First Author | Sunil VR | Year | 2015 |
Journal | Toxicol Appl Pharmacol | Volume | 284 |
Issue | 2 | Pages | 236-45 |
PubMed ID | 25724551 | Mgi Jnum | J:222877 |
Mgi Id | MGI:5645851 | Doi | 10.1016/j.taap.2015.02.002 |
Citation | Sunil VR, et al. (2015) Regulation of ozone-induced lung inflammation and injury by the beta-galactoside-binding lectin galectin-3. Toxicol Appl Pharmacol 284(2):236-45 |
abstractText | Macrophages play a dual role in ozone toxicity, contributing to both pro- and anti-inflammatory processes. Galectin-3 (Gal-3) is a lectin known to regulate macrophage activity. Herein, we analyzed the role of Gal-3 in the response of lung macrophages to ozone. Bronchoalveolar lavage (BAL) and lung tissue were collected 24-72h after exposure (3h) of WT and Gal-3(-/-) mice to air or 0.8ppm ozone. In WT mice, ozone inhalation resulted in increased numbers of proinflammatory (Gal-3(+), iNOS(+)) and anti-inflammatory (MR-1(+)) macrophages in the lungs. While accumulation of iNOS(+) macrophages was attenuated in Gal-3(-/-) mice, increased numbers of enlarged MR-1(+) macrophages were noted. This correlated with increased numbers of macrophages in BAL. Flow cytometric analysis showed that these cells were CD11b(+) and consisted mainly (>97%) of mature (F4/80(+)CD11c(+)) proinflammatory (Ly6GLy6C(hi)) and anti-inflammatory (Ly6GLy6C(lo)) macrophages. Increases in both macrophage subpopulations were observed following ozone inhalation. Loss of Gal-3 resulted in a decrease in Ly6C(hi) macrophages, with no effect on Ly6C(lo) macrophages. CD11b(+)Ly6G(+)Ly6C(+) granulocytic (G) and monocytic (M) myeloid derived suppressor cells (MDSC) were also identified in the lung after ozone. In Gal-3(-/-) mice, the response of G-MDSC to ozone was attenuated, while the response of M-MDSC was heightened. Changes in inflammatory cell populations in the lung of ozone treated Gal-3(-/-) mice were correlated with reduced tissue injury as measured by cytochrome b5 expression. These data demonstrate that Gal-3 plays a role in promoting proinflammatory macrophage accumulation and toxicity in the lung following ozone exposure. |