Antibody Discovery & Bioproduction

  • TARGATT™ HEK293 and CHO Cell Protein Expression

    • TARGATT™ HEK293 Master Cell Line For Site-Specific Knock-in

      TARGATT™ HEK293 Master Cell Line and Knockin Kit - A valuable research tool to generate stable knock-in cell lines!

      The TARGATT™ Knockin Master Cell Line and Kit uses integrase-based integration of a transgene into a preselected intergenic and transcriptionally active genomic locus (hROSA26, hH11, hAAVS1 or other safe harbor loci) engineered with an integrase recognition “attP” docking site or “landing-pad"). Applied StemCell (ASC) provides landing-pad ready TARGATT™ master cell lines and kits.

      The TARGATT™ HEK293 Master Cell Line and Knockin Kit includes a TARGATT™ cloning plasmid that contains an integrase-recognition “attB” sequence and can be used to generate the donor plasmid containing the gene of interest (transgene). When the donor plasmid is transfected into the master cell line along with the integrase expression plasmid (also provided in the kit), the integrase catalyzes the integration of the transgene at the attP-attB sites. This integration is unidirectional which results in a stable integrated knock-in cell line.

      The landing pad in the TARGATT™ HEK293 master cell line is engineered into the well-defined, transcriptionally active, intergenic H11 locus (safe harbor locus/genomic hotspot). This locus enables the high-level expression of the integrated gene-of-interest without disruption of internal genes and gene silencing commonly seen with random integration.

      Advantages of the TARGATT™ HEK293 Master Cell Line:

      • High knock-in efficiency
      • Site-specific integration into the H11 genomic hotspot well-defined safe harbor locus
      • Single gene knockin: one variant - one locus - one cell line
      • Unidirectional integration for stable knock-in cell lines
      • Uniform, high-level gene expression
      • Overcomes challenges such as random insertion, gene silencing, multiple copy gene integration, ablated gene expression.

      The TARGATT™ HEK293 Master Cell Lines and Knockin Kit combines the scalability, affordability, and ease of use of bacterial/yeast systems and the advantages of using mammalian cells (closer to the human environment and post-translational modifications) for efficient and stable gene knockin into cell lines and for library generation. If you would like to learn more, explore our product pages below (AST-1305) or contact us today! 

      If you would like to use your own cell line, our team can engineer the TARGATT™ system into your cell line of choice.

    • Bioproduction: CHO Cells

      TARGATT™ CHO Cells for Recombinant Protein and Antibody Bioproduction! Applied StemCell’s TARGATT™ Master CHO cell lines leverage the site-specific gene integration capacity of serine integrase, phiC31 to knockin transgene(s) into transcriptionally active genomic hotspots, such as the H11 or the proprietary ASC2 (A2) safe harbor locus. These master cell lines enable highly efficient and rapid gene insertion and high levels of recombinant protein/antibody expression. 

      Our Master TARGATT™ CHO cell lines can exceed the capabilities of the traditionally made CHO antibody production cells and offers a platform for affordable and feasible bioproduction for antibodies and other recombinant proteins for companies and projects of all sizes.

      • High knock-in efficiency
      • Site-specific integration into a well-defined safe harbor locus
      • Single gene knocki-n: one variant - one locus - one cell line
      • Unidirectional integration for stable knock-in cell lines
      • Uniform, high-level gene expression
      • Overcomes challenges such as random insertion, gene silencing, multiple copy gene integration, ablated gene expression.

      Licensing and Evaluation Programs Available!

    • Transgenic Animals-Rabbit

      TARGATT™ Rabbit for Biopharming and High-Yield Recombinant Protein and Antibody Production

      Animal bioproduction uses transgenic animal mammary gland as a bioreactor for the production of recombinant proteins. Animal bioproduction, compared to CHO bioproduction, has the advantages of lower upfront and maintenance costs; is easy to contain, control and transport; involves faster development processes and no scale-up issues; and has a unique low-cost bulk holding stage (frozen milk). However, existing technological methods such as random integration to create transgenic animals have many limitations. Applied StemCell has overcome these limitations with our proprietary TARGATT™ technology to reproducibly, and consistently, control the knock-in locus, copy number, and expression of the target protein in transgenic animals.

      Advantages of Animal Bioproduction (Biopharming):

      • Very low upfront investment and low maintenance costs (~10 times lower than CHO)
      • Easy to contain, control and transport
      • Speed of development and expansion
      • No up-scaling problems, size of individual bioreactor constant
      • Technically less demanding
      • Allows complex protein production
      • Unique early low-cost bulk holding stage (frozen milk)
      • Easy protein isolation and purification

      We are excited to use our TARGATT™technology to rapidly engineer your bioproduction animals with your gene of interest. Please contact us for details, pricing, and timelines for your specific project.


  • Antibody Discovery: TARGATT™ HEK293 and CHO Cell-Based Libraries and Monoclonal Antibody Development

    • TARGATT™ CHO and HEK293 Cells For Antibody Library Construction

      TARGATT™ technology enables faster and more efficient site-specific integration of large DNA fragments in cell lines. Our proprietary technology offers an ideal platform for generating stable cell line libraries for mammalian cell display-mediated antibody engineering, protein evolution screening, mammalian two-hybrid (M2H) screens, and more. It allows only a 1:1 variant-to-cell ratio with a uniform and consistent expression of the gene/ protein for efficient screening.

      At ASC, we integrated TARGATT™ site-specific knock-in technology into CHO and HEK293 cells. The TARGATT™ Master CHO and HEK293 Cell Lines enable single-copy insertion at a safe-harbor locus (H11, ASC2). High integration efficiencies and medium to high levels of protein expression have been observed.

      The TARGATT™ master cell lines are ideal for antibody library construction. Our experts have successfully completed several custom TARGATT™ HEK293- and CHO-based library construction projects which have enabled the optimization of our off-the-shelf TARGATT™ HEK293 and CHO library screening kits (Drug selection and FACS kits available). These high-quality kits allow you to build your library in your own lab! Explore our products below or contact us today to schedule your free consultation.

      ASC TARGATT™ Advantages:

      • Single copy knockin: 1 cell, 1 docking site, 1 inserted transgene
      • Site-specific knockin into a high expression, safe harbor locus (H11, ASC2)
      • High efficiency integration (HEK293: >40% without, >90% with drug selection; CHO: ~18% without, >90% with drug selection)
      • Large cell library construction in HEK293/ CHO cells
      • Cost-effective: no virus packaging time and resources
      • BSL1 compatible
      • Fully customizable library construction service
      • Four ready-to-use TARGATT™ antibody library screening kits for you to build your own library

      Licensing and Evaluation Programs Available!

    • Rabbit Monoclonal Antibody Development

      Applied StemCell (ASC) is a fast-growing gene and cell therapy CRO that continuously works to expand its technologies, services, and products to address the current and future needs of the industry and research community. ASC understands that monoclonal antibodies (mAbs) are essential for research and development, so we established and optimized a single B cell antibody discovery platform that can be used to generate high-quality rabbit or alpaca antibodies. Choose from our selection of unique rabbit strains/lines, or ask us about our customized gene knockout rabbit. You can select our classical or accelerated immunization protocol based on your timeline constraints. Once the immunization process is complete, our team conducts single B cell cloning and delivers 40 ELISA positive recombinant mAbs and a data report. You can screen and select your clones of interest, or ASC can complete the screening process for you (*additional fees apply). After antibody selection, our scientists sequence and produce the elected antibodies.

      During your free consultation, our experts can help you design a flexible project outline that captures all of your requirements. Once the project design is finalized, you send us your antigen and we take care of the rest. ASC will have your rabbit monoclonal antibodies in just a few weeks.

      • Rabbit Monoclonal Antibodies with Subnanomolar Affinity
      • HyImmune Rabbits typically produce 3× antigen specific B cells, to increase the antibody development rate
      • Unlimited Supply: Customer owns IP
      • More Antibodies: >0.5mg for each antibody selected
      • Convenient: Antibodies can be delivered with or without luciferase
      • Alpaca Antibody Service Available - Inquire
      • Affordable Pricing
      • Fast turnaround time

      Advantages of ASC's Single B Cell Antibody Discovery Platform

      Monoclonal Antibodies - Unique Animal Strains and Lines

      Unique Animal Strains & Lines

      - LucAb rabbit: produces antibodies with luciferase
      - Hu rabbit: high antibody humanization
      - HyImmune rabbit: enhanced immune response
      - Customized Rabbit Line: gene knockout
      - Alpaca

      Unique Animal Strains & Lines

      Monoclonal Antibodies - Optimized Immunization Protocol

      Optimized Immunization Protocol

      - Accelerated protocol: 4 weeks
      - Classical Protocol: 2-months
      - We ensure antibody affinity & diversity
      - Serum titer monitoring

      Optimized Immunization Protocol

      Monoclonal Antibodies - Single B Cell mRNA Amplification

      Rapid Amplification of Single B Cell mRNA

      - Single B Cell Sorting: 1,000 antigen-specific single B cells/day
      - mRNA Extraction & Amplification: 2 days
      - We guarantee monoclonality
      - Transfection Ready

      Rapid Amplification of Single B Cell mRNA

      Monoclonal Antibodies

      Efficient Mammalian Cell Antibody Expression

      - First Batch: 96 antibodies in 1 week
      - >1,000 antibodies/month
      - ELISA positive antibodies are provided for screening
      - Provided Data: Antibody concentration & ELISA binding

      Efficient Mammalian Cell Antibody Expression

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