key: cord-0819880-ycw4ezzk authors: Wang, Hai; Song, Jia; Yao, Yin; Deng, Yi‐; Wang, Zhi‐Chao; Liao, Bo; Ma, Jin; He, Chao; Pan, Li; Liu, Yang; Xie, Jun‐ang; Zeng, Ming; Liu, Zheng title: ACE2 expression and its implication in the association between COVID‐19 and allergic rhinitis date: 2020-08-27 journal: Allergy DOI: 10.1111/all.14569 sha: a215e98969b3252e2ce35f4d60f830ad735ea887 doc_id: 819880 cord_uid: ycw4ezzk nan Summary: AR comorbidity is not associated with severe illness of COVID-19. ACE2 expression in nasal tissues is not altered in AR. ACE2 expression in airway epithelial cells seems to be regulated, at least in part, by the counter effect of IFN and type 2 inflammation. Coronavirus disease 2019 (COVID-19), caused by severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2), affects more than 17 million of people and results in more than 666,000 deaths all over the world. Although allergic diseases are highly prevalent globally, their risks for the development of COVID-19 remain poorly understood. SARS-CoV-2 entry host cells via angiotensin-converting enzyme II (ACE2). 1 Upregulated ACE2 expression has been associated with increased risk of COVID-19 in patients with chronic obstructive pulmonary disease, diabetes, and hypertension. 2 ACE2 gene expression is enriched in nasal epithelial cells, highlighting the importance of nose as a portal for initial SARS-CoV-2 infection and transmission. This article is protected by copyright. All rights reserved Allergic rhinitis (AR) is the most common disorder of nose and affects 10% to 40% of the population. 3 Previous studies reported low incidences of AR in COVID-19 patients, ranging from 0% to 1.8% in China. 4, 5 However, those results were generated solely based on the medical records, and AR comorbidity might not be well considered under actual emergency situation. 4, 5 Moreover, the association between AR comorbidity and the disease severity of COVID-19 and the role of ACE2 in this association are largely unknown. Here we retrospectively analyzed 1,172 etiologically confirmed COVID-19 patients discharged from Tongji Hospital, Wuhan, China from January 27, 2020 to March 10, 2020. Hospital electronic medical records were extracted and comorbidities were reevaluated by the telephone follow-up. Both multivariate logistic regression and propensity score matching (PSM) analysis were performed to exclude the influence of potential confounding variables. In addition, repository inferior turbinate tissues and cells from 29 control subjects without AR and 29 patients with AR undergoing nasal septoplasty and collected before COVID-19 era were used for the study of ACE2 expression. Human nasal epithelial cells (HNECs) were collected by epithelial scrapings of the inferior turbinates from subjects without AR. Primary HNECs were cultured with the air-liquid interface method. The cell culture was also performed before COVID-19 era, and the ACE2 expression was analyzed in this study. The RNA-seq data of nasal and bronchial brushings from 7 patients with concomitant AR and asthma and 9 healthy controls were acquired from the Gene Expression Omnibus database (GSE101720). More information regarding subjects and methods is provided in this article's Online Supplement including Table S1-S2. In our cohort, 115 (9.8%) patients reported physician-diagnosed AR. COVID-19 patients without AR were older than those with AR (61 [49-69] vs. 54 [40 -65]; P < 0.01). Patients with AR had a higher incidence of concomitant chronic liver disease (4.4% vs. 1.1%; P = 0.02), and tended to have a higher incidence of asthma comorbidity (5.2% vs. 2.2%; P = 0.06) and a lower incidence of hypertension (24.4% vs. 32.5%; P = 0.07) than those without AR (Table S3 ). After adjusting for or propensity score matching for confounding factors, including age, gender, smoking status, and comorbidities (Table S3 ), no significant difference in frequencies of symptoms or laboratory results was found between COVID-19 patients with and without AR This article is protected by copyright. All rights reserved (Table 1 and Table S4 ). Importantly, no difference in the frequencies of severe cases on admission, receiving mechanical ventilation and other treatments, or complications including severe acute respiratory syndrome was revealed for patients with and without AR either (Table 1) . In PSM analysis, we were able to match 109 patients without AR to 109 patients with AR at a ratio of 1:1 (Table S3) . We next studied ACE2 expression and found its mRNA and protein expression in nasal tissues was comparable between AR patients and control subjects (Fig 1, A and B ). ACE2 mRNA expression was downregulated by IL-4 and IL-13, whereas upregulated by IFN-α, IFN-γ, and TNF-α in cultured HNECs (Fig 1, C) . We discovered that the mRNA expression of type 2 response genes, including ST6GAL1, POSTN and CCL26, was increased in nasal tissues in AR patients compared with that in non-AR controls, however, the mRNA expression of IFN response genes, including CXCL10 and CXCL11, was comparable between AR patients and non-AR controls ( Fig S1) . ACE2 expression positively correlated with the expression of IFN response genes, but not type 2 response genes, in nasal tissues when analyzing AR and control subjects together or separately ( In contrast to nasal epithelial cells, ACE2 gene expression was decreased in bronchial epithelial cells in patients with concomitant AR and allergic asthma as compared to that in healthy controls by analyzing GSE101720 datasheet (Fig S5, A) . ACE2 gene expression negatively correlated with the expression of type 2 response genes (POSTN, CLCA1 and IL1RL1), but not IFN response genes (IFI6, CXCL10 and CXCL11) in bronchial epithelial cells when analyzing all the subjects or patients with asthma and AR alone (Fig S5, B and Fig S6) . We further found nasal epithelial cells had higher ACE2 and CXCL10 expression levels, but lower POSTN, CLCA1, CPA3 and IL1RL1 expression compared with those in bronchial epithelial cells (Fig S7, A) in patients with concomitant AR and asthma. Consistently, the gene expression ratios of CXCL10/ST6GAL1, CXCL10/POSTN, CXCL10/CPA3, and CXCL10/IL1RL1 were higher in nasal epithelial cells than This article is protected by copyright. All rights reserved in bronchial epithelial cells (Fig S7, B) , suggesting a predominant IFN and type 2 response in upper and lower airways, respectively, under allergic condition. In this study, we carefully confirmed and reevaluated AR comorbidity in discharged COVID-19 patients by telephone follow-up. This may be the reason that the AR prevalence in our cohort (9.8%) was higher than those previously reported in Chinese COVID-19 patients (0%-1.8%). 4, 5 The prevalence of AR in our COVID-19 cohort is comparable to that in general populations in Wuhan (9.7%). 6 In addition, we didn't find any association between AR comorbidity and disease severity in COVID-19 patients. Chhiba KD et al. have recently reported that AR was not associated with an increased risk of COVID-19-related hospitalization. 7 Collectively, these results indicate that primary AR may not modify the risk for COVID-19. In line with recent reports, 8, 9 we found that type 2 cytokines downregulated, whereas IFNs upregulated ACE2 gene expression in HNECs. However, ACE2 expression correlated with IFN response, but not type 2 response, in nasal tissues and epithelial cells, underscoring a predominant role of IFNs in regulating ACE2 expression in upper airways. 9 AR and allergic asthma are frequently co-occurred and may share common immune-pathogenic mechanisms such as type 2 inflammation. However, we found that patients with concomitant AR and allergic asthma had reduced ACE2 expression in bronchial epithelial cells, which is likely regulated by type 2 response. The difference in ACE2 expression in allergic nasal and bronchial epithelial cells is possibly related to the different tension of IFN and type 2 response in upper and lower airways under allergic condition. Therefore, the counter effect of IFN and type 2 response may have an important role in regulating ACE2 expression in airways. The reduced ACE2 expression in allergic asthmatics may suggest a lower risk for COVID-19. Low prevalence of asthma (0-0.9%) were observed in patients with COVID-19 in several studies in China. 4 In a USA cohort, Chhiba et al. recorded a relatively high prevalence of asthma (14%); however, there was no significant difference in hospitalization rate or mortality between patients with and without asthma. 7 Our study has several limitations. First, self-reported symptoms and comorbidities might lead to the potential misestimation of the prevalence and the strength of association with the clinical This article is protected by copyright. All rights reserved outcomes. Second, we did not include fatal cases since no subsequent follow-up confirmation of comorbidities could be made for them. Third, we could not get the demographic information of subjects in the public gene dataset, and the number of subjects was limited. We therefore could not preclude the potential bias. However, the nasal epithelial cell results were consistent with our nasal tissue results derived from a relatively larger cohort. In conclusion, for the first time, we provide the evidence that AR comorbidity may not have significant modifying effect on the development and expression of COVID-19. ACE2 expression is not altered in AR patients. ACE2 gene expression in airways is regulated, at least in part, by the counter effect of type 2 and IFN inflammation. The authors declare that they have no conflicts of interest. This article is protected by copyright. All rights reserved Functional assessment of cell entry and receptor usage for SARS-CoV-2 and other lineage B betacoronaviruses Physiological and pathological regulation of ACE2, the SARS-CoV-2 receptor Allergic diseases and asthma: a global public health concern and a call to action Clinical characteristics of 140 patients infected with SARS-CoV-2 in Wuhan Perspective: COVID-19, Implications of nasal diseases and consequences for their management An increased prevalence of self-reported allergic rhinitis in major Chinese cities from Prevalence and characterization of asthma in hospitalized and non-hospitalized patients with COVID-19 Type 2 inflammation modulates ACE2 and TMPRSS2 in airway epithelial cells SARS-CoV-2 Receptor ACE2 Is an Interferon-Stimulated Gene in Human Airway Epithelial Cells and Is Detected in Specific Cell Subsets across Tissues This article is protected by copyright. All rights reserved Accepted Article