Stability of gut microbiome after COVID-19 vaccination in healthy and immuno-compromised individuals.

Bidirectional interactions between the immune system and the gut microbiota are key contributors to various physiological functions. Immune-associated diseases such as cancer and autoimmunity, and efficacy of immunomodulatory therapies, have been linked to microbiome variation. Although COVID-19 infection has been shown to cause microbial dysbiosis, it remains understudied whether the inflammatory response associated with vaccination also impacts the microbiota. Here, we investigate the temporal impact of COVID-19 vaccination on the gut microbiome in healthy and immuno-compromised individuals; the latter included patients with primary immunodeficiency and cancer patients on immunomodulating therapies. We find that the gut microbiome remained remarkably stable post-vaccination irrespective of diverse immune status, vaccine response, and microbial composition spanned by the cohort. The stability is evident at all evaluated levels including diversity, phylum, species, and functional capacity. Our results indicate the resilience of the gut microbiome to host immune changes triggered by COVID-19 vaccination and suggest minimal, if any, impact on microbiome-mediated processes. These findings encourage vaccine acceptance, particularly when contrasted with the significant microbiome shifts observed during COVID-19 infection.

Serum and Tissue Biomarkers Associated With Composite of Relevant Endpoints for Sjögren Syndrome (CRESS) and Sjögren Tool for Assessing Response (STAR) to B Cell-Targeted Therapy in the Trial of Anti-B Cell Therapy in Patients With Primary Sjögren Syndrome (TRACTISS).

OBJECTIVE: This study aimed to identify peripheral and salivary gland (SG) biomarkers of response/resistance to B cell depletion based on the novel concise Composite of Relevant Endpoints for Sjögren Syndrome (cCRESS) and candidate Sjögren Tool for Assessing Response (STAR) composite endpoints. METHODS: Longitudinal analysis of peripheral blood and SG biopsies was performed pre- and post-treatment from the Trial of Anti-B Cell Therapy in Patients With Primary Sjögren Syndrome (TRACTISS) combining flow cytometry immunophenotyping, serum cytokines, and SG bulk RNA sequencing. RESULTS: Rituximab treatment prevented the worsening of SG inflammation observed in the placebo arm, by inhibiting the accumulation of class-switched memory B cells within the SG. Furthermore, rituximab significantly down-regulated genes involved in immune-cell recruitment, lymphoid organization alongside antigen presentation, and T cell co-stimulatory pathways. In the peripheral compartment, rituximab down-regulated immunoglobulins  and auto-antibodies together with pro-inflammatory cytokines and chemokines. Interestingly, patients classified as responders  according to STAR displayed significantly higher baseline levels of C-X-C motif chemokine ligand-13 (CXCL13), interleukin (IL)-22, IL-17A, IL-17F, and tumor necrosis factor-α (TNF-α), whereas a longitudinal analysis of serum T cell-related cytokines showed a selective reduction in both STAR and cCRESS responder patients. Conversely, cCRESS response was better associated with biomarkers of SG immunopathology, with cCRESS-responders showing a significant decrease in SG B cell infiltration and reduced expression of transcriptional gene modules related to T cell costimulation, complement activation, and Fcγ-receptor engagement. Finally, cCRESS and STAR response were associated with a significant improvement in SG exocrine function linked to transcriptional evidence of SG epithelial and metabolic restoration. CONCLUSION: Rituximab modulates both peripheral and SG inflammation, preventing the deterioration of exocrine function with functional and metabolic restoration of the glandular epithelium. Response assessed by newly developed cCRESS and STAR criteria was associated with differential modulation of peripheral and SG biomarkers, emerging as novel tools for patient stratification.

Behçet's patients' response to COVID-19 vaccination.

Immune hyperstimulation by SARS-CoV2 results in multi-system involvement with consequent organ damage not dissimilar to Behçet's Disease (BD). Management of BD includes immunosuppressive medication, which led to concerns that; firstly, SARS-CoV-2 would stimulate BD activity, thrombin, clotting times, TPO antibodies, and the effectiveness and duration of the COVID-19 vaccines' response in this potentially vulnerable group. The main objectives of this study were: to assess BD patients' immune response to the COVID-19 vaccines based on age, gender, disease activity, BD phenotype, and immunomodulatory medication compared to healthy control participants by measuring anti-spike IgG levels. Further to evaluate the effect of the COVID-19 vaccines on T and B cells, immunoglobulins, thrombophilia, thyroid function and COVID-19 antibody production. Patients on immunosuppressive medication had a reduced immune response to COVID-19 vaccines. -Also, patients over 40 years and with the neurologic BD phenotype had lower responses. mRNA COVID-19 vaccines were more effective and had fewer side effects compared to conventional COVID-19 vaccines.

Age-associated B cells predict impaired humoral immunity after COVID-19 vaccination in patients receiving immune checkpoint blockade.

Age-associated B cells (ABC) accumulate with age and in individuals with different immunological disorders, including cancer patients treated with immune checkpoint blockade and those with inborn errors of immunity. Here, we investigate whether ABCs from different conditions are similar and how they impact the longitudinal level of the COVID-19 vaccine response. Single-cell RNA sequencing indicates that ABCs with distinct aetiologies have common transcriptional profiles and can be categorised according to their expression of immune genes, such as the autoimmune regulator (AIRE). Furthermore, higher baseline ABC frequency correlates with decreased levels of antigen-specific memory B cells and reduced neutralising capacity against SARS-CoV-2. ABCs express high levels of the inhibitory FcγRIIB receptor and are distinctive in their ability to bind immune complexes, which could contribute to diminish vaccine responses either directly, or indirectly via enhanced clearance of immune complexed-antigen. Expansion of ABCs may, therefore, serve as a biomarker identifying individuals at risk of suboptimal responses to vaccination.

The efficacy and safety of systemic corticosteroids as first line treatment for granulomatous lymphocytic interstitial lung disease.

BACKGROUND: Granulomatous and lymphocytic interstitial lung disease (gl-ILD) is a major cause of morbidity and mortality among patients with common variable immunodeficiency. Corticosteroids are recommended as first-line treatment for gl-ILD, but evidence for their efficacy is lacking. OBJECTIVES: This study analyzed the effect of high-dose corticosteroids (≥0.3 mg/kg prednisone equivalent) on gl-ILD, measured by high-resolution computed tomography (HRCT) scans, and pulmonary function test (PFT) results. METHODS: Patients who had received high-dose corticosteroids but no other immunosuppressive therapy at the time (n = 56) and who underwent repeated HRCT scanning or PFT (n = 39) during the retrospective and/or prospective phase of the Study of Interstitial Lung Disease in Primary Antibody Deficiency (STILPAD) were included in the analysis. Patients without any immunosuppressive treatment were selected as controls (n = 23). HRCT scans were blinded, randomized, and scored using the Hartman score. Differences between the baseline and follow-up HRCT scans and PFT were analyzed. RESULTS: Treatment with high-dose corticosteroids significantly improved HRCT scores and forced vital capacity. Carbon monoxide diffusion capacity significantly improved in both groups. Of 18 patients, for whom extended follow-up data was available, 13 achieved a long-term, maintenance therapy independent remission. All patients with relapse were retreated with corticosteroids, but only one-fifth of them responded. Two opportunistic infections were found in the corticosteroid treatment group, while overall infection rate was similar between cohorts. CONCLUSIONS: Induction therapy with high-dose corticosteroids improved HRCT scans and PFT results of patients with gl-ILD and achieved long-term remission in 42% of patients. It was not associated with major side effects. Low-dose maintenance therapy provided no benefit and efficacy was poor in relapsing disease.

Outcomes following SARS-CoV-2 infection in patients with primary and secondary immunodeficiency in the UK.

In March 2020, the United Kingdom Primary Immunodeficiency Network (UKPIN) established a registry of cases to collate the outcomes of individuals with PID and SID following SARS-CoV-2 infection and treatment. A total of 310 cases of SARS-CoV-2 infection in individuals with PID or SID have now been reported in the UK. The overall mortality within the cohort was 17.7% (n = 55/310). Individuals with CVID demonstrated an infection fatality rate (IFR) of 18.3% (n = 17/93), individuals with PID receiving IgRT had an IFR of 16.3% (n = 26/159) and individuals with SID, an IFR of 27.2% (n = 25/92). Individuals with PID and SID had higher inpatient mortality and died at a younger age than the general population. Increasing age, low pre-SARS-CoV-2 infection lymphocyte count and the presence of common co-morbidities increased the risk of mortality in PID. Access to specific COVID-19 treatments in this cohort was limited: only 22.9% (n = 33/144) of patients admitted to the hospital received dexamethasone, remdesivir, an anti-SARS-CoV-2 antibody-based therapeutic (e.g. REGN-COV2 or convalescent plasma) or tocilizumab as a monotherapy or in combination. Dexamethasone, remdesivir, and anti-SARS-CoV-2 antibody-based therapeutics appeared efficacious in PID and SID. Compared to the general population, individuals with PID or SID are at high risk of mortality following SARS-CoV-2 infection. Increasing age, low baseline lymphocyte count, and the presence of co-morbidities are additional risk factors for poor outcome in this cohort.

Subcutaneous Gammanorm® by pump or rapid push infusion: Impact of the device on quality of life in adult patients with primary immunodeficiencies.

Many patients with immunodeficiencies require lifelong immunoglobulin replacement therapy (IgRT). In a multicenter, randomized, open-label, crossover, non-inferiority 3-month-trial, we compared the impact of the subcutaneous immunoglobulin Gammanorm® administered via pump or syringe (rapid push). Primary endpoint was the life quality index (LQI), secondary endpoints were QoL (SF36v2), satisfaction (TSQM-11), disease and treatment burden (PRISM), incidence of infections and adverse events (AE), treatment costs, and IgG levels. 28/30 patients completed the study. Most of the endpoints were comparable. Drug administrations with rapid push were more frequent, but reduced total time expenditure and some costs. Of the TSQM-11/LQI/SF36 components only "treatment interference with daily activities" was superior with pump and two QoL domains with rapid push. Both delivery devices showed favorable safety. Rapid push was preferred by 34.5% of patients. It proved to be an efficacious and cost-effective alternative to pumps adding to patient choice and increasing flexibility during long-term IgRT.

A Multi­Center, Open­Label, Single­Arm Trial to Evaluate the Efficacy, Pharmacokinetics, and Safety and Tolerability of IGSC 20% in Subjects with Primary Immunodeficiency.

PURPOSE: The purpose of this phase 3 study was to evaluate the efficacy, pharmacokinetics (PK), and safety of Immune Globulin Subcutaneous (Human), 20% Caprylate/Chromatography Purified (IGSC 20%) in patients with primary immunodeficiency (PI). METHODS: Immunoglobulin treatment-experienced subjects with PI received 52 weeks of IGSC 20% given weekly at the same dose as the subject's previous IgG regimen (DAF 1:1); the minimum dose was 100 mg/kg/week. The primary endpoint was serious bacterial infections (SBIs [null vs alternative hypothesis: SBI rate per person per year ≥ 1 vs < 1]). IgG subclasses and specific pathogen antibody levels were also measured. RESULTS: Sixty-one subjects (19 children [≤ 12 years], 10 adolescents [> 12-16 years], and 32 adults) were enrolled. The rate of SBIs per person per year was 0.017. The 1-sided 99% upper confidence limit was 0.036 (< 1), and the null hypothesis was rejected. The rate of hospitalization due to infection per person per year was 0.017 (2-sided 95% confidence interval: 0.008-0.033) overall. The mean trough total IgG concentrations were comparable to the previous IgG replacement regimen. The average of the individual mean trough ratios (IGSC 20%:previous regimen) was 1.078 (range: 0.83-1.54). The average steady-state mean trough IgG concentrations were 947.64 and 891.37 mg/dL, respectively. Seven subjects had serious treatment-emergent adverse events (TEAEs); none was drug-related. The rate of all TEAEs, including local infusion site reactions, during 3045 IGSC 20% infusions was 0.135. Most TEAEs were mild or moderate. CONCLUSIONS: IGSC 20% demonstrated efficacy and good safety and tolerability in subjects with PI.

Utility of immunology, microbiology, and helminth investigations in clinical assessment of severe asthma.

OBJECTIVE: Systematic assessment of patients with potential severe asthma is key to identification of treatable traits and optimal management. Assessment of antimicrobial immune function is part of that assessment at many centers although there is little evidence-base on its added value in clinical assessment of this patient group. As part of reviewing our local pathway, we have retrospectively reviewed these tests in 327 consecutive referrals to our severe asthma service, in an evaluation to describe the utility of these tests and allow refinement of the local guideline for patient assessment. METHODS AND RESULTS: Serum immunoglobulin concentrations were in the normal range in most patients though 12 patients had serum IgG < 5.5 g/L and many had suboptimal anti-Haemophilus (127 of 249 patients tested) and anti-Pneumococcal (111 of 239) immune responses. As expected many patients had evidence of sensitization to Aspergillus although specific IgG was not confined to those with evidence of allergic sensitization/allergic bronchopulmonary aspergillosis (ABPA). Eighteen of 277 patients tested had serological evidence of Strongyloides infection. Bacteria and/or yeast were cultured from the sputum in 76 out of 110 patients productive of sputum, and the most common microbes cultured were Candida sp. (44 patients), Staphylococcus aureus (21 patients), Haemophilus influenzae (18 patients). CONCLUSIONS: Many patients had evidence of infection, colonization, or sensitization to potential pathogens relevant to asthma. Strongyloides infection was evident in several patients, which may be a major issue when considering the risk of hyper-infection following immunosuppression and supports our local screening strategy.

Measurement of C1-Inhibitor function alone is sufficient for diagnosis of hereditary angioedema.

The World Allergy Organisiation/European Academy of Allergy and Clinical Immunology (WAO/EAACI) 2017/2018 guidelines recommend measuring complement4 levels, followed by C1-inhibitor level and function for diagnosis of hereditary angioedema (HAE). We analysed 6 months' worth of data generated in our laboratory which is a specialist regional immunology service and also provides laboratory service for the Barts Health immunology department, which is a GA2LEN/HAEi-Angioedema Centre of Excellence and Reference (ACARE) and hence, investigates a large number of patients for HAE. We found that an efficient and sensitive approach for laboratory diagnosis of HAE is to only test the C1-inhibitor function. This approach had a sensitivity of 100% and reduced the cost of laboratory investigations for HAE diagnosis by 45%.

Severity of COVID-19 infection in primary Sjögren's syndrome and the emerging evidence of COVID-19-induced xerostomia.

Since the beginning of the COVID-19 disease pandemic caused by the new coronavirus SARS-CoV-2, the disease has claimed over 205M cases (205,338,159) and 4,333,094 deaths (WHO dashboard - accessed 15/08/2021). In addition to the overwhelming impact on healthcare systems treating acutely ill patients, the pandemic has had an impact on all other aspects of health care delivery, including the management of chronic diseases, the risk that is posed in patients with chronic conditions and the risk of the infection itself in those with chronic conditions. Autoimmune rheumatic diseases (ARDs), including primary Sjögren's syndrome (pSS), characterised by immune dysregulation affecting several organs in variable severity, have been of particular interest given the accelerated phase of the immune response in the course of SARS-CoV-2 infection leading to the acute inflammatory response and respiratory distress syndrome or multi-organ failure. On the other hand, the effect of immunosuppressive drug therapies can represent a double edge sword on the course of the disease, either by increased susceptibility to and severity of the infection, or by preventing the accelerated inflammatory response induced by the infection. Additionally, the long-term impact of SARS-CoV-2 infection on the host immune system has led to the onset of novel complex clinical manifestations, comprised under the large umbrella of "long-COVID", which we are only starting to understand. In this review we focus on two interrelated aspects: i) the impact of COVID-19 on patients with pSS and ii) the emerging evidence of long-term xerostomia after SARS-CoV-2 infection.

NKp30 Receptor Upregulation in Salivary Glands of Sjögren's Syndrome Characterizes Ectopic Lymphoid Structures and Is Restricted by Rituximab Treatment.

Primary Sjögren's syndrome (pSS) is a chronic autoimmune disease resulting from the inflammatory infiltration of exocrine glands, mainly salivary and lacrimal glands, leading to secretory dysfunction and serious complications including debilitating fatigue, systemic autoimmunity, and lymphoma. Like other autoimmune disorders, a strong interferon (IFN) signature is present among subsets of pSS patients, suggesting the involvement of innate immunity in pSS pathogenesis. NCR3/NKp30 is a natural killer (NK) cell-specific activating receptor regulating the cross talk between NK and dendritic cells including type II IFN secretion upon NK-cell activation. A genetic association between single-nucleotide polymorphisms (SNPs) in the NCR3/NKp30 promoter gene and a higher susceptibility for pSS has been previously described, with pSS patients most frequently carrying the major allele variant associated with a higher NKp30 transcript and IFN-γ release as a consequence of the receptor engagement. In the present study, we combined RNA-sequencing and histology from pSS salivary gland biopsies to better characterize NKp30 (NCR3) and its ligand B7/H6 (NCR3LG1) in pSS salivary gland tissues. Levels of NCR3/NKp30 were significantly increased both in salivary glands and in circulating NK cells of pSS patients compared with sicca controls, especially in salivary glands with organized ectopic lymphoid structures. In line with this observation, a strong correlation between NCR3/NKp30 levels and salivary gland infiltrating immune cells (CD3, CD20) was found. Furthermore, NCR3/NKp30 levels also correlated with higher IFN-γ, Perforin, and Granzyme-B expression in pSS SGs with organized ectopic lymphoid structures, suggesting an activation state of NK cells infiltrating SG tissue. Of note, NKp30+ NK cells accumulated at the border of the inflammatory foci, while the NKp30 ligand, B7/H6, is shown to be expressed mainly by ductal epithelial cells in pSS salivary glands. Finally, immunomodulatory treatment, such as the B-cell depleting agent rituximab, known to reduce the infiltration of immune cells in pSS SGs, prevented the upregulation of NCR3/NKp30 within the glands.

Treatment of COVID-19 with remdesivir in the absence of humoral immunity: a case report.

The response to the coronavirus disease 2019 (COVID-19) pandemic has been hampered by lack of an effective severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) antiviral therapy. Here we report the use of remdesivir in a patient with COVID-19 and the prototypic genetic antibody deficiency X-linked agammaglobulinaemia (XLA). Despite evidence of complement activation and a robust T cell response, the patient developed persistent SARS-CoV-2 pneumonitis, without progressing to multi-organ involvement. This unusual clinical course is consistent with a contribution of antibodies to both viral clearance and progression to severe disease. In the absence of these confounders, we take an experimental medicine approach to examine the in vivo utility of remdesivir. Over two independent courses of treatment, we observe a temporally correlated clinical and virological response, leading to clinical resolution and viral clearance, with no evidence of acquired drug resistance. We therefore provide evidence for the antiviral efficacy of remdesivir in vivo, and its potential benefit in selected patients.

Blocking T cell co-stimulation in primary Sjögren's syndrome: rationale, clinical efficacy and modulation of peripheral and salivary gland biomarkers.

There is accumulating evidence that patients with primary Sjögren's syndrome (pSS) display aberrant CD4+ T cell responses, both in the peripheral compartment and in the inflamed salivary glands. CD4+ T cell abnormalities are also critically associated with B cell hyper activation, one of the hallmarks of disease, which is linked with disease severity and evolution to lymphoma. T cell activation and the cross-talk between T and B cells are tightly regulated by the balance between co-stimulatory pathways, such as the interactions between CD80/CD86:CD28, CD40:CD40L and ICOS:ICOSL, and co-inhibitory signals, including the immunoregulatory CTLA-4 protein. Evidence from patients with pSS as well as data from animal models of the disease suggests that these pathways play a critical role in pSS pathogenesis and their targeting could be exploited for therapeutic purposes. In this review, we first summarise the evidence implicating aberrant T cell co-stimulation and co-inhibition in driving the disease before focusing on the results of recent randomised controlled trials (RCTs) with compounds able to block T cell co-stimulation and enhance T cell co-inhibition. Despite a clear biological effect on downstream B cell activation has been observed in patients treated with CTLA-4-Ig (abatacept) and with monoclonal antibodies targeting CD40 and ICOSL, the clinical efficacy of this approach has so far yielded mixed results; while the anti-CD40 monoclonal antibody iscalimab showed significant improvement in systemic disease activity compared to placebo, two large RCTs with abatacept and a phase IIa RCT with an anti-ICOSL monoclonal antibody (prezalumab) failed to reach their primary endpoints. Although the discrepancies between biological and clinical efficacy of targeting T cell co-stimulation on pSS remain unresolved, several factors including drug bioavailability and receptor occupancy, patient stratification based on T-cell related biomarkers and the choice of study outcome are likely to play an important role and form the basis for further work towards the quest for a disease-modifying biologic therapy in pSS.

Publisher Correction: Whole-genome sequencing of a sporadic primary immunodeficiency cohort.

An amendment to this paper has been published and can be accessed via a link at the top of the paper.

Whole-genome sequencing of a sporadic primary immunodeficiency cohort.

Primary immunodeficiency (PID) is characterized by recurrent and often life-threatening infections, autoimmunity and cancer, and it poses major diagnostic and therapeutic challenges. Although the most severe forms of PID are identified in early childhood, most patients present in adulthood, typically with no apparent family history and a variable clinical phenotype of widespread immune dysregulation: about 25% of patients have autoimmune disease, allergy is prevalent and up to 10% develop lymphoid malignancies1-3. Consequently, in sporadic (or non-familial) PID genetic diagnosis is difficult and the role of genetics is not well defined. Here we address these challenges by performing whole-genome sequencing in a large PID cohort of 1,318 participants. An analysis of the coding regions of the genome in 886 index cases of PID found that disease-causing mutations in known genes that are implicated in monogenic PID occurred in 10.3% of these patients, and a Bayesian approach (BeviMed4) identified multiple new candidate PID-associated genes, including IVNS1ABP. We also examined the noncoding genome, and found deletions in regulatory regions that contribute to disease causation. In addition, we used a genome-wide association study to identify loci that are associated with PID, and found evidence for the colocalization of-and interplay between-novel high-penetrance monogenic variants and common variants (at the PTPN2 and SOCS1 loci). This begins to explain the contribution of common variants to the variable penetrance and phenotypic complexity that are observed in PID. Thus, using a cohort-based whole-genome-sequencing approach in the diagnosis of PID can increase diagnostic yield and further our understanding of the key pathways that influence immune responsiveness in humans.