Mammalian Cell Culture

<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

Flyer

Brochure

Role of Growth Factors in Cell Differentiation-Poster

Recombinant Mouse IL17

Recombinant Mouse IL-17A by ABM: 16 kDa E. coli-expressed Th17 cytokine, &gt;95% purity by SDS-PAGE, &lt;1.0 EU/µg endotoxin. Bioactivity ED50 &lt;0.5 ng/mL (keratinocyte proliferation). Multiple unit sizes. Supports Th17, NF-κB, and autoimmune disease research. Research use only.

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 IL17, 25 µg

Recombinant Mouse IL17, 100 µg

Recombinant Mouse IL17, 1.0 mg

Growth Factor-eFlyer

Growth Factors and Cytokines-Brochure

Growth Factors and Cytokines-FAQ

Recombinant Mouse IL18

Recombinant Mouse IL-18 by ABM: 18 kDa E. coli-expressed IL-1 superfamily cytokine (IGIF), &gt;95% purity by SDS-PAGE, &lt;1.0 EU/µg endotoxin. Multiple unit sizes. Supports NK cell cytotoxicity assays, inflammasome biology, NF-κB signaling, and IFN-γ induction research. Research use only.

Recombinant Mouse IL18, 5 µg

Recombinant Mouse IL18, 25 µg

Recombinant Mouse IL18, 1.0 mg

Recombinant Mouse IL18BP

Z200429 by Applied Biological Materials is Recombinant Mouse IL-18 Binding Protein (IL-18BP), an E. coli-expressed ~45 kDa natural IL-18 inhibitor with &gt;95% purity by SDS-PAGE, endotoxin &lt;1.0 EU/µg (LAL), supplied in PBS solution — used for IL-18 pathway inhibition, autoimmune disease models, and NLRP3 inflammasome research.

Unit Quantity

Recombinant Mouse IL1A

Recombinant Mouse IL-1A (Z200095) by ABM — 18 kDa, E. coli, Mouse (M. musculus), &gt;95% purity, tag-free. D10.G4 T cell ED50 10.0 pg/mL for NF-kB and inflammation research.

Recombinant Mouse IL1A, 10 µg

Recombinant Mouse IL1A, 100 µg

Recombinant Mouse IL1A, 1.0 mg

Recombinant Mouse IL1B

Z200105 by Applied Biological Materials is recombinant mouse IL1B (IL-1 beta, M. musculus), a tag-free pro-inflammatory cytokine expressed in E. coli. At 17 kDa with &gt;95% purity, endotoxin &lt;1.0 EU/µg, and ED50 ≤2.0 pg/mL (specific activity ≥5.0 × 10⁸ units/mg), it is suitable for NLRP3 inflammasome, NF-kB, and neuroinflammation research. Lyophilized from 0.2 µm filtered PBS, pH 7.

Recombinant Mouse IL1B, 10 µg

Recombinant Mouse IL1B, 100 µg

Recombinant Mouse IL1B, 1.0 mg

Recombinant Mouse IL2

Recombinant Mouse IL-2 (Z200135) by ABM — 17 kDa, E. coli, Mouse (M. musculus), &gt;95% purity, tag-free. CTLL-2 ED50 &lt;0.1 ng/mL. T cell proliferation, Treg expansion, and NK cell research.

Recombinant Mouse IL2, 20 µg

Recombinant Mouse IL2, 100 µg

Recombinant Mouse IL2, 1.0 mg

Recombinant Mouse IL25

Z200255 by Applied Biological Materials is Recombinant Mouse IL-25 (IL-17E), a 16 kDa E. coli-expressed, tag-free cytokine (10 µg lyophilized) with &gt;95% purity by SDS-PAGE, endotoxin &lt;1.0 EU/µg (LAL), and bioactivity ED50 &lt;0.5 ng/mL — for type 2 immunity, allergy, and mucosal immunology research. UniProt Q9CPT4.

Recombinant Mouse IL25, 10 µg

Recombinant Mouse IL25, 100 µg

Recombinant Mouse IL25, 1.0 mg

Recombinant Mouse IL3

Recombinant Mouse IL-3 (Z200145) by ABM — 15 kDa, E. coli, Mouse (M. musculus), &gt;95% purity, tag-free. M-NFS-60 ED50 &lt;0.05 ng/mL. Hematopoiesis and mast cell research.

Recombinant Mouse IL3, 10 µg

Recombinant Mouse IL3, 1.0 mg

Recombinant Mouse IL33

Recombinant Mouse IL-33 Z200155 by ABM—tag-free, E. coli-expressed IL-1 family alarmin, 18 kDa, &gt;95% purity, ED50 ≤0.3 ng/mL. Available from MBP INC.

Recombinant Mouse IL33, 10 µg

Recombinant Mouse IL33, 100 µg

Recombinant Mouse IL33, 1.0 mg

Recombinant Mouse IL4

Recombinant Mouse IL4 (Z200165) by ABM — 14 kDa E. coli-expressed Th2 cytokine, >95% pure, ED50 ≤0.4 ng/mL, BSF-1. Order from MBP INC.

Recombinant Mouse IL4, 10 µg

Recombinant Mouse IL4, 1.0 mg

Recombinant Mouse IL5

Z200475 by Applied Biological Materials (ABM) is a recombinant mouse IL-5 expressed in insect cells, 13 kDa, tag-free, with greater than 95% purity by SDS-PAGE and endotoxin below 1.0 EU/µg. ED50 ≤0.2 ng/mL in TF-1 cell proliferation assay; specific activity ≥6.0 × 10⁶ units/mg.

Recombinant Mouse IL6

Recombinant Mouse IL-6 (Z200175) by ABM — 22 kDa, E. coli, Mouse (M. musculus), &gt;95% purity, tag-free. Hybridoma ED50 &lt;0.05 ng/mL. JAK/STAT3, Th17, and B cell research.