van den Broek A H M, Else R W, Huntley J F, Machell J, Taylor M A, Miller H R P
Department of Veterinary Clinical Studies, Royal (Dick) School of Veterinary Studies, University of Edinburgh, Easter Bush Veterinary Centre, Easter Bush, Roslin, Midlothian EH25 9RG, UK.
J Comp Pathol. 2004 Nov;131(4):318-29. doi: 10.1016/j.jcpa.2004.05.005.
Clinical observation has indicated that Psoroptes ovis mites provoke cutaneous inflammation within hours of experimental infestation, but the nature of this reaction has not been described. After infestation of naive sheep with ovigerous P. ovis mites, significant influxes of eosinophils (P<0.004) and neutrophils (P<0.001) were detected within 24 h. A significant (P<0.001) increase in mast cell numbers was observed by 96 h post-infestation. In addition, marked degenerative and proliferative epidermal lesions were evident 24 and 96 h, respectively, after infestation. The influence of the later, adaptive response on the cellular infiltrate at the advancing margin of the lesion and the original site of infestation was also monitored. Mast cell numbers were greatest at 21 days while recruitment of eosinophils and neutrophils was maximal 63 days after infestation. Lesional severity was particularly pronounced from 42 to 63 days after infestation, but significant resolution had occurred by 84 days. Pathological changes at the advancing margin of the lesion were more severe than at the initial site of infestation, and this was reflected by the numbers of mites present. These data suggest that P. ovis elicits an early innate cutaneous response that is subsequently augmented by the development of an adaptive immune response, the intensity of which corresponds to the local population density of mites.
临床观察表明，绵羊痒螨在实验性侵染数小时内即可引发皮肤炎症，但这种反应的性质尚未得到描述。用携带卵的绵羊痒螨侵染未感染的绵羊后，在24小时内检测到嗜酸性粒细胞（P<0.004）和中性粒细胞（P<0.001）大量涌入。侵染后96小时观察到肥大细胞数量显著增加（P<0.001）。此外，侵染后24小时和96小时分别出现明显的退行性和增殖性表皮病变。还监测了后期适应性反应对病变前缘和侵染原始部位细胞浸润的影响。肥大细胞数量在21天时最多，而嗜酸性粒细胞和中性粒细胞的募集在侵染后63天时达到最大。侵染后42至63天病变严重程度尤为明显，但到84天时已出现显著缓解。病变前缘的病理变化比侵染初始部位更严重，这由存在的螨数量反映出来。这些数据表明，绵羊痒螨引发早期先天性皮肤反应，随后适应性免疫反应的发展增强了这种反应，其强度与螨的局部种群密度相对应。
