Regulatory T cells in bronchial asthma

Abstract

The main focus of this review was the role of a specific subset of T cells with immunomodulatory or immunosuppressive activities, termed regulatory T cells (Tregs), in the pathogenesis and treatment of bronchial asthma. Evidence that these cells are important in maintaining immune homeostasis in health and exhibit impaired activity in active disease will be discussed. Their therapeutic potential is perhaps best highlighted by evidence that therapies with demonstrated efficacy in allergic and asthmatic disease are associated with the induction or restoration of regulatory T‐cell function, e.g. glucocorticoids, allergen immunotherapy. Strategies to improve the safety and efficacy of these treatments and that induce or boost Tregs in bronchial asthma are discussed.

Peripheral Blood and Tissue T Regulatory Cells in Chronic Rhinosinusitis

“…3,9,10 These cells play roles in the coordination and regulation of recruitment of effector T cells to sites of inflammation and also have the ability to impair the capacity of antigen-presenting cells (APCs) to prime adaptive immune responses. 9,10,12 Decreased numbers and/or impaired function Tregs have previously been implicated in the development of autoimmunity 13,14 and other immune diseases, including asthma and allergy. 9,12,15 Previous studies of populations of Chinese and European origin have indicated a decreased expression of FoxP3 and TGF-␤1 in tissue samples from subjects with CRSwNP compared with CRSsNP or control subjects assessed by a variety of methods.…”

“…9,10,12 Decreased numbers and/or impaired function Tregs have previously been implicated in the development of autoimmunity 13,14 and other immune diseases, including asthma and allergy. 9,12,15 Previous studies of populations of Chinese and European origin have indicated a decreased expression of FoxP3 and TGF-␤1 in tissue samples from subjects with CRSwNP compared with CRSsNP or control subjects assessed by a variety of methods. 3,6,[16][17][18] Other studies investigating T-cell phenotypes in Chinese subjects with or without nasal polyps also confirm down-regulation of FoxP3 mRNA expression and a significantly decreased infiltration of FoxP3 ϩ Tregs into nasal polyp tissue, thereby implicating a role of Tregs in these disorders at the local tissue level.…”

“…12,15 Because, seven and six CRS subjects in both our groups had asthma as a confounding disease, we analyzed the Treg populations in these subjects stratified based on asthma. There were no significant differences in the number of CD25 ϩ -FoxP3 ϩ (Fig.…”

The Contrasting Roles of T Regulatory Cells in Bacterial Lung Diseases

“…Another study suggests that asthmatics have lower overall expression of FoxP3 compared to healthy donors (Lloyd & Hawrylowicz, 2009). Furthermore, glucocorticoid treatment has been shown to transiently increase T reg cell numbers in asthmatic patients (Ryanna et al, 2009). A number of strategies have been proposed to increase T reg cells in asthmatics, including isolation and in vitro expansion of T reg cells, followed by their transfer back into the host (Ryanna et al, 2009).…”

“…Furthermore, glucocorticoid treatment has been shown to transiently increase T reg cell numbers in asthmatic patients (Ryanna et al, 2009). A number of strategies have been proposed to increase T reg cells in asthmatics, including isolation and in vitro expansion of T reg cells, followed by their transfer back into the host (Ryanna et al, 2009). However, this would be an expensive and lengthy process.…”