"Epithelial Transformation" of Human Synovial Connective Tissue Cells: Cytologic and Biochemical Consequences

Abstract
Primary cultures of Fibroblast-like cells from rheumatoid synovial tissue changed in vitro to a cell population exhibiting epithelial morphology, heteroploidy, altered growth characteristics and decreased capacity to form hyaluronic acid. The amount of protein and DNA per cell approximately doubled, while no change in the quantity of RNA was noted. The characteristics of the "transformed" cell are also compared with the J-111 malignant monocyte and a collection of normal synovial derivatives.