de Oliveira Rodrigo Guerra, Aarestrup Fernando Monteiro, Miranda Caio, Vieira Beatriz Julião, Ferreira Ana Paula, Andrade Luis Carlos
Faculty of Medical and Health Sciences, SUPREMA, Juiz de Fora, MG, Brazil.
Photomed Laser Surg. 2010 Dec;28(6):773-7. doi: 10.1089/pho.2009.2684. Epub 2010 Oct 22.
The aim of this study was to evaluate the effect of low-level laser therapy (LLLT) in an experimental model of delayed hypersensitivity reaction (DTH). LLLT has been used clinically to treat numerous diseases and has been tested in different experimental models, but some of its effects have yet to be explained. We assessed the effects of LLLT on DTH to ovalbumin (OVA), a protein that has commonly been used as an antigen to sensitize laboratory animals. This experimental model is broadly used to assess the effects of substances that can potentially modulate the immune system and inflammatory reactions. Balb/C mice were randomly divided into four groups: (I) immunized, untreated, and challenged (n = 6); (II) not immunized, untreated, and challenged (n = 6); (III) immunized, treated with azathioprine (AZA), and challenged (n = 6); and (IV) immunized, treated with LLLT, and challenged (n = 6). Forty-eight hours after the challenge, the animals were submitted to a paw edema test and euthanized for histopathology analysis of their plantar pads. The results obtained in DTH units were as follows: Group I, 19.6 ± 8.9; Group II, 5.8 ± 2.6; Group III, 5.6 ± 2.5; and Group IV, 5.2 ± 2.6. DTH was less intense for the groups treated with AZA and laser compared with Group I (p < 0.05). We observed no statistical difference between the AZA- and LLLT-treated groups. The slides obtained from the footpad specimens showed that AZA and laser acted similarly on the normal pattern of DTH triggering. Our results suggest that treatment with LLLT has an immunomodulatory effect on DTH to OVA.
本研究的目的是评估低强度激光疗法（LLLT）在迟发型超敏反应（DTH）实验模型中的效果。LLLT已在临床上用于治疗多种疾病，并已在不同的实验模型中进行了测试，但其一些效果尚未得到解释。我们评估了LLLT对卵清蛋白（OVA）诱导的DTH的影响，OVA是一种常用作使实验动物致敏的抗原的蛋白质。该实验模型广泛用于评估可能调节免疫系统和炎症反应的物质的效果。将Balb/C小鼠随机分为四组：（I）免疫、未治疗且接受激发（n = 6）；（II）未免疫、未治疗且接受激发（n = 6）；（III）免疫、用硫唑嘌呤（AZA）治疗且接受激发（n = 6）；以及（IV）免疫、用LLLT治疗且接受激发（n = 6）。激发后48小时，对动物进行爪部水肿试验，并实施安乐死以对其足底垫进行组织病理学分析。在DTH单位中获得的结果如下：第一组，19.6±8.9；第二组，5.8±2.6；第三组，5.6±2.5；第四组，5.2±2.6。与第一组相比，用AZA和激光治疗的组的DTH强度较低（p < 0.05）。我们观察到用AZA治疗的组和用LLLT治疗的组之间没有统计学差异。从足垫标本获得的玻片显示，AZA和激光对DTH触发的正常模式的作用相似。我们的结果表明，用LLLT治疗对OVA诱导的DTH具有免疫调节作用。
