Since it has been recently shown that recombinant TRAIL administration might participate to the resolution phase of asthma, by promoting apoptosis of infiltrating leukocytes [9], we next evaluated whether the decreased number of BAL infiltrating cells in OVA-challenged animals i.n. pretreated with TRAIL might be due to induction of apoptosis. The gene discussed is TNFSF10; the disease is asthma.