<b>Conclusions</b>: Our findings provide evidence that exosomes are efficient carriers of dysferlin and can be employed for the treatment and non-invasive diagnosis of dysferlinopathy.
Dysferlinopathy is characterized by absence or marked reduction of dysferlin protein with 43% of reported pathogenic variants being missense variants that span the length of the dysferlin protein.
Dysferlin is likely required for maintaining the structural integrity of the muscle fiber plasma membrane, and plasma membrane injury is an early event in the pathogenesis of dysferlinopathy.
Dysferlin is known to play an essential role in skeletal muscle fibre repair, but the process underlying the pathogenetic mechanism of dysferlinopathy is not completely understood.
A newly developed kit for multiplex ligation-dependent probe amplification analysis of the dysferlin gene was used for a total of 12 samples from patients with suspected diagnosis of primary dysferlinopathy.
Additional findings of histopathology, specific stain for sarcolemmal membrane protein, Western blot analysis and clinical presentation clinched the diagnosis further of dysferlinopathy (LGMD2B) in both our patients.
Altered immunolocalization of dysferlin was observed in not only primary dysferlinopathy, but also in the several diseased muscles with normal protein contents.
Although muscle inflammation is widely recognized in dysferlinopathy and dysferlin is expressed in immune cells, the contribution of the immune system to the pathology of dysferlinopathy remains to be fully explored.
Case report of an adolescent girl with limb-girdle muscular dystrophy type 2B - the usefulness of muscle protein immunostaining in the diagnosis of dysferlinopathies.