A role for matrix metalloproteinases in the pathology and attenuation of Theileria annulata infections.

Upon infection with Theileria annulata, bovine leukocytes are induced to express eight novel metalloproteinase activities. In this article, Rachel Adamson and Roger Hall suggest that these enzymes are virulence factors and their presence may explain some of the features of the pathology of the disease. Specifically, they discuss the possibility that the metastatic properties of infected cells, the 'cigarette burn' ulcers and the cachexia characteristic of tropical theileriosis are associated with metalloproteinase expression. Furthermore, they propose that loss of metalloproteinase activity during the generation of a vaccine line could explain the attenuated phenotype.