Allergen activates peripheral blood eosinophil nuclear factor-κB to generate granulocyte macrophage-colony stimulating factor, tumour necrosis factor-α and interleukin-8

BACKGROUND: Allergic inflammation is characterized by the influx and activation of eosinophils. Cytokines generated by both resident and infiltrating cells are responsible for the initiation and maintenance of this pathogenesis. This study focuses on allergen-induced activation of eosinophil NF-kappaB and generation of granulocyte macrophage-colony stimulating factor (GM-CSF), TNF-alpha, and IL-8. METHODS: Peripheral blood eosinophils were enriched to >99.9% by Percoll gradient sedimentation and negative magnetic affinity chromatography. NF-kappaB activation by 10 microg/mL house dust mite (HDM) extract was demonstrated immunocytochemically using a monoclonal antibody against the active form of NF-kappaB (NF-kappaBa). The authenticity of NF-kappaB was confirmed by Western blot. Cytokine production was assessed both by immuno-staining of eosinophils and by assay of cytokines in the cell supernatant. RESULTS: Activation of peripheral blood eosinophils from atopic, but not non-atopic, donors induced activation of NF-kappaB, which peaked at 4 h and was accompanied by a decline in IkappaB-alpha. The activation of authentic NF-kappaB was confirmed in gel shift assays. Supershift assays showed p65 to be the major subunit of eosinophil NF-kappaB. Immunofluorescent confocal microscopy demonstrated localization of NF-kappaBa to the nucleus. Following activation, cytokine immunoreactivity was seen in a fraction of the eosinophils and cytokines were released into the supernatant. The NF-kappaB inhibitors, calpain inhibitor 1 (10 microm), pentoxifylline (0.5 mm), pyrrolidine dithiocarbamate (PDTC, 10 microm) or gliotoxin (1 pg/mL) reduced the generation of GM-CSF, TNF-alpha and IL-8 in parallel with their inhibition of NF-kappaB. CONCLUSIONS: HDM allergen activates human eosinophil NF-kappaB leading to the production of the cytokines GM-CSF, TNF-alpha and IL-8. We speculate that a role for eosinophil NF-kappaB-dependent cytokines is to act as an autocrine loop augmenting the survival of eosinophils in vivo.     

Polymorphism of the mast cell chymase gene (CMA1) promoter region: lack of association with asthma but association with serum total immunoglobulin E levels in adult atopic dermatitis

BACKGROUND: Mast cell chymase has the potential to be an important mediator of inflammation and remodelling in the asthmatic lung. Previous studies have examined association between promoter polymorphism of the chymase gene (CMA1) and allergic phenotypes but the significance of this polymorphism is unclear. We have examined association of a CMA1 variant in relation to asthma in a large UK Caucasian family cohort. METHODS: A polymorphism of the CMA1 gene promoter (-1903G/A) was genotyped in 341 asthmatic families and in 184 non-asthmatic adults recruited from the UK PCR-RFLP based genotyping. Association with asthma diagnosis, atopy, specific and total IgE, and atopy and asthma severity was examined. RESULTS: Case-control studies did not reveal a significant difference in allele frequency between asthmatics and controls. A significant association was found between CMA1 genotypes and total IgE levels in subjects with self-reported eczema that remained significant after correction for multiple testing (median total serum IgE GG 297 kU/L, GA 144 kU/L, AA 48.4 kU/L, Pc=0.0032). CONCLUSION: These data suggest that CMA1 promoter polymorphism does not contribute to asthma susceptibility or severity but may be involved in regulating IgE levels in patients with eczema.     

Care pathways for acute stroke care and stroke rehabilitation: from theory to evidence.

Care pathways aim to promote evidence- and guideline-based care, improve the organisation and efficiency of care, and reduce cost. In the past decade, care pathways have been increasingly implemented as a tool in acute stroke care and stroke rehabilitation. In the most recent Cochrane systematic review, which included three randomised and 12 non-randomised studies, patient management with stroke care pathways was found to have no significant benefit on functional outcome, and patient satisfaction and quality of life might actually be worse. On the other hand, it was associated with a higher proportion of patients receiving investigations and a lower risk of developing certain complications such as infections and readmissions. Overall, the evidence supports the use of care pathways in acute stroke but not stroke rehabilitation. Future developments, including electronic care pathways, patient pathways, and pre-hospital care pathways for hyperacute stroke, will be discussed.     

Radiologist perceptions of radiographer role development in Scotland

AimTo survey the perceptions of the Scottish radiology community in relation to radiographer role development.MethodsA postal questionnaire was sent to all consultant radiologists recorded on the NHS Scotland database of consultants.ResultsResponse rate was 63%. (i) Respondents considered increased professional standing of radiographers, best use of manpower resources, reduced pressure on the service and improved recruitment and retention, as positive advantages of radiographer development. (ii) The potential impact on radiology specialist registrar training, lack of clear medico-legal responsibilities and radiographers recognising the limitations of their abilities were identified as the main areas of radiologist anxiety. (iii) Fifty-seven percent did not consider current post-registration radiography education and training resources adequate to underpin the requirement of developed roles. (iv) Barriers to radiographer development were identified as lack of radiography and radiology staff, suitable education, financial constraints, traditional views and resistance to change. (v) Eighty-two percent reported support for radiographer role development and willingness to participate actively in developments.ConclusionDespite reservations Scottish radiologists are supportive of the development of radiography colleagues, however, guidance is required on the medico-legal and accountability aspects of radiographers assuming new roles. Radiologist involvement in education and training for new roles may increase their confidence and trust in radiographers to work within the limitations of their competency and training.     

The extent of surface contamination of retailed chickens with Campylobacter jejuni serogroups.

Eighty-two chickens purchased at 11 retailers (supplied by 12 wholesalers) in the south of England were cultured for Campylobacter jejuni by a method involving total immersion. The organism was isolated from 22 (48%) of 46 fresh birds, 12 of 12 uneviscerated (New York dressed) birds, but only 1 of 24 frozen birds. Viable counts of up to 1.5 x 10(6)/chicken were obtained from fresh birds and 2.4 x 10(7)/chicken from uneviscerated birds. Surface swabbing of breasts, thighs, wings and vents of fresh chickens showed that contamination was generally distributed over the carcasses. Salmonellas were found in only 2 of 69 of the fresh chickens. The prevalence of several Lior and Penner C. jejuni serogroups was similar in chickens and sporadic human cases of enteritis. Penner serogroup 4 (mostly of Lior serogroup 1) was found in 26% of human isolates and 14% of chicken isolates. The rising incidence of campylobacter enteritis during the last 6 years could well be a reflection of the increasing proportion of fresh chickens consumed over that period (32% higher in 1986 than in 1981).