Search research articles

ABOUT JoVE

Overview Leadership Blog JoVE Help Center

AUTHORS

Publishing Process Editorial Board Scope & Policies Peer Review FAQ Submit

LIBRARIANS

Testimonials Subscriptions Access Resources Library Advisory Board FAQ

RESEARCH

JoVE Journal Methods Collections JoVE Encyclopedia of Experiments Archive

EDUCATION

JoVE Core JoVE Business JoVE Science Education JoVE Lab Manual Faculty Resource Center Faculty Site

Terms & Conditions of Use

Related Concept Videos

Complement System

Complement System

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...

Immune Surveillance by NK Cells and Phagocytes

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...

Differentiation of Common Myeloid Progenitor Cells

Differentiation of Common Myeloid Progenitor Cells

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...

Inflammatory Response

Inflammatory Response

An inflammatory response is a localized, nonspecific immune reaction that occurs when a tissue is injured. It is characterized by redness, swelling, heat, and pain, which are commonly called the cardinal signs and symptoms of inflammation. Inflammation can sometimes result in a loss of function.
Inflammation can be triggered by various stimuli, such as impact, abrasion, chemical irritation, infections, and extreme hot or cold temperatures. These can damage cells and connective tissue fibers,...

You might also read

Related Articles

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

Sort by

Same author

Complement in the Brain: Contributions to Neuroprotection, Neuronal Plasticity, and Neuroinflammation.

Annual review of immunology·2023

Same author

Piecing Complement Together with LEGO Bricks: Impacts on Interest, Confidence, and Learning in the Immunology Classroom.

ImmunoHorizons·2022

Same author

Extracellular signal-regulated kinase 1/2 is required for complement component C1q and fibronectin dependent enhancement of Fcγ- receptor mediated phagocytosis in mouse and human cells.

BMC immunology·2020

Same author

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

Molecular immunology·2019

Same author

Higher Order Architecture of Designer Peptides Forms Bioinspired 10 nm siRNA Delivery System.

Scientific reports·2019

Same author

Complement Nomenclature-Deconvoluted.

Frontiers in immunology·2019

Search research articles

Related Experiment Video

Updated: Apr 24, 2026

Investigation of Macrophage Polarization Using Bone Marrow Derived Macrophages

Investigation of Macrophage Polarization Using Bone Marrow Derived Macrophages

Published on: June 23, 2013

Complement, c1q, and c1q-related molecules regulate macrophage polarization.

Suzanne S Bohlson¹, Sean D O'Conner¹, Holly Jo Hulsebus¹

¹Department of Microbiology and Immunology, Des Moines University , Des Moines, IA , USA.

Frontiers in Immunology

|September 6, 2014

Summary

The complement system significantly influences macrophage polarization. Specific complement molecules like C1q and mannan-binding lectin (MBL) promote anti-inflammatory and pro-resolving macrophage functions.

Keywords:

C1q adiponectin complement cytokine efferocytosis inflammasome macrophage phagocytosis

More Related Videos

Reprograming Model of Human Monocyte-derived Macrophages for In-vitro Assays

Reprograming Model of Human Monocyte-derived Macrophages for In-vitro Assays

Published on: April 18, 2025

Polarization of M1 and M2 Human Monocyte-Derived Cells and Analysis with Flow Cytometry upon Mycobacterium tuberculosis Infection

Polarization of M1 and M2 Human Monocyte-Derived Cells and Analysis with Flow Cytometry upon Mycobacterium tuberculosis Infection

Published on: September 18, 2020

Related Experiment Videos

Last Updated: Apr 24, 2026

Investigation of Macrophage Polarization Using Bone Marrow Derived Macrophages

Investigation of Macrophage Polarization Using Bone Marrow Derived Macrophages

Published on: June 23, 2013

Reprograming Model of Human Monocyte-derived Macrophages for In-vitro Assays

Reprograming Model of Human Monocyte-derived Macrophages for In-vitro Assays

Published on: April 18, 2025

Polarization of M1 and M2 Human Monocyte-Derived Cells and Analysis with Flow Cytometry upon Mycobacterium tuberculosis Infection

Polarization of M1 and M2 Human Monocyte-Derived Cells and Analysis with Flow Cytometry upon Mycobacterium tuberculosis Infection

Published on: September 18, 2020

Area of Science:

Immunology
Cell Biology

Background:

The complement system is crucial for innate and adaptive immunity, regulating various human conditions.
Macrophages act as immune sentinels, responding to pathogens and self-antigens.
Complement components like anaphylatoxins and opsonins modulate macrophage functions.

Purpose of the Study:

To review the influence of the complement system on macrophage polarization.
To highlight the specific roles of C1q and related molecules in macrophage responses.

Main Methods:

Literature review of studies on complement-macrophage interactions.
Analysis of experimental data on complement component effects on macrophage phenotypes.

Main Results:

Anaphylatoxins (C3a, C5a) activate macrophage inflammasomes.
Opsonins (C1q, MBL, adiponectin) downregulate inflammasome activation and inflammation.
Opsonins promote apoptotic cell engulfment, inducing a pro-resolving (M2) macrophage phenotype.

Conclusions:

The complement system differentially regulates macrophage polarization.
C1q and related molecules play a key role in promoting anti-inflammatory and pro-resolving macrophage functions, impacting immune homeostasis.