Durazo-Martinez Kassandra, Chaudhari Jayeshbhai, Kumari Sushmita, Vu Hiep L X
Department of Animal Science and Nebraska Center for Virology, University of Nebraska-Lincoln, Lincoln, NE, United States.
School of Veterinary Science and Nebraska Center for Virology, University of Nebraska-Lincoln, Lincoln, NE, United States.
Front Microbiol. 2024 Dec 11;15:1505900. doi: 10.3389/fmicb.2024.1505900. eCollection 2024.
Previous studies have suggested that porcine peritoneal macrophages (PPMs) are resistant to PRRSV infection, whereas porcine alveolar macrophages (PAMs) are highly susceptible. This contrast is intriguing, as both cell types belong to the same monocyte/macrophage family. The current study aimed to investigate the host factors contributing to the differing susceptibility of PPMs and PAMs to PRRSV infection. We found that PPMs exhibit a higher frequency of CD14 cells compared to PAMs, suggesting a more immature macrophage phenotype in PPMs. Importantly, PPMs expressed both CD163 and CD169, the key receptors for PRRSV entry, although the frequency and intensity of CD163 and CD169 expression were lower in PPMs than in PAMs. Despite these differences, PPMs were susceptible to both PRRSV-1 and PRRSV-2 isolates. Notably, PPMs susceptibility increased 10-fold when the cells were cultured for 1 day before infection. PRRSV infection in PPMs was dependent on CD163, as pretreatment with an anti-CD163 antibody significantly reduced infection. Overall, our results demonstrate that PPMs are susceptible to PRRSV infection, thereby expanding the understanding of PRRSV tropism.
先前的研究表明，猪腹膜巨噬细胞（PPM）对猪繁殖与呼吸综合征病毒（PRRSV）感染具有抗性，而猪肺泡巨噬细胞（PAM）则高度易感。这种差异很有趣，因为这两种细胞类型都属于同一个单核细胞/巨噬细胞家族。当前的研究旨在调查导致PPM和PAM对PRRSV感染易感性不同的宿主因素。我们发现，与PAM相比，PPM中CD14细胞的频率更高，这表明PPM具有更不成熟的巨噬细胞表型。重要的是，PPM表达了PRRSV进入的关键受体CD163和CD169，尽管PPM中CD163和CD169表达的频率和强度低于PAM。尽管存在这些差异，PPM对PRRSV-1和PRRSV-2分离株均易感。值得注意的是，在感染前将细胞培养1天，PPM的易感性增加了10倍。PPM中的PRRSV感染依赖于CD163，因为用抗CD163抗体预处理可显著降低感染率。总体而言，我们的结果表明PPM对PRRSV感染易感，从而扩展了对PRRSV嗜性的理解。
