Fig. 4

P. falciparum- induced pro-inflammatory cytokine production enhanced after period of minimal exposure. Peripheral blood mononuclear cells isolated from children with little current exposure to malaria (Blue bars, Ngerenya, n = 15), continually exposed children (Red bars, Junju, n = 15), and malaria-naïve children (Black bars, n = 5) were stimulated for 7 days with P. falciparum-infected or uninfected red blood cells (iRBC or uRBC). Culture supernatants were collected and analyzed using a multiplex assay for 25 cytokines. P. falciparum-specific cytokine production was calculated as concentration of cytokine following iRBC stimulation minus uRBC stimulation. Results are shown for cytokines which were detected at a net concentration ≥ 40 pg/mL. a Concentration of P. falciparum-induced CCL2 in each group. b Concentration of P. falciparum-specific IL-6, CCL5, CCL3, CCL4, IL-1RA, CXCL10, and CXCL9 in each group. Bars indicate mean cytokine concentration (pg/mL) with standard error of the mean (SEM) also indicated. Statistically significant differences (*P < 0.05, **P < 0.01) are indicated by asterisk (in red for Kruskal–Wallis or black for Mann–Whitney U-tests, respectively)