Abstract

It is well known that the murine T helper cell clones are divided by their lymphokine secretory activities. One is the Th-1 cell, producing IL-2 and IFN after stimulation and the other is the Th-2 cell, producing the IL-4 and IL-5. This study was undertaken to evaluate the immunomodulatory properties of the bacterial lipopolysaccharide(LPS) on the lymphokine production in vivo and in vitro. The results were as follows: There were no effects on the lymphokine secretion by the in vitro treatment of the LPS. The in vivo treatment of the LPS decreases the capability of the production of IL-2 and IFN , whereas it increases the capability of IL-4 production. The altered capacity of the lymphokine production was recovered about 2 weeks after the treatment of the LPS. There were no differences on the lymphokine production between E-coli LPS and salmonella LPS. The capacity of the lymphokine production was the same in the treatment of a non-heated LPS or heated-LPS. The lymphokine production of the mice which were desensitized by the long term treatment of the LPS was not different from the control mice. The in vitro treatment of RU486 can block the alterations of the lymphokine production after the treatment of the LPS. In summary, one can tell that the LPS increases the secretion of the IL-4 through the endogenous secretion of the glucocorticoids.

• Keywords: LPS;Lymphokine;T lymphocyte