Biomedical Engineering Centre, Institute of Optoelectronics, Military University of Technology, Warsaw, Poland.
Optoelectronic Technologies Division, Institute of Optoelectronics, Military University of Technology, Warsaw, Poland.
Int J Radiat Biol. 2021;97(4):553-563. doi: 10.1080/09553002.2021.1876947. Epub 2021 Feb 2.
For effective clinical application of human bone marrow mesenchymal stem cells (hBM-MSCs), the enhancement of their proliferation in vitro together with maintaining the expression of their crucial surface antigens and differentiation potential is necessary. The present study aimed to investigate the effect of light-emitting diode (LED) irradiation on hBM-MSCs proliferation after two, five, or nine days post-irradiation.
The hBM-MSCs were exposed to the LED light at 630 nm, 4 J/cm, and power densities of 7, 17, or 30 mW/cm. To assess the cell proliferation rate in the sham-irradiated and irradiated samples the cells metabolic activity and DNA content were determined. The number of apoptotic and necrotic cells in the samples was also evaluated. The expression of the crucial surface antigens of the hBM-MSCs up to nine days after irradiation at 4 J/cm and 17 mW/cm was monitored with flow cytometry. Additionally, the potential of hBM-MSCs for induced differentiation was measured.
When the metabolic activity was assayed, the significant increase in the cell proliferation rate by 31 and 50% after the irradiation with 4 J/cm and 17 mW/cm, respectively, was observed at day five and nine when compared to the sham-irradiated cells ( < .05). Similarly, DNA content within the irradiated hBM-MSCs increased by 31 and 41% at day five and nine after the irradiation with 4 J/cm and 17 mW/cm in comparison to the sham-irradiated cells. LED irradiation did not change the expression of the crucial surface antigens of the hBM-MSCs up to nine days after irradiation at 4 J/cm and 17 mW/cm. At the same experimental conditions, the hBM-MSCs maintain in vitro their capability for multipotential differentiation into osteoblasts, adipocytes, and chondrocytes.
Therefore, LED irradiation at a wavelength of 630 nm, energy density 4 J/cm, and power density 17 mW/cm can effectively increase the number of viable hBM-MSCs in vitro.
为了使人类骨髓间充质干细胞（hBM-MSCs）在临床上得到有效应用，有必要增强其在体外的增殖能力，同时保持其关键表面抗原的表达和分化潜能。本研究旨在探讨 LED 照射对 hBM-MSCs 增殖的影响，照射后分别在第 2、5、9 天进行检测。
hBM-MSCs 暴露于 630nm 的 LED 光下，能量密度为 4J/cm，功率密度分别为 7、17 或 30mW/cm。为了评估 sham 照射和照射样品中细胞的增殖率，测定了细胞的代谢活性和 DNA 含量。还评估了样品中凋亡和坏死细胞的数量。用流式细胞术监测照射后 4J/cm 和 17mW/cm 时 hBM-MSCs 关键表面抗原的表达情况，直至第 9 天。此外，还测量了 hBM-MSCs 的诱导分化潜能。
当检测代谢活性时，与 sham 照射组相比，照射后第 5 天和第 9 天，分别用 4J/cm 和 17mW/cm 照射的细胞增殖率显著增加 31%和 50%（ < .05）。同样，用 4J/cm 和 17mW/cm 照射的 hBM-MSCs 的 DNA 含量在照射后第 5 天和第 9 天分别增加了 31%和 41%，与 sham 照射组相比。在照射后 4J/cm 和 17mW/cm 条件下，LED 照射直至第 9 天并未改变 hBM-MSCs 的关键表面抗原表达。在相同的实验条件下，hBM-MSCs 保持体外向成骨细胞、脂肪细胞和软骨细胞的多能分化能力。
因此，波长为 630nm、能量密度为 4J/cm、功率密度为 17mW/cm 的 LED 照射可有效增加体外 hBM-MSCs 的存活数量。
