Spitzer R E, Stitzel A E, Tsokos G C
Department of Pediatrics, Health Science Center, State University of New York, Syracuse 13210.
Clin Immunol Immunopathol. 1990 Oct;57(1):10-8. doi: 10.1016/0090-1229(90)90018-l.
To understand the origin of autoantibody production, we studied the ontogeny of antibody to the alternative pathway C3 convertase (C3 nephritic factor or C3NeF). Peripheral blood mononuclear cells from newborns, normal adults, and patients with membranoproliferative glomerulonephritis produced IgM and IgG C3NeF after culture for 14 days with pokeweed mitogen. Both IgM and IgG moieties appear to have the same paratope and are able to inhibit each other's binding and function. The affinity constant for each of the C3NeF molecules was moderately high (10(8) liters/mol) and there appeared to be little difference between the Ka values for the IgG and the IgM autoantibodies or between Ka values for autoantibodies isolated from newborns, adults, and patients. These data, then, indicate that the ability to produce C3NeF autoantibody is present from the time of birth in normal individuals. The high affinity of these autoantibodies under normal conditions suggests that C3NeF may play a more important physiological role than previously anticipated.
为了解自身抗体产生的起源，我们研究了针对替代途径C3转化酶（C3肾炎因子或C3NeF）抗体的个体发生。新生儿、正常成年人和膜增生性肾小球肾炎患者的外周血单个核细胞在与商陆有丝分裂原培养14天后产生IgM和IgG C3NeF。IgM和IgG部分似乎具有相同的抗原决定部位，并且能够相互抑制彼此的结合和功能。每个C3NeF分子的亲和常数适中偏高（10⁸升/摩尔），并且在IgG和IgM自身抗体的Ka值之间或从新生儿、成年人和患者分离的自身抗体的Ka值之间似乎几乎没有差异。这些数据表明，正常个体从出生时就具备产生C3NeF自身抗体的能力。在正常条件下这些自身抗体的高亲和力表明C3NeF可能发挥比先前预期更重要的生理作用。
