[Swine alveolar macrophages: description and functional analysis].

Swine alveolar macrophages (SAM) were characterized according to several properties: this spherical cell is able to adhere in vitro to plastic and glass substrata. Its size varies from 10 to 20 mu; on the cytochemistry level, up to 85% SAM appear to be peroxidase-negative, whereas they are all esterase-positive. The SAM phagocytic capacities were investigated by using three different substrata: zymosan, chicken red blood cells and Listeria monocytogenes. SAM were also characterized by their "accessory" function in mitogen-induced lymphocyte proliferation: under our experimental conditions SAM were not shown to be able to inhibit PHA-induced blood lymphocyte proliferation, as was shown for some other animal species. Finally, in an antibody-dependent cell-mediated cytotoxicity test (ADCC), SAM were shown to be inactive although swine blood monocytes were cytotoxic.