MuHV-4 specific B cells represent a minor part of infected and non-infected cells.

<p>(A) As presented in the FACS plot, infected (CD19⁺ YFP⁺, black bars) and non-infected (CD19⁺ YFP⁻, grey bars) B cells were sorted from C57BL/6 mice 14 dpi. Cells were used to assess the frequency of total (left) and MuHV-4 specific (right) antibody-secreting cells (ASC) by ELISPOT. These data are from 3 independent experiments, in each experiment spleens from 3 to 4 mice where pooled before performing the sorts. Post-sorts purities were systematically >95% for YFP⁺ B cells and >98% for YFP⁻ B cells. (B) To monitor the frequency of GC cells in YFP⁻ and YFP⁺ B cells, spleens from YFP-MuHV-4 infected C57BL/6 mice (n = 9) were isolated at 14 dpi for FACS analysis. All the mice harbored a frequency of infected B cells >0,05%, with at least 500 events in the YFP⁺ gate. A representative FACS plot showing the frequency of CD95⁺ GL-7⁺ cells is shown on top and compiled data obtained from 4 independent experiments is shown below. Bars represent the average percentage.