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Nervous system involvement in systemic lupus erythematosus (SLE) is typically diagnosed on the basis of clinical psychiatric and/or neurologic syndromes (NPSLE). Neuropsychological tests can be used to assess nervous system integrity even in the absence of major NP syndromes. Their application has uncovered significant cognitive dysfunction, ranging from mild to severe, in a sizeable proportion of SLE patients irrespective of clinical NP status. Cognitive dysfunction has now been accepted as a bona fide manifestation of NPSLE. The heterogeneity of clinical NPSLE manifestations is paralleled by the diversity of cognitive deficits reported in different studies and within different patients. The success of attempts to explain these deficits on the basis of potential pathogenetic mechanisms, such as antibrain antibodies and proinflammatory cytokines, has been uneven. To date, the most robust findings have emerged in relation to antiphospholipid antibodies, which carry with them important therapeutic implications. [ABSTRACT FROM AUTHOR]

Summary Rhinitis and asthma are linked closely epidemiologically, as has been known for quite some time and emphasized in recent surveys (ISAAC study). Patients with seasonal allergic rhinitis without asthma symptoms can, as a group, be shown to have increased bronchial hyperresponsiveness. During the course of seasonal allergen exposure, patients with allergic rhinitis can be shown to have increased numbers of inflammatory cells (eosinophils and mast cells) in the lower airways, even without symptoms of lower airway disease. Long-standing observations from our laboratory have indicated fluctuations of eosinophil/basophil (Eo-B) progenitors in the peripheral blood in patients with seasonal allergic rhinitis, paralleling changes that are recognized in mature eosinophils and basophils in circulation. The finding of Eo-B progenitor decreases during the height of seasonal allergen exposure led us to hypothesize the concept of ‘in situ haemopoiesis’ to explain a process of systemic activation of haemopoietic mechanisms, in which communication among bone marrow peripheral blood and airway tissue compartments contributed to the allergic inflammatory process at a systemic level. Indeed, allergen challenge to the lower airways in atopic asthmatics elicits an immediate rise in Eo-B progenitors, especially in subjects with late phase responses. These original observations have been buttressed by a series of investigations demonstrating conclusively that exacerbations of asthma are attended by increases in peripheral blood Eo-B progenitors; that allergen challenge to dogs or mice with allergic airways inflammation elicits bone marrow progenitor responses, with trafficking of bone marrow cells to the airway either in pure upper or lower airway disease; and that allergen challenge to atopic asthmatics up-regulates the high affinity receptor for IL-5 on bone marrow progenitors (IL-5Rα), beginning a process of eosinophil differentiation that is probably driven by the release of a serum haemopoietic factor – as we have found in the canine model – which acts on the bone marrow and initiates a series of systemic events. [ABSTRACT FROM AUTHOR]

Focuses on the role of the bone marrow in providing an ongoing source of differentiating inflammatory cells to the upper and lower airways. Relationship between rhinitis and asthma; Sensitivity of a systemic hemopoietic process to inhaled corticosteroids; Production of growth factors.

This article focuses on basophil mast cell and eosinophil growth and differentiation factors in human allergic disease. The synergistic action of cytokines and the involvement of tissue micro-environments, including factors from fibroblasts, endothelial cells and epithelial cells, appear to be important determinants of both the numbers of effector cells, as well as their phenotype and heterogeneity in various tissues such as the nasal mucosa, lung, gastrointestinal tract and skin. It is tempting to speculate that the genetic underpinnings of the allergic diathesis involve basic defects in epithelial, endothelial or other micro-environmental controls, for classical and lineage-specific haemopoietic, and/or pro-inflammatory cytokine production.

We have described functional and biochemical characteristics of a distinct T-cell dependent guinea- pig basophil-stimulating factor (BSF), measured using a sensitive 7-day bone marrow culture assay, standardized with high-activity BSF present in serum-free splenic cell-conditioned medium (CM). In the present studies, the in vivo relevance of BSF was explored during protocols of induction of peripheral blood or tissue basophil responses to ovalbumin (OA) injection or Amblyomma wnerkanwn tick feeding. Pooled immune serum, taken from OA-injected inbred or outbred animals during induction of blood and marrow basophilia, contained an in vitro inhibitor to BSF at high concentrations and BSF-like activity at low concentrations; maximal stimulation of histamine synthesis by bone marrow cells in vitro was found in the presence of Day 4 OA-immune serum. In vivo studies in the OA model demonstrated maximal serum BSF-like activity at 48-72 hr before peak bone marrow basophil response, followed by a levelling off to 50% of maximum at 2 weeks. In the tick model, serum BSF-like activity was present in Day 8, but not Day I, post-primary infection and was maximal at Day 3 post-secondary infection; post-primary Day I serum was inhibitory to basophil growth in vitro. These observations suggest that BSF regulates the appearance of basophils in response to antigen in vivo by an effect on basophil progenitors. The observations stress the potential application of guinea-pig models to understanding the regulation of basophil production in allergic disorders. [ABSTRACT FROM AUTHOR]

Intestinal mastocytosis begins to develop in rats, depending on the strain, at 14 (outbred Sprague-Dawley, SD) or 16 (inbred Lewis, L) days after infection with the nematode Nippostrongylus brasiliensis (Nippo). We have investigated in vitro mastopoiesis from mesenteric lymph node (MLN) cells cultured at various intervals post-infection, using a modified Marbrook liquid system. Greater increases in mast cells (MC) were observed in cultures of SD-MLN removed on day 14 after Nippo infection (IMLN-14) than from MLN removed from uninfected animals (NMLN): seven- to twenty-fold versus up to two-fold at 2 weeks and forty- to two hundred-fold versus up to twenty- fold at 4 weeks, respectively (P«0.002). In contrast, similar differential increases in MC and histamine compared to uninfected controls, were demonstrated in 2 week cultures of MLN from L strain rats removed 17 (IMLN-17) and 20 (IMLN-20) but not 14 days after Nippo infection (P«0.001). The presence of phytohaemagglutinin (PHA) in vitro was associated with enhanced MC differentiation from both IMLN-17 and IMLN-20, while worm antigen (Ag) stimulated mastopoiesis from IMLN-17, but suppressed the response from IMLN-20 (P « 0.02). Conditioned media (CM) prepared from unstimulated or PHA-stimulated IMLN-32 (i.e. removed 32 days after Nippo infection) caused significant mastopoiesis from NMLN ha vitro when compared to no CM or Ag-stimulated CM (P«0.01). Either MC precursors or cells which help MC differentiation exist in increased numbers in MLN of Nippo-infected rats. Mitogenic or antigenic stimulation modulates in vitro mastopoiesis, either directly or through soluble factors derivable from MLN cells. These in vitro methods can be utilized to understand further mechanisms of intestinal mastocytosis in the rat. [ABSTRACT FROM AUTHOR]

The effect has been investigated of local administration of beclomethasone dipropionate (BDP) on cell numbers of nasal epithelial metachromatic cell (NMC) sub-populations. Twenty-one patients with perennial allergic rhinitis were studied in four groups according to the duration of treatment or after treatment with BDP. Nasal scrapings were taken after 1 week (Group 1) or 2 weeks (Group 2) of BDP treatment, or after discontinuing BDP for 1 week (Group 3) or 2 weeks (Group 4). Cells were fixed with Mota's lead acetate or 10% buffered formalin followed by toluidine blue staining to count the number of NMC and to classify these according to morphological sub-types (basophils or mast cells). Formalin-sensitive mast cells and basophils in nasal scrapings were reduced more than formalin-resistant mast cells with BDP treatment. Formalin-sensitive mast cells were also more prompt to recover from BDP than formalin-resistant mast cells. The results suggest that the formalin-sensitive NMC is a sub-population of cells which responds to BDP treatment in allergic rhinitis. [ABSTRACT FROM AUTHOR]

Examines the hemopoietic mechanisms in allergic rhinitis. Plasticity of stem cells; Activation of selective hemopoietic processes; Role of progenitor cells in allergic rhinitis.

Summary Background Dendritic cells (DC) are thought to play a key role in the initiation and maintenance of T cell immunity to inhaled antigens. While the density of DC within the bronchial mucosa is increased in stable asthma, there is little information currently available concerning the effects of allergen inhalation on DC in subjects with asthma. Objectives To enumerate changes in the numbers of circulating CD33+ myeloid DC in asthmatics, before and after allergen challenge. Methods Blood DC numbers were enumerated by flow cytometry before and at 3, 6 and 24 h after inhaled allergen and diluent in 10 mild, allergic asthmatic subjects. Results Blood DC numbers rapidly fell from 3.42 ± 0.30 × 107 /L at baseline, to 2.10 ± 0.17 × 107 /L by 3 h post-challenge (P < 0.01), and remained significantly below baseline values at both 6 and 24 h following allergen challenge. No such changes in DC numbers were noted after diluent challenge. A similar, early fall in circulating lymphocytes was also noted post-allergen challenge, whereas changes in circulating eosinophil and neutrophil numbers occurred more slowly. Conclusions A significant proportion of myeloid DC rapidly ‘disappear’ from the circulation following allergen inhalation, suggesting that margination of circulating myeloid DC, and their recruitment into the airway mucosa, is an important feature of the immune response to inhaled allergen. [ABSTRACT FROM AUTHOR]

Hematopoiesis refers to the development of blood cells in the body through the differentiation of pluripotent stem cells. Although hematopoiesis is a multifocal process during embryonic development, under homeostatic conditions it occurs exclusively within the bone marrow. There, a limited number of hematopoietic stem cells differentiate into a rapidly proliferating population of lineage-restricted progenitors that serve to replenish circulating blood cells. However, emerging reports now suggest that under inflammatory conditions, alterations in hematopoiesis that occur outside of the bone marrow appear to constitute a conserved mechanism of innate immunity. Moreover, recent reports have identified previously unappreciated pathways that regulate the egress of hematopoietic progenitor cells from the bone marrow, alter their activation status, and skew their developmental potential. These studies suggest that progenitor cells contribute to inflammatory response by undergoing in situ hematopoiesis (ISH). In this review, we highlight the differences between homeostatic hematopoiesis, which occurs in the bone marrow, and ISH, which occurs at mucosal surfaces. Further, we highlight factors produced at local sites of inflammation that regulate hematopoietic progenitor cell responses and the development of TH2 cytokine-mediated inflammation. Finally, we discuss the therapeutic potential of targeting ISH in preventing the development of inflammation at mucosal sites. [ABSTRACT FROM AUTHOR]

Haemopoietic myeloid progenitors contribute to the ongoing recruitment of pro-inflammatory cells, such as eosinophils and basophils (Eo/B), to target tissue sites in allergic diseases. It is apparent that the development of allergic inflammation is critically dependent on the ability of the bone marrow to support the proliferation, differentiation and mobilization of haemopoietic progenitors. The haemopoietic inductive microenvironment in the bone marrow is crucial for providing signals necessary for maintenance of progenitor populations at varying stages of lineage commitment and permitting these cells to circulate in the bloodstream. Progenitors demonstrate responsiveness to specific cytokines, which varies with stage of differentiation. Pro-inflammatory signals, Th2 cytokines in particular, generated following allergen challenge, can impact on haemopoietic progenitor differentiation and mobilization, leading to accelerated Eo/B production. Allergen inhalation by allergic asthmatics induces a time-dependent change in cytokine levels within the bone marrow compartment, influencing differentiation of Eo/B progenitors, as evidenced by the relationship between increased bone marrow IL-5 levels and Eo/B production. It is proposed that inhaled allergen induces trafficking of IL-5-producing T lymphocytes to the bone marrow, further promoting eosinophilopoiesis through IL-5R signalling. In this manner, Th2 lymphocyte trafficking from the airway may regulate events occurring in the bone marrow. Negative regulators of Eo/B differentiation, including Th1 cytokines, may prove to be important for restoring homeostasis. Eo/B progenitors are also altered in cord blood of infants at risk of atopy and asthma, offering a potential biomarker for, and raising the possibility that Eo/B progenitors are directly involved in the development of allergic disease. For example, changes in the expression of haemopoietic cytokine receptors on cord blood progenitor cells are associated with maternal allergic sensitization, atopic risk and its development, suggesting that haemopoietic processes underlying the allergic phenotype may begin to evolve in the perinatal period. [ABSTRACT FROM AUTHOR]

We have examined the biochemical and functional characteristics of mast cells grown in tissue culture from the mesenteric lymph node (MLN) of rats infected with the nematode Nippostrongylus brasiliensis and compared them with mast cells isolated from the small intestinal mucosa and peritoneal cavity of infected animals. Cultured mast cells (MC) and isolated intestinal mucosal mast cells (MMC) had a similar histamine content, and both contained type II protease (RMCP II) which was absent from peritoneal mast cells (PMC). PMC, MMC and cultured MC each responded to immunologically induced histamine secretion, but MMC and cultured MC were hyporesponsive to calcium ionophores and unresponsive to widely used PMC secretagogues including compound 48/80 and bee venom peptide 401. MMC and cultured MC also differed from PMC in their lack of responsiveness to the anti-allergic agent disodium cromoglycate. Thus, MC cultured from the MLN are distinct from PMC but have a biochemical and functional phenotype similar to that of intestinal MMC. [ABSTRACT FROM AUTHOR]

Nasal polyposis is a chronic inflammatory condition of the upper airways characterized by infiltration of activated inflammatory cells, including mast cells, both in the epithelium and in the stroma. The aim of this work was to study human must cells derived from two different anatomical sites within the same nasal polyp tissue. To this end, we isolated two distinct mast cell populations, one from the epithelial and the other from the stromal layers of individual human nasal polyp tissues. We examined the mediator content of the two mast cell populations, and found that stromal mast cells had a significantly higher content of tryptase compared with the epithelial mast cells from the same tissue. In addition, mast cells from the stromal compartment, but not those from the epithelium, released a significant amount of histamine after anti-IgE stimulation. By contrast, both populations released over 50% of the total histamine after non-specific stimuli (A23187 10-6 M). The content of mediators and the response to immunological activation were not significantly altered in patients receiving topical steroid therapy. It remains to be determined if the observed differences are the result of an intrinsic characteristic of the mast cell populations localized to separate tissue compartments, or reflect a different in vivo exposure lo stimuli such as antigens, or different surrounding structural or infiltrating cells. In conclusion, these data provide evidence of functional heterogeneity and differences in mediator content between mast cell subpopulations from a single human tissue. The failure of release of epithelial mast cell mediators from an immunologic stimulus may have implications concerning acute effects of antigen exposure in nasal polyposis. [ABSTRACT FROM AUTHOR]

Sputum cell-counts were studied in 7 non-smokers with corticosteroid-responsive chronic cough productive of sputum and 8 smokers with a clinical diagnosis of chronic bronchitis, all of whom had normal lung function tests and methacholine airway responsiveness, and in 10 non-smokers with asthma, examined during an exacerbation. Sputum from asthmatic patients and subjects with corticosteroid-responsive cough contained eosinophils and metachromatic cells. Macrophages were by far the dominant cell type in sputum from subjects with chronic bronchitis. Airway inflammation with eosinophils and metachromatic cells is not always accompanied by increased airway responsiveness, and current definitions of obstructive airways disease may need to be revised. [ABSTRACT FROM AUTHOR]

Background Haemopoietic progenitor cells ( HPC) migrate to sites of allergic inflammation where, upon stimulation with epithelial cytokines, they produce Th2 cytokines and differentiate into mature eosinophils and basophils. They also express Toll-like receptors ( TLR) involved in antimicrobial responses. Objective The objective of this study was to compare TLR expression on peripheral blood HPC and TLR-induced responses, in particular changes in epithelial cytokine receptors, in healthy and asthmatic subjects at baseline and following allergen challenge. Methods Ten healthy and 11 allergic asthmatic subjects were studied. HPC-enriched cell populations were stimulated with TLR-2, TLR-4 or TLR-9 ligands. TLR expression by circulating HPC and interleukin ( IL)-25 ( IL-17 RB), IL-33 ( ST2) and thymic stromal lymphopoietin receptor ( TSLPR) expression after TLR ligation were examined by flow cytometry at baseline and, in asthmatics, following allergen challenge. The effects of dexamethasone (Dex) on TLR-induced responses were also assessed. Results Asthmatics had significantly lower circulating HPC expressing TLR-2 and TLR-9 with a similar trend for TLR-4. TLR-4 stimulation of HPC yielded higher numbers of TSLPR+ cells in asthmatics compared with healthy subjects. A similar trend was seen for TLR-9 ligation, an effect further augmented by allergen inhalation. Allergen challenge also enhanced TLR-induced ST2 expression on HPC. Treatment with Dex in vitro increased TLR-4-induced TSLPR expression but had no effect on other epithelial cytokine receptors. Conclusions and Clinical Relevance These data demonstrate an interaction between allergen and TLR ligand exposure in asthmatics. Allergen inhalation augments the TLR-induced inflammatory response by HPC, possibly leading to increased 'in situ haemopoiesis' through up-regulation of TSLPR. These findings show that HPC may be a part of the pro-inflammatory cascade in pathogen-induced asthma exacerbation through their increased responsiveness to TLR stimulation. [ABSTRACT FROM AUTHOR]

Background An unresolved issue in T regulatory cells' cell biology is the lack of consensus on phenotypic markers that accurately define the natural Treg ( nTreg) population. Objectives To examine nTreg frequency and functional capacity in healthy controls and their frequency in asthmatic subjects using three different phenotypic strategies. We hypothesized that phenotypically different nTreg are quantitatively and functionally different. Methods Thirty-four healthy, non-asthmatic and 17 asthmatic subjects were studied. Three nTreg phenotypes were defined as follows: nTreg1 ( CD4+ CD25+Foxp3+), nTreg2 ( CD4+ CD25+ CD127lowFoxp3+), and nTreg3 ( CD4+ CD25highFoxp3+). The flow cytometric determination of nTreg frequency in peripheral blood ( PB) and bronchoalveolar lavage ( BAL) was performed using fluorescently labelled antibodies. Peripheral blood nTreg functional capacity was assessed using a CFSE-based suppression assay. Results There was a significantly lower frequency of PB nTreg3 compared to nTreg2 and nTreg1 ( P < 0.05). Both nTreg2 and nTreg3 had a significantly greater suppressive capacity than nTreg1 at T responder (Tresp) to nTreg ratios of 16 : 1 up to 1 : 1 ( P < 0.01). Asthmatics exhibited a significantly lower PB nTreg3 and nTreg1 frequency than healthy controls ( P < 0.05). There were no differences between healthy controls and asthmatic subjects when comparing BAL nTreg frequency. Conclusions and Clinical Relevance Phenotypically different nTreg subsets are quantitatively and functionally different and are variably observed in asthma. The CD4+ CD25highFoxp3+ phenotype was the least frequent, but demonstrated the greatest suppression, and was significantly lower in PB of asthmatic subjects. Consequently, it is imperative that nTreg phenotypes be clearly defined and that the interpretation of their frequency and function be phenotype specific. [ABSTRACT FROM AUTHOR]

Recent candidate gene and genome-wide association studies have identified 'protective' associations between the single-nucleotide polymorphism (SNP) rs1837253 in the TSLP gene and risk for allergy, asthma, and airway hyperresponsiveness. The absence of linkage disequilibrium of rs1837253 with other SNPs in the region suggests it is likely a causal polymorphism for these associations, having functional consequences. We hypothesized that rs1837253 genotype would influence TSLP secretion from mucosal surfaces. We therefore evaluated the secretion of TSLP protein from primary nasal epithelial cells (NECs) of atopic and nonatopic individuals and its association with rs1837253 genotype. We found that although atopic sensitization does not affect the secretion of TSLP from NECs, there was decreased TSLP secretion in NECs obtained from heterozygous (CT; 1.8-fold) and homozygous minor allele (TT; 2.5-fold) individuals, as compared with NECs from homozygous major allele individuals (CC; P<0.05), after double-stranded RNA (dsRNA) stimulation (50 μg ml−1). Our novel results show that rs1837253 polymorphism may be directly involved in the regulation of TSLP secretion. This may help explain the protective association of this genetic variant with asthma and related traits. Identifying functional consequences of SNPs in genes with previously reported clinical associations is critical in understanding and targeting allergic inflammation. [ABSTRACT FROM AUTHOR]

Background It is hypothesised that complex interactions between genetic and environmental factors give rise to allergy and asthma in childhood. The Canadian Healthy Infant Longitudinal Development ( CHILD) study was designed to explore these factors. Methods CHILD is a longitudinal, general population birth cohort study following infants from mid-pregnancy to age 5 years. Over this time period, biological samples, questionnaires, clinical measures and environmental data are collected. Results A total of 3624 families have been recruited, and many thousands of samples and questionnaires have been collected, annotated, and archived. This report outlines the rationale and methodology for collecting and storing diverse biological samples from parents and children in this study, and the mechanisms for their release for analyses. Conclusions The CHILD sample and data repository is a tremendous current and future resource and will provide a wealth of information not only informing studies of asthma and allergy, but also potentially in many other aspects of health relevant for Canadian infants and children. [ABSTRACT FROM AUTHOR]

The article discusses the challenges in and actions to be taken to cure allergy caused by diseases such as asthma, eczema and anaphylaxis. It discusses the needs of public, which are not met like inadequate control of complex allergic diseases, lack of treatments and strategies to prevent it. It further discusses how environment plays vital role in the induction of allergic diseases as they have environmental factors like quality of air, nutrition, climate, and ultra violet radiations.

Background Inhaled peptide challenge has been shown to induce T cell-mediated, isolated late asthmatic reaction ( LAR), characterized by recruitment of CD4+ T cells and increased levels of thymus and activation-regulated chemokine ( TARC; CCL17). Epithelial-derived thymic stromal lymphopoietin ( TSLP) has been shown to modulate dendritic cell function to promote TH2 responses via CCL17 production. Objectives To elucidate the mechanisms involved in allergen-specific T cell-induced LAR and recruitment of CD4+ T cells by examining the effects of T cell-derived factors on the induction of TSLP in primary bronchial epithelial cells ( PBEC). Methods PBEC grown at air-liquid interface from healthy individuals and patients with asthma were stimulated with double-stranded RNA (ds RNA) or supernatants from activated allergen-specific T cells. TSLP was measured in PBEC culture supernatants. Neutralizing antibodies and signalling inhibitors were used to examine the mechanisms responsible for the induction of epithelial-derived TSLP. The functional activity of PBEC-derived TSLP was measured using a bioassay involving the induction of CCL17 production from monocyte-derived dendritic cells (mo DC). Results Both ds RNA and allergen-specific T cells induced enhanced TSLP secretion from asthmatic PBEC compared to healthy PBEC. Activated PBEC culture supernatant induced TSLP-dependent CCL17 production from mo DC in a manner related to clinical asthmatic status. IL-1β, IL-6, and CXCL8, rather than TH2 cytokines ( IL-4/5/13), appeared to be the principle mediators of allergen-specific T cell-dependent induction of epithelial-derived TSLP, which was regulated by the MEK, MAPK, and NFκB pathways. Conclusion and Clinical Relevance Our data reveal a novel effect of allergen-specific T cells as a positive regulator of TSLP production by epithelial cells, suggesting T cell-airway epithelium interactions that may lead to maintenance and amplification of allergic inflammation. TSLP is currently a candidate for therapeutic intervention in asthma, but the factors that drive TSLP expression ( T cell-derived factors) may be equally relevant in the treatment of allergic inflammation. [ABSTRACT FROM AUTHOR]

Background Hematopoietic progenitor cells, especially those committed to the Eo/ B lineage, are known to contribute to allergic inflammation. Objective The aim of the present study was to investigate whether environmental factors are associated with changes in numbers of circulating Eo/ B progenitors at 1 year of age. Methods Peripheral blood from 60 1-year-old children enrolled in the LINA (Lifestyle and environmental factors and their Influence on Newborns Allergy risk) birth cohort was assessed for Eo/ B progenitor cells ( Eo/ B CFU) using standardized and validated methylcellulose assays. Frozen peripheral blood mononuclear cells ( PBMC) were cultured in the presence of IL-3, IL-5 or GM- CSF, and Eo/ B CFUs enumerated. Clinical outcomes and exposure to environmental tobacco smoke ( ETS) were documented by standardized questionnaires, and indoor volatile organic compound ( VOC) concentrations were assessed by passive sampling. Results Children with skin manifestations (atopic dermatitis or cradle cap) within the first year of life had higher numbers of circulating IL-3-, IL-5- or GM- CSF-stimulated Eo/ B CFUs ( P < 0.05) at 1 year. In children with cradle cap, a positive correlation was found between Eo/ B CFUs and exposure to ETS-related VOCs during pregnancy or at 1 year of age ( P < 0.05). Conclusions and Clinical Relevance This is the first demonstration that environmental exposures are positively associated with levels of circulating Eo/ B progenitors. The recruitment and differentiation of Eo/ B progenitors in response to environmental triggers may play a role in the development of skin manifestations during the first year of life. [ABSTRACT FROM AUTHOR]

Allergic rhinitis is a major chronic respiratory disease because of its prevalence, impacts on quality of life and work/school performance, economic burden, and links with asthma. Family doctors (also known as ‘primary care physicians’ or ‘general practitioners’) play a major role in the management of allergic rhinitis as they make the diagnosis, start the treatment, give the relevant information, and monitor most of the patients. Disease management that follows evidence-based practice guidelines yields better patient results, but such guidelines are often complicated and may recommend the use of resources not available in the family practice setting. A joint expert panel of the World Organization of Family Doctors (Wonca), the International Primary Care Airways Group (IPAG) and the International Primary Care Respiratory Group (IPCRG), offers support to family doctors worldwide by distilling the globally accepted, evidence-based recommendations from the Allergic Rhinitis and its Impact on Asthma (ARIA) initiative into this brief reference guide. This guide provides tools intended to supplement a thorough history taking and the clinician’s professional judgment in order to provide the best possible care for patients with allergic rhinitis. A diagnostic Questionnaire specifically focuses the physician’s attention on key symptoms and markers of the disease. When questionnaire responses suggest a diagnosis of allergic rhinitis, a Diagnosis Guide and a simple flowchart then lead the clinician through a series of investigations commonly available in primary care to support the diagnosis. In addition, key aspects of differential diagnosis are illuminated. According to ARIA, allergic rhinitis may be classified as Intermittent or Persistent, and as Mild or Moderate/Severe. The classification of rhinitis determines the treatment necessary, as set out in an ARIA flowchart included in this guide. The guide also includes information about the strength of evidence for efficacy of certain rhinitis treatments, a brief discussion of pediatric aspects, and a glossary of allergic rhinitis medications to assist the clinician in making medication choices for each individual patient. Finally, many patients with allergic rhinitis also have concomitant asthma, and this must be checked. The World Organization of Family Doctors has been delegated by WHO as the group that will be taking primary responsibility for education about chronic respiratory diseases among primary care physicians globally. This document will be a major resource in this educational program. [ABSTRACT FROM AUTHOR]

The article presents information on allergic rhinitis and its impact on asthma (ARIA). It informs that allergic rhinitis is a symptomatic disorder of the nose which is induced when exposed to allergen by an immunoglobulin E-mediated inflammation of the membranes lining the nose. It is noted that allergic rhinitis is a global health problem and the World Health Organization in the ARIA workshop updated guidelines concerning the disorder.

To evaluate the effect of a single nasal allergen challenge on peripheral blood eosinophil/basophil (Eo/B) progenitor cells and induced sputum eosinophil counts in subjects with allergic rhinitis.Sixteen adults entered a sequential nasal control and allergen challenge study, outside the pollen season. Blind assessment of peripheral blood Eo/B progenitor colony forming units (CFU), induced sputum and nasal lavage cell counts was made before and 24 h after both challenges. Subjects recorded their rhinitis symptoms and nasal peak inspiratory flow, hourly at home, following both challenges.When comparing the values 24 h after the control vs. the allergen challenge, there were no significant differences in Eo/B progenitor CFU (control (mean, SD): 3.6 (1.0)/106 cells; allergen: 4.4 (1.1)/106 cells) or sputum eosinophils (control (median, inter-quartile range): 1.0 (0.3–1.7)%; allergen: 0.7 (0.0–1.3)%) despite a significant increase in the percentage (median (inter-quartile range) of eosinophils in nasal lavage (control: 0.6 (0.1–0.9)%; allergen; 1.9 (0.9–8.1)% and significant worsening of nasal peak inspiratory flow and rhinitis symptoms.Despite a significant increase in nasal symptoms and lavage eosinophil counts, a single nasal allergen challenge was not sufficient to elicit a measurable haemopoietic response in circulation, or an increase in sputum eosinophil counts. [ABSTRACT FROM AUTHOR]

Increasing levels of proinflammatory cells, including eosinophils and basophils, are seen at the site of allergen challenge in allergic disease of the airways. Mechanisms for the recruitment of these cell types could involve either specific upregulation of adhesion molecule and chemoattraction, or the initiation of proliferation and differentiation of inflammatory cell progenitors derived from the bone marrow. In this study, we demonstrate, in two systems of eosinophilic–basophilic lineage-committed granulocytes of relative immaturity, that eosinophilic differentiation in vivo implies the induction of a distinct adhesion phenotype, characterized by the upregulation of β 7 integrin and downregulation of β 1 and α 5 integrins. Moreover, the eosinophilic differentiation induced an upregulation of complement receptor type 1 and type 3, and the expression was further enhanced upon a short-course in vitro activation with ionomycin. These data indicate a sequential alteration of disparate members of the integrin family during eosinophilic–basophilic differentiation, which may attribute to specific adhesion requirements at distinct stages of cell maturation. [ABSTRACT FROM AUTHOR]

Summary Eosinophils elaborate a number of proinflammatory mediators, including immunoregulatory cytokines and chemokines. Interleukin (IL)-4 and RANTES are important cytokines that have previously been shown to be expressed by mature eosinophils. We hypothesized that de novo synthesis of IL-4 and RANTES occurs in nascent eosinophils, leading to storage of newly produced proteins in crystalloid granule-like structures. Cytokine mRNA and protein expression were examined in cultured eosinophil colonies, which were derived from purified cord blood CD34+ cells and generated in semisolid media (methylcellulose) in the presence of recombinant human (rh)IL-3 and rhIL-5. Cytokine mRNA profiles were analysed by the reverse transcription–polymerase chain reaction (RT–PCR) to determine transcription of IL-4 and RANTES in cells on days 0, 7, 14, 21 and 28 of culture. The expression of translated cytokine products and granule major basic protein (MBP) was confirmed, from day 23 onwards, for colonies cultured in semisolid media, by immunofluorescent labelling and confocal laser-scanning microscopy (CLSM). We found that mRNA sequences encoding IL-4 and RANTES were expressed in freshly prepared, non-differentiated CD34+ cells. Furthermore, RANTES mRNA localized to carbol chromotrope 2R-positive colony cells, as assessed using in situ RT–PCR on day 21 of culture in semisolid media, and was found to gradually decrease (relative to β2-microglobulin) in rhIL-3- and rhIL-5-treated colony cells (comprising > 90% eosinophil-like cells) up to day 28. Immunoreactivity for IL-4 and RANTES co-localized with MBP in maturing colony eosinophils on day 23 of culture in semisolid media, as judged by CLSM. These results suggest that synthesis and storage of immunoregulatory cytokines, essential for processes associated with adaptive immunity, occurs in nascent eosinophils during their growth and differentiation. [ABSTRACT FROM AUTHOR]

Background: The sequence of adhesion-molecule expression during eosinophil differentiation remains unclear. Methods: We analyzed the surface expression of α4, β1, and β7 integrins and compared it to established myeloid developmental markers, using the eosinophilic cell line HL-60 clone 15, as well as cord and peripheral blood differentiation assays. Results: Cells induced to eosinophil differentiation by treatment with butyric acid, IL-5, and GM-CSF showed a significant upregulation of β7 integrin expression coincident with a marked upregulation of CD35 and attenuation of CD33 and β1 integrin expression. In addition, adhesion of induced HL-60 clone 15 cells to fibronectin was attenuated by a β7 integrin antibody. Conclusions: Our data show that protein synthesis-dependent upregulation of the functional β7 integrin occurs under conditions when α4 and β1 integrins are fully expressed, indicating a sequential appearance of specific adhesion molecules on differentiating eosinophil progenitors. [ABSTRACT FROM AUTHOR]

The purpose of this study was to examine airway responsiveness, sputum cells and the effects of inhaled corticosteroid in the chronic cough syndrome associated with eosinophilic bronchitis. We studied nine consecutive referrals with chronic cough, sputum with >10% eosinophils, normal spirometry, and normal methacholine airway responsiveness. Clinical assessment, sputum analysis, allergy skin tests and a methacholine inhalation test were performed at the first visit. Peak expiratory flow (PEF) was measured twice daily for 1 week followed by an adenosine monophosphate (AMP) inhalation test. Subjects were then treated with inhaled beclomethasone 0-4 mg twice daily for 7 days. Sputum analysis and measurement of methacholine responsiveness were then repeated. Excessive airway narrowing to methacholine was not present in any of the subjects. A methacholine plateau response was present in five subjects. Hyperresponsiveness to AMP was absent in six of the nine subjects, and PEF variability was not increased for eight subjects. Corticosteroid therapy led to a reduction in sputum eosinophil counts from 40.1 (SD 21.4)% to 4.0 (4.5)% but there was no significant change in metachromatic cell counts (0.8 SD 0.5% vs 0.6 SD 0.6%) or total cell counts. Methacholine responsiveness improved within the normal range in the three subjects in whom it could be determined. Chronic cough associated with eosinophilic airway inflammation can occur in the absence of variable airflow obstruction (asthma) and can improve after treatment with inhaled corticosteroid. This treatment can reduce the level of methacholine responsiveness within the normal range and reduces sputum eosinophils but not mast cells. These results suggest that the occurrence of variable airflow obstruction depends on the baseline level of methacholine responsiveness, the degree of eosinophilic infiltration and the degree to which methacholine responsiveness becomes heightened. [ABSTRACT FROM AUTHOR]

This study evaluated a research method to examine an exacerbation of asthma induced by corticosteroid withdrawal. Ten non-smoking adult asthmatics who were stable on treatment with inhaled steroid underwent a graded reduction of the daily dose by 200 pg at weekly intervals until an exacerbation of symptoms occurred. A daily symptom, peak expiratory flow rate (PEF) and medication diary was kept. Weekly clinic visits were used to assess symptoms, spirometry, methacholine airway responsiveness (expressed as the provocative concentration to cause a fall in FEV1 of 20%,PC20), circulating eosinophils, basophils and their progenitors (Eo/B-CFU), and sputum inflammatory cells. The laboratory tests were performed blind to the clinical details. Each subject developed an exacerbation of symptoms, on average at 16 (7-26) days after the onset of steroid reduction. This was accompanied by a deterioration in each of the objective measures. There was a fall in FEV, by 320 ml (s.e.m. 95) and in PC20 from 0.8 to 0.43 mg/ml. Circulating eosinophils rose from 114 (24) × 10³/ml to 227 (50) × 10³/ml and Eo/B-CFU rose from 31 (5.6) to 44 (11.3)/106 cells. Sputum developed in five subjects and contained 36 (5.2)% eosinophils and 1.98 (0.21)% metachromatic cells (mast cells or basophils). The symptom diary and weekly questionaire were demonstrated to be valid and responsive to change. A deterioration indicated by the daily symptom score preceded changes in PEF. Treatment by an increase in steroid was followed by reversal of each of the changes. We conclude that this research method can safely produce and examine a mild exacerbation of asthma, and that an increase in airway inflammation is an early feature. [ABSTRACT FROM AUTHOR]

Circulating eosinophils, basophils and eosinophil/basophil (Eo/B) progenitors were examined in 12 patients at the time of an exacerbation of asthma accompanied by sputum eosinophilia and after resolution of the exacerbation with inhaled corticosteroid treatment. Differential counts were performed and peripheral blood non-adherent mononuclear cells were cultured for 14 days in methyl-cellulose to determine the number of Eo/B and granulocyte-macrophage (GM) colonies without knowledge of the clinical conditions or findings. With resolution of the asthma exacerbation on beclomethasone therapy, there were significant falls in circulating eosinophils, basophils and Eo/B colonies whereas GM colonies were unchanged. To elucidate whether the observed changes could be due to systemic absorption or local action of inhaled corticosteroid. seven subjects with allergic rhinitis and no current evidence of lower airway inflammation (no symptoms of asthma and normal methacholine airway responsiveness) received 14 days' treatment with the same dose of inhaled beclomethasone or of placebo in a double-blind randomized cross-over study. No significant changes in airway function or in circulating cell counts were observed. The results suggest reduced production of eosinophils and basophils after the resolution of an exacerbation of asthma. This effect may be due to reduced levels of airway-derived eosinophil basophil growth and differentiation factors. [ABSTRACT FROM AUTHOR]

The development of FcR∊-bearing histamine-containing basophilic cells was studied in cultures of peripheral blood leucocytes and bone marrow leucocytes from normal individuals. The determination of basophilic cells was performed blindly. Before cultivation there were fairly similar numbers of basophilic cells in the samples from the three different sources (1.6 ± 1.6 n= 13; 1.4 ± 2.0 n=21; 4.3 ± 4.7 n =8, respectively). During cultivation, spontaneously appearing large blast-like basophilic cells were seen in good correspondence with a formation of histamine in the cultures (Spearman rank correlation coefficient = 0.9135, n = 13. P < 0.001). This was more accentuated with bone marrow cells than with peripheral blood and cord blood cells. Conditioned medium (CM) was prepared from cells isolated from various tissues and stimulated by different means, e.g. peripheral blood from atopic individuals stimulated with allergen and unstimulated tonsil cells. Addition of the CM resulted in increased development of histamine-containing basophilic cells. Optimum stimulation was achieved with 10% CM. The basophilic stimulation by CM, as assessed as indices vs. unstimulated cultures, was more accentuated in cultures of peripheral blood cells than of bone marrow and cord blood cells (2.8 ± 1.2; 1.8 ± 0.5; 2.0 ± 0.4, respectively). In contrast, the histamine formation was particularly evident in stimulated cultures of bone marrow cells, where more than four-fold increases of histamine were found. In bone marrow cells the histamine levels per basophilic cell also increased, whereas this was not the case in cord blood cells. A pronounced development of basophilic cells was achieved when using leukoagglutinin, provided the mitogen in the CM was eliminated. The formation of basophilic cells was prevented with mitomycin c and cycloheximide. in conclusion, the system described may provide important information on the development of histamine-containing basophilic cells at various maturation stages from different compartments, and mechanisms in a developing atopic disease. [ABSTRACT FROM AUTHOR]