Fukushima Atsuki, Yamaguchi Tomoko, Ishida Waka, Fukata Kazuyo, Ozaki Akemi, Ueno Hisayuki
Department of Ophthalmology, Kochi Medical School, Kochi University, Kohasu, Oko-cho, Nankoku-city 783-8505, Japan.
Immunol Lett. 2005 Sep 15;100(2):189-94. doi: 10.1016/j.imlet.2005.04.012.
Studies with interferon-gamma knockout (GKO) mice showed that endogenous IFN-gamma suppresses the infiltration of inflammatory cells into the conjunctiva. To examine whether this phenomenon is universally true, we induced conjunctival inflammation by four different immunization protocols.
Both wild type (WT) and GKO mice (C57BL/6 background) were immunized with ragweed (RW) in aluminum hydroxide (alum). Two different immunization protocols were used: either the emulsion was injected into only the left hind footpad or it was also injected into the tail base (50 microg RW in 2mg alum per injection site). In addition, to compare the effects of the immunization dose of RW and the immunization site, 100 microg RW in 2mg alum was injected into only the left hind footpad and 25 microg RW in 2mg alum per injection site was injected into both the left hind footpad and the tail base. Ten days later, the mice were challenged with 2mg RW in 10 microl PBS. Twenty-four hours later, the conjunctivas were analyzed histologically, and the cellular and humoral immune responses in the spleens and sera were determined, respectively.
Similar to a previous report, GKO mice showed significant eosinophilic infiltration into the conjunctiva after the footpad only injection of 50 microg RW. However, injection of 50 microg RW per injection site into the footpad plus the tail base resulted in comparable levels of eosinophilic infiltration in WT and GKO mice. On the contrary, either immunization of 100 microg RW in 2mg alum into only the left hind footpad or that of 25 microg RW in 2mg alum into both the left hind footpad and the tail base induced significant infiltration of eosinophils into the conjunctiva of GKO mice, compared to WT mice.
These results show that the immunization protocol employed has a marked effect on the severity of eosinophilic infiltration. These observations indicate that in interpreting experimental results in the study of EC, the immunization protocol employed must be considered.
对干扰素-γ基因敲除（GKO）小鼠的研究表明，内源性干扰素-γ可抑制炎性细胞向结膜的浸润。为了检验这一现象是否普遍成立，我们通过四种不同的免疫方案诱导结膜炎症。
野生型（WT）和GKO小鼠（C57BL/6背景）均用氢氧化铝（明矾）佐剂中的豚草（RW）进行免疫。采用了两种不同的免疫方案：乳液仅注射到左后足垫，或者也注射到尾基部（每个注射部位2mg明矾中含50μg RW）。此外，为了比较RW免疫剂量和免疫部位的影响，将2mg明矾中含100μg RW仅注射到左后足垫，将每个注射部位2mg明矾中含25μg RW注射到左后足垫和尾基部。10天后，用10μl PBS中含2mg RW对小鼠进行攻击。24小时后，对结膜进行组织学分析，并分别测定脾脏和血清中的细胞免疫和体液免疫反应。
与之前的报告相似，仅在足垫注射50μg RW后，GKO小鼠结膜出现明显的嗜酸性粒细胞浸润。然而，每个注射部位向足垫加尾基部注射5μg RW导致WT和GKO小鼠的嗜酸性粒细胞浸润水平相当。相反，与WT小鼠相比，将2mg明矾中含100μg RW仅免疫左后足垫，或将每个注射部位2mg明矾中含25μg RW免疫左后足垫和尾基部，均可诱导GKO小鼠结膜出现明显的嗜酸性粒细胞浸润。
这些结果表明，所采用的免疫方案对嗜酸性粒细胞浸润的严重程度有显著影响。这些观察结果表明，在解释眼部变态反应性疾病研究中的实验结果时，必须考虑所采用的免疫方案。
