Effects of 810-nm Laser on Murine Bone-Marrow-Derived Dendritic Cells

Abstract

Objective: The purpose of this study was to Investigate the effect of 810-nm low level laser therapy (LLLT) on dendritic cells (DC) in vitro. Background data: LLLT can enhance wound healing and increase cell proliferation and survival, and is used to treat inflammatory conditions. However there are reports that LLLT can stimulate leukocytes and could therefore be pro-inflammatory. Recently, DC have been found to play an important role in inflammation and immune response. Methods: Murine bone-marrow-derived DC were isolated, stimulated with lipopolysaccharide (LPS) or CpG oligodeoxynucleotide and treated with 810-nm laser, using fluences of 0.3, 3, and 30 J/cm 2 delivered at irradiances of 1, 10, and 100 mW/cm 2 respectively. Confocal microscopy, flow cytometry for DC markers, viability using propidium iodide, enzyme-linked immunosorbent assays (ELISA) for secreted interleukin-12 (IL-12), and bioluminescence measurements in cells transduced with a reporter for toll-like receptor (TLR)-9/nuclear factor kappa B (NF-kB) activation, were performed. Results: LLLT changed the morphology of LPS-stimulated DC, increased their viability, and altered the balance of DC activation markers (major histocompatibility complex [MHC] class 2 up and CD86 down). LLLT reduced IL-12 secretion from DC stimulated by either LPS or CpG. LLLT reduced NF-kB activation in reporter cells stimulated with CpG. There was no obvious light dose response observed. Conclusions: Taken together, these data suggest that 810-nm LLLT has an anti-inflammatory effect on activated DC, possibly mediated by cyclic adenosine monophosphate (cAMP) and reduced NF-kB signaling.

Photobiomodulation with 660-nm and 780-nm laser on activated J774 macrophage-like cells: Effect on M1 inflammatory markers

“…However, these same authors [53] also showed that 810-nm laser (0.3, 3, and 30 J/cm 2 ) reduced the level of expression of several inflammatory markers in bone marrow derived dendritic cells (a macrophage-lineage cell type) that had been pre-activated with CpG (a toll like receptor 9 agonist).…”

Improved Cognitive Function After Transcranial, Light-Emitting Diode Treatments in Chronic, Traumatic Brain Injury: Two Case Reports

“…47 In stimulated dendritic cells in the longer term, however, NF-kB and pro-inflammatory cytokines were reduced. 48 Thus, in the long-term, repeated LED treatments are hypothesized to decrease inflammation (less NF-kB), and up-regulate gene products that are cytoprotective, such as superoxide dismutase, glutathione peroxidase, and heat shock protein 70. 24,25,49,50 It is hypothesized that an overall protective response occurs with repeated LED treatments, with a reduction in major ROS-mediated damage and chronic inflammation known to occur in the brain after TBI.…”

Transcranial Low-Level Laser (Light) Therapy for Brain Injury

“…27 This protective effect may include several mediators such as Bcl2, heat shock proteins, 28 survivin, 29 and superoxide dismutase. 30 The decrease of proinflammatory mediators from dendritic cells 31 along with the increase in anti-inflammatory mediators [interleukin (IL)-10 and transforming growth factor b]…”