Abstract
Purpose :
Corneal fibroblasts (CF) have a high phagocytic activity. The phagocytic function of CF plays an important role in corneal stromal wound healing. In this study we examined the effect of plasminogen on phagocytosis by CF.
Methods :
The ability of plasminogen to bind CF was measured with a real-time cell-molecular interaction assay system, IAsys resonant mirror biosensor. To investigate the phagocytic activity, plastic beads labeled with FITC were used in this study. CF were incubated in media containing plasminogen and plastic beads for 2 hours or 24 hours. The effects of plasminogen on phagocytic activity of CF was measured by flow cytometry. To clarify the mechanism of phagocytic activity by plasminogen, we used 6-Aminohexanoic Acid (EACA) which blocks plasminogen binding to receptor on cell surface.
Results :
The binding response of plasminogen to CF was increased in a time-dependent and cell number dependent fashions. For flow cytometry analysis, plasminogen did not promote phagocytic activity at 2 hours after incubation(2.5±1.9%vs. 4.1±1.5%, p<0.01). However, at 24 hours after incubation, plasminogen significantly promoted phagocytic activity(1.9±1.4%vs. 11.7±3.8%, p<0.01). EACA completely inhibited the phagocytic activity stimulated by plasminogen(4.0±0.6%).The binding response of plasminogen to CF was increased in a time-dependent and cell number dependent fashions. For flow cytometry analysis, plasminogen did not promote phagocytic activity at 2 hours after incubation(2.5±1.9%vs. 4.1±1.5%, p<0.01). However, at 24 hours after incubation, plasminogen significantly promoted phagocytic activity(1.9±1.4%vs. 11.7±3.8%, p<0.01). EACA completely inhibited the phagocytic activity stimulated by plasminogen(4.0±0.6%).
Conclusions :
These data demonstrate that plasminogen promotes phagocytic activity of CF. The phagocytic activity by plasminogen depended on the duration of the incubation period. Plasminogen binding to CF is critical to exert its phagocytic activity.
This is an abstract that was submitted for the 2018 ARVO Annual Meeting, held in Honolulu, Hawaii, April 29 - May 3, 2018.