Postinflammatory Increase of Pathogenicity of Lymphocytic lnocula in the Peritoneal Cavity

Abstract

Passive transfer of experimental allergic encephalomyelitis in rats by intraperitoneal injection of cells from draining lymph nodes was usually unsuccessful unless very large numbers of cells or conditioning procedures were employed. If the ip injection was done during the healing phase of a chemical peritonitis. then its effectiveness was greatly increased, even exceeding that of the iv route. The same effect of a healing chemical peritonitis was observed in adrenalectomized rats. A regional graft-versus-host disease produced by ip injection of parental spleen cells into hybrid recipients was greatly augmented in the healing phase of a chemical peritonitis. A host-versus-graft reaction against allogeneic spleen cells was histologically detectable only when the cells were injected after a chemical peritonitis. All these results are explicable as the consequence of a postinflammatory increase of absorption of lymphocytic inocula into the draining lymph nodes. The production of a chemical peritonitis is likely to be useful wherever immunologic and pathologic experimentation requires ip inoculations.