Prevalence of Neutralizing Autoantibodies Against Type I Interferon in a Multicenter Cohort of Severe or Critical COVID-19 Cases in Shanghai

OBJECTIVE

We sought to explore the prevalence of type I interferon-neutralizing antibodies in a Chinese cohort and its clinical implications during the Omicron variant wave of SARS-CoV-2.

METHODS

Type I interferon (IFN) autoantibodies possessing neutralizing capabilities were identified using luciferase assays. The capacity of the autoantibodies for in vitro interference with antiviral activity of IFN was assessed by using a SARS-CoV-2 replicon system. An analysis of the demographic and clinical profiles of patients exhibiting neutralizing antibodies was also conducted.

RESULTS

In this cohort, 11.8% of severe/critical cases exhibited the existence of type I IFN-neutralizing antibodies, specifically targeting IFN-α2, IFN-ω, or both, with an elderly male patient tendency. Notably, these antibodies exerted a pronounced inhibitory effect on the antiviral activity of IFN against SARS-CoV-2 under controlled in vitro conditions. Furthermore, a noteworthy correlation was discerned between the presence of these neutralizing antibodies and critical clinical parameters, including C-reactive protein (CRP) levels, D-dimer levels, and lymphocyte counts.

CONCLUSION

The presence of type I IFN-neutralizing antibodies is a pervasive risk factor for severe/critical COVID-19 in the Chinese population.

Correlation Between MicroRNA by Extracellular Vesicle Mediated and Antiviral Effects of Interferon Omega in Feline Peripheral Blood

Feline interferon omega (IFN-ω) has been proven to have high antiviral activity; however, its in-depth antiviral effects remain unknown. Extracellular vesicles (EVs) have been demonstrated to participate in the regulation of the immune response pathway for the body through various active substances, especially through the microRNA (miRNA) carried by them. In this study, we isolated EVs from feline peripheral blood by differential centrifugation, and further found that the content of IFN-ω in EVs increased continuously within 24 h after IFN-ω treatment, and a large number of miRNAs were significantly downregulated in EVs within 12 h after IFN-ω treatment. These significantly differentially expressed miRNAs were important for regulating changes in antiviral cytokines. This study reveals for the first time the correlation between EVs-mediated miRNA in feline peripheral blood and IFN-ω on antiviral immune response, which may provide strong data support for the development of novel antiviral nanomedicine and the research of the antiviral effects of IFN-ω.

Neutralizing Type I Interferon Autoantibodies in Japanese Patients with Severe COVID-19

Purpose

Autoantibodies (aAbs) to type I interferons (IFNs) have been found in less than 1% of individuals under the age of 60 in the general population, with the prevalence increasing among those over 65. Neutralizing autoantibodies (naAbs) to type I IFNs have been found in at least 15% of patients with life-threatening COVID-19 pneumonia in several cohorts of primarily European descent. We aimed to evaluate the prevalence of aAbs and naAbs to IFN-α2 or IFN-ω in Japanese patients who suffered from COVID-19 as well as in the general population.

Methods

Patients who suffered from COVID-19 (n = 622, aged 0–104) and an uninfected healthy control population (n = 3,456, aged 20–91) were enrolled in this study. The severities of the COVID-19 patients were as follows: critical (n = 170), severe (n = 235), moderate (n = 112), and mild (n = 105). ELISA and ISRE reporter assays were used to detect aAbs and naAbs to IFN-α2 and IFN-ω using E. coli-produced IFNs.

Results

In an uninfected general Japanese population aged 20–91, aAbs to IFNs were detected in 0.087% of individuals. By contrast, naAbs to type I IFNs (IFN-α2 and/or IFN-ω, 100 pg/mL) were detected in 10.6% of patients with critical infections, 2.6% of patients with severe infections, and 1% of patients with mild infections. The presence of naAbs to IFNs was significantly associated with critical disease (P = 0.0012), age over 50 (P = 0.0002), and male sex (P = 0.137). A significant but not strong correlation between aAbs and naAbs to IFN-α2 existed (r =  − 0.307, p value < 0.0001) reinforced the importance of measuring naAbs in COVID-19 patients, including those of Japanese ancestry.

Conclusion

In this study, we revealed that patients with pre-existing naAbs have a much higher risk of life-threatening COVID-19 pneumonia in Japanese population.

Supplementary Information

The online version contains supplementary material available at 10.1007/s10875-022-01308-3.

Temporal Dynamics of Anti-Type 1 Interferon Autoantibodies in Patients With Coronavirus Disease 2019

Binding levels and neutralization activity of anti-type 1 interferon autoantibodies peaked during acute coronavirus disease 2019 and markedly decreased thereafter. Most patients maintained some ability to neutralize type 1 interferon into convalescence despite lower levels of binding immunoglobulin G. Identifying these autoantibodies in healthy individuals before the development of critical viral disease may be challenging.

Interferon therapies in small animals

Interferons (IFNs) are cytokines that play an important role in the immune response of animals and humans. A number of studies reviewed here have evaluated the use of human, canine and feline IFNs as treatments for infectious, inflammatory and neoplastic disease in dogs and cats. Recombinant canine IFN-γ is deemed an efficacious therapy for canine atopic dermatitis. Recombinant feline IFN-ω is effective against canine parvoviral enteritis and has also been recommended for canine atopic dermatitis. Based on limited evidence, recombinant canine IFN-α could be a topical treatment option for dogs with gingivitis and keratoconjunctivitis sicca. Conclusive evidence is lacking for other diseases and large randomised controlled trials are needed before IFNs can be recommended for other indications.

Use of IFN-Based Biotherapeutics to Harness the Host Against Foot-And-Mouth Disease

Foot-and-mouth disease (FMD) is a highly contagious vesicular disease of cloven-hoofed animals that severely constrains international trade of livestock and animal products. Currently, disease control measures include broad surveillance, enforcement of sanitary policy, and use of an inactivated vaccine. While use of these measures has contributed to eliminating foot-and-mouth disease virus (FMDV) from a vast area of the world, the disease remains endemic in three continents, and outbreaks occasionally appear in previously declared FMD-free zones, causing economic and social devastation. Among others, a very fast rate of viral replication and the need for 7 days to achieve vaccine-induced protection are the main limitations in controlling the disease. New fast-acting antiviral strategies targeted to boost the innate immunity of the host to block viral replication are needed. Here we review the knowledge on the multiple strategies FMDV has evolved to block the host innate immunity, with particularly focus on the past and current research toward the development of interferon (IFN)-based biotherapeutics in relevant livestock species.