Impaired virus replication and decreased innate immune responses to viral infections in nasal epithelial cells from patients with allergic rhinitis

Abstract

The aim of this study was to assess the immune response to parainfluenza virus type 3 (PIV3), rhinovirus 1B (RV1B) and intracellular Toll-like receptors (TLR) agonists in nasal epithelial cells (NECs) from patients with allergic rhinitis and healthy controls. NECs were obtained from eight patients with allergic rhinitis (AR) and 11 non-atopic healthy controls (HC) by nasal scraping, grown to confluence and exposed to PIV3, RV1B infection or TLR-3 and TLR-7/8 agonists. Interferon (IFN)-λ1, IFN-α, IFN-β and regulated on activation, normal T expressed and secreted (RANTES) release into the cell culture supernatants was assessed at 8, 24 and 48 h upon infection or 8 and 24 h after stimulation with poly(I:C) and R848. mRNA levels of IFNs, RANTES, interferon regulatory transcription factor (IRF)3, IRF7 and viral gene copy number were determined using real-time polymerase chain reaction (RT-PCR). PIV3 but not RV1B replication 48 h after infection was significantly lower (P < 0·01) in NECs from AR patients compared to HC. PIV3 infection induced significantly less IFN-λ1 (both protein and mRNA) in NECs from AR compared to HC. IFN-β mRNA expression and RANTES protein release and mRNA expression tended to be smaller in AR compared HC cells in response to both viruses. Stimulation with TLR-3 agonist [poly (I:C)] induced similar IFN-λ1 and RANTES generation in AR and HC subjects. Viral infections in NECs induced IRF7 expression, which correlated with IFN and RANTES expression. These data suggest that virus proliferation rates and the immune response profile are different in nasal epithelial cells from patients with allergic rhinitis compared to healthy individuals.

Keywords: allergic rhinitis; interferons; parainfluenza type 3 virus; primary nasal epithelial cells; rhinovirus 1B.

Figure 1

Virus copy number in nasal epithelial cells (NECs) from patients with allergic rhinitis (AR) and healthy controls (HC). (a) Parainfluenza virus type 3 (PIV3) gene copy number relative to known standards (AR: n = 6; HC: n = 5). (b) Rhinovirus 1B (RV1B) gene copy number relative to known standards (AR: n = 5; HC: n = 7 unless noted otherwise). Data presented as mean (± standard deviation). Statistical differences between AR and HC are denoted as *P < 0·05 or **P < 0·01; ^##statistical differences between 8 and 48 h post‐infection in HC (P < 0·01); ^&statistical difference between 8 and 48 h post‐infection in AR (P < 0·05).

Figure 2

Cell cytotoxicity upon viral infections in nasal epithelial cells (NECs) from patients with allergic rhinitis (AR) and healthy controls (HC). (a) Parainfluenza virus type 3 (PIV3)‐induced cytotoxicity in nasal epithelial cells (AR: n = 5; HC: n = 8 unless noted otherwise). (b) Rhinovirus 1B (RV1B)‐induced cytotoxicity in nasal epithelial cells (AR: n = 7; HC: n = 9 unless noted otherwise). Data presented as mean (± standard deviation).

Figure 3

Virus‐induced type III interferon (IFN‐λ1) generation in nasal epithelial cells (NECs) from allergic rhinitis (AR) and healthy controls (HC). (a) Parainfluenza virus type 3 (PIV3)‐induced IFN‐λ1 protein release at 48h (AR: n = 7; HC: n = 9). (b) Rhinovirus 1B (RV1B)‐induced IFN‐λ1 protein release at 48h (AR: n = 7; HC: n = 7). (c) PIV3‐induced IFN‐λ1 gene expression (AR: n = 7; HC: n = 7). (d) RV1B‐induced IFN‐λ1 gene expression (AR: n = 7; HC: n = 8 unless noted otherwise). Data presented as mean (± standard deviation). Statistical difference between AR and HC is denoted as *P < 0·05; ^&&significant difference between 8 and 48 h in AR (P < 0·01).

Figure 4

Virus‐induced type I interferon (IFN‐β) generation in nasal epithelial cells (NECs) from allergic rhinitis (AR) and healthy controls (HC). (a) Parainfluenza virus type 3 (PIV3)‐induced IFN‐β gene expression (AR: n = 7; HC: n = 7). (b) Rhinovirus 1B (RV1B)‐induced IFN‐β gene expression (AR: n = 7; HC: n = 8 unless noted otherwise). Data presented as mean (± standard deviation). #Significant difference between 8 and 48 h in HC (P < 0·05); ^&&significant difference between 8 and 48 h AR (P < 0·01).

Figure 5

Virus‐induced regulated on activation, normal T expressed and secreted (RANTES) generation in nasal epithelial cells (NECs) from allergic rhinitis (AR) and healthy controls (HC). (a) Parainfluenza virus type 3 (PIV3)‐induced RANTES protein release at 48 h (AR: n = 7; HC: n = 8). (b) RV1B‐induced RANTES protein release at 48 h (AR: n = 7; HC: n = 8). (c) PIV3‐induced RANTES gene expression (AR: n = 7; HC: n = 7). (d) RV1B‐induced RANTES gene expression (AR: n = 7; HC: n = 8 unless noted otherwise). Data presented as mean (± standard deviation). Statistical difference between AR and HC is denoted as *P < 0·05. Significant difference between 8 and 48 h in HC are denoted as ^# P < 0·05 or ^### P < 0·001.

Figure 6

Virus‐induced interferon regulatory factor (IRF)7 and IRF3 gene expression in nasal epithelial cells (NECs) from allergic rhinitis (AR) and healthy controls (HC). (a) Parainfluenza virus type 3 (PIV3)‐induced IRF7 gene expression (AR: n = 7; HC: n = 7). (b) Rhinovirus 1B (RV1B)‐induced IRF7 gene expression (AR: n = 7; HC: n = 8 unless noted otherwise). (c) PIV3‐induced IRF3 gene expression (AR: n = 7; HC: n = 7). (d) RV1B‐induced IRF3 gene expression (AR: n = 7; HC: n = 8 unless noted otherwise. Data presented as mean (± standard deviation). ^&&&Statistical difference between 8 and 48 h post‐infection in AR (P < 0·001); ^#significant differences between 8 and 48 h in HC (P < 0·05).

Figure 7

Poly (I:C)‐induced interferon (IFN)‐λ1, IFN‐β and regulated on activation, normal T expressed and secreted (RANTES) generation in nasal epithelial cells (NECs) from allergic rhinitis (AR) and healthy controls (HC). (a) IFN‐λ1 protein release (AR: n = 8; HC: n = 8). (b) IFN‐λ1 gene expression (AR: n = 7; HC: n = 7). (c) IFN‐β gene expression (AR: n = 7; HC: n = 7). (d) RANTES protein release (AR: n = 8; HC: n = 8). (e) RANTES gene expression (AR: n = 7; HC: n = 7). Data presented as mean (± standard deviation). ^#Significant difference between 8 and 24 h in HC when P < 0·05, ^## P < 0·01 or ^### P < 0·001; ^&&significant difference between 8 and 24 h in AR (P < 0·01).