Related Experiment Video

Updated: Oct 3, 2026

Experimental Analysis of Apoptotic Thymocyte Engulfment by Macrophages
06:47

Experimental Analysis of Apoptotic Thymocyte Engulfment by Macrophages

Published on: May 24, 2019

Difference in the way of macrophage recognition of target cells depending on their apoptotic states

C Fujii1, A Shiratsuchi, J Manaka

  • 1Graduate School of Natural Science and Technology, Kanazawa University, Takara-machi, Kanazawa, Ishikawa 920-0934, Japan.

Cell Death and Differentiation
|November 1, 2001
PubMed

Insights

Researchers identified PH2, a novel phagocytosis marker on late apoptotic cells. This marker aids macrophage recognition and engulfment, working alongside phosphatidylserine to clear dying cells.

Area of Science:

  • Cell biology
  • Immunology
  • Apoptosis research

Background:

  • Phagocytosis is crucial for removing dying cells.
  • Phosphatidylserine is a known phagocytosis marker.
  • Other markers may cooperate with phosphatidylserine.

Purpose of the Study:

  • To identify novel phagocytosis markers.
  • To characterize the function of the PH2 antibody.
  • To understand cell surface changes during apoptosis.

Main Methods:

  • Generation of monoclonal antibody PH2.
  • Inhibition assays of macrophage phagocytosis.
  • Flow cytometry to assess PH2 binding to apoptotic cells.

Main Results:

  • PH2 inhibited phagocytosis of late apoptotic/necrotic cells, not early apoptotic cells.
  • PH2 binds preferentially to late-stage apoptotic cells.
  • PH2 is a novel marker translocating to the cell surface during late apoptosis.

Conclusions:

  • PH2 is a novel phagocytosis marker.
  • PH2 facilitates macrophage recognition and engulfment of late apoptotic cells.
  • PH2 complements phosphatidylserine in the clearance of dying cells.

More Related Videos

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

Quantification of Efferocytosis by Single-cell Fluorescence Microscopy06:15

Quantification of Efferocytosis by Single-cell Fluorescence Microscopy

Published on: August 18, 2018

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.
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 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...
Overview of Cell Death01:30

Overview of Cell Death

Cell death is an essential process where the body gets rid of old or damaged cells. Cell proliferation and death need to be balanced, as an imbalance between the two may lead to cancer or autoimmune diseases.
Cell death was observed in the early 19th century, but there was no experimental evidence to prove it. In 1842, Carl Vogt first discovered cell death in a metamorphic toad; however, it was not termed ‘cell death.’ Scientists discovered different cell death pathways only in the 20th century...
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.
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...