Along with over a decade of extensive experience in providing excellent custom services for sdAb characterization, Creative Biolabs has won great reputation among our worldwide customers for successfully accomplishing numerous challenging sdAb characterization projects. Equipped with advanced platforms and powerful technologies, we are confident in offering the most suitable solution and achieving the best outcome for our customers.

sdAb Functional Identification

With the efficacy of either antigen-binding region or fused Fc region, sdAb can present various functions. Creative Biolabs offers a full range of functional assays to further analysis and screening sdAb candidates with desired functions.

Typical Function Assays

• Binding assay
• Cell proliferation assay
• Immunomodulation assessment (activation or blocking)
• Neutralization assays (e.g. cytokine, virus, and toxin)
• Immune checkpoint assay
• Endocytosis and internalization assessment
• Effector functions (e.g. ADCC, ADCP, CDC)
• Apoptosis and programmed cell death assessment
• Angiogenesis investigation

De Novo sdAb Sequencing

Equipped with our proprietary database assisted shotgun sequencing (DASS) technology, now Creative Biolabs provides the soluble and functional sdAbs sequencing services with 100% coverage and 100% accuracy.

The DASS system provides reliable supporting proof for QC analysis, IND/NDA application, and confirmation & validation of produced mAb. In order to generate the high-quality results, the high-field Orbitrap Elite hybrid MS (Thermo Scientific) with 240,000 resolution and <1 ppm mass accuracy is used and the alternative fragmentation technologies include CID, HCD, and ETD.

Typical Features

• Fast & Sensitive: The full coverage can be obtained from 50-200 μg sdAbs within 10 working days.
• High-Throughput: Our DASS method enables to plan your project with 100, 200, 500 or more sdAbs.

sdAb Affinity Measurement

Based on the powerful optical phenomena technologies: bio-layer interference (BLI) and surface plasmon resonance (SPR), Creative Biolabs provides the sdAb affinity measurement service with our advanced ProteOn, Biacore, Octet systems, etc.

SPR is an extremely sensitive method which can monitor the binding of any two unlabeled molecules in real time. Combining the sensorgram data with a mathematic model, we are able to calculate the association (K_on ) and dissociation (K_off ) rate constants and finally the binding affinity (K_D).

BLI is an optical analytic approach to determine the biomolecular mutual effect. Apart from the antibody affinity measurement, BLI is also a powerful tool for fragment screening in drug discovery.

sdAb Stability Evaluation

Two of the principal measurable parameters relating to sdAb stability are physical stability (thermodynamic stability) and chemical stability (proteolytic stability). sdAbs with high stability are desirable for therapeutics and vaccines. Now we can provide various stability analytical approaches for our customers.

Stability Evaluation Strategies

• Dynamic light scattering (DLS)
• Differential scanning calorimetry (DSC)
• Differential scanning fluorimetry (DSF)
• Liquid chromatography-mass spectrometry (LC-MS)
• High-performance liquid chromatography (HPLC)

Paratope Mapping

Paratope, also named as an antigen-binding site, is a part of the antibody which allows the recognition and binding to an antigen. Paratope mapping is a powerful technology to understand the antigen-binding site well and plays an important role in vaccines and biotherapeutics discovery.

Paratope Mapping Strategies

• Computational procedure
• Hydrogen-deuterium exchange and mass spectrometry
• Peptide-based approaches
• Hopfield network

Epitope Mapping

Epitopes consist of groups of amino acids which interact with antibodies and therefore determine the antigenicity. Now we can provide the epitope mapping services with 100% accuracy and efficiency.

Epitope Mapping Strategies

• Peptide microarray
• Limited proteolysis coupled with mass spectrometry
• Amide hydrogen/deuterium exchange
• Nuclear magnetic resonance (NMR) analysis
• Surface plasmon resonance
• X-ray crystallography
• Alanine scanning mutagenesis
• Microfluidic peptide microarray
• Surface display methods

Developability Assessment

The unsatisfactory physical and chemical properties of drug molecules result in huge cost during the therapeutic protein discovery. Now, Creative Biolabs has built the comprehensive CreDA™ developability assessment service to avoid the potential clinical failure for your biopharmaceutical candidates.

Our CreDA™ platform consists of two major modules: the preliminary screening stage and the comprehensive assessment stage, which enable the choice of the most appropriate lead molecular for your further processes.

Developability Assessment Strategies

• Preliminary screening
• Comprehensive assessment
• Manufacturability assessment
• Immunogenicity assessment of drug candidates
• In vivo fitness assessment

Based on our integrated platform and professional science teams, Creative Biolabs is always dedicated to assisting our clients with the most satisfactory sdAb characterization services. If you are interested in our service, please feel free to contact us more details.

Reference

1. Henry, K.; et al. Stability-diversity tradeoffs impose fundamental constraints on selection of synthetic human VH/VL single-domain antibodies from in vitro display libraries. Frontiers in immunology. 2017, 8: 1759.

All services are provided for research purposes only. Our services cannot be used for clinical or therapeutic applications.