Figure 6
Cells from Tlr4−/− mice have an impaired immunoglobulin A (IgA) transcytosis response to lipopolysaccharide (LPS) but not interleukin-17 (IL-17). (a and c) Wild-type (WT) Tlr4 and Tlr4−/− were treated with 10 μM DAPT (N-[N-(3,5-difluorophenacetyl-L-alanyl)]-S-phenylglycine t-butyl ester) and 1 μg ml−1 LPS. (a) IgA transcytosis was measured by enzyme-linked immunosorbent assay (ELISA) and results were normalized to the WT group (=100%). Values are indicated as mean±s.e.m.; n=8 per group. Wilcoxon’s signed-rank test: ***P=0.0039. (b and d) WT Tlr4 and Tlr4−/− cells were treated with 10 μM DAPT and varying doses of IL-17. (b) IgA transcytosis was analyzed by ELISA and results were normalized to the WT+D+L group (=100%). (c and d) Gene expression analysis of polymeric Ig receptor (pIgR) was performed, and all samples were normalized to glyceraldehyde 3-phosphate dehydrogenase. Data are presented as fold change relative to untreated (0% conditioned media) cells. All values are indicated as mean±s.e.m. One-way analysis of variance: (b) F=116.9, P<0.0001, n≥3 per group; (c) F=40.92, P<0.0001, n≥7 per group; and (d) F=6.364, P<0.0004, n≥3 per group. Means with different letters are significantly different by Bonferroni’s multiple comparison test.
