T cell regulation of the antibody response to bacterial polysaccharide antigens: an examination of some general characteristics and their implications.

The characteristics of thymus-derived (T) lymphocytes that regulate the magnitude of the antibody response to the capsular polysaccharide antigen of type III Streptococcus pneumoniae are considered within the context of a general homeostatic model for controlling the antibody response to microbial antigens of medical importance. Some experimental approaches are described in which the activities of such regulatory T cells are modulated to provide an increase in the development of host immunity, to improve the immunogenicity of poorly immunogenic antigens, or to eliminate the inhibitory effects of suppressor T cells.