VIPhyb, an Antagonist of Vasoactive Intestinal Peptide Receptor, Enhances Cellular Antiviral Immunity in Murine Cytomegalovirus Infected Mice
Figure 4
Blocking VIP-signaling increased cellular immune responses following mCMV infection.
VIP-KO (black dashed line with open circle) mice or WT littermate C57BL/6 mice treated with short-course of VIPhyb (10 µg/mouse s.c., gray dashed line with filled circle) or PBS (100 µL/mouse s.c., black solid line with filled circle) were infected with 1×105 PFU mCMV day 0 (one day after beginning treatment with VIPhyb or PBS). Mice were euthanized at 3, 10 and 17 days following mCMV infection and the spleens were isolated. Immune cells from the spleens were gated with CD3+, CD4+ or CD8+, and CD62L− and then phenotyped with CD25+CD69+ and specific anti-viral tetramer+ CD8+ T-cells by flow cytometry. A: Activated CD4+ T-cells. B: Activated CD8+ T-cells. Contour plots show data concatenated from 4 mice per time-point and per group, representative of 3 replicate experiments. C. Antigen-specific anti-viral T-cells. Data (mean ± SD, n = 24) summarized from 6 replicate experiments. Inserts: dot plots show data concatenated list mode files of four mice in the same group 7 days following mCMV infection, representative of 6 replicated experiments. D. Serum anti-mCMV antibody levels. Data (mean ± SD, n = 12 per time-point per group) summarized from 3 replicate experiments. E. Percentage of regulatory T-cells in the spleen from C57BL/6 mice pre mCMV infection (day 0) and 7 days following lower dose mCMV infection. Contour plots showed the concatenated list mode files from 5 mice per group 7 days following mCMV infection (mean ± SD), one representative of 2 replicated experiments. F. Percentage of CD3+ T-cells in spleen. G. Percentage of CD4+ T-cells in spleen. H. Percentage of CD8+ T-cells in spleen. *p<0.05, **p<0.01, and ***p<0.001 denote significant differences between VIP-KO mice or VIPhyb-treated mice vs. PBS-treated WT mice.