Lymphocyte, microglia and B cell populations in the brain.

Flow cytometric analysis of cell populations in brain tissue collected at necropsy. Tissues were not collected from two animals due to tissue degradation. For each animal, samples were collected from three different regions of the brain, the gray matter, white matter and tissue immediately adjacent to the ventricles to include the ependyma. A random tissue section was also collected (Misc) if it appeared on gross examination to be of interest. The specific markers used to distinguish cell populations are indicated below the individual panels. Analyses included the Ki67 marker in B cells to determine if cell populations were proliferating. Animals included in this analysis included 8043 (filled circle), 8234 (open square), 8197 (half filled square) and 8155 (filled square). Individual cell populations included (A) lymphocytes; (B) putative microglia; (C) B cells; (D) Ki67+ B cells. Markers and antibody clones used for these analyses can be found in S3 Table. The solid lines represent the mean for that dose group.