[Effects of piperacillin on the immunologic functions of macrophages].

In this study, the possible effects of piperacillin on three immune functions of human blood monocytes-macrophages were investigated. Monocytes and macrophages were isolated from the circulating blood of normal subjects by density gradient centrifugation followed by adhesion to plastic material. The cells were incubated for 30 to 60 min with different concentrations of piperacillin, then tested on the following models: presentation by the monocytes-macrophages of an exogenous antigen to autologous lymphoid cells, with evaluation of the proliferative response to tuberculin; secretion of interleukin-1 by monocytes-macrophages stimulated or not by lipopolysaccharide, with measurement of the culture supernatants ability to stimulate rat thymocytes; release to prostaglandin E2 by monocytes-macrophages with evaluation of its indomethacin-inhibitable suppressive effect on lymphoproliferative responses to a polyclonal mitogen. In none of these tests did piperacillin show and immunodepressant or immunostimulant effect.