ABSTRACT
Mononuclear cells often accumulate at the sites of tumor growth or metastasis, and these tissue-infiltrating cells are considered to be important in the control of tumor spread. Development of effective antitumor local immune responses depends on the ability of lymphocytes to extravasate and migrate into nonlymphoid solid tissues. This chapter focuses on antimetastatic therapeutic potential of lymphocytes as antitumor effector cells. Considerable progress has been made recently in studies of the mechanisms involved in lymphocyte movement through tissues, including interactions with extracellular matrix components, vascular elements and other tissue cells. Substantial evidence exists indicating that cellular proteases contribute to degradation of subendothelial extracellular matrices. Proteolytic fragments of extracellular matrix molecules such as laminin and fibronectin are known to be chemotactic and/or haptotactic for various cell types. The discovery and biochemical purification of non-granular proteolytic enzymes of natural killer (NK) cells identify candidates for potential roles in NK cell functions including degradation of host extracellular matrices and NK cell migration.
