Dataset Information

Cathepsin B plays a key role in optimal production of the influenza A virus.

ABSTRACT:

Background

Influenza A virus (IAV) is the etiologic agent of the febrile respiratory illness, commonly referred to as 'flu'. The lysosomal protease cathepsin B (CTSB) has shown to be involved in the lifecycle of various viruses. Here, we examined the role of CTSB in the IAV lifecycle.

Methods

CTSB-deficient (CTSB^-/-) macrophages and the human lung epithelial cell line A549 cells treated with CA-074Me were infected with the A/Puerto Rico/8/34 strain of IAV (IAV-PR8). Viral entry and propagation were measured through quantitative real-time RT-PCR; production and localization of hemagglutinin (HA) protein in the infected host cells were analysed by Western blots, flow cytometry and confocal microscopy; production of progeny viruses were measured by a hemagglutination assay.

Results

CTSB^-/- macrophages and CA-074Me-treated A549 cells had no defects in incorporating IAV-PR8 virions and permitting viral RNA synthesis. However, these cells produced significantly lower amounts of HA protein and progeny virions than wild-type or untreated cells.

Conclusion

These data indicate that CTSB is involved in the expression of IAV-PR8 HA protein and subsequent optimal production of IAV-PR8 progeny virions. Targeting CTSB can be a novel therapeutic strategy for treating IAV infection.

SUBMITTER: Coleman MD

PROVIDER: S-EPMC5770218 | biostudies-literature | 2018 Apr

REPOSITORIES: biostudies-literature

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Publications

Cathepsin B plays a key role in optimal production of the influenza A virus.

Coleman Macon D MD Ha Soon-Duck SD Haeryfar S M Mansour SMM Barr Stephen Dominic SD Kim Sung Ouk SO

Journal of virology & antiviral research 20180401 1

<h4>Background</h4>Influenza A virus (IAV) is the etiologic agent of the febrile respiratory illness, commonly referred to as 'flu'. The lysosomal protease cathepsin B (CTSB) has shown to be involved in the lifecycle of various viruses. Here, we examined the role of CTSB in the IAV lifecycle.<h4>Methods</h4>CTSB-deficient (CTSB<sup>-/-</sup>) macrophages and the human lung epithelial cell line A549 cells treated with CA-074Me were infected with the A/Puerto Rico/8/34 strain of IAV (IAV-PR8). Vir ...[more]

PMID: 29349092

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Dataset Information

Cathepsin B plays a key role in optimal production of the influenza A virus.

Background

Methods

Results

Conclusion

Publications

Cathepsin B plays a key role in optimal production of the influenza A virus.

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