Preparations of lipopolysaccharide (LPS) from rough and smooth strains of Brucella abortus were mitogenic for spleen cells of athymic nude mice, C3H/HeAU mice, and the endotoxin-resistant C3H/HeJ mice. The mitogenic response induced by crude smooth-LPS (f5) was greater than that produced by purified smooth-LPS (f5p); however, the dose-response curves were similar for both preparations. The mitogenic activity of mouse spleen cells to both f5 and f5p was higher than that produced by stimulation with purified rough-LPS. The dose-response curves with rough-LPS were also qualitatively different from those produced with the preparations of smooth-LPS.
This work was supported by the College of Agricultural and Life Sciences, by cooperative Agreements with the United States Department of Agriculture, Animal and Plant Health Inspection Service, and the Science and Educational Administration, and by a grant from Consejo Nacional de Investigaciones Cientificas y Tecnologicas (CON-ICIT) de Costa Rica.