Fc γ receptor IIIa/CD16a processing correlates with the expression of glycan-related genes in human natural killer cells.
Fc γ receptor IIIa/CD16a processing correlates with the expression of glycan-related genes in human natural killer cells.
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DOI：
10.1074/jbc.ra120.015516
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发表时间：
2021-01
期刊：
影响因子：
--
通讯作者：
Barb AW
中科院分区：
文献类型：
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作者：
Patel KR;Rodriguez Benavente MC;Lorenz WW;Mace EM;Barb AW
许多治疗性单克隆抗体需要与Fc γ受体（Fcγ R）结合才能发挥全部作用，增加结合亲和力可提高疗效。在5种活化人Fcγ R中，最突出的是自然杀伤（NK）细胞表达的FcγRIIIa/CD 16 a。CD 16 a被大量加工，最近的报告表明，五种CD 16 a天冬酰胺（N）连接的碳水化合物（聚糖）的组成影响亲和力。这些观察结果表明，对表达CD 16 a的效应细胞（包括NK细胞）中的CD 16 a N-聚糖组成进行特异性操作可改善治疗功效。然而，目前尚不清楚在表达CD 16 a的效应细胞中修饰编码加工酶的选择基因的表达是否足以影响N-聚糖组成。我们使用糖蛋白组学方法，通过比较从两种NK细胞系NK 92和YTS分离的CD 16 a与HEK 293 F细胞表达的CD 16 a以及先前报道的来自原代NK细胞的CD 16 a，确定了实质性的加工差异。通过RNA-Seq和qRT-PCR进行的基因表达谱分析揭示了与CD 16 a聚糖组成相关的聚糖修饰基因的表达水平。这些结果鉴定了不同人类细胞类型对相同人类蛋白质的加工之间的高度可变性。N-聚糖加工与聚糖修饰基因的表达相关，因此解释了不同来源的NK细胞在CD 16 a加工中的实质性差异。
Many therapeutic monoclonal antibodies require binding to Fc γ receptors (FcγRs) for full effect and increasing the binding affinity increases efficacy. Preeminent among the five activating human FcγRs is FcγRIIIa/CD16a expressed by natural killer (NK) cells. CD16a is heavily processed, and recent reports indicate that the composition of the five CD16a asparagine(N)-linked carbohydrates (glycans) impacts affinity. These observations indicate that specific manipulation of CD16a N-glycan composition in CD16a-expressing effector cells including NK cells may improve treatment efficacy. However, it is unclear if modifying the expression of select genes that encode processing enzymes in CD16a-expressing effector cells is sufficient to affect N-glycan composition. We identified substantial processing differences using a glycoproteomics approach by comparing CD16a isolated from two NK cell lines, NK92 and YTS, with CD16a expressed by HEK293F cells and previous reports of CD16a from primary NK cells. Gene expression profiling by RNA-Seq and qRT-PCR revealed expression levels for glycan-modifying genes that correlated with CD16a glycan composition. These results identified a high degree of variability between the processing of the same human protein by different human cell types. N-glycan processing correlated with the expression of glycan-modifying genes and thus explained the substantial differences in CD16a processing by NK cells of different origins.