Th2 cells

A cytokine, secreted by TH2-cells, stimulates B-cells in different stages of their development. It may act as a growth factor or as a differentiation factor, causing B-lymphocytes to switch antibody to IgE. In T-cells it causes differentiation into TH2-cells. 

A cytokine, secreted by TH2-cells and mast cells, stimulates B-cell growth, acts as hematopoietic factor for growth factor eosinophils, and extends the life span of eosinophils. 

Fig. 3. Th2 cells provide cytokines such as IL-4, IL-5, IL-9 and IL-13, which are essential for differentiation, survival and activity of basophils, mast cells and eosinophils. IL-4 and IL-13 induce IgE production from B cells. IL-5 induces eosinophils, increases eosinophil survival and reduces apoptosis. IL-9 stimulates mast cells. 

Fujiwara M, Hirose K, Kagami S. Takatori H. Waka-shin H, Tamachi T, Watanabe N. Saito Y. Iwamoto I. Nakajima H T-bet inhibits both Th2 cell-mediated eosinophil recruitment and Th17 cell-mediated neutrophil recruitment into the airways. J Allergy Chn Immunol 2007 119 662-670. 

Basophils Drive Th2-Cell Differentiation through Secretion ofTh2 Cytokines and Antigen Presentation... 

Ray A, Cohn L (1999) Th2 cells and GATA-3 in asthma new insights into the regulation of airway inflammation. J Clin Invest 104(8) 985-993... 

Mariani M, Lang R, Binda E, Panina-Bordignon P, D Ambrosio D. Dominance of CCL22 over CCL17 in induction of chemokine receptor CCR4 desensitization and internalization on human Th2 cells. Eur J Immunol 2004 34(1) ... 

CCR4 and CCR8 have been described as receptors preferentially expressed on Th2 cells (58,69,72,79,80). Just as for the Thl-associated chemokine receptors, despite the strong preferential association of CCR4 and CCR8 with Th2 cells, there is no evidence that these Th2-associated receptors are necessary for Th2 cell polarization (60,81). 

T helper 2 (Th2) CCR4, CCR8 Th2 cells are a subset of CCR4+ cells... 

Randolph DA, Huang G, Carruthers CJ, Bromley LE, Chaplin DD. The role of CCR7 in TH1 and TH2 cell localization and delivery of B cell help in vivo. Science 1999 286 2159-2162. 

A primary chemokine receptor associated with Th2-type responses is CCR8, which is also upregulated on Th2 cells derived in vitro. CCR8 is expressed by thymocytes, monocytes, as well as Th2 cells, and serves as the receptor for I-309/TCA-3/CCL1. In humans, expression of CCR8 was found on T cells in endobronchial biopsies of asthmatic patients taken 24 hours after allergen... 

Findings from studies of schistosomiasis-induced liver fibrosis, as well as other models of pulmonary, kidney, and liver fibrosis, strongly support the role of CD4+ Th2 cells in the progression of fibrosis (4). In this regard, analyses of gene and protein expression after stimulation by Thl (vs. Th2) cytokines indicates that IL-4 is found at increased concentrations in the bronchoalveolar lavage (BAL) fluid of patients with idiopathic pulmonary fibrosis, as well as in the peripheral blood mononuclear cells of those afflicted with periportal fibrosis (10,53-56). 

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