Sjöholm A G, Hallberg T, Oxelius V A, Hammarström L, Smith C I, Lindgren F
Acta Paediatr Scand. 1987 May;76(3):533-8. doi: 10.1111/j.1651-2227.1987.tb10514.x.
C2 deficiency was demonstrated in an 11-year-old boy with a past history of recurrent purulent otitis media, pneumonia, H. influenzae meningitis and S. pneumoniae septicaemia. The major histocompatibility complex haplotypes present, A10, B18, DR2, BFS, C2QO, C4A4, C4B2 and A28, B18, DR2, BFS, C2Q0, C4A4, C4B2, were in accord with previous observations in C2 deficiency. The concentrations of C1q, C5, factor B and factor D were in the low normal range and the hemolytic activity of the alternative pathway was slightly decreased. In addition, the patient showed moderately low IgG2 concentrations and lacked the IgG2 subclass marker G2m(23). The findings indicate that the patient's susceptibility to bacterial infections may be due to C2 deficiency in combination with the presence of an IgG allotype associated with impaired antibody responses to carbohydrate antigens.
在一名11岁男孩身上证实了C2缺陷，该男孩既往有复发性化脓性中耳炎、肺炎、流感嗜血杆菌脑膜炎和肺炎链球菌败血症病史。所呈现的主要组织相容性复合体单倍型，即A10、B18、DR2、BFS、C2QO、C4A4、C4B2以及A28、B18、DR2、BFS、C2Q0、C4A4、C4B2，与先前在C2缺陷中的观察结果一致。C1q、C5、B因子和D因子的浓度处于低正常范围，替代途径的溶血活性略有降低。此外，该患者的IgG2浓度中度偏低，且缺乏IgG2亚类标志物G2m(23)。这些发现表明，患者对细菌感染的易感性可能是由于C2缺陷以及存在与碳水化合物抗原抗体反应受损相关的IgG同种异型。
