In contrast, the flow cytometry analysis of brain-infiltrating CD4+ T lymphocytes (t(9) = 0.6418, P = 0.5370), B cell (t(9) = 1.332, P = 0.2157) and neutrophil (t(9) = 1.394, P = 0.1969) did not reveal a significant difference between perioperative stroke mice and stroke-only mice, respectively (Additional file 1: Fig. S3A–F). Here, CD4 is linked to stroke disorder.