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Background: Elevated levels of interferon-gamma (IFNγ) have been found in COVID-19 infection, however its role in this setting remains poorly understood. Cases of non-tuberculous mycobacterium (NTM) infections due to anti-IFNγ autoantibodies (Ab) were first reported in 2004. NTM and COVID-19 co-infection in a patient with acquired IFNγ deficiency has not previously been described. The impact of anti-IFNγ Ab on the severity of COVID-19 has not been previously explored. Objective: We report a case of COVID-19 infection in a patient hospitalised with NTM infection due to acquired IFNγ deficiency caused by anti-IFNγ Ab. We also explore effects of IFNγ Ab on the severity of COVID-19 infection. Methods: Detailed immunological investigations were performed. Bio-rad, Bio-Plex methodology was used to detect anti-IFNγ Ab, titration, IFNγ recovery assay and SARS-CoV-2 serology. Anti-IFNγ Ab were tested in patients with severe (COV-Pat) and health care workers with mild/asymptomatic COVID-19 infection (COV-Asx). Results: Mycobacterium avium intracellulare was diagnosed following bone marrow examination and culture. High titre anti-IFNγ Ab were detected in patient’s serum. The autoantibodies neutralized both endogenously produced and exogenously administered IFNγ. SARS-COV-2 infection was identified during routine inpatient testing. Despite prolonged SARS-COV-2 infection the patient showed only minimal additional symptoms, never developed any significant inflammatory complications and eventually mounted an adequate IgG antibody response to the SARS-COV-2 trimeric S-protein. Elevated titres of anti-IFNγ Ab were detected in COV-Pat and COV-Asx, compared to non-infected healthy controls. The titres were broadly similar between COV-Pat and COV-Asx groups, but much lower compared to patients with acquired IFNγ Ab deficiency. Conclusion: IFN-γ is known to play a central role in hyperinflammatory disease states such as macrophage activation syndrome This study illustrates the potential value of inhibiting IFNγ to prevent pathological inflammatory response to COVID-19.

BackgroundImmune defects in chronic pulmonary aspergillosis (CPA) are poorly characterized. We compared peripheral blood cytokine profiles in patients with CPA versus healthy controls and explored the relationship with disease severity.MethodsInterferon-gamma (IFNγ), interleukin (IL)-17, tumor necrosis factor-α, IL-6, IL-12, and IL-10 were measured after in vitro stimulation of whole blood with lipopolysaccharide (LPS), phytohemagglutinin, β-glucan, zymosan (ZYM), IL-12 or IL-18, and combinations. Clinical parameters and mortality were correlated with cytokine production.ResultsCytokine profiles were evaluated in 133 patients (57.1% male, mean age 61 years). In comparison to controls, patients with CPA had significantly reduced production of IFNγ in response to stimulation with β-glucan + IL-12 (312 vs 988 pg/mL), LPS + IL-12 (252 vs 1033 pg/mL), ZYM + IL-12 (996 vs 2347 pg/mL), and IL-18 + IL-12 (7193 vs 12 330 pg/mL). Age >60 (hazard ratio [HR], 1.71; 95% confidence interval [CI], 1.00–2.91; P = .05) and chronic obstructive pulmonary disease (HR, 1.69; 95% CI, 1.03–2.78; P = .039) were associated with worse survival, whereas high IFNγ production in response to beta-glucan + IL-12 stimulation (HR, 0.48; 95% CI, .25–0.92; P = .026) was associated with reduced mortality.ConclusionsPatients with CPA show impaired IFNγ production in peripheral blood in response to stimuli. Defective IFNγ production ability correlates with worse outcomes. Immunotherapy with IFNγ could be beneficial for patients showing impaired IFNγ production in CPA.

Autosomal dominant hyper-IgE syndrome caused by dominant-negative loss-of-function mutations in signal transducer and activator of transcription factor 3 (STAT3) (STAT3-HIES) is a rare primary immunodeficiency with multisystem pathology. The quality of life in patients with STAT3-HIES is determined by not only the progressive, life-limiting pulmonary disease, but also significant skin disease including recurrent infections and abscesses requiring surgery. Our early report indicated that hematopoietic stem cell transplantation might not be effective in patients with STAT3-HIES, although a few subsequent reports have reported successful outcomes. We update on progress of our patient now with over 18 years of follow-up and report on an additional seven cases, all of whom have survived despite demonstrating significant disease-related pathology prior to transplant. We conclude that effective cure of the immunological aspects of the disease and stabilization of even severe lung involvement may be achieved by allogeneic hematopoietic stem cell transplantation. Recurrent skin infections and abscesses may be abolished. Donor TH17 cells may produce comparable levels of IL17A to healthy controls. The future challenge will be to determine which patients should best be offered this treatment and at what point in their disease history.

Purpose of review The current review gives a concise and updated overview of the relative new field of anticytokine autoantibodies (ACAA) and associated infections with a focus on recent findings regarding clinical manifestions, diagnostic and treatments. Recent findings Several recent case reports of unusual presentations of patients with neutralizing autoantibodies to IFN-γ and granulocyt macrophage colony-stimulating factor and expand the spectrum of clinical manifestations and suggest that anticytokine-mediated acquired immunodeficiency causing susceptibility to infection may be underdiagnosed. There is an expanding geographical distribution of antigranulocyt macrophage colony-stimulating factor associated Cryptococcus gattii infection. The spectrum of identified infections in patients with neutralizing antibodies to IFN-γ has a strong endemic component. Rituximab or cyclophophamide in addition to antimycobacterials could be a treatment options in refractory cases. NF-κB2 deficiency may be associated with a complex pattern of high titre neutralizing ACAA similar to autoimmune polyglandular syndrome type I and Thymoma. New technique for the detection of anticytokine antibodies are presented. Quantiferon testing, which is widely available for TB-diagnostic, may be repurposed to detect anti-IFN-γ autoantibodies. We propose that this test could be as well used to show if they are neutralizing. Summary ACAA are an emerging cause of acquired immunodeficiency which is likely underdiagnosed. Recent case reports document expanding spectra of clinical manifestations. NF-κB2 deficiency may be associated with a complex anti cytokine autoantibody pattern.

Vaccines remain the cornerstone for containing the SARS-CoV-2 pandemic. mRNA vaccines provide protection in clinical trials using a two-dose approach, separated by a three to four week gap. UK policy in 2021 is to extend the dosing interval from three to twelve weeks and other countries are likely to follow suit given the demand for mRNA vaccines and ongoing uncontrolled transmission. There is a paucity of data in the elderly, even though these individuals are the first to receive vaccines due to risk of severe disease. Here we assessed real world immune responses following vaccination with mRNA-based vaccine BNT162b2. Median age was 81 years amongst 101 participants after the first dose of the BNT162b2 vaccine. Geometric mean neutralisation titres in participants over 80 years old after the first dose were lower than in younger individuals [83.4 (95% CI 52.0-133.7) vs 46.6 (95% CI 33.5-64.8) p 0.01]. A lower proportion of participants 80 years and older achieved adequate neutralisation titre of >1:20 for 50% neutralisation as compared to those under 80 (21% vs 51%, p 0.003). Binding IgG responses correlated with neutralisation. Sera from participants in both age groups showed significantly lower neutralisation potency against B.1.1.7 Spike pseudotyped viruses as compared to wild type. The adjusted ORs for inadequate neutralisation in the 80 years and above age group were 3.7 (95% CI 1.2-11.2) and 4.4 (95% CI 1.5-12.6) against wild type and B.1.1.7 pseudotyped viruses. We observed a trend towards lower somatic hypermutation in participants with suboptimal neutralisation, and elderly participants demonstrated clear reduction in class switched somatic hypermutation, driven by the IgA1/2 isotype. SARS-CoV-2 Spike specific T- cell IFN𝛾 and IL-2 responses were impaired in the older age group after 1 dose and although IFN𝛾 increased between vaccine doses, IL-2 responses did not significantly increase. There was a significantly higher risk of suboptimal neutralising antibody and T cell response following first dose vaccination with BNT162b2 in half of participants above the age of 80, persisting up to 12 weeks. These high risk populations warrant specific measures in order to mitigate against vaccine failure, particularly where SARS-CoV-2 variants of concern are circulating.

Background Vaccines remain the cornerstone for containing the SARS-CoV-2 pandemic. mRNA vaccines provide protection in clinical trials using a two-dose approach, separated by a three to four week gap. UK policy in 2021 is to extend the dosing interval from three to twelve weeks. There is a paucity of data in the elderly, even though these individuals are the first to receive vaccines due to risk of severe disease. Here we assessed real world immune responses following vaccination with mRNA-based vaccine BNT162b2. Methods We did a prospective cohort study of individuals presenting for first dose vaccination. Following the first and second doses of the BNT162b2 vaccine, we measured IFNγ T cell responses, as well as binding antibody (IgA, IgG and IgG1-4) responses to Spike and Spike RBD. We also measured neutralising antibody responses to Spike in sera using a lentiviral pseudotyping system. We correlated age with immune responses and compared responses after the first and second doses. Findings Median age was 63.5 years amongst 42 participants. Three weeks after the first dose a lower proportion of participants over 80 years old achieved adequate neutralisation titre of >1:20 for 50% neutralisation as compared to those under 80 (8/17 versus 19/24, p=0.03). Geometric mean neutralisation titres in this age group after the first dose were lower than in younger individuals (p Interpretation A high proportion of individuals above the age of 80 have suboptimal neutralising antibody responses following first dose vaccination with BNT162b2, cautioning against extending the dosing interval in this high risk population. Research in Context Evidence before this study We searched PubMed for research articles published from June 1st 2020 until February 8th 2021. We limited our search to English language papers. We used the following terms: “SARS-CoV-2” AND “vaccine” OR “BNT162b2” OR “Pfizer/BioNTech”. We identified only one paper. It showed lower neutralising antibody responses following the first dose of BNT162b in a small group of 12 individuals over 65 compared to those under 65. There were no data for patients above 82 years of age and no data on T cell responses by age. We did not find pre-prints on age related heterogeneity in individuals immunised with the Pfizer/BioNtech mRNA vaccine. What this study adds We show real world immune responses in forty two individuals to BNT162b2, spanning both T and B cell arms. We show that a high proportion of individuals above the age of 80 have suboptimal neutralising antibody responses following first dose vaccination with BNT162b2. The second dose generates robust responses in these poor responders. We quantify SARS-CoV-2 Spike and receptor binding domain (RBD) IgA and IgG isotypes as well as IgG subclasses. Finally we show that SARS-CoV-2 specific T cell responses are robustly induced by first dose vaccination and are not impacted by age. Implications of all the available evidence These data caution against extending the dosing interval of BNT162b2 in the elderly population, particularly during periods of high transmission, and also where there is risk of infection with variants that are less susceptible to vaccine-elicited neutralising antibodies.

SARS-CoV-2 transmission is uncontrolled in many parts of the world, compounded in some areas by higher transmission potential of the B1.1.7 variant now seen in 50 countries. It is unclear whether responses to SARS-CoV-2 vaccines based on the prototypic strain will be impacted by mutations found in B.1.1.7. Here we assessed immune responses following vaccination with mRNA-based vaccine BNT162b2. We measured neutralising antibody responses following a single immunization using pseudoviruses expressing the wild-type Spike protein or the 8 mutations found in the B.1.1.7 Spike protein. The vaccine sera exhibited a broad range of neutralizing titres against the wild-type pseudoviruses (

Severe Acute Respiratory Syndrome Coronavirus-2 (SARS-CoV-2) transmission is uncontrolled in many parts of the world, compounded in some areas by higher transmission potential of the B1.1.7 variant now seen in 50 countries. It is unclear whether responses to SARS-CoV-2 vaccines based on the prototypic strain will be impacted by mutations found in B.1.1.7. Here we assessed immune responses following vaccination with mRNA-based vaccine BNT162b2. We measured neutralising antibody responses following a single immunization using pseudoviruses expressing the wild-type Spike protein or the 8 amino acid mutations found in the B.1.1.7 spike protein. The vaccine sera exhibited a broad range of neutralising titres against the wild-type pseudoviruses that were modestly reduced against B.1.1.7 variant. This reduction was also evident in sera from some convalescent patients. Decreased B.1.1.7 neutralisation was also observed with monoclonal antibodies targeting the N-terminal domain (9 out of 10), the Receptor Binding Motif (RBM) (5 out of 31), but not in neutralising mAbs binding outside the RBM. Introduction of the E484K mutation in a B.1.1.7 background to reflect newly emerging viruses in the UK led to a more substantial loss of neutralising activity by vaccine-elicited antibodies and mAbs (19 out of 31) over that conferred by the B.1.1.7 mutations alone. E484K emergence on a B.1.1.7 background represents a threat to the vaccine BNT162b.

Background: Vaccines remain the cornerstone for containing the SARS-CoV-2 pandemic. mRNA vaccines provide protection in clinical trials using a two-dose approach, separated by a three to four week gap. UK policy in 2021 is to extend the dosing interval from three to twelve weeks. There is a paucity of data in the elderly, even though these individuals are the first to receive vaccines due to risk of severe disease. Here we assessed real world immune responses following vaccination with mRNA-based vaccine BNT162b2. Methods: We did a prospective cohort study of individuals presenting for first dose vaccination. Following the first and second doses of the BNT162b2 vaccine, we measured IFNγ T cell responses, as well as binding antibody (IgA, IgG and IgG1-4) responses to Spike and Spike RBD. We also measured neutralising antibody responses to Spike in sera using a lentiviral pseudotyping system. We correlated age with immune responses and compared responses after the first and second doses. Findings: Median age was 63.5 years amongst 42 participants. Three weeks after the first dose a lower proportion of participants over 80 years old achieved adequate neutralisation titre of >1:20 for 50% neutralisation as compared to those under 80 (8/17 versus 19/24, p=0.03). Geometric mean neutralisation titres in this age group after the first dose were lower than in younger individuals (p

Increased extracellular sodium activates Th17 cells, which provide protection from bacterial and fungal infections. Whilst high salt diets have been shown to worsen autoimmune disease, the immunological consequences of clinical salt depletion are unknown. Here, we investigate immunity in patients with inherited salt-losing tubulopathies (SLT). Forty-seven genotyped SLT patients (with Bartter, Gitelman or EAST Syndromes) are recruited. Clinical features of dysregulated immunity are recorded with a standardised questionnaire and immunological investigations of IL-17 responsiveness undertaken. The effects of altering extracellular ionic concentrations on immune responses are then assessed. Patients are hypokalaemic and hypomagnesaemic, with reduced interstitial sodium stores determined by 23Na-magnetic resonance imaging. SLT patients report increased mucosal infections and allergic disease compared to age-matched controls. Aligned with their clinical phenotype, SLT patients have an increased ratio of Th2:Th17 cells. SLT Th17 and Tc17 polarisation is reduced in vitro, yet STAT1 and STAT3 phosphorylation and calcium flux following T cell activation are unaffected. In control cells, the addition of extracellular sodium (+40 mM), potassium (+2 mM), or magnesium (+1 mM) reduces Th2:Th17 ratio and augments Th17 polarisation. Our results thus show that the ionic environment typical in SLT impairs IL-17 immunity, but the intracellular pathways that mediate salt-driven Th17 polarisation are intact and in vitro IL-17 responses can be reinvigorated by increasing extracellular sodium concentration. Whether better correction of extracellular ions can rescue the immunophenotype in vivo in SLT patients remains unknown., Salt levels in culture affect the polarisation of Th17 cells, which normally protect the host from fungal and bacterial infections. Here, the authors study patients with salt-losing tubulopathies (SLT) to find that, while Th17 immunity is dampened in SLT patients, their Th17-inducing signaling pathways are intact and can be reinvigorated by exogenous salt.

Autoantibodies against cytokines have been associated with immunodeficiency, susceptibility to infectious diseases, autoimmunity and inflammation in humans, but have not yet been investigated in the Veterinary field so far. The aim of the current study was to determine the presence of anti-cytokine autoantibodies in canines suffering from various conditions including recurrent infections, autoimmune diseases and cancer in comparison to healthy controls. This is the first report of the presence of autoantibodies against cytokines in dogs. A total of 101 serum samples (51 patients and 50 clinically healthy dogs) from the state of Mexico and surroundings were analysed using a multiplex bead-based flow cytometry assay. Results show significant levels of various anti-cytokine autoantibodies in diseased dogs but not in healthy controls. In addition we show distinct associations of various disease types to the specificity of anti-cytokine autoantibodies and to response complexities. Apart from the direct functional/causal implication of anti-cytokine auto-antibodies on disease processes, this findings point to the possibility to use anti-cytokine response patterns as diagnostic tools.

Background Pneumococcal immunization is recommended in children with cystic fibrosis (CF). To date, however, there are no published studies on the efficacy of pneumococcal vaccination in this group of patients. Methods We carried out a retrospective study of serotype-specific pneumococcal antibody responses to immunization with Prevenar 7 and Pneumovax II in a cohort of children with CF. Results Nine children had been immunized with Prevenar 7, and all had serotype-specific pneumococcal antibody levels in the protective range (>0.35mg/L) to all 7 immunizing serotypes. In contrast, only 7 of 33 patients (21%) immunized with Pneumovax II made protective antibody responses to all 7 serotypes, and 3 failed to make protective antibodies to any of the serotypes. Controlling for age as a confounder in the analysis, children with impaired antibody responses to pneumococcal polysaccharide (Pneumovax II) immunization had lower Shwachman–Kulczycki scores than children with normal polysaccharide antibody responses. All isolates of Pseudomonas aeruginosa occurred in patients with impaired anti-pneumococcal antibody responses, and a broader range of respiratory pathogens was isolated from these children. Conclusions Impaired antibody responses to immunization with Pneumovax II are common in children with CF and this may be associated with increased disease severity.

G6PC3 deficiency typically causes severe congenital neutropenia, associated with susceptibility to infections, cardiac and urogenital abnormalities. However, here we describe two boys of Pakistani origin who were found to have G6PC3 deficiency due to c.130 C > T mutation, but who have clinical phenotypes that are typical for a systemic autoinflammatory syndrome. The index case presented with combination of unexplained fevers, severe mucosal ulcers, abdominal symptoms, and inflammatory arthritis. He eventually fully responded to anti-TNF therapy. In this study, we show that compared with healthy controls, neutrophils and monocytes from patients have reduced glycolytic reserve. Considering that healthy myeloid cells have been shown to switch their metabolic pathways to glycolysis in response to inflammatory cues, we studied what impact this might have on production of the inflammatory cytokines. We have demonstrated that patients' monocytes, in response to lipopolysaccharide, show significantly increased production of IL-1β and IL-18, which is NLRP3 inflammasome dependent. Furthermore, additional whole blood assays have also shown an enhanced production of IL-6 and TNF from the patients' cells. These cases provide further proof that autoinflammatory complications are also seen within the spectrum of primary immune deficiencies, and resulting from a wider dysregulation of the immune responses.

At the population level, rheumatoid arthritis (RA) is generally viewed as autoimmune in nature with a small subgroup of cases having a palindromic form or systemic autoinflammatory disorder (SAID) phenotype. Herein, we describe resistant cases of classical autoantibody associated RA that had clinical, genetic and therapeutic responses indicative of coexistent autoinflammatory disease. Five patients with clinically overlapping features between RA and SAID including polysynovitis and autoantibody/shared epitope positivity, and who had abrupt severe self-limiting attacks including fevers and serositis, are described. Mutations or single nucleotide polymorphisms in recognised autoinflammatory pathways were evident. Generally, these cases responded poorly to conventional Disease-modifying anti-rheumatic drugs (DMARD) treatment with some excellent responses to colchicine or interleukin 1 pathway blockade. A subgroup of RA cases have a mixed autoimmune-autoinflammatory phenotype and genotype with therapeutic implications.

Answers from Exomes Exome sequencing, which targets only the protein-coding regions of the genome, has the potential to identify the underlying genetic causes of rare inherited diseases. Angulo et al. (p. 866 , published online 17 October; see Perspective by Conley and Fruman ) performed exome sequencing of individuals from seven unrelated families with severe, recurrent respiratory infections. The patients carried the same mutation in the gene coding for the catalytic subunit of phosphoinositide 3-kinase δ (PI3Kδ). The mutation caused aberrant activation of this kinase, which plays a key role in immune cell signaling. Drugs inhibiting PI3Kδ are already in clinical trials for other disorders.

Concise overview of the field of anticytokine autoantibodies with a focus on recent developments.Advances in particular in the analysis of autoantibodies to IFNγ, granulocyte-macrophage colony-stimulating factor (GM-CSF) and type I IFN are presented. The target epitope for anti-IFNγ autoantibodies has been found to have high homology to a protein from Aspergillus suggesting molecular mimicry as a mechanism of breaking self-tolerance. A treatment strategy using a recombinant, epitope-depleted version of IFNγ is suggested. Autoantibodies to GM-CSF are associated with disseminated Crytococcus and Nocardia infections thus expanding the spectrum of associated diseases beyond pulmonary alveolar proteinosis. Detailed analysis of anti-GM-CSF autoantibody clones derived from pulmonary alveolar proteinosis patients show evidence of high somatic mutation suggesting T cell-dependent affinity maturation; full GM-CSF neutralization is achieved by synergistic binding of antibodies targeting various distinct noncross-reactive epitopes and leading to antigen sequestration and Fc-mediated clearance. Single mAbs in contrast may lead to higher GM-CSF bioavailability. Anti type I IFN-specific autoantibodies derived from autoimmune polyglandular syndrome type I patients are of extreme high affinity and negatively correlate with the incidence of type I diabetes and may be thus considered to be protective. Hypomorphic severe combined immune deficiency may be associated with complex anticytokine patterns and the emergence of anti type I IFN autoantibodies correlates with severe viral infection histories.Anticytokine autoantibodies may cause susceptibility to infections. In autoimmune/autoinflammatory conditions, anticytokine autoantibodies may be protective or promote disease.

Although neonatal vaccination with bacille Calmette-Guérin (BCG) is considered to be safe, complications with disseminated disease are associated with underlying immuno-deficiency disorders. A BCG-vaccinated 4-month-old girl of Sri Lankan parentage developed progressive left axillary lymphadenopathy and severe bronchopneumonia. Lymph node biopsy demonstrated epithelioid granulomata and acid-fast bacilli. An older sibling had had a similar clinical presentation and the outcome had been fatal. Investigation for immuno-deficiency detected complete IL12RB1 deficiency. Full recovery followed a prolonged course of anti-tuberculous chemotherapy. She was put on lifelong isoniazid prophylaxis. In HIV-negative infants with unusual complications related to BCG vaccination, a primary immuno-deficiency disorder should be considered.

Background: We developed a cost-efficient modular system for multiplex analysis of the multiple autoantibodies that characterize systemic rheumatoid diseases. Methods: The nanodot array luminometric immunoassay (NALIA) system consists of conventional 96-well membrane-bottomed plates in which antigens or antibodies are adsorbed onto the underside of the membrane. Current arrays use a 5 × 5 format (25 dots/well), which allows 10 analytes to be measured in duplicate: double-stranded DNA (dsDNA), centromere protein B (CENP-B), PCNA, Sm, Sm ribonucleoprotein (Sm-RNP), U1-snRNP, Scl70, SSA/Ro, SSB/La, Jo-1, and controls. The test fluid, control sera, and subsequent reagents are drawn through the membrane. The captured analytes are quantified by monitoring chemiluminescence with a charge-coupled device (CCD) and analyzed with commercial array software. Results: The assay can detect Conclusion: The NALIA approach promises to provide a highly economical platform for a wide range of applications that require assays of multiple analytes. The degree of concordance of our results with a conventional reagent set was no less than that occurring between different commercial products. A sample of serum from a finger stick provides a volume sufficient to perform the array assay.

We evaluated a patient with disseminated Mycobacterium tuberculosis and Mycobacterium chelonae infection, of which he died. He also developed autoimmune (type I) diabetes and primary hypothyroidism. His serum contained a high titer of immunoglobulin G autoantibody to interferon-gamma (IFN-gamma) capable of blocking in vitro responses to this cytokine by peripheral blood mononuclear cells from normal donors. These results suggest that autoantibodies to IFN-gamma can induce susceptibility to disseminated mycobacterial infection, which may be refractory to chemotherapy.

In the last 6 years, considerable advances have been made in the molecular analysis of a rare clinical syndrome: Mendelian susceptibility to mycobacterial disease (MSMD). Infection with poorly virulent environmental non-tuberculous mycobacteria (NTM) or vaccination with bacillus Calmette-Guerin (BCG) may cause disseminating and even fatal disease in individuals suffering from this syndrome. Mutations in five genes (IFNGR1, IFNGR2, STAT1, IL12B and IL12RB1) have been shown to be responsible for MSMD and further allelic heterogeneity accounts for the existence of nine distinct inherited disorders. All of these disorders are caused by impaired IFNgamma-mediated immunity. These results have important medical and biological implications. In this report, we update the disease-causing mutations reported in the literature.

Complete deficiency of either of the two human interferon (IFN)-gamma receptor components, the ligand-binding IFN-gammaR1 chain and the signaling IFN-gammaR2 chain, is invariably associated with early-onset infection caused by bacille Calmette-Guérin vaccines and/or environmental nontuberculous mycobacteria, poor granuloma formation, and a fatal outcome in childhood. Partial IFN-gammaR1 deficiency is associated with a milder histopathologic and clinical phenotype. Cells from a 20-year-old healthy person with a history of curable infections due to bacille Calmette-Guérin and Mycobacterium abscessus and mature granulomas in childhood were investigated. There was a homozygous nucleotide substitution in IFNGR2, causing an amino acid substitution in the extracellular region of the encoded receptor. Cell surface IFN-gammaR2 were detected by flow cytometry. Cellular responses to IFN-gamma were impaired but not abolished. Transfection with the wild-type IFNGR2 gene restored full responsiveness to IFN-gamma. This is the first demonstration of partial IFN-gammaR2 deficiency in humans.

Background Anti-cytokine autoantibodies (ACAAs) are pathogenic in a handful of rare immunodeficiencies. However, the prevalence and significance of other ACAAs across immunodeficiencies have not yet been described. Objective We profiled ACAAs in a diverse cohort of serum samples from patients with immunodeficiency and assessed the sensitivity and specificity of protein microarrays for ACAA identification and discovery. Methods Highly multiplexed protein microarrays were designed and fabricated. Blinded serum samples from a cohort of 58 immunodeficiency patients and healthy control subjects were used to probe microarrays. Unsupervised hierarchical clustering was used to identify clusters of reactivity, and after unblinding, significance analysis of microarrays was used to identify disease-specific autoantibodies. A bead-based assay was used to validate protein microarray results. Blocking activity of serum containing ACAAs was measured in vitro . Results Protein microarrays were highly sensitive and specific for the detection of ACAAs in patients with autoimmune polyendocrine syndrome type I and pulmonary alveolar proteinosis, detecting ACAA levels consistent with those reported in the published literature. Protein microarray results were validated by using an independent bead-based assay. To confirm the functional significance of these ACAAs, we tested and confirmed the blocking activity of select ACAAs in vitro . Conclusion Protein microarrays are a powerful tool for ACAA detection and discovery, and they hold promise as a diagnostic for the evaluation and monitoring of clinical immunodeficiency.

Most patients with autoimmune polyendocrine syndrome type I (APS-I) display chronic mucocutaneous candidiasis (CMC). We hypothesized that this CMC might result from autoimmunity to interleukin (IL)-17 cytokines. We found high titers of autoantibodies (auto-Abs) against IL-17A, IL-17F, and/or IL-22 in the sera of all 33 patients tested, as detected by multiplex particle-based flow cytometry. The auto-Abs against IL-17A, IL-17F, and IL-22 were specific in the five patients tested, as shown by Western blotting. The auto-Abs against IL-17A were neutralizing in the only patient tested, as shown by bioassays of IL-17A activity. None of the 37 healthy controls and none of the 103 patients with other autoimmune disorders tested had such auto-Abs. None of the patients with APS-I had auto-Abs against cytokines previously shown to cause other well-defined clinical syndromes in other patients (IL-6, interferon [IFN]-γ, or granulocyte/macrophage colony-stimulating factor) or against other cytokines (IL-1β, IL-10, IL-12, IL-18, IL-21, IL-23, IL-26, IFN-β, tumor necrosis factor [α], or transforming growth factor β). These findings suggest that auto-Abs against IL-17A, IL-17F, and IL-22 may cause CMC in patients with APS-I.