Fig. 2

Infection burden affects the strength of the innate immune response. a Normalized fluorescence ratio for worms infected for 18 h with the indicated dilutions of a solution of fresh D. coniospora spores, compared to non-infected (NI) worms. In each sample, a minimum of 230 worms was analyzed. The bar indicates the mean value. Since spore virulence depends on the age of the spores and of the plate from which they were harvested [121], the absolute spore concentration is not an informative measure and is not shown here. Comparisons between selected conditions are shown (Mann–Whitney test); ns, not significant; * P < 0.05; *** P < 0.001; **** P < 0.0001. b–e. Comparison at lower (b, d) and higher (c, e) magnification between worms treated with a control RNAi (sta-1; b, c) or RNAi against bus-12 (d, e). In contrast to the control worms, bus-12(RNAi) animals exhibited a very markedly increased adhesion of spores (white arrows) over the entire body (c), prominently at the head and tail (e). Scale bar in b and d: 50 μm