Collagenase-like activity associated to the leukemic WEHI-3B cell line

The leukemic cell line, WEHI-3B presents a latent collagenase-like activity which is activated after trypsin treatment. The enzymatic activity is not released from cells and is specific for the degradation of interstitial collagens. After attachment of WEHI cells to a hemopoietic stroma derived from long-term bone marrow cultures, the organization of the stroma is disrupted. This effect was not observed after the attachment to stroma of normal progenitor cells. These results suggest that the collagenase-like activity in leukemic cells may contribute through collagen degradation, to the disorganization of the marrow stroma. The latter was confirmed by the use of a labeled-collagen containing stroma, which was degraded when cocultured with WEHI cells, but not with normal progenitor cells.