Dziarski R
Immunology. 1987 Jun;61(2):111-6.
Modulation of activation of polyclonal IgM, IgG and IgM anti-DNA antibodies by plasma fibronectin (Fn) was studied because in some autoimmune diseases there appears to be a correlation between the increased level of Fn in the affected tissues and increased polyclonal B-cell activation. Fn caused a dose-dependent polyclonal activation of IgM, IgG and IgM anti-DNA antibody-secreting cells in cultures of mouse splenocytes. Fn significantly inhibited the generation of polyclonal antibodies by Fn-binding stimulants and did not significantly change the generation of polyclonal antibodies by the stimulants that do not bind Fn. Plasmin or trypsin digestion of Fn abolished both the polyclonal activating properties of Fn and the inhibitory effects of Fn that were selective for the Fn-binding polyclonal activators. Digestion of Fn with trypsin also generated immunosuppressive Fn fragments that inhibited polyclonal activation by both Fn-binding and non-binding bacteria. Under our culture conditions Fn or Fn digests were not mitogenic and had no effect on the mitogenicity of Fn-binding and non-binding stimulants. These results indicate that Fn can act as a polyclonal activator and that it can also modulate lymphocyte activation induced by other activators.
研究了血浆纤连蛋白（Fn）对多克隆IgM、IgG和IgM抗DNA抗体激活的调节作用，因为在一些自身免疫性疾病中，受累组织中Fn水平的升高与多克隆B细胞激活增加之间似乎存在关联。在小鼠脾细胞培养物中，Fn引起了IgM、IgG和分泌IgM抗DNA抗体细胞的剂量依赖性多克隆激活。Fn显著抑制了与Fn结合的刺激剂诱导的多克隆抗体的产生，并且对不与Fn结合的刺激剂诱导的多克隆抗体的产生没有显著影响。用纤溶酶或胰蛋白酶消化Fn消除了Fn的多克隆激活特性以及Fn对与Fn结合的多克隆激活剂的选择性抑制作用。用胰蛋白酶消化Fn还产生了免疫抑制性Fn片段，该片段抑制了与Fn结合和不与Fn结合的细菌诱导的多克隆激活。在我们的培养条件下，Fn或Fn消化产物没有促有丝分裂作用，并且对与Fn结合和不与Fn结合的刺激剂的促有丝分裂作用没有影响。这些结果表明，Fn可以作为一种多克隆激活剂，并且它还可以调节由其他激活剂诱导的淋巴细胞激活。
