Santoro Domenico, Marsella Rosanna, Bunick David, Graves Thomas K, Campbell Karen L
Department of Veterinary Clinical Medicine, University of Illinois at Urbana-Champaign, Urbana, IL 61802, USA.
Vet Immunol Immunopathol. 2011 Dec 15;144(3-4):382-8. doi: 10.1016/j.vetimm.2011.08.004. Epub 2011 Aug 17.
Antimicrobial peptides (AMPs) are small immuno-modulatory proteins important in defense against pathogenic organisms. Defensins and cathelicidin are the most frequently studied human AMPs. An increase in AMPs in atopic humans has been reported recently. Our goals were to determine the distribution of AMPs and evaluate their mRNA and protein expression in non-lesional (Day 0), acute lesional skin (Day 3) and post-challenged skin after resolution of skin lesions (Day 10) using a canine model of atopic dermatitis (AD). All dogs were environmentally challenged for three consecutive days with house dust mite. Clinical evaluation of atopic beagles was performed using a CADESI score at each time point before and after environmental challenge. Skin biopsies were taken from six healthy and seven atopic beagles before and after allergen challenge (Day 0, Day 3 and Day 10). The transcription of canine cathelicidin (cCath) and beta-defensins (cBD)-1, -2 and -3 mRNA was quantified using quantitative-RT-PCR while the protein distribution of cBD2, cBD3 and cCath was detected by indirect immunofluorescence. A significant effect, over-time, was seen in CADESI score in AD beagles with an increase score after challenge (Day 3). Quantitative analysis showed a significant difference in mRNA transcript levels between groups (with atopic dogs having more than controls) for all AMPs but cBD2. No effect over time was evident for either group. No significant differences were seen for the AMP protein patterns of distribution (homogenous distribution). Although, these results showed no differences in AMP's localization after allergen exposure in each group; atopic dogs had a higher mRNA expression of AMPs when compared with healthy dogs, a similar finding to humans.
抗菌肽（AMPs）是一类小型免疫调节蛋白，在抵御病原生物方面发挥着重要作用。防御素和cathelicidin是研究最为频繁的人类抗菌肽。最近有报道称特应性个体体内的抗菌肽有所增加。我们的目标是利用特应性皮炎（AD）犬模型，确定抗菌肽在非皮损（第0天）、急性皮损皮肤（第3天）以及皮损消退后的激发后皮肤（第10天）中的分布情况，并评估其mRNA和蛋白表达。所有犬只连续三天接受屋尘螨环境激发。在环境激发前后的每个时间点，使用CADESI评分对特应性比格犬进行临床评估。在过敏原激发前后（第0天、第3天和第10天），从6只健康比格犬和7只特应性比格犬身上采集皮肤活检样本。使用定量逆转录聚合酶链反应（quantitative-RT-PCR）对犬cathelicidin（cCath）和β-防御素（cBD）-1、-2和-3的mRNA转录进行定量，同时通过间接免疫荧光检测cBD2、cBD3和cCath的蛋白分布。特应性比格犬的CADESI评分随时间有显著变化，激发后（第3天）评分增加。定量分析显示，除cBD2外，所有抗菌肽在各组之间的mRNA转录水平存在显著差异（特应性犬的水平高于对照组）。两组随时间均未观察到明显影响。抗菌肽的蛋白分布模式（均匀分布）未见显著差异。虽然这些结果表明各组在过敏原暴露后抗菌肽的定位没有差异；但与健康犬相比，特应性犬的抗菌肽mRNA表达更高，这一发现与人类相似。
