2005 年 14 巻 1 号 p. 37-40
Low reactive-level laser therapy (LLLT) is a safe and easy therapeutic modality and now utilized in the treatment of inflammatory conditions. However, the clinical evidence base for such application remains sparse. This study was designed to examine the effects of LLLT on production of interleukin-8 (IL-8) by human neutrophils. Neutrophils, separated from blood drawn from 10 healthy volunteers, received laser irradiation (150 mW/cm2) for 30 or 60 sec at 60 min prior to or just before the stimulation with opsonized zymosan. These conditions had different effects on production of reactive oxygen species by neutrophils. After the incubation at 37 °C for 3 and 9 hours, the concentration of IL-8 was measured by ELISA. The concentration of IL-8 was higher when neutrophils were incubated longer. However, the levels of IL-8 production by irradiated neutrophils did not differ from those of unirradiated neutrophils even under the conditions whereby both the period of irradiation and the duration from irradiation to stimulation were different. IL-8 production by neutrophils may not play a role in the therapeutic effects of LLLT in inflammatory conditions.
