The reticuloendothelial stimulant glucan, a beta-1,3-polyglucose component of the cell wall of Saccharomyces cerevisiae, was evaluated for its ability to modify Staphylococcus aureus-induced lethality in normal and leukemic mice. In normal mice the intravenous injection of glucan (0.45 mg per mouse) 7 and 4 days prior to intravenous challenge with S. aureus (1.0 x 10(9)) resulted in a significantly increased survival. Histological examination of the kidneys revealed that glucan significantly inhibited renal necrosis associated with systemic staphylococcal diseases. Further studies indicated that glucan administration not only enhanced survival of leukemic mice, but also increased survival of leukemic mice with experimentally induced staphylococcal speticemia. These data denote that glucan enhances nonspecific resistance to S. aureus sepsis, promotes survival during leukemic episodes, and increases survival time of leukemic mice with experimentally induced staphylococcal infection.