<h2 data-section-id="pdko8n" data-start="0" data-end="50">What are recombinant proteins for cell culture?</h2>
&nbsp;
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.
&nbsp;
<h2 dir="ltr">What you will find:</h2>
&nbsp;
<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>
&nbsp;
<h2 data-section-id="4x59d8" data-start="1050" data-end="1118">How to choose recombinant proteins, cytokines, and growth factors</h2>
&nbsp;
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>
&nbsp;
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 Human Leptin (LEP)

Recombinant Human Leptin (LEP / OB), catalog Z101855 by ABM. E. coli-expressed, 16.4 kDa, >95% purity, lyophilized. Bioactive adipokine, ED50 &lt;0.5 ng/mL. Endotoxin &lt;1.0 EU/µg.

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 Human Leptin (LEP), 200 µg

Recombinant Human Leptin (LEP), 1.0 mg

Recombinant Human Leptin (LEP), 2.0 mg

Recombinant Human Lymphotactin  (XCL1)

Z100615 by ABM — Recombinant Human Lymphotactin (XCL1), 10 kDa, tag-free, expressed in E. coli. Purity &gt;95% by SDS-PAGE, endotoxin &lt;1.0 EU/µg, T-cell chemotaxis confirmed at 50–100 ng/mL. Available in 20 µg and 1.0 mg.

Recombinant Human Lymphotactin  (XCL1), 20 µg

Recombinant Human Lymphotactin (XCL1), 1.0 mg

Recombinant Human M-CSF (CSF1)

Z100655 by Applied Biological Materials is a recombinant human M-CSF (CSF1) expressed in E. coli, supplied as a lyophilized non-glycosylated disulfide-linked homodimer (~37.1 kDa, 2 × 159 aa) at &gt;95% purity. M-CSF drives monocyte-to-macrophage differentiation, M2 polarization, osteoclastogenesis, and iPSC macrophage generation through CSF1R signaling.

Recombinant Human M-CSF (CSF1), 10 µg

Recombinant Human M-CSF (CSF1), 1.0 mg

Recombinant Human MANF

Recombinant Human MANF (Z102065) by ABM — E. coli-expressed, 18.4 kDa, PBS formulation. ER-stress-responsive neurotrophic factor for neuroprotection, UPR, and beta-cell biology research. 40 µg.

Recombinant Human MANF, 40 µg

Recombinant Human MANF, 200 µg

Recombinant Human MANF, 1.0 mg

Recombinant Human MCP-2 (CCL8)

Z100635 by ABM — Recombinant Human MCP-2 (CCL8), 9 kDa, tag-free, expressed in E. coli. Purity &gt;95% by SDS-PAGE, endotoxin &lt;1.0 EU/µg, ED50 &lt;0.05 ng/mL. Available in 25 µg, 250 µg, and 1.0 mg formats.

Recombinant Human MCP-2 (CCL8), 25 µg

Recombinant Human MCP-2 (CCL8), 250 µg

Recombinant Human MCP-2 (CCL8), 1.0 mg

Recombinant Human MCP-3 (CCL7)

Recombinant human MCP-3 / CCL7 (Z101915) by ABM — 9.2 kDa, E. coli, &gt;95% purity, tag-free. CC chemokine for monocyte, dendritic cell, and T cell chemotaxis research.

Recombinant Human MCP-3 (CCL7), 10 µg

Recombinant Human MCP-3 (CCL7), 100 µg

Recombinant Human MCP-3 (CCL7), 1.0 mg

Recombinant Human MCP-4 (CCL13)

Z100645 by Applied Biological Materials is a recombinant human MCP-4 (CCL13) CC chemokine expressed in E. coli, supplied lyophilized at &gt;95% purity with endotoxin &lt;0.1 EU/µg. MCP-4 activates CCR2, CCR3, and CCR5 to drive monocyte, eosinophil, and T-lymphocyte chemotaxis, making it the standard reagent for chemokine migration assays, allergy modeling, and receptor-binding studies.

Recombinant Human MCP-4 (CCL13), 25 µg

Recombinant Human MCP-4 (CCL13), 100 µg

Recombinant Human MCP-4 (CCL13), 1.0 mg

Recombinant Human MEC (CCL28)

Recombinant Human MEC (CCL28) Z101025 by ABM — E. coli-expressed, 12 kDa, 2–10 ng/mL human lymphocyte chemoattraction. For mucosal immunity, IgA biology, and CCR10 receptor research. 20 µg or 1.0 mg.

Recombinant Human MEC (CCL28), 20 µg

Recombinant Human MEC (CCL28), 1.0 mg

Recombinant Human MIA

Z102045 by Applied Biological Materials (ABM) is a tag-free recombinant human MIA (Melanoma Inhibitory Activity) protein expressed in E. coli, with greater than 95% purity by SDS-PAGE, a molecular weight of 12.4 kDa, and endotoxin below 1.0 EU/µg. Supplied as lyophilized powder for melanoma biology, rheumatoid arthritis, and cartilage research.

Recombinant Human MIA, 20 µg

Recombinant Human MIA, 1.0 mg

Recombinant Human MIA2

Z102055 by Applied Biological Materials is recombinant human MIA2 (Melanoma Inhibitory Activity-2 / CTAGE5), a tag-free liver-expressed ECM protein produced in E. coli. At 11.7 kDa with &gt;95% purity and endotoxin &lt;1.0 EU/µg, it is evaluated as a potential hepatic disease marker. Lyophilized from 20 mM phosphate buffer, 150 mM NaCl, pH 7.

Recombinant Human MIA2, 20 µg

Recombinant Human MIA2, 1.0 mg

Recombinant Human MIF

Z100915 by Applied Biological Materials (ABM) is a tag-free recombinant human MIF (Macrophage Migration Inhibitory Factor) expressed in E. coli, with greater than 95% purity by SDS-PAGE, 15 kDa molecular weight, and biological activity confirmed by CD74 binding ELISA. Supplied as lyophilized powder for innate immunity, autoimmune disease, and tumor biology research.

Recombinant Human MIF, 25 µg

Recombinant Human MIF, 100 µg

Recombinant Human MIF, 1.0 mg

Recombinant Human MIG  (CXCL9)

Z100665 by Applied Biological Materials is E. coli-expressed recombinant human MIG (Monokine Induced by Gamma Interferon / CXCL9 / CMK / HuMIG), an IFN-γ–inducible CXC chemokine that signals through CXCR3 to attract activated T cells and NK cells. Purity &gt;95% by SDS-PAGE; endotoxin &lt;1.0 EU/µg by LAL. Contact MBP for pricing and pack sizes.