Differential toll like receptor expression in cystic fibrosis patients' airways during rhinovirus infection. Issue 5 (November 2020)

• Record Type: Journal Article
• Authors: Scagnolari, Carolina; Bitossi, Camilla; Frasca, Federica; Viscido, Agnese; Brazzini, Gabriele; Trancassini, Maria; Pietropaolo, Valeria; Midulla, Fabio; Cimino, Giuseppe; Palange, Paolo; Pierangeli, Alessandra; Antonelli, Guido
• Is Part Of: Journal of infection. Volume 81:Issue 5(2020)
• Page Start: 726
• Page End: 735
• Publication Date: 2020-11
• Subjects: Cystic fibrosis -- Rhinovirus -- Toll like receptors -- Viral load -- Virus-bacteria interaction; Infection -- Periodicals; Bacterial Infections -- Periodicals; Communicable Diseases -- Periodicals; Electronic journals; 616.905
• DOI: 10.1016/j.jinf.2020.07.021
• Languages: English
• ISSNs: 0163-4453

Abstract

Highlights: HRV is frequently found in the respiratory tract of CF patients. HRV can be associated to pulmonary exacerbations in CF patients. HRV load did not vary according to CF patients age. HRV infection affects the expression of TLRs in CF patients. TLR2 and TLR4 levels are increased in HRV positive CF patients. TLRs expression changed according to the specific HRV-bacteria species interaction. Summary: Objectives: Since an inappropriate and sustained activation of TLRs may contribute to a chronic inflammatory response resulting in detrimental effects in cystic fibrosis (CF) patients, we sought to examine whether HRV infection might alter the respiratory expression of TLRs according to the microbiological status of CF patients. Methods: Respiratory samples were collected from the respiratory tract of CF patients ( n = 294) over a period of 12 months. In addition to the usual microbiological investigation, HRV-RNA detection and typing were performed by RT-PCR and sequencing. HRV viral load and TLRs levels were measured by RT-Real Time PCR. Results: HRV-RNA was detected in 80 out of 515 respiratory samples (15.5%) with a similar rate in all age groups (0–10 years, 11–24 years, ≥ 25 years). Patients infected with different HRV A, B and C species exhibited higher levels of TLR2, TLR4 and TLR8 as compared to HRV negative patients. Moreover, the expression level of TLR2, TLR4 and TLR8 correlated with high level of HRV viral load. HRV positive patients co-colonized by Staphylococcus aureus or Pseudomonas aeruginosa showed also enhanced amounts of TLR2 and TLR2/4-mRNAs expression respectively. In the case of presence of both bacteria, TLR2, TLR4, TLR8 and TLR9 levels are elevated in positive HRV patients. Conclusions: TLRs, especially TLR2 and TLR4, increased in HRV positive CF individuals and varies according to the presence of S. aureus, P. aeruginosa and both bacteria. Graphical abstract: Image, graphical abstract