Cell-populated floating collagen lattices: an in vitro model of parenchymal contraction

The pathology of progressive renal disease is characterized by glomerular and interstitial inflammation, glomerulosclerosis, and tubulointerstitial fibrosis. This is a consequence of excessive matrix synthesis, reduced matrix degradation, and contraction (reorganization) of extracellular matrix. Fibroblasts, and to a lesser degree, other mesenchymal cells, are known to contribute to renal scar formation through local proliferation, synthesis, and reorganization of matrix proteins. Although much work has focused on the balance between collagen synthesis and degradation, the mechanisms of parenchymal collapse and contraction are becoming increasingly important. Like their counterparts in the skin, the contractile properties of renal fibroblasts are now well recognized. This chapter details an in vitro method for studying the contraction of collagens by homogeneous populations of cultured cells. The method can be altered so that reagents influencing this process may also be studied.