The atopic march recognizes the increased occurrence of asthma, allergic rhinitis, or both after atopic dermatitis (AD) onset. Mechanisms for developing atopic comorbidities after AD onset are poorly ...understood but can involve the impaired cutaneous barrier, which facilitates cutaneous sensitization. The association can also be driven or amplified in susceptible subjects by a systemic TH2-dominant immune response to cutaneous inflammation. However, these associations might merely involve shared genetic loci and environmental triggers, including microbiome dysregulation, with the temporal sequence reflecting tissue-specific peak time of occurrence of each disease, suggesting more of a clustering of disorders than a march. Prospective longitudinal cohort studies provide an opportunity to explore the relationships between postdermatitis development of atopic disorders and potential predictive phenotypic, genotypic, and environmental factors. Recent investigations implicate disease severity and persistence, age of onset, parental atopic history, filaggrin (FLG) mutations, polysensitization, and the nonrural environment among risk factors for development of multiple atopic comorbidities in young children with AD. Early intervention studies to repair the epidermal barrier or alter exposure to the microbiome or allergens might elucidate the relative roles of barrier defects, genetic locus alterations, and environmental exposures in the risk and sequence of occurrence of TH2 activation disorders.
Aminopeptidase N (CD13) is a widely expressed ectoenzyme with functions that do not always depend on its enzymatic activity: an aspect that has been overlooked. Numerous CD13-targeting tools have ...been developed in the last few years. Several of them are already undergoing clinical trials, and there are promising reports on the effectiveness of others in animal models of disease. However, their efficacy might be obscured by their effects on unrecognized functions of CD13, resulting in unexpected complications. The purpose of this review is (i) to discuss the various functions ascribed to CD13 and the possible mechanisms behind them and (ii) to consider some of the questions that need to be answered to achieve a better understanding of the biological relevance of these functions, a more precise interpretation of the results obtained after their manipulation and a more rational design of CD13-targeting agents.
To evaluate the impact of atopic dermatitis on families of pediatric patients.
This cross-sectional, web-based survey of children/adolescents (6 months to <18 years old) with atopic dermatitis and ...their parents and caregivers was conducted in 18 countries encompassing North America, Latin America, Europe, Middle East/Eurasia, and East Asia. Children and adolescents with atopic dermatitis and their parents and caregivers were identified by the International Study of Asthma and Allergies in Childhood criteria and ever being told by a physician that they had “eczema”. Atopic dermatitis severity was assessed using the Patient-Oriented Eczema Measure and the Patient Global Assessment. Atopic dermatitis impact on families’ lives was evaluated using the Dermatitis Family Impact questionnaire and stand-alone questions on hours of atopic dermatitis-related care (past week) and missed work days (past 4 weeks) owing to their child’s atopic dermatitis.
A total of 7465 pairs of pediatric participants with atopic dermatitis and their parents or caregivers were surveyed. Across age groups, the Dermatitis Family Impact questionnaire total score for all regions ranged from 7.1 to 8.6, 13.2 to 14.9, and 17.0 to 17.2 for Patient-Oriented Eczema Measure mild, moderate, and severe atopic dermatitis, respectively. Subscale scores showed that greater atopic dermatitis severity had a greater impact on all family life domains, including sleep and tiredness. No specific patterns or trends were observed across age groups. Time spent on childcare and missed work days increased with atopic dermatitis severity.
Across pediatric age groups and geographic regions, greater atopic dermatitis severity was associated with a greater negative impact on physical, emotional, social, and economic components of family life.
During inflammation, cell surface adhesion molecules guide the adhesion and migration of circulating leukocytes across the endothelial cells lining the blood vessels to access the site of injury. The ...transmembrane molecule CD13 is expressed on monocytes and endothelial cells and has been shown to mediate homotypic cell adhesion, which may imply a role for CD13 in inflammatory monocyte trafficking. Here, we show that ligation and clustering of CD13 by mAb or viral ligands potently induce myeloid cell/endothelial adhesion in a signal transduction-dependent manner involving monocytic cytoskeletal rearrangement and filopodia formation. Treatment with soluble recombinant (r)CD13 blocks this CD13-dependent adhesion, and CD13 molecules from monocytic and endothelial cells are present in the same immunocomplex, suggesting a direct participation of CD13 in the adhesive interaction. This concept is strengthened by the fact that activated monocytic cells adhere to immobilized recombinant CD13. Furthermore, treatment with anti-CD13 antibodies in a murine model of peritonitis results in a decrease in leukocyte infiltration into the peritoneum, suggesting a potential role for CD13 in leukocyte trafficking in vivo. Therefore, this work supports a new direction for CD13 biology, where these cell surface molecules act as true molecular interfaces that induce and participate in critical inflammatory cell interactions.
Atopic dermatitis in the pediatric population Silverberg, Jonathan I.; Barbarot, Sebastien; Gadkari, Abhijit ...
Annals of allergy, asthma, & immunology,
April 2021, Volume:
126, Issue:
4
Journal Article
Peer reviewed
Open access
Little is known on the current global prevalence of atopic dermatitis (AD) in the pediatric population.
To estimate the real-world global prevalence of AD in the pediatric population and by disease ...severity.
This international, cross-sectional, web-based survey of children and adolescents (6 months to <18 years old) was conducted in the following 18 countries: North America (Canada, United States), Latin America (Argentina, Brazil, Columbia, Mexico), Europe (France, Germany, Italy, Spain, United Kingdom), Middle East and Eurasia (Israel, Saudi Arabia, Turkey, United Arab Emirates, Russia), and East Asia (Japan, Taiwan). Prevalence was determined using the following 2 definitions: (1) diagnosed as having AD according to the International Study of Asthma and Allergies in Childhood (ISAAC) criteria and self- or parent-report of ever being told by a physician that they or their child child had AD (eczema); and (2) reported AD based on the ISAAC criteria only. Severity was assessed using the Patient Global Assessment (PtGA) and Patient-Oriented Eczema Measure (POEM).
Among 65,661 responders, the 12-month diagnosed AD prevalence (ISAAC plus self-reported diagnosis) ranged from 2.7% to 20.1% across countries; reported AD (ISAAC only) was 13.5% to 41.9%. Severe AD evaluated with both PtGA and POEM was generally less than 15%; more subjects rated AD as mild on PtGA than suggested by POEM. No trends in prevalence were observed based on age or sex; prevalence was generally lower in rural residential settings than urban or suburban.
This global survey in 18 countries revealed that AD affects a substantial proportion of the pediatric population. Although prevalence and severity varied across age groups and countries, less than 15% had severe AD.
IntroductionAtopic dermatitis (AD) is a chronic inflammatory skin disease often associated with atopic comorbidities and has significant impact on children and their families. There is a lack of ...robust and longitudinal long-term data on disease characteristics and typical clinical practice with currently available treatments in children with moderate-to-severe AD. Hence, an observational study is needed to evaluate AD characteristics and progression in paediatric patients with moderate-to-severe AD.Methods and analysisPediatric Study in Atopic Dermatitis (PEDISTAD) is a prospective, observational, longitudinal study in paediatric patients with moderate-to-severe AD who are currently receiving systemic or topical treatment and whose disease is not adequately controlled by topical prescription therapies or for whom those therapies are not medically advisable. 1300 children at 100–150 sites in approximately 20 countries worldwide will be enrolled and followed for 5 years. AD therapy is at the discretion of the investigator. Data collected will include: AD disease characteristics and comorbidities; current therapy for AD and initiation of new treatments/changes in current treatment; patient-reported/caregiver-reported outcomes; days missed from school/work for the patient/caregiver; healthcare professional visits; safety and biomarkers.Ethics and disseminationThis study is conducted in accordance with the principles established by the 18th World Medical Assembly and all subsequent amendments and the guidelines for Good Epidemiology Practice. Each individual country assures that ethics approval has been received and local regulatory requirements are met. Ethics approval has been obtained in all countries currently participating in PEDISTAD. Study data will be disseminated in manuscripts submitted to peer-reviewed medical journals as well as in abstracts submitted to congresses and in the resulting posters and presentations.Trial registration numberNCT03687359; pre-results.
CD13/aminopeptidase N is a transmembrane peptidase that is induced in the vasculature of solid tumors and is a potent angiogenic regulator. Here, we demonstrate that CD13 controls endothelial cell ...invasion in response to the serum peptide bradykinin by facilitating signal transduction at the level of the plasma membrane. Inhibition of CD13 abrogates bradykinin B2 receptor internalization, leading to the attenuation of downstream events such as bradykinin-induced activation of Cdc42 and filopodia formation, and thus affects endothelial cell motility. Investigation into mechanisms underlying this block led us to focus on B2R internalization via membrane-dependent mechanisms. Membrane disruption by depletion of cholesterol or trypsinization halts B2R internalization, invasion, and filopodia formation, which can be recovered with addition of cholesterol. However, this functional recovery is severely impaired in the presence of CD13 antagonists, and the distribution of membrane proteins is disordered in treated cells, suggesting a role for CD13 in plasma membrane protein organization. Finally, exogenous expression of wild-type but not mutant CD13 further alters protein distribution, suggesting peptidase activity is required for CD13's regulatory activity. Therefore, CD13 functions as a novel modulator of signal transduction and cell motility via its influence on specific plasma membrane organization, thus regulating angiogenesis.
PDF
