NIOSHTIC-2 Publications Search

Hog confinement dust enhances neutrophil adherence to airway epithelial cells.

Authors
Heires-AJ; Hilger-MA; Wyatt-TA; Von Essen-SG; Romberger-DJ
Source
Am J Respir Crit Care Med 2009 Apr; 179(Meeting Abstracts):A2197
NIOSHTIC No.
20036384
Abstract
Rationale: Persons exposed to swine confinement facilities have evidence of neutrophilic airway inflammation. We previously reported that dust extract from swine facilities is a potent stimulant of interleukin-8 (IL-8) from airway epithelial cells in vitro that is mediated by protein kinase C (PKC) isoforms alpha and epsilon. We hypothesized that dust extract also modulates the ability of neutrophils to adhere to airway epithelium. Methods: Confluent human bronchial epithelial cell monolayers (BEAS-2B) were pre-treated with one of the following agents: anti-ICAM-1 neutralizing antibody or PKC-a or -e specific inhibitors (G6976, RO-318220, respectively) before being exposed to 5% hog confinement dust extract (HDE) for up to 24h. Two epithelial cell lines with inactive PKCa or PKCe (PKCaDN, PKCeDN respectively) were also used. Fresh blood neutrophils (PMN, 300x105/well) labeled with the fluorescent dye calcein-AM were allowed to adhere to the BEAS-2B for 30 minutes. Adherent cells were quantified photometrically. Six wells were averaged for each condition; experiments were repeated 3 times. Multiple comparisons were analyzed using ANOVA with Bonferroni posttest. Results: Adhesion of PMN to BEAS-2B cells treated with HDE was increased in both a time- and dose-dependent fashion. Inhibition of BEAS-2B PKCa using G6976 or the PKCaDN cell line resulted in a 55.4%, and 51.4% reduction in PMN adherence, respectively (p<.01). Likewise, PKCe inhibition by RO-318220 or PKCeDN cells resulted in a 55.8% and 58.1% decrease, respectively (p<.05). Neutralizing antibody blockade of ICAM-1 (1:50 dilution) reduced PMN adherence dose-responsively (68.63%, p<.01). Conclusions: Dust extract mediates PMN adherence predominantly by influencing the epithelium and involves PKC isoforms a and e and ICAM-1.
Keywords
Biological-factors; Cell-biology; Cell-function; Dust-exposure; Dust-inhalation; Exposure-assessment; Exposure-levels; Exposure-methods; Inhalation-studies; Lung-disorders; Lung-function; Lung-irritants; Mathematical-models; Physiological-effects; Physiological-measurements; Pulmonary-system-disorders; Respiratory-hypersensitivity; Respiratory-irritants; Respiratory-system-disorders; Statistical-analysis; Work-environment; Workplace-studies
CODEN
AJCMED
Publication Date
20090401
Document Type
Abstract
Email Address
aheires@unmc.edu
Funding Type
Grant
Fiscal Year
2009
Identifying No.
Grant-Number-R01-OH-008539
ISSN
1073-449X
Priority Area
Agriculture, Forestry and Fishing
Source Name
American Journal of Respiratory and Critical Care Medicine
State
NE
Performing Organization
University of Nebraska Medical Center, Omaha, Nebraska
Page last reviewed: March 11, 2019
Content source: National Institute for Occupational Safety and Health Education and Information Division