Agnello V, Gell J, Tye M J
J Am Acad Dermatol. 1983 Dec;9(6):894-8. doi: 10.1016/s0190-9622(83)70205-7.
A high incidence of discoid lupus erythematosus (DLE) and urticaria/angioedema was found among patients with selective low levels of the C4 component of complement. Although evidence for activation of C4 was present in patients' sera, studies to determine the presence of known activation mechanisms were negative. Genetic C4 typing in four pedigrees showed that all propositi carried the null allele B*QO. It is postulated that the low C4 levels in these patients are related to the skin lesions and this partial genetic deficiency.
在补体C4成分选择性水平低下的患者中，发现盘状红斑狼疮（DLE）和荨麻疹/血管性水肿的发病率很高。尽管患者血清中存在C4激活的证据，但确定已知激活机制存在的研究结果为阴性。对四个家系进行的C4基因分型显示，所有先证者均携带无效等位基因B*Q0。据推测，这些患者的低C4水平与皮肤病变及这种部分基因缺陷有关。
