Filarial Parasites Develop Faster and Reproduce Earlier in Response to Host Immune Effectors That Determine Filarial Life Expectancy
(A) When co-inoculated with eosinophilia-inducing rIL-5 and L3 parasites, BALB/c mice became microfilaraemic sooner than in control infections as suggested by the proportion of mice presenting blood circulating microfilariae by D55 p.i. (p = 0.08, Fisher's exact test, n = 17, analysis restricted to mice that became microfilaraemic). (B) Early rIL-5-induced eosinophilia resulted in increased microfilaraemia throughout patency (effect of treatment on microfilaraemia p = 0.0001, negative binomial glm; n = 12, data points represent means ± s.e.m.) and a marginally earlier peak in microfilaraemia (occurring on day 68.5±1 and 72.8±2 in treated mice and controls, respectively, p = 0.09).