Photobiomodulation with single and combination laser wavelengths on bone marrow mesenchymal stem cells: proliferation and differentiation to bone or cartilage

Lasers Med Sci. 2019 Feb;34(1):115-126. doi: 10.1007/s10103-018-2620-8. Epub 2018 Sep 27.


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). MSCs were derived from rabbit iliac bone marrow. One control and eight laser irradiated groups were designated as Infrared (IR, 810 nm), Red (R, 660 nm), Green (G, 532 nm), Blue (B, 485 nm), IR-R, IR-B, R-G, and 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. 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. ALP was decreased by combinations of IR with B and with R, and also by G alone. R and B-G groups showed stimulated COL 1 expression; however, COL 1 was suppressed in IR-B, IR-R, and G groups. IR significantly increased osteocalcin expression, but in B, B-G, and G groups it was reduced. Cartilage differentiation was stimulated by IR and IR-B laser irradiation. The effects of single or combined laser irradiation were not clear-cut on osseous differentiation. Stimulatory effects on osteogenesis were seen for R and IR lasers, while G laser had inhibitory effects.

Keywords: Cartilage; Comparison of wavelengths; Low level light therapy; Mesenchymal stem cells, bone; Photobiomodulation.

MeSH terms

  • Alkaline Phosphatase / genetics
  • Alkaline Phosphatase / metabolism
  • Animals
  • Bone and Bones / cytology*
  • Cartilage / cytology*
  • Cell Differentiation / radiation effects*
  • Cell Lineage / radiation effects
  • Cell Proliferation / radiation effects
  • Cell Shape / radiation effects
  • Cells, Cultured
  • Chondrogenesis / genetics
  • Chondrogenesis / radiation effects
  • Collagen Type I / genetics
  • Collagen Type I / metabolism
  • Collagen Type II / genetics
  • Collagen Type II / metabolism
  • Gene Expression Regulation / radiation effects
  • Lasers*
  • Low-Level Light Therapy*
  • Mesenchymal Stem Cells / cytology*
  • Mesenchymal Stem Cells / radiation effects*
  • Osteogenesis / genetics
  • Osteogenesis / radiation effects
  • Rabbits


  • Collagen Type I
  • Collagen Type II
  • Alkaline Phosphatase