Sialylation of IgE does not impact its interaction with FcεRI.
Sialylation of IgE does not impact its interaction with FcεRI.
复制标题
IgE 的唾液酸化不会影响其与 FcγRI 的相互作用。
DOI：
10.1111/all.16014
复制
发表时间：
2024
期刊：
影响因子：
12.4
通讯作者：
Anthony,RobertM
中科院分区：
文献类型：
--
作者：
Banerjee,Sayantan;Phelan,ColleenP;Reese,BrianB;Conroy,MichelleE;Anthony,RobertM
IgE 以高亲和力单体结合 FcεRI。 1-4 最近的一份手稿使用夹心 ELISA 和流式细胞术询问了 IgE 和 FcεRI 之间的相互作用，这 5 种方法可以量化与 FcεRI 结合的 IgE 量，但不能量化相互作用强度。作者发现，在两项测定中，在饱和水平下，与 FcεRI 结合的去唾液酸化 IgE 比唾液酸化 IgE 更多。因此，我们询问去除唾液酸是否能够使多个 IgE 与 FcεRI 结合。我们按照所述用神经氨酸酶和缓冲液（唾液酸化 mIgE）或仅缓冲液（唾液酸化 mIgE）处理 α-OVA mIgE（图 1A）。 6 通过凝胶电泳和随后使用唾液酸特异性黑接骨木凝集素 (SNA) 进行凝集素印迹来确认消化（图 1B）。唾液酸化和去唾液酸化 mIgE 结合和饱和 OVA 类似（图 1C）。通过生物层干涉测量法（BLI，图 1D）对 mIgE 制剂进行实时人 FcεRI (hFcεRI) 结合测定。唾液酸化（粉色）和去唾液酸化（黄色）mIgE 之间的 FcεRI 结合相似，两种相互作用的建模与 1:1 相互作用一致（未显示）。接下来，我们在被动皮肤过敏反应 (PCA) 模型中测试了唾液酸化和去唾液酸化 mIgE，该模型对血清半衰期不敏感。事实上，用唾液酸化 mIgE 致敏的耳朵表现出强烈的炎症，而用去唾液酸化 IgE 治疗的耳朵中的炎症明显减弱（图 1E）。 6
IgE binds FcεRI monomerically with high affinity. 1–4 A recent manuscript interrogated interactions between IgE and FcεRI using sandwich ELISA and flow cytometry, 5 methods which quantify the amount of IgE bound to FcεRI, but not interaction strength. The authors found more asialylated IgE bound FcεRI than sialylated IgE at saturating levels in both assays. Therefore, we asked whether removing sialic acid enabled binding of multiple IgE to FcεRI.We treated α-OVA mIgE (Figure 1A) with neuraminidase and buffer (asialylated mIgE) or buffer-only (sialylated mIgE) as described. 6 Digestions were confirmed by gel electrophoresis followed by lectin blotting with sialic acid-specific Sambucus Nigra Lectin (SNA)(Figure 1B). Sialylated and asialylated mIgE bound and saturated OVA similarly (Figure 1C). The mIgE preparations were tested in real-time human FcεRI (hFcεRI) binding assays by biolayer interferometry (BLI, Figure 1D). FcεRI binding was similar between sialylated (pink) and asialylated (yellow) mIgE, and modeling of both interactions was consistent with a 1: 1 interaction (not shown). Next, we tested sialylated and asialylated mIgE in a model of passive cutaneous anaphylaxis (PCA), which is insensitive to serum half-life. Indeed, ears sensitized with sialylated mIgE exhibited robust inflammation, while inflammation in ears treated with asialylated IgE was markedly attenuated (Figure 1E). 6