Figure 3. Effect of the NIR laser on cultured MCs and keratinocytes.

A–B, The effect of the NIR laser on MCs. A, Release of reactive oxygen species (ROS) by the NIR laser treatment was assessed using a ROS-sensitive fluorescence probe H₂DCFDA in BMMCs in vitro. The differentiated BMMC culture was treated with the NIR laser at a power of 0.5 W/cm² for 1–3 minutes. ROS-activated DCF-fluorescence was measured by flow cytometry. B, Fold increase in DCF⁺ population compared to no laser-treated control was calculated for each experiment. One-way ANOVA followed by the Tukey’s HSD tests. n= 6, 8, 12, 7, 6, 6, 6 for no H₂DCFDA control, no laser control, CW 1064 nm for 1 minute, CW 1064 nm for 3 minutes, no laser control with NAC, CW 1064 nm for 1 minute with NAC, H₂O₂-treated positive control groups, respectively. Results were pooled from 3 independent experiments. C–D, The effect of the NIR laser on primary cultured keratinocytes. C, Release of ROS in primary cultured human dermal keratinocytes in response to the CW NIR laser at a power of 0.5 W/cm² for 1 minute was assessed in vitro as described above. D, Fold increase in DCF⁺ population compared to no laser-treated control was calculated. One-way ANOVA followed by the Tukey’s HSD tests. n= 3 each for no H₂DCFDA control, no laser control, CW 1064 nm for 1 minute, no laser control with NAC, CW 1064 nm for 1 minute with NAC, H₂O₂-treated positive control groups, respectively. Representative data from 2 independent experiments are presented.