Schoenbeck S, McKenzie D T, Kagnoff M F
Department of Medicine, University of California, San Diego 92093.
Eur J Immunol. 1989 Jun;19(6):965-9. doi: 10.1002/eji.1830190602.
Interleukin 5 (IL5) stimulates murine B cells to IgA production in vitro. The present study examined the B cell target of IL5 activity, and asked whether IL5 acts as an isotype switch factor, a growth factor, or a differentiation factor on B cells that produce the IgA isotype. Lipopolysaccharide-activated surface IgM-positive, surface IgA-positive or surface IgA-negative B cell populations from spleen or Peyer's patches were stimulated with IL5, after which the expression of cell surface IgA, IgA secretion, and numbers of IgA-secreting cells were determined. IL5 increased the IgA response by acting on B cells that are already committed to IgA expression. Thus, with regard to the IgA response, IL5 acts as a differentiation factor, rather than a growth or IgA isotype switch factor.
白细胞介素5（IL5）在体外刺激小鼠B细胞产生IgA。本研究检测了IL5活性的B细胞靶点，并探讨IL5对产生IgA同种型的B细胞是作为同种型转换因子、生长因子还是分化因子发挥作用。用IL5刺激来自脾脏或派伊尔结的经脂多糖激活的表面IgM阳性、表面IgA阳性或表面IgA阴性B细胞群体，然后测定细胞表面IgA的表达、IgA分泌以及IgA分泌细胞的数量。IL5通过作用于已致力于IgA表达的B细胞来增强IgA反应。因此，就IgA反应而言，IL5作为一种分化因子，而非生长因子或IgA同种型转换因子发挥作用。
