The CD31 molecule: a possible neuroprotective agent in acute ischemic stroke?

BACKGROUND: The transmembrane receptor molecule CD31 is known to have immunomodulatory functions, suggesting a possible neuroprotective effect in the context of acute ischemic stroke by restricting an over-activation of secondary immunological processes. This study examines the density of CD31(+) cells in mechanically extracted thrombi of stroke patients with the aim to test whether the occurrence of CD31(+) cells was associated with a beneficial clinical outcome in those patients. METHODS: Thrombi of 122 consecutive patients with large anterior circulation stroke were collected during intracranial mechanical recanalization. Out of these, 86 immunostained specimens of adequate quality could be analysed. The density of CD31(+) cells was quantified and compared with clinical outcome data of the affected patients. RESULTS: The density of CD31(+) cells was positively related to early patient improvement (ΔNIHSS, r = 0.283, p = 0,012) with an even clearer relationship after exclusion of patients who died in the early hospital phase (r = 0.371, p = 0.001). This finding stayed stable also in the multivariate analysis after corrrection for other outcome-influencing factors (p = 0.049). CONCLUSION: This study shows a stable relation between CD31(+) cells and early clinical improvement of patients with acute ischemic stroke. This finding is in line with recent reports showing immunomodulatory and potential neuroprotective effects of CD31, suggesting that CD31 may be a promising neuroprotective agent in stroke patients.