MODULATION OF INVIVO IMMUNE-RESPONSE BY SELECTIVE DEPLETION OF NEUTROPHILS USING A MONOCLONAL-ANTIBODY, RP-3 .1. INHIBITION BY RP-3 TREATMENT OF THE PRIMING AND EFFECTOR PHASES OF DELAYED-TYPE HYPERSENSITIVITYTO SHEEP RED-BLOOD-CELLS IN RATS

Recent studies on neutrophils have revealed that these cells produce v arious cytokines, and may be involved in regulation of the immune resp onse. We examined whether neutrophils are involved in delayed type hyp ersensitivity (DTH) to SRBC in rats by selective depletion of in vivo neutrophils using a mAb designated RP-3. When the rats had been treate d with RP-3 at the time of priming with SRBC, DTH to these cells was i nhibited. Furthermore, RP-3 treatment was effective in inhibiting the effector phase of the DTH response to SRBC. When spleen cells from rat s that had been treated with RP-3 at the time of immunization were use d for local transfer of DTH, footpad swelling was significantly less t han that induced by spleen cells from the RP-3-untreated immune rats.