Effect of vaccination on local and systemic Treg frequency in mice.

Abstract

<p>At day 0, mice were i.m. injected with LPS, CFA or with one of the vaccines (TIV⁺, TIV^- and Engerix-B^®). Mock-injected animals received PBS. At day 3, 7, 14 and 21 post vaccination changes in Treg frequency were determined. The delta Treg percentage per time point was determined by comparing the treatment with the mean of PBS (= % Treg treatment day_x—average % Treg PBS day_x). The mean percentage Treg in PBS-injected mice was 10.9 ± 1.4% (dLN) and 12.0 ± 1.5% (spleen). N = 3–7 mice per group. <b>(A-D)</b> Mean (± SEM) delta percentage of Treg (CD4⁺ CD25⁺ Foxp3⁺) frequency at the different time points after vaccination were analyzed in dLN (A and C) and spleen (B and D) after LPS injection (A and B) and CFA or vaccine injection (C and D). Differences between PBS and LPS (A and B) were determined with an unpaired two-tailed student’s t-test with Welch’s correction. Differences between PBS and vaccines (C and D) were determined with a one-way ANOVA followed by Dunnett’s multiple comparisons test (* p < 0.05, ** p < 0.01, *** p < 0.001 relative to PBS at the same time point). TIV⁺: TIV supplemented with MF59^® adjuvant; TIV^-: TIV only; ENG: Engerix-B^®</p