Abstract: Objective To explore the security of DEL red blood cells transfusion to Rh negative recipient. Methods IAT and adsorption-elution were performed on the investigated blood samples to test RhD-negative recipients and DEL phenotype. RHD genotyping were performed with gene sequencing for DEL phenotypes,anti-D alloimmunization was investigated in RhD-negative recipients transfused with DEL red blood cells. Results All the DEL donors were confirmed to carry RHD RHD1227A allele. The titer and strength of anti-D antibodies of 12 true D-negative recipients who were transfused with DEL blood showed no significant difference. However,the titer of anti-D antibodies of one true D-negative recipient increased from 8 to 32.Conclusions Alloanti-D immune response induced by DEL is a rare event in true D-negative recipients. But DEL donors should be excluded for transfusion to D-negative recipients who had carried anti-D.

Key words: DEL, Anti-D, RHD1227A allel, Rh blood group