High levels of IL-10 secreting cells are present in blood in cerebrovascular diseases

Ischemic stroke is associated with altered systemic immune responses both e arly after the onset and in the recovery phase. Interleukin (IL)-10, a Th2 related cytokine, has multiple effects on different cell types, including T and B lymphocytes, monocytes, neutrophils and mast cells. IL-4 is another Th2 cytokine that inhibits the synthesis of pro-inflammatory cytokines by T h1 clones. We used enzyme-linked immunospot assays to detect and enumerate blood mononuclear cells (MNC) secreting IL-10 and IL-4 spontaneously as wel l as after stimulation with myelin basic protein (MBP), considered to be an autoantigen of possible pathogenic importance in, for example, multiple sc lerosis, to evaluate the involvement of anti-inflammatory cytokines in isch emic stroke. All patients with ischemic stroke and cerebral hemorrhage had strongly elevated numbers of IL-10 secreting blood MNC compared with health y individuals. Numbers of MBP-reactive IL-10 secreting blood MNC were also elevated in a proportion of the patients with stroke and hemorrhage. Levels of IL-4 secreting blood MNC did not differ in ischemic stroke versus healt hy individuals. The anti-inflammatory IL-10 could play a pivotal role in is chemic stroke as well as cerebral hemorrhage. Eur J Neurol 6:437-442 (C) 19 99 Lippincott Williams & Wilkins.