Related Experiment Video

Updated: Aug 8, 2026

A Simple and Efficient Method to Detect Nuclear Factor Activation in Human Neutrophils by Flow Cytometry
08:26

A Simple and Efficient Method to Detect Nuclear Factor Activation in Human Neutrophils by Flow Cytometry

Published on: April 9, 2013

Protein kinase C controls Fc gamma receptor-mediated endocytosis in human neutrophils

I I Moraru1, M Laky, T Stãnescu

  • 1Division of Cell Biology, Faculty of Medicine, Bucharest, Romania.

FEBS Letters
|November 12, 1990
PubMed

Insights

This study reveals that phospholipase C (PLC) and A2 (PLA2) activation initiates Fc gamma receptor-mediated endocytosis in neutrophils, primarily through protein kinase C (PKC) signaling pathways.

Area of Science:

  • Immunology
  • Cell Biology
  • Biochemistry

Background:

  • Neutrophil endocytosis is crucial for immune responses.
  • Fc gamma receptors (FcγR) mediate the uptake of immune complexes.
  • The precise signaling pathways involved in FcγR-mediated endocytosis require elucidation.

Purpose of the Study:

  • To determine the specific signaling mechanisms underlying Fc gamma receptor-mediated endocytosis in human neutrophils.

Main Methods:

  • Investigated the role of phospholipase C (PLC) and phospholipase A2 (PLA2) using specific antibodies for inhibition.
  • Assessed the involvement of protein kinase C (PKC) by using activators and inhibitors.
  • Evaluated the effect of H-8 on endocytosis to confirm PKC specificity.

Main Results:

  • Antibodies against PLC and PLA2 significantly inhibited endocytosis, with combined use nearly abolishing it (up to 91%).
  • PKC activation reversed the inhibitory effects of PLC and PLA2 antibodies.
  • Specific PKC inhibitors (H-7, palmitoylcarnitine, sphingosine, tamoxifen) dose-dependently inhibited endocytosis (>80%).
  • H-8, a non-PKC inhibitor, had no effect on endocytosis.

Conclusions:

  • Fc gamma receptor-induced endocytosis in neutrophils is triggered by the activation of PLC and PLA2.
  • This process is critically dependent on the subsequent activation of protein kinase C (PKC).

More Related Videos

Quantitative In vitro Assay to Measure Neutrophil Adhesion to Activated Primary Human Microvascular Endothelial Cells under Static Conditions11:22

Quantitative In vitro Assay to Measure Neutrophil Adhesion to Activated Primary Human Microvascular Endothelial Cells under Static Conditions

Published on: August 23, 2013

Rapid Magnetic-microbead Method for Efficient Purification of Low-density Neutrophils08:14

Rapid Magnetic-microbead Method for Efficient Purification of Low-density Neutrophils

Published on: November 11, 2025

Related Concept Videos

NF-κB-dependent Signaling Pathway02:26

NF-κB-dependent Signaling Pathway

The transcription factor NF-κB was discovered in 1986 in the lab of Nobel laureate Professor David Baltimore, for its interaction with the immunoglobulin light chain enhancer in B-cells. After more than three decades of study, it is now evident that NF-κB regulates the expression of over 100 genes. Most of these genes play an essential role in the innate and adaptive immune responses as well as the inflammatory responses of animals.
NF-κB-dependent Signaling Mechanism
The heterodimer of NF-κB...
Receptor Downregulation in MVBs01:15

Receptor Downregulation in MVBs

Multivesicular bodies (MVBs) are mature endosomes that sort ubiquitinated proteins and then fuse with lysosomes to degrade the sorted proteins. Epidermal growth factor (EGF) and its receptor (EGFR) form a complex that can be internalized through endocytosis, sorted into an MVB, and later degraded.
The EGFR can initiate signaling pathways that  lead to cell proliferation, migration, and differentiation. Overexpression of EGFR  stimulates cells to proliferate. Excessive  EGFR activation may...
Amplifying Signals via Enzymatic Cascade01:22

Amplifying Signals via Enzymatic Cascade

When a ligand binds to a cell-surface receptor, the receptor's intracellular domain changes shape, which may either activate its enzyme function or allow its binding to other molecules. The initial signal is amplified by most signal transduction pathways. This means that a single ligand molecule can activate multiple molecules of a downstream target. Proteins that relay a signal are most commonly phosphorylated at one or more sites, activating or inactivating the protein. Kinases catalyze the...
MAPK Signaling Cascades01:07

MAPK Signaling Cascades

Mitogen-activated protein kinase, or MAPK pathway, activates three sequential kinases to regulate cellular responses such as proliferation, differentiation, survival, and apoptosis. The canonical MAPK pathway starts with a mitogen or growth factor binding to an RTK. The activated RTKs stimulate Ras, which recruits Raf or MAP3 Kinase (MAPKKK), the first kinase of the MAPK signaling cascade. Raf further phosphorylates and activates MEK or MAP2 Kinases (MAPKK), which in turn phosphorylates MAP...
IP3/DAG Signaling Pathway01:11

IP3/DAG Signaling Pathway

Membrane lipids such as phosphatidylinositol (PI) are precursors for several membrane-bound and soluble second messengers. Specific kinases phosphorylate PI and produce phosphorylated inositol phospholipids. One such inositol phospholipids are the  phosphatidylinositol-4,5 bisphosphate [PI(4,5)P2], present in the inner half of the lipid bilayer. Upon ligand binding, GPCR stimulates Gq proteins to turn on phospholipase Cꞵ. Activated phospholipase Cꞵ cleaves PI(4,5)P2 and produces two-second...
Intracellular Signaling Affects Focal Adhesions01:17

Intracellular Signaling Affects Focal Adhesions

Integrins act both as extracellular input receivers and as intracellular processing activators. As their name suggests, integrins are entirely integrated into the membrane structure. Their hydrophobic membrane-spanning regions interact with the phospholipid bilayer's hydrophobic region. These membrane receptors provide extracellular attachment sites for effectors like hormones and growth factors. They activate intracellular response cascades when their effectors are bound and active.
Some...