Impaired membrane resealing and autoimmune myositis in synaptotagmin VII–deficient mice

Members of the synaptotagmin family have been proposed to function as Ca2+ sensors in membrane fusion. Syt VII is a ubiquitously expressed synaptotagmin previously implicated in plasma membrane repair and Trypanosoma cruzi invasion, events which are mediated by the Ca2+-regulated exocytosis of lysosomes. Here, we show that embryonic fibroblasts from Syt VII–deficient mice are less susceptible to trypanosome invasion, and defective in lysosomal exocytosis and resealing after wounding. Examination of mutant mouse tissues revealed extensive fibrosis in the skin and skeletal muscle. Inflammatory myopathy, with muscle fiber invasion by leukocytes and endomysial collagen deposition, was associated with elevated creatine kinase release and progressive muscle weakness. Interestingly, similar to what is observed in human polymyositis/dermatomyositis, the mice developed a strong antinuclear antibody response, characteristic of autoimmune disorders. Thus, defective plasma membrane repair in tissues under mechanical stress may favor the development of inflammatory autoimmune disease

Anatomy of the Pancreas

Book description: This comprehensive three-volume encyclopedia is a comprehensive study of the entire digestive pathway, with nearly 500 focused articles. Each specific anatomical site such as the esophagus, stomach, liver, and pancreas is covered in its own subject area. The biology of gastroenterology is dealt with in areas such as anatomy and development, cell biology, and hormones, while clinical issues are also thoroughly covered in sections such as surgery, cancer, parasitology, and radiology and endoscopy

Exocrine Pancreas (Structure)

Book description: This comprehensive three-volume encyclopedia is a comprehensive study of the entire digestive pathway, with nearly 500 focused articles. Each specific anatomical site such as the esophagus, stomach, liver, and pancreas is covered in its own subject area. The biology of gastroenterology is dealt with in areas such as anatomy and development, cell biology, and hormones, while clinical issues are also thoroughly covered in sections such as surgery, cancer, parasitology, and radiology and endoscopy