title: Immunohistological intensity measurements as a tool to assess sarcolemma-associated protein expression.
abstract: OBJECTIVE
  The quantification of protein levels in muscle biopsies is of particular relevance in the diagnostic process of neuromuscular diseases, but is difficult to assess in cases of partial protein deficiency, particularly when information on protein localization is required. The combination of immunohistochemistry and Western blotting is often used in these cases, but is not always possible if the sample is scarce. We therefore sought to develop a method to quantify relative levels of sarcolemma-associated proteins using digitally captured images of immunolabelled sections of skeletal muscle.
  
  
  METHODS
  To validate our relative quantification method, we labelled dystrophin and other sarcolemmal proteins in transverse sections of muscle biopsies taken from Duchenne muscular dystrophy and Becker muscular dystrophy patients, a manifesting carrier of Duchenne muscular dystrophy and normal controls.
  
  
  RESULTS
  Using this method to quantify relative sarcolemmal protein abundance, we were able to accurately distinguish between the different patients on the basis of the relative amount of dystrophin present.
  
  
  CONCLUSIONS
  This comparative method adds value to techniques that are already part of the diagnostic process and can be used with minimal variation of the standardized protocols, without using extra amounts of valuable biopsy samples. Comparative quantification of sarcolemmal proteins on immunostained muscle sections will be of use to establish both the abundance and localization of the protein. Moreover, it can be applied to assess the efficacy of experimental therapies where only partial restoration or upregulation of the protein may occur.
authors.affiliation: The Dubowitz Neuromuscular Centre, Institute of Child Health, University College London, UK.
authors.forename: V
authors.initials: V
authors.lastname: Arechavala-Gomeza
authors.forename: M
authors.initials: M
authors.lastname: Kinali
authors.forename: L
authors.initials: L
authors.lastname: Feng
authors.forename: S C
authors.initials: SC
authors.lastname: Brown
authors.forename: C
authors.initials: C
authors.lastname: Sewry
authors.forename: J E
authors.initials: JE
authors.lastname: Morgan
authors.forename: F
authors.initials: F
authors.lastname: Muntoni
mesh_terms: D016022:Case-Control Studies; D002648:Child; D003937:Diagnosis, Differential; D016189:Dystrophin / Q000378:metabolism; D005260:Female; D006579:Heterozygote; D006801:Humans; D007091:Image Processing, Computer-Assisted; D007150:Immunohistochemistry / Q000379:methods*; D008297:Male; D008565:Membrane Proteins / Q000378:metabolism*; D018482:Muscle, Skeletal / Q000378:metabolism*; D020388:Muscular Dystrophy, Duchenne / Q000175:diagnosis / Q000235:genetics / Q000378:metabolism; D012508:Sarcolemma / Q000378:metabolism; D012600:Scoliosis / Q000378:metabolism; D012984:Software
chemical_list: D016189:Dystrophin; D008565:Membrane Proteins; C109742:SLMAP protein, human