Dieye T N, Ndiaye O, Ndiaye A B, Thiam D, Fall-Seck K, Diop S, Diop B M, Fall M, Diakhaté L
Centre National de Transfusion Sanguine (CNTS), Dakar.
Dakar Med. 1999;44(2):175-9.
Sickle cell disease is an hereditary hemoglobinopathy syndrome which provokes deglobulization crisis and infectious complications. These infectious diseases may be due to a permanent activation of the immune system. The aim of our study was to explore alternative pathway by measuring C3 complement and the classical pathway by C4 complement. The level of immunoglobulins IgA, IgG and IgM was also measured in the subjects sera. Thirty homozygous sickle cell anemia (SS), 25 heterozygous (AS) and 34 controls subjects (AA) were recruited in the Hôpital d'Enfants Albert Royer (HEAR), Fann hospital and Centre National de Transfusion Sanguine (CNTS). Radial Immunodiffusion (RID) technics using specific antisera for C3c, C4c, IgA, IgG and IgM were used in our study. Homozygous SS proved an increase level of IgA (50%, p < 0.003) and IgG (47%, p < 0.003), unlike of IgM level. The C3c complement decrease significantly in (27%) of homozygous SS patients (p < 0.0005) unlike of C4c level. This low level of C3 and IgG in sickle cell homozygous patients can explain the higher susceptibility to infection in these patients. Normal level of C4 and low level of C3 show activation of alternative pathway. Heterozygous AS showed a normal level of C4, C3 and immunoglobulins. Our results suggests a direct involvement of the complement system in sickle cell disease and the depletion of C3 registered was a possible cause of increased susceptibility to infections in patients with homozygous sickle cell anemia.
镰状细胞病是一种遗传性血红蛋白病综合征，可引发血红蛋白溶解危机和感染性并发症。这些传染病可能是由于免疫系统的持续激活所致。我们研究的目的是通过测量C3补体来探索替代途径，并通过C4补体来探索经典途径。还对受试者血清中的免疫球蛋白IgA、IgG和IgM水平进行了测量。在阿尔贝·罗耶儿童医院（HEAR）、法恩医院和国家输血中心（CNTS）招募了30名纯合子镰状细胞贫血（SS）患者、25名杂合子（AS）患者和34名对照受试者（AA）。我们的研究使用了针对C3c、C4c、IgA、IgG和IgM的特异性抗血清的放射免疫扩散（RID）技术。与IgM水平不同，纯合子SS患者的IgA水平升高（50%，p<0.003），IgG水平升高（47%，p<0.003）。与C4c水平不同，纯合子SS患者中27%的C3c补体显著降低（p<0.0005）。镰状细胞纯合子患者中C3和IgG水平较低可以解释这些患者对感染的易感性较高。C4水平正常而C3水平较低表明替代途径被激活。杂合子AS患者的C4、C3和免疫球蛋白水平正常。我们的结果表明补体系统直接参与了镰状细胞病，而记录到的C3消耗可能是纯合子镰状细胞贫血患者易感性增加的原因。
