Related Experiment Video

Updated: Aug 13, 2026

LPS and ATP-induced Death of PMA-differentiated THP-1 Macrophages and its Validation
06:12

LPS and ATP-induced Death of PMA-differentiated THP-1 Macrophages and its Validation

Published on: May 3, 2024

Phospholipase A2 functions in Pseudomonas aeruginosa-induced apoptosis

Susanne Kirschnek1, Erich Gulbins

  • 1Department of Molecular Biology, University of Duisburg-Essen, Hufelandstrasse 55, 45122 Essen, Germany. erich.gulbins@uni-essen.de.

Infection and Immunity
|January 24, 2006
PubMed

Insights

Pseudomonas aeruginosa infection activates cytosolic phospholipase A2 (cPLA2), leading to arachidonic acid release and host cell death. Inhibiting cPLA2 prevents apoptosis, highlighting its role in P. aeruginosa pathogenesis.

Area of Science:

  • Microbiology
  • Cell Biology
  • Immunology

Background:

  • Pseudomonas aeruginosa is a pathogen causing severe infections, particularly in immunocompromised and cystic fibrosis patients.
  • Host cell death pathways are crucial in P. aeruginosa pathogenesis.

Purpose of the Study:

  • To investigate the role of phospholipase A2 (PLA2) activation in P. aeruginosa-induced host cell death.
  • To identify the specific PLA2 isoforms involved in the host response to P. aeruginosa infection.

Main Methods:

  • Assessing arachidonic acid release in epithelial cells and fibroblasts infected with P. aeruginosa.
  • Utilizing specific inhibitors for different PLA2 isoforms (cytosolic PLA2 - cPLA2, iPLA2, sPLA2) to determine their involvement.
  • Evaluating the effect of PLA2 inhibition on P. aeruginosa-induced apoptosis in vitro and in vivo.

Main Results:

  • P. aeruginosa infection activates PLA2, causing increased arachidonic acid release in cultured cells.
  • This activation is specifically mediated by cytosolic PLA2 (cPLA2), not iPLA2 or sPLA2.
  • Inhibitors of cPLA2, but not iPLA2 or sPLA2, prevented P. aeruginosa-induced apoptosis in epithelial cells.
  • Inhibition of apoptosis was also observed in vivo in tracheal epithelial cells during P. aeruginosa infection.

Conclusions:

  • Activation of cPLA2 and subsequent arachidonic acid generation are key mechanisms in P. aeruginosa-induced host cell death.
  • Targeting cPLA2 may offer a therapeutic strategy to mitigate P. aeruginosa-induced tissue damage and infection severity.

More Related Videos

A Liposome Membrane Permeability Assay for Investigating the Effects of Phosphatidylinositol Phosphate Groups on Membranotropic Action of Venom PLA210:31

A Liposome Membrane Permeability Assay for Investigating the Effects of Phosphatidylinositol Phosphate Groups on Membranotropic Action of Venom PLA2

Published on: September 26, 2025

Identification of Intracellular Signaling Events Induced in Viable Cells by Interaction with Neighboring Cells Undergoing Apoptotic Cell Death09:18

Identification of Intracellular Signaling Events Induced in Viable Cells by Interaction with Neighboring Cells Undergoing Apoptotic Cell Death

Published on: December 27, 2016

Related Concept Videos

Phagocytosis of Apoptotic Cells01:17

Phagocytosis of Apoptotic Cells

Cells undergoing apoptosis form apoptotic bodies that must be removed immediately to prevent inflammation, autoimmune diseases, and necrosis. Phagocytosis is carried out by professional phagocytes such as macrophages or  immature dendritic cells. Non-professional phagocytes such as  epithelial cells and fibroblasts also take part in this process; however, they are not as effective as professional phagocytes. 
Normal cells contain receptors that prevent them from being recognized by phagocytes.
The Intrinsic Apoptotic Pathway01:31

The Intrinsic Apoptotic Pathway

Internal cellular stress, such as cellular injury or hypoxia, triggers intrinsic apoptosis. The B-cell lymphoma 2 (Bcl-2) family of proteins are the primary regulators of the intrinsic apoptotic pathway. For example, during DNA damage, checkpoint proteins, such as Ataxia Telangiectasia Mutated (ATM protein) and Checkpoints Factor-2 (Chk2) proteins, are activated. These proteins phosphorylate p53 which further activates pro-apoptotic proteins, such as Bax, Bak, PUMA, and Noxa, and inhibits...
Caspases01:24

Caspases

Caspase, a family of cysteine proteases, serve as effectors in apoptosis. The ced3 gene in C.elegans was first identified to be involved in apoptosis. This gene encodes the ced-3 caspase that is similar to the interleukin-1-beta converting enzyme or ICE in mammals. In addition to apoptosis, caspases also function in the inflammatory response. Inflammatory caspases are essential in activating pro-inflammatory cytokines that recruit immune cells and block the replication of pathogens inside cells.
Apoptosis01:30

Apoptosis

Apoptosis is a combination of two Greek words, 'apo' and 'ptosis,' meaning separation and falling off, respectively. Hippocrates used this word to describe gangrene, which was caused due to bandaging of fractured bones. Apoptosis was distinguished from necrosis in 1970 when John Kerr reported observations of morphological changes occurring during apoptosis. During one experiment, he observed that the disruption of blood supply to the liver tissue resulted in a size reduction of the tissue.
The Extrinsic Apoptotic Pathway01:17

The Extrinsic Apoptotic Pathway

The extrinsic apoptotic pathway is initiated when extracellular death-inducing signals, such as specific cytokines, activate the death receptors expressed on the cell surface. The immune cells involved in this pathway are natural killer cells (NK cells) and cytotoxic T-lymphocytes. NK cells are critical in innate immune response, while cytotoxic T-lymphocytes are associated with adaptive immune response. These cells recognize specific receptors expressed on the altered cells and activate...
Phosphoinositides and PIPs01:42

Phosphoinositides and PIPs

Phosphoinositides are a group of phospholipids containing a glycerol backbone with two fatty acid chains and a phosphate attached to a myoinositol sugar ring. The inositol head group extends into the cytoplasm, where it is modified by adding phosphate groups to form phosphatidylinositol phosphates or PIPs.
Different phosphoinositides are synthesized and recruited on the cytosolic face of the plasma membrane. The localization of specific phosphoinositides concentrated in separate membrane...