A Decline in p38 MAPK Signaling Underlies Immunosenescence in Caenorhabditis elegans
(A) Survival of wild type strain N2 transferred from E. coli OP50 to P. aeruginosa PA14 at L4 (orange), Day 3 (magenta), Day 6 (blue), or Day 9 (green) plotted as fraction of worms alive versus time. (B) Accumulation of P. aeruginosa within the intestinal lumen of C. elegans at ∼24 h post-infection. Wild type N2 strain late larval stage (L4) and adult worms were infected with a strain of P. aeruginosa that expresses GFP and then scored the next day according to the extent of bacterial colonization of the intestine. The pattern of P. aeruginosa infection in individual animals was classified as either “None” when no GFP-expressing P. aeruginosa could be detected in the intestine, “Partial” when P. aeruginosa colonization of the intestine was incomplete or was localized to a bolus, or “Full” when the intestinal lumen was completely packed with bacteria along its entire length.