Formation Of Concentration Gradients Of Monocyte Chemoattractant Protein-1 in a Collagen Matrix

Abstract

This research project determined the formation of the static and soluble concentration gradients of monocyte chemoattractant protein-1 (MCP-1) in a collagen matrix using a 3D in vitro vascular tissue model. Stability of MCP-1 and the binding reaction between MCP-1 and collagen were examined and used to develop a mathematical model to estimate the concentration of MCP-1 within the collagen matrix. Effect of storage conditions on the stability of MCP-1 and the effect of a static gradient of MCP-1 on monocyte migration were also investigated in this project. Findings and Conclusions: Recombinant human MCP-1, within a medium containing 10% fetal bovine serum, is stable at standard cell culture conditions (37?C in humidified atmosphere of 5% CO? and 95% air) for seven days. However, storage conditions and duration, as well as the concentration of MCP-1, can affect the stability of MCP-1 when it is stored at working concentrations. Also, it was found that binding reaction between MCP-1 and collagen does exist and is irreversible. Based on these findings, a mathematical model to describe the transport of MCP-1 through the collagen matrix was developed. Results from the mathematical model showed that both static and soluble concentration gradients of MCP-1 are formed in the matrix. The static gradient of MCP-1 was proven to have haptostatic effect on monocyte migration. When the pattern of the static gradient of MCP-1 was taken in to account, this latter finding suggests that the static gradient of MCP-1 may be responsible for attracting high density of monocyte just below the endothelium, as observed in the site of atherosclerosis lesions.