Genetic Analysis of HLA- and HPA-Typing in Idiopathic (Autoimmune) Thrombocytopenic Purpura Patients Treated with Cepharanthin

Abstract

We performed genetic analysis of human leukocyte antigen (HLA) and human platelet antigen (HPA) in 45 patients with cepharanthin-treated idiopathic thrombocytopenic purpura. HLA-typing was performed by the polymerase chain reaction-restriction fragment length polymorphism method, and HPA-typing by a polymerase chain reaction-sequence-specific primer method. There were 14 responders and 31 nonresponders. Responders included many patients who had already been treated with prednisolone. HLA-DRB1 0901 was significantly more common in responders than in nonresponders. In contrast, HLA-DRB1*0410 and DQB1*0401 were significantly more common in nonresponders. The a/b genotype of HPA-2a/2a (Ko^b/Ko^b) was significantly increased in responders. In contrast, HPA-2a/2b (Ko^b/Ko^a) and HPA-3a/3b (Bak^a/Bak^b) were significantly more common in nonresponders. These findings suggest that genetic studies of HLA and HPA can predict the response of idiopathic thrombocytopenic purpura to cepharanthin.

Key Words:

• Idiopathic thrombocytopenic purpura
• Cepharanthin
• Polymerase chain reaction-restriction fragment length polymorphism
• Human leukocyte antigen
• Human platelet antigen