Dissociation between serine proteinases and proline related enzymes in spleen of MRL mouse as a model of systemic lupus erythematodes.

We investigated the changes in the activities of proteases and other hydrolytic enzymes in spleens of MRL mice as a model of systemic lupus erythematodes (SLE). Although there are various abnormalities in the activities of proteases in the spleens of such animals, a multivariate study helped to extract two important components. The first component, representing the activities of serine proteinases, tended to decrease with advancing age in MRL mice but not in control animals. The second component, representing Pro-IP and prolyl endopeptidase, tended to decrease with advancing age in control animals, but not in the MRL mice. The discrepancy between these two components may be related to the immunopathologic disturbances in this model.