CHARACTERIZATION OF THE ANTIGEN-PRESENTING CELL AND T-CELL REQUIREMENTS FOR INDUCTION OF PULMONARY EOSINOPHILIA IN A MURINE MODEL OF ASTHMA

A model of allergic pulmonary inflammation is described in which the i ntraperitoneal injection of antigen (Ag)-pulsed cells resulted in T ce ll priming. Mice received two injections of 10(6) elicited peritoneal macrophages, which had been incubated with Ag for 48 hr, on Days 0 and 6, followed by an aerosol Ag challenge on Day 19. BronchoalveoIar lav age fluid harvested on Day 21 contained increased eosinophil numbers a nd resembled the cell influx observed following immunization with Ag i n alum. Incubation of Ag-presenting cells with interferon-gamma result ed in increased expression of the costimulator molecule B7-2 and of MH C Ags, but did not enhance priming capacity. Using this system, antibo dies to CD4 and CD8 were tested for their ability to block sensitizati on by Ag-pulsed cells. Both anti-CD4 and anti-CD8 antibodies completel y blocked the airway eosinophil response following aerosol Ag challeng e. This model will be very useful for characterization of the interact ions between Ag-presenting cells and T cells which ultimately result i n the induction of pulmonary eosinophilia. (C) 1996 Academic Press, In c.