No abstract

Background: Tissue engineering aims to take advantage of the ability of undifferentiated stem cells to differentiate into multiple cell types to repair damaged tissue. Photobiomodulation uses either lasers or light-emitting diodes to promote stem cell proliferation and differentiation. The present study aimed to investigate single and dual combinations of laser wavelengths on mesenchymal stem cells (MSCs). Materials and Methods: MSCs were derived from rabbit iliac bone marrow. One control and 8 laser irradiated groups were designated as: Infra-red (IR, 810nm), Red (R, 660 nm), Green (G, 532 nm), Blue (B, 485 nm), IR-R, IR-B, R-G, B-G. Irradiation was repeated daily for 21 days and cell proliferation, osseous or cartilaginous differentiation was then measured. RT-PCR biomarkers were SOX9, aggrecan, COL 2 and COL 10 expression for cartilage and ALP, COL 1 and osteocalcin expression for bone. Results: Cellular proliferation was increased in all irradiated groups except G. All cartilage markers were significantly increased by IR and IR-B except COL 10 which was suppressed by IR-B combination. ALP expression was highest in R and IR groups during osseous differentiation.