Umetsu D T, Leung D Y, Siraganian R, Jabara H H, Geha R S
J Exp Med. 1985 Jul 1;162(1):202-14. doi: 10.1084/jem.162.1.202.
Human T cell helper/inducer clones were used to induce IgE synthesis in B cells from both allergic and nonallergic donors. An alloreactive T cell clone, activated by recognition of specific HLA-DR antigens, stimulated peripheral blood B cells from both allergic and nonallergic donors to synthesize IgE antibody. B cells of allergic donors differed from those of nonallergic donors in their requirements for induction of IgE synthesis. Induction of IgE synthesis in B cells from nonallergic individuals occurred only under conditions of cognate interaction, in which the B cells expressed the alloantigen recognized by the T cells. In contrast, IgE synthesis in B cells from allergic donors occurred under conditions of cognate interaction with T cells as well as bystander conditions where the B cells did not express the alloantigen recognized by the T cell clones and where the T cell clones were stimulated by third-party monocytes bearing the relevant alloantigens. Furthermore, bystander stimulation of IgE synthesis in allergic donors occurred in the presence of tetanus toxoid (TT) antigen-specific T cell clones activated by the appropriate TT-pulsed monocytes. In contrast to the differing requirements of B cells from normal vs. allergic subjects for the induction of IgE synthesis, these B cells did not differ in their requirements for the induction of IgG synthesis. IgG synthesis was induced in all B cells under conditions of cognate interaction with the T cells as well as under conditions of bystander stimulation. These results suggest that cognate T-B cell interactions may be important in the development of IgE immune responses in the normal host.
人类T细胞辅助/诱导克隆被用于诱导来自过敏和非过敏供体的B细胞合成IgE。一个同种异体反应性T细胞克隆，通过识别特定的HLA-DR抗原而被激活，可刺激来自过敏和非过敏供体的外周血B细胞合成IgE抗体。过敏供体的B细胞与非过敏供体的B细胞在诱导IgE合成的需求方面存在差异。非过敏个体B细胞中IgE合成的诱导仅在同源相互作用的条件下发生，即B细胞表达T细胞识别的同种异体抗原。相比之下，过敏供体B细胞中的IgE合成在与T细胞同源相互作用的条件下以及旁观者条件下都会发生，在旁观者条件下，B细胞不表达T细胞克隆识别的同种异体抗原，且T细胞克隆由携带相关同种异体抗原的第三方单核细胞刺激。此外，在由适当的破伤风类毒素（TT）脉冲单核细胞激活的TT抗原特异性T细胞克隆存在的情况下，会发生对过敏供体中IgE合成的旁观者刺激。与正常和过敏受试者的B细胞在诱导IgE合成方面的不同需求相反，这些B细胞在诱导IgG合成的需求方面没有差异。在与T细胞同源相互作用的条件下以及旁观者刺激的条件下，所有B细胞都会诱导IgG合成。这些结果表明，同源T-B细胞相互作用可能在正常宿主中IgE免疫反应的发展中起重要作用。
