In vivo production of various cytokines in splenocytes of sheep erythrocyte-immunized mice after intravenous administration of bacterial lipid A.
The effects of an intravenous administration of lipid A from Salmonella minnesota R595 lipopolysaccharide on the in vivo production of interleukin-2 (IL-2), IL-4, IL-5 and IL-6 in the spleens of mice intravenously immunized with sheep red blood cell (SRBC) antigen were investigated. The increased number of antigen-specific IgM antibody-producing cells and the titer of the IgM serum antibody were measured using the plaque-forming cell (PFC) assay and an enzyme-linked immunosorbent assay (ELISA). Simultaneous injections of SRBC antigen and lipid A adjuvant enhanced IgM-PFC number on days 3 and 4 and the serum IgM titer on days 4 and 5 after the immunization. We found that the enhanced IL-4 and IL-5 levels correlated with the PFC number and IgM titer. When lipid A was injected intravenously 2 days after immunization with SRBC, the PFC number in lipid A-treated groups were similar to those in controls 3 and 4 days after the immunization. However, it was found that a twofold increase in the IgM titer in serum was induced by lipid A 5 days after immunization. In relation to this increase, lipid A stimulated the production of only IL-5 among the cytokines tested.
Mashimo
J
J
Department of Microbial Chemistry, School of Pharmaceutical Sciences, Showa University, Tokyo, Japan.
Mita
A
A
D000818:Animals; D000921:Antibody-Producing Cells / Q000276:immunology; D004797:Enzyme-Linked Immunosorbent Assay; D004912:Erythrocytes / Q000276:immunology*; D006462:Hemolytic Plaque Technique; D007114:Immunization; D007075:Immunoglobulin M / Q000032:analysis; D007275:Injections, Intravenous; D007378:Interleukins / Q000096:biosynthesis*; D008050:Lipid A / Q000008:administration & dosage / Q000276:immunology*; D008297:Male; D051379:Mice; D008813:Mice, Inbred ICR; D012475:Salmonella; D012756:Sheep; D013154:Spleen / Q000166:cytology / Q000276:immunology* / Q000378:metabolism; D013997:Time Factors
D007075:Immunoglobulin M; D007378:Interleukins; D008050:Lipid A