B7家族新成员HHLA2的研究进展

Research progress of new mumber HHLA2 of B7 family

HHLA2是新发现的B7家族成员。HHLA2在正常组织中的表达是有限的。TMIGD2,是已经确定的HHLA2的受体之一。与HHLA2一样,TMIGD2不存在于老鼠中而存在于人和灵长类动物中。HHLA2具有抑制CD4和CD8 T细胞增殖,同时还具有抑制T细胞分泌某些细胞因子的作用。HHLA2在正常组织中的表达是有限的,只表达于一些组织的上皮细胞中,但在包括肺癌、乳腺癌及骨肉瘤等多种恶性肿瘤中高表达。这也使HHLA2可能成为人类肿瘤相关治疗靶点。

HHLA2 is a newly discovered B7 family member. HHLA2 appears to have limited expression in normal tissues. TMIGD,one of the receptors HHLA2 is established. Similar to HHLA2,TMIGD2 is absent in mouse and rat while it is found in human and higher primates. HHLA2 with inhibition of CD4 and CD8 T cell proliferation,but also can inhibit the role of T cells secrete some cytokines. HHLA2 protein is absent in most normal tissues,but mainly expressed on epithelial cells of a few tissues. But HHLA2 is widely expressed in various human cancers such as lung cancer,breast cancer and osteosarcoma et al,that make HHLA2 might be a new target for human cancers immunotherapy.