Response of human intestinal lamina propria T lymphocytes to interleukin 12: additive effects of interleukin 15 and 7. Gut 43:620–628

Background/Aim—Interleukin (IL) 12 is involved in the mucosal response during intestinal inflammation but its role is not fully understood. The response of human lamina propria T lymphocytes (T-LPL) to IL-12 in terms of interferon ã (IFN-ã) release and proliferation was investigated, exploring whether IL-15 and IL-7 cooper-ate with IL-12. The role of accessory mol-ecules (CD2 and CD28) was also investigated. Methods—Unstimulated and phytohae-magglutinin preactivated T-LPL cultures were incubated with or without the initial addition of cytokines, anti-CD2 or anti-CD28 antibodies. IFN-ã mRNA was de-tected by reverse transcriptase polymerase chain reaction, and protein secretion was measured by enzyme linked immunosorbent assay (ELISA). Results—IFN-ã mRNA was induced i