Figure 1.

Maternal antibiotic treatment (MAT) effector CD8⁺ T cells exhibit less polyfunctional cytokine responses than control (CTRL) effector cells. Congenic (CD454.1) OT-I CD8⁺ T cells isolated from the spleens of day of life 15 CTRL and MAT infant mice were adoptively transferred into age- and gender-matched CTRL Rag1KO recipient mice 24 h prior vaccinia-OVA infection (1 × 10⁴ PFU intraperitoneal). Lymphocytes isolated from the spleen, mesenteric lymph nodes (MLN), and peritoneal exudate cells (PEC) of CTRL Rag1KO recipient mice were analyzed for (A) percentage of CD45.1 and T cell receptor (TCR) Vβ5⁺ cells of total lymphocytes, (B) percentage of CD44⁺ and CD62L⁻ cells (T effector cells, Teff) of OT-I CD8⁺ T cells, (C) percentage of CD69⁺ cells of OT-I Teff cells, (D) median fluorescence intensity (MFI) of CD69 of OT-I Teff cells, and (E) percentage of interferon gamma (IFN-γ)- and TNF-α-expressing OT-I Teff cells following in vitro stimulation with SIINFEKL peptide (5 μM). DN, double negative for IFN-γ and TNF-α expression. Collated data from two independent experiments are shown (CTRL, n = 7; MAT, n = 10). Data in panels (A–C) are presented as mean + SEM. *p < 0.05, unpaired two-tailed Student’s t-test.