RSV and HMPV Infections in 3D Tissue Cultures: Mechanisms Involved in Virus-Host and Virus-Virus Interactions

Abstract

Respiratory viral infections constitute a global public health concern. Among prevalent respiratory viruses, two pneumoviruses can be life-threatening in high-risk populations. In young children, they constitute the first cause of hospitalization due to severe lower respiratory tract diseases. A better understanding of their pathogenesis is still needed as there are no approved efficient anti-viral nor vaccine against pneumoviruses. We studied Respiratory Syncytial virus (RSV) and human Metapneumovirus (HMPV) in single and dual infections in three-dimensional cultures, a highly relevant model to study viral respiratory infections of the airway epithelium. Our investigation showed that HMPV is less pathogenic than RSV in this model. Compared to RSV, HMPV replicated less efficiently, induced a lower immune response, did not block cilia beating, and was more sensitive to IFNs. In dual infections, RSV-infected epithelia were less permissive to HMPV. By neutralizing IFNs in co-infection assays, we partially prevented HMPV inhibition by RSV and significantly increased the number of co-infected cells in the tissue. This suggests that interference in dual infection would be at least partly mediated by the host immune response. In summary, this work provides new insight regarding virus-host and virus-virus interactions of pneumoviruses in the airway epithelium. This could be helpful for the proper handling of at-risk patients.

In Vitro Modelling of Respiratory Virus Infections in Human Airway Epithelial Cells – A Systematic Review

“…CPE in primary HAEC dif often resembles the natural situation more closely compared to continuous cells. HRSV offers a good example: in continuous cell lines it forms big syncytia (hence the name), but in primary HAEC HRSV forms little to no syncytia, which is in line with observations in vivo (both animal models and humans) ( 48 , 122 , 129 , 168 – 170 ). A clinical observation in HRSV disease is neutrophil inflammation, which is involved in severe HRSV disease.…”

“…In response to influenza virus infection, similar cytokines, mainly IL-1β, IL-6 and IL-8, were produced in HAEC dif from different parts of the RT ( 114 , 116 – 118 ). For HRSV and HMPV infections it has also been shown that similar cytokines, predominantly type I and/or type III IFN, are produced in HAEC dif (nasal, bronchial and small airway) ( 123 , 126 – 132 , 168 ).…”

“…For instance, HRV-B infections are associated with less severe infections and studies in primary HAEC dif (nasal and bronchial) reported that HRV-B replicates slower and leads to less cytotoxicity than HRV-A and HRV-C (164,165). For both HRSV and HMPV it was confirmed in HAEC dif and AO dif mainly targets the ciliated epithelial cells (122,123,128,(166)(167)(168). One study showed that basal cells could also be infected by HRSV after epithelial injury, using commercially obtained primary HAEC dif (bronchial) (124).…”

Sequential infections with rhinovirus and influenza modulate the replicative capacity of SARS-CoV-2 in the upper respiratory tract

“…In order to study the effect of respiratory viruses on SARS-CoV-2 replication in multiple versus single infections, sequential infections were performed as previously described [ 17 , 18 ]. In a first set of co-infection assays ( Figure 1 A, upper panel), RV, IAV and IBV pre-infected tissues were inoculated with SARS-CoV-2 48 h after the primary (first) infection.…”

“…For dual infections, similar protocol was used for the second infection 1 or 2 days after the first one. In order to study the involvement of interferon (IFN), similar dual assays were repeated where a mixture of anti-type I neutralizing antibodies diluted 1/50 (39000-1, PBL Assay Science TM , Piscataway, NJ, USA) and 10μg/mL of anti-IFN-λ1 (MAB15981-100, RandD, Minneapolis, MN, USA), were added in the basolateral medium as previously described [ 17 , 18 ].…”