ABSTRACT
Inborn errors of immunity (IEI) are a diverse and growing category of more than 430 chronic disorders that share susceptibilities to infections. Whether the result of a genetic lesion that causes defective granule-dependent cytotoxicity, excessive lymphoproliferation, or an overwhelming infection represents a unique antigenic challenge, IEIs can display a proclivity for cytokine storm syndrome (CSS) development. This chapter provides an overview of CSS pathophysiology as it relates to IEIs. For each IEI, the immunologic defect and how it promotes or discourages CSS phenomena are reviewed. The IEI-associated molecular defects in pathways that are postulated to be critical to CSS physiology (i.e., toll-like receptors, T regulatory cells, the IL-12/IFNγ axis, IL-6) and, whenever possible, review strategies for treating CSS in IEI patients with molecularly directed therapies are highlighted.
Subject(s)
Cytokine Release Syndrome , Humans , Cytokine Release Syndrome/immunology , Cytokines/immunology , Cytokines/metabolism , Animals , Genetic Diseases, Inborn/immunology , Genetic Diseases, Inborn/genetics , Genetic Diseases, Inborn/pathologyABSTRACT
More than 450 genetic defects result in inborn errors of immunity (IEI). Their individual prevalence in specific cohorts is influenced by national characteristics and other factors. We present results of genetic testing conducted in 1809 Russian children with IEI. Genetic defects confirming IEI were found in 1112 out of 1809 (61.5%) probands. These defects included variants in 118 single genes (87.9% of patients) and aberrations in 6 chromosomes (11.8%). Notably, three patients harbored pathogenic variants in more than one IEI gene. Large deletions constituted 5% of all defects. Out of the 799 original variants, 350 (44%) have not been described previously. Rare genetic defects (10 or fewer patients per gene) were identified in 20% of the patients. Among 967 probands with germline variants, defects were inherited in an autosomal dominant manner in 29%, X-linked in 34%, and autosomal recessive in 37%. Four females with non-random X-inactivation exhibited symptoms of X-linked diseases (BTK, WAS, CYBB, IKBKG gene defects). Despite a relatively low rate of consanguinity in Russia, 47.9% of autosomal recessive gene defects were found in a homozygous state. Notably, 28% of these cases carried "Slavic" mutation of the NBN gene or known hot-spot mutations in other genes. The diversity of IEI genetic forms and the high frequency of newly described variants underscore the genetic heterogeneity within the Russian IEI group. The new variants identified in this extensive cohort will enrich genetic databases.
Subject(s)
Genetic Testing , Humans , Female , Male , Child , Child, Preschool , Infant , Cohort Studies , Russia/epidemiology , Adolescent , Mutation/genetics , Infant, Newborn , Genetic Diseases, Inborn/genetics , Genetic Diseases, Inborn/immunology , Genetic Diseases, Inborn/epidemiology , Immune System Diseases/genetics , Immune System Diseases/diagnosis , Genetic Predisposition to DiseaseABSTRACT
Four in five children with inborn errors of immunity globally remain undiagnosed. These figures are disproportionally high in low-income countries like Ethiopia. Apart from the inclusion of basic overviews of these disorders in to postgraduate pediatric curricula, little effort has been placed in to establishing clinical immunology training programs. This report summarizes the existing epidemiology of inborn errors of immunity in Ethiopia, unique presentations in Ethiopian children, challenges faced in diagnosing them, and efforts to improve their management.
Subject(s)
Genetic Diseases, Inborn , Immune System Diseases , Child , Humans , Ethiopia/epidemiology , Genetic Diseases, Inborn/epidemiology , Genetic Diseases, Inborn/immunology , Immune System Diseases/epidemiology , Immune System Diseases/geneticsABSTRACT
BACKGROUND: Patients with inborn errors of immunity (IEI) are at increased risk of severe coronavirus disease-2019 (COVID-19). Effective vaccination against COVID-19 is therefore of great importance in this group, but little is known about the immunogenicity of COVID-19 vaccines in these patients. OBJECTIVES: We sought to study humoral and cellular immune responses after mRNA-1273 COVID-19 vaccination in adult patients with IEI. METHODS: In a prospective, controlled, multicenter study, 505 patients with IEI (common variable immunodeficiency [CVID], isolated or undefined antibody deficiencies, X-linked agammaglobulinemia, combined B- and T-cell immunodeficiency, phagocyte defects) and 192 controls were included. All participants received 2 doses of the mRNA-1273 COVID-19 vaccine. Levels of severe acute respiratory syndrome coronavirus-2-specific binding antibodies, neutralizing antibodies, and T-cell responses were assessed at baseline, 28 days after first vaccination, and 28 days after second vaccination. RESULTS: Seroconversion rates in patients with clinically mild antibody deficiencies and phagocyte defects were similar to those in healthy controls, but seroconversion rates in patients with more severe IEI, such as CVID and combined B- and T-cell immunodeficiency, were lower. Binding antibody titers correlated well to the presence of neutralizing antibodies. T-cell responses were comparable to those in controls in all IEI cohorts, with the exception of patients with CVID. The presence of noninfectious complications and the use of immunosuppressive drugs in patients with CVID were negatively correlated with the antibody response. CONCLUSIONS: COVID-19 vaccination with mRNA-1273 was immunogenic in mild antibody deficiencies and phagocyte defects and in most patients with combined B- and T-cell immunodeficiency and CVID. Lowest response was detected in patients with X-linked agammaglobulinemia and in patients with CVID with noninfectious complications. The assessment of longevity of immune responses in these vulnerable patient groups will guide decision making for additional vaccinations.
Subject(s)
2019-nCoV Vaccine mRNA-1273 , Antibodies, Neutralizing , COVID-19 , Genetic Diseases, Inborn , Immunologic Deficiency Syndromes , 2019-nCoV Vaccine mRNA-1273/blood , 2019-nCoV Vaccine mRNA-1273/immunology , 2019-nCoV Vaccine mRNA-1273/therapeutic use , Adult , Agammaglobulinemia/genetics , Agammaglobulinemia/immunology , Antibodies, Neutralizing/blood , Antibodies, Neutralizing/immunology , Antibodies, Viral/blood , Antibodies, Viral/genetics , Antibodies, Viral/immunology , COVID-19/immunology , COVID-19/prevention & control , COVID-19 Vaccines/immunology , COVID-19 Vaccines/therapeutic use , Common Variable Immunodeficiency/genetics , Common Variable Immunodeficiency/immunology , Genetic Diseases, Inborn/blood , Genetic Diseases, Inborn/genetics , Genetic Diseases, Inborn/immunology , Genetic Diseases, X-Linked/genetics , Genetic Diseases, X-Linked/immunology , Humans , Immunologic Deficiency Syndromes/blood , Immunologic Deficiency Syndromes/genetics , Immunologic Deficiency Syndromes/immunology , Primary Immunodeficiency Diseases/genetics , Primary Immunodeficiency Diseases/immunology , Prospective Studies , SARS-CoV-2 , Spike Glycoprotein, CoronavirusABSTRACT
In the last 10 years there has been enormous progress in the field of inborn errors of immunity (IEI). The number of newly discovered diseases is growing exponentially, including not only rare but also frequent genetic defects. The spectrum of clinical phenotypes ascribed to IEI is also rapidly expanding. There is every reason to assume that this is only the tip of the iceberg and in the near future further IEI will be discovered with the help of genetic and immunological studies. Patients will benefit from the timely diagnostics as well as from the individualized treatment.
Subject(s)
Genetic Diseases, Inborn , Genetic Diseases, Inborn/immunology , HumansABSTRACT
Disease and accompanying inflammation are uncommon outcomes of viral infection in humans. Clinical inflammation occurs if steady-state cell-intrinsic and leukocytic immunity to viruses fails. Inflammation attests to the attempts of newly recruited and activated leukocytes to resolve infection in the blood or tissues. In the confusing battle between a myriad of viruses and cells, studies of human genetics can separate the root cause of inflammation and disease from its consequences. Single-gene inborn errors of cell-intrinsic or leukocytic immunity underlying diverse infections in the skin, brain, or lungs can help to clarify the human determinants of viral disease. The genetic elucidation of immunological deficits in a single patient with a specific vulnerability profile can reveal mechanisms of inflammation and disease that may be triggered by other causes, inherited or otherwise, in other patients. This human genetic dissection of viral infections is giving rise to a new biology and a new medicine.
Subject(s)
Genetic Diseases, Inborn/immunology , Immunity/genetics , Inflammation/genetics , Inflammation/immunology , Virus Diseases/genetics , Virus Diseases/immunology , Autoimmunity/genetics , Genetic Predisposition to Disease , Humans , Interferon Type I/immunologyABSTRACT
After decades of extensive fundamental studies and clinical trials, lipid nanoparticles (LNPs) have demonstrated effective mRNA delivery such as the Moderna and Pfizer-BioNTech vaccines fighting against COVID-19. Moreover, researchers and clinicians have been investigating mRNA therapeutics for a variety of therapeutic indications including protein replacement therapy, genome editing, and cancer immunotherapy. To realize these therapeutics in the clinic, there are many formidable challenges. First, novel delivery systems such as LNPs with high delivery efficiency and low toxicity need to be developed for different cell types. Second, mRNA molecules need to be engineered for improved pharmaceutical properties. Lastly, the LNP-mRNA nanoparticle formulations need to match their therapeutic applications.In this Account, we summarize our recent advances in the design and development of various classes of lipids and lipid derivatives, which can be formulated with multiple types of mRNA molecules to treat diverse diseases. For example, we conceived a series of ionizable lipid-like molecules based on the structures of a benzene core, an amide linker, and hydrophobic tails. We identified N1,N3,N5-tris(3-(didodecylamino)propyl)benzene-1,3,5-tricarboxamide (TT3) as a lead compound for mRNA delivery both in vitro and in vivo. Moreover, we tuned the biodegradability of these lipid-like molecules by introducing branched ester or linear ester chains. Meanwhile, inspired by biomimetic compounds, we synthesized vitamin-derived lipids, chemotherapeutic conjugated lipids, phospholipids, and glycolipids. These scaffolds greatly broaden the chemical space of ionizable lipids for mRNA delivery. In another section, we highlight our efforts on the research direction of mRNA engineering. We previously optimized mRNA chemistry using chemically-modified nucleotides to increase the protein expression, such as pseudouridine (ψ), 5-methoxyuridine (5moU), and N1-methylpseudouridine (me1ψ). Also, we engineered the sequences of mRNA 5' untranslated regions (5'-UTRs) and 3' untranslated regions (3'-UTRs), which dramatically enhanced protein expression. With the progress of LNP development and mRNA engineering, we consolidate these technologies and apply them to treat diseases such as genetic disorders, infectious diseases, and cancers. For instance, TT3 and its analog-derived lipid-like nanoparticles can effectively deliver factor IX or VIII mRNA and recover the clotting activity in hemophilia mouse models. Engineered mRNAs encoding SARS-CoV-2 antigens serve well as vaccine candidates against COVID-19. Vitamin-derived lipid nanoparticles loaded with antimicrobial peptide-cathepsin B mRNA enable adoptive macrophage transfer to treat multidrug resistant bacterial sepsis. Biomimetic lipids such as phospholipids formulated with mRNAs encoding costimulatory receptors lead to enhanced cancer immunotherapy.Overall, lipid-mRNA nanoparticle formulations have considerably benefited public health in the COVID-19 pandemic. To expand their applications in clinical use, research work from many disciplines such as chemistry, engineering, materials, pharmaceutical sciences, and medicine need to be integrated. With these collaborative efforts, we believe that more and more lipid-mRNA nanoparticle formulations will enter the clinic in the near future and benefit human health.
Subject(s)
Drug Carriers/chemistry , Liposomes/chemistry , Nanoparticles/chemistry , RNA, Messenger/chemistry , Animals , Benzamides/chemistry , Biomimetic Materials/chemistry , Communicable Diseases/immunology , Communicable Diseases/therapy , Disease Models, Animal , Genetic Diseases, Inborn/immunology , Genetic Diseases, Inborn/therapy , Humans , Mice , Neoplasms/immunology , Neoplasms/therapy , Phospholipids/chemistry , RNA, Messenger/metabolism , RNA, Messenger/therapeutic use , Untranslated Regions , Vitamins/chemistryABSTRACT
Since its discovery, the Janus kinase-signal transduction and activation of transcription (JAK-STAT) pathway has become recognized as a central mediator of widespread and varied human physiological processes. The field of JAK-STAT biology, particularly its clinical relevance, continues to be shaped by 2 important advances. First, the increased use of genomic sequencing has led to the discovery of novel clinical syndromes caused by mutations in JAK and STAT genes. This has provided insights regarding the consequences of aberrant JAK-STAT signaling for immunity, lymphoproliferation, and malignancy. In addition, since the approval of ruxolitinib and tofacitinib, the therapeutic use of JAK inhibitors (jakinibs) has expanded to include a large spectrum of diseases. Efficacy and safety data from over a decade of clinical studies have provided additional mechanistic insights while improving the care of patients with inflammatory and neoplastic conditions. This review discusses major advances in the field, focusing on updates in genetic diseases and in studies of clinical jakinibs in human disease.
Subject(s)
Genetic Diseases, Inborn/drug therapy , Janus Kinase Inhibitors/therapeutic use , Janus Kinases/immunology , STAT Transcription Factors/immunology , Animals , Cytokines/immunology , Genetic Diseases, Inborn/immunology , Humans , Janus Kinases/genetics , Mutation , STAT Transcription Factors/genetics , Signal TransductionSubject(s)
Asymptomatic Infections , COVID-19/virology , Feces/virology , Genetic Diseases, Inborn/virology , Immunologic Deficiency Syndromes/virology , SARS-CoV-2/isolation & purification , Virus Shedding , Child , Child, Preschool , Female , Genetic Diseases, Inborn/immunology , Humans , Immunologic Deficiency Syndromes/immunology , Infant , MaleABSTRACT
Monogenic diseases of the immune system, also known as inborn errors of immunity (IEIs), are caused by single-gene mutations and result in immune deficiency and dysregulation. More than 400 monogenic diseases have been described to date, and this number is rapidly expanding. The increasing availability of next-generation sequencing is now facilitating the diagnosis of IEIs. It is known that IEIs can predispose a person to not only infectious diseases but also cancer and immune disorders, such as inflammatory, autoimmune, and atopic diseases. IEIs with eosinophilia and atopic diseases can occur in several disorders. IEIs with eosinophilia have provided insights into human immunity and the pathogenesis of allergic diseases. Eosinophilia is not a rare finding in clinical practice, and it often poses problems in terms of etiologic research and differential diagnoses. Secondary eosinophilia is the most common form. The main underlying conditions are infectious diseases such as parasitic infections, allergic disorders, drug reactions, and of course IEIs. In clinical settings, the recognition of IEIs in the context of an allergic phenotype with eosinophilia is critical for prompt diagnosis and appropriate treatment aimed at modulating pathophysiological mechanisms and improving clinical symptoms.
Subject(s)
Eosinophilia/immunology , Genetic Diseases, Inborn/immunology , Immune System Diseases/immunology , Actins/immunology , Animals , Cytokines/immunology , Humans , Immune Tolerance , Receptors, Antigen, T-Cell/immunology , T-Box Domain Proteins/deficiency , T-Box Domain Proteins/immunology , T-Lymphocytes/immunologyABSTRACT
STAT2 is distinguished from other STAT family members by its exclusive involvement in type I and III interferon (IFN-I/III) signaling pathways, and its unique behavior as both positive and negative regulator of IFN-I signaling. The clinical relevance of these opposing STAT2 functions is exemplified by monogenic diseases of STAT2. Autosomal recessive STAT2 deficiency results in heightened susceptibility to severe and/or recurrent viral disease, whereas homozygous missense substitution of the STAT2-R148 residue is associated with severe type I interferonopathy due to loss of STAT2 negative regulation. Here we review the clinical presentation, pathogenesis, and management of these disorders of STAT2.
Subject(s)
Genetic Diseases, Inborn/genetics , Immune System Diseases/genetics , Interferon Type I/immunology , STAT2 Transcription Factor/genetics , Virus Diseases/genetics , Animals , Gain of Function Mutation , Genetic Diseases, Inborn/immunology , Genetic Predisposition to Disease , Humans , Immune System Diseases/immunology , Loss of Function Mutation , Phenotype , STAT2 Transcription Factor/chemistry , STAT2 Transcription Factor/immunology , Virus Diseases/immunologySubject(s)
Eye Diseases/diagnosis , Genetic Diseases, Inborn/diagnosis , Microfilament Proteins/genetics , Adult , Argentina , Child , Eye Diseases/genetics , Eye Diseases/immunology , Genetic Diseases, Inborn/genetics , Genetic Diseases, Inborn/immunology , Humans , Leukopenia/diagnosis , Leukopenia/genetics , Leukopenia/immunology , Male , Siblings , Young AdultABSTRACT
Toll-like receptors (TLRs) are pattern recognition receptors that play a central role in the development and function of the immune system. TLR signaling promotes the earliest emergence of hematopoietic cells during development, and thereafter influences the fate and function of both primitive and effector immune cell types. Aberrant TLR signaling is associated with hematopoietic and immune system dysfunction, and both loss- and gain-of- function variants in TLR signaling-associated genes have been linked to specific infection susceptibilities and immune defects. Herein, we will review the role of TLR signaling in immune system development and the growing number of heritable defects in TLR signaling that lead to inborn errors of immunity.
Subject(s)
Genetic Diseases, Inborn , Immune System Diseases , Signal Transduction , Toll-Like Receptors , Animals , Genetic Diseases, Inborn/genetics , Genetic Diseases, Inborn/immunology , Humans , Immune System Diseases/genetics , Immune System Diseases/immunology , Signal Transduction/genetics , Signal Transduction/immunology , Toll-Like Receptors/genetics , Toll-Like Receptors/immunologyABSTRACT
Signal transducer and activator of transcription (STAT)1 heterozygous gain-of-function (GOF) mutations are known to induce immune dysregulation and chronic mucocutaneous candidiasis (CMCC). Previous reports suggest an association between demodicosis and STAT1 GOF. However, immune characterization of these patients is lacking. Here, we present a retrospective analysis of patients with immune dysregulation and STAT1 GOF who presented with facial and ocular demodicosis. In-depth immune phenotyping and functional studies were used to characterize the patients. We identified five patients (three males) from two non-consanguineous Jewish families. The mean age at presentation was 11.11 (range = 0.58-24) years. Clinical presentation included CMCC, chronic demodicosis and immune dysregulation in all patients. Whole-exome and Sanger sequencing revealed a novel heterozygous c.1386C>A; p.S462R STAT1 GOF mutation in four of the five patients. Immunophenotyping demonstrated increased phosphorylated signal transducer and activator of transcription in response to interferon-α stimuli in all patients. The patients also exhibited decreased T cell proliferation capacity and low counts of interleukin-17-producing T cells, as well as low forkhead box protein 3+ regulatory T cells. Specific antibody deficiency was noted in one patient. Treatment for demodicosis included topical ivermectin and metronidazole. Demodicosis may indicate an underlying primary immune deficiency and can be found in patients with STAT1 GOF. Thus, the management of patients with chronic demodicosis should include an immunogenetic evaluation.
Subject(s)
Gain of Function Mutation , Genetic Diseases, Inborn , Immune System Diseases , Mite Infestations , Mites/immunology , STAT1 Transcription Factor , Skin Diseases, Parasitic , Adolescent , Adult , Animals , Child , Chronic Disease , Female , Genetic Diseases, Inborn/genetics , Genetic Diseases, Inborn/immunology , Genetic Diseases, Inborn/parasitology , Humans , Immune System Diseases/genetics , Immune System Diseases/immunology , Immune System Diseases/parasitology , Infant , Male , Middle Aged , Mite Infestations/genetics , Mite Infestations/immunology , Retrospective Studies , STAT1 Transcription Factor/genetics , STAT1 Transcription Factor/immunology , Skin Diseases, Parasitic/genetics , Skin Diseases, Parasitic/immunologyABSTRACT
BACKGROUND: Hereditary alpha-tryptasemia (HαT) is characterized by elevated basal serum tryptase due to increased copies of the TPSAB1 gene. Individuals with HαT frequently present with multisystem complaints, including anaphylaxis and seemingly functional gastrointestinal (GI) symptoms. OBJECTIVE: We sought to determine the prevalence of HαT in an irritable bowel syndrome cohort and associated immunologic characteristics that may distinguish patients with HαT from patients without HαT. METHODS: Tryptase genotyping by droplet digital PCR, flow cytometry, cytometry by time-of-flight, immunohistochemistry, and other molecular biology techniques was used. RESULTS: HαT prevalence in a large irritable bowel syndrome cohort was 5% (N = 8/158). Immunophenotyping of HαT PBMCs (N ≥ 27) revealed increased total and class-switched memory B cells. In the small bowel, expansion of tissue mast cells with expression of CD203c, HLA-DR, and FcεRI, higher intestinal epithelial cell pyroptosis, and increased class-switched memory B cells were observed. IgG profiles in sera from individuals with HαT (N = 21) significantly differed from those in individuals with quiescent Crohn disease (N = 20) and non-HαT controls (N = 19), with increased antibodies directed against GI-associated proteins identified in individuals with HαT. CONCLUSIONS: Increased mast cell number and intestinal epithelial cell pyroptosis in the small intestine, and class-switched memory B cells in both the gut and peripheral blood associated with IgG reactive to GI-related proteins, distinguish HαT from functional GI disease. These innate and adaptive immunologic findings identified in association with HαT are suggestive of subclinical intestinal inflammation in symptomatic individuals.
Subject(s)
Gastrointestinal Diseases , Genetic Diseases, Inborn , Immunoglobulin G/immunology , Intestine, Small/immunology , Mastocytosis , Tryptases , Adult , Epithelial Cells/immunology , Female , Gastrointestinal Diseases/blood , Gastrointestinal Diseases/genetics , Gastrointestinal Diseases/immunology , Gastrointestinal Diseases/pathology , Genetic Diseases, Inborn/blood , Genetic Diseases, Inborn/genetics , Genetic Diseases, Inborn/immunology , Genetic Diseases, Inborn/pathology , Genotype , Humans , Immunoglobulin G/blood , Intestine, Small/cytology , Intestine, Small/pathology , Male , Mast Cells/immunology , Mastocytosis/blood , Mastocytosis/genetics , Mastocytosis/immunology , Mastocytosis/pathology , Middle Aged , Pyroptosis , Tryptases/blood , Tryptases/genetics , Young AdultABSTRACT
The mechanisms that maintain intestinal homeostasis despite constant exposure of the gut surface to multiple environmental antigens and to billions of microbes have been scrutinized over the past 20 years with the goals to gain basic knowledge, but also to elucidate the pathogenesis of inflammatory bowel diseases (IBD) and to identify therapeutic targets for these severe diseases. Considerable insight has been obtained from studies based on gene inactivation in mice as well as from genome wide screens for genetic variants predisposing to human IBD. These studies are, however, not sufficient to delineate which pathways play key nonredundant role in the human intestinal barrier and to hierarchize their respective contribution. Here, we intend to illustrate how such insight can be derived from the study of human Mendelian diseases, in which severe intestinal pathology results from single gene defects that impair epithelial and or hematopoietic immune cell functions. We suggest that these diseases offer the unique opportunity to study in depth the pathogenic mechanisms leading to perturbation of intestinal homeostasis in humans. Furthermore, molecular dissection of monogenic intestinal diseases highlights key pathways that might be druggable and therapeutically targeted in common forms of IBD.
Subject(s)
Host Microbial Interactions/immunology , Immunity, Mucosal , Immunomodulation , Intestinal Mucosa/physiology , Adaptive Immunity , Animals , Biological Transport , Biomarkers , Cell Differentiation/genetics , Cell Differentiation/immunology , Disease Susceptibility , Enterocytes/cytology , Enterocytes/immunology , Enterocytes/metabolism , Gene Expression Regulation , Genetic Diseases, Inborn/genetics , Genetic Diseases, Inborn/immunology , Genetic Predisposition to Disease , Hematopoiesis/genetics , Hematopoiesis/immunology , Homeostasis , Host Microbial Interactions/genetics , Humans , Immunity, Innate , Mutation , Signal TransductionABSTRACT
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.
Subject(s)
Autoimmunity , COVID-19/genetics , COVID-19/immunology , Cytokines/physiology , Interferons/physiology , Autoimmune Diseases/complications , Autoimmune Diseases/epidemiology , Autoimmune Diseases/genetics , Autoimmunity/genetics , Autoimmunity/immunology , COVID-19/epidemiology , COVID-19/therapy , Genetic Diseases, Inborn/complications , Genetic Diseases, Inborn/epidemiology , Genetic Diseases, Inborn/immunology , Genetic Predisposition to Disease/genetics , HumansABSTRACT
Yellow fever virus (YFV) live attenuated vaccine can, in rare cases, cause life-threatening disease, typically in patients with no previous history of severe viral illness. Autosomal recessive (AR) complete IFNAR1 deficiency was reported in one 12-yr-old patient. Here, we studied seven other previously healthy patients aged 13 to 80 yr with unexplained life-threatening YFV vaccine-associated disease. One 13-yr-old patient had AR complete IFNAR2 deficiency. Three other patients vaccinated at the ages of 47, 57, and 64 yr had high titers of circulating auto-Abs against at least 14 of the 17 individual type I IFNs. These antibodies were recently shown to underlie at least 10% of cases of life-threatening COVID-19 pneumonia. The auto-Abs were neutralizing in vitro, blocking the protective effect of IFN-α2 against YFV vaccine strains. AR IFNAR1 or IFNAR2 deficiency and neutralizing auto-Abs against type I IFNs thus accounted for more than half the cases of life-threatening YFV vaccine-associated disease studied here. Previously healthy subjects could be tested for both predispositions before anti-YFV vaccination.
Subject(s)
Antibodies, Neutralizing/immunology , Autoantibodies/immunology , Autoimmune Diseases , COVID-19 , Genetic Diseases, Inborn , Interferon-alpha , Receptor, Interferon alpha-beta , SARS-CoV-2 , Yellow Fever Vaccine , Yellow fever virus , Adolescent , Adult , Aged , Autoimmune Diseases/genetics , Autoimmune Diseases/immunology , COVID-19/genetics , COVID-19/immunology , Female , Genetic Diseases, Inborn/genetics , Genetic Diseases, Inborn/immunology , HEK293 Cells , Humans , Interferon-alpha/genetics , Interferon-alpha/immunology , Male , Middle Aged , Receptor, Interferon alpha-beta/deficiency , Receptor, Interferon alpha-beta/immunology , SARS-CoV-2/genetics , SARS-CoV-2/immunology , Vaccines, Attenuated/genetics , Vaccines, Attenuated/immunology , Yellow Fever Vaccine/adverse effects , Yellow Fever Vaccine/genetics , Yellow Fever Vaccine/immunology , Yellow fever virus/genetics , Yellow fever virus/immunologyABSTRACT
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.