Dear Editor:Autoantibodies against aquaporin‐4 (AQP4) in seropositive neuromyelitis optica spectrum disorders (called here NMO) initiate pathology in the central nervous system by binding to AQP4 on astrocytes. It has been puzzling why skeletal muscle, which also expresses AQP4, is rarely affected in NMO, despite easy access of circulating NMO autoantibody (AQP4‐IgG) to AQP4 on skeletal muscle.Rosito et al. report evidence that differences in the supramolecular organization of AQP4 in skeletal muscle versus brain astrocytes are responsible for the sparing of skeletal muscle in NMO, arguing that the size of AQP4 supramolecular clusters (called orthogonal arrays of particles, OAPs) is smaller in skeletal muscle than in astrocytes resulting in reduced AQP4‐IgG binding. This mechanism is motivated by the observation that some AQP4‐IgG autoantibodies bind better to AQP4 OAPs than to separated AQP4 tetramers and that AQP4 OAPs are required for C1q binding and complement activation . Although the study of Rosito et al. is a novel and earnest attempt to solve the puzzle of skeletal muscle sparing in NMO, in our opinion their explanation lacks theoretical plausibility and contradicts available data.The authors’ assertion that arrays are smaller in muscle than in brain is based on biochemical analysis and super‐resolution (STED) microscopy. Non‐denaturating
Journal of Cellular and Molecular Medicine – Wiley
Published: Jan 1, 2018
It’s your single place to instantly
discover and read the research
that matters to you.
Enjoy affordable access to
over 12 million articles from more than
10,000 peer-reviewed journals.
All for just $49/month
It’s easy to organize your research with our built-in tools.
All the latest content is available, no embargo periods.
“Whoa! It’s like Spotify but for academic articles.”@Phil_Robichaud