H-1 PV preserves or even enhances non-activated and activated CD4+ T cell secretion ability.

<p>CD4+ T cells were inoculated with increasing amounts of purified H-1 PV or mock-treated as described in <a href="http://www.plosone.org/article/info:doi/10.1371/journal.pone.0032197#s4" target="_blank">Materials and Methods</a> section. MOI : multiplicity of infection, expressed as the number of plate-forming unit/cell; p.i : post-infection. <b>A</b>. <i>Early and late activation marker expression is increased at the surface of CD4+ T cells upon H-1 PV infection</i>. In the course of infection, cells were collected, labelled for the expression of early (CD69) and late (CD30) activation markers and analyzed using flow cytometry. Results are expressed as percentages of activated cells within CD4+ T cell population. <b>B</b>. <i>H-1 PV enhances CD4+ T cell ability to secrete Th1 and Th2 type cytokines</i>. In the course of infection, culture supernatants were collected and tested for cytokine detection by enzyme-linked immunosorbent assay (ELISA). Results are expressed in pg/ml as the mean of duplicate wells and after subtraction of the background value. Statistical analysis for 2 independent experiments was performed using a Mann-Whitney test (* p<0,05 relative to Mock condition). <i>Representative data from 2 independent experiments</i>.