Loss of regulation of complement C5 activation in HIV associated Preeclampsia

ObjectiveMaternal mortality remains a global health concern in developing countries that are also affected by HIV infection. Complement components are anaphylatoxin that mediate several growth factors necessary during pregnancy. An extensive stimulation of the complement system contributes to the pathogenesis of preeclampsia; hence its inhibition facilitates a successful pregnancy. The study evaluated the expression of complement components C2 and C5a in HIV and the association with preeclampsia. Materials and MethodsSerum samples were collected from 76 pregnant women of which 38 were preeclamptic and 38 normotensive pregnant. The participants were further stratified according to HIV infection status. Bio-Plex multiplex immunoassay method was used to quantify serum concentration of C5a and C2 complement components. ResultsThe C2 complement concentration was not significantly different between preeclamptic and normotensive pregnant women, irrespective of HIV status as well as pregnancy type. However, based on preeclamptic vs normotensive pregnancy type, the expression of C5a was significantly different (p = 0.05). The C5a levels were downregulated in preeclampsia compared to normotensive women, irrespective of HIV status. Both C2 and C5a concentrations did not differ across all study groups. ConclusionThis novel study reports a loss of regulation of complement activation shown by the downregulation of C5a in preeclamptic compared to normotensive pregnant women, regardless of HIV status. Complement dysregulation affects the host innate defence, and as a consequence, intensifies placental and fetal injury. Moreover, HIV status did not influence the expression of both C5a and C2, irrespective of pregnancy type, this may be attributed to Highly Active Antiretroviral Therapy.