Mbow M L, Rutti B, Brossard M
Institute of Zoology, University of Neuchâtel, Switzerland.
Cell Immunol. 1994 Jun;156(1):254-61. doi: 10.1006/cimm.1994.1170.
The skin and draining lymph nodes of BALB/c mice were examined for IFN-gamma, IL-2, and IL-4 mRNA expression by in situ hybridization in three successive infestations with nymphal Ixodes ricinus ticks. IFN-gamma and IL-2 mRNA positive cells were readily detected in lymph node sections during primary antigenic stimulation (72 hr post-tick attachment), whereas hybridization with IL-4 probe yielded no or only a faint positive signal. No changes in the cytokine pattern were observed in lymph node sections from reinfested mice, with IL-4 mRNA always being expressed to a lesser extent than IFN-gamma and IL-2 mRNA. Seventy-two hours post-tick attachment in primary infestation, some infiltrating cells in the skin were positive for IFN-gamma and IL-4 mRNA, but not for IL-2 mRNA. In skin sections of reinfested mice, mRNA coding for IFN-gamma, IL-2, and IL-4 were detected in infiltrating cells. Cells positive for IL-4 mRNA were lower in number than those positive for IFN-gamma and IL-1 mRNA. A significant decrease in the number of IL-4 mRNA positive cells in the tertiary infestation was noted. All together, these results indicate that I. ricinus nymphal ticks antigens are able to elicit expression of IFN-gamma, IL-2 mRNA and to a lesser extent IL-4 mRNA in both skin and draining lymph nodes. In addition, repeated infestations with ticks led to strong expression of IFN-gamma and IL-2 mRNAs in the skin that may be correlated with previous observations showing the occurrence of cutaneous delayed-type hypersensitivity in tick-infested mice. Notably, the cytokine pattern observed in the skin and draining lymph nodes is not associated with a protective immune response in mice against I. ricinus nymphal ticks infestations.
通过原位杂交法，对连续三次感染蓖麻硬蜱若虫的BALB/c小鼠的皮肤和引流淋巴结进行检测，以观察干扰素-γ（IFN-γ）、白细胞介素-2（IL-2）和白细胞介素-4（IL-4）mRNA的表达情况。在初次抗原刺激期间（蜱附着后72小时），在淋巴结切片中很容易检测到IFN-γ和IL-2 mRNA阳性细胞，而与IL-4探针杂交则未产生信号或仅产生微弱的阳性信号。在再次感染小鼠的淋巴结切片中未观察到细胞因子模式的变化，IL-4 mRNA的表达程度始终低于IFN-γ和IL-2 mRNA。在初次感染蜱后72小时，皮肤中的一些浸润细胞IFN-γ和IL-4 mRNA呈阳性，但IL-2 mRNA呈阴性。在再次感染小鼠的皮肤切片中，浸润细胞中检测到编码IFN-γ、IL-2和IL-4的mRNA。IL-４mRNA阳性细胞的数量低于IFN-γ和IL-1 mRNA阳性细胞。在第三次感染中，观察到IL-4 mRNA阳性细胞数量显著减少。总之，这些结果表明，蓖麻硬蜱若虫抗原能够在皮肤和引流淋巴结中诱导IFN-γ、IL-2 mRNA的表达，并在较小程度上诱导IL-4 mRNA的表达。此外，蜱的反复感染导致皮肤中IFN-γ和IL-2 mRNAs的强烈表达，这可能与先前观察到的蜱感染小鼠中发生皮肤迟发型超敏反应有关。值得注意的是，在皮肤和引流淋巴结中观察到的细胞因子模式与小鼠针对蓖麻硬蜱若虫感染的保护性免疫反应无关。
