How Leading Institutions Are Advancing Discovery with Native Human C1Q

 

Complement component C1Q plays a foundational role in a wide range of biological processes—from immune defense to neurodevelopment and tissue regeneration. As a result, native C1Q protein is widely used in biomedical research to explore mechanisms of disease, test therapeutic strategies, and model immune system behavior.

This article highlights how respected institutions around the world are using high-quality C1Q protein in peer-reviewed studies. It also outlines how your research team can access this essential reagent with flexible options for academic and commercial labs alike.

 

C1Q Protein: An Indispensable Tool in Modern Biomedical Research

C1Q is the recognition component of the C1 complex, initiating the classical complement pathway. It binds antibodies, pathogens, apoptotic cells, and synthetic particles—triggering a cascade of immune and inflammatory responses. Its ability to act as a molecular bridge between innate and adaptive immunity has made it a valuable tool in multiple research fields.

Core Research Applications:

• Complement activation and IgG-binding studies
• Antibody and vaccine development
• Nanomedicine and protein corona characterization
• HIV and viral neutralization assays
• Neural repair, aging, and demyelination models
• Stroke and ischemic tissue recovery research

 

Real-World Use: C1Q Protein in Leading Research Institutions

Chinese Academy of Sciences (Beijing, China)
Researchers used native human C1Q in a 2019 Nano Letters study to identify it as a major opsonin shaping the protein corona on cancer nanomedicines.

Study Focus:

C1Q as a dominant opsonin in the protein corona of cancer nanomedicines

Key Concepts:

Protein corona: A layer of biomolecules (mainly proteins) that adsorbs onto the surface of nanoparticles (NPs) when they are introduced into biological fluids. This corona determines how nanoparticles are recognized and processed by the immune system.

Opsonin: A molecule that "tags" foreign materials (like pathogens or nanoparticles) for uptake by phagocytic immune cells.

Main Findings:

Native human C1Q was identified as a major opsonin forming part of the protein corona around various types of cancer-targeted nanoparticles, especially PEGylated liposomes and polymeric micelles.

C1Q binds directly to the nanoparticle surfaces, even in the absence of antibodies, and triggers complement activation, facilitating recognition by phagocytic cells (like macrophages).

The C1Q-mediated opsonization leads to enhanced clearance of nanoparticles by the mononuclear phagocyte system (MPS), especially in the liver and spleen, reducing their circulation time and tumor-targeting efficiency.

Link to article: https://pubs.acs.org/doi/abs/10.1021/acs.nanolett.9b01774

 

University of Southampton (UK)
A 2023 Journal of Immunology publication developed a C1Q affinity chromatography method to evaluate IgG–C1Q interactions, advancing therapeutic antibody research.

Purpose: To create a method to quantitatively evaluate how therapeutic IgG antibodies bind to C1Q — a crucial step in activating the classical complement pathway.

Innovation: Developed a C1Q affinity chromatography assay, allowing precise, reproducible measurement of antibody-C1Q binding.

Impact: This technique improves screening and optimization of therapeutic antibodies by enabling researchers to evaluate their complement activation potential, important for designing antibodies with tailored immune effector functions (e.g., ADCC, CDC).

Link to article: https://journals.aai.org/jimmunol/article/210/11/1837/263652/Development-of-C1q-Affinity-Chromatography-for-the

 

Dartmouth College (USA)
A 2021 mBio study used biotinylated C1Q protein to examine how HIV-neutralizing antibodies recruit complement.

Method: Used biotinylated C1Q protein to study the recruitment of complement by broadly neutralizing antibodies (bNAbs) against HIV.

Findings: Showed that specific bNAbs not only neutralize HIV but also recruit the classical complement pathway, enhancing viral clearance.

Implications: Supports the idea that complement activation is a desirable feature in next-gen HIV antibodies and vaccines.

Link to article: https://journals.asm.org/doi/full/10.1128/mbio.01743-21

 

UCSF & Xyphos Biosciences (USA)
In a 2020 Communications Biology study, scientists used C1Q in cytotoxicity assays to test CAR-T cell therapy platforms.

Application: Incorporated C1Q into cytotoxicity assays to determine how effectively modified CAR-T cells (especially convertibleCAR platforms) trigger complement-mediated cell lysis.

Platform: Xyphos’s “convertibleCAR” system allows modular antigen targeting; C1Q binding assessed complement-related immune functions of these CAR-T cells.

Conclusion: C1Q-mediated complement activation could be used as a functional readout of therapeutic T cell activity and potential off-target effects.

Link to study: https://escholarship.org/uc/item/2cd0685z

 

University of Manitoba & Hebei Medical University (Canada/China)
A 2023 iScience paper described how C1Q protein was used in neural stem cell cultures to promote CNS myelination.

Model: Used C1Q in neural stem cell (NSC) cultures to study central nervous system (CNS) repair and remyelination.

Findings: C1Q promoted oligodendrocyte differentiation and myelin production, suggesting a role beyond immune function — in neurodevelopment and repair.

Relevance: Highlights therapeutic potential for demyelinating disorders like multiple sclerosis, by enhancing endogenous myelination mechanisms.

Link to article: https://www.cell.com/iscience/fulltext/S2589-0042(23)02595-6

Nanjing University Medical School & Shenzhen University (China)
A 2019 study found that C1Q protein promoted angiogenesis following stroke via the LAIR1–HIF1α–VEGF pathway.

Mechanism: C1Q protein enhanced angiogenesis (formation of new blood vessels) after stroke through activation of the LAIR1 (Leukocyte-Associated Ig-like Receptor 1), leading to upregulation of HIF1α and VEGF, both key pro-angiogenic factors.

Outcome: Demonstrated that C1Q is not merely an immune effector but also a regenerative modulator, promoting vascular repair in ischemic brain tissue.

Significance: Suggests that targeting the C1Q–LAIR1–HIF1α–VEGF axis could be a novel stroke therapy approach.

Link to article: https://doi.org/10.2741/4767

 

Supporting Scientific Progress Through Reliable Supply

C1Q protein is a proven research tool across immunology, virology, neuroscience, oncology, and regenerative medicine. As global demand increases, access to consistent, high-quality reagents is more critical than ever.

By working with a reliable supplier, research teams can:

• Ensure quality and batch-to-batch consistency
• Access flexible quantities for both small-scale and large-scale studies
• Obtain technical documentation and responsive support
• Manage research budgets more effectively

Get in Touch

If your lab is exploring complement biology, antibody therapeutics, or neuroimmune interactions, we invite you to learn more about how our C1Q protein can support your research goals.

If you have any questions, concerns, or need assistance placing an order, please don’t hesitate to contact Innovative Research. You can reach us at sales@innov-research.com, by phone at (248) 896-0145, or toll-free at (888) 660-6866. We're here to help you find the best solutions for your research needs.

 

Appendix: Selected Publications

Institution	Year	Journal	Study Focus
Chinese Academy of Sciences	2019	Nano Letters	Opsonization in nanomedicine
University of Southampton	2023	Journal of Immunology	IgG–C1Q affinity analysis
Dartmouth College	2021	mBio	Complement in HIV antibody function
UCSF / Xyphos Biosciences	2020	Communications Biology	CAR-T complement assays
Univ. of Manitoba / Hebei Med. Univ.	2023	iScience	CNS myelination via C1Q
Nanjing Univ. Med School / Shenzhen U	2019	Preclinical study	Post-stroke angiogenesis