Figure 3

Regulatory activity of 3a-G1 upon CD4⁺ T cell proliferation is direct and T cell restricted. a) CFSE dilution of CD4⁺ T cells within IL-2 treated CFSE labelled PBMCs or depleted of monocytes (Right), CFSE dilution of CFSE labelled purified CD4⁺ T cells ± 3a-G1 ± autologous monocytes (Ratio 5:1). b) Regulatory activity of dendrimers is not mediated by autologous monocytes as 3a-G1 also inhibits CFSE dilution of purified CD4⁺ T cells stimulated with anti-CD3/CD28 coated beads. c) Regulatory activity of 3a-G1 is restricted to T cells as under the same conditions IL-2 stimulated proliferation of autologous NK cells is not affected. Cell cycle analysis shows that the decrease of proliferation of 3a-G1 treated CD4⁺ T cells correlates with a reduction of mitotic events.