title: Exposure of bronchial epithelial cells to whole cigarette smoke: assessment of cellular responses.
abstract: Cigarette smoke is composed of approximately 5% particulate phase and 95% vapour phase by weight. However, routine in vitro toxicological testing of smoke normally only measures the activity of the particulate phase. This study describes a new system for exposing cells at an air-liquid interface to serial dilutions of gaseous smoke. Confluent monolayers of NCI-H292 human lung epithelial cells on semipermeable membranes were placed in a purpose-designed Perspex chamber at an air-liquid interface. The cells were exposed to dilute whole mainstream cigarette smoke for 30 minutes, followed by a 20-hour recovery period. Firstly, high and low delivery cigarettes were compared, and cytotoxicity was determined by using the neutral red uptake assay. Clear differential cytotoxic responses were observed with the two cigarette types, which correlated positively with the concentrations of components in smoke, and particularly compounds in the vapour phase, such as aldehydes. Secondly, low doses of smoke were found to up-regulate mRNA levels of the secreted mucin, MUC5AC, and to stimulate the production of interleukin (IL)-6, IL-8 and matrix-metalloprotease-1, but had no effect on growth-related oncogene alpha. This system will facilitate further investigations into the toxicological mechanisms of cigarette smoke components, and may be useful for studying other gaseous mixtures or aerosols.
authors.affiliation: British American Tobacco, Group R & D Centre, Southampton, UK.
authors.forename: Jeremy
authors.initials: J
authors.lastname: Phillips
authors.forename: Bruno
authors.initials: B
authors.lastname: Kluss
authors.forename: Audrey
authors.initials: A
authors.lastname: Richter
authors.forename: Eian
authors.initials: E
authors.lastname: Massey
mesh_terms: D000230:Adenocarcinoma; D001273:Atmosphere Exposure Chambers; D001980:Bronchi / Q000187:drug effects* / Q000378:metabolism / Q000473:pathology; D045744:Cell Line, Tumor; D002470:Cell Survival / Q000187:drug effects; D017077:Culture Media, Conditioned / Q000737:chemistry / Q000378:metabolism; D016207:Cytokines / Q000378:metabolism; D004305:Dose-Response Relationship, Drug; D015870:Gene Expression / Q000187:drug effects; D006801:Humans; D008175:Lung Neoplasms; D020781:Matrix Metalloproteinase 1 / Q000378:metabolism; D055271:Mucin 5AC; D009077:Mucins / Q000235:genetics / Q000378:metabolism; D009499:Neutral Red / Q000378:metabolism; D011506:Proteins / Q000378:metabolism; D012333:RNA, Messenger / Q000378:metabolism; D020545:Respiratory Mucosa / Q000187:drug effects* / Q000378:metabolism / Q000473:pathology; D020133:Reverse Transcriptase Polymerase Chain Reaction; D012906:Smoke / Q000009:adverse effects*; D014026:Nicotiana; D018675:Toxicity Tests / Q000295:instrumentation / Q000379:methods*
chemical_list: D017077:Culture Media, Conditioned; D016207:Cytokines; C524678:MUC5AC protein, human; D055271:Mucin 5AC; D009077:Mucins; D011506:Proteins; D012333:RNA, Messenger; D012906:Smoke; D009499:Neutral Red; D020781:Matrix Metalloproteinase 1