Antibody-dependent Phagocytosis
Antibody-dependent Phagocytosis - Related Videos
04:03
An In Vitro Assay to Measure Antibody-Dependent Cellular Phagocytosis by Phagocytes
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2025
This video demonstrates an assay to measure the antibody-dependent cellular phagocytosis (ADCP) by breast milk phagocytes. Fluorescently labeled microspheres conjugated to an antigen-antibody complex, are combined with a cell suspension isolated from breast milk to induce antibody-dependent cellular phagocytosis by the phagocytic leukocytes. Upon labeling the cells with antibodies against common leukocyte antigen (CD45), flow cytometry is used to measure the fluorescence intensity of...
06:56
An Assay for Quantifying Antibody-Mediated Phagocytosis of Parasite-Infected Erythrocytes
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2025
This video demonstrates a flow cytometry-based phagocytosis assay involving labeled and opsonized Plasmodium falciparum-infected erythrocytes by monocytes. Flow cytometry identifies fluorescence in monocytes, confirming the successful identification of opsonized erythrocytes through phagocytosis.
08:12
Isolation of Leukocytes from Human Breast Milk for Use in an Antibody-dependent Cellular Phagocytosis Assay of HIV Targets
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Cited by 2 •
2019
Breast milk transmits human immunodeficiency virus (HIV), though only ~15% of infants breastfed by HIV-infected mothers become infected. Breastfed infants ingest ~105−108 maternal leukocytes daily, though these cells are understudied. Here we describe the isolation of breast milk leukocytes and an analysis of their phagocytic capacity.
03:18
Antibody-Dependent Enhancement of Zika Virus by Dengue Antibodies in Human Primary Macrophages
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2026
Source: Asad, S., et al. Quantification of Antibody-dependent Enhancement of the Zika Virus in Primary Human Cells. J. Vis. Exp. (2019)This video demonstrates antibody-dependent enhancement of Zika virus infection in human primary macrophages, using dengue antibody–virus complexes to model how cross-reactive antibodies facilitate Fcγ receptor–mediated viral entry and replication for studying infection mechanisms and immune interactions.
05:35
An In Vitro Assay to Examine the Antibody-Dependent Enhancement of Viral Infection
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2025
This video demonstrates an assay to measure antibody-dependent enhancement (ADE) of Dengue virus infection using Zika Virus Convalescent Serum. The assay uses Dengue reporter viral particles (RVPs) encoding a green fluorescent protein. Serum antibodies against the Zika Virus cross-react with RVPs to form a complex. The bound antibodies enhance RVP uptake by cells expressing the Fc receptor, which is detected using flow cytometry.
FAQs
The Fab regions provide target recognition by binding antigens on a microbe or cell, whereas the Fc regions remain exposed after binding. This arrangement allows the antibody to connect the target with Fc gamma receptors on a phagocyte. Separating recognition from receptor engagement gives the immune system a way to direct cellular uptake toward antigen-bearing material.
When exposed IgG Fc regions engage Fc gamma receptors, signaling promotes actin-dependent changes in the phagocyte. Actin rearrangement drives the cell membrane around the antibody-coated target and supports its internalization into a phagosome. Thus, receptor binding does more than attach the phagocyte to its target: it triggers the cellular machinery required for uptake.
The phagosome proceeds toward degradation by fusing with lysosomes. This creates an intracellular compartment in which acidification, enzymes, and reactive molecules act on the internalized material. The sequence is important because uptake alone does not ensure destruction; delivery to a lysosome-containing compartment provides the conditions that help eliminate microbial or cellular targets.
Macrophages, neutrophils, and other phagocytic cells can respond when their Fc gamma receptors encounter exposed IgG Fc regions. Their participation connects antibody recognition with innate cellular effector activity. In infection research, this relationship helps explain how antigen-specific antibodies can direct different types of phagocytes toward coated microbial targets.
A useful conceptual sequence is to examine antibody coating of a target, Fc gamma receptor engagement by a phagocyte, actin-dependent uptake, phagosome formation, and subsequent lysosomal processing. Following these linked stages distinguishes target recognition from internalization and destruction, helping researchers interpret whether an antibody response promotes cellular clearance rather than merely antigen binding.
Antibody-based therapies can use the same recognition-to-effector connection to recruit innate immune cells against diseased or abnormal targets. An antibody can bind a selected cellular antigen through its Fab region while exposing Fc regions for phagocyte receptors. This provides a mechanism by which therapeutic antibodies may promote uptake and elimination of targeted material.