Electron microscopy of porcine synovial cell layer

Abstract A fine structural study of the normal synovial cells from 8 pigs revealed 3 cell types as evidence of variation in the presence of cytoplasmic organelles. One was a cell with a well developed, rough endoplasmic reticulum, an occasional Golgi apparatus and mitochondria. The second type contained a poorly developed, rough endoplasmic reticulum, numerous pinocytic vesicles and membrane-bound vesicles. The third type had a relative absence of cytoplasmic organelles. Acid phosphatase staining was associated with membrane vacuoles at the margin of the cell and discrete foci within the cytoplasm. No distinct basement membrane was observed.