Macrophage participate or play a leading role in all stages of atherosclerosis. Therefore, identifying and regulating genes that code for macrophage functions in atherosclerotic lesions has the potential of preventing many aspects of this vascular disease. The present application proposes to adapt anti-DNA antibodies for the purpose of repressing genes that promote the atherosclerotic process and depend on the AP-1 transcription factor for expression. Preliminary data suggest that the AP-1 dependent transcription of the interstitial collagenase (MMP-1) gene is effectively repressed by intracellular fusion proteins consisting of a single-chain anti-DNA Fv fragment (scFv) and leucine zipper (Lz) domains derived from c-Jun or c-Fos. The goal of the present proposal is to extend these studies to other AP-l activated genes expressed by macrophage that are implicated in aspects of atherosclerosis. Expression vectors for anti-DNA scFv-LZ fusion proteins will be transfected into the human U937 and THP-1 monocytic cell lines as well as into purrried monocytes from peripheral blood. The expression of the genes for the following proteins will be investigated to establish the extent to which they are susceptible to AP-1 inhibition: 1. The beta2 integrin family adhesion molecule CD11c (p150,95) that is predominantly expressed on monocytes and macrophage and contributes to their adhesion to activated endothelial cells; 2. The matrix metalloprotease MMP-1 that is expressed in a cell tppe selective manner by monocytic cells and contributes to extracellular matrix (ECM) degradation and fibrous plaque rupture; 3. The scavenger receptor that becomes expressed as monocytes differentiate into foam cells and that mediates oxidized low density lipoprotein absorption; 4. Tissue factor, an enzyme expressed on the surface of foam cells in atherosclerotic lesions that acts as a cofactor for Factor VIIa and thus participates in the first reaction of the extiiinsic pathway of coagulation. There is preliminary evidence that each of these genes requires AP-1 for trnscription and therefore should be repressed by AP-1 inhibition. It is hoped that the proposed experiments will lay the foundation for the future testing of these treatments in animal models of atherosclerosis.
