| First Author | Crosby JR | Year | 2002 |
| Journal | Am J Physiol Lung Cell Mol Physiol | Volume | 282 |
| Issue | 1 | Pages | L99-108 |
| PubMed ID | 11741821 | Mgi Jnum | J:107840 |
| Mgi Id | MGI:3622369 | Doi | 10.1152/ajplung.2002.282.1.L99 |
| Citation | Crosby JR, et al. (2002) Ectopic expression of IL-5 identifies an additional CD4(+) T cell mechanism of airway eosinophil recruitment. Am J Physiol Lung Cell Mol Physiol 282(1):L99-108 |
| abstractText | CD4(+) T cells have a critical role in the development of allergic pulmonary inflammation, including the recruitment of eosinophils to the airway lumen and interstitium. The expression of interleukin (IL)-5 by CD4(+) cells has, in particular, often been lionized as the central link between allergic inflammation and the concomitant expansion or recruitment of eosinophils. The mechanism(s) by which CD4(+) T cells mediates eosinophil recruitment was assessed with gene knockout mice deficient for T cells or T cell subtypes and a unique IL-5 transgenic mouse (line NJ.1726) that constitutively overexpresses this cytokine in the lung epithelium. Pulmonary IL-5 expression is significantly attenuated in T cell- and CD4(+) but not CD8(+) cell-deficient animals, suggesting an obvious explanation for the lack of eosinophils in the lungs of T cell-deficient and CD4(-/-) mice. However, although the constitutive expression of IL-5 in the lung epithelium of NJ.1726 mice elicited an eosinophilia in the airway lumen of both naive and ovalbumin-treated mice, in the absence of CD4(+) cells, allergen-mediated eosinophil recruitment to the bronchoalveolar lavage fluid was abolished. Moreover, intranasal instillation of the potent eosinophil-specific chemokine eotaxin-2 was incapable of eliciting eosinophil recruitment in naive and ovalbumin-treated NJ.1726 CD4(-/-) mice, suggesting that eosinophil trafficking during allergic inflammatory responses is a consequence of a CD4(+) cell-mediated event(s) in addition to IL-5 expression and the establishment of a pulmonary chemokine gradient. |
