Challenges for gene editing in common variable immunodeficiency disorders: Current and future prospects.

The original CRISPR Cas9 gene editing system and subsequent innovations offers unprecedented opportunities to correct severe genetic defects including those causing Primary Immunodeficiencies (PIDs). Common Variable Immunodeficiency Disorders (CVID) are the most frequent symptomatic PID in adults and children. Unlike many other PIDs, patients meeting CVID criteria do not have a definable genetic defect and cannot be considered to have an inborn error of immunity (IEI). Patients with a CVID phenotype carrying a causative mutation are deemed to have a CVID-like disorder consequent to an IEI. Patients from consanguineous families often have highly penetrant early-onset autosomal recessive forms of CVID-like disorders. Individuals from non-consanguineous families may have autosomal dominant CVID-like disorders with variable penetrance and expressivity. This essay explores the potential clinical utility as well as the current limitations and risks of gene editing including collateral genotoxicity. In the immediate future the main application of this technology is likely to be the in vitro investigation of epigenetic and polygenic mechanisms, which are likely to underlie many cases of CVID and CVID-like disorders. In the longer-term, the CRISPR Cas9 system and other gene-based therapies could be utilized to treat CVID-like disorders, where the underlying IEI is known.

Relationships between bronchiectasis and time to achieving target trough immunoglobulin G levels in patients with common variable immunodeficiency.

Background: The main treatment of common variable immunodeficiency (CVID) is to maintain immunoglobulin G (IgG) levels within the target range. However, trough IgG levels differ among patients with similar body mass index (BMI) and those receiving the same dose of immunoglobulin replacement therapy (IGRT). A crucial factor that underlies these differences is the presence of extensive bronchiectasis, which is associated with the immunoglobulin salvage pathway. Objective: We compared trough IgG levels in patients with CVID and with and in those without bronchiectasis who had received the same dose of IGRT for 2 years to determine the association of IgG level with infection frequency. Method: This retrospective cohort study included 61 patients with CVID, of whom 21 had bronchiectasis. We reviewed the electronic records for demographic variables, baseline immunoglobulin levels, mean trough IgG levels over 2 years, efficacy levels (trough IgG level - baseline IgG level), the time interval from treatment initiation to achieving the target trough IgG level (700 mg/dL), and the number of infections. Results: The median age of the patients was 39 years (IQR, 27-51), and 29 were women (47.5%). There were no significant differences between the groups in terms of age, age at diagnosis, delay in diagnosis, sex, BMI, IGRT type (subcutaneous or intravenous), and baseline immunoglobulin levels. Trough IgG and efficacy levels were lower (P < 0.001 and P = 0.016, respectively), the time required to achieve the target IgG level was longer in patients with bronchiectasis than in those without bronchiectasis, and this time interval was significantly associated with the infection frequency. Trough IgG and albumin levels were correlated (p = 0.007), with minor differences between the groups (p = 0.04). Conclusion: Bronchiectasis was significantly associated with a longer time to achieve the target IgG levels. These long-term differences between the patients with and those without bronchiectasis have significant clinical implications.

Impaired B Cell Recall Memory and Reduced Antibody Avidity but Robust T Cell Response in CVID Patients After COVID-19 Vaccination.

PURPOSE: Humoral and cellular immune responses were described after COVID-19 vaccination in patients with common variable immunodeficiency disorder (CVID). This study aimed to investigate SARS-CoV-2-specific antibody quality and memory function of B cell immunity as well as T cell responses after COVID-19 vaccination in seroresponding and non-responding CVID patients. METHODS: We evaluated antibody avidity and applied a memory B cell ELSPOT assay for functional B cell recall memory response to SARS-CoV-2 after COVID-19 vaccination in CVID seroresponders. We comparatively analyzed SARS-CoV-2 spike reactive polyfunctional T cell response and reactive peripheral follicular T helper cells (pTFH) by flow cytometry in seroresponding and non-seroresponding CVID patients. All CVID patients had previously failed to mount a humoral response to pneumococcal conjugate vaccine. RESULTS: SARS-CoV-2 spike antibody avidity of seroresponding CVID patients was significantly lower than in healthy controls. Only 30% of seroresponding CVID patients showed a minimal memory B cell recall response in ELISPOT assay. One hundred percent of CVID seroresponders and 83% of non-seroresponders had a detectable polyfunctional T cell response. Induction of antigen-specific CD4+CD154+CD137+CXCR5+ pTFH cells by the COVID-19 vaccine was higher in CVID seroresponder than in non-seroresponder. Levels of pTFH did not correlate with antibody response or avidity. CONCLUSION: Reduced avidity and significantly impaired recall memory formation after COVID-19 vaccination in seroresponding CVID patients stress the importance of a more differentiated analysis of humoral immune response in CVID patients. Our observations challenge the clinical implications that follow the binary categorization into seroresponder and non-seroresponder.

CVID-Associated Intestinal Disorders in the USIDNET Registry: An Analysis of Disease Manifestations, Functional Status, Comorbidities, and Treatment.

Common variable immunodeficiency (CVID) has been subdivided into five phenotypes, including one marked by non-infectious enteropathies that lead to significant morbidity and mortality. We examined a large national registry of patients with CVID to better characterize this population and understand how the presence of enteropathy influences nutritional status, patient function, and the risk of additional non-infectious disorders in CVID patients. We also sought to illustrate the range of treatment strategies for CVID-associated enteropathies. We extracted patient data from the United States Immunodeficiency Network (USIDNET) database, which included 1415 patients with CVID, and compared those with and without intestinal disorders. Demographic and genetic profiles, functional status, and treatments targeting intestinal disorders are reported. Intestinal disorders were present in 20% of patients with CVID, including chronic diarrhea, inflammatory bowel disease, malabsorption, and others. Compared to those without enteropathies, this patient subset exhibited significantly lower Karnofsky-Lansky functional scores, greater reliance on nutritional support, higher rates of vitamin deficiencies, and increased prevalence of hematologic disorders, liver disease, pulmonary disease, granulomatous disease, and lymphoma. Genetic data were reported for only 5% of the cohort. No mutations segregated significantly to patients with or without intestinal disease. Corticosteroids were most frequently used for treatment. Patients with CVID-associated intestinal disorders exhibit higher rates of autoimmune and inflammatory comorbidities, lymphoma, malnutrition, and debility. We review recent studies implicating specific pathways underlying this immune dysregulation. Further studies are needed to evaluate the role of targeted immunomodulatory therapies for CVID-associated intestinal disorders.

Navigating the management complexity in long-term asymptomatic immunodeficiency.

Background: Common variable immunodeficiency disorder (CVID) is a condition associated with recurrent infections and non-infectious outcomes, including lung disease like bronchiectasis and granulomatous and lymphocytic interstitial lung diseases (GLILD), autoimmune disease, enteropathy, and lymphoma. Treatment involves initiation of replacement immunoglobulin (Ig), which is a lifelong commitment. Prior to Ig replacement, life expectancy for patients with CVID was less than 15 years. With replacement Ig, it has improved to over 50 years. In most cases, patients present to a clinician with a history of recurrent infections, and treatment is indicated. However, in patients with asymptomatic disease, the best timing to start treatment can be difficult to determine. Case: We present a case of an otherwise healthy male who had an incidental diagnosis of CVID. Results: Workup revealed hypogammaglobulinemia for over 30 year. Discussion: Though successful in reducing infections, Ig replacement can come with many side effects, as well as a heavy medical burden to the patient and the healthcare system. It is also a big life adjustment, and can greatly affect a patient's quality of life. In the military, a diagnosis of an immunodeficiency, and the need for monthly intravenous immunoglobulin (IVIG) can be detrimental to deployment readiness, and a patient's military career. Risks and benefits need to be weighed prior to initiating Ig therapy.

Common variable immune deficiency: Dissection of the variable.

Starting about 60 years ago, a number of reports appeared that outlined the severe clinical course of a few adult subjects with profound hypogammaglobinemia. Puzzled by the lack of family history and adult onset of symptoms in most, the name "acquired" hypogammaglobinemia was given, but later altered to the current name common variable immune deficiency. Pathology reports remarked on the loss of lymph node architecture and paucity of plasma cells in lymphoid tissues in these subjects. While characterized by reduced serum IgG and IgA and often IgM, and thus classified among the B-cell defects, an increasing number of cellular defects in these patients have been recognized over time. In the early years, severe respiratory tract infections commonly led to a shortened life span, but the wide spread availability of immune globulin concentrates for the last 25 years has improved survival. However, chronic non-infectious inflammatory and autoimmune conditions have now emerged as challenging clinical problems; these require further immunologic understanding and additional therapeutic measures. Recent study of this phenotypic syndrome have provided an increasingly fertile ground for the identification of autosomal recessive and now more commonly, autosomal dominant gene defects which lead to the loss of B-cell development in this syndrome.

Piecing together the subtle clues of common variable immunodeficiency.

ABSTRACT: Common variable immunodeficiency (CVID) is a primary immunodeficiency disorder that results in decreased immunity and increased infection risk. This multisystem disorder often presents as recurrent, prolonged respiratory tract infections. Other manifestations include chronic lung disease, systemic granulomatous disease, malignancies, enteropathy, splenomegaly, and autoimmune disease including cytopenias. Diagnosis often is delayed, affecting patient quality of life, morbidity, and mortality. This article reviews the presentation, diagnosis, and management of patients with CVID.

Health-related quality of life in primary immunodeficiencies: Impact of delayed diagnosis and treatment burden.

Accurate and timely diagnosis of primary immunodeficiencies (PID) is an ongoing effort. Individuals with PID can be severely impacted by their disease and many experience chronic complications, treatment burden, and reduced quality of life (QoL). This review focuses on the impact of delayed diagnosis and treatment burden on patient QoL and outcomes. Adults tend to experience longer delays in diagnosis than pediatric populations. The median diagnostic delay has reduced over recent decades, but remains high for some antibody deficiency variants, such as common variable immunodeficiency. The largest burden impacting QoL tends to be poorly controlled disease and persistent chronic conditions rather than treatment burden. Hospitalization, physician/emergency room visits, and bronchiectasis were the most expensive PID complications prior to diagnosis and cost analyses estimate cost reductions once appropriate treatment is initiated. A combination of poor awareness, lack of infrastructure, and resources supporting national registries play a major role in delayed diagnosis.

An Expert Opinion/Approach: Clinical Presentations, Diagnostic Considerations, and Therapeutic Options for Gastrointestinal Manifestations of Common Variable Immune Deficiency.

Common variable immunodeficiency (CVID) is the most common symptomatic primary immunodeficiency. It is characterized by impaired B-cell differentiation. Although patients can be diagnosed with CVID anytime during their lifetime, most patients have symptoms for 5-9 years before their diagnosis. The diagnosis of CVID starts with a detailed history focusing on the infectious and noninfectious manifestations of the disease. In patients who are suspected to experience CVID, quantitative immunoglobulins (Ig) should be checked to confirm the diagnosis. IgG should be at least 2 times less than the age-specific SD along with either a low IgA or IgM and with evidence of impaired vaccine response. CVID is usually associated with infectious and/or noninfectious conditions, the latter of which can be inflammatory, autoimmune, lymphoproliferative, or malignant, among other manifestations. Ig therapy has positively affected the disease course of patients with infectious complications but has limited effect on the noninfectious manifestations because the noninfectious complications are related to immune dysregulation involving B cells and T cells rather than primarily due to antibody deficiency. When the gastrointestinal (GI) system is involved, patients with CVID may display signs and symptoms that mimic several GI conditions such as celiac disease, pernicious anemia, or inflammatory bowel diseases. The inflammatory bowel disease-like condition is usually treated with steroids, 5-aminosalicylates, thiopurines, or biologic agents to control the inflammation. In this review, the clinical presentations, diagnostic considerations, and therapeutic options for GI manifestations of CVID will be discussed to facilitate the individualized management of these often-complex patients.

Immunogenicity and Safety of the Spikevax® (Moderna) mRNA SARS-CoV-2 Vaccine in Patients with Primary Humoral Immunodeficiency.

INTRODUCTION: Reports on the immunogenicity and efficacy of the Spikevax® vaccine against SARS-CoV-2 in immunodeficient patients are still scarce. We aimed to evaluate the safety and immunogenicity of the vaccine in patients with primary humoral immunodeficiency. METHODS: We enrolled 46 patients, including 34 patients with common variable immunodeficiency (CVID), 10 patients with unclassified hypogammaglobulinemia (HypoIg), and 2 patients with X-linked agammaglobulinemia. We collected the blood samples before vaccination (D 0), and 10 days (D +38) and 90 days (D +118) after the second vaccination. Further, we quantified SARS-CoV-2-specific T-cell response (QuantiFERON ELISA test), serum anti-RBD IgG, and anti-RBD IgA-specific antibodies (enzyme immunoassay). RESULTS: We found that the vaccination elicited predominantly mild adverse events, comparable to healthy population. Vaccination response negatively correlated with a value of Immune Deficiency and Dysregulation Activity in all measured parameters. D +38, seroconversion for anti-RBD IgG and anti-RBD IgA was observed in 65% and 21% CVID patients, respectively. SARS-CoV-2-specific T-cell response was detected in less than 50% of CVID patients. Meanwhile, HypoIg patients had 100%, 90%, and 60% positivity rates for anti-RBD IgG, anti-RBD IgA, and T-cell response, respectively. Three months after the second vaccination, 82% of the responders remained positive for anti-RBD IgG, but only less than 50% remained positive for T-cell activity in CVIDs. Low immunogenicity was observed in patients with lung involvement and/or rituximab treatment history. No SARS-CoV-2 infection was reported within 6 months after the second vaccination. CONCLUSION: Spikevax® seems to be safe with satisfactory immunogenicity in patients with primary humoral immunodeficiency.

Recurrent asthma exacerbations: co-existing asthma and common variable immunodeficiency.

Common variable immunodeficiency is characterized by impaired B-cell differentiation and defective immunoglobulin production manifesting as recurrent respiratory tract infections. While the condition can masquerade as asthma, late diagnosis of CVID in known asthmatic is rarely reported.We present the case of a 43-year-old lady with recurrent episodes of wheeze, cough, sinusitis and multiple lower respiratory tract infections. Transiently responsive to antibiotics and steroids. These episodes had been occurring for many years and she had a longstanding clinical diagnosis of asthma.As part of her work up for recurrent respiratory tract infections a CT thorax was performed and demonstrated bronchiectasis. Further tests including Immunoglobulin levels revealed critically low IgG, IgM, and IgA levels. Immunoglobulin replacement therapy was commenced with a reduction in exacerbation frequency and severity, and objective improvement of asthma control. Subsequent lung function tests demonstrated reversible airflow limitation (obstructive lung function with 13% reversibility in FEV1 post-bronchodilator) consistent with asthma.Our case illustrates the importance of searching for alternate and co-existent diagnoses in patients diagnosed with asthma who are unresponsive to conventional therapy. We believe that serum immunoglobulin measurement should form a component of such a workup.

The pediatric common variable immunodeficiency - from genetics to therapy: a review.

Common variable immunodeficiency (CVID) is the most prevalent antibody deficiency, characterized by remarkable genetic, immunological, and clinical heterogeneity. The diagnosis of pediatric CVID is challenging due to the immaturity of the immune response and sustained actively developing antibody affinity to antigens and immunological memory that may overlap with the inborn error of immunity. Significant progress has been recently done in the field of immunogenetics, yet a paucity of experimental and clinical studies on different systemic manifestations and immunological features of CVID in children may contribute to a delayed diagnosis and therapy. In this review, we aimed at defining the variable epidemiological, etiological, and clinical aspects of pediatric CVID with special emphasis on predominating infectious and non-infectious phenotypes in affected children. CONCLUSION: While pediatric CVID is a multifaceted and notorious disease, increasing the pediatricians' awareness of this disease entity and preventing the diagnostic and therapeutic delay are needed, thereby improving the prognosis and survival of pediatric CVID patients. WHAT IS KNOWN: • CVID is an umbrella diagnosis characterized by complex pathophysiology with an antibody deficiency as a common denominator. • It is a multifaceted disease characterized by marked genetic, immunological, and clinical heterogeneity.. WHAT IS NEW: • The diagnosis of pediatric CVID is challenging due to the immaturity of innate and adaptive immune response. • Increasing the pediatricians' awareness of CVID for the early disease recognition, timely therapeutic intervention, and improving the prognosis is needed.

[Antibodydeficiencies Epidemiology, Clinical manifestation, Diagnostics and Therapy]. / Antikörpermangelsyndrome.

Antibodydeficiencies Epidemiology, Clinical manifestation, Diagnostics and Therapy Abstract. Primary Immune Deficiencies (PID) are caused by a genetically induced malformation/dysfunction of the immune system. Leading symptoms include susceptibility to infection, autoimmune diseases, lymphoproliferative, allergic as well as malignant diseases. They can be divided into ten main groups, including the primary antibody deficiency syndromes (PAD) in adults. The most well-known PADs include the variable immunodeficiency syndrome (CVID), Bruton's agammaglobulinaemia, IgG subclass deficiencies, immunoglobulin A deficiency, Antibody deficiency and transient childhood hypogammaglobulinaemia. Secondary hypogammaglobulinaemia by medicinal products, haematological diseases, malignancies and infections should be excluded. Delayed diagnosis of CVID is associated with a significant increase in morbidity and an increase in mortality. In addition to vaccinations, immunoglobulin replacement therapy is used therapeutically.

COMMON VARIABLE IMMUNODEFICIENCY: PREDISPOSING OR PROTECTIVE FACTOR FOR SEVERE COMPLICATIONS OF COVID-19?

Coronavirus disease 2019 (COVID-19) is an emerging infectious disease caused by severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2). The usual presentation of the disease is a common cold-like illness but it can present with more severe and sometimes fatal manifestations. Immunocompromised patients such as those with common variable immunodeficiency (CVID) also are among the infected population. A limited number of reports have been published concerning CVID patients with COVID-19. The main reported symptoms were fever, cough, dyspnea and fatigue while the median duration of illness was 19 (interquartile range 14-26.5) days. Total recovery rate was 88.4%. It is still unknown whether primary immunodeficiency interacts as a predisposing or protective factor against the severe forms of COVID-19. Substitute immunoglobulin (IG) therapy is the only treatment option for CVID. Some reports suggest that early administration of intravenous IGs or convalescent plasma infusion may positively influence the outcome of COVID-19 in these patients.

Adverse reactions in a large cohort of patients with inborn errors of immunity receiving intravenous immunoglobulin.

BACKGROUND: Intravenous immunoglobulins (IVIg) are the major treatment in inborn errors of immunity (IEI) disorders; However, IVIg infusions show some adverse effects. We aimed to assess the adverse reactions of IVIg infusions. METHODS: Data of IVIg infusions in IEI patients were collected from 2011 to 2021. Totally, 363 IEI patients received IVIg regularly in Iran entered the study. The adverse reactions are classified regarding their severity and chronicity. RESULTS: 22,667 IVIg infusions were performed in the study. 157 patients (43.2%) and 1349 (5.9%) infusions were associated with at least one type of adverse reaction. The highest rates of adverse reactions were seen in severe combined immunodeficiency. Myalgia, chills, headache, fever, and hypotension were the most frequent adverse effects of IVIg. CONCLUSION: The reactions affect almost half of the patients mainly in the first infusions which necessitate the close observation of IEI patients receiving IVIg.

Pulmonary Hypertension in Patients with Common Variable Immunodeficiency.

PURPOSE: Common variable immunodeficiency (CVID) is known to cause infectious, inflammatory, and autoimmune manifestations. Pulmonary hypertension (PH) is an unusual complication of CVID with largely unknown characteristics and mechanisms. METHODS: We report the clinical, functional, hemodynamics, radiologic and histologic characteristics, and outcomes of CVID-associated PH patients from the French PH Network. RESULTS: Ten patients were identified. The median (range) age at CVID diagnosis was 36.5 (4-49) years and the median delay between CVID and PH diagnosis was 12 (0-30) years. CVID-associated PH affected predominantly women (female-to-male ratio 9:1). Most patients were New York Heart Association functional class III with a severe hemodynamic profile and frequent portal hypertension (n = 6). Pulmonary function tests were almost normal in 70% of patients and showed a mild restrictive syndrome in 30% of patients while the diffusing capacity for carbon monoxide was decreased in all but one patient. High-resolution computed tomography found enlarged mediastinal nodes, mild interstitial infiltration with reticulations and nodules. Two patients had a CIVD-interstitial lung disease, and one presented with bronchiectasis. Pathologic assessment of lymph nodes performed in 5 patients revealed the presence of granulomas (n = 5) and follicular lymphoid hyperplasia (n = 3). At last follow-up (median 24.5 months), 9 patients were alive, and one patient died of Hodgkin disease. CONCLUSION: PH is a possible complication of CVID whose pathophysiological mechanisms, while still unclear, would be due to the inflammatory nature of CVID. CVID-associated PH presents as precapillary PH with multiple possible causes, acting in concert in some patients: a portal hypertension, a pulmonary vascular remodeling, sometimes a pulmonary parenchymal involvement and occasionally an extrinsic compression by mediastinal lymphadenopathies, which would be consistent with its classification in group 5 of the current PH classification.

Common Variable Immunodeficiency, Autoimmune Hemolytic Anemia, and Pancytopenia Associated With a Defect in IKAROS.

OBJECTIVE: Mutations in IKZF1, which encodes Ikaros family zinc finger 1 (IKAROS) transcription factor, are associated with recurrent infections, cytopenia, autoimmune diseases, and hematologic malignancies. Diverse clinical phenotypes resulting from IKZF1 mutations include pulmonary fungal infections, cytopenia, autoimmune hemolytic anemia (AIHA), and malignancies. In this study, we aimed to assess the DNA-binding ability and pericentromeric (PC) localization of a variant of IKZF discovered in a patient. MATERIALS AND METHODS: DNA-binding ability of a pathogenic IKZF variant was tested using electrophoretic mobility shift assay and PC localization of the variant was assessed by immunofluorescent microscopy in NIH3T3 cells. RESULTS: Clinical features of a 3-month-old male infant who underwent hematopoietic stem cell transplantation because of an IKZF1 mutation-associated common variable immunodeficiency, AIHA, and pancytopenia are described. DNA studies revealed a heterozygous missense variant (IKZF1 NM_006060 c.427C>T; p.R143W). Cotransfection studies revealed that mutant R143W has a partial dominant-negative effect over PC targeting and DNA binding. CONCLUSIONS: IKZF1 mutation must be kept in mind if neonatal AIHA, common variable immunodeficiency, and pancytopenia are observed.

Clinical features and immunoglobulin replacement therapy outcomes of adults with common variable immunodeficiency: a single centre experience

Background/aim: Common variable immunodeficiency (CVID) characterized by defective immunoglobulin production is the most prevalent form of symptomatic primary immunodeficiency (PID) in adults. We aimed to reveal the clinical features of adults with CVID and to evaluate the effects of immunoglobulin replacement treatment (IRT) on hemato-immunological findings. Materials and methods: This study included 26 adult patients receiving IRT. Two measurements of complete blood counts and major immunoglobulin levels obtained at the beginning-end of follow up period were used for comparisons. Lymphocyte subsets and B-cell subgroups were measured only at the time of presentation. Results: The most common complications were related to respiratory and digestive systems and organomegaly. Chronic diarrhoea and low body weight were positively correlated with the percentage of CD8+ T cells (p = 0.019 and p = 0.003, respectively) but negatively correlated with the CD4/CD8 ratio and the percentage of CD19+ B cells (p = 0.019 and p = 0.005 for both parameters, respectively). At the end of period, the distribution of haematological parameters significantly improved, and immunoglobulin M (IgM) level increased to detectable levels (p = 0.035). Conclusions: There are apparent relationships among chronic diarrhoea and low body weight, and deterioration of T and B cell immunity in adults with CVID. IRT improves the whole blood parameters and stimulates immunoglobulin M (IgM) production. The later effect supports the immunomodulatory feature of this therapy.

Common Variable Immunodeficiency: Epidemiology, Pathogenesis, Clinical Manifestations, Diagnosis, Classification, and Management.

Common variable immunodeficiency (CVID) is a heterogeneous disorder characterized by hypogammaglobulinemia and increased susceptibility to recurrent bacterial infections. It is the most frequent symptomatic antibody deficiency, with a wide variety of infectious and noninfectious complications. Numerous studies have demonstrated that immunological and genetic defects are involved in the pathogenesis of CVID. However, in most cases, the genetic background of the disease remains unidentified. This review aims to discuss various aspects of CVID, including epidemiology, pathogenesis, symptoms, diagnosis, classification, and management.