ADMINISTRATION OF ANTIGRANULOCYTE MONOCLONAL-ANTIBODY RB6-8C5 PREVENTS EXPRESSION OF ACQUIRED-RESISTANCE TO LISTERIA-MONOCYTOGENES INFECTION IN PREVIOUSLY IMMUNIZED MICE

Recent studies have established the importance of neutrophils in innat e resistance to Listeria monocytogenes infection in mice, The purpose of this study was to determine the importance of neutrophils in acquir ed resistance to L. monocytogenes infection. Previously immunized mice that were depleted of neutrophils by administration of the antigranul ocyte monoclonal antibody RB6-8C5 demonstrated less resistance to L. m onocytogenes challenge than did nonimmunized control mice. In contrast , immunized control mice exhibited a heightened resistance to rechalle nge, as expected. These results suggest that neutrophils make previous ly unrecognized contributions to acquired immunity to a facultative in tracellular pathogen.