抗体産生細胞の動態に関する研究

Abstract

Interleukin-2 (IL-2) is one of the cytokines regulating antibody formations. To examine the effect of IL-2 on lipopolysaccharide (LPS)-specific antibody secretion on the number of antibody secreting cells (ASC) were counted in the presence and absence of IL-2 in rat spleen cells culture. First we established the enzyme-linked immunospot (ELISPOT) assay, which is the method of determinating the number of ASC. Rat spleen cells with high and low concentrations of LPS (10 ng/ml and 10μg/ml) were incubated for 3 days in vitro, and the number of the LPS specific ASC were counted. In the culture incubated with high concentration (LPS 10 ng/ml) the number of ASC is higher than that in the culture with low concentration LPS 10μg/ml, it is obious that the appearance of ASC depended on LPS concentrations. Supprisingly addition of IL-2 decreases the number of ASC at low concentration of LPS (10 ng/ml), but it increases that at high concentration of LPS (10μg/ml). Thus opposite effect of IL-2 was observed at different LPS concentrations. It is well-known that IL-2 enhances antibody formation in the presence of antigen. But it is strange that IL-2 suppressed antibody formation in the presence of antigen, in the case of low concentration of LPS.