The immunologic profile of adoptively transferred lymphocytes influences stroke outcome of recipients

• LPS skews the MBP immune response to a Th1(+) response in donor animals.
• Cerebral ischemia itself is associated with a Th17(+) response to MBP.
• MBP specific Th1(+) and Th17(+) cells lead to worse stroke outcome.

Animals that have myelin basic protein (MBP) specific lymphocytes with a Th1(+) phenotype have worse stroke outcome than those that do not. Whether these MBP specific cells contribute to worsened outcome or are merely a consequence of worse outcome is unclear. In these experiments, lymphocytes were obtained from donor animals one month after stroke and transferred to naïve recipient animals at the time of cerebral ischemia. The MBP specific phenotype of donor cells was determined prior to transfer. Animals that received either MBP specific Th1(+) or Th17(+) cells experienced worse neurological outcome, and the degree of impairment correlated with the robustness of MBP specific Th1(+) and Th17(+) responses. These data demonstrate that the immunologic phenotype of antigen specific lymphocytes influences stroke outcome.