Adherence to inhaled corticosteroids and long-acting β2-agonists in asthma: A MASK-air study

INTRODUCTION

Adherence to controller medication is a major problem in asthma management, being difficult to assess and tackle. mHealth apps can be used to assess adherence. We aimed to assess the adherence to inhaled corticosteroids+long-acting β2-agonists (ICS+LABA) in users of the MASK-air® app, comparing the adherence to ICS+formoterol (ICS+F) with that to ICS+other LABA.

MATERIALS AND METHODS

We analysed complete weeks of MASK-air® data (2015-2022; 27 countries) from patients with self-reported asthma and ICS+LABA use. We compared patients reporting ICS+F versus ICS+other LABA on adherence levels, symptoms and symptom-medication scores. We built regression models to assess whether adherence to ICS+LABA was associated with asthma control or short-acting beta-agonist (SABA) use. Sensitivity analyses were performed considering the weeks with no more than one missing day.

RESULTS

In 2598 ICS+LABA users, 621 (23.9%) reported 4824 complete weeks and 866 (33.3%) reported weeks with at most one missing day. Higher adherence (use of medication ≥80% of weekly days) was observed for ICS+other LABA (75.1%) when compared to ICS+F (59.3%), despite both groups displaying similar asthma control and work productivity. The ICS+other LABA group was associated with more days of SABA use than the ICS+F group (median=71.4% versus 57.1% days). Each additional weekly day of ICS+F use was associated with a 4.1% less risk in weekly SABA use (95%CI=-6.5;-1.6%;p=0.001). For ICS+other LABA, the percentage was 8.2 (95%CI=-11.6;-5.0%;p<0.001).

CONCLUSIONS

In asthma patients adherent to the MASK-air app, adherence to ICS+LABA was high. ICS+F users reported lower adherence but also a lower SABA use and a similar level of control.

Rhinitis associated with asthma is distinct from rhinitis alone: The ARIA-MeDALL hypothesis

Asthma, rhinitis and atopic dermatitis (AD) are interrelated clinical phenotypes that partly overlap in the human interactome. The concept of "one-airway-one-disease", coined over 20 years ago, is a simplistic approach of the links between upper- and lower-airway allergic diseases. With new data, it is time to reassess the concept. This article reviews (i) the clinical observations that led to Allergic Rhinitis and its Impact on Asthma (ARIA), (ii) new insights into polysensitisation and multimorbidity, (iii) advances in mHealth for novel phenotype definition, (iv) confirmation in canonical epidemiologic studies, (v) genomic findings, (vi) treatment approaches and (vii) novel concepts on the onset of rhinitis and multimorbidity. One recent concept, bringing together upper- and lower-airway allergic diseases with skin, gut and neuropsychiatric multimorbidities, is the "Epithelial Barrier Hypothesis". This review determined that the "one-airway-one-disease" concept does not always hold true and that several phenotypes of disease can be defined. These phenotypes include an extreme "allergic" (asthma) phenotype combining asthma, rhinitis and conjunctivitis. Rhinitis alone and rhinitis and asthma multimorbidity represent two distinct diseases with the following differences: (i) genomic and transcriptomic background (Toll-Like Receptors and IL-17 for rhinitis alone as a local disease; IL-33 and IL-5 for allergic and non-allergic multimorbidity as a systemic disease), (ii) allergen sensitisation patterns (mono- or pauci-sensitisation versus polysensitisation), (iii) severity of symptoms and (iv) treatment response. In conclusion, rhinitis alone (local disease) and rhinitis with asthma multimorbidity (systemic disease) should be considered as two distinct diseases, possibly modulated by the microbiome, and may be a model for understanding the epidemics of chronic and auto-immune diseases.

The prevalence of sleep impairments and predictors of sleep quality among patients with asthma

BACKGROUND

Sleep is a significant dimension of daily life. However, only a few studies have examined the sleep quality of asthmatics in a real-world clinical settings.

OBJECTIVE

This study is aimed to estimate the prevalence of sleep impairments among asthmatic patients and examine the relationship between sleep quality, asthma control, rhinitis symptoms, and sociodemographic characteristics.

METHODS

The present study adopted the observational cross-sectional research design that has been designed by the Italian Respiratory Society and used valid assessments to measure the study variables.

RESULTS

Data from 1150 asthmatic patients (mean age 51.01 years ± 16.03) were subjected to analysis. 58.3% of the patients had impaired sleep quality (Pittsburgh Sleep Quality Index [PSQI] total scores > 5), and their mean PSQI score was 5.68 (SD = 3.4). A significant correlation emerged between sleep quality and asthma control (p = 0.0001) and a significant albeit weak correlation emerged between PSQI total scores and Total 5 Symptoms Score (r = 0.24, p = 0.0001). Sleep quality was significantly associated health-related quality of life [HRQoL]. (r = 0.50, p < 0.001). After exclusion of patients at risk for Obstructive Sleep Apnea Syndrome (OSAS) and Gastro Esophageal Reflux Disease (GERD), the most important determinants of PSQI score were HRQoL, In the entire sample asthma control is the strongest predictor of both sleep quality and HRQoL.

CONCLUSIONS

The results of this real-world study highlight the prevalence, impact and predictors of sleep disturbances in asthmatic patients and suggest the need for physicians to detect poor sleep quality.

Public Prevention Plans to Manage Climate Change and Respiratory Allergic Diseases. Innovative Models Used in Campania Region (Italy): The Twinning Aria Implementation and the Allergy Safe Tree Decalogue

In recent years, climate change has been influenced by air pollution, and this destructive combination has justifiably sounded an alarm for nations and many institutional bodies worldwide. Official reports state that the emission of greenhouse gases produced by human activity are growing, and consequently also the average temperature. The World Health Organization (WHO) believes that health effects expected in the future due to climate change will be dramatic, and has invited international groups to investigate potential remedies. A task force has been established by the Italian Society of Allergology, Asthma and Clinical Immunology (SIAAIC), with the aim to actively work on correlation between pollution and climate change. The Task Force provided prevention tools to suggest city leaders how to improve the health conditions of allergic people in public urban parks. The "Allergy Safe Tree Decalogue" suggests the preparation and maintenance of public low allergy-impact greenery. Through the Twinning ARIA project, the Division for the Promotion and Enhancement of Health Innovation Programs of Campania Region (Italy), sought to promote the implementation of the project in the regional Health System. The main objective will be to investigate the current use and usefulness of mobile phone Apps in the management of allergic respiratory disease, through Mobile Airways Sentinel networK (MASK), the Phase 3 of the ARIA initiative, based on the freely available MASK App (the Allergy Diary, Android and iOS platforms). The effects of these prevention activities will be registered and compared with monitoring efforts thanks to the Aerobiology Units, located throughout the Campania area. A joint effort between researchers and public administrations for the implementation of prevention plans coherently with the two models proposed in a specific area, i.e. the Decalogue for public administrations and the MASK Allergy Diary app for individual patients suffering from allergy, will be implemented as a pilot.

Hymenoptera Venom Allergy: Management of Children and Adults in Clinical Practice

Hymenoptera venom allergy is an epidemiologically underestimated condition and a major cause of morbidity worldwide. Preventing future allergic reactions in patients who experience a systemic reaction is based on the correct management of the emergency followed by an accurate diagnosis, prescription of adrenaline autoinjectors, and, where indicated, specific venom immunotherapy. Some epidemiological studies highlight our poor knowledge of this disease and the frequent inadequacy of its management. Moreover, they emphasize the importance of such a life-saving treatment as specific immunotherapy. The availability of high-quality hymenoptera venom extracts for diagnostic and therapeutic use has dramatically improved the prognosis and quality of life of allergic patients. Subcutaneous venom immunotherapy is currently the most effective form of allergen-based immunotherapy, with a carry-over effect lasting up to several years after its interruption. This report on the management of hymenoptera venom-allergic children and adults was prepared by a panel of Italian experts. The main objective of this consensus document is to review the scientific evidence related to diagnosis, therapy, and management of patients allergic to hymenoptera venom. Thus, we can improve our knowledge of the disease and promote good clinical practices. The present document provides practical suggestions for correct diagnosis, prescription of emergency therapy and immunotherapy, and strategies for patient care.

Clinical approach on challenge and desensitization procedures with aspirin in patients with ischemic heart disease and nonsteroidal anti-inflammatory drug hypersensitivity

BACKGROUND

Hypersensitivity to acetylsalicylic acid (ASA) constitutes a serious problem for subjects with coronary artery disease. In such subjects, physicians have to choose the more appropriate procedure between challenge and desensitization. As the literature on this issue is sparse, this study aimed to establish in these subjects clinical criteria for eligibility for an ASA challenge and/or desensitization.

METHODS

Collection and analysis of data on ASA challenges and desensitizations from 10 allergy centers, as well as consensus among the related physicians and an expert panel.

RESULTS

Altogether, 310 subjects were assessed; 217 had histories of urticaria/angioedema, 50 of anaphylaxis, 26 of nonimmediate cutaneous eruptions, and 17 of bronchospasm related to ASA/nonsteroidal anti-inflammatory drugs (NSAID) intake. Specifically, 119 subjects had index reactions to ASA doses lower than 300 mg. Of the 310 subjects, 138 had an acute coronary syndrome (ACS), 101 of whom underwent desensitizations, whereas 172 suffered from a chronic ischemic heart disease (CIHD), 126 of whom underwent challenges. Overall, 163 subjects underwent challenges and 147 subjects underwent desensitizations; 86 of the latter had index reactions to ASA doses of 300 mg or less. Ten subjects reacted to challenges, seven at doses up to 500 mg, three at a cumulative dose of 110 mg. The desensitization failure rate was 1.4%.

CONCLUSIONS

In patients with stable CIHD and histories of nonsevere hypersensitivity reactions to ASA/NSAIDs, an ASA challenge is advisable. Patients with an ACS and histories of hypersensitivity reactions to ASA, especially following doses lower than 100 mg, should directly undergo desensitization.

Self-medication of anaphylactic reactions due to Hymenoptera stings-an EAACI Task Force Consensus Statement

An anaphylactic reaction due to a Hymenoptera sting is a clinical emergency, and patients, their caregivers as well as all healthcare professionals should be familiar with its recognition and acute management. This consensus report has been prepared by a European expert panel of the EAACI Interest Group of Insect Venom Hypersensitivity. It is targeted at allergists, clinical immunologists, internal medicine specialists, pediatricians, general practitioners, emergency department doctors, and any other healthcare professional involved. The aim was to report the scientific evidence on self-medication of anaphylactic reactions due to Hymenoptera stings, to inform healthcare staff about appropriate patient self-management of sting reactions, to propose indications for the prescription of an adrenaline auto-injector (AAI), and to discuss other forms of medication. First-line treatment for Hymenoptera sting anaphylaxis is intramuscular adrenaline. Prescription of AAIs is mandatory in the case of venom-allergic patients who suffer from mast cell diseases or with an elevated baseline serum tryptase level and in untreated patients with a history of a systemic reaction involving at least two different organ systems. AAI prescription should also be considered in other specific situations before, during, and after stopping venom immunotherapy.

Asymmetric dimethylarginine (ADMA): will be or will not be a new revolutionary biomarker of bronchial asthma

Carraro et al. measured asymmetric dimethylarginine (ADMA) in the exhaled breath condensate (EBC) obtained from children with asthma and from healthy subjects. The authors demonstrated higher levels of ADMA in EBC of asthmatics compared to controls. ADMA levels in EBC did not correlate with serum levels, lung function parameters, and fractional exhaled nitric oxide. ADMA levels in EBC did not significantly differ between asthmatic patients regularly treated with inhaled steroids and those who were steroid naïve. Further studies are necessary in order to evaluate the role of this biomarker in the characterization of phenotypes of severe bronchial asthma.

Asymmetric dimethylarginine (ADMA): will be or will not be a new revolutionary biomarker of bronchial asthma?

Carraro et al. measured asymmetric dimethylarginine (ADMA) in the exhaled breath condensate (EBC) obtained from children with asthma and from healthy subjects. The authors demonstrated higher levels of ADMA in EBC of asthmatics compared to controls. ADMA levels in EBC did not correlate with serum levels, lung function parameters, and fractional exhaled nitric oxide. ADMA levels in EBC did not significantly differ between asthmatic patients regularly treated with inhaled steroids and those who were steroid naïve. Further studies are necessary in order to evaluate the role of this biomarker in the characterization of phenotypes of severe bronchial asthma.

Asthma is associated with increased susceptibility to infection

Asthma is a chronic inflammatory disorder of the airways characterized by airway hyperresponsiveness and airflow limitation. Despite respiratory symptoms may be episodic, progressive changes occur in the structure of the airway, leading to its irreversible remodeling. Changes include mucus hypersecretion, injury to epithelial cells, smooth muscle hypertrophy, sub-basement membrane fibrosis and angiogenesis. The risk factors for developing asthma are a combination of genetic predisposition along with environmental exposure to inhaled substances and particles that may provoke allergic reactions or irritate the airways, such as in- and out-door allergens, tobacco smoke, chemical irritants in the workplace and air pollution. Asthma is a clinically heterogeneous entity due to the complexity of its pathogenetic substrate. Recent evidence suggests asthma to be associated with a sort of immunodeficiency accounting for an increased susceptibility to infection in asthmatic patients. The role of infections as triggers and promoters of disease progression is well established. Conversely, the impact of asthma as a predisposing condition to infection has not clearly been addressed. Such a topic will be the focus of the present review.

Bronchoscopy in sarcoidosis: union is strength

Sarcoidosis is a benign disease of unknown etiology that is characterized by the formation of noncaseating epithelioid cell granulomas. Although a multisystemic disease, it primarily affects the lung and the lymphatic system of the body. When a histological diagnosis is required, bronchoscopy is frequently employed because allows tissue sampling from several anatomic sources, such as airways, lung parenchyma and hilar/mediastinal nodes. Transbronchial lung biopsies (TBLB), endobronchial biopsies (EBB) and conventional transbronchial needle aspiration (cTBNA) have long been the only bronchoscopic techniques to diagnose sarcoid granulomas, until the advent of endobronchial ultrasound guided needle aspiration (EBUS-TBNA). This technique shows excellent yield in sampling mediastinal adenopathies with a higher sensitivity than the conventional technique in sarcoidosis as well. Furthermore, non controlled studies, demonstrated its diagnostic superiority than EBB and TBLB in stages I (hilar adenopathies only) and II (hilar lymph nodes and parenchymal infiltrations) thoracic sarcoidosis. In a recent study, Gupta et al., randomized 130 patients with suspected stage I and II disease to undergo EBUS-TBNA or cTBNA in conjunction with transbronchial and endobronchial biopsies. The Authors demonstrated that the yield of cTBNA added to EBB and TBLB is similar to EBUS-TBNA plus transbronchial biopsies, although ultrasound guided transbronchial needle aspiration shows the best single diagnostic efficacy. In this review article we aimed to discuss the findings by Gupta in the context of medical literature, highlighting the importance of adding nodal aspirations (with or without ultrasound guidance) with bronchial and transbronchial samples to gain the optimal sensitivity in obtaining histological confirmation. We finally pointed out the need for future studies to evaluate the potential role of rapid on-site evaluation (ROSE) of needle aspirates in reducing additional sampling and related costs and complications.

Spirometric criteria to diagnose airway obstruction in the elderly: fixed ratio vs lower limit of normal

COPD is the most common chronic lung disease. It becomes more prevalent with increasing age but remains under-diagnosed in the elderly. A heated debate concerns the most suitable way to diagnose airway obstruction in this age group. Most COPD guidelines recommend to use a FEV1/FVC of 0.70 as threshold to define an obstructive ventilatory defect. While the use of a 0.70 ratio may be simple, it may result in under-diagnosis of airflow obstruction in young people and over-diagnosis in the elderly due to an age-related decline in pulmonary volumes, especially in FEV1. This might lead to unnecessary use of medications and increased risk of adverse effects. A proposed strategy for reducing the misclassification of airway obstruction include the use of the statistically derived lower limit of normal (LLN) for FEV1/FVC, calculated as the fifth percentile of the normal distribution in a healthy population. Some authors addressed the possibility to evaluate lung function through high-resolution CT. In contrast to spirometry, CT imaging may allow for regional assessment of the compartments involved (airways, parenchyma, vasculature), and may enable a phenotype-driven characterization of COPD. Bhatt et al. recently observed that a small proportion (7%) of subjects with CT-defined emphysema were identified by the 0.70 threshold for FEV1/FVC but not by the LLN. However, there is no evidence that CT-emphysema corresponds to a clinical entity that can benefit by inhaled therapy. Further studies are needed to assess the classificatory and prognostic value of the different proposed criteria to diagnose airway obstruction in the elderly.

Is mild asthma in real life always in the Green Zone?

Asthma is a chronic inflammatory disease of the airways that is characterized by variable narrowing of the airways and symptoms of intermittent dyspnea, wheezing, and nighttime or early-morning coughing. Asthma is a major health problem throughout the world, affecting an estimated 315 million persons of all ages. Asthma is clinically heterogeneous, and its pathophysiology is complex. For convenience, asthma action plans are often broken down into three zones, usually based on peak flow meter recordings: green, yellow, and red according to the level of lung function impairment. Recent evidence shows that every asthmatic is potentially at risk for severe exacerbation independently of his/her zone, including the green zone. Furthermore, in real life scenario asthmatic patients can have poor perception of their symptoms or/and overestimate their level of asthma control, and this can obviously confound the clinical picture and favor sudden worsening of symptoms. To understand how to treat these patients, as well as how to assess their future risk, can make a difference in terms of clinical outcomes and prognosis. Following the suggestions and concerns recently published, who recently focused on the clinical management of mild asthma, we aimed at exploring strengthens and gaps in the daily management of the mildest forms of the disease, with a focus on alternative diagnostic and therapeutic strategies in approaching the "green" patient in clinical practice.

Bronchial thermoplasty in severe asthma: food for thoughts

Asthma is a complex inflammatory disorder of the airways characterized by airway hyper-responsiveness and variable, reversible, airflow obstruction. Bronchial thermoplasty (BT) is a new modality for treating asthma. It targets airway smooth muscles (ASM) by delivering a controlled specific amount of thermal energy (radiofrequency ablation) to the airway wall through a dedicated catheter. The use of bronchial thermoplasty has been widely discussed for its potential in the treatment of asthma, since it seems to be able to reduce the symptoms of asthma. The definitive study for BT (AIR2 trial) employed a randomized, double-blind, sham-controlled design and enrolled 288 subjects with severe persistent asthma from 30 US and international centers. The results of the AIR2 trial demonstrated clinically significant benefits of BT compared with the sham group at one year post-treatment, including an improvement in asthma-related quality of life, 32% reduction in severe exacerbations, 84% reduction in emergency department visits for asthma symptoms, and a 66% reduction in time lost from work/school/other daily activities because of asthma symptoms. Preclinical work showed that ASM is reduced after BT by at least 3 years after treatment. The recent article from the ARI2 trial study group analyses the long-term safety and effectiveness of BT in patients with severe persistent asthma and demonstrates the 5-year durability of the benefits of BT in the control of symptoms and safety. It supports the evidence that reduction in asthma attacks, ER visits, and hospitalizations for respiratory symptoms are maintained for at least 5 years. There is a pressing need to understand the underlying mechanism(s) of BT and how the delivered heat is translated into clinical benefit. This necessitates additional investigation to identify disease and patient characteristics that would enable accurate phenotyping of positive responders to avoid unnecessary procedures and risks.

The adhesion molecule ICAM-1 is overexpressed in patients with Hymenoptera venom allergy and decreases after ultrarush venom immunotherapy

Adhesion molecules, including ICAM-1, are an important factor in allergic inflammation caused by inhalant allergens, but there are no studies investigating their possible role in Hymenoptera venom allergy (HVA). We measured the level of ICAM-1 in 13 venom-allergic patients before and after ultra-rush venom immunotherapy (VIT). Eight patients were treated by yellow jacket venom and 5 were treated by honeybee venom. Serum ICAM-1 levels were assayed by an immunoenzymatic method, with a detection limit of 0.35 ng/ml. The mean level of ICAM-1 changed from 316.4±78.2 ng/ml before VIT to 294.7±77.9 after VIT. This difference was statistically significant (p = 0.019). These findings show that in patients with HVA there is an over-expression of ICAM-1, and that ultra-rush VIT significantly decreases ICAM-1 levels. It is likely that the known ability of VIT to correct the imbalance in T lymphocytes subpopulations and in the associated production of cytokines may account for this observation. In fact, such cytokines include IL-4 and TNF-alpha, that up-regulate adhesion molecules.

Heterotopic ossification after total hip arthroplasty: our experience

Heterotopic ossification is a condition characterized by the presence of mature lamellar bone and often bone marrow in soft tissues surrounding a major joint. It represents a common complication after total hip arthroplasty (THA). The etiology and predisposing factors are not completely known, but some authors reported that the implant of a non-cemented prosthesis seems to be associated with a greater incidence of HO. Two hundred and two non-cemented total hip arthroplasties were performed between October 1997 and February 2002. The mean age was 70.2 years. The average follow-up for 181 hips included in the study was 96 months (range, 72-120 months). A standard lateral approach (Hardinge) was performed for the implant of a non-cemented femoral component and a non-cemented acetabular component. Radiographs were done before and after surgery, at 1, 4 and 12 months postop, then every year. The incidence of HO was assessed in the antero-posterior view at each interval and graded according to Brooker classification. Out of 181 implants, HO was observed in 52 hips (28,7%). Heterotopic bone was graded as class I in 32 (17.7%) hips, class II in 14 (7.73%) hips, class III in 6 (3,3%) hips and class IV in none (0%). The mean preoperative Harris hip score was 48; at the last follow-up, the mean postoperative score was preoperatively to a mean of 89 points (range, 76-97 points) in HO Hip and of 91 points (range, 78-100 points) in the other Hip. In our experience, non-cemented THA led to a higher incidence of class I and II HO according to Brooker Classification, the incidence of HO is comparable to the rates reported in recent studies about the HO finding after a non-cemented THA, the importance of clinical symptoms in the presence of HO is very low.

A meta-analysis of open versus arthroscopic Bankart repair using suture anchors

Purpose of this study is to conduct a meta-analysis comparing the results of open and arthroscopic Bankart repair using suture anchors in recurrent traumatic anterior shoulder instability. Using Medline Pubmed, Cochrane and Embase databases we performed a search of all published articles. We included only studies that compared open and arthroscopic repair using suture anchors. Statistical analysis was performed using chi-square test. Six studies met the inclusion criteria. The total number of patients was 501, 234 suture anchors and 267 open. The rate of recurrent instability in the arthroscopic group was 6% versus 6.7% in the open group; rate of reoperation was 4.7% in the arthroscopic group vs. 6.6% in open (difference not statistically significant). The difference was statistically significant only in the studies after 2002 (2.9% of recurrence in the arthroscopic group vs. 9.2% in open; 2.2% of reoperation in the arthroscopic group vs. 9.2% in open). Results regarding function couldn't be combined because of non-homogeneous scores reported in the original articles, but the arthroscopic treatment led to better functional results. Arthroscopic repair using suture anchors results in similar redislocation and reoperation rate compared to open Bankart repair; however, we need larger and more homogeneous prospective studies to confirm these findings.

Extracorporeal shock waves increase interleukin-10 expression by human osteoarthritic and healthy osteoblasts in vitro

OBJECTIVE

Extra corporeal shock waves (ESW) have been proposed as additional therapy in bone fracture repair and osteoarthrtitis (OA). However, little is known on the effects of ESW on osteoblast metabolism. The aim of this study was to evaluate phenotype changes of healthy and OA human osteoblasts following ESW treatment.

METHODS

Osteoblasts were isolated from subchondral bone of 13 OA patients and 7 healthy donors. Osteoblasts were treated or not with ESW at different levels of energy and impulses. IL-10, TNF-alpha, CD29/Beta1 integrin, and CD105/endoglin expression was evaluated by flowcytometry.

RESULTS

Intracellular IL-10 significantly increased using 1000 impulses at 0.055 mJ/mm2 in both healthy and OA osteoblasts in comparison with untreated osteoblasts (p<0.01). Only in the OA osteoblasts CD29 and CD105 expression significantly increased at 500 impulses and 0.17 mJ/mm2 ESW treatment (p<0.05).

CONCLUSION

ESW are capable of modifying IL-10 expression in osteoblasts. There is evidence that IL-10 can play a role in bone remodelling by inhibiting osteoclast differentiation and this suggests that ESW may favour bone growth and healing. This further supports the use of ESW in treating bone fracture to promote callus formation. However, the possible use of ESW in OA therapy needs further studies since in OA, osteoblast metabolism is already enhanced with bone sclerosis and ESW application may further increase bone deposition and osteophyte formation, leading to a subsequent worsening of the disease.

Allergy and the cardiovascular system

The most dangerous and life-threatening manifestation of allergic diseases is anaphylaxis, a condition in which the cardiovascular system is responsible for the majority of clinical symptoms and for potentially fatal outcome. The heart is both a source and a target of chemical mediators released during allergic reactions. Mast cells are abundant in the human heart, where they are located predominantly around the adventitia of large coronary arteries and in close contact with the small intramural vessels. Cardiac mast cells can be activated by a variety of stimuli including allergens, complement factors, general anesthetics and muscle relaxants. Mediators released from immunologically activated human heart mast cells strongly influence ventricular function, cardiac rhythm and coronary artery tone. Histamine, cysteinyl leukotrienes and platelet-activating factor (PAF) exert negative inotropic effects and induce myocardial depression that contribute significantly to the pathogenesis of anaphylactic shock. Moreover, cardiac mast cells release chymase and renin that activates the angiotensin system locally, which further induces arteriolar vasoconstriction. The number and density of cardiac mast cells is increased in patients with ischaemic heart disease and dilated cardiomyopathies. This observation may help explain why these conditions are major risk factors for fatal anaphylaxis. A better understanding of the mechanisms involved in cardiac mast cell activation may lead to an improvement in prevention and treatment of systemic anaphylaxis.

[Functional analysis after Achilles tendon repair]

The Achilles tendon rupture (ATR) is a severe injury and requires a surgical treatment which can result in functional impairment, limiting unprofessional sports activities. In order to evaluate this potential impairment 20 subjects (SG) who had received surgical treatment for ATR and 20 healthy subjects (CG) were required to execute vertical jump according to counter movement jump and squat jump protocol. For both groups the flying time (Tv) of each foot has been acquired, adopting accelerometric transducers positioned posteriorly at the level of malleolar axis. The SG's Tv is significantly lesser than the CG's one, demonstrating an inferior global performance respect to healthy people and the operated leg has a Tv 6% higher than the contralateral, while in the CG there are no statistical difference between the Tv of the limbs. For seven operated subjects Tv values are lesser than threshold values obtained from CG. For them sports activity which implies high and cyclic stress on the lower limbs could be dangerous. Functional evaluation, consequently, allow to assess impairments not differently estimable.

[Manual lymph drainage of post-mastectomy "big arm"]

We estimate the effectiveness of the manual lymphodrainage in the patients with post-mastectomy lymphedema of the upper limb associated to axillary lymphnodes dissection of the ipsilateral arm. The best results were found in the patients with soft and recent lymphedema (which means that was seen within one year); the worst were found in the chronic hard lymphedema. An important psychological assistance and physiotherapy were required to complete the rehabilitation. However, the physiotherapy was very effective when associated to pressed bandage of the arm, at the end of the LDM therapy. Furthermore, the muscle contraction in the bandage had reinforced the lymphoematic pump effect.

Increased Bcl-2/p53 ratio in human osteoarthritic cartilage: a possible role in regulation of chondrocyte metabolism

OBJECTIVE

To determine whether Bcl-2, p53, and Fas/CD95 help to control cartilage metabolism.

METHODS

Six normal and 14 osteoarthritic (OA) cartilage samples were examined, and two zones from each sample showing the least (Min) and most (Max) anatomical damage were selected. Chondrocytes were isolated by sequential enzymatic digestion and freshly processed. Bcl-2, p53, and Fas/CD95 expression was evaluated by immunofluorescence and FACS analysis; the cell cycle was analysed using propidium iodide, and chondrocyte proliferation assessed by [(3)H]thymidine incorporation.

RESULTS

Intracellular levels of Bcl-2 were significantly higher in Max (27.5%) than in Min (21%, p<0.01) OA or normal chondrocytes (18.5%, p<0.01). Intracellular p53 expression was significantly decreased in Max (25.5%) compared with Min (37%, p<0.01) OA or normal cartilage (41.5%, p<0.05). Fas/CD95 receptor expression on surface chondrocytes did not significantly differ between OA and normal cartilage. Cell cycle analysis showed that the proportion of activated chondrocytes in the S phase was significantly higher in Max (69%) than in Min (49%) OA or normal cartilage (43%). The prevalence of proliferating chondrocytes progressively increased according to the degree of OA damage (mean (SEM) Min 1247 (260), Max 2423 (460), p<0.05). Chondrocyte [(3)H]thymidine uptake correlated positively with Bcl-2 (r(s) = 0.62, p = 0.009) and correlated inversely with p53 levels (r(s) = -0.55, p = 0.02).

CONCLUSIONS

Bcl-2 and p53 play a part in apoptosis, but also help to regulate chondrocyte growth and differentiation. Whereas Bcl-2 promotes cell survival, p53 can arrest cell cycle. The data confirm that chondrocyte activity is enhanced in OA and suggest that the increased Bcl-2/p53 ratio sustains the metabolic boost of chondrocytes.

Manipulative therapy in the treatment of benign cervicobrachialgia of mechanical origin

The authors compared two methods of rehabilitation, traditional physical therapy and manual therapy, in the treatment of benign cervicobrachialgia of mechanical origin, typical of young subjects, generally consequent to mild and moderate trauma, occasional strain or incorrect posture repeated in time. A MID (minor intervertebral deficit) is at its origin, characterized by the absence of objective instrumental signs (X-ray, CT scan, MRI) and it is only diagnosed based on clinical history and accurate physical examination of the spine segment involved. A sample of 80 patients was divided at random into two groups: the first group was submitted to traditional physiotherapy, the second to manipulative therapy carried out according to the French method of R. Meigne. The results obtained, which were evaluated by univaried ANOVA and Student's "t" test statistical analysis, showed the greater effectiveness of manipulative treatment, in the short term and in the long term.

Adhesion molecules in gonarthrosis and knee prosthesis aseptic loosening follow-up: possible therapeutic implications

The involvement of the synovium is common in phlogistic processes of various joint diseases. Apart from synoviocytes and the other cells in the synovial tissue, circulating cells recruited from peripheral blood also participate in the phlogistic process. The increased expression of adhesion molecules on both circulating and endothelial cell surface may further this recruitment. We studied 15 patients affected by serious gonarthrosis requiring a prosthetic implant (GPI) and 7 with knee prosthesis aseptic loosening (KPL) to evaluate adhesion molecule expression and phlogistic infiltration in the synovium using immunohistochemistry and microscopic analysis. As control we studied 10 subjects affected by degenerative meniscopathies undergoing a selective arthroscopic surgical meniscectomy. Analysis with Kruskal-Wallis test showed no statistical significant differences in the expression of CD54, CD11a, CD11b and CD18 in three groups examined. The model of variance analysis (Friedman test), showed that CD54 expression is greater in patients with GPI and KPL in comparison with the other molecules. Adhesion molecules and their functions are important in arthropathies not only because their evaluation can allow us to identify the degree of inflammation and to predict its evolution, but also because pharmacological control of their expression could have important therapeutic implications.

Increased expression of nerve growth factor (NGF) and high affinity NGF receptor (p140 TrkA) in human osteoarthritic chondrocytes

OBJECTIVE

We aimed to investigate the expression of nerve growth factor (NGF) and high affinity NGF receptor (p140 TrkA) on chondrocytes from human healthy and osteoarthritic cartilage.

METHODS

We recruited 12 patients with osteoarthritis (OA) undergoing surgical knee replacement. Articular cartilage was split into two zones showing macroscopically and histologically the lowest (MIN) and highest (MAX) degree of osteoarthritic damage. Additional specimens of cartilage were obtained from three healthy donors. Chondrocytes were isolated by enzymatic digestion and freshly processed for NGF protein, Trk A detection and mRNA extraction. NGF-beta mRNA was determined by a reverse transcriptase-polymerase chain reaction (RT-PCR). NGF-beta and TrkA expression was evaluated by immunofluorescence and flow cytometry analysis.

RESULTS

NGF-beta-specific mRNA was detected in normal and osteoarthritic chondrocytes. NGF-beta protein levels were low in normal chondrocytes, increased in MIN osteoarthritic cartilage and further enhanced in MAX osteoarthritic cartilage. Likewise, TrkA was scarcely expressed on normal chondrocytes and progressively increased on osteoarthritic chondrocytes based on the extent of anatomic damage.

CONCLUSIONS

This is the first study showing that human chondrocytes synthesize NFG-beta and express on their surface the high affinity NGFR (p140 TrkA). Of note, NGF-beta and TrkA were upregulated in osteoarthritic chondrocytes suggesting a role of NGF in the pathophysiology of OA. We can speculate that NGF, like other growth factors, stimulates chondrocyte metabolism in the osteoarthritic process.

[Phenotyping of chondrocytes from human osteoarthritic cartilage: chondrocyte expression of beta integrins and correlation with anatomic injury]

Chondrocyte-ECM (extracellular matrix) interactions are believed to play a pivotal role in the development and metabolic homeostasis of articular cartilage. Cell surface adhesion molecules have been reported to modulate chondrocyte binding to ECM (collagen, fibronectin, laminin) and they also act as transducers of critical signals in many biological processes such as growth, differentiation, migration and matrix synthesis. Recently, it has been shown that normal human articular chondrocytes strongly express beta1 integrins, which are constituted by a common chain (beta1) and a variable alphachain, but the behaviour of these molecules in human osteoarthritic cartilage has not been extensively investigated. We studied the expression of beta integrins (beta1-5, alpha1-6, av chains), LFA-1, ICAM-1 and CD44, on freshly isolated chondrocytes obtained from 10 osteoarthritic patients undergoing surgical knee replacement. Chondrocytes were isolated by enzymatic digestion from three zones of each articular cartilage with a differing degree of macroscopic and microscopic damage. Integrin expression and cell cycle analysis were carried out by flowcytometry. Chondrocytes from costal cartilages of 5 human foetuses were also studied. Chondrocytes from osteoarthritic cartilage expressed high levels of beta1 integrin and, at different percentages, all the alphachains. The alphachain most frequently expressed was alpha1, foilowed by alpha3, alpha5, alpha2, alphav. Integrin expression decreased from the least to the most damaged zone of articular cartilage and cell cycle analysis showed that proliferating chondrocytes (S phase) were prevalent on the latter zone. beta2, beta3, beta2, beta5, CD44, LFA-1/ICAM-1 complex were very low expressed. Fetal chondrocytes strongly expressed beta1 and beta5 chains. These data provide evidence to show that integrin expression on human chondrocytes changes in osteoarthritis and suggest that perturbations of chondrocyte-ECM signalling occur in the development of the disease. The different pattern of expression of beta1 and beta5 chains on adult and fetal chondrocytes leads to speculate that integrins play a key role in control of cartilage morphogenesis and differentiation.

[Hemodynamic and respiratory changes during hip and knee arthroplasty. An echocardiographic study]

BACKGROUND

The "bone cement implantation syndrome" is a rare but severe complication observed especially during the insertion of cemented prostheses in hip and knee replacement surgery. Several mechanisms are involved: effects of methylmethacrilate, embolism of fat, air and bone marrow, and release of tissue thromboplastin during acetabular and femoral reaming. Aim of this study was to detect embolic events, right heart impairment, hemodynamic and respiratory changes during hip and knee replacement surgery.

METHODS

DESIGN

Prospective study, between February-May 2001.

ENVIRONMENT

Orthopedic Operative room.

PATIENTS

Twenty-one patients who underwent total hip or knee arthroplasty under general anesthesia. Patients were divided in methylmethacrylate cemented prostheses groups (CEM, n=10) and totally uncemented prostheses (NON CEM, n=11).

DATA COLLECTION

Standard anesthesia monitoring and omniplane TEE were performed. TEE probe was positioned in order to obtain "inflow-outflow" views of right heart. Measurements were obtained after anesthesia induction (T1), during femoral realing (T2) at prostheses insertion (T3), and at the end of surgery (T4).

RESULTS

Hemodynamic and respiratory parameters measured in different phases of surgical procedures were not different within groups and between groups. Fourtheen patients had TEE evidence of emboli, and the phenomenon was more evident in CEM group (Z= -347; p<0.001). During prostheses insertion, a slight, not significant increase in right ventricular dimensions was observed in both groups, without any right ventricular wall kinetic abnormality. No difference was observed between groups. No adverse cardiac or cerebrovascular events in intra- and postoperatory period were observed.

CONCLUSIONS

In normal patients total hip or knee arthroplasty is associated with embolic phenomena, without any significant change in systemic and right heart hemodynamics. Insertion of cemented prostheses does not modify hemodynamic profile. It remains to be elucidated if the occurrence of emboli has a critical role in patients with cardiorespiratory disease.

[Baropodometric walking analysis in healthy elderly and in arthritic patients before and after knee prosthesis implantation]

Standing and walking are complex activities which require integral skeletal-muscular and central nervous systems. Body is usually, evenly distributed between both the lower limbs with 40% on the ball of the foot and 60% on the heel, therefore, the body's centre of gravity falls between the feet in correspondence to Chopart's articulation. Some diseases can influence standing and walking including cardiovascular diseases (chronic edema, claudication, cardiopathies etc.) neurosensorial ones (cataract, Menière's disease, Parkinson's disease etc.) and orthopedic ones (kyphosis, scoliosis, hallux valgus, metatarsalgia, osteoarthritis etc.). In this study arthritis was considered the main cause of changes in posture and deambulation. An electric baropodometer with a modular platform 240 cm long and 40 cm wide was used which provided the pressure information for each in three distinct phases: static, dynamic and postural Baropodometric step analysis was performed on ten healthy, elderly subjects and ten elderly subjects with arthritis of the knee. The latter group was evaluated both pre- and post prosthetic knee surgery. The data revealed that the ten healthy subjects with arthritis who, prior to surgery presented unequal weight distribution on the diseased side which was slowly redistributed after surgery.

Interleukin-10 and interleukin-10 receptor in human osteoarthritic and healthy chondrocytes

OBJECTIVE

To evaluate the expression of interleukin-10 (IL-10) and interleukin-10 receptor (IL-10R) on chondrocytes from healthy, osteoarthritic, and foetal cartilage from human subjects.

METHODS

Articular cartilage was obtained from 12 patients with osteoarthritis (OA) undergoing surgical knee replacement. Chondrocytes were isolated from the two zones of cartilage showing macroscopically and histologically the lowest (MIN) and highest (MAX) extent of osteoarthritic damage. Additional specimens of cartilage were obtained from 3 healthy donors and 3 human foetuses. IL-10 mRNA expression was determined by a reverse transcriptase-polymerase chain reaction (RT-PCR). For detection of intracellular IL-10 protein, chondrocytes were permeabilized and then incubated with R-phycoerythrin (PE) conjugated rat anti-human IL-10 mAb. Cell surface IL-10R was detected by incubation with biotinylated recombinant human IL-10; after washing, bound IL-10 was revealed by fluorescein (FITC) conjugated streptavidin. Positive chondrocytes were analysed by flowcytometry.

RESULTS

IL-10 mRNA expression was higher in osteoarthritic than in normal chondrocytes. IL-10 protein intracellular levels were significantly higher in MAX than in MIN osteoarthritic cartilage or in healthy cartilage. Cell surface IL-10R was expressed on osteoarthritic chondrocytes with no difference in the degree of cartilage damage. The highest levels of IL-10 protein and IL-10R were found in foetal cartilage.

CONCLUSION

Human chondrocytes synthesise IL-10 and express on their surface IL-10R. Since IL-10 inhibits IL-1 and TNF-alpha expression, its upregulation in osteoarthritic chondrocytes may counteract the detrimental effects of these catabolic cytokines. However, the functions of IL-10 in cartilage may go beyond those activities established in the immunological setting. The high levels of IL-10 and IL-10R in foetal cartilage, an active growing tissue, suggest that IL-10 may play a role in controlling chondrocyte metabolism under physiological conditions.

The immunoglobulin superantigen-binding site of HIV-1 gp120 activates human basophils

OBJECTIVE

To investigate the mechanism whereby HIV-1 envelope glycoprotein gp120 from four different isolates obtained in three different countries induces proinflammatory mediator release from normal human basophils.

METHODS

Histamine, cysteinyl leukotriene C4 (LTC4) and interleukin 4 (IL-4) release into the supernatant was measured in gp120-stimulated peripheral blood basophils from HIV-1 and HIV-2 negative subjects.

RESULTS

The HIV glycoprotein was a potent stimulus for release of these mediators in basophils purified from donors negative for HIV-1 and HIV-2. There was also a correlation (r = 0.58; P < 0.01) between the maximum IL-4 release from basophils induced by gp120 and by anti-IgE. Basophils from which IgE had been dissociated by brief exposure to lactic acid no longer released histamine in response to gp120 and anti-IgE. Anti-IgE specifically desensitized basophils to a subsequent challenge with anti-IgE and gp120. Human monoclonal IgM carrying the VH3 domain, but not that carrying the VH6 domain, inhibited gp120-induced secretion of histamine from basophils in a concentration-dependent manner. Synthetic peptides identical to regions distant from the N- and C-termini of gp120MN inhibited its activating capacity.

CONCLUSIONS

gp120 acts as a viral superantigen interacting with the VH3 domain of IgE to induce the release of preformed and de novo synthesized mediators from human cells carrying the Fc fragment Fc epsilonRI receptor.

Hydroxyapatite coated with heaptocyte growth factor (HGF) stimulates human osteoblasts in vitro

We have studied in vitro the effect of a hydroxyapatite (HA) tricalcium phosphate material coated with hepatocyte growth factor (HA-HGF) on cell growth, collagen synthesis and secretion of metalloproteinases (MMPs) by human osteoblasts. Cell proliferation was stimulated when osteoblasts were incubated with untreated HA and was further increased after exposure to HA-HGF. The uptake of [3H]-proline was increased after treatment with HA. When osteoblasts were exposed to HA-HGF, collagen synthesis was increased with respect to HA. The secretion of MMPs in control cells was undetectable, but in HA and HA-HGF cells MMP 2 and MMP 9 were clearly synthesised. Our results suggest that HA can promote osteoblast activity and that HGF can further increase its bioactivity.

Histamine plasma levels and elimination diet in chronic idiopathic urticaria

OBJECTIVE

The aim of this study was to evaluate the effects of an oligoantigenic and histamine-free diet on patients affected with chronic idiopathic urticaria (CIU).

DESIGN

Ten patients with chronic idiopathic urticaria were prescribed an oligoantigenic and histamine-free diet for 21 days, followed by serial and controlled reintroduction of foods during a further 70 days. Modification in clinical illness as well as histamine plasma levels, post-heparin plasma diamine oxidase (DAO) and intestinal permeability were evaluated.

RESULTS

The oligoantigenic and histamine-free diet induced a significant improvement of symptoms (P<0.05). Moreover, CIU patients on free diet showed higher histamine plasma levels (P<0. 05 vs post-diet and vs controls) that fell to control levels during the oligoantigenic and histamine-free diet. Post-heparin plasma diamine oxidase values were slightly reduced and were unchanged during the diet as well as intestinal permeability, which was always normal in all patients.

CONCLUSIONS

These data suggest that histamine plays a major role in chronic idiopathic urticaria. The finding of normal intestinal permeability suggests that a morphological damage of intestinal mucosa should be excluded in these patients. However, the presence of low levels of post-heparin plasma diamine oxidase may indicate a subclinical impairment of small bowel enterocyte function that could induce a higher sensitivity to histamine-rich or histamine-producing food. European Journal of Clinical Nutrition (2000) 54, 155-158

HIV-1 gp120 induces IL-4 and IL-13 release from human Fc epsilon RI+ cells through interaction with the VH3 region of IgE

HIV-1 glycoprotein (gp) 120 from different clades is a potent stimulus for IL-4 and IL-13 release from basophils purified from healthy individuals seronegative for Abs to HIV-1 and HIV-2. IL-4 mRNA, constitutively present in basophils, was increased after stimulation by gp120 and was inhibited cyclosporin A and tacrolimus. IL-4 and IL-13 secretion from basophils activated by gp120 was not correlated. There was a correlation between the maximum gp120- and anti-IgE-induced IL-4 release from basophils. The average t1/2 gp120-induced IL-4 release was lower than for IL-13 release. Basophils from which IgE had been dissociated by brief exposure to lactic acid no longer released IL-4 in response to gp120 or to anti-IgE. The response to a mAb cross-linking the alpha-chain of high-affinity receptor for IgE (Fc epsilon RI) was unaffected by this treatment. Three human VH3+ monoclonal IgM inhibited gp120-induced secretion of IL-4 from basophils. In contrast, VH6+ monoclonal IgM did not inhibit the release of IL-4 induced by gp120. Synthetic peptides distant from the NH2 and COOH termini of gp120MN inhibited the activating property of gp120MN. These results indicate that gp120, which acts as a viral superantigen, interacts with the VH3 region of IgE to induce the release of IL-4 and IL-13 from human Fc epsilon RI+ cells.

Endogenous superallergen protein Fv interacts with the VH3 region of IgE to induce cytokine secretion from human basophils

BACKGROUND

Protein Fv is an endogenous protein, synthesized in liver and largely released in the digestive tract during acute and chronic viral hepatitis, that binds to immunoglobulin (Ig) from various mammalian and nonmammalian species.

METHODS

Basophils obtained from normal subjects were purified by a double Percoll gradient and elutriation. The secretion of histamine induced by protein Fv was assayed by a fluorometric technique, the extracellular protein levels of IL-4 and IL-13 were measured by ELISA, and IL-4 mRNA levels were evaluated by RT-PCR.

RESULTS

Protein Fv concentration-dependently induced histamine and IL-4 and IL-13 release from purified basophils. IL-4 mRNA, constitutively present in basophils, was increased after stimulation by protein Fv. Histamine and IL-4 secretion from basophils, but not histamine and IL-13 release, activated by protein Fv was significantly correlated (rs = 0.70, p<0.001). Basophils from which IgE had been dissociated by brief exposure to lactic acid no longer released IL-4 in response to protein Fv and anti-IgE. Two preparations of human VH3(+) monoclonal IgM inhibited protein Fv-induced secretion of IL-4 and histamine from basophils. In contrast, VH6(+) monoclonal IgM did not inhibit the release of mediators caused by protein Fv.

CONCLUSIONS

These results indicate that protein Fv, which acts as an endogenous superallergen, interacts with the VH3 domain of IgE to induce the synthesis and release of IL-4, IL-13 and the secretion of histamine from basophils.

Endogenous superallergen protein Fv induces IL-4 secretion from human Fc epsilon RI+ cells through interaction with the VH3 region of IgE

We investigated the mechanism whereby protein Fv (pFv), a human sialoprotein found in normal liver and largely released in the intestinal tract in patients with viral hepatitis, induces mediator release from basophils and mast cells and evaluated whether it also induces IL-4 synthesis and secretion in basophils. pFv is a potent stimulus for histamine and IL-4 release from purified basophils. Histamine and IL-4 secretion from basophils activated by pFv was significantly correlated (rs = 0.70; p < 0.001). There was also a correlation (rs = 0.58; p < 0.01) between the maximum pFv- and anti-IgE-induced IL-4 release from basophils. The average t1/2 for pFv-induced histamine release was lower (3.5+/-1.5 min) than for IL-4 release (79.5+/-8.5 min; p < 0.01). IL-4 mRNA, constitutively present in basophils, was increased after stimulation by pFv and was inhibited by cyclosporin A and tacrolimus. Basophils from which IgE had been dissociated by brief exposure to lactic acid no longer released IL-4 in response to pFv and anti-IgE. The response to an mAb cross-linking the alpha-chain of Fc epsilon RI was unaffected by this treatment. Three human VH3+ monoclonal IgM concentration-dependently inhibited pFv-induced secretion of IL-4 and histamine from basophils and of histamine from human lung mast cells. In contrast, VH6+ monoclonal IgM did not inhibit the release of IL-4 and histamine induced by pFv. These results indicate that pFv, which acts as an endogenous superallergen, interacts with the VH3 domain of IgE to induce the synthesis and release of IL-4 from human Fc epsilon RI+ cells.

Alendronate reduces adhesion of human osteoclast-like cells to bone and bone protein-coated surfaces

Bisphosphonates (BPs) are potent inhibitors of bone resorption and are therapeutically effective in disease of increased bone turnover, but their mechanism(s) of action remain to be elucidated. Using as experimental model human osteoclast-like cell lines derived from giant cell tumors of bone, extensively characterized for their osteoclast features, we investigated the adhesive properties of osteoclasts on bone slices and on different proteins of the extracellular matrix in the presence of BPs. Adhesion assays using bone slices pretreated with ALN, at the established active concentration, showed that, although the morphology of osteoclasts plated onto pretreated bone slices was not modified, the number of adherent cells was reduced by the treatment of about 50% vs. controls. The effect of ALN on the adhesion of osteoclast-like cells onto specific extracellular matrix proteins, such as bone sialoprotein-derived peptide, containing the RGD sequence, conjugated to BSA (BSP-BSA) and fibronectin (FN), was also tested. In the case of FN the treatment with ALN of protein-coated wells did not modify the percentage of cell adhesion compared with the control, whereas onto BSP-BSA the presence of ALN significantly reduced adhesion of about 40-45%, suggesting that the inhibitory effect of ALN on cell adhesion could probably be due to the interference with receptors specifically recognizing bone matrix proteins as alphaVbeta3 integrins. Furthermore, ALN induced Ca-mediated intracellular signals in osteoclasts, triggering a 2-fold increase in intracellular calcium concentration.

Chondrocyte phenotyping in human osteoarthritis

Cell-ECM (extracellular matrix) interactions are believed to play a key role in maintaining the normal structure of tissues such as cartilage. Cell surface adhesion molecules have been reported to mediate chondrocyte binding to ECM proteins in human normal cartilage but the behaviour of these molecules in human osteoarthritic cartilage is unknown. We studied receptor matrix proteins on freshly isolated chondrocytes obtained from 10 patients with osteoarthritis (OA). Chondrocytes were isolated by enzymatic digestion from three zones of the articular cartilage with a different degree of macroscopic and microscopic damage and chondrocyte phenotype was defined by flow cytometry. Chondrocytes strongly expressed beta1, integrin but not beta3 integrin. LFA-1 (CD18/CD11a) and ICAM-1 (CD54) antigens were almost undetectable. Interestingly, beta1 expression was significantly higher in the minimally damaged zone than in the zones with medium and maximum damage. These data show that beta1-integrin-mediated chondrocyte-ECM interactions decrease in osteoarthritic cartilage suggesting that perturbations of chondrocyte-matrix signalling occurs during OA.

Stem cell factor in mast cells and increased mast cell density in idiopathic and ischemic cardiomyopathy

BACKGROUND

We compared cardiac mast cell (HHMC) density and the immunological and nonimmunological release of mediators from mast cells isolated from heart tissue of patients with idiopathic dilated (DCM) (n=24) and ischemic cardiomyopathy (ICM) (n = 10) undergoing heart transplantation and from control subjects (n = 10) without cardiovascular disease.

METHODS AND RESULTS

HHMC density in DCM (18.4+/-1.6 cells/mm2) and ICM (18.4+/-1.5 cells/mm2) was higher than that in control hearts (5.3+/-0.7 cells/mm2; P<.01). The histamine and tryptase contents of DCM and ICM hearts were higher than those of control hearts. The histamine content of the hearts was correlated with mast cell density (r(s)=.91; P<.001). Protein A/gold staining of heart tissue revealed stem cell factor (SCF), the principal growth, differentiating, and activating factor of human mast cells, in HHMC secretory granules. Histamine release from cardiac mast cells caused by immunological (anti-IgE and rhSCF) and nonimmunological stimuli (Ca2+ ionophore A23187) was higher in patients with DCM and ICM compared with control subjects. Immunological activation of HHMC induced a significantly greater release of tryptase and LTC4 in patients with DCM and ICM compared with control subjects.

CONCLUSIONS

Histamine and tryptase content and mast cell density are higher in failing hearts than in control hearts. SCF, present in secretory granules of HHMC, might represent an autocrine factor sustaining mast cell hyperplasia in heart tissue in these patients. The increased local release of fibrogenic factors (eg, histamine, tryptase, and leukotriene C4) might contribute to collagen accumulation in the hearts of patients with cardiomyopathy.

Molecular and cellular biology of mast cells and basophils

In all mammalian species investigated so far, mast cells and basophils are the only cells that synthesize histamine and express plasma membrane receptors that bind IgE with high affinity (Fc epsilonRI). Human basophils and mast cells derive from distinct precursors that originate in the bone marrow and fetal liver and probably circulate in peripheral blood. There is extensive evidence that mast cells and basophils and their mediators are primary effectors of allergic inflammation. Immunologically activated human basophils release two cytokines: IL-4 and IL-13. Expression of several cytokines has been documented in a number of experimental models of human and rodent mast cells. However, to date few studies have analyzed the mechanisms of gene expression in human Fc epsilonRI+ cells. Some of these studies imply a role for NFAT and GATA family members in the IgE-mediated activation of cytokine gene transcription in basophils and mast cells. Studies of human basophils and mast cells isolated from different anatomic sites have established the different profiles of eicosanoids released by these cells. Recently, the characterization of arachidonic acid pools and the identification of novel enzymes involved in arachidonate remodeling and mobilization clarified in part how eicosanoid productions is regulated in mast cells and basophils. In addition to histamine, human mast cell secretory granules contain the neutral proteases tryptase, chymase and carboxypeptidase that possess several biochemical properties. In particular, tryptase may play a role as a fibrogenic factor and chymase might convert angiotensin I to angiotensin II. Mast cells are present in human heart and in human coronary arteries raising the possibility that local activation of cardiac mast cells might contribute to certain cardiovascular diseases. Recent evidence also suggests that mast cells and basophils can play a role during viral and bacterial infections. It is now evident that in man these two cells not only participate in inflammation associated with allergic disease, but also in chronic and fibrotic disorders affecting several organs and in host defense against bacterial and viral infections.

Heterogeneous effects of protamine on human mast cells and basophils

To investigate the mechanisms of anaphylactoid reactions to protamine, we have examined the in vitro effects of increasing concentrations of protamine (10(-6)-3 x 10(-4) mol litre-1) on the release of preformed (histamine and tryptase) and de novo synthesized (peptide leukotriene C4 (LTC4) or prostaglandin D2 (PGD2)) mediators from human basophils and mast cells isolated from lung parenchyma, heart, skin and synovial tissues. Protamine 10(-6)-3 x 10(-4) mol litre-1 induced release of histamine, but not de novo synthesis of LTC4 from basophils. At concentrations from 10(-5) to 3 x 10(-4) mol litre-1 it induced histamine release from human heart (mean 6.5 (SEM 1.5)%), skin (17.7 (4.1)%) and to a lesser extent from synovial mast cells, but not from lung mast cells. Protamine also caused the release of tryptase from heart mast cells (12.8 (3.2) micrograms/10(7) cells), but did not induce de novo synthesis of LTC4 and PGD2 from lung and skin mast cells. In these experiments cross-linking of IgE by anti-IgE caused release of LTC4 or PGD2 from human basophils or mast cells. These results demonstrate that protamine acted as an incomplete secretagogue, causing the release of preformed mediators from human basophils and mast cells.

Eosinophil granule proteins are selective activators of human heart mast cells

Eosinophilia in humans is associated with eosinophil infiltration and cardiac localization of eosinophil granule proteins. Eosinophil cationic proteins are responsible for cardiac disease in some patients with eosinophilia. We have investigated the in vitro effect of four eosinophil granule proteins: eosinophil cationic protein (ECP), major basic protein (MBP), eosinophil-derived neurotoxin (EDN) and eosinophil peroxidase (EPO), on mast cells isolated from human cardiac tissue (HHMC). ECP and, to a lesser extent MBP (0.3-3 microM), but not EDN and EPO, stimulated the release of histamine and tryptase from HHMC. This release reaction induced by ECP and MBP was Ca(2+)- and temperature-dependent and was abolished by preincubation with anti-ECP and anti-MBP, respectively. The activation of HHMC by ECP and MBP was abolished by preincubation with 2-deoxy-D-glucose and antimycin A. These data demonstrate that some eosinophil cationic proteins, ECP and MBP, are selective activators of HHMC, thus contributing to the cardiac lesions in patients with eosinophilia.

Loratadine and desethoxylcarbonyl-loratadine inhibit the immunological release of mediators from human Fc epsilon RI+ cells

BACKGROUND

Loratadine, a novel histamine H1-receptor antagonist, is effective in the treatment of patients with seasonal and perennial rhinitis and some allergic skin disorders. Histamine and other chemical mediators are synthesized and immunologically released by human peripheral blood basophils and tissue mast cells (Fc epsilon RI+ cells).

OBJECTIVE

To evaluate the effects of loratadine and its main metabolite, desethoxylcarbonyl-loratadine (des-loratadine), on the immunological release of preformed (histamine and tryptase) and de novo synthesized mediators (leukotriene C4: LTC4 and prostaglandin D2:PGD2) from human Fc epsilon RI+ cells.

METHODS

Human Fc epsilon RI+ cells purified from peripheral blood and from skin (HSMC) and lung tissue (HLMC) were preincubated with loratadine and des-loratadine before immunological challenge with Der p 1 antigen or anti-Fc epsilon RI. The release of preformed mediators (histamine and tryptase) and de novo synthesized eicosanoids was evaluated in the supernatants of human Fc epsilon RI+ cells.

RESULTS

Preincubation (15 min, 37 degrees C) of purified (36-74%) basophils with loratadine (3 x 10(-6)-10(-4)M) and des-loratadine before Der p 1 antigen or anti-Fc epsilon RI challenge concentration-dependently (5-40%) inhibited the release of histamine and LTC4. Loratadine (3 x 10(-6)-10(-4)M) and des-loratadine also inhibited (10-40%) histamine, LTC4, and PGD2 release from purified HLMC (16-68%) activated by anti-Fc epsilon RI. Loratadine (3 x 10(-6)-10(-4)M) and des-loratadine caused concentration-dependent inhibition (10-40%) of histamine, tryptase, LTC4, and PGD2 release from purified HSMC (24-72%) immunologically challenged with anti-Fc epsilon RI.

CONCLUSION

These results indicate that loratadine and its main metabolite have anti-inflammatory activity by inhibiting the release of preformed and de novo synthesized mediators from human Fc epsilon RI+ cells.

Integrin expression on chondrocytes: correlations with the degree of cartilage damage in human osteoarthritis

OBJECTIVE

To verify the distribution of different types of beta 1 integrin on the plasma membrane of chondrocytes and to correlate the pattern of integrin expression to the severity of osteoarthritis (OA).

METHODS

The articular cartilage of ten OA patients who had undergone surgical knee replacement for "genu varum" were studied. The cartilage was separated into three zones that macroscopically and microscopically showed a decreasing degree of anatomic lesions. After enzymatic digestion, the isolated chondrocytes were immediately challenged with monoclonal antibodies against the beta 1, alpha 1-6 and alpha v chains. The phenotypic study was paralleled by a cell cycle analysis performed by flow cytometry on chondrocytes stained with propidium iodide.

RESULTS

Chondrocytes isolated from the articular cartilage of osteoarthritic patients expressed, in different percentages, all the alpha chains (alpha 1-6 and alpha v) of the beta 1 integrins. The alpha chain most frequently expressed was alpha 1, followed by alpha 3, alpha 5, alpha 2 and alpha v, with lesser amounts of alpha 4 and alpha 6. The beta 1 chain was expressed (on average) on the 40% of the chondrocytes regardless of the zone they were isolated from. Differential phenotypic analysis of the three zones showed that beta 1 integrins correlate inversely with the severity of the anatomic lesions and the cycle phase of the chondrocytes (the G0/G1 phase prevailed in the anatomically normal cartilage of the least damaged zone, and the S-phase in the most damaged zone).

CONCLUSIONS

This study provides evidence of the existence of beta 1 integrins on the surface of chondrocytes from human OA cartilage, all of the alpha chains being represented, although in different percentages. Moreover, an inverse correlation was demonstrated between the severity of the anatomical changes found in the zones and the phenotypic/metabolic changes of the cells. These results, together with the well known inside-out signaling function of the adhesion molecules, highlight the key role of matrix interactions in the pathogenesis of the anatomic changes in OA.

Oxatomide inhibits the release of proinflammatory mediators from human basophils and mast cells

Oxatomide (OXA), a histamine H1 receptor antagonist, is effective in the treatment of patients with allergic rhinitis, some allergic skin disorders, and bronchial asthma. We have characterized the effect of OXA on the immunologic release of preformed (histamine and tryptase) and de novo synthesized mediators (leukotriene C4:LTC4 and prostaglandin D2:PGD2) from human basophils and mast cells purified (from 10 to 82%) from human lung parenchyma (HLMC) and skin tissue (HSMC). Preincubation (15 min, 37 degrees C) of basophils with OXA (10(-7)-10(-5) M) before Der p I antigen or anti-IgE challenge concentration-dependently (10-40%) inhibited the immunologic release of histamine and LTC4. OXA (10(-7)-10(-5) M) also inhibited (10-40%) histamine, tryptase and LTC4 release from HLMC activated by anti-IgE. In addition, OXA caused a concentration-dependent inhibition of histamine, tryptase and PGD2 release from HSMC immunologically challenged with a monoclonal antibody against the alpha chain of the high affinity receptor for IgE (anti-Fc epsilon RI) or anti-IgE. These results demonstrate that OXA exerts anti-inflammatory activities by inhibiting the release of preformed and de novo synthesized mediators from human basophils and mast cells.

Contrast media are incomplete secretagogues acting on human basophils and mast cells isolated from heart and lung, but not skin tissue

To investigate the mechanisms of anaphylactoid reactions to radiocontrast media, in vitro mediator release induced by three iodinated contrast agents was examined using peripheral blood basophils and mast cells purified from human lung parenchyma, heart, and skin tissues. Three iodinated contrast agents, sodium and meglumine salts of ioxaglic acid, sodium and meglumine salts of ioxithalamic acid, and ioversol, were incubated with basophils purified from peripheral blood and human mast cells isolated and purified from different anatomical sites. Release of preformed (histamine and tryptase) and de novo synthesized mediators (prostaglandin D2 and leukotriene C4) into the supernatans was determined at various contrast medium concentrations after incubation for 60 min. Ioxaglate (0.2-0.3 M), ioxithalamate (0.3-0.5 M), and to a lesser extent ioversol (0.3-0.5 M) induced histamine release from basophils in a concentration-dependent manner. All three induced the release of preformed mediators (histamine and tryptase) from human lung, but not from skin mast cells. They also induced histamine and tryptase release from human heart mast cells. However, they did not induce the de novo synthesis of leukotriene C1 or prostaglandin D2 from human basophils or any type of mast cell examined. Cross-linking of IgE by anti-IgE induced the release of leukotriene C4 or prostaglandin D2 from human basophils or mast cells. Mannitol, an osmotic stimulus, induced the release of histamine from human basophils, but to a lesser extent from mast cells. These results show that different contrast media can differ in their ability to release mediators from enriched preparations of human basophils and mast cells. The three contrast agents examined act on basophils and mast cells as incomplete secretagogues, causing the release of preformed mediators, but not these novo synthesis of chemical mediators. It may be useful to measure plasma tryptase levels to detect adverse reactions caused by iodinated radiographic contrast materials.

Eosinophil granule proteins activate human heart mast cells

Eosinophilia in humans is often associated with heart disease and cardiac localization of eosinophil granule proteins, and several results suggest that granule proteins mediate endomyocardial damage. Here we investigated the in vitro effects of the four principal eosinophil granule proteins (eosinophil cationic protein (ECP), major basic protein (MBP), eosinophil-derived neurotoxin, and eosinophil peroxidase (EPO)) on the activation of effector cells of inflammation (mast cells) isolated from human heart tissue (HHMC). ECP and, to a lesser extent, MBP (0.3-3 microM), but not eosinophil-derived neurotoxin and eosinophil peroxidase stimulated the release of preformed (histamine and tryptase) and the de novo synthesis of vasoactive and proinflammatory mediators (PGD2) from HHMC. Activation of HHMC by ECP and MBP was Ca2+- and temperature-dependent and was abolished by preincubation (15 min, 37 degrees C) with 2-deoxy-D-glucose (10 mM) and antimycin A (1 microM). There was a significant correlation between the maximal percentage of histamine release induced by ECP and anti-IgE from HHMC (rs = 0.73; p &lt; 0.005), by MBP and anti-IgE (rs = 0.79; p &lt; 0.001), and by ECP and MBP (rs = 0.65; p &lt; 0.005). A positive correlation was also found between histamine and tryptase secretion (rs = 0.71; p &lt; 0.001) and between histamine and PGD2 release induced by ECP from HHMC (rs = 0.85; p &lt; 0.001). This is the first demonstration that some eosinophil cationic proteins, namely ECP and MBP, found at the site of heart damage in patients with eosinophilia, act as complete secretagogues on HHMC. This observation indicates another mechanism by which infiltrating eosinophils and their metabolic products cause inflammatory reactions and thus endomyocardial lesions in patients with eosinophilia.