Related Experiment Video

Updated: Jun 19, 2026

Identification of Intracellular Signaling Events Induced in Viable Cells by Interaction with Neighboring Cells Undergoing Apoptotic Cell Death
09:18

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

Published on: December 27, 2016

Decreased CD47 expression during spontaneous apoptosis targets neutrophils for phagocytosis by monocyte-derived

Donald W Lawrence1, Sarah B King, William A Frazier

  • 1Department of Pediatrics, Division of Neonatology, Saint Louis University School of Medicine, Saint Louis, MO 63104, USA.

Early Human Development
|October 10, 2009
PubMed
Abstract

Insights

Neonatal neutrophils show lower CD47 expression, leading to enhanced macrophage phagocytosis compared to adult neutrophils. This age-dependent CD47 expression impacts inflammatory resolution.

Area of Science:

  • Immunology
  • Cell Biology
  • Neonatal Research

Background:

  • Neutrophils are key in acute inflammation and are cleared by macrophages after apoptosis.
  • Efficient clearance of apoptotic neutrophils is crucial for resolving inflammation.
  • CD47's role in apoptotic neutrophil phagocytosis is not fully understood.

Purpose of the Study:

  • To investigate if CD47 influences the targeting of apoptotic neutrophils for phagocytosis.
  • To determine if this CD47-mediated process differs between adult and neonatal neutrophils.

Main Methods:

  • Compared CD47 expression on adult and neonatal neutrophils.
  • Co-cultured apoptotic neutrophils with macrophages to assess phagocytosis using flow cytometry.
  • Investigated CD47 function by blocking its surface expression.

Main Results:

  • Neonatal neutrophils had lower basal CD47 levels than adult neutrophils.
  • Apoptotic neutrophils showed reduced CD47 expression.
  • Macrophages avidly ingested apoptotic neonatal neutrophils over adult neutrophils.
  • Blocking CD47 on neutrophils enhanced macrophage phagocytosis.

Conclusions:

  • Age-dependent CD47 expression on neutrophils influences their phagocytosis by macrophages.
  • Differences in CD47 expression may affect inflammatory resolution in neonates versus adults.

More Related Videos

Development and Identification of a Novel Subpopulation of Human Neutrophil-derived Giant Phagocytes In Vitro10:05

Development and Identification of a Novel Subpopulation of Human Neutrophil-derived Giant Phagocytes In Vitro

Published on: January 25, 2017

Neutrophil Lifespan Extension with CLON-G and an In Vitro Spontaneous Death Assay05:52

Neutrophil Lifespan Extension with CLON-G and an In Vitro Spontaneous Death Assay

Published on: May 12, 2023

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 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...
Immune Surveillance by NK Cells and Phagocytes01:25

Immune Surveillance by NK Cells and Phagocytes

Immune surveillance is an integral part of the innate immune system, involving the continuous monitoring of peripheral tissues to detect and respond to pathogens, infected cells, or cancerous cells. This surveillance is conducted primarily by natural killer (NK) cells and phagocytes, which employ distinct but complementary mechanisms to identify and eliminate threats.
Natural Killer Cells: The Fast Responders
NK cells are large granular lymphocytes found in the blood and lymphatic system. These...
Cells of the Innate Immune Response01:28

Cells of the Innate Immune Response

The innate immune response is an immediate and non-specific response against pathogens, acting swiftly to prevent the spread of infections. The primary cells involved in this response are phagocytes and natural killer (NK) cells.
Phagocytes
Phagocytes police the peripheral tissues by removing cellular debris and responding to the invasion of foreign substances or pathogens. Many phagocytes attack and remove microorganisms even before lymphocytes detect them. The human body has two general...
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...
Cellular Injury V: Apoptosis and Autophagy01:22

Cellular Injury V: Apoptosis and Autophagy

Cells respond to damage and stress through highly coordinated processes that decide whether they survive or undergo controlled self-destruction. Two major pathways involved in this regulation are apoptosis, a type of programmed cell death, and autophagy, a survival mechanism that helps cells adapt to adverse conditions.ApoptosisApoptosis removes aged or injured cells to maintain tissue balance. During this process, the cell shrinks, chromatin condenses and fragments, and membrane-bound...