Figure 4. The depletion of the intestinal flora reduces the severity of the immune phenotype.

The microbiota of 1-year-old WT and sPLA₂-IIA^TGN mice housed in an Elite SPF+ animal facility was depleted using broad-spectrum antibiotics for 6 weeks prior to assessment of the immune phenotype. (A) Weight of MDLNs following antibiotic treatment (n = 10). (B–E) Flow cytometric analysis with markers targeting T cells (CD3⁺CD19^–), B cells (CD19⁺CD3^–), and granulocytes (Gr1⁺) (n = 5). T lymphocyte and B lymphocyte counts in MDLNs are shown, and the proportion of granulocytes in the BM and spleen of WT and sPLA₂-IIA^TGN mice treated or not with antibiotics is displayed. (F) Dosage of IL-17A by cytometric bead array in the serum of all mouse groups (n = 5). (G and H) Concentration of sPLA₂-IIA quantified by time-resolved fluoroimmunoassay in serum and intestinal lysates of sPLA₂-IIA^TGN mice treated or not with antibiotics (n = 5). Data from 1 experiment are presented as mean ± SEM. Statistical analysis included 1-way ANOVA with Dunnett’s multiple comparisons test. *P < 0.05, **P < 0.01, ****P < 0.0001.