Effect of multiporous microspheres derived from chitin and partially deacetylated chitin on the activation of mouse peritoneal macrophages.

Multiporous microspheres were prepared from 80% deacetylated chitin (DAC-80) and chitin, and their effects on the activation of murine peritoneal macrophages in vivo and on the production of monokines such as colony-stimulating factor (CSF) and interleukin 1 (IL-1) were examined. Multiporous DAC-80 microspheres of mean diameter 2.5 microns [MS-DAC-80(2.5)] enhanced the cytolytic activity of peritoneal macrophages and the production of CSF in vitro by macrophages, spleen cells and bone marrow cells, and in vivo. MS-DAC-80(2.5) also stimulated the production of IL-1 by both resident and thioglycolate-induced peritoneal macrophages. Multiporous chitin microspheres [MS-chitin(2.5)] showed no effect on the activation of peritoneal macrophages in vivo and on the production of IL-1 in vitro, but slightly enhanced the production of CSF in serum in vivo.