Figure 3

Intravenous immunoglobulin injection modulates the relative populations of T lymphocytes. Flow cytometry analyses on splenocytes labeled for regulatory (CD4⁺, CD25⁺ and Foxp3⁺) iCOS⁺CD4⁺ (CD62L low, CD4⁺, iCOS⁺ and Foxp3⁺), helper (CD4⁺) and cytotoxic (CD8⁺) T cells. (A) Representative plots showing regulatory T cell (Treg; upper panels, gated on CD4⁺ cells) iCOS⁺CD4⁺ (middle panels, gated on CD4⁺/CD62L low cells) and CD4⁺/CD8⁺ (lower panels, gated on CD3⁺ cells) analyses. (B) Intravenous immunoglobulin (IVIg) induced a mild but significant increase in Treg relative population but not in (C) iCOS⁺/Foxp3⁺ or (D) iCOS⁺ populations. IVIg treatment also decreased the (E) CD4⁺/CD8⁺ cell ratio. (B) to (E) Results are presented as mean ± standard error of the mean (10 to 15 animals). Statistical analysis: *P <0.05 versus vehicle-control group, one-way analysis of variance (ANOVA), followed by Dunnett’s multiple comparison test, ^∞ P <0.05 IVIg versus control, two-way ANOVA.