<h2 data-section-id="pdko8n" data-start="0" data-end="50">What are recombinant proteins for cell culture?</h2>
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Recombinant proteins for cell culture are biologically active growth factors, cytokines, and signaling molecules produced using recombinant DNA technology to control specific cellular functions in vitro. Growth factors such as FGF (fibroblast growth factor), EGF (epidermal growth factor), and TGF-&beta; (transforming growth factor beta) regulate cell growth, proliferation, survival, and differentiation. Cytokines including IL-2, IL-7, IL-15, and IL-21 influence immune cell activation, expansion, and function. These proteins are widely used in serum-free and chemically defined media, stem cell and iPSC culture, immune cell expansion, organoid development, hybridoma production, and cell and gene therapy workflows where precise control over cellular signaling is required.
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<h2 dir="ltr">What you will find:</h2>
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<ul>
<li>Includes cytokines, chemokines, growth factors, and signaling proteins to support proliferation, differentiation, and maintenance of&nbsp;mammalian cells</li>
<li>Rat, human, and mouse recombinant proteins compatible with translational research models and diverse mammalian cell culture&nbsp;</li>
<li>Optimizing cell metabolic activity, signalling pathways, and experimental reproducibility in vitro using recombinant proteins&nbsp;</li>
<li>Suitable for organoid development, expansion of cells, activation of immune cells, neuronal studies, and protein expression workflow optimization.</li>
</ul>
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<h2 data-section-id="4x59d8" data-start="1050" data-end="1118">How to choose recombinant proteins, cytokines, and growth factors</h2>
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Quality grade: RUO vs. preclinical vs. GMP
Research-use-only (RUO) proteins are suitable for most academic and industrial research applications. Preclinical-grade proteins provide enhanced documentation and quality control for studies supporting clinical development. GMP-grade proteins are manufactured under controlled quality systems with complete traceability and lot-to-lot bioactivity verification, making them appropriate for cell therapy, gene therapy, and other regulated applications.
Expression system and post-translational modifications
The production system can significantly affect protein activity. HEK293 and other mammalian expression systems preserve native human post-translational modifications such as glycosylation and phosphorylation, which are often necessary for full biological function. Bacterial expression systems such as E. coli may offer lower cost and higher yields but cannot reproduce many of these modifications.
Carrier-free formulation
Carrier-free recombinant proteins are formulated without stabilizing proteins such as bovine serum albumin (BSA). This eliminates potential experimental interference from carrier proteins and supports serum-free, animal-component-free, and GMP-compatible workflows. Carrier-free formulations are especially important when studying sensitive signaling pathways or developing clinical manufacturing processes.
Endotoxin level and purity
Endotoxins can stimulate inflammatory responses and alter cell behavior, particularly in immune cell cultures. For T-cell expansion, stem cell culture, and other sensitive applications, low-endotoxin or endotoxin-free proteins with documented purity above 95% are preferred to ensure reproducible results.
Stability format: standard vs. thermostable
Standard recombinant proteins gradually lose activity during prolonged incubation at 37&deg;C. Thermostable variants, such as engineered FGF2 formulations, maintain biological activity for longer periods and reduce the need for frequent media supplementation. These products can improve workflow efficiency in stem cell maintenance and differentiation protocols.
Storage and reconstitution
Lyophilized recombinant proteins offer extended shelf life and are typically stored frozen until use. After reconstitution, proteins should be aliquoted into single-use portions whenever possible to minimize repeated freeze-thaw cycles that can reduce activity. Proper storage conditions vary by product and should follow the manufacturer's recommendations.
<h2 data-section-id="rxnuuy" data-start="3659" data-end="3704">&nbsp;</h2>
<h2 data-section-id="1fljvas" data-start="4451" data-end="4476">Specifications context</h2>
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Modern recombinant cytokines and growth factors are available in a wide range of formats including carrier-free, low-endotoxin, animal-component-free, and GMP-grade formulations. Many GMP-grade cytokines such as IL-2, IL-7, IL-15, and IL-21 undergo lot-specific bioactivity testing using validated reference standards to ensure consistent biological performance. Mammalian-cell-expressed proteins are increasingly preferred for applications requiring native structure and maximum biological activity.
As of 2026, carrier-free, low-endotoxin recombinant proteins produced in mammalian expression systems have become the preferred choice for stem cell culture, immune cell expansion, organoid development, and advanced biomanufacturing workflows.
For basal media used alongside recombinant proteins, see Classic Media. For additional supplementation reagents, see Cell Culture Supplements &amp; Additives. Browse Mammalian Cell Culture for the broader category.
<a href="https://mbpinc.net/contact-us">Contact the expert team</a> at MBP today and get optimized recombinant proteins for your lab.

Recombinant Proteins

MSDS

Growth Factor-eFlyer

Growth Factors and Cytokines-Brochure

Growth Factors and Cytokines-FAQ

Role of Growth Factors in Cell Differentiation-Poster

Recombinant Mouse CXCL12 (SDF-1 beta)

Recombinant Mouse CXCL12 (SDF-1 beta) by Applied Biological Materials — E. coli-expressed CXC chemokine with &gt;95% purity, endotoxin &lt;1.0 EU/µg, and confirmed T cell chemotactic activity at 5.0–40 ng/mL. Available in multiple sizes for CXCR4 signaling and stem cell research.

Organism

Family

Aliases

Gene Symbol

Gene ID

Accession Number

Source

Species

Appearance

Molecular Weight

Endotoxin Level

Purity

Formulation

Function

Reconstitution

Storage

Usage

Manufacturer

Shipping Condition

Storage Condition

Recombinant Mouse CXCL12 (SDF-1 beta), 10 µg

Recombinant Mouse CXCL12 (SDF-1 beta), 1.0 mg

Recombinant Mouse CXCL2

Recombinant Mouse CXCL2 (Z200355) by ABM — 8 kDa, E. coli, Mouse (M. musculus), &gt;95% purity, tag-free. HepG2 ED50 &lt;0.5 ng/mL. CXCR2-driven neutrophil chemotaxis and inflammation research.

Recombinant Mouse CXCL2, 20 µg

Recombinant Mouse CXCL2, 100 µg

Recombinant Mouse CXCL2, 1.0 mg

Recombinant Mouse CXCL4 (PF4)

Z200305 by Applied Biological Materials (ABM) is a recombinant mouse CXCL4 (PF4) protein expressed in E. coli, 9 kDa, with greater than 95% purity by SDS-PAGE and endotoxin below 1.0 EU/µg. Bioactivity confirmed by inhibition of FGF-basic-dependent fibroblast proliferation at an ED50 of 5–15 µg/mL.

Recombinant Mouse CXCL4 (PF4), 20 µg

Recombinant Mouse CXCL4 (PF4), 1.0 mg

Recombinant Mouse EGF

Recombinant Mouse EGF (Epidermal Growth Factor), catalog Z200025 by ABM. E. coli-expressed, 6.2 kDa, >95% purity, lyophilized. Bioactive EGFR ligand, ED50 ≤0.2 ng/mL. Endotoxin &lt;1.0 EU/µg.

Recombinant Mouse EGF, 500 µg

Recombinant Mouse EGF, 1.0 mg

Recombinant Mouse EGFL7

Recombinant Mouse EGFL7 Z200545 by ABM — 33 kDa insect cell expression, &gt;95% pure by SDS-PAGE, bioactivity confirmed by HUVEC adhesion assay, &lt;1.0 EU/µg endotoxin. Aliases: VE-statin, Zneu1. Ships from MBP INC to USA, Canada, and international labs.

Unit Quantity

Recombinant Mouse Eotaxin  (CCL11)

Z200035 by Applied Biological Materials — recombinant mouse Eotaxin (CCL11/Scya11), E. coli, 8 kDa, tag-free, &gt;95% purity. Eosinophil chemoattractant for allergic inflammation, asthma, and CCR3 signaling research.

Recombinant Mouse Eotaxin  (CCL11), 20 µg

Recombinant Mouse Eotaxin (CCL11), 100 µg

Recombinant Mouse Eotaxin (CCL11), 1.0 mg

Recombinant Mouse Eotaxin-2  (CCL24)

Recombinant Mouse Eotaxin-2 (CCL24) — Z200405 by Applied Biological Materials. E. coli-expressed, &gt;95% pure by SDS-PAGE, 12 kDa, endotoxin &lt;1.0 EU/µg. CCR3 ligand; chemoattracts mouse lymphocytes at 10–100 ng/mL. Available in 20 µg and 1.0 mg.

Recombinant Mouse Eotaxin-2  (CCL24), 20 µg

Recombinant Mouse Eotaxin-2 (CCL24), 1.0 mg

Recombinant Mouse Exodus-2 (CCL21A)

Z200045 by Applied Biological Materials — recombinant mouse Exodus-2 (CCL21A/SLC/6Ckine), E. coli, 12 kDa, tag-free, &gt;95% purity. CCR7 ligand for lymphocyte trafficking, dendritic cell migration, and adaptive immunity research.

Recombinant Mouse Exodus-2 (CCL21A), 20 µg

Recombinant Mouse Exodus-2 (CCL21A), 1.0 mg

Recombinant Mouse FGF1

Recombinant Mouse FGF1 (aFGF), catalog Z200005 by ABM. E. coli-expressed, 16.0 kDa, >95% purity, lyophilized. Pan-FGFR1–4 ligand, ED50 ≤10 ng/mL. Endotoxin &lt;1.0 EU/µg.

Recombinant Mouse FGF1, 50 µg

Recombinant Mouse FGF1, 200 µg

Recombinant Mouse FGF1, 1.0 mg

Recombinant Mouse FGF2

Recombinant Mouse FGF2 (Basic FGF) Z200015 by ABM—tag-free, E. coli-expressed mitogen, 16.5 kDa, &gt;95% purity, ED50 ≤0.2 ng/mL. Available from MBP INC.

Recombinant Mouse FGF2, 50 µg

Recombinant Mouse FGF2, 250 µg

Recombinant Mouse FGF2, 1.0 mg

Recombinant Mouse FGF8

Recombinant Mouse FGF8 by Applied Biological Materials — E. coli-expressed fibroblast growth factor with &gt;95% purity, ED50 0.05–0.5 ng/mL (NIH/3T3 proliferation), and endotoxin &lt;1.0 EU/µg. Available in multiple sizes for stem cell, neurodevelopment, and FGFR signaling research.

Recombinant Mouse FGF8, 50 µg

Recombinant Mouse FGF8, 1.0 mg

Recombinant Mouse FLT3 Ligand (FLT3LG)

Recombinant Mouse FLT3 Ligand (FLT3LG), catalog Z200055 by ABM. E. coli-expressed, 19 kDa, >95% purity, lyophilized. Bioactive FLT3/CD135 ligand, ED50 ~10 ng/mL. Endotoxin &lt;1.0 EU/µg.