Diagnostic value of neuronal nitric oxide synthase antibody for clinically suspected Becker muscular dystrophy
LI Xi-Hua, ZHAO Lei, WU Yan, WU Jie, HE Da-Ke, LIU Xiao-Qing
Department of Neuromuscular Disease, Shanghai Institute for Pediatric Research, Xinhua Hospital Affiliated to Shanghai Jiao Tong University School of Medicine, Shanghai 200092, China. Email: xqliu@sh163.net
Abstract：OBJECTIVE: Immunohistochemistry using antibodies to dystrophin is the pathological basis for the differential diagnosis of Duchenne and Becker muscular dystrophy (DMD and BMD). In rare cases, however, labelling dystrophin on sarcolemma is equivocal and similar to that observed in controls. This makes the diagnosis of BMD difficult. This study aimed to explore the diagnostic value of neuronal nitric oxide synthase (nNOS) antibody for clinically suspected BMD. METHODS: Immunohistochemical staining was performed on muscle specimens of 5 cases of BMD with positive expression of Dys-C (3 cases had a confirmed diagnosis of BMD, 2 cases were clinically suspected as BMD) by using dystrophin and nNOS antibodies. Normal muscle specimens from the children with fracture were used as controls. RESULTS: Compared with the controls, the expression of Dys-R, Dys-C and Dys-N was markedly reduced and nNOS was not expressed on sarcolemma in the three cases of definitely diagnosed BMD. The two cases of clinically suspected as BMD had a complete absence of sarcolemmal nNOS, even if had a similar expression of dystrophin on sarcolemma to the controls. CONCLUSIONS: nNOS antibody staining can be used for a definite diagnosis in children with clinically suspected BMD who have the almost normal expression of dystrophin.
LI Xi-Hua,ZHAO Lei,WU Yan et al. Diagnostic value of neuronal nitric oxide synthase antibody for clinically suspected Becker muscular dystrophy[J]. CJCP, 2011, 13(4): 288-291.
［1］Dubowitz V, Sewry CA. Muscle biopsy: a practical approach［M］. 3rd ed. Philadelphia: Elsevier, 2006: 157-180.
［2］Deburgrave N, Daoud F, Liense S, Barbot JC, Récan D, Peccate C, et al. Protein-and mRNA-based phenotype-genotype correlations in DMD/BMD with point mutations and molecular basis for BMD with nonsense and frameshift mutations in the DMD gene［J］. Hum Mutat, 2007, 28(2): 183-195.
［3］Gualandi F, Neri M, Bovolenta M, Martoni E, Rimessi P, Fini S, et al. Transcriptional behavior of DMD gene duplications in DMD/BMD males［J］. Hum Mutat, 2009, 30(2): E310-E319.
［4］Torelli S, Brown SC, Jimenez-Mallebrera C, Feng L, Muntoni F, Sewry CA. Absence of neuronal nitric oxide synthase (nNOS) as a pathological marker for the diagnosis of Becker muscular dystrophy with rod domain deletions［J］. Neuropathol Appl Neurobiol, 2004, 30(5): 540-545.
［5］Arechavala Gomeza V, Kinali M, Feng L, Brown SC, Sewry C, Morgan JE, et al. Immunohistological intensity measurements as a tool to assess sarcolemma-associated protein expression［J］. Neuropathol Appl Neurobiol, 2010, 36(4): 265-274.
［7］Lai Y, Thomas GD, Yue Y, Yang HT, Li D, Long C, et al. Dystrophins carrying spectrin-like repeats 16 and 17 anchor nNOS to the sarcolemma and enhance exercise performance in a mouse model of muscular dystrophy［J］. J Clin Invest, 2009, 119(3):624-635.
［8］Ségalat L, Grisoni K, Archer J, Vargas C, Bertrand A, Anderson JE. CAPON expression in skeletal muscle is regulated by position, repair, NOS activity, and dystrophy［J］. Exp Cell Res, 2005, 302(2): 170-179.
