Observations on the Formation of Connective Tissue Fibers.

The formation of fibrils from collagen solutions 1. The effect of experimental conditions: kinetic and electron-microscope studies

“…Opacity measurements (Shulman & Ferry, 1950;Edsall & Lever, 1951) and electron microscopy (Hawn & Porter, 1947;Porter & Hawn, 1949) have been used to study the conversion of fibrinogen into fibrin clots, a system somewhat similar to the precipitation of collagen (Vanamee & Porter, 1951;Schmitt et al 1955a;Schmitt, 1957). As in the collagen system, coarseness of the precipitate or clot (wide fibrils and high degree of lateral aggregation of fibrils) is associated with high opacity, and vice versa, and there is no simple correlation ofthese properties with rate of precipitation.…”

Occupy tissue

“…When cultured at high density, fibroblasts “bioengineer” their own extracellular matrix 46 . This cell-derived matrix (CDM) is composed of fibronectin, 47 collagen types I and II, 48 hyaluronic acid 49 and heparin sulfate proteoglycans 49 , 50 .…”

The Physiology of the Connective Tissue (Loose Areolar)

“…Thus, thrombin in some way activates the fibrinogen particles to adhere face to face and polarizes them so that at cer tain points they attach edge to edge. It has been suggested that collagen is formed by an enzyme present in the ground substance from a soluble polypeptide secreted by the fibroblast (147). By electron microscopy of tissue cultures of fibroblasts, it has been demonstrated that a precollagen consisting of nodular filaments and some larger, finely striated fibrils is present and is believed to represent a stage in extracellular development of collagen (147).…”

“…The formation of fibrin, a fibrous protein, has been carefully studied, and it has been suggested that collagen may follow a similar developmental pattern (147). Fibrin (from purified bqvine fibrinogen and thrombin) has a characteristic electron microscopic structure with an average periodicity of 245 A (83).…”