Biomarkers in the Management of Difficult Asthma

Abstract

Difficult asthma is a heterogeneous disease of the airways including various types of bronchial inflammation and various degrees of airway remodeling. Therapeutic response of severe asthmatics can be predicted by the use of biomarkers of Type2-high or Type2-low inflammation. Based on sputum cell analysis, four inflammatory phenotypes have been described. As induced sputum is time-consuming and expensive technique, surrogate biomarkers are useful in clinical practice.Eosinophilic phenotype is likely to reflect ongoing adaptive immunity in response to allergen. Several biomarkers of eosinophilic asthma are easily available in clinical practice (blood eosinophils, serum IgE, exhaled nitric oxyde, serum periostin). Neutrophilic asthma is thought to reflect innate immune system activation in response to pollutants or infectious agents while paucigranulocytic asthma is thought to be not inflammatory and characterized by smooth muscle dysfunction. We currently lack of user-friendly biomarkers of neutrophilic asthma and airway remodeling.In this review, we summarize the biomarkers available for the management of difficult asthma.

Serum levels of epithelial‐derived mediators and interleukin‐4/interleukin‐13 signaling after bronchial challenge with Dermatophagoides pteronyssinus in patients with allergic asthma

“…Although the treatment of asthma is moving forward with the onset of the biological therapy era, leading to greater opportunities for individualized treatment, identification of new molecular targets and biomarkers reflecting them is needed. Currently, assessment of airway type 2 inflammation is related with validated biomarkers of eosinophilic airway inflammation, such as blood eosinophil count, sputum eosinophilia, FeNO, serum periostin and IgE . We also checked blood eosinophil count and FeNO, and observed that following the allergen exposure, these biomarkers only exhibited a significant increase in the AA group, without changes in HS.…”

Guiding principles for use of newer biologics and bronchial thermoplasty for patients with severe asthma

“…Although not currently feasible for widespread use, induced sputum is generally considered the gold standard noninvasive method for assessing airway inflammation in asthma to identify inflammatory phenotype and could be valuable in phenotyping patients with asthma. 25 Moreover, sputum analysis allows for assessment of not only eosinophil levels but also other inflammatory cells (particularly neutrophils, which are not available from blood).…”

Evaluation of Interleukin- 5 in Mild and Moderate Asthmatic Patients Following Corticosteroid Therapy

“…The exact functional role of each individual cytokine in the pathogenesis of the disease remains to be fully established. [9,10] The potential role of type 2 T-helper cell-cytokines in asthma is increasingly being recognized in particular interleukin -4, interleukin -5 and interleukin -13. Th2 cells are thought to control the growth and effectors function of those cell types that are involved in allergic inflammatory responses in asthmatic patients.…”

“…From these inflammatory cells the eosinophil is considered a key effectors cell in the pathogenesis of allergic inflammation in asthma. [7][8][9][10] IL-5 seems to be the primary cytokine involved in the production, differentiation, maturation and activation of eosinophils. [13,14] The ant-inflammatory effects of glucocorticoids in asthma include modulation of cytokine and chemokine production, inhibition of eicosanoid synthesis, marked inhibition of accumulation of basophils, eosinophils and other leukocyte in lung tissue and decreased vascular permeability.…”