Fig. 4.

There is a lack of host immune reactivity to p43, although p43 is successfully able to vaccinate mice against infection. a, b Anti-mouse Ig (G, M, and A) enzyme-linked immunosorbent assay (ELISA) using serum from infected C57BL/6 mice. a Day 35 post infection (p.i.) serum from mice given a high-dose T. muris infection. b Serum from C57BL/6 mice 55 days p.i. earlier (E/S-D55-LD) or repeated low-dose (trickle) T. muris infections (day 0, 2, 4, 7, 9, and 11) at day 35 p.i. ELISA plates were coated with whole T. muris E/S, native p43, or E/S−^p43, and serum was diluted at 1/80. c Interleukin-13 (IL-13) cytokine production from mesenteric lymph node cells (MLNCs) from mice infected with 200 T. muris eggs and culled at day 21 p.i. d Interferon-γ (IFN-γ) production from MLNCs from mice infected with 20 T. muris eggs and culled at day 21 p.i. In both assays, cells were restimulated with whole E/S, native p43, or ES^−p43. e Worm burdens of mice at 35 days p.i. Mice were vaccinated with 50 μg of p43, or E/S^−p43 subcutaneously with alum or with alum alone (vaccination control) on day −28 and day −14 p.i. and infected at day 0 with 20 T. muris eggs. Data in a–e have been repeated at least 3 times and n = 5. Data from noninfected controls were below the detectable limits of the assay for data shown in a–d. All data are presented as mean ± SEM. A one-way analysis of variance (ANOVA) was used to analyze the data, a F value = 5.494, DF = 12, E/S vs. p43, *p = 0.0330, p43 vs. E/S^−p43, *p = 0.0370; b F = 58.25, DF = 24, E/S-D55-LD vs. p43-LD-D55; E/S-Trickle vs. p43-Trickle; p43-LD-D55 vs. E/S^−p43-LD-D55 and p43-Trickle vs. E/S-p43-Trickle, all ****p < 0.0001; c F = 7.577, DF = 12, E/S vs. p43, *p = 0.0135 and p43 vs. E/S^−p43, *p = 0.0150; d F = 156.8, DF = 27, E/S vs. p43 and p43 vs. E/S^−p43, ****p < 0.0001; e F = 24.27, DF = 12, vaccinated control + infected vs. vaccinated p43 and vaccinated control + infected vs. vaccinated E/S^−p43, ***p = 0.0002