Background: Human platelet antigen (HPA) genotyping is important for epidemiological studies because the prevalence of particular HPA allotypes differs among various populations and plays a major role in the occurrence of HPA alloimmunization. In Caucasians, antibodies to HPA-1a are the most important causes of neonatal alloimmune thrombocytopenia (NATP). Recent studies suggest that anti-HPA 15a/15b (Gov b, Gov a) might be the most likely candidate antibodies following anti-HPA-1a in inducing NATP.
Methods: In the present study, HPA-15 system genotype was determined by PCR-SSP method in 279 unrelated subjects from the Croatian population, yielding an HPA-15a and HPA-15b frequency of 0.53 and 0.47, respectively.
Results: Retrograde testing for the presence of anti-HPA-15 antibodies by use of MAIPA in 39 frozen serum samples from serologically negative cases of clinically suspect NATP produced negative results.
Conclusion: The clinical role of anti-HPA-15 alloantibodies was unable to be confirmed.