Concerted Activity of IgG1 Antibodies and IL-4/IL-25-Dependent Effector Cells Trap Helminth Larvae in the Tissues following Vaccination with Defined Secreted Antigens, Providing Sterile Immunity to Challenge Infection
Fig 4
Vaccine-induced immunity requires IL-4R-mediated signaling but not eosinophils, mast cells, basophils or CCR2+ monocytes.
A-F. Day 21–28 worm counts in control and vaccinated (A) C57BL/6 and IL-4Rα–/– mice, (B-C) BALB/c and GATA-1 Δdbl mice, (D) ACK-2-treated and control C57BL/6 mice, (E) C57BL/6 4get/Mcpt8 cre and 4get controls and (F) CCR2–/– and C57BL/6 controls. n.b. PBS/alum immunized CCR2–/– mice died or were culled between 7–9 days post-challenge, with significant intestinal bleeding observed. Luminal worms in (A, B, D, E, and F), whereas counts in (C) represent live worms recovered from the intestinal wall at day 21 (i.e. presumed non-migratory parasites). Data in (A, B, C, E and F) pooled from 2 independent experiments. Significance in (A), (C) and (D) determined by ANOVA, in (B) by Kruskal-Wallis test, and (E-F) by unpaired t-test. See also S3 Fig.