Dynamics of blood components and peritoneal fluid during treatment of murine E. coli sepsis with beta-1,3-D-polyglucose derivatives. I. Cells.

Beta-1,3-D-polyglucose derivatives protect mice against otherwise lethal bacterial infections. This protective effect has previously been considered to be mediated through mononuclear phagocytes. We have now investigated the cellular composition in blood and peritoneal fluid after administration of the beta-1,3-D-polyglucose before and after challenge with Escherichia coli. In animals treated with beta-1,3-D-polyglucose derivatives, the total white cell number was significantly increased in both blood and peritoneal fluid before and after challenge with E. coli. The increased total cell number was mainly the result of raised levels of granulocytes. The effects of beta-1,3-D-polyglucose-derivatized microbeads (GDM) and soluble aminated beta-1,3-D-polyglucose (AG) were similar. Bacterial counts in peripheral blood in GDM- and AG-treated animals increased with 6 h after challenge and approached zero after 24 h. In untreated animals the bacterial counts increased gradually until the animals died after about 12 h. Bacterial counts in peritoneal fluid of GDM- and AG-treated animals declined to zero after 24 h. In untreated animals there was a slight increase in bacterial counts until the animals died after about 12 h. By using radioactive labelling, we localized the bacterial as well as the beta-1,3-D-polyglucose derivatives during the period following injection. Particle-bound beta-1,3-D-polyglucose was recovered mainly in the milky spots of the omentum. A conspicuous number of bacteria were also recovered in the milky spots. The soluble aminated beta-1,3-D-polyglucose was recovered mainly in the liver. However, on a weight basis, the greatest concentration of radioactivity was in the milky spots.