Cytokine-induced killer cells: A novel treatment for allergic airway inflammation

Expression of constitutively active TβRI leads to attenuation of ovalbumin-induced allergic airway inflammation associated with augmented M2 polarization of alveolar macrophage

BACKGROUND

Transforming growth factor-β (Tgf-β) plays an important role in the pathogenesis of asthma through the regulation of T cells and airway epithelium. Its functions in alveolar macrophage (AM) during allergic airway inflammation remain unknown.

METHODS

A murine asthma model was induced with ovalbumin (ova) in TβRICA/Fsp1-Cre transgenic mice expressing constitutively active Tgf-β receptor type I (TβRICA) under the control of Fsp1-Cre transgene. Cells in the bronchoalveolar lavage (BAL) were collected to study immune cell infiltration in the lungs. Cytokine levels in BAL fluid were measured by enzyme-linked immunoassay (ELISA). Lungs were sectioned and stained with hematoxylin and eosin, periodic acid-Schiff, and trichrome for histopathologic evaluation. AMs were assessed by flow cytometry and were sorted for quantitative polymerase chain reaction analysis.

RESULTS

Our data indicated that TβRICA transcripts were induced in AMs of TβRICA/Fsp1-Cre mice. Following the ova challenges, TβRICA/Fsp1-Cre mice exhibited reduced cellular infiltration of the airway, reduced pulmonary fibrosis, and reduced bronchial mucus secretion as compared to ova-challenged wild-type mice. An alternatively activated macrophage (M2) polarization was significantly elevated in the lungs of ova-challenged TβRICA/Fsp1-Cre mice as reflected by increased numbers of AMs expressing M2 subtype marker, CD163, in the lungs and enhanced expression of CCR2 and CD206 in AMs. Moreover, TβRICA/Fsp1-Cre AMs showed augmented expression of transcription factors, Foxo1, and IRF4, which are known to be positive regulators for M2 polarization.

CONCLUSIONS

Expression of TβRICA in AMs promoted M2 polarization and ameliorated allergic airway inflammation in an ova-induced asthma mouse model.

The role of monocytes and natural killers' immunophenotypic subsets in bronchial asthma in children

Objective: Childhood bronchial asthma (BA) is a globally significant chronic disease with major health consequences. Recently, focus on the role of the innate immune system has been highlighted. Therefore, this study explores the role of circulating monocytes and natural killer (NK) clusters in childhood asthma.Methods: This case-control study enrolled 50 children with asthma divided equally into severe and mild groups and 26 healthy children. Flow-cytometry analysis was used to identify circulating blood monocytes and natural killers' subsets. In addition, pulmonary function test (spirometry) for children with asthma was performed.Results: This study showed significant negative correlations between frequency of total circulating, classical, intermediate, and nonclassical monocytes with ratio of forced expiratory volume/forced vital capacity (FEV1/FVC) (r = -0.637, P < 0.001; r = -0.575, P < 0.001; r = -0.657, P < 0.001; r = -0.329, P = 0.004, respectively). Also, there was significant negative correlations between frequency of total NKs and CD56^dim CD16+ NK with FEV1/FVC (r = -0.584, P < 0.001) and (r = -0.579, P < 0.001). Significant predictors of childhood asthma severity were frequencies of total monocytes, total NKs, intermediate monocytes, and CD56^dimCD16+ NK.Conclusion: Finally, we concluded that the FEV1/FVC is linked to aberrations of monocytes' and natural killers' immunophenotypic subsets in children with asthma. The frequencies of total monocytes and NK are significant predictors of severity of childhood asthma. The frequencies of CD14^high CD16+ intermediate monocytes and CD56^dim CD16+ NK cells are the best independent predictors of severity in children with asthma.

Inflammation in Asthma Pathogenesis: Role of T cells, Macrophages, Epithelial Cells and Type 2 Inflammation

Asthma is a chronic disease with abnormal inflammatory and immunological responses. The disease initiated by antigens in subjects with genetic susceptibility. However, environmental factors play a role in the initiation and exacerbation of asthma attack. Asthma is T helper 2 (Th2)-cell-mediated disease. Recent studies indicated that asthma is not a single disease entity, but it is with multiple phenotypes and endotypes. The pathophysiological changes in asthma included a series of subsequent continuous vicious circle of cellular activation contributed to induction of chemokines and cytokines that potentiate inflammation. The heterogeneity of asthma influenced the treatment response. The asthma pathogenesis driven by varied set of cells such as eosinophils, basophils, neutrophils, mast cells, macrophages, epithelial cells and T cells. In this review the role of T cells, macrophage, and epithelial cells are discussed.

The Role of T Cells and Macrophages in Asthma Pathogenesis: A New Perspective on Mutual Crosstalk

Asthma is associated with innate and adaptive immunity mediated by immune cells. T cell or macrophage dysfunction plays a particularly significant role in asthma pathogenesis. Furthermore, crosstalk between them continuously transmits proinflammatory or anti-inflammatory signals, causing the immune cell activation or repression in the immune response. Consequently, the imbalanced immune microenvironment is the major cause of the exacerbation of asthma. Here, we discuss the role of T cells, macrophages, and their interactions in asthma pathogenesis.

Insights into endotoxin-mediated lung inflammation and future treatment strategies

INTRODUCTION

Airway inflammatory disorders are prevalent diseases in need of better management and new therapeutics. Immunotherapies offer a solution to the problem of corticosteroid resistance. Areas covered: The current review focuses on lipopolysaccharide (Gram-negative bacterial endotoxin)-mediated inflammation in the lung and the animal models used to study related diseases. Endotoxin-induced lung pathology is usually initiated by antigen presenting cells (APC). We will discuss different subsets of APC including lung dendritic cells and macrophages, and their role in responding to endotoxin and environmental challenges. Expert commentary: The pharmacotherapeutic considerations to combat airway inflammation should cost-effectively improve quality of life with sustainable and safe strategies. Selectively targeting APCs in the lung offer the potential for a promising new strategy for the better management and treatment of inflammatory lung disease.