Response of Primary Human Airway Epithelial Cells to Influenza Infection: A Quantitative Proteomic Study

Abstract

Influenza A virus exerts a large health burden during both yearly epidemics and global pandemics. However, designing effective vaccine and treatment options has proven difficult since the virus evolves rapidly. Therefore, it may be beneficial to identify host proteins associated with viral infection and replication to establish potential new antiviral targets. We have previously measured host protein responses in continuously cultured A549 cells infected with mouse-adapted virus strain A/PR/8/34(H1N1; PR8). We here identify and measure host proteins differentially regulated in more relevant primary human bronchial airway epithelial (HBAE) cells. A total of 3740 cytosolic HBAE proteins were identified by 2D LC–MS/MS, of which 52 were up-regulated ≥2-fold and 41 were down-regulated ≥2-fold after PR8 infection. Up-regulated HBAE proteins clustered primarily into interferon signaling, other host defense processes, and molecular transport, whereas down-regulated proteins were associated with cell death signaling pathways, cell adhesion and motility, and lipid metabolism. Comparison to influenza-infected A549 cells indicated some common influenza-induced host cell alterations, including defense response, molecular transport proteins, and cell adhesion. However, HBAE-specific alterations consisted of interferon and cell death signaling. These data point to important differences between influenza replication in continuous and primary cell lines and/or alveolar and bronchial epithelial cells.

Lipidomics identifies a requirement for peroxisomal function during influenza virus replication

“…4E ). These fi ndings were consistent with independent studies identifying MFP2/ HSD17B4 (see above), acyl-CoA oxidase 1, and carnitine O-octanoyltransferase as antiviral mediators of infl uenza virus infection ( 5,8,17 ). They further establish the antiviral role of peroxisomal ␤ -oxidation and PPAR ␣ activation and provide a functional explanation for the usage of PPAR ␣ agonists as an alternative treatment for infl uenza virus infection ( 38 ).…”

“…The reduced levels of aPC species in infl uenza virusinfected cells have been previously proposed to be related to impaired aPC biosynthesis as measured by metabolite rates of phospholipid precursors and by global gene and protein expression experiments ( 8,22,23 ). SREBP1, a major regulator of the one-carbon cycle producing the methyl donor S-adenosylmethionine required for the de novo methylation pathway for aPC biosynthesis, was signifi cantly downregulated in infl uenza virus-infected cells ( 22,24 ).…”

“…Infl uenza viruses hijack host cell machineries for efficient replication and acquire a host-derived lipid envelope during budding. Recent systems-scale studies have primarily addressed the individual roles of genes ( 1-5 ) and proteins (6)(7)(8) in this process, yet have failed to illustrate how they function together to generate macromolecular precursors Supernatants and cell lysates were subjected to plaque assay and Western blot at 18 hpi. Cell viability after drug treatment was assessed using Vybrant MTT cell proliferation assay kit (V13154) (Invitrogen®, Life Technologies Co., San Diego, CA) according to the manufacturer's protocol.…”

Differential proteomic analysis of respiratory samples from patients suffering from influenza

“…These results are consistent with Andrea L. Kroeker's study [19] who reported that the down regulated proteins generally belong to cell adhesion and lipid metabolism. The proteins from pandemic influenza A/H1N1/2009 are MAPK7, Zinc finger proteins, Pyruvate dehydrogenase kinases and Beta-defensin 108B are mostly involved in anti-viral mechanism [10,20,28] and also help in host defense system.…”

“…Most proteomic studies investigating the effect of influenza infection have been carried out in different cell lines and primary macrophages. Till date, however, only one scientific report [19] has been documented in literature studying nasal secretions from naturally influenza infected patients. Proteins identified in this study are different from those described in influenza-infected cell lines and primary macrophages [7,22].…”