Lynch D M, Kay P H, Papadimitriou J M, Grounds M D
Department of Pathology, University of Western Australia, Nedlands.
Eur J Immunogenet. 1993 Feb;20(1):1-9. doi: 10.1111/j.1744-313x.1993.tb00090.x.
Female SJL/J mice are more susceptible to development of experimental autoimmune myositis than most other mouse strains. Since complement has been implicated in the pathogenesis of inflammatory muscle disease in humans, quantitative and qualitative studies of complement C3 were undertaken in SJL/J and BALB/c mice to determine whether complement may influence disease susceptibility in SJL/J mice. In accordance with previous studies, mature male and female BALB/c mice were shown to have similar serum C3 concentrations. However, differences were found between mature male and female SJL/J mice. Male SJL/J mice have significantly higher serum C3 concentrations than SJL/J females and both sexes of BALB/c mice suggesting that serum C3 concentration may be variably influenced by sex in some mouse strains. Qualitatively, SJL/J mice were shown to have a different allotypic form of C3 (C3F) compared to the common electrophoretically slow form (C3S) found in BALB/c mice and most other mouse strains. Furthermore, studies on the decay rate of C3 revealed that C3b/iC3b fragments are converted to C3c/d at a faster rate in sera from female SJL/J mice compared to female BALB/c mice. Because removal and solubility of immune complexes is influenced by complement C3, it is possible that the more rapid decay of the phagocytic ligands C3b/iC3b may account for the increased susceptibility to development of autoimmune disease in female SJL/J mice.
雌性SJL/J小鼠比大多数其他小鼠品系更容易患实验性自身免疫性肌炎。由于补体与人类炎性肌肉疾病的发病机制有关，因此对SJL/J和BALB/c小鼠进行了补体C3的定量和定性研究，以确定补体是否可能影响SJL/J小鼠对疾病的易感性。与先前的研究一致，成熟的雄性和雌性BALB/c小鼠血清C3浓度相似。然而，在成熟的雄性和雌性SJL/J小鼠之间发现了差异。雄性SJL/J小鼠的血清C3浓度明显高于SJL/J雌性小鼠和BALB/c小鼠的两性，这表明血清C3浓度在某些小鼠品系中可能受到性别的不同影响。在定性方面，与BALB/c小鼠和大多数其他小鼠品系中常见的电泳慢型（C3S）相比，SJL/J小鼠显示出不同的C3同种异型形式（C3F）。此外，对C3衰变率的研究表明，与雌性BALB/c小鼠相比，雌性SJL/J小鼠血清中C3b/iC3b片段转化为C3c/d的速度更快。由于免疫复合物的清除和溶解性受补体C3影响，吞噬配体C3b/iC3b更快的衰变可能是雌性SJL/J小鼠自身免疫性疾病易感性增加的原因。
