Transcriptional changes of influenza A/Hong Kong/1/68-H3N2 (HK68) infected A549 lung epithelial cells

Typically viral infections make the host more susceptible to subsequent bacterial infections by mechanisms that are incompletely defined. To identify host changes that occur in response to HK68 infection, gene expression of A549 lung epithelial cells were identified. Changes included an increase in transcripts encoding proteins with fibronectin-type III (FnIII) domains, such as fibronectin (Fn), tenascin N (TNN), and tenascin C (TNC). Results provide insight on the host response to IAV infection, including the production of a variety of ECM proteins, which can create an environment rich in host ligands for bacteria adherence Semi-confluent adenocarcinoma human alveolar basal epithelial cells (A549) cells were infected with influenza virus, A/Hong Kong/1/68-H3N2 (HK68) (5 X10^2 or 2 X 10^5 TCID50), or not (infection media only), and incubated for 30 minutes, 24 hours, or 48 hours at 37°C and 5% CO2. RNA was extracted using Trireagent (LucernaChem) and RNaeasy MiNi Kit (Qiagen, Valencia, CA) as described by manufacturer’s instruction. RNA purity and quantity was confirmed with Agilent chips (Agilent RNA 600 Nano kit). To identify differently expressed genes, fold change was determined by comparing expression levels of IAV infected cells to those obtained with control treated A549 cells. Two independent Codelink microarrays were completed.