T independent antigen


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T independent antigen

Either of two types of antigens that stimulate B cell production of antibodies without the presence of T cells. TI-1 antigens (e.g., lipopolysaccharides from gram-negative organisms) stimulate production of both specific (monoclonal) and nonspecific (polyclonal) antibodies and promote the release of cytokines from macrophages that enhance the immune response. TI-2 antigens, which result in monoclonal antibody production, may require the presence of cytokines. See: B cell; T cell
See also: antigen