Synovial Cells (SYC)

The intimal cells in synovial membrane are of two types, fibroblasts synovial cells or type B cells and macrophages-like synovial cells. The fibroblast-like synovial cells (Synovial Cells) are derived from mesenchyme, they can manufacture a long-chain sugar polymer called hyaluronan, hence the synovial fibroblasts are rich in endoplasmic reticulum; which makes the synovial fluid "ropy"-like egg-white, together with a molecule called lubricin, which lubricates the joint surfaces. The water of synovial fluid is not secreted as such but is effectively trapped in the joint space by the hyaluronan.The macrophage-like synovial cells are derived from monocytes in blood, they are responsible for the removal of undesirable substances from the synovial fluid . It accounts for approximately 25% of cells lining the synovium.