title: [Role of miR-155 in myasthenia gravis and effect of dexamethasone on miR-155].
abstract: OBJECTIVE
  To determine the role of miR-155 in the pathogenesis of generalized myasthenia gravis (GMG) and the effect of dexamethasone (DXM) on miR-155.
  
  
  METHODS
  The expression of miR-155 in B cells from the GMG patients and healthy controls was analyzed by qPCR. The B cells were cultured with DXM and PBS. The B cell proliferation was examined by MTT; CD80 and CD86 frequencies were detected by flow cytometry; and anti-AChRIgG and isotypes anti-AChR-IgG1, 2, 3 in the supernatant were detected by ELISA.
  
  
  RESULTS
  qPCR revealed that the expression of miR-155 in the B cells was much higher than that in the controls, and the miR155 expression decreased after DXM treatment. flow cytometry showed that there was no significant difference in the proliferation and the expressions of CD80 and CD86 in the B cells between the DXM group and the PBS group. The concentration of anti-AChR-IgG1 was obviously lower in the DXM group than in the PBS group, but the concentration of anti-AChRIgG, anti-AChR-IgG2, and anti-AchR-IgG3 was similar.
  
  
  CONCLUSIONS
  high expression of miR-155 may be associated with myasthenia gravis progression. DXM may disturb the antibody class switch of B cells by suppressing the expression of miR-155 and improve the symptom of MG patients.
authors.affiliation: Department of Neurology, Xiangya Hospital, Central South University, Changsha 410008, China.
authors.forename: Xiaoli
authors.initials: X
authors.lastname: Chen
authors.forename: Yuqian
authors.initials: Y
authors.lastname: Chen
authors.forename: Yuzhong
authors.initials: Y
authors.lastname: Wang
authors.forename: Mei
authors.initials: M
authors.lastname: Yan
authors.forename: Junmei
authors.initials: J
authors.lastname: Zhang
authors.forename: Qun
authors.initials: Q
authors.lastname: Liu
authors.forename: Huan
authors.initials: H
authors.lastname: Yang
authors.forename: Jing
authors.initials: J
authors.lastname: Li
mesh_terms: D000328:Adult; D001402:B-Lymphocytes / Q000166:cytology / Q000276:immunology* / Q000378:metabolism; D018122:B7-1 Antigen / Q000378:metabolism; D049109:Cell Proliferation; D002478:Cells, Cultured; D003907:Dexamethasone / Q000627:therapeutic use*; D005260:Female; D006801:Humans; D007074:Immunoglobulin G / Q000276:immunology; D008297:Male; D035683:MicroRNAs / Q000235:genetics* / Q000378:metabolism; D008875:Middle Aged; D009157:Myasthenia Gravis / Q000188:drug therapy* / Q000235:genetics* / Q000276:immunology; D011950:Receptors, Cholinergic / Q000276:immunology; D060225:Tetraspanin 28 / Q000378:metabolism; D055815:Young Adult
chemical_list: D018122:B7-1 Antigen; D007074:Immunoglobulin G; C524942:MIRN155 microRNA, human; D035683:MicroRNAs; D011950:Receptors, Cholinergic; D060225:Tetraspanin 28; D003907:Dexamethasone