Low-level laser reduces the production of TNF-α, IFN-γ, and IL-10 induced by OVA

Abstract

Delayed, or type IV, hypersensitivity reactions are a useful model to study the effects of new substances on the immune system. In this study, the experimental model of the delayed type hypersensitivity (DTH) reaction to ovalbumin (OVA) was used to evaluate the immunomodulating effects of low-level laser therapy (LLLT), which is used as an adjuvant therapy in medicine, dentistry, and physical therapy because of its potential anti-inflammatory and analgesic effects observed in several studies. The effects of LLLT (λ 780 nm, 0.06 W/cm(2) of radiation, and fluency of 3.8 J/cm(2)) in reaction to ovalbumin in Balb/C mice were examined after the induction phase of the hypersensitivity reaction. The animals treated with azathioprine (AZA), the animals that received a vehicle instead of ovalbumin, and those not immunized served as controls (n = 6 for each group). Footpad thickness measurements and hematoxylin-eosin histopathological exams were performed. Proliferation tests were also performed (spontaneous, in the presence of concanavalin A and ovalbumin) to determine the production in mononuclear cells cultures of tumor necrosis factor-alpha (TNF-α), INF-γ, and IL-10. In the group of animals irradiated with lasers and in the group treated with AZA, footpad thickness measurements were significantly reduced in comparison to the control group (p < 0.05). This reduction was accompanied by a very significant reduction in the density of the inflammatory infiltrate and by a significant reduction in the levels of TNF-α, INF-γ, and IL-10. LLLT radiation was shown to have an immunomodulating effect on DTH to OVA in Balb/C mice.

Complicated Effect of He-Ne Laser Therapy on Pro-/Anti-Inflammatory Cytokines from Serum in Rats

“…Previous study observed a reduction of IL-10 at 6 and 12 h after laser treatment, without statistically significant [12]. Level of IL-10 produced by mesenteric and periaortic lymph node cells from mice after 6 days of laser treatment was also reduced [28]. However, the present studies showed that the level of IL-10 increases in He-Ne laser treatment group.…”

Comparative study among three different phototherapy protocols to treat chemotherapy‐induced oral mucositis in hamsters

“…Regarding the proinflammatory cytokine responsible for inducing inflammation and epithelial damage, Groups LL and L presented lower expression of TNF‐α, on the 7 th day of the experiment, when compared with the Groups CH and HL. These data contributed to the hypothesis that the treatment with LLLT and LED alter normal immunological response pattern by inhibiting the production of cytokines responsible for initiating and maintaining the inflammatory response and consequently, reducing the severity of the OM lesions . Furthermore, the LLLT can modulate the activity of macrophages, a connective tissue cell responsible for releasing TNF‐α .…”

Effect of laser therapy on immune cells infiltrate after excisional wounds in diabetic rats

“…Although, many factors likely contribute to the macrophage dysfunction found in individuals with diabetes, the increase in the amount of the pro‐ inflammatory cytokines interferon gamma and IL‐1β, along with a decrease in the amount the anti‐inflammatory IL‐10, may play a significant role . As macrophages are light‐sensitive cells that can be modulated both in the red light and near infrared range, PBM may partially restore the balance of this microenvironment due to the reduction in interferon , IL‐1 and oxidative stress markers in healing tissues.…”