Figure 3.

Azithromycin (AZM) treatment at 7 days post Bordetella pertussis challenge modulates induction of T cell and antibody responses. CD4 T cells in lung digests were characterized by flow cytometry. The percentage of IL-17-producing cells in the CD4 population was analyzed via intracellular cytokine staining 3 and 14 days after treatment. Representative dot plots of the CD4⁺ population are shown (A). T_EM (CD62L^low CD44⁺) (C) and tissue-resident memory T (T_RM) (CD62L^low CD44⁺ CD69⁺ CD103⁺) (D) were analyzed 3 and 14 days after treatment. (B) Upper panels show representative dot plots of the CD4⁺ population on day 10, lower panels show representative dot plots of the T_EM population on day 10. Splenocytes were obtained 28 days post challenge (dpc) and stimulated with filamentous hemagglutinin (FHA) or sBP for 72 h. IFN-γ (E) and IL-17 (F) production in the supernatants were determined via ELISA. Serum was collected from mice on 28 dpc and FHA-specific total IgG serum titers were determined via ELISA (G). (A,C–G) Horizontal lines indicate mean. Significances were determined via t-test, *p < 0.05, **p < 0.01, ***p < 0.001.