Macrophage migration inhibitory factor (MIF) is an immunologic regulator that is expressed in inflammatory and autoimmune disorders. We investigated MIF's role in asthma using genetic approaches in a mouse model and in a cohort of asthma patients. Mice genetically deficient in MIF that were primed and aerosolchallenged with ovalbumin showed less pulmonary inflammation and lower airway hyperresponsiveness than genetically matched, wild-type controls. MIF deficiency also resulted in lower titers of specific IgE, IgG 1, and IgG2a, and decreased pulmonary, TH2 cytokine levels. IL-5 concentrations were lower and corresponded to decreased eosinophil numbers in bronchoalveolar lavage fluid. T cell studies also showed a lower level of antigen-specific responses in MIF-KO versus wild-type mice. In an analysis of 151 white patients with mild, moderate, or severe asthma (Global Initiative for Asthma criteria), a significant association was found between mild asthma and the low-expression, 5-CATT MIF allele. Pharmacologic inhibition of MIF may be beneficial and could be guided by the MIF genotype of affected individuals.cytokine ͉ genetic polymorphism ͉ innate immunity

In severe asthma, poor control could reflect issues of medication adherence or inhaler technique, or that the condition is refractory. This study aimed to determine if an intervention with (bio)feedback on the features of inhaler use would identify refractory asthma and enhance inhaler technique and adherence.Patients with severe uncontrolled asthma were subjected to a stratified-by-site random block design. The intensive education group received repeated training in inhaler use, adherence and disease management. The intervention group received the same intervention, enhanced by (bio)feedback-guided training. The primary outcome was rate of actual inhaler adherence. Secondary outcomes included a pre-defined assessment of clinical outcome. Outcome assessors were blinded to group allocation. Data were analysed on an intention-to-treat and per-protocol basis.The mean rate of adherence during the third month in the (bio)feedback group (n=111) was higher than that in the enhanced education group (intention-to-treat, n=107; 73% 63%; 95% CI 2.8%-17.6%; p=0.02). By the end of the study, asthma was either stable or improved in 54 patients (38%); uncontrolled, but poorly adherent in 52 (35%); and uncontrolled, but adherent in 40 (27%).Repeated feedback significantly improved inhaler adherence. After a programme of adherence and inhaler technique assessment, only 40 patients (27%) were refractory and adherent, and might therefore need add-on therapy.

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SummaryGlucocorticosteroids are a very effective treatment for asthma and other chronic inflammatory diseases . However, a small proportion ofpatients is resistant to the therapeutic effects of glucocorticoids. Pharmacokinetic and ligand binding studies suggest that the molecular abnormality in steroid resistance lies distal to nuclear translocation . We have previously reported that there is a decreased ability of glucocorticoid receptors (GR) to bind to the DNA-binding site in peripheral blood mononuclear cells (PBMC) after dexamethasone treatment . This reduced DNA binding was due to a decrease in the number of receptors available rather than an alteration in affinity for DNA . To study this reduced DNA binding, we examined the ability ofthe nuclear translocated transcription factors activator protein 1 (AP-1), nuclear factor KB (NF-KB) and cyclic AMP response element-binding protein (CREB) to bind to their DNA-binding sites and to interact with GR in PBMC from patients with steroid-sensitive and steroid-resistant asthma. There was a significant reduction in the interaction between GR and AP-1 in these steroidresistant patients, although interaction with other transcription factors activated in inflammation (NF-KB and CREB) was unaffected . An increase in the basal levels ofAP-1 DNA binding was also detected in the nuclei from steroid-resistant asthmatic patients . There were no differences in the amount of messenger RNA detected for the components of AP-1, c-Fos and c-Jun, nor in the sequences of these messenger RNAs. These results suggest either that the ability of the GR to bind to glucocorticoid response elements and AP-1 is altered in steroidresistant patients or that increased levels ofAP-1 prevent GR DNA binding, and that this may be the molecular basis ofresistance to the andinflammatory effect o£ steroids in these cells.