Quantification of lectin fluorescence in GNE myopathy muscle biopsies

Muscle Nerve. 2018 Aug;58(2):286-292. doi: 10.1002/mus.26135. Epub 2018 Apr 23.


Introduction: GNE myopathy is an adult-onset muscle disorder characterized by impaired sialylation of (muscle) glycans, detectable by lectin histochemistry. We describe a standardized method to quantify (lectin-) fluorescence in muscle sections, applicable for diagnosis and response to therapy for GNE myopathy.

Methods: Muscle sections were fluorescently labeled with the sialic acid-binding Sambucus nigra agglutinin (SNA) lectin and antibodies to sarcolemma residence protein caveolin-3 (CAV-3). Entire tissue sections were imaged in tiles and fluorescence was quantified.

Results: SNA fluorescence co-localizing with CAV-3 was ∼50% decreased in GNE myopathy biopsies compared with muscle-matched controls, confirming previous qualitative results.

Discussion: This quantitative fluorescence method can accurately determine sialylation status of GNE myopathy muscle biopsies. This method is adaptable for expression of other membrane-associated muscle proteins, and may be of benefit for disorders in which therapeutic changes in expression are subtle and difficult to assess by other methods. Muscle Nerve 58: 286-292, 2018.

Keywords: N-acetylmannosamine (ManNAc); SNA lectin; caveolin-3; sarcolemma; sialylation.

Publication types

  • Research Support, Non-U.S. Gov't
  • Research Support, N.I.H., Intramural

MeSH terms

  • Adult
  • Caveolin 3 / genetics
  • Distal Myopathies / genetics
  • Distal Myopathies / pathology*
  • Female
  • Fluorescent Dyes
  • Humans
  • Image Processing, Computer-Assisted
  • Lectins*
  • Male
  • Microscopy, Confocal
  • Middle Aged
  • Muscle, Skeletal / pathology*
  • Plant Lectins
  • Ribosome Inactivating Proteins
  • Sarcolemma / pathology
  • Sarcolemma / ultrastructure


  • CAV3 protein, human
  • Caveolin 3
  • Fluorescent Dyes
  • Lectins
  • Plant Lectins
  • Sambucus nigra lectins
  • Ribosome Inactivating Proteins

Supplementary concepts

  • Distal myopathy, Nonaka type