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Updated: Jun 27, 2026

Identifying Caspases and their Motifs that Cleave Proteins During Influenza A Virus Infection
08:16

Identifying Caspases and their Motifs that Cleave Proteins During Influenza A Virus Infection

Published on: July 21, 2022

Cathepsin C Restricts Influenza A Virus Replication and Is Associated with Suppression of the PI3K-AKT Signaling

Yansheng Zhu1, Lanlan Si2, Zhongzhong Cao3

  • 1College of Life Sciences, Anhui Medical University, Hefei 230032, China.

Viruses
|June 26, 2026
PubMed

Insights

Cathepsin C (CTSC) protein significantly inhibits influenza A virus (IAV) H1N1 infection. It works by reducing the PI3K-AKT pathway, promoting apoptosis, and limiting viral replication.

Area of Science:

  • Virology
  • Immunology
  • Molecular Biology

Background:

  • Cathepsin C (CTSC) is a lysosomal protease implicated in viral pathogenesis.
  • Its precise antiviral roles and mechanisms against viruses like influenza A virus (IAV) require further investigation.

Purpose of the Study:

  • To investigate the antiviral activity of CTSC against influenza A virus (IAV) H1N1.
  • To elucidate the molecular mechanisms underlying CTSC's antiviral function.

Main Methods:

  • In vitro and in vivo experiments were conducted to assess CTSC's effect on IAV H1N1 infection.
  • The PI3K-AKT signaling pathway was analyzed to understand CTSC's mechanism of action.

Main Results:

  • CTSC demonstrated significant inhibition of IAV H1N1 infection both in vitro and in vivo.
  • CTSC attenuated the PI3K-AKT signaling pathway, leading to increased apoptosis and reduced inflammation.
  • These effects ultimately limited the virus's ability to utilize host resources.

Conclusions:

  • CTSC plays a critical role in the host defense against IAV H1N1.
  • Targeting the PI3K-AKT pathway by CTSC offers a potential therapeutic strategy against H1N1 infection.
Keywords:
Cathepsin CH1N1PI3K-AKT pathwayapoptosisinflammation

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