Endotoxin-Stimulated Spleen Cells: Mitogenesis, the Occurrence of the C3 Receptor, and the Production of Immunoglobulin

Abstract

Abstract Endotoxin (LPS)-stimulated mouse spleen cells were investigated in an attempt to correlate three markers for B lymphocytes: 1) LPS-induced blastogenesis, 2) rosette formation via the C3 receptor site, and 3) immunoglobulin production. After 24 hr stimulation 86% of LPS-induced blast cells formed rosettes indicating that these cells were B lymphocytes. Subsequently there was a progressive decrease in the percentage of rosette-forming blast cells to a low of 39% at 72 hr. The percentage of cells producing IgM increased progressively to a maximum of 54% after 72 hr of LPS stimulation These data indicate that at given times correlations between the three markers vary, and that no one of the three alone allows a strict categorization of cell types. The data presented are consistent with the hypothesis that LPS is a mitogen for B lymphocytes, although the possible involvement of other cell types was not ruled out.