Arslan B A, Timucin A C
Acta Virol. 2020;64(4):389-395. doi: 10.4149/av_2020_401.
Severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) has caused fatal outbreaks of pneumonia. The similarity of S protein of SARS-CoV-2 with SARS-CoV and RaTG13 is about 76% and 97%, respectively. Also its potential receptor-binding domain (RBD) shows similarity with approximately 74% and 90.1% for SARS-CoV and RaTG13, respectively. SARS-CoV-2 has been shown to use the SARS-CoV receptor ACE2 for entry and serine protease TMPRSS2 for S protein priming. Sialic acids are primarily expressed by vertebrates and some microbial pathogens improving the ability to avoid immune system of vertebrate host. Interactions of sialic acid-binding Ig-like lectins (Siglecs) with their ligands play an important role in modulating immune cell function activities as their regulators. Therefore, while Siglecs help immune cells to distinguish between self and non-self, non-self ligands of some sialylated pathogens can recognize Siglecs and reduce immune cell responses or escape from immune surveillance. In this review, innate immunity in SARS-Cov-2 infection was discussed through Siglecs, especially Siglec-7, Siglec-3, NKG2A and neuraminidases. Keywords: SARS-Cov-2; siglecs; NK cells; NKG2A; neuraminidases.
严重急性呼吸综合征冠状病毒2（SARS-CoV-2）已引发致命的肺炎疫情。SARS-CoV-2的S蛋白与SARS-CoV和RaTG13的相似度分别约为76%和97%。其潜在的受体结合域（RBD）与SARS-CoV和RaTG13的相似度分别约为74%和90.1%。已证明SARS-CoV-2利用SARS-CoV的受体血管紧张素转换酶2（ACE2）进入细胞，并利用丝氨酸蛋白酶TMPRSS2对S蛋白进行启动。唾液酸主要由脊椎动物和一些微生物病原体表达，可提高其逃避脊椎动物宿主免疫系统的能力。唾液酸结合免疫球蛋白样凝集素（Siglecs）与其配体的相互作用作为调节剂在调节免疫细胞功能活动中起重要作用。因此，虽然Siglecs有助于免疫细胞区分自我和非自我，但一些唾液酸化病原体的非自我配体可以识别Siglecs并降低免疫细胞反应或逃避免疫监视。在本综述中，通过Siglecs，特别是Siglec-7、Siglec-3、NKG2A和神经氨酸酶，探讨了SARS-Cov-2感染中的固有免疫。关键词：SARS-Cov-2；Siglecs；自然杀伤细胞；NKG2A；神经氨酸酶。
