GO:0035696 monocyte extravasation: Mechanism, Genes, Functions and Research Methods
Research-grade guide for scientists and biopharma professionals
Key Takeaways
• GO:0035696 (monocyte extravasation) is defined as the migration of a monocyte from the blood vessels into the surrounding tissue.
• Monocyte extravasation is a multistep process involving tethering, rolling, adhesion, and transmigration, often initiated by neutrophils and regulated by chemokines such as CCL2.
• Key molecules include β2 integrins (e.g., CD11d/CD18), PRMT7, and the IL-33/ST2 axis.
• Dysregulated monocyte extravasation contributes to chronic obstructive pulmonary disease (COPD), breast cancer metastasis, glaucoma, and ischemic stroke.
• Experimental models include organotypic microfluidic devices, knockout mice, and CRISPR-engineered cell lines.
• Targeting monocyte extravasation offers therapeutic potential for inflammatory and neurodegenerative diseases [2,8].
Description
Monocyte extravasation (GO:0035696) is the biological process by which monocytes migrate from the bloodstream into surrounding tissues. This process is essential for immune surveillance, inflammation, and tissue repair, but when dysregulated it contributes to a wide range of pathologies. Understanding the molecular mechanisms of monocyte extravasation is therefore critical for developing targeted therapies. Recent studies have shown that neutrophils can launch monocyte extravasation by releasing granule proteins, and that the arginine methyltransferase PRMT7 promotes monocyte extravasation, leading to tissue injury in chronic obstructive pulmonary disease (COPD). The process is also implicated in cancer metastasis, where CCL2 recruits inflammatory monocytes to facilitate breast-tumour metastasis, and in neurodegeneration, where inhibition of monocyte-like cell extravasation protects from glaucoma. This article provides a comprehensive overview of the definition, mechanisms, key genes, disease associations, and research methods for studying monocyte extravasation.
monocyte extravasation At A Glance
| GO ID | GO:0035696 |
|---|---|
| GO term | monocyte extravasation |
| Ontology | biological_process |
| Synonym | none |
| Major function | Migration of monocytes from blood vessels into surrounding tissue |
| Related process | Leukocyte extravasation, inflammation, immune response |
| Key regulators | CCL2, β2 integrins, PRMT7, IL-33/ST2 |
| Disease relevance | COPD, cancer metastasis, glaucoma, ischemic stroke |
What Is GO:0035696?
According to the Gene Ontology, monocyte extravasation (GO:0035696) is the migration of a monocyte from the blood vessels into the surrounding tissue. This process is a specialized form of leukocyte extravasation and is crucial for monocyte recruitment to sites of inflammation, infection, or injury.
Why Is monocyte extravasation Important in Cell Biology?
Monocyte extravasation is a fundamental step in the immune response, enabling monocytes to reach infected or damaged tissues. However, excessive or inappropriate extravasation drives chronic inflammatory diseases such as COPD, promotes cancer metastasis, and contributes to neurodegeneration. Therefore, understanding and targeting this process is of great therapeutic interest.
• Essential for monocyte recruitment during inflammation and infection.
• Dysregulated in chronic obstructive pulmonary disease (COPD), where PRMT7 promotes extravasation and tissue injury.
• Facilitates breast cancer metastasis via CCL2-mediated monocyte recruitment.
• Inhibition of monocyte-like cell extravasation protects from neurodegeneration in glaucoma.
• IL-33/ST2 signaling in monocyte-derived macrophages helps maintain blood-brain barrier integrity after ischemic stroke.
• β2 integrins such as CD11d/CD18 are key adhesion molecules in staged leukocyte migration.
• Organotypic microfluidic models allow recapitulation of monocyte extravasation to the synovium.
• Non-classical tissue monocytes and interstitial macrophages populate the lung, highlighting heterogeneity.
• Targeting extravasation may reduce tissue damage in inflammatory diseases.
• CRISPR-based models enable functional dissection of genes involved in extravasation.
What Happens During monocyte extravasation?
Initiation by Neutrophils
In simple terms: Neutrophils help monocytes leave blood vessels by releasing proteins.
Neutrophils launch monocyte extravasation by release of granule proteins, which prime the endothelium and facilitate monocyte recruitment.
Chemokine-Mediated Recruitment
In simple terms: Chemical signals attract monocytes to the vessel wall.
CCL2 recruits inflammatory monocytes to facilitate breast-tumour metastasis, demonstrating the role of chemokines in directing extravasation.
Adhesion and Transmigration
In simple terms: Monocytes stick to and cross the blood vessel wall using adhesion molecules.
β2 integrins, such as CD11d/CD18, mediate staged leukocyte migration, including adhesion and transmigration of monocytes.
Regulation by PRMT7
In simple terms: An enzyme called PRMT7 modifies proteins to promote monocyte extravasation.
The arginine methyltransferase PRMT7 promotes extravasation of monocytes, resulting in tissue injury in COPD.
Modulation by IL-33/ST2
In simple terms: A signaling pathway involving IL-33 and ST2 affects monocyte behavior after stroke.
IL-33/ST2 signaling in monocyte-derived macrophages maintains blood-brain barrier integrity and restricts infarctions early after ischemic stroke.
Key Genes Involved in GO:0035696 monocyte extravasation
The following genes and proteins are key players in monocyte extravasation, as supported by published literature.
| Gene | Major Role | Research Relevance |
|---|---|---|
| CCL2 | Chemokine that recruits inflammatory monocytes | Promotes breast cancer metastasis |
| PRMT7 | Arginine methyltransferase | Promotes monocyte extravasation in COPD |
| IL33 | Cytokine | Maintains blood-brain barrier integrity after stroke |
| IL1RL1 (ST2) | IL-33 receptor | Mediates IL-33 signaling in monocytes |
| ITGAD (CD11d) | Integrin subunit | Mediates leukocyte adhesion and migration |
| ITGB2 (CD18) | Integrin subunit | Forms heterodimers with CD11d for adhesion |
| CD14 | Monocyte marker | Used to identify monocytes in extravasation studies |
| LY6C | Monocyte marker | Distinguishes classical and non-classical monocytes |
| CX3CR1 | Chemokine receptor | Involved in monocyte migration |
| CCR2 | CCL2 receptor | Mediates monocyte recruitment |
| SELE | Adhesion molecule | Mediates rolling on endothelium |
| SELL | Adhesion molecule | Mediates tethering and rolling |
| ICAM1 | Adhesion molecule | Binds β2 integrins for firm adhesion |
| VCAM1 | Adhesion molecule | Mediates monocyte adhesion |
| PECAM1 | Adhesion molecule | Facilitates transmigration |
| JAM-A | Junctional adhesion molecule | Regulates transmigration |
| CD99 | Adhesion molecule | Involved in diapedesis |
How Is monocyte extravasation Regulated?
Monocyte extravasation is regulated by a complex interplay of chemokines, adhesion molecules, and intracellular signaling pathways. Neutrophil-derived granule proteins initiate the process. The arginine methyltransferase PRMT7 promotes extravasation, and its inhibition reduces tissue injury in COPD. The IL-33/ST2 axis modulates monocyte-derived macrophage function and blood-brain barrier integrity after stroke. Additionally, β2 integrins such as CD11d/CD18 are dynamically regulated during staged leukocyte migration.
monocyte extravasation and Human Disease
| Gene | Disease / Biology | Potential Experimental Model |
|---|---|---|
| PRMT7 | COPD | Knockout mouse, human monocyte cell line |
| CCL2 | Breast cancer metastasis | Xenograft mouse model, knockout mice |
| IL33/IL1RL1 | Ischemic stroke | Middle cerebral artery occlusion mouse model |
| ITGAD/ITGB2 | Leukocyte adhesion deficiency | Knock-in mouse, patient-derived cells |
| CX3CR1 | Neurodegeneration | CX3CR1-GFP reporter mice |
Chronic Obstructive Pulmonary Disease (COPD)
PRMT7 promotes extravasation of monocytes, resulting in tissue injury in COPD. Targeting PRMT7 may therefore be a therapeutic strategy.
Cancer Metastasis
CCL2 recruits inflammatory monocytes to facilitate breast-tumour metastasis, highlighting the role of monocyte extravasation in cancer progression.
Neurodegeneration and Glaucoma
Inhibition of monocyte-like cell extravasation protects from neurodegeneration in DBA/2J glaucoma, suggesting that blocking extravasation could be neuroprotective.
Ischemic Stroke
IL-33/ST2 signaling in monocyte-derived macrophages maintains blood-brain barrier integrity and restricts infarctions early after ischemic stroke.
From monocyte extravasation-Related Genes to Experimental Models
| Research Question | Suitable Model |
|---|---|
| Does gene X promote monocyte extravasation? | Knockout mouse or CRISPR KO cell line |
| Does a point mutation in gene Y affect extravasation? | Point mutation knock-in via CRISPR |
| How does gene Z overexpression affect extravasation? | Overexpression cell line or transgenic mouse |
| Where is protein W localized during extravasation? | Tagged knock-in (e.g., GFP) via CRISPR |
| What is the transcriptional profile of extravasating monocytes? | RNA-seq of sorted monocytes from tissues |
| Can a drug inhibit monocyte extravasation? | Organotypic microfluidic model |
How to Study the monocyte extravasation Process
| Method | What It Measures | Typical Application |
|---|---|---|
| Transwell migration assay | Number of migrated cells | In vitro screening of chemokines |
| Microfluidic model | Real-time extravasation dynamics | Organotypic synovium model |
| Flow cytometry | Surface marker expression | Identification of monocyte subsets |
| RNA-seq | Transcriptional profile | Gene expression changes during extravasation |
| Intravital microscopy | Monocyte behavior in vivo | Neurodegeneration studies |
| CRISPR knockout | Gene function loss | Target validation |
| Western blot | Protein expression | Validation of knockout/overexpression |
In Vitro Transmigration Assays
Transwell assays and organotypic microfluidic models recapitulate monocyte extravasation to the synovium.
Flow Cytometry and Sorting
Flow cytometry using markers such as CD14, LY6C, and CX3CR1 allows identification and sorting of monocyte populations during extravasation.
Genetic Knockout and Knock-in Models
CRISPR-Cas9 knockout and knock-in mice or cell lines enable functional studies of genes like PRMT7 and CCL2.
Imaging Techniques
Intravital microscopy and immunofluorescence can visualize monocyte extravasation in real time, as shown in glaucoma models.
How CRISPR Can Be Used to Study GO:0035696 monocyte extravasation
Knockout
CRISPR knockout of genes such as PRMT7 or CCL2 can abolish monocyte extravasation, as demonstrated in COPD and cancer models [2,5].
Point Mutation
Introducing point mutations in adhesion molecules like ITGAD can dissect specific domains required for extravasation.
Knock-in
Knock-in of tagged versions of genes (e.g., GFP-CD11d) allows live imaging of protein localization during extravasation.
Overexpression
Overexpression of chemokines like CCL2 can enhance monocyte extravasation and promote metastasis.
How EDITGENE Supports monocyte extravasation Research
Researchers studying monocyte extravasation-related genes often need to determine whether a candidate gene is causally involved in the process. EDITGENE provides a comprehensive suite of CRISPR services to enable such functional studies.
Contact EDITGENE today to design your custom CRISPR model for monocyte extravasation research.
Frequently Asked Questions About monocyte extravasation
What is monocyte extravasation?
Monocyte extravasation (GO:0035696) is the migration of a monocyte from the blood vessels into the surrounding tissue.
What genes are involved in monocyte extravasation?
Key genes include CCL2, PRMT7, IL33/IL1RL1, and integrins such as ITGAD/ITGB2.
How is monocyte extravasation regulated?
It is regulated by chemokines, adhesion molecules, and enzymes like PRMT7, as well as neutrophil-derived factors [1,2,6].
What diseases are associated with monocyte extravasation?
COPD, breast cancer metastasis, glaucoma, and ischemic stroke.
What models are used to study monocyte extravasation?
Transwell assays, microfluidic models, knockout mice, and CRISPR-engineered cell lines.
Can monocyte extravasation be inhibited therapeutically?
Yes, inhibition of monocyte-like cell extravasation protects from neurodegeneration in glaucoma.
What is the role of β2 integrins in monocyte extravasation?
β2 integrins such as CD11d/CD18 mediate staged leukocyte migration, including adhesion and transmigration.
How does PRMT7 affect monocyte extravasation?
PRMT7 promotes extravasation of monocytes, leading to tissue injury in COPD.
What is the role of IL-33/ST2 in monocyte extravasation?
IL-33/ST2 signaling in monocyte-derived macrophages maintains blood-brain barrier integrity after ischemic stroke.
How can CRISPR be used to study monocyte extravasation?
CRISPR knockout, knock-in, point mutation, and overexpression models allow functional dissection of genes involved in extravasation [2,5,6].
Conclusion
Monocyte extravasation (GO:0035696) is a critical biological process with profound implications for immunity and disease. Key molecular players such as PRMT7, CCL2, and β2 integrins have been identified, and their dysregulation contributes to COPD, cancer metastasis, and neurodegeneration. Advanced models, including organotypic microfluidic systems and CRISPR-engineered cells, are enabling deeper mechanistic insights. Targeting monocyte extravasation holds promise for novel therapies.
References
- 1. Soehnlein O et al.. 2009. Neutrophils launch monocyte extravasation by release of granule proteins.. Thromb Haemost 102(2):198-205 PMID: 19652869
- 2. Günes Günsel G et al.. 2022. The arginine methyltransferase PRMT7 promotes extravasation of monocytes resulting in tissue injury in COPD.. Nat Commun 13(1):1303 PMID: 35288557
- 3. Mondadori C et al.. 2021. Recapitulating monocyte extravasation to the synovium in an organotypic microfluidic model of the articular joint.. Biofabrication 13(4) PMID: 34139683
- 4. Wang M et al.. 2024. IL-33/ST2 signaling in monocyte-derived macrophages maintains blood-brain barrier integrity and restricts infarctions early after ischemic stroke.. J Neuroinflammation 21(1):274 PMID: 39449077
- 5. Qian BZ et al.. 2011. CCL2 recruits inflammatory monocytes to facilitate breast-tumour metastasis.. Nature 475(7355):222-5 PMID: 21654748
- 6. Blythe EN et al.. 2021. β2 Integrin CD11d/CD18: From Expression to an Emerging Role in Staged Leukocyte Migration.. Front Immunol 12:775447 PMID: 34858434
- 7. Schyns J et al.. 2019. Non-classical tissue monocytes and two functionally distinct populations of interstitial macrophages populate the mouse lung.. Nat Commun 10(1):3964 PMID: 31481690
- 8. Williams PA et al.. 2019. Inhibition of monocyte-like cell extravasation protects from neurodegeneration in DBA/2J glaucoma.. Mol Neurodegener 14(1):6 PMID: 30670050
