Role of IgE in Th2 cell-mediated allergic airway inflammation.
Recent studies with gene knockout mice have demonstrated that T helper 2 (Th2) cell-derived cytokines, including IL-4, IL-5, and IL-13, play important roles in causing allergic airway inflammation. In addition to Th2 cytokines, IgE-dependent activation of mast cells has been suggested to play a role in allergic airway inflammation. In this review, we will discuss the role of IgE in Th2 cell-mediated allergic airway inflammation. We used IgE transgenic mice, which enabled us to investigate the role of IgE without the influence of activated T cells and other immunoglobulins. Whereas IgE cross-linking by antigens did not induce eosinophil recruitment into the airways or airway hyperreactivity, IgE cross-linking induced CD4+ T cell recruitment into the airways. In addition, when antigen-specific Th2 cells were transferred to IgE transgenic mice, IgE cross-linking significantly enhanced antigen-induced eosinophil recruitment into the airways. These findings suggest that IgE-dependent mast cell activation plays an important role in allergic airway inflammation by recruiting Th2 cells into the site of allergic inflammation.
Maezawa
Yuko
Y
Department of Internal Medicine II, Chiba University School of Medicine, Chiba, Japan.
Nakajima
Hiroshi
H
Kumano
Kotaro
K
Kubo
Shuichi
S
Karasuyama
Hajime
H
Iwamoto
Itsuo
I
D000818:Animals; D003429:Cross Reactions / Q000276:immunology; D016207:Cytokines / Q000502:physiology; D006801:Humans; D007073:Immunoglobulin E / Q000502:physiology*; D011014:Pneumonia / Q000276:immunology* / Q000503:physiopathology*; D012130:Respiratory Hypersensitivity / Q000276:immunology* / Q000503:physiopathology*; D018418:Th2 Cells / Q000737:chemistry / Q000502:physiology*
D016207:Cytokines; D007073:Immunoglobulin E