| Objective: To investigate the role of peripheral blood monocytes/macrophages in the post-ischemic stroke immune and inflammatory responses.Methods: The baseline clinical data and peripheral blood were collected from 81 patients with acute ischemic stroke and 52 healthy controls.Peripheral blood mononuclear cells and plasma were collected on the day of admission and day 14 since stroke-onset from the ischemic stroke group,and the phenotypes of monocytes/macrophages were analyzed by flow cytometry,and plasma cytokine levels were determined using enzyme-linked immunosorbent assay and Luminex assay.Results: There were difference on gender and age between 81 patients with acute ischemic stroke and 52 healthy individuals.Analysis of peripheral blood revealed that the case group had significantly higher white blood cell counts,monocyte counts,neutrophil counts,neutrophil-to-lymphocyte ratio and C-reactive protein compared to the control group(P<0.001),while the lymphocyte counts were lower than controls(P<0.05).At admission with 72 hours,the expressions of the M1 type monocytes/macrophages markers(CD40、CD86 and HLA-DR)and M2-markers(CD163、CD206 and Arg-1)were all higher in peripheral blood of IS patients than those in controls(P<0.05).Particularly,the expression of HLA-DR,a typical marker for M1 type monocytes/macrophages,was obviously upregulated in IS group(P<0.001).When the disease entered into the subacute phase(day 14 since onset),the expression of M1(CD40,CD86,HLA-DR)markers on peripheral blood monocytes/macrophages decreased significantly,whereas the proportion of monocytes/macrophages expressing M2 markers(CD163,CD206,Arg-1)was significantly upregulated(P<0.05)compared with the acute phase.The expression of M1(mainly CD86)and M2(mainly CD206)markers was higher in patients with large artery atherosclerosis and infarct site in the cortex than in patients with small artery occlusion and infarct site in the subcortex(P<0.05).Conclusion:(1)Monocytes/macrophages display dynamic changes of phenotypes during the development of post-ischemic stroke immune and inflammatory responses;(2)In the acute phase of cerebral ischemia,as the neurological functions declined obviously,the peripheral monocytes/macrophages were mainly M1 type;along with the improvement of disease,the monocytes/macrophages gradually transformed to M2 type,accompanied by improved neurological functions;(3)Regulation of the polarized monocytes/macrophages phenotypes might be a hopeful therapeutic target for ischemic stroke in the future. |
