As Lamina propria mononuclear cells (LPMCs), mucosal immune cells from the GALT, are highly susceptible for HIV infection and can be infected efficiently by CCR5-tropic HIV-1 strains, the Lamina propria aggregate culture (LPAC) can be used as an efficient ex vivo model to study HIV infection close to the physiological background [8]. The gene discussed is CCR5; the disease is HIV infectious disease.