.
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