Type 2 immunity-driven diseases: Towards a multidisciplinary approach

Targeting of the IL-5 pathway in severe asthma reduces mast cell progenitors

BACKGROUND

Therapies targeting IL-5 or its receptor (IL-5Rα) are currently used to treat patients with severe eosinophilic asthma.

OBJECTIVE

We sought to investigate the impact of anti-IL-5 and anti-IL-5Rα biological therapies on mast cells (MCs) and their progenitors.

METHODS

Surface IL-5Rα expression was investigated on MCs and their progenitors in mouse lungs and bone marrow and in human lungs and blood. Isolated human MC progenitors cultured in the presence or absence of IL-5 were analyzed in vitro. Circulating MC progenitors were quantified in patients with severe asthma before and after anti-IL-5 (mepolizumab) or anti-IL-5Rα (benralizumab) therapy. Gene expression analysis of MC progenitors was performed before and after anti-IL-5Rα therapy.

RESULTS

Approximately 50% of the human primary lung MCs and 30% of the human MC progenitors from individuals with allergic asthma expressed IL-5Rα. In patients with mild to moderate allergic asthma and mice with acute allergic airway inflammation, the fraction of IL-5Rα+ MC progenitors was elevated. In addition, IL-5 promoted the proliferation and/or survival of isolated human MC progenitors. Furthermore, patients with severe asthma from 2 independent cohorts demonstrated a reduction in blood MC progenitors after anti-IL-5 or anti-IL-5Rα treatment. This was associated with improved asthma control as well as a decline in both blood eosinophils and TH2 cells. Finally, the blood MC progenitors remaining after anti-IL-5Rα (benralizumab) treatment exhibited a downregulated expression of genes involved in growth and proliferation.

CONCLUSIONS

This study introduces the possibility that the clinical effects of targeting IL-5/IL-5Rα in severe asthma may also involve reduction of MC populations.

Preclinical Development of SHR-1819, a Potent Humanized IL-4Rα Antibody for Treating Type 2 Inflammatory Diseases

Background

Interleukin (IL)-4 and IL-13 are critical pathogenic factors for type 2 inflammation-related allergic diseases, sharing the mutual receptor subunit IL-4Rα. However, it was ineffective for certain type 2 inflammation diseases by targeting IL-4, IL-13 ligand alone or both in clinical studies. The work presented herein aimed to evaluate the preclinical efficacy and pharmacokinetics profile of a novel monoclonal antibody against IL-4Rα, SHR-1819, as a promising therapy for type 2 inflammation diseases.

Methods

SHR-1819 was generated through immunization by C57BL/6 mice with recombinant hIL-4Rα protein, followed by humanization and affinity maturation. Then, its binding properties with IL-4Rα were determined using surface plasmon resonance (SPR) and ELISA. In vitro inhibitory effects of SHR-1819 were assessed on hIL-4-/hIL-13-induced cell proliferation and signal transducer and activator of transcription 6 (STAT6) signaling activation. In vivo efficacy of SHR-1819 was evaluated in several type 2 inflammatory diseases models, including asthma, atopic dermatitis (AD), and allergic rhinitis (AR) by using hIL-4/hIL-4Rα transgenic mice. Furthermore, the pharmacokinetic (PK) profiles of SHR-1819 were characterized.

Results

SHR-1819 showed high binding affinity to human IL-4Rα and effectively blocked IL-4Rα at sub-nanomolar concentration. In vitro assays indicated that SHR-1819 significantly inhibited TF-1 cell proliferation and STAT6 activation induced by hIL-4/hIL-13. In the asthma model, SHR-1819 could reduce airway hyperresponsiveness, decrease serum IgE levels, and alleviated inflammatory lung cell infiltration. In the AD model, SHR-1819 could significantly alleviate inflammatory and skin symptoms. In the AR model, it could remarkably decrease the frequencies of nasal rubbing and sneezing, and inflammatory cell infiltration in nasal tissues. These in vivo efficacy studies demonstrated the therapeutic potential of SHR-1819 in preclinical disease models. Moreover, subcutaneous administration of SHR-1819 exhibited favorable bioavailability in mice.

Conclusion

The results supported SHR-1819 as a promising preclinical candidate for the treatment of type 2 inflammatory diseases, including asthma, AD and AR.

Skin Lipid Barrier: Structure, Function and Metabolism

Lipids are important skin components that provide, together with proteins, barrier function of the skin. Keratinocyte terminal differentiation launches unique metabolic changes to lipid metabolism that result in the predominance of ceramides within lipids of the stratum corneum (SC)-the very top portion of the skin. Differentiating keratinocytes form unique ceramides that can be found only in the skin, and generate specialized extracellular structures known as lamellae. Lamellae establish tight hydrophobic layers between dying keratinocytes to protect the body from water loss and also from penetration of allergens and bacteria. Genetic and immunological factors may lead to the failure of keratinocyte terminal differentiation and significantly alter the proportion between SC components. The consequence of such changes is loss or deterioration of skin barrier function that can lead to pathological changes in the skin. This review summarizes our current understanding of the role of lipids in skin barrier function. It also draws attention to the utility of testing SC for lipid and protein biomarkers to predict future onset of allergic skin diseases.

Spanish Consensus on Remission in Asthma (REMAS)

The concept of "remission" in asthma has been around for a long time and it has been a controversial topic. Despite the attempts of some studies to characterize this entity, the discussion continues. In the case of asthma there is still no clear definition, either in terms of its meaning or the parameters that should be included or whether it should be divided into clinical or complete remission. To help defining these controversial concepts, SEPAR has advocated the multidisciplinary working group REMAS (REMission in ASthma). Following the Delphi methodology and with the involvement of more than 120 specialists in asthma management, this group has arrived at a consensus on the definitions of remission in asthma and establishing the criteria and characteristics that will be of use in future studies evaluating the efficacy or effectiveness of treatments.

Multidisciplinary management of type 2 inflammation diseases using a screening tool

Dysregulation of type 2 (T2) immune response leads to an aberrant inflammatory reaction that constitutes the pathophysiological basis of diseases involving various organs. For this reason, several disorders can coexist in a single patient; however, as different specialists often treat these pathologies, T2 dysregulation, particularly when mild, is not always the first diagnostic suspicion. A breakdown in interdisciplinary communication or the lack of adequate tools to detect these entities can delay diagnosis, and this, together with a lack of coordination, can lead to suboptimal care. In this context, a multidisciplinary group of specialists in pneumology, immunology, allergology, dermatology and otorhinolaryngology compiled a list of the cardinal symptoms reported by patients presenting with T2 inflammation-related diseases: asthma, chronic rhinosinusitis, allergic rhinitis, allergic conjunctivitis, IgE-mediated food allergy, atopic dermatitis, eosinophilic oesophagitis, and NSAID-exacerbated respiratory disease (NERD). Using this information, we propose a simple, patient-friendly questionnaire that can be administered at any level of care to initially screen patients for suspected coexisting T2 diseases and referral to the appropriate specialist.

Race science without racists: how bigoted paradigms persist in allergy research

In the wake of the murder of George Floyd and the massacre in Buffalo, the editorial boards of the prominent scientific publication companies formally apologized for their journals' historical role in advancing race science and promised to improve their standards. However, flowery commentaries cannot undo the consistent pattern of endorsing biologic differences between ethnic groups, even when discussing diseases or traits that are not considered politically charged. In this report, an exemplar is made of a recent publication claiming to identify phenotypes of atopic dermatitis that are distinct between European Americans, Asians, and African Americans. The insufficiency of the evidence and logic underlying these claims are discussed. Although devoid of malice, numerous publications continue to demonstrate how claims of biological differences between races is mainstreamed in modern scientific publications. Overall, the goal of this work is to challenge the scientific community, particularly the publication companies, to evaluate how assumptions of innate biologic disadvantage have clouded assessments of racial disparities in disease beyond the topics that are more stereotypical of race science.

Role of Mast Cells in Eosinophilic Gastrointestinal Diseases

Mast cells play a central role in the pathogenesis of eosinophilic gastrointestinal disorders (EGIDs), including eosinophilic esophagitis. Their interactions with immune and structural cells, involvement in tissue remodeling, and contribution to symptoms make them attractive targets for therapeutic intervention. More is being discovered regarding the intricate interplay of mast cells and eosinophils. Recent studies demonstrating that depletion of eosinophils is insufficient to improve symptoms of EGIDs have raised the question of whether other cells may play a role in symptomatology and pathogenesis of EGIDs.

Combination of Biological Therapy in Severe Asthma: Where We Are?

Biological drugs have revolutionized the management of severe asthma. However, a variable number of patients remain uncontrolled or only partially controlled even after the appropriate administration of a biologic agent. The combination of two biologics may target different inflammatory pathways, and it has been used in patients suffering from uncontrolled severe asthma with evidence of both allergic and eosinophilic phenotypes or severe asthma and type2 comorbidities. Combination therapy has also been used to handle anti-IL4/13R induced hypereosinophilia. There is insufficient data on combining biologics for the treatment of severe uncontrolled asthma and type 2 comorbidities, also because of the high cost, and currently no guideline recommends dual biologic therapy. A systematic search was performed using the Medline and Scopus databases. Published data on concurrent administration of two biological drugs in severe, uncontrolled asthma patients has been reported in 28 real-world studies and 1 clinical trial. Data extraction was followed by a descriptive and narrative synthesis of the findings. Future studies should be conducted to further assess the safety, efficacy, and cost-effectiveness of this therapeutic strategy.

Addressing the unmet needs in patients with type 2 inflammatory diseases: when quality of life can make a difference

Background

Patients with asthma (AS), atopic dermatitis (AD), allergic rhinitis (AR), eosinophilic esophagitis (EoE), chronic rhinosinusitis with nasal polyps (CRSwNP), chronic urticaria (CU), non-steroidal anti-inflammatory drugs-exacerbated respiratory disease (N-ERD), and certain phenotypes of chronic obstructive pulmonary disease (COPD), among others, have a common underlying pathogenesis known as Type 2 inflammation (T2i). These diseases often coexist with other T2i conditions and have a substantial impact on the quality of life (QoL) of patients. However, limited data on patients' experiences, perspectives, and current management of T2i diseases have been published thus far.

Aims

This survey, promoted by the patient-driven T2i Network Project, aimed at identifying the common drivers and challenges related to the QoL of patients with T2i diseases by putting the patient's perspective at the force and including it in the design of new care strategies.

Methodology

An anonymous online survey was carried out through convenience sampling between May and June 2023. The survey was codesigned by members of different patient associations, healthcare professionals and healthcare quality experts, and implemented using EUSurvey and distributed through eight patient associations from Spain. The survey consisted of 29 questions related to the participant's sociodemographic features, a series of self-reported multiple choice or rating scale questions, including diagnosis, QoL measures, disease severity, healthcare resource utilization, and quality of care.

Results

The survey included 404 participants, members from eight patient associations, the majority of whom had moderate-to-severe self-reported disease severity (93%) and one or more coexisting pathologies related to T2i (59%). Patients with more than one pathology had a significantly greater impact on QoL than those with only one pathology (p < .001). Participants with self-reported severe symptoms reported significantly worse QoL than those with mild-to-moderate severity (p < .001). More than half of the patients (56%) felt constantly bothered by the unpredictability of their illness caused by potential exposure to known or unknown disease triggers. The lack of coordination between specialists and primary care was also expressed as an area of dissatisfaction by participants, with 52% indicating a complete lack of coordination and 21% indicating an average coordination.

Conclusion

This article reports the initial findings of a patient-led initiative, which highlights the common QoL challenges faced by individuals with type 2 inflammation-related diseases and emphasizes the importance of further clinical research to improve the management of this patient group. Considering the significant impact on QoL, a multidisciplinary approach integrated into new healthcare protocols has the potential to improve patient management and QoL, shorten the time to diagnosis and reduce healthcare resource utilization.

A Multidisciplinary Approach for Type 2 Allergic Diseases: What Do Biologics Teach Us?

Patients with atopic/allergic disorders, including atopic dermatitis (AD), allergic rhino-conjunctivitis (AR), chronic rhinosinusitis with/without nasal polyps (CRSwNP/CRSsNP), bronchial asthma, food allergy, and eosinophilic esophagitis (EoE), often share a common genetic background, a type Th2 polarized immune response, and several environmental factors [...].

From trained immunity in allergy to trained immunity-based allergen vaccines

Innate immune cells experience long lasting metabolic and epigenetic changes after an encounter with specific stimuli. This facilitates enhanced immune responses upon secondary exposition to both the same and unrelated pathogens, a process termed trained immunity. Trained immunity-based vaccines (TIbV) are vaccines able to induce innate immune memory, thus conferring heterologous protection against a broad range of pathogens. While trained immunity has been well documented in the context of infections and multiple immune-mediated diseases, the role of innate immune memory and its contribution to the initiation and maintenance of chronic allergic diseases remains poorly understood. Over the last years, different studies attempting to uncover the role of trained immunity in allergy have emerged. Exposition to environmental factors impacting allergy development such as allergens or viruses induces the reprogramming of innate immune cells to acquire a more pro-inflammatory phenotype in the context of asthma or food allergy. Several studies have convincingly demonstrated that prevention of viral infections using TIbV contributes to reduce wheezing attacks in children, which represent a high-risk factor for asthma development later in life. Innate immune cells trained with specific stimuli might also acquire anti-inflammatory features and promote tolerance, which may have important implications for chronic inflammatory diseases such as allergies. Recent findings showed that allergoid-mannan conjugates, which are next generation vaccines for allergen-specific immunotherapy (AIT), are able to reprogram monocytes into tolerogenic dendritic cells by mechanisms depending on metabolic and epigenetic rewiring. A better understanding of the underlying mechanisms of trained immunity in allergy will pave the way for the design of novel trained immunity-based allergen vaccines as potential alternative strategies for the prevention and treatment of allergic diseases.

White Paper on European Patient Needs and Suggestions on Chronic Type 2 Inflammation of Airways and Skin by EUFOREA

Background

Type 2 inflammation underlies the chronicity of disease in subgroups of patients with asthma, chronic rhinosinusitis with nasal polyps (CRSwNP) and atopic dermatitis (AD), that often co-exist. Although several studies have investigated the unmet needs of asthma, AD and CRSwNP as such, little is known about the similarities and differences in experiences and perspectives of the current management of patients with comorbid Type 2 inflammatory diseases.

Aims

To improve insight into the common and organ-specific needs of patients with Type 2 inflammation and comorbidities, allowing the formulation of recommendations to better address these needs in the future.

Methodology

This qualitative study was conducted between July 2021 and December 2021 using semi-structured face-to-face or telephone interviews with patients suffering from year-long severe chronic Type 2 inflammation and at least one co-morbid inflammatory condition. Seven participating academic centers in Europe interviewed asthma (Copenhagen and Leuven), CRSwNP (London, Amsterdam and Crete) and/or AD (Oldenburg and Zurich) patients on patient characteristics, disease severity, shortcomings of current care pathways and suggestions for improvement of care. Transcripts were analyzed using an inductive thematic analysis approach.

Results

Eighty-one patients with severe Type 2 inflammation and comorbidities were interviewed. Similar needs were recognized by patients with Type 2 inflammation, with both a lack of coordination in care and a lack of a real cure reported as being most frustrating. However, several needs are specific to asthma, CRSwNP and AD. Suggestions for improvement of care were generic across diseases, such as the implementation of a multidisciplinary approach, the improved facilitation of access to better treatments, the increase of general awareness on disease burden, and better educational programs for healthcare providers and patients. Of note, patients with CRSwNP also stated the need for alternatives to sinus surgery, whereas patients with asthma requested better medical care to prevent exacerbations and patients with AD would warmly welcome the reimbursement of emollients.

Conclusion

Patients with asthma, CRSwNP and AD have shared unmet needs that need to be addressed by physicians, the academic community and health policy makers. This survey provides unique recommendations made by patients for the implementation of better care.

In the Thick of It: Formation of the Tuberculous Granuloma and Its Effects on Host and Therapeutic Responses

The defining pathology of tuberculosis is the granuloma, an organized structure derived from host immune cells that surrounds infecting Mycobacterium tuberculosis. As the location of much of the bacteria in the infected host, the granuloma is a central point of interaction between the host and the infecting bacterium. This review describes the signals and cellular reprogramming that drive granuloma formation. Further, as a central point of host-bacterial interactions, the granuloma shapes disease outcome by altering host immune responses and bacterial susceptibility to antibiotic treatment, as discussed herein. This new understanding of granuloma biology and the signaling behind it highlights the potential for host-directed therapies targeting the granuloma to enhance antibiotic access and tuberculosis-specific immune responses.