For example, it was reported that ICOS−/− mice were more susceptible to bacterial (such as M.tuberculosis [25], C.muridarum [26], and S.enterica [27], etc.)and parasitic (such as S.mansoni [28], T.gondii [29], and T.spiralis [30], etc.)infections, and the Th1 response was weakened and the pathological changes caused by pathogens were aggravated. The gene discussed is ICOS; the disease is infection.