人血小板膜糖蛋白CD36缺陷与免疫性血小板减少症等疾病密切相关，但CD36在血小板表面组织特异性表达和缺陷的分子机制尚不明确。本项目拟在课题组前期研究的基础上，开展血小板CD36 II型缺陷分子机制研究。通过脐血造血干细胞体外定向培养获得血小板前体巨核细胞，以cDNA末端快速扩增技术，阐明巨核系特异性CD36基因mRNA转录本结构。分析比较CD36 II型缺陷和阳性表型个体，在启动子序列变异、CpG岛甲基化、mRNA转录本序列变异等方面的差异。并选用启动子荧光素酶报告系统、CD36基因去甲基化重表达、变异型mRNA转录本体外表达等手段，研究CD36基因的巨核系特异性转录调控、mRNA序列变异等与血小板CD36 II型缺陷的相关性，阐明血小板CD36 II型缺陷的分子机制。项目的实施对于理解免疫性血小板减少症的发病机理、血小板输注无效等患者的安全输血等具有重要意义。

The CD36 deficiency on human platelets may play an important role in the pathogenesis of some disease such as alloimmune thrombocytopenia, but the molecular basis of tissue-specifical expression or deficiency of CD36 on platelets is still unclear. This project will research for the molecular basis of type II CD36 deficiency on platelets, which was based on our previously studies. The megakaryocytes, precursor of platelets, were cultured from henatopoietic stem cells of cord blood in vitro. The mRNA transcript structure of CD36 gene in megakaryocytes was identified by the technique of rapid amplification of cDNA ends. The differences on promoter sequences, methylation on CpG islands and mRNA sequences were analyzed and compared between type II CD36 deficiency and positive phenotypes. The relationship of the differences and CD36 deficiency was explored using the techniques of promoter-luciferase reporter system, demethylation and re-expression of CD36 gene, mRNA variant expression in vitro. The research will clarify the molecular basis of type II CD36 deficiency on platelets. In totally, the performance of the project is signality on understanding the pathogenesis of alloimmune thrombocytopenia, and will help to supply the safe blood to the patients with platelet transfusion refractoriness.