Targeted Proteomics Reveals Inflammatory Pathways that Classify Immune Dysregulation in Common Variable Immunodeficiency

The biological basis for current treatment strategies for granulomatous disease in common variable immunodeficiency

PURPOSE OF REVIEW

The pathogenesis of granulomatous disease in common variable immunodeficiency (CVID) is still largely unknown, which hampers effective treatment. This review describes the current knowledge on the pathogenesis of granuloma formation in CVID and the biological basis of the current treatment options.

RECENT FINDINGS

Histological analysis shows that T and B cells are abundantly present in the granulomas that are less well organized and are frequently associated with lymphoid hyperplasia. Increased presence of activation markers such as soluble IL-2 receptor (sIL-2R) and IFN-ɣ, suggest increased Th1-cell activity. Moreover, B-cell abnormalities are prominent in CVID, with elevated IgM, BAFF, and CD21low B cells correlating with granulomatous disease progression. Innate immune alterations, as M2 macrophages and neutrophil dysregulation, indicate chronic inflammation. Therapeutic regimens include glucocorticoids, DMARDs, and biologicals like rituximab.

SUMMARY

Our review links the biological context of CVID with granulomatous disease or GLILD to currently prescribed therapies and potential targeted treatments.

The impact of immune dysregulation on the risk of malignancy in common variable immunodeficiency: insights from a multicenter study

Background

Common Variable Immunodeficiency (CVID) represents a heterogenic group of primary immunodeficiencies (PID) characterized by impaired antibody production and susceptibility to infections. Non-infectious complications, such as autoimmune diseases, lymphoproliferative disorders, and malignancies, now significantly impact prognosis. Moreover, both hematologic and solid organ malignancies are more frequently observed in CVID patients compared to other PIDs. The risk factors for carcinogenesis in CVID remain largely unknown.

Objective

This multicenter study aims to characterize the clinical profile of cancer in CVID patients in Spain and to identify independent risk factors associated with malignancy development, focusing on the role of immune dysregulation.

Methods

A nationwide, cross-sectional study was conducted from November 2019 to May 2022, involving 17 hospitals treating PID patients in Spain. Data were collected systematically on demographics, infectious and non-infectious comorbidities, immunological parameters, and treatment. Statistical analysis, including multivariate logistic regression, was performed to identify risk factors associated to malignancy.

Results

Of 250 CVID patients, 38 (15.26%) were diagnosed with cancer, predominantly non-Hodgkin lymphoma, gastric cancer, and lung adenocarcinoma. Cancer patients were significantly older (mean age 60.70 vs. 49.36 years, p<0.001) and had higher rates of immune dysregulation (81.58% vs. 59.7%, p=0.01). Immune dysregulation was an independent risk factor for cancer (OR 2.19, p=0.04), alongside previous immunosuppressant therapy (OR 2, p=0.031), higher IgM levels (OR 1.008 per SD, p=0.012), older age (OR 1.04, p<0.001), and lower CD4 cell counts at diagnosis (OR 0.997, p<0.001).

Conclusions

This study highlights the increased cancer risk in CVID patients, with immune dysregulation, prior immunosuppressant use, elevated IgM levels, and lower CD4 cell counts as conjointly associated. These findings underscore the need for vigilant cancer screening and tailored management strategies in CVID patients to improve outcomes. Future research should focus on elucidating the molecular mechanisms linking immune dysregulation and malignancy in CVID.

Decoding mutational hotspots in human disease through the gene modules governing thymic regulatory T cells

Computational strategies to extract meaningful biological information from multiomics data are in great demand for effective clinical use, particularly in complex immune-mediated disorders. Regulatory T cells (Tregs) are essential for immune homeostasis and self-tolerance, controlling inflammatory and autoimmune processes in many diseases with a multigenic basis. Here, we quantify the Transcription Factor (TF) differential occupancy landscape to uncover the Gene Regulatory Modules governing lineage-committed Tregs in the human thymus, and show that it can be used as a tool to prioritise variants in complex diseases. We combined RNA-seq and ATAC-seq and generated a matrix of differential TF binding to genes differentially expressed in Tregs, in contrast to their counterpart conventional CD4 single-positive thymocytes. The gene loci of both established and novel genetic interactions uncovered by the Gene Regulatory Modules were significantly enriched in rare variants carried by patients with common variable immunodeficiency, here used as a model of polygenic-based disease with severe inflammatory and autoimmune manifestations. The Gene Regulatory Modules controlling the Treg signature can, therefore, be a valuable resource for variant classification, and to uncover new therapeutic targets. Overall, our strategy can also be applied in other biological processes of interest to decipher mutational hotspots in individual genomes.

Granulomas in Common Variable Immunodeficiency Display Different Histopathological Features Compared to Other Granulomatous Diseases

Granulomatous disease affects up to 20% of patients with Common Variable Immunodeficiency (CVID). Granulomas are comprised of highly activated immune cells, and emerge in response to antigenic triggers. In CVID granulomas however, the underlying pathophysiology is unclear and the specific trigger remains unknown. Granuloma formation in CVID is often compared to sarcoidosis, although clinical context and prognosis differ, suggesting a different pathogenesis. The aim of this study was to investigate if the cellular organization and proteomics of granulomas in CVID is different from other granulomatous diseases. Therefore, tissue slides from formaldehyde fixed paraffin embedded biopsies obtained from patients with CVID, sarcoidosis, tuberculosis and foreign-material induced pseudo-sarcoidosis were stained with hematoxylin and eosin and assessed for histopathological characteristics. Targeted spatial protein analysis was performed, and immune fluorescent multiplex assays were used to analyze the cellular organization. Histological analysis revealed that CVID granulomas were smaller, less circumscribed, with fewer multinucleated giant cells and minimal fibrosis compared to the other granulomatous diseases. Spatial protein analysis showed that granulomas in all diseases expressed CD68, CD11c, CD44, CD127, and PD-L1. However in CVID, reduced expression of the fibrosis-related protein fibronectin, but enrichment of CD163, CD3 and FAPα inside CVID granulomas was observed. Immunofluorescence analysis conformed a different cellular organization in CVID granulomas with increased influx of neutrophils, macrophages, T and B lymphocytes. In conclusion, granulomas in CVID display a different histological and cellular organization with increased influx of myeloid and lymphoid cells, compared to sarcoidosis, tuberculosis and pseudo-sarcoidosis, indicating a distinct pathogenesis underlying granuloma formation.

Comparison of Post-Vaccination Cellular Immune Response in Patients with Common Variable Immune Deficiency

BACKGROUND

The problem of identifying vaccine-specific T-cell responses is still a matter of debate. Currently, there are no universal, clearly defined, agreed upon criteria for assessing the effectiveness of vaccinations and their immunogenicity for the cellular component of immunity, even for healthy people. But for patients with inborn errors of immunity (IEI), especially those with antibody deficiencies, evaluating cellular immunity holds significant importance.

AIM

To examine the effect of one and two doses of inactivated adjuvanted subunit influenza vaccines on the expression of endosomal Toll-like receptors (TLRs) on the immune cells and the primary lymphocyte subpopulations in patients with common variable immunodeficiency (CVID).

MATERIALS AND METHODS

During 2018-2019, six CVID patients received one dose of a quadrivalent adjuvanted influenza vaccine; in 2019-2020, nine patients were vaccinated with two doses of a trivalent inactivated influenza vaccine. The proportion of key lymphocyte subpopulations and expression levels of TLRs were analyzed using flow cytometry with monoclonal antibodies.

RESULTS

No statistically significant alterations in the absolute values of the main lymphocyte subpopulations were observed in CVID patients before or after vaccination with the different immunization protocols. However, after vaccination, a higher expression of TLR3 and TLR9 in granulocytes, monocytes, and lymphocytes was found in those patients who received two vaccine doses rather than one single dose.

CONCLUSION

This study marks the first instance of using a simultaneous two-dose vaccination, which is associated with an elevated level of TLR expression in the immune cells. Administration of the adjuvanted vaccines in CVID patients appears promising. Further research into their impact on innate immunity and the development of more effective vaccination regimens is warranted.

Sarcoidosis versus Granulomatous and Lymphocytic Interstitial Lung Disease in Common Variable Immunodeficiency: A Comparative Review

Sarcoidosis and Granulomatous and Lymphocytic Interstitial Lung Diseases (GLILD) are two rare entities primarily characterised by the development of Interstitial Lung Disease (ILD) in the context of systemic immune dysregulation. These two conditions partially share the immunological background and pathologic findings, with granuloma as the main common feature. In this narrative review, we performed a careful comparison between sarcoidosis and GLILD, with an overview of their main similarities and differences, starting from a clinical perspective and ending with a deeper look at the immunopathogenesis and possible target therapies. Sarcoidosis occurs in immunocompetent individuals, whereas GLILD occurs in patients affected by common variable immunodeficiency (CVID). Moreover, peculiar extrapulmonary manifestations and radiological and histological features may help distinguish the two diseases. Despite that, common pathogenetic pathways have been suggested and both these disorders can cause progressive impairment of lung function and variable systemic granulomatous and non-granulomatous complications, leading to significant morbidity, reduced quality of life, and survival. Due to the rarity of these conditions and the extreme clinical variability, there are still many open questions concerning their pathogenesis, natural history, and optimal management. However, if studied in parallel, these two entities might benefit from each other, leading to a better understanding of their pathogenesis and to more tailored treatment approaches.

Computational approaches for clinical, genomic and proteomic markers of response to glucagon-like peptide-1 therapy in type-2 diabetes mellitus: An exploratory analysis with machine learning algorithms

INTRODUCTION

In 2021, the International Diabetes Federation reported that 537 million people worldwide are living with diabetes. While glucagon-like peptide-1 agonists provide significant benefits in diabetes management, approximately 40% of patients do not respond well to this therapy. This study aims to enhance treatment outcomes by using machine learning to predict individual response status to glucagon-like peptide-1 therapy.

METHODS

We analysed a type-2 diabetes mellitus dataset from the Diastrat cohort, recruited at the Northern Ireland Centre for Stratified Medicine. The dataset included individuals prescribed glucagon-like peptide-1 therapy, with response status determined by glycated haemoglobin levels of ≤53 mmol/mol. We identified genomic and proteomic markers and developed machine learning models to predict therapy response.

RESULTS

The study found 5 genomic variants and 45 proteomic markers that help differentiate glucagon-like peptide-1 therapy responders from non-responders, achieving 95 % prediction accuracy with a machine learning model.

CONCLUSION

This study demonstrates the potential of machine learning in predicting the response to glucagon-like peptide-1 therapy in individuals with type-2 diabetes mellitus. These findings suggest that integrating genomic and proteomic data can significantly enhance personalized treatment approaches, potentially improving outcomes for patients who might otherwise not respond well to glucagon-like peptide-1 therapy. Further research and validation in larger cohorts are necessary to confirm these results and translate them into clinical practice.

Exploring metformin monotherapy response in Type-2 diabetes: Computational insights through clinical, genomic, and proteomic markers using machine learning algorithms

BACKGROUND

In 2016, the UK had 4.5 million people with diabetes, predominantly Type-2 Diabetes Mellitus (T2DM). The NHS allocates £10 billion (9% of its budget) to manage diabetes. Metformin is the primary treatment for T2DM, but 35% of patients don't benefit from it, leading to complications. This study aims to delve into metformin's efficacy using clinical, genomic, and proteomic data to uncover new biomarkers and build a Machine Learning predictor for early metformin response detection.

METHODS

Here we report analysis from a T2DM dataset of individuals prescribed metformin monotherapy from the Diastrat cohort recruited at the Altnagelvin Area Hospital, Northern Ireland.

RESULTS

In the clinical data analysis, comparing responders (those achieving HbA1c ≤ 48 mmol/mol) to non-responders (with HbA1c > 48 mmol/mol), we identified that creatinine levels and bodyweight were more negatively correlated with response than non-response. In genomic analysis, we identified statistically significant (p-value <0.05) variants rs6551649 (LPHN3), rs6551654 (LPHN3), rs4495065 (LPHN3) and rs7940817 (TRPC6) which appear to differentiate the responders and non-responders. In proteomic analysis, we identified 15 statistically significant (p-value <0.05, q-value <0.05) proteomic markers that differentiate controls, responders, non-responders and treatment groups, out of which the most significant were HAOX1, CCL17 and PAI that had fold change ∼2. A machine learning model was build; the best model predicted non-responders with 83% classification accuracy.

CONCLUSION

Further testing in prospective validation cohorts is required to determine the clinical utility of the proposed model.

Bone Mineral Density is Related to CD4+ T Cell Counts and Muscle Mass is Associated with B Cells in Common Variable Immunodeficiency Patients

BACKGROUND

Common variable immunodeficiency (CVID) is a primary immunodeficiency characterized by chronic/recurrent respiratory infections, bronchiectasis, autoimmunity, inflammatory, gastrointestinal diseases and malignancies associated with a chronic inflammatory state and increased risk of osteoporosis and muscle loss.

AIM

The aim of this study was to evaluate bone mineral density (BMD), body composition and their relationship with lymphocyte subpopulations in CVID patients.

METHODS

Dual-energy X-ray absorptiometry was performed to assess BMD, lean mass, and fat mass in CVID patients. Peripheral blood CD4+, CD8+, and CD19+ cells were measured using flow cytometry.

RESULTS

Thirty-three patients (37.3 ± 10.8 years old) were examined. Although only 11.8% of the individuals were malnourished (BMI <18.5 kg/m2), 27.7% of them had low skeletal muscle mass index (SMI), and 57.6% of them had low BMD. Patients with osteopenia/osteoporosis presented lower weight (p = 0.007), lean mass (p = 0.011), appendicular lean mass (p = 0.011), SMI (p = 0.017), and CD4+ count (p = 0.030). Regression models showed a positive association between CD4+ count and bone/muscle parameters, whereas CD19+ B cell count was only associated with muscle variables. Analysis of ROC curves indicated a cutoff value of CD4+ count (657 cells/mm3; AUC: 0.71, 95% CI 0.52-0.90) which was related to low BMD. Weight (p = 0.004), lean mass (p = 0.027), appendicular lean mass (p = 0.022), SMI (p = 0.029), total bone mineral content (p = 0.005), lumbar (p = 0.005), femoral neck (p = 0.035), and total hip BMD (p<0.001) were found to be lower in patients with CD4+ count below the cutoff.

CONCLUSION

CVID patients presented with low BMD, which was associated with CD4+ count. Moreover, low muscle parameters were correlated with B cell count.

Plasma Levels of mir-34a-5p Correlate with Systemic Inflammation and Low Naïve CD4 T Cells in Common Variable Immunodeficiency

PURPOSE

Common variable immunodeficiency (CVID) is a primary antibody deficiency that commonly manifests as recurrent infections. Many CVID patients also suffer from immune dysregulation, an inflammatory condition characterized by polyclonal lymphocytic tissue infiltration and associated with increased morbidity and mortality. The genetic cause is unknown in most CVID patients and epigenetic alterations may contribute to the broad range of clinical manifestations. MicroRNAs are small non-coding RNAs that are involved in epigenetic modulation and may contribute to the clinical phenotype in CVID.

METHODS

Here, we determined the circulating microRNAome and plasma inflammatory proteins of a cohort of CVID patients with various levels of immune dysregulation and compared them to healthy controls. A set of deregulated microRNAs was validated by qPCR and correlated to inflammatory proteins and clinical findings.

RESULTS

Levels of microRNA-34a correlated with 11 proteins such as CXCL9, TNF, and IL10, which were predicted to be biologically connected. Moreover, there was a negative correlation between mir-34 levels and the number of naïve CD4 T cells in CVID.

CONCLUSION

Collectively, our data show that microRNAs correlate with the inflammatory response in CVID. Further investigations are needed to elucidate the role of miRNAs in the development of CVID-related immune dysregulation.

In-depth immune profiling reveals advanced B- and T-cell differentiation to be associated with Th1-driven immune dysregulation in common variable immunodeficiency

Common variable immunodeficiency (CVID) is an inborn error of immunity characterized by low levels of antibodies. In addition to infections, many patients also suffer from T-helper 1-driven immune dysregulation, which is associated with increased mortality. The aim of this study was to perform in-depth characterization of the T and the B cell compartments in a well-defined cohort of patients affected by CVID and correlate the findings to the level of clinical immune dysregulation. We used mass cytometry, targeted proteomics, flow cytometry and functional assays to delineate the immunological phenotype of 15 CVID-affected patients with different levels of immune dysregulation. Unbiased clustering of T cell mass cytometry data correlated with CVID-related immune dysregulation and plasma protein profiles. Expanded CXCR3+ T-bet-expressing B cells correlated with effector memory CD4+ T cell clusters, and increased plasma levels of CXCR3-ligands. Our findings indicate an interplay between B cells and T cells in CVID-related immune dysregulation and provide a better understanding of the underlying pathological mechanisms.

Cytokine dysregulation despite immunoglobulin replacement therapy in common variable immunodeficiency (CVID)

Introduction

Common variable immunodeficiency (CVID) is the most prevalent symptomatic primary immunodeficiency. CVID is a heterogeneous disorder with a presumed multifactorial etiology. Intravenous or subcutaneous immunoglobulin replacement therapy (IgRT) can prevent severe infections but not underlying immune dysregulation.

Methods

In this study, we evaluated the serum concentrations of proinflammatory (TNF-α, IL-1β, IL-6) and immunoregulatory cytokines (IL-10), as well as lipopolysaccharide (LPS) and soluble CD14 (sCD14) in CVID individuals with infectious only (INF-CVID), and those with additional systemic autoimmune and inflammatory disorders (NIC-CVID), and healthy donors (HD).

Results

Our results showed increased serum concentrations of TNF-α, IL-1β, IL-6, and IL-10 in both INF-CVID and NIC-CVID subjects compared to HD. However, elevations of TNF-α, IL-1β, IL-6, and IL-10 were significantly more marked in NIC-CVID than INF-CVID. Additionally, LPS concentrations were increased only in NIC-CVID but not in INF-CVID compared to HD. Circulating levels of sCD14 were significantly increased in NIC-CVID compared to both INF-CVID and HD.

Discussion

These findings indicate persistent cytokine dysregulation despite IgRT in individuals with CVID. Moreover, the circulating cytokine profile reveals the heterogeneity of immune dysregulation in different subgroups of CVID subjects.

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.

Dysregulated Lymphocyte Antigen Receptor Signaling in Common Variable Immunodeficiency with Granulomatous Lymphocytic Interstitial Lung Disease

PURPOSE

A subset of common variable immunodeficiency (CVID) patients either presents with or develops autoimmune and lymphoproliferative complications, such as granulomatous lymphocytic interstitial lung disease (GLILD), a major cause of morbidity and mortality in CVID. While a myriad of phenotypic lymphocyte derangements has been associated with and described in GLILD, defects in T and B cell antigen receptor (TCR/BCR) signaling in CVID and CVID with GLILD (CVID/GLILD) remain undefined, hindering discovery of biomarkers for disease monitoring, prognostic prediction, and personalized medicine approaches.

METHODS

To identify perturbations of immune cell subsets and TCR/BCR signal transduction, we applied mass cytometry analysis to peripheral blood mononuclear cells (PBMCs) from healthy control participants (HC), CVID, and CVID/GLILD patients.

RESULTS

Patients with CVID, regardless of GLILD status, had increased frequency of HLADR+CD4+ T cells, CD57+CD8+ T cells, and CD21lo B cells when compared to healthy controls. Within these cellular populations in CVID/GLILD patients only, engagement of T or B cell antigen receptors resulted in discordant downstream signaling responses compared to CVID. In CVID/GLILD patients, CD21lo B cells showed perturbed BCR-mediated phospholipase C gamma and extracellular signal-regulated kinase activation, while HLADR+CD4+ T cells and CD57+CD8+ T cells displayed disrupted TCR-mediated activation of kinases most proximal to the receptor.

CONCLUSION

Both CVID and CVID/GLILD patients demonstrate an activated T and B cell phenotype compared to HC. However, only CVID/GLILD patients exhibit altered TCR/BCR signaling in the activated lymphocyte subsets. These findings contribute to our understanding of the mechanisms of immune dysregulation in CVID with GLILD.

Microneedle Patch for Painless Intradermal Collection of Interstitial Fluid Enabling Multianalyte Measurement of Small Molecules, SARS-CoV-2 Antibodies, and Protein Profiling

Blood sampling is a common practice to monitor health, but it entails a series of drawbacks for patients including pain and discomfort. Thus, there is a demand for more convenient ways to obtain samples. Modern analytical techniques enable monitoring of multiple bioanalytes in smaller samples, opening possibilities for new matrices, and microsampling technologies to be adopted. Interstitial fluid (ISF) is an attractive alternative matrix that shows good correlation with plasma concentration dynamics for several analytes and can be sampled in a minimally invasive and painless manner from the skin at the point-of-care. However, there is currently a lack of sampling devices compatible with clinical translation. Here, to tackle state-of-the-art limitations, a cost-effective and compact single-microneedle-based device designed to painlessly collect precisely 1.1 µL of dermal ISF within minutes is presented. The fluid is volume-metered, dried, and stably stored into analytical-grade paper within the microfluidic device. The obtained sample can be mailed to a laboratory, quantitatively analyzed, and provide molecular insights comparable to blood testing. In a human study, the possibility to monitor various classes of molecular analytes is demonstrated in ISF microsamples, including caffeine, hundreds of proteins, and SARS-CoV-2 antibodies, some being detected in ISF for the first time.

Common Variable Immunodeficiency: More Pathways than Roads to Rome

Fifty years have elapsed since the term common variable immunodeficiency (CVID) was introduced to accommodate the many and varied antibody deficiencies being identified in patients with suspected inborn errors of immunity (IEIs). Since then, how the term is understood and applied for diagnosis and management has undergone many revisions, though controversy persists on how exactly to define and classify CVID. Many monogenic disorders have been added under its aegis, while investigations into polygenic, epigenetic, and somatic contributions to CVID susceptibility have gained momentum. Expansion of the overall IEI landscape has increasingly revealed genotypic and phenotypic overlap between CVID and various other immunological conditions, while increasingly routine genotyping of CVID patients continues to identify an incredible diversity of pathophysiological mechanisms affecting even single genes. Though many questions remain to be answered, the lessons we have already learned from CVID biology have greatly informed our understanding of adaptive, but also innate, immunity.

Raised Serum Markers of T Cell Activation and Exhaustion in Granulomatous-Lymphocytic Interstitial Lung Disease in Common Variable Immunodeficiency

Purpose

About 20–30% of patients with common variable immunodeficiency (CVID) develop granulomatous-lymphocytic interstitial lung disease (GLILD) as one of several non-infectious complications to their immunodeficiency. The purpose of this study was to identify biomarkers that could distinguish GLILD from other non-infectious complications in CVID.

Methods

We analyzed serum biomarkers related to inflammation, pulmonary epithelium injury, fibrogenesis, and extracellular matrix (ECM) remodeling, and compared three subgroups of CVID: GLILD patients (n = 16), patients with other non-infectious complications (n = 37), and patients with infections only (n = 20).

Results

We found that GLILD patients had higher levels of sCD25, sTIM-3, IFN-γ, and TNF, reflecting T cell activation and exhaustion, compared to both CVID patients with other inflammatory complications and CVID with infections only. GLILD patients also had higher levels of SP-D and CC16, proteins related to pulmonary epithelium injury, as well as the ECM remodeling marker MMP-7, than patients with other non-infectious complications.

Conclusion

GLILD patients have elevated serum markers of T cell activation and exhaustion, pulmonary epithelium injury, and ECM remodeling, pointing to potentially important pathways in GLILD pathogenesis, novel targets for therapy, and promising biomarkers for clinical evaluation of these patients.

Supplementary Information

The online version contains supplementary material available at 10.1007/s10875-022-01318-1.

Bronchial inflammation biomarker patterns link humoral immunodeficiency with bronchiectasis-related small airway dysfunction

BACKGROUND

The progression of chronic destructive lung disease in patients with humoral immunodeficiency (ID) and concomitant development of bronchiectasis is difficult to prevent. Lung function tests in these patients typically show bronchial obstruction of the small airways in combination with increased air trapping in the distal airways, which is consistent with small airway dysfunction.

OBJECTIVE

The objective was to assess the grade of chronic lower airway inflammation and small airway dysfunction from induced sputum and the corresponding local pro-inflammatory mediator pattern to discriminate patients affected by bronchiectasis-related Small Airway Dysfunction (SAD).

METHODS

In a prospective design, 22 patients with ID (14 CVID, 3 XLA, 3 hyper-IgM syndrome, 1 hyper-IgE syndrome and low IgG levels due to treatment with rituximab and 1 SCID after BMT and persistent humoral defect) and 21 healthy controls were examined. Lung function, Fraction Expiratory Nitric Oxide (FeNO) and pro-inflammatory cytokine levels were compared in subsets of patients with (ID + BE) and without bronchiectasis (ID) pre-stratified using high-resolution computed tomography (HRCT) scans and control subjects.

RESULTS

Analysis of induced sputum showed significantly increased total cell counts and severe neutrophilic inflammation in ID. The concomitant SAD revealed higher total cell numbers compared to ID. Bronchial inflammation in ID is clearly mirrored by pro-inflammatory mediators IL-1β, IL-6 and CXCL-8, whilst TNF-α revealed a correlation with lung function parameters altered in the context of bronchiectasis-related Small Airway Dysfunction.

CONCLUSIONS

In spite of immunoglobulin substitution, bronchial inflammation was dominated by neutrophils and was highly increased in patients with ID + BE. Notably, the pro-inflammatory cytokines in patients with ID were significantly increased in induced sputum. The context-dependent cytokine pattern in relation to the presence of concomitant bronchiectasis associated with SAD in ID patients could be helpful in delimiting ID patient subgroups and individualizing therapeutic approaches.

Contribution of Helicobacter pylori to the Inflammatory Complications of Common Variable Immunodeficiency

Common Variable Immunodeficiency (CVID), the most prevalent symptomatic primary immunodeficiency, is frequently associated with severe inflammatory complications that determine its morbidity and mortality. We hypothesize that Helicobacter pylori (HP), a very common worldwide infection, may contribute to the clinical and immune phenotype of CVID. We stratified 41 CVID patients into HP+ (n=26) and HPneg (n=15) groups, according to previous urease breath test and/or gastric biopsies, and compared their clinical manifestations and immune profile evaluated by flow cytometry. No genetic variants with known potential impact in HP infection were found upon WES/WGS. Gastric complications were significantly more frequent in HP+ patients. Importantly, the six CVID patients with gastric cancer were infected with HP. In contrast, a significantly higher frequency of cytopenias was observed in the HPneg. Moreover, HP+ did not feature higher prevalence of organ auto-immunity, as well as of lung, liver or intestinal inflammatory manifestations. We observed the same B-cell profiles in HP+ and HPneg groups, accompanied by marked CD4 and CD8 T-cell activation, increased IFNγ production, and contraction of naïve compartments. Notably, HP+ patients featured low CD25 despite preserved Foxp3 levels in CD4 T cells. Overall, HP impact in CVID inflammatory complications was mainly restricted to the gastric mucosa, contributing to increased incidence of early onset gastric cancer. Thus, early HP screening and eradication should be performed in all CVID patients irrespective of symptoms.

Seeking Relevant Biomarkers in Common Variable Immunodeficiency

Common variable immunodeficiency (CVID) is the most common symptomatic form of primary immunodeficiency. More than 50% of patients in some series suffer from autoimmune or inflammatory complications (the "CVID+" phenotype), and these are not adequately addressed by current treatments. Despite major advancements in genetics, the pathogenesis of the CVID+ phenotype has remained unexplained for most patients, necessitating the need for relevant biomarkers in both the clinic and research settings. In the clinics, reduced isotype-switched memory B cells (≤ 0.55% of B cells) and reduced T cells (CD4) can be utilized to identify those with increased complication risks. Additionally, condition-specific markers have also been suggested for lymphoma (normal or elevated IgM) and progressive interstitial lung disease (increased BAFF, normal or elevated IgM). Additional biomarkers have provided insights into disease pathogenesis, demonstrating wider systemic inflammation (increased LBP, sCD14, and sCD25; expanded ILC3), mucosal defects (increased zonulin, I-FABP), and perhaps reduced anti-inflammatory capability (reduced HDL) in CVID. Most recently, efforts have revealed elevated circulating bioactive bacterial DNA levels - marking microbial translocation and potentially linking the causation of multiple inflammatory changes previously observed in CVID. The implementation of high throughput profiling techniques may accelerate the search of relevant biomarker profiles in CVID and lead to better clinical risk stratification, revealing disease insights, and identifying potential therapeutic targets.

Clinical features and immune-related protein patterns of anti-MDA5 positive clinically amyopathic dermatomyositis Dutch patients

OBJECTIVES

The presence of melanoma differentiation-associated protein 5 (MDA5) antibodies in patients with dermatomyositis (DM) is associated with the development of a rapidly progressive interstitial lung disease (RPILD), unresponsive to conventional treatment. We characterize patients and provide more insight into potential biomarkers to identify patients with RPILD.

METHODS

Patients diagnosed with anti-MDA5 positive DM between December 2015 and November 2017 were included in this study. Clinical data were retrospectively retrieved from medical records. 180 immune-related markers were measured in sera of 16 patients and 15 healthy controls using proximity extension assay based technology.

RESULTS

Twenty patients were included, with a median time from symptoms till diagnosis of 4 months. All patients had clinically amyopathic DM. Interstitial lung disease (ILD) was present at diagnosis in 94% of the patients, 45% presented with RPILD. The mortality rate was 35% within 4 months after diagnosis and respiratory failure was the main cause of death in these patients. Furthermore, unsupervised analysis revealed that patients with RPILD show clearly different inflammatory serum profiles than healthy controls. In addition, in comparison to healthy controls, the interferon, Interleukin (IL)1, IL10 and IL18 signalling pathways are different regulated in anti-MDA5 positive patients.

CONCLUSION

In this Dutch anti-MDA5 positive CADM cohort, one third of the patients died due to RPILD soon after diagnosis, which underlines the severity of this disease. In addition, we have found several possible pathways that are differentially regulated in RPILD vs no RPILD DM and healthy controls. These markers await further validation before clinical use.

Chronically Activated T-cells Retain Their Inflammatory Properties in Common Variable Immunodeficiency

Purpose

Immune dysregulation complications cause significant morbidity and mortality in common variable immunodeficiency (CVID), but the underlying pathophysiology is poorly understood. While CVID is primarily considered a B-cell defect, resulting in the characteristic hypogammaglobulinemia, T-cells may also contribute to immune dysregulation complications. Here, we aim to further characterize T-cell activation and regulation in CVID with immune dysregulation (CVIDid).

Methods

Flow cytometry was performed to investigate T-cell differentiation, activation and intracellular cytokine production, negative regulators of immune activation, regulatory T-cells (Treg), and homing markers in 12 healthy controls, 12 CVID patients with infections only (CVIDio), and 20 CVIDid patients.

Results

Both CD4 + and CD8 + T-cells in CVIDid showed an increased activation profile (HLA-DR + , Ki67 + , IFNγ +) when compared to CVIDio, with concomitant upregulation of negative regulators of immune activation PD1, LAG3, CTLA4, and TIGIT. PD1 + and LAG3 + subpopulations contained equal or increased frequencies of cells with the capacity to produce IFNγ, Ki67, and/or GzmB. The expression of PD1 correlated with serum levels of CXCL9, 10, and 11. Treg frequencies were normal to high in CVIDid, but CVIDid Tregs had reduced CTLA-4 expression, especially on CD27 + effector Tregs. Increased migratory capacity to inflamed and mucosal tissue was also observed in CVIDid T-cells.

Conclusion

CVIDid was characterized by chronic activation of peripheral T-cells with preserved inflammatory potential rather than functional exhaustion, and increased tissue migratory capacity. While Treg numbers were normal in CVIDid Tregs, low levels of CTLA-4 indicate possible Treg dysfunction. Combined studies of T-cell dysfunction and circulating inflammatory proteins may direct future treatment strategies.

Supplementary Information

The online version contains supplementary material available at 10.1007/s10875-021-01084-6.

Gut Microbiota-Host Interactions in Inborn Errors of Immunity

Inborn errors of immunity (IEI) are a group of disorders that are mostly caused by genetic mutations affecting immune host defense and immune regulation. Although IEI present with a wide spectrum of clinical features, in about one third of them various degrees of gastrointestinal (GI) involvement have been described and for some IEI the GI manifestations represent the main and peculiar clinical feature. The microbiome plays critical roles in the education and function of the host's innate and adaptive immune system, and imbalances in microbiota-immunity interactions can contribute to intestinal pathogenesis. Microbial dysbiosis combined to the impairment of immunosurveillance and immune dysfunction in IEI, may favor mucosal permeability and lead to inflammation. Here we review how immune homeostasis between commensals and the host is established in the gut, and how these mechanisms can be disrupted in the context of primary immunodeficiencies. Additionally, we highlight key aspects of the first studies on gut microbiome in patients affected by IEI and discuss how gut microbiome could be harnessed as a therapeutic approach in these diseases.