Figure 5.

Activation of naïve CD4⁺ T-cells is impaired during late Plasmodium blood stage infection. DO11.10 naïve CD4⁺ T-cells isolated from the spleens of transgenic mice were labeled with CFSE and transferred into uninfected or P. yoelii-infected mice (10 days after infection). Mice were immunized or not with OVA 24 h after transfer of T-cells. Three days after immunization, transferred CD4⁺ T-cells from spleens of recipient mice were analysed by FACs for (A) total number in the spleen, (B) proliferation (determined as decrease in CFSE fluorescence), (C) up-regulation of CD11a surface expression, (D) down-regulation of CD62L surface expression, and (E) increase in intracellular IL-2 production. Results are expressed as the difference between values obtained with non-immunized versus OVA-immunized mice. Results are expressed as mean ± SD of triplicate samples. FACs analysis with the gates for transferred cells are shown in Additional file 4.