Primary airway epithelial cultures from children are highly permissive to respiratory syncytial virus infection

Abstract

Background Respiratory syncytial virus (RSV) infection of airway epithelial cells (AECs) is an important initial event in RSV bronchiolitis. AEC immunological responses are thought to be critical in driving the subsequent inflammation in the airway. This study examined viral replication, cytotoxicity and cytokine production in cultures of primary AECs from children compared with responses to RSV infection in an immortalised epithelial cell line and to those from infants with RSV bronchiolitis. Methods RSV replication, proinflammatory cytokine responses and cytotoxicity in RSV-infected primary AEC cultures derived from bronchial brushings from the lungs of children were compared with those seen in BEAS-2B cultures, as well as AECs and bronchoalveolar lavage fluid collected from children with and without RSV bronchiolitis. Results Viral replication, cytotoxicity and inflammatory cytokine production were greater in primary AEC cultures than in BEAS-2B cells. Different response patterns were observed, with RSV infection of primary AEC cultures causing distinct peaks of viral replication and matched cytotoxic responses. Some primary AEC culture immunological responses, such as interleukin 8, were similar in magnitude to those seen in clinical samples from the lungs of children with RSV bronchiolitis. Although variable amounts of RSV were detected by PCR in freshly isolated primary AECs, RSV was not detected by immunocytochemistry. Conclusion This is one of the first studies to examine comprehensively the responses to RSV infection in primary AEC cultures from children and shows marked differences from those of a commercially available immortalised human cell line but reassuring similarities to results found in vivo. This suggests that future work investigating responses of AECs to RSV infection should use primary AEC cultures.

Infantile respiratory syncytial virus and human rhinovirus infections: respective role in inception and persistence of wheezing

“…Mucus secretion increases in both quantity and viscosity and, when mixed with cellular debris and fibrin, severe obstruction of the airway lumen occurs. Airway epithelial cells appear to be highly permissive to RSV, as demonstrated by the high viral replication and the cell cytotoxicity observed after experimental exposure of human bronchial epithelial cells (BECs) to the virus [36]. In air-liquid interface cultures, generated from nasal and bronchial brushes from healthy preschool children, RSV infection appeared to be localised to apical ciliated epithelial cells, with no detectable infection of goblet cells [37].…”

CX3CR1 is an important surface molecule for respiratory syncytial virus infection in human airway epithelial cells

“…It has been shown that RSV infection of human airway epithelial cells (HAECs) induces strong cytokine/ chemokine responses, including production of IL-1b, IL-6, IL-8, IP-10, macrophage inflammatory protein (MIP)-1a, monocyte chemotactic protein (MCP)-1 and RANTES (regulated on activation normal T-cell expressed and secreted) (Fonceca et al, 2012;Ioannidis et al, 2012;Olszewska-Pazdrak et al, 1998;Oshansky et al, 2010;Tristram et al, 1998;Villenave et al, 2011), and these cytokines and released viral proteins influence the host immune response to RSV (Chirkova et al, 2013;Ioannidis et al, 2012;McNamara et al, 2013;Qin et al, 2011). RSV G protein has been shown to impair innate and memory immune responses, such as suppressing production of IFN-b (Shingai et al, 2008), lymphoproliferation of T-cells (Ray et al, 2001), and responsiveness of monocytes/macrophages and dendritic cells (Johnson et al, 2012;Polack et al, 2005).…”

Respiratory Syncytial Virus Infection: Mechanisms of Redox Control and Novel Therapeutic Opportunities

“…Studies of genetic polymorphism (mostly single-nucleotide polymorphism [SNP]) for single chemokine and chemokine receptor genes, including IL-8, IL-8 receptor, RANTES, CCR5 receptor (for RANTES and MIP-1a), and their association with RSV disease severity have been so far inconclusive, based on the fact that these studies have not been confirmed in more than one population or have reported conflicting results [reviewed in (170)]. Greater scientific consensus on the other hand exists in the recognition of respiratory epithelial cells as a major initiator and a modifier of host innate responses and inflammation by secreting chemokines in response to RSV infection (75,81,95,183,203). Most of these studies have been performed in cell culture, but some studies have shown RSV-mediated expression of chemokines in airway epithelial cells in vivo (95).…”

“…At that point, infection may be self-limited or may spread to the lower respiratory tract in part by a cell-to-cell transfer of the virus along intracytoplasmic bridges (96), although the mechanism by which RSV reaches the lower airway is not clearly defined, as the distribution of infected cells in LRTI is patchy. Thus, the epithelium of the respiratory mucosa, the main function of which is to provide a protective physical barrier against injurious inhaled stimuli, is clearly the main target of RSV replication, as shown by studies of infected patients (178,250), experimental murine models (224), and by a variety of different in vitro culture systems (75,185,203,258) (Fig. 1).…”