Adoptive transfer of immune subsets prior to MCAO does not exacerbate stroke outcome in splenectomized mice

The peripheral immune response contributes to neurologic impairment after stroke and the extent of initial damage is greater in males than females. We have previously shown that spleen cells directly contribute to ischemic damage in males, as splenectomy prior to experimental stroke eliminates the sex differences in infarct volume. This study aims to determine which specific subset of immune cells exert pathogenic effects when injected 24 hours before MCAO induction into splenectomized male and female WT mice. The results demonstrate that CD4/CD8/CD11b treated mice had no significant effect on infarct volumes vs. vehicle-treated control mice after MCAO. However, there were significant alterations to the resident peripheral immune composition. These results suggest that there are regulatory factors resulting from splenectomy or other possible influences that inhibit peripheral immune cell contribution to neuroinflammation and thus contributing to differential effects of the spleen on stroke outcome in males and female mice.