The isolation and characterization of a proposed adipocyte precursor cell type from bovine subcutaneous white adipose tissue

Abstract

(1) The isolation and propagation of stromal cells from mature bovine subcutaneous white adipose tissue is described. The cells formed a homogenous population and synthesized collagen Types I and III in a ratio identical to that of bovine lung fibroblasts studied at the same stage of culture development. (2) Unlike lung fibroblasts the adipose tissue stromal cells (fibroblasts) accumulated lipid in the post confluence stage of culture development and lipoprotein lipase activity emerged. The emergence of lipoprotein lipase in these cells was not dependent on insulin in the medium unlike the 3T3-L1 mouse embryo pre-adipocytes studied in parallel. (3) Post-confluence the adipose tissue stromal cells preferentially incorporated more exogenous [14C]acetate into neutral lipids than a preconfluency. This was in distinction to the lung fibroblast cultures in which the ratio of acetate incorporated into neutral and polar lipids remained unchanged throughout. (4) From the data presented and by comparison with similar adipose tissue derived cells from other species it is proposed that mature bovine white adipose tissue contains cells which have the potential to differentiate from a fibroblast towards an adipocyte phenotype.