Suggestive evidence of a role of HLA-DRB4 mismatches in the outcome of allogeneic hematopoietic stem cell transplantation with HLA-10/10-matched unrelated donors: a French-Swiss retrospective study.

We have conducted a retrospective study on 251 patients from three centers in France and Switzerland between 2004 and 2010 with the goal to evaluate the impact of HLA-DRB3/B4/B5 allele mismatching after HLA-10/10-matched unrelated allogeneic hematopoietic stem cell transplantation (HSCT). Fourteen (5.5%) patients receiving HSCT from an HLA-10/10-matched unrelated donor had a mismatched DRB4 donor, 23 (9.5%) patients had a mismatched DRB3 donor and 214 (85%) had a fully matched unrelated donor (HLA-10/10) without DRB3- or DRB4-mismatched donor. We compared the outcomes of 37 patients with a DRB3 or DRB4 mismatch with the rest of the population. The median survival for a patient without DRB3/4 mismatch was 18 months (95% confidence interval (CI), 13-29), for DRB3-mismatched patients 32 months (95% CI, 13-NR) and for DRB4-mismatched patients 7 months (95% CI, 3-NR). The multivariate analysis showed a significant impact of DRB4 mismatching on survival (Hazards ratio (HR)=2.1 (95% CI, 1.01-4.67), P=0.045), acute GvHD (HR=2.66 (95% CI, 0.99-7.09) P=0.05) and on transplant-related mortality (HR=2.8; (95% CI, 1.7-4.4) P=0.024). In the view of an impact of DRB4 locus mismatch on clinical outcome, it would be important to confirm this observation in a prospective study as it may be worth considering DRB4 in the unrelated donor selection.

Is there any impact of HLA-DPB1 disparity in 10/10 HLA-matched unrelated hematopoietic SCT? Results of a French multicentric retrospective study.

We retrospectively analyzed the impact of HLA-DPB1 mismatches in a large cohort of 1342 French patients who underwent 10/10 HLA-matched unrelated HSCT. A significant impact of HLA-DPB1 allelic mismatches (2 vs 0) was observed in severe acute GVHD (aGVHDIII-IV) (risk ratio (RR)=1.73, confidence interval (CI) 95% 1.09-2.73, P=0.019) without impact on OS, TRM, relapse and chronic GVHD (cGVHD). According to the T-cell epitope 3 (TCE3)/TCE4 HLA-DPB1 disparity algorithm, 37.6% and 58.4% pairs had nonpermissive HLA-DPB1, respectively. TCE3 and TCE4 disparities had no statistical impact on OS, TRM, relapse, aGVHD and cGVHD. When TCE3/TCE4 disparities were analyzed in the graft-vs-host or host-vs-graft (HVG) direction, only a significant impact of TCE4 nonpermissive disparities in the HVG direction was observed on relapse (RR=1.34, CI 95% 1.00-1.80, P=0.048). In conclusion, this French retrospective study shows an adverse prognosis of HLA-DPB1 mismatches (2 vs 0) on severe aGVHD and of nonpermissive TCE4 HVG disparities on relapse after HLA-matched 10/10 unrelated HSCT.

Characterization of the B*5002-Cw*0602-DRB1*0406-DQB1*0402 Haplotype: impact on the unrelated-bone marrow donor search strategy.

Improvements in HLA-typing by DNA-based methods now allow accurate genotyping of unrelated bone marrow (UBM) donors and recipients and also definition of haplotypes. In this regard, B*5002 has been predicted in linkage disequilibrium with Cw*0602, DRB1*0406 and DQB1*0402 based on the frequency of allele coexistence. Here, we confirm this assumption by HLA genotyping of four informative families and three unrelated individuals. In the four families, the extended haplotype HLA-B*5002, -Cw*0602, -DRB1*0406, DQB1*0402 can be definitely assigned by the mode of heritance. Furthermore, this association of alleles was also found in the three B*5002 unrelated individuals. Knowledge of the frequent linkage disequilibrium of these rare alleles can improve UBM donor search strategies.

HLA-DRB and -DBQ typing by PCR amplification using sequence-specific primers (PCR-SSP): assessment after 1 year of routine use by three laboratories.

Using sequence-specific amplifications, a practical and fast technique for DRB and DQB typing has been developed. The primers are chosen in order to amplify groups of alleles corresponding to the same serological specificity. In a second step, precise allelic determination is obtained by studying the restriction fragment length polymorphism of the PCR products. The experience of three laboratories using this technique in the context of organ or bone marrow transplantation is reported.

Improvement in HLA-DQB typing by PCR-RFLP: introduction of a constant restriction site in one of the primers for digestion control.

The PCR-RFLP method previously reported by Inoko is a powerful technique for HLA class II typing. The reliability of RFLP interpretation depends on complete digestion by restriction endonucleases using a modified primer with restriction sites as an internal digestion control. The use of restriction enzymes which recognize specific HLA DQB allelic variations makes HLA DQB genotyping possible.

Familial Crohn's disease in multiple siblings: no linkage to the HLA system.

We report five families with 3 or more children having Crohn's disease. In one family, 6 out of 11 siblings were affected. HLA haplotype study in affected children showed that the probability of random segregation was only 38 percent, making improbable a linkage between the histocompatibility locus and the development of Crohn's disease. However similar clinical patterns in siblings could suggest a genetic factor not linked to the HLA system.

Screening heterozygotes for 21-hydroxylase deficiency among hirsute women: lack of utility of the adrenocorticotropin hormone test.

Heterozygosity for 21-hydroxylase deficiency (21-OHD) was investigated in 174 adult hirsute women by using the sum of the incremental responses of serum 17 alpha-hydroxyprogesterone (17 alpha-OHP) and progesterone (P) (delta 17 alpha-OHP + P), 60 minutes after a 0.25 mg intravenous (IV) bolus of synthetic adrenocorticotropic hormone (ACTH). The distribution of 17 alpha-OHP + P in hirsute women was bimodal, allowing two subgroups to be distinguished. In one subgroup including 137 patients, the mode was similar to controls and all values were lower than 3 ng/ml. Thirty-seven (21%) patients constituted another subgroup with values higher than 3 ng/ml and could a priori have been considered as heterozygotes for 21-OHD. However, human leukocyte antigen genotyping provided no conclusive evidence that this subgroup included exclusively heterozygotes for the 21-OHD.

Type IIa hyperlipoproteinemia and HLA-A and B antigens: no association.

One hundred unrelated patients with type IIa hyperlipoproteinemia have been investigated for their HLA-A and B antigens and compared to 171 normal controls. This study does not support the significant increase of HLA-B17 and Bw35 previously reported by others.

[Immunization with antigen D. Results obtained with 118 volunteers]. / L'immunisation à l'antigène D. Résultats obtenus chez 118 volontaires.

During the last four years, 118 blood donors have been immunized to obtain plasma with a high level anti-D in order to prepare anti-D immunoglobulins. The results of the immunizing schedule are very successful, as we have obtained anti-D of titer superior to 256 in 96,36% of the cases (Coombs technic). However, the development of unwanted antibodies outside the Rh system (anti-Jka: 6, anti-Fya: 5) has led us since November 1979 to use phenotyped blood without undesirable red blood cell antigens. No irregular antibody has developed since except for an anti-Yta. The anti-HLA have been observed with a frequency of 36%. The use of frozen/thawed and phenotyped blood without undesirable red blood cell antigens can allow to obtain a high level of anti-D without risk for the donors. Nevertheless, the exceptional immunization to a public antigen persists.