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Isolation of Salmonella typhimurium-containing Phagosomes from Macrophages
10:33

Isolation of Salmonella typhimurium-containing Phagosomes from Macrophages

Published on: October 25, 2017

Responses of macrophages against Salmonella infection compared with phagocytosis

Maozhi Hu1, Yun Yang, Chuang Meng

  • 1Jiangsu Co-innovation Center for Prevention and Control of Important Animal Infectious Diseases and Zoonoses, Yangzhou University, Yangzhou, 225009, People's Republic of China.

In Vitro Cellular & Developmental Biology. Animal
|August 17, 2013
PubMed

Insights

Live Salmonella enteritidis triggered earlier and stronger host cell responses, including caspase-1 activation and IL-1β release, compared to dead bacteria. This suggests targeting these innate defense pathways could control Salmonella infection.

Area of Science:

  • Immunology
  • Microbiology

Background:

  • Host-pathogen interactions are crucial for understanding infection dynamics.
  • Salmonella enteritidis infection elicits complex macrophage responses.

Purpose of the Study:

  • To compare host macrophage responses to live versus dead Salmonella enteritidis.
  • To identify key cellular pathways involved in Salmonella infection.

Main Methods:

  • Infection of mouse macrophages with live Salmonella enteritidis C50041 and fixed C50041 (C50041-d).
  • Analysis of cytotoxicity, mitochondrial membrane potential, intracellular calcium ions, reactive oxygen species, nitric oxide, LC3 expression, tumor necrosis factor, IL-6, caspase-1 activation, and IL-1β release.

Main Results:

  • Live Salmonella induced stronger cytotoxicity and earlier, more robust cellular responses than dead bacteria.
  • While trends in mitochondrial potential and ion concentrations were similar, live Salmonella led to lower LC3 expression.
  • Live Salmonella significantly inhibited TNF and IL-6 but enhanced caspase-1 activation and IL-1β release.

Conclusions:

  • Host macrophage responses are significantly different between live and dead Salmonella enteritidis.
  • Enhanced caspase-1 activation and IL-1β release by live Salmonella indicate crucial innate defense mechanisms.
  • Targeting the caspase-1/IL-1β pathway presents a potential strategy for controlling Salmonella infections.

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