About Us

Nebulabio is a specialized cell line engineering team focused on generating high-performance stable production cell lines for recombinant proteins and monoclonal antibodies. By integrating expression cassette engineering, targeted integration technologies, high-throughput screening, and comprehensive clone characterization, we deliver clonal cell lines with high productivity, stable expression, and traceable quality attributes. 

☞Nebulabio Stable Cell Line Development Platform

Stable cell line development provides long-term, scalable production of recombinant proteins and antibodies from a genetically defined cellular substrate. Our platform spans host selection, vector engineering, transfection, pool selection, single-cell cloning, productivity screening, stability evaluation, and cell banking. Both targeted integration and random integration approaches are supported, with screening workflows built to accelerate identification of high-producing and genomically stable clones. The platform is compatible with expectations for cell line characterization and traceability, enabling smooth transition into process development and downstream production workflows.

☞Supported Options

☞Principle of Stable Cell Line Development

Stable cell line development establishes a heritable production system by integrating the gene of interest into the host genome. An expression cassette containing the coding sequence, promoter, and selectable marker is introduced into host cells and incorporated either randomly or via site-specific integration into predefined genomic loci. Following selection, stable pools are generated and evaluated for productivity. Single-cell cloning isolates clonal lines derived from one progenitor cell, enabling genetic homogeneity and consistent production behavior. Lead clones are then characterized for productivity, growth, genetic stability, and product attributes. Selected clones are expanded and banked as cryopreserved cell stocks to provide a consistent substrate for downstream production and further process development.

☞Nebulabio Service Workflow

■ Project Design and Vector Construction

We translate your target molecule and production requirements into a stable cell line development strategy aligned with the intended expression system.

Key Steps

• Host selection based on product class, modification needs, and development context

• Expression cassette design including promoter, signal peptide, selection system, and codon optimization

• Vector construction and sequence verification

• Optional landing-pad preparation for targeted integration workflows

■ Transfection and Pool Generation

We introduce the construct into the host line and establish stable pools under defined selection conditions.

Key Steps

• Host expansion and transfection condition configuration

• Selection using GS DHFR or antibiotic systems as configured

• Pool recovery, productivity tracking, and cryopreservation

• Optional pool enrichment using mini-pools, sorting, or surface strategies when configured

■ Single-Cell Cloning and Monoclonality Documentation

We isolate clonal lines and document monoclonality using imaging or statistically supported approaches.

Key Steps

• Single-cell deposition by FACS or automated pickers

• Imaging-based monoclonality records when configured

• Stepwise expansion with productivity tracking at each scale

• Removal of low-producing or unstable candidates

■ Lead Clone Screening and Rank Ordering

We rank clones for productivity, growth, stability, and product attributes.

Key Steps

• Batch and fed-batch mimic screening for titer and specific productivity

• Growth kinetics, viability, and metabolic profiling

• Product attribute checks including aggregation, charge, and glycosylation features

• Preliminary stability checks under non-selective conditions

■ Clone Characterization and Stability Study

We conduct comprehensive characterization and longer-term stability evaluation on top clones.

Key Steps

• Extended passaging without selection pressure

• Periodic productivity and product attribute monitoring

• Genetic stability checks including copy number and integration features

• Final production clone selection

■ Delivery and Technology Transfer

We deliver cell banks and complete records to support internal manufacturing or external transfer.

Deliverables

• Cryopreserved vials of lead clones and optional MCB WCB sets

• QC certificates and stability summaries

• Full development report covering vector history, transfection, cloning lineage, screening, stability, and product attributes

• Optional transfer support and training when configured

☞Featured Applications

■ Therapeutic Antibody Manufacturing

Stable CHO clones are routinely used to support high-titer production of IgG, bispecific antibodies, and Fc-fusion proteins with consistent product attributes, enabling reliable supply for downstream development and production workflows.

■ Biosimilar and Biobetter Programs

Stable production lines can be developed to match target product profiles and to enable comparability-focused analytics across multiple candidates and process conditions.

■ Recombinant Proteins for Research and Assay Reagents

Stable pools and clones in HEK293 or CHO provide consistent supply of enzymes, cytokines, growth factors, and assay proteins with defined post-translational processing.

■ Vaccine Antigens and Virus-Like Particles

Stable insect or avian systems can support expression of viral structural proteins and assembled particles for development-stage production and assay use.

■ Multisubunit Proteins and Co-Expression Targets

Multi-gene and bicistronic designs enable stable co-expression of complexes, multi-chain antibodies, and pathway components where coordinated expression is required.

■ Metabolic Engineering and Synthetic Biology

Stable integration of pathway modules enables cell factory style expression of complex biomolecules and supports continuous production strategies.