Research progress of new mumber HHLA2 of B7 family / 中国免疫学杂志

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.