Fig. 3.

Cytokine production by cord blood mononuclear cells (CBMC) in response to phytohaemagglutinin (PHA). CBMC from newborns whose mothers had malaria infection of the placenta at delivery (black bars, n = 21) or were free of infection (grey bars, n = 34) were cultured for 3 days with PHA and assessed for their cytokine production and sCD30 release. T helper type 1 (Th1) [interferon (IFN)-γ] and Th2 (sCD30) markers, as well as the anti-inflammatory cytokine interleukin (IL)-10 were measured using enzyme-linked immunosorbent assay (ELISA). Measurements were made with (+) or without (−) CD4⁺CD25⁺ regulatory T cell depletion. As already reported [4], significantly less IFN-γ was produced by CBMC obtain from the group with parasitized placenta (P2 = 0·003), while the levels of the Th2 markers were similar between groups. Higher IL-10 levels were produced by cells from the parasitized placenta group (P5 = 0·025). Depletion of regulatory T cells decreased IL-10 production in cells from both groups (p3 = 0·028, p4 = 0·035) and restored IFN-γ production (p1 = 0·02). Results are shown as mean ± standard error of the mean.