Sialoadhesin and CD163 join forces during entry of the porcine reproductive and respiratory syndrome virus
Sialoadhesin and CD163 join forces during entry of the porcine reproductive and respiratory syndrome virus
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DOI：
10.1099/vir.0.2008/005009-0
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发表时间：
2008-12-01
影响因子：
3.8
通讯作者：
Nauwynck, Hans J.
中科院分区：
文献类型：
--
作者：
Van Gorp, Hanne;Van Breedam, Wander;Nauwynck, Hans J.
猪繁殖与呼吸综合征病毒（PRRSV）在体内对猪巨噬细胞的亚群表现出有限的嗜性。迄今为止，已经在原代巨噬细胞上鉴定出两种PRRSV受体，硫酸乙酰肝素用于结合，唾液酸粘附素用于结合和内化。然而，需要额外的因素，因为两种受体在非允许细胞中的表达导致病毒内化，但不导致病毒脱壳和生产性感染。最近，CD 163被描述为Marc-145细胞上的PRRSV受体，其使得非允许细胞对PRRSV敏感。因此，研究了CD 163在PRRSV进入巨噬细胞中的潜在作用及其与唾液酸粘附素的潜在相互作用。巨噬细胞孵育;在37 ℃下，用唾液酸粘附素或CD 163特异性抗体将PRRSV感染降低高达75%，而感染被两种抗体的组合完全阻断。当在4 ℃下孵育时，只有唾液酸粘附素特异性抗体而不是CD 163特异性抗体降低了PRRSV感染。此外，共聚焦分析的PRRSV进入非允许的细胞只表达sialoadhesin显示PRRSV内化，但没有脱壳。相反，当唾液酸粘附素和CD 163都表达时，PRRSV在内化时未被包覆，导致生产性感染。当仅表达CD 163时，未观察到病毒内化;尽管如此，细胞变得富有成效地感染。因此，sialoadhesin被证实为一种PRRSV内化受体，CD 163被证明参与PRRSV进入，可能在脱壳过程中。与仅表达CD 163的细胞相比，在非允许细胞中共表达重组唾液酸粘附素和CD 163使病毒产量增加10-100倍，维持了有效的PRRSV感染对两者的需要。
The porcine reproductive and respiratory syndrome virus (PRRSV) shows a restricted tropism for subsets of porcine macrophages in vivo. To date, two PRRSV receptors have been identified on primary macrophages, heparan sulphate for binding and sialoadhesin for binding and internalization. However, additional factors are needed because the expression of both receptors in non-permissive cells results in virus internalization but not in virus uncoating and productive infection. Recently, CD163 was described as a PRRSV receptor on Marc-145 cells that renders non-permissive cells susceptible to PRRSV. Therefore, the potential role of CD163 in PRRSV entry in macrophages and its potential interplay with sialoadhesin were studied. Incubation of macrophages; at 37 degrees C with either sialoadhesin- or CD163-specific antibodies reduced PRRSV infection by up to 75%, while infection was completely blocked by a combination of both antibodies. When incubated at 4 degrees C, only sialoadhesin- and not CD163-specific antibodies reduced PRRSV infection. In addition, confocal analysis of PRRSV entry in non-permissive cells expressing only sialoadhesin showed PRRSV internalization but no uncoating. In contrast, when both sialoadhesin and CD163 were expressed, PRRSV was uncoated upon internalization, resulting in productive infection. Virus internalization was not observed when only CD163 was expressed; although, cells became productively infected. Thus, sialoadhesin is confirmed as a PRRSV internalization receptor and CD163 is shown to be involved in PRRSV entry, probably during uncoating. Co-expression of recombinant sialoadhesin and CD163 in non-permissive cells increased virus production 10-100 times compared with cells expressing only CD163, sustaining the requirement of both for efficient PRRSV infection.