| First Author | Beamer CA | Year | 2008 |
| Journal | FASEB J | Volume | 22 |
| Issue | 6 | Pages | 2053-63 |
| PubMed ID | 18180331 | Mgi Jnum | J:136538 |
| Mgi Id | MGI:3796463 | Doi | 10.1096/fj.07-095299 |
| Citation | Beamer CA, et al. (2008) Silica suppresses Toll-like receptor ligand-induced dendritic cell activation. FASEB J 22(6):2053-63 |
| abstractText | Inhalation of silica, without evidence of silicosis, is believed to predispose individuals to bacterial infections and impair respiratory immune functions. Silica may alter the sensitivity of antigen-presenting cells (APCs), such as macrophages and dendritic cells (DCs), to other types of infection; however, the exact nature of these exchanges remains uncertain. The purpose of the present study is to characterize the effect of silica exposure on innate pulmonary defense mechanisms following Toll-like receptor (TLR) ligand-induced activation using DCs as a model APC and determine whether these signals act in synergy or opposition to one another. Using C57Bl/6 mice, pattern recognition receptor expression on DCs was examined in vitro and in vivo using flow cytometry, and the activation state of pulmonary and granulocyte-macrophage colony-stimulating factor-derived DCs was assessed in response to silica in combination with TLR ligands (lipopolysaccharide, cytosine-phosphate-guanine, or polyinosinic:polycytidylic acid) using flow cytometry and measurement of cytokine production. In this study, silica attenuated TLR ligand-dependent DC activation with regards to accessory molecule expression as well as nitric oxide and inflammatory cytokine production. Furthermore, silica's ability to modulate TLR ligand-dependent DC activation did not appear to be dependent on the class A scavenger receptors. Taken together, silica's ability to alter susceptibility to infection may be due to impaired inflammatory responses and reduced antibacterial activity. |
