Long-term persistence of CD19+ B cells within the CNS following MCMV brain infection. Single-cell suspensions of brain tissue obtained from MCMV-infected mice were banded on a 70 % Percoll cushion. Brain leukocytes were collected and labeled with PE-Cy5-conjugated Abs specific for CD45, AF700-labeled anti-CD11b, PE-Cy7 anti-CD3, and Cy7-APC anti-CD19 and analyzed using flow cytometry. a Representative histograms show the percentage of CD45+CD19+ cells within the brain-infiltrating CD45hiCD11bloCD3− population obtained from animals at 7, 14, 30, and 60 days post infection b Anti-CD19 staining was used to determine the total number of B cells within the infiltrating CD45hi CD3− population. Pooled data are presented as mean (±SEM) absolute number of infiltrating cells from three independent experiments (n = 6–7 animals/time point). c Immunohistochemical staining demonstrating persistence of CD19+ B cells (brown), as well as CD3+ T cells (blue) within infected brains at 15 and 60 d.p.i.