Macrophage activity modulation via synergistic effect of a porous substrate and low-field laser therapy.

Purpose: The aim of this study was to investigate the effect of substrate - polycaprolactone (PCL)-based porous membrane modified with rosmarinic acid (RA), (PCL-RA) and to determine the optimal values of low field laser irradiation (LLLT) as stimulators of biological response of RAW 264.7 macrophages.

Methods

The porous polymer membrane was obtained by the phase inversion method, the addition of rosmarinic acid was 1%wt. The reference material was pure polymer membrane. RAW 264.7 were deposited on the material and then irradiated with a laser with a wavelength of 808 nm, a power of 100 mW, an irradiation dose of 2 J/cm2/cell well, applied continuously (C), (100/2/C) or pulsed (I), (100/2/I).

Results

Macrophage irradiation resulted in an increase in their adhesion. Modifying the PCL membranes with rosmarinic acid had no effect on cell viability on day 3 of the cell culture. Irradiation of macrophages cultured on PCL-RA material increased their viability. Irradiation of macrophages cultured on PCL-RA material decreased macrophage secretion of NO and protein and the increase in TNF and MCP-1 secretion was only transient on day 3 of culture.

Conclusions

Macrophage irradiation had a positive effect on macrophage attachment. Modification of PCL membranes with rosmarinic acid influenced the biological activity of macrophages. Culture of macrophages on rosmarinic acid-modified PCL membranes and simultaneous irradiation of LLLT cells resulted in anti-inflammatory effects.