Integrins are conformation-regulated adhesion molecules, which play essential roles in many biological processes, especially for immunity [1] . Structurally, integrins are a group of heterodimeric transmembrane receptors, which contain α subunit and β subunit. In mammals, there are 18 kinds of α subunit and 8 kinds of β subunit were discovered, which form 24 combinations (Table 1) [2,3 ]. Overall, these 24 kinds of integrins can be divided to two groups by containing α-I domain (Table 1 and

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... re 1A ) or not (Table 1 and Figure 1B ). Integrin can regulate its ligand-binding affinity by conformational changes [1]. The adaptor proteins and signal pathways were broadly studied, as discussed in ref 1 [1]. Integrins are one of the most important adhesion molecules mediating cell-cell interactions and cell-extracellular matrix interactions. In immunity, integrins play critical roles in leukocyte adhesion from blood flow [1,4-6] cell migration [7], immunological synapse [8,9] and phagocytosis [10]. Thousands of scientific studies (PubMed: 63538 total, 18067 in immunology catalog; Web of Science: 236304 total, 52308 in immunology catalog) were presented up to data. When plotting the number of integrin studies by time (Figure 2), we can see the number of integrin-relevant studies was raised at 1980s, and