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Hong et al.                                                                                                                                                                              Auto-reactive B cells in MuSK MG

           was no  difference between immunosuppressed  and   Ethics approval
           non-immunosuppressed patients either. However, the   This article does not contain any studies with human
           plasma B-cell activating factor (BAFF) levels were   participants or animals.
           significantly increased in MuSK MG patients; another
           main  finding  of  this  study  is  that  in  vitro  stimulation   REFERENCES
           of  peripheral  blood  mononuclear  cells  resulted  in
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                                                                 with myasthenia gravis without acetylcholine receptor antibodies. Nat
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           for the survival and differentiation of B cells. A clinical   Xiong WC, Lisak RP, Tzartos SJ, Mei L. Autoantibodies to lipoprotein-
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           It will be interesting to see if the drug is effective for   4.   Pevzner A, Schoser B, Peters K, Cosma NC, Karakatsani A, Schalke B,
           MuSK  MG  which  is  often  refractory  to  conventional   Melms A, Kröger S. Anti-LRP4 autoantibodies in AChR- and MuSK-
           immunosuppressive treatment. Second, B10 cells are    antibody-negative myasthenia gravis. J Neurol 2012;259:427-35.
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           studies of larger number of patients would help    7.   Klooster  R,  Plomp  JJ,  Huijbers  MG,  Niks  EH,  Straasheijm  KR,
           further elucidate the precise immunobiology of this   Detmers FJ, Hermans PW, Sleijpen K, Verrips A, Losen M, Martinez-
           rare autoimmune disease.                              Martinez P, De Baets MH, van der Maarel SM, Verschuuren JJ. Muscle-
                                                                 specific  kinase  myasthenia  gravis  IgG4  autoantibodies  cause  severe
           Financial support and sponsorship                     neuromuscular junction dysfunction in mice. Brain 2012;135:1081-101.
           Nil.                                               8.   Guptill JT, Yi JS, Sanders DB, Guidon AC, Juel VC, Massey JM, Howard
                                                                 JF Jr, Scuderi F, Bartoccioni E, Evoli A, Weinhold KJ. Characterization
           Conflicts of interest                                 of B cells in muscle-specific kinase antibody myasthenia gravis. Neurol
           There are no conflicts of interest.                   Neuroimmunol Neuroinflamm 2015;2:e77.
                                                              9.   Yi JS, Guidon A, Sparks S, Osborne R, Juel VC, Massey JM, Sanders
           Patient consent                                       DB, Weinhold KJ, Guptill JT. Characterization of CD4 and CD8 T cell
           No patient involved.                                  responses in MuSK myasthenia gravis. J Autoimmun 2014;52:130-8.




























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