γδT cells represent one unique recognition pattern,the limited recognition,which distinguishes from the specificrecognition for αβT cells and pattern recognition for macrophages.Vδ1 γδT cell is the major subset of human γδT cells,which predominates in mucosal tissue including the intestinal epithelia.Presently,a few antigens thathuman Vδ1TCR can recognize have been identified.Among them,MHC class I chain-related molecules A (MICA)have been studied most intensively.Besides Vδ1TCR,MICA is also the ligand of NKG2D,a C-type lectin-likeactivating immunoreceptor.In human,only Vδ1 cells can simultaneously express both types of receptors of MICAwhile NK cells,αβT cells and other subsets of γδT cells likewise express NKG2D.Although the precisemechanisms are still enigmatic,this distinct pattern of Vδ1 cells recognizing MICA predicts unique biologicalsignificance of Vδ1 cells in immune defense.Recent years,some progresses have been made in this issue.In thisreview we summarize the related reports and put forward some novel views based on our group’s studies.Cellular& Molecular Immunology.2005;2(4):253-258. γδ T cells represent one unique recognition pattern, the limited recognition, which distinguishes from the specific recognition for αβ T cells and pattern recognition for macrophages. Vδ1 γδ T cell is the major subset of human γδ T cells, which predominates in mucosal tissue including the intestinal epithelia. Presently, a few antigens thathuman Vδ1TCR can recognize have been identified .Among them, MHC class I chain-related molecules A (MICA) have been studied most intensively.Besides Vδ1TCR, MICA is also the ligand of NKG2D, a C-type lectin-like activating immunoreceptor . In human, only Vδ1 cells can simultaneously express both types of receptors of MICAwhile NK cells, αβT cells and other subsets of γδT cells likewise express NKG2D. Although the precise mechanisms of still enigmatic, this distinct pattern of Vδ1 cells recognizing MICA predicts unique biologicalsignifications of Vδ1 cells in immune defense. Last years, some progresses have been made in this issue. Thisreview we summarize the related reports and put forward some novel views based on our group’s studies. Cellular & Molecular Immunology. 2005; 2 (4): 253-258.