Interferons and other cytokines, genetics and beyond in COVID-19 and autoimmunity.

Interferons are the best antiviral agents in vitro against SARS-CoV-2 so far and genetic defects in their signaling cascade or neutralization of alfa-interferons by autoantibodies come with more severe COVID-19. However, there is more, as the SARS-CoV-2 dysregulates not only innate immune mechanisms but also T and B cell repertoires. Most genetic, hematological and immunological studies in COVID-19 are at present phenomenological. However, these and antecedent studies contain the seed grains to resolve many unanswered questions and a whole range of testable hypotheses. What are the links, if existing, between genetics and the occurrence of interferon-neutralizing antibodies? Are NAGGED (neutralizing and generated by gene defect) antibodies involved or not? Is the autoimmune process cause or consequence of virus infection? What are the roles played by cytokine posttranslational modifications, such as proteolysis, glycosylation, citrullination and others? How is systemic autoimmunity linked with type 1 interferons? These questions place cytokines and growth factors at pole positions as keys to unlock basic mechanisms of infection and (auto)immunity. Related to cytokine research, (1) COVID-19 patients develop neutralizing autoantibodies, mainly against alpha interferons and it is not yet established whether this is the consequence or cause of virus replication. (2) The glycosylation of recombinant interferon-beta protects against breaking tolerance and the development of neutralizing antibodies. (3) SARS-CoV-2 induces severe inflammation and release of extracellular proteases leading to remnant epitopes, e.g. of cytokines. (4) In the rare event of homozygous cytokine gene segment deletions, observed neutralizing antibodies may be named NAGGED antibodies. (5) Severe cytolysis releases intracellular content into the extracellular milieu and leads to regulated degradation of intracellular proteins and selection of antibody repertoires, similar to those observed in patients with systemic lupus erythematosus. (6) Systematic studies of novel autoimmune diseases on single cytokines will complement the present picture about interferons. (7) Interferon neutralization in COVID-19 constitutes a preamble of more studies about cytokine-regulated proteolysis in the control of autoimmunity. Here we reformulate these seven conjectures into testable questions for future research.

Type I and III IFN-mediated antiviral actions counteracted by SARS-CoV-2 proteins and host inherited factors.

SARS-CoV-2 is a recently identified coronavirus accountable for the current pandemic disease known as COVID-19. Different patterns of disease progression infer a diverse host immune response, with interferon (IFN) being pivotal. IFN-I and III are produced and released by virus-infected cells during the interplay with SARS-CoV-2, thus establishing an antiviral state in target cells. However, the efficacy of IFN and its role in the possible outcomes of the disease are not yet defined, as it is influenced both by factors inherent to the virus and to the host. The virus exhibits multiple strategies to counteract the innate immune response, including those shared by SARS-CoV and MERS-CoV and other novel ones. Inborn errors in the host may affect IFN-related effector proteins or decrease its levels in plasma upon neutralization by preexistent autoantibodies. This battle between the IFN response triggered upon SARS-CoV-2 infection, its magnitude and timing, and the efficacy of its antiviral tools in dispute against the viral evasion strategies together with the genetic factors of the host, generate a scenario whose fate contributes to defining the severity of COVID-19.

Impact of Coronavirus Disease 2019 (COVID-19) on Patients With Congenital Heart Disease Across the Lifespan: The Experience of an Academic Congenital Heart Disease Center in New York City.

Background We sought to assess the impact and predictors of coronavirus disease 2019 (COVID-19) infection and severity in a cohort of patients with congenital heart disease (CHD) at a large CHD center in New York City. Methods and Results We performed a retrospective review of all individuals with CHD followed at Columbia University Irving Medical Center who were diagnosed with COVID-19 between March 1, 2020 and July 1, 2020. The primary end point was moderate/severe response to COVID-19 infection defined as (1) death during COVID-19 infection; or (2) need for hospitalization and/or respiratory support secondary to COVID-19 infection. Among 53 COVID-19-positive patients with CHD, 10 (19%) were <18 years of age (median age 34 years of age). Thirty-one (58%) had complex congenital anatomy including 10 (19%) with a Fontan repair. Eight (15%) had a genetic syndrome, 6 (11%) had pulmonary hypertension, and 9 (17%) were obese. Among adults, 18 (41%) were physiologic class C or D. For the entire cohort, 9 (17%) had a moderate/severe infection, including 3 deaths (6%). After correcting for multiple comparisons, the presence of a genetic syndrome (odds ratio [OR], 35.82; P=0.0002), and in adults, physiological Stage C or D (OR, 19.38; P=0.002) were significantly associated with moderate/severe infection. Conclusions At our CHD center, the number of symptomatic patients with COVID-19 was relatively low. Patients with CHD with a genetic syndrome and adults at advanced physiological stage were at highest risk for moderate/severe infection.

Recommended measures for the efficient care of patients with genetic disorders during the COVID-19 pandemic in low and middle income countries.

The coronavirus disease 2019 (COVID-19) emerged in early 2020 and since, has brought about tremendous cost to economies and healthcare systems universally. Reports of pediatric patients with inherited conditions and COVID-19 infections are emerging. Specific risks for morbidity and mortality that this pandemic carries for different categories of genetic disorders are still mostly unknown. Thus, there are no specific recommendations for the diagnosis, management, and treatment of patients with genetic disorders during the COVID-19 or other pandemics. Emerging publications, from Upper-Middle Income countries (UMIC), discuss the recent experiences of genetic centers in the continuity of care for patients with genetic disorders in the context of this pandemic. Many measures to facilitate the plan to continuous genetic care in a well-developed health system, may not be applicable in Low and Middle Income countries (LMIC). With poorly structured health systems and with the lack of established genetic services, the COVID-19 pandemic will easily exacerbate the access to care for patients with genetic disease in these countries. This article focuses on the unique challenges of providing genetic healthcare services during emergency situations in LMIC countries and provides practical preparations for this and other pandemic situations.