Jove
Visualize
Contact Us
JoVE
x logofacebook logolinkedin logoyoutube logo
ABOUT JoVE
OverviewLeadershipBlogJoVE Help Center
AUTHORS
Publishing ProcessEditorial BoardScope & PoliciesPeer ReviewFAQSubmit
LIBRARIANS
TestimonialsSubscriptionsAccessResourcesLibrary Advisory BoardFAQ
RESEARCH
JoVE JournalMethods CollectionsJoVE Encyclopedia of ExperimentsArchive
EDUCATION
JoVE CoreJoVE BusinessJoVE Science EducationJoVE Lab ManualFaculty Resource CenterFaculty Site
Terms & Conditions of Use
Privacy Policy
Policies

Related Concept Videos

Complement System01:27

Complement System

9.2K
The complement system is a group of approximately 20 plasma proteins that strengthen the body's defenses against infections through opsonization, inflammation, and cell lysis. Opsonization involves coating pathogens with complement proteins, making them more recognizable and facilitating phagocyte engulfment. Certain complement proteins induce inflammation that attracts immune cells to the site of infection. Cell lysis involves the destruction of pathogens through the formation of a...
9.2K
Immune Surveillance by NK Cells and Phagocytes01:25

Immune Surveillance by NK Cells and Phagocytes

7.7K
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...
7.7K
Differentiation of Common Myeloid Progenitor Cells01:15

Differentiation of Common Myeloid Progenitor Cells

3.8K
Common myeloid progenitors (CMPs) are oligopotent cells that can differentiate into granulocytes and macrophages. Granulocytes and macrophages are essential for protecting the body against bacterial, viral, or fungal infections. They migrate from the bone marrow into the circulating blood to reach specific tissue sites where they differentiate and help in immune surveillance. However, they survive only for a few days and must be continuously made available to the organism to maintain a robust...
3.8K
T Cell Types and Functions01:24

T Cell Types and Functions

2.0K
When T cells with CD4 markers are activated, they give rise to two types of effector cells: helper T cells and regulatory T cells. Meanwhile, T cells with CD8 markers differentiate into effector cytotoxic T cells. The differentiation of CD4 T cells into helper T cell subsets, such as Th1, Th2, and Th17 cells, is dependent on the antigen type, antigen-presenting cell, and regulatory cytokines.
Th1 cells stimulate dendritic cells to express necessary co-stimulatory molecules on their surfaces for...
2.0K

You might also read

Related Articles

Articles linked to this work by shared authors, journal, and citation graph.

Sort by
Same author

Neutralizing human monoclonal antibodies that target the PcrV component of the type III secretion system of <i>Pseudomonas aeruginosa</i> act through distinct mechanisms.

eLife·2026
Same author

Efficacy, safety, pharmacokinetics, immunogenicity, and serum neutralizing activity of AZD7442 (tixagevimab-cilgavimab) in patients hospitalized with COVID-19: long-term results from the DisCoVeRy trial.

Clinical microbiology and infection : the official publication of the European Society of Clinical Microbiology and Infectious Diseases·2025
Same author

C1q drives neural stem cell quiescence by regulating cell cycle and metabolism through BAI1.

Nature communications·2025
Same author

The fc fragment of IgMs binds C1q to activate the first step of the classical complement pathway, while inhibiting complement-dependent cytotoxicity.

The FEBS journal·2025
Same author

Sequential emergence and contraction of epithelial subtypes in the prenatal human choroid plexus revealed by a stem cell model.

Nature communications·2025
Same author

Ficolin-1 in pediatric <i>Plasmodium falciparum</i> malaria and its possible role in parasite clearance and anemia.

Infection and immunity·2025

Related Experiment Video

Updated: Jan 3, 2026

Evaluation of the Interplay Between the Complement Protein C1q and Hyaluronic Acid in Promoting Cell Adhesion
06:54

Evaluation of the Interplay Between the Complement Protein C1q and Hyaluronic Acid in Promoting Cell Adhesion

Published on: June 15, 2019

6.3K

Recombinant C1q variants modulate macrophage responses but do not activate the classical complement pathway.

Victoria Espericueta1, Ayla O Manughian-Peter1, Isabelle Bally2

  • 1Department of Biological Sciences, California State University Long Beach, CA, USA.

Molecular Immunology
|November 19, 2019
PubMed
Summary

Complement protein C1q has dual roles in inflammation. Modified C1q variants, unable to activate complement, still promote phagocytosis and reduce inflammatory cytokines, suggesting a distinct therapeutic role.

Keywords:
C1qComplementInflammationMacrophagePhagocytosis

More Related Videos

Isolation Protocol of Mouse Monocyte-derived Dendritic Cells and Their Subsequent In Vitro Activation with Tumor Immune Complexes
11:48

Isolation Protocol of Mouse Monocyte-derived Dendritic Cells and Their Subsequent In Vitro Activation with Tumor Immune Complexes

Published on: May 31, 2018

11.9K
High-resolution Melting PCR for Complement Receptor 1 Length Polymorphism Genotyping: An Innovative Tool for Alzheimer's Disease Gene Susceptibility Assessment
07:26

High-resolution Melting PCR for Complement Receptor 1 Length Polymorphism Genotyping: An Innovative Tool for Alzheimer's Disease Gene Susceptibility Assessment

Published on: July 18, 2017

12.2K

Related Experiment Videos

Last Updated: Jan 3, 2026

Evaluation of the Interplay Between the Complement Protein C1q and Hyaluronic Acid in Promoting Cell Adhesion
06:54

Evaluation of the Interplay Between the Complement Protein C1q and Hyaluronic Acid in Promoting Cell Adhesion

Published on: June 15, 2019

6.3K
Isolation Protocol of Mouse Monocyte-derived Dendritic Cells and Their Subsequent In Vitro Activation with Tumor Immune Complexes
11:48

Isolation Protocol of Mouse Monocyte-derived Dendritic Cells and Their Subsequent In Vitro Activation with Tumor Immune Complexes

Published on: May 31, 2018

11.9K
High-resolution Melting PCR for Complement Receptor 1 Length Polymorphism Genotyping: An Innovative Tool for Alzheimer's Disease Gene Susceptibility Assessment
07:26

High-resolution Melting PCR for Complement Receptor 1 Length Polymorphism Genotyping: An Innovative Tool for Alzheimer's Disease Gene Susceptibility Assessment

Published on: July 18, 2017

12.2K

Area of Science:

  • Immunology
  • Molecular Biology
  • Biochemistry

Background:

  • Complement protein C1q exhibits a dual role in inflammatory diseases like atherosclerosis, with beneficial effects in early stages and detrimental effects in later stages.
  • C1q interacts with phagocytes independently of complement activation, promoting debris clearance and an anti-inflammatory macrophage phenotype, potentially preventing autoimmunity.

Purpose of the Study:

  • To characterize recombinant human C1q (rC1q) variants with mutations at the C1r2C1s2 interaction site, rendering them unable to initiate complement activation.
  • To investigate the structural basis of C1q's interaction with phagocytes by assessing the impact of these mutations on phagocytosis and macrophage polarization.

Main Methods:

  • Created rC1q variants by mutating the C1r2C1s2 interaction site.
  • Assessed phagocytosis of antibody-coated sheep erythrocytes and oxidized LDL by human monocytes and macrophages (HMDM) exposed to wild-type or variant rC1q.
  • Measured secreted cytokine levels in HMDM stimulated with rC1q variants.

Main Results:

  • All C1q variants enhanced phagocytosis in HMDM, similar to wild-type rC1q.
  • Pro-inflammatory cytokine and chemokine secretion by HMDM was modulated by C1q variants, mirroring effects of wild-type rC1q and native C1q.
  • Specific cytokines (IL-1α, IL-1β, TNFα, MIP-1α, IL-12p40) were downregulated by native and rC1q in both resting and M1-polarized HMDM.

Conclusions:

  • The phagocyte-interacting site of C1q is independent of the C1r2C1s2 interaction site.
  • Classical pathway-null C1q variants retain beneficial functions, suggesting potential for therapeutic exploitation.
  • Further research on these variants will elucidate the complement-independent roles of C1q.