Nebulabio is a protein engineering and production team specializing in recombinant protein expression in mammalian systems for research and preclinical discovery workflows. By integrating construct strategy, host selection, and fit-for-purpose process development, we deliver proteins with clear documentation, traceable QC, and reproducible performance across production runs. The working principle is straightforward: clients provide the gene-of-interest (GOI) and intended protein format, and we deliver a mammalian expression solution—together with a complete data package—aligned to the downstream assay needs.

☞Nebulabio’s Mammalian Expression Platform

Mammalian expression is the preferred route for proteins that require native-like folding, secretion, and human-relevant post-translational modifications (PTMs). Our platform covers end-to-end execution from construct review/design to expression testing, production, purification, and characterization. We support rapid transient expression for short timelines and stable-expression routes when repeatable production over time is required. Project execution follows standardized milestones and documentation so that expression decisions are evidence-based and results are reproducible.

☞Supported Expression Options

● Host Cell Lines (HEK293 / CHO / Customer-Provided Lines):

HEK293 is supported for fast expression and broad assay compatibility; CHO is supported for robust secretion and production-like behavior; customer-provided mammalian lines may be accepted after feasibility evaluation (growth, transfectability/transducibility, and target-specific constraints).

● Expression Modes (Transient vs. Stable):

Transient expression is used for rapid access to recombinant proteins for screening or feasibility checks; stable expression (optional) is used when the project requires repeatable production across time, including stable pools or single-cell derived clones.

● Protein Formats (Secreted / Intracellular / Membrane-Associated):

Secreted formats enable harvest from clarified supernatant; intracellular formats enable lysate-based recovery; membrane-associated targets can be supported when an appropriate construct strategy and downstream solubilization plan are defined.

● Vector & Cassette Options (Promoter / Signal / Tag / Co-expression):

Constitutive or inducible promoter architectures can be implemented; secretion signals can be included for extracellular recovery; affinity and detection tags (e.g., His, FLAG, HA, Fc, AviTag) are supported; co-expression designs can be configured for multi-subunit complexes or accessory factors.

● Purification & QC Readouts (Fit-for-Purpose):

Purification may include affinity capture and polishing chromatography (ion-exchange and/or size-exclusion). QC readouts can include SDS-PAGE, SEC-HPLC, Western blot, mass spectrometry (identity), endotoxin (upon request), and project-defined functional or binding assays.

☞Principle of Mammalian Protein Expression

Mammalian expression produces recombinant proteins by introducing an expression cassette carrying the GOI into cultured mammalian cells. The host cell machinery transcribes and translates the GOI, while mammalian processing pathways support correct folding, disulfide bond formation, glycosylation, and trafficking through the secretory system. Depending on construct design, proteins are secreted into the culture medium or retained intracellularly, enabling recovery from supernatant or cell lysate. Compared with prokaryotic expression, mammalian systems are often selected when biological activity, stability, or binding depends on native conformation and PTMs—common in antibodies, Fc-fusions, receptors, and complex glycoproteins.

☞Nebulabio Service Workflow

☞Featured Applications of Our Services

● Therapeutic-format Antibodies & Fc-Fusion Proteins

Mammalian expression is routinely used to produce IgG-like molecules and Fc-fusion proteins where folding, disulfide pairing, and glycosylation patterns can influence binding and stability. For preclinical discovery, these formats support consistent affinity measurement, comparative benchmarking across variants, and downstream developability screens. 

● Structural Biology (Cryo-EM / Crystallography / Biophysics)

For structure-enabled projects, mammalian expression can provide conformationally relevant proteins that better reflect native processing, particularly for glycoproteins and multi-domain constructs. Purified material is typically characterized for homogeneity (SEC profile) to support downstream structural workflows. This application benefits from early format selection (secreted domain vs. full-length) to match structural objectives.

● Vaccine Antigen & Virus-Like Particle (VLP) Production

Manufacture conformationally accurate viral antigens and VLPs for vaccine development and immunogenicity studies.

● Enzymes, Cytokines, and Growth Factors for Cell-Based Assays

Many secreted factors require correct processing for functional activity in cell-based systems. Mammalian expression enables production of these proteins in formats compatible with routine assay workflows, including defined buffer exchange and aliquoting for repeated use. This supports controlled dosing in signaling assays and reduces variability caused by inconsistent reagent quality.

 ● Cell & Gene Therapy Support

Supply recombinant proteins such as growth factors, cytokines, and engineered ligands for cell culture and differentiation protocols.

For inquiries, please reach out to us via email at info@nebulabio.cn or 

by telephone at +86-15801534258.