Research Article Circulating Th17, Th22, and Th1 Cells Are Elevated in the Guillain-Barré Syndrome and Downregulated by IVIg Treatments

which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly cited. The Guillain-Barre ́ syndrome (GBS) is considered a T helper 1 (Th1) cells-mediated acute inflammatory peripheral neuropathy. However, some changes in GBS could not be explained completely by Th1 cells pathogenic role. Recently, Th17 cells have been identified and canmediate tissue inflammation and autoimmune response.Therefore, a study on the role ofTh17 andTh22 cells and their cytokines in GBS is necessary for exploring the pathogenesis of GBS. Here, we detected the frequency of Th1, Th17, andTh22 cells by using 4-color flow cytometry and we detected the plasma levels of IL-17 and IL-22 by ELISA in GBS patients, relapsing-remitting multiple sclerosis patients at the acute phase of relapse, viral encephalitis or meningitis patients and healthy controls. Our data showed that the frequency of circulatingTh1,Th17, andTh22 cells was significantly increased in GBS patients.The plasma levels of IL-17 and IL-22 in GBS and relapsing-remittingmultiple sclerosis at the acute phase of relapse were alsomarkedly elevated. Enhanced circulatingTh22 cells were correlated with GBS severity. Intravenous immunoglobulin therapy downregulatedTh17, an