Griggs Theodor F, Bochkov Yury A, Basnet Sarmila, Pasic Thomas R, Brockman-Schneider Rebecca A, Palmenberg Ann C, Gern James E
Department of Pediatrics, School of Medicine and Public Health, CSC K4/945, 600 Highland Ave, Madison, 53792, WI, USA.
Cellular & Molecular Pathology Graduate Program, Madison, WI, USA.
Respir Res. 2017 May 4;18(1):84. doi: 10.1186/s12931-017-0567-0.
The Rhinovirus C (RV-C), first identified in 2006, produce high symptom burdens in children and asthmatics, however, their primary target host cell in the airways remains unknown. Our primary hypotheses were that RV-C target ciliated airway epithelial cells (AECs), and that cell specificity is determined by restricted and high expression of the only known RV-C cell-entry factor, cadherin related family member 3 (CDHR3).
RV-C15 (C15) infection in differentiated human bronchial epithelial cell (HBEC) cultures was assessed using immunofluorescent and time-lapse epifluorescent imaging. Morphology of C15-infected differentiated AECs was assessed by immunohistochemistry.
C15 produced a scattered pattern of infection, and infected cells were shed from the epithelium. The percentage of cells infected with C15 varied from 1.4 to 14.7% depending on cell culture conditions. Infected cells had increased staining for markers of ciliated cells (acetylated-alpha-tubulin [aat], p < 0.001) but not markers of goblet cells (wheat germ agglutinin or Muc5AC, p = ns). CDHR3 expression was increased on ciliated epithelial cells, but not other epithelial cells (p < 0.01). C15 infection caused a 27.4% reduction of ciliated cells expressing CDHR3 (p < 0.01). During differentiation of AECs, CDHR3 expression progressively increased and correlated with both RV-C binding and replication.
The RV-C only replicate in ciliated AECs in vitro, leading to infected cell shedding. CDHR3 expression positively correlates with RV-C binding and replication, and is largely confined to ciliated AECs. Our data imply that factors regulating differentiation and CDHR3 production may be important determinants of RV-C illness severity.
鼻病毒C（RV-C）于2006年首次被发现，在儿童和哮喘患者中会产生严重的症状负担，然而，它们在气道中的主要靶宿主细胞仍然未知。我们的主要假设是，RV-C靶向气道纤毛上皮细胞（AECs），并且细胞特异性由唯一已知的RV-C细胞进入因子钙黏蛋白相关家族成员3（CDHR3）的受限且高表达所决定。
使用免疫荧光和延时落射荧光成像评估分化的人支气管上皮细胞（HBEC）培养物中RV-C15（C15）的感染情况。通过免疫组织化学评估C15感染的分化AECs的形态。
C15产生分散的感染模式，并且受感染的细胞从上皮脱落。根据细胞培养条件，感染C15的细胞百分比在1.4%至14.7%之间变化。受感染细胞中纤毛细胞标志物（乙酰化α微管蛋白[aat]）的染色增加（p<0.001），但杯状细胞标志物（麦胚凝集素或Muc5AC，p=无显著性差异）的染色未增加。CDHR3在纤毛上皮细胞上的表达增加，但在其他上皮细胞上未增加（p<0.01）。C15感染导致表达CDHR3的纤毛细胞减少27.4%（p<0.01）。在AECs分化过程中，CDHR3表达逐渐增加，并且与RV-C结合和复制均相关。
RV-C仅在体外的纤毛AECs中复制，导致受感染细胞脱落。CDHR3表达与RV-C结合和复制呈正相关，并且主要局限于纤毛AECs。我们的数据表明，调节分化和CDHR3产生的因素可能是RV-C疾病严重程度的重要决定因素。
