The RhCcEe phenotype incompatibility in Chinese and presence of DEL in serologically D–, C/E+ individuals

Abstract

Background

Red cell antibodies of a certain specificity are produced following the immunization of a corresponding antigen-negative individual through pregnancy or transfusion, such as RhCcEe allogeneic infusion. The transfusion incompatibility of RhC/c and RhE/e can be estimated based on the proportion of the RhCcEe phenotype. DEL has been positively correlated with RhC and RhE phenotypes. Elucidating the RhCcEe phenotype may facilitate the identification and screening of DEL variants.

Objective and methods

The risk of alloimmunization due to RhC/c and RhE/e incompatibility were estimated by analyzing the frequency of RhCcEe phenotypes in 783 RhD negative blood donors and more than 458,000 RhD positive individuals. DEL screening was performed on RhC+ and/or RhE+ samples from RhD negative population. A total of 106 RhC+ and(or) RhE+ RhD negative blood donors were selected for DEL screening using an absorption and elution test, fluorescent probe-based quantitative PCR, and RHD sequencing.

Results

Significant differences in RhCcEe phenotype distribution were observed between RhD positive and RhD negative Chinese individuals. Among RhD-positive Chinese individuals, the transfusion incompatibility rates for E/e and C/c were notably high at 31.09 % and 34.04 %, respectively. The highest alloimmunization risks were observed for anti-c (24.889 %), followed by anti-E (24.731 %). The RhD negative population had the highest alloimmunization risk of anti-C(24.257 %). Among the 106 RhC+ and(or) RhE+ D-negative samples, thirty-four DELs were observed, with a proportion of 16.27 %. Thirty-two DELs were confirmed to have the RHD 1227G>A allele. Two DEL cases have RHD-CE-D hybrid alleles, including one RHD-CE(3−9)-D and one RHD-CE(3−6)-D.

Conclusion

We have determined the prevalence of RhCcEe phenotypes in Chinese and derived the incompatibility of E/e and C/c in the same population, enabling the estimation of their potential alloimmunization risk. The RhC+ phenotype, in conjunction with the anti-D adsorption-elution test and the RHD 1227A allele PCR technique, can effectively differentiate true RhD-negative individuals from those with the DEL phenotype.