ELISA

We offer full-service development of ELISAs for measuring specific antibodies or antigens. We can transfer an existing ELISA into our lab.

Different Types of ELISAs Can Be Developed:

  • Sandwich ELISAs
  • Double-sandwich ELISAs
  • Competitive ELISAs
  • Secondary Ab coupled to enzyme (HRP, etc.)
  • Ab from the sample
  • Drug

Direct Sandwich ELISA

Direct Sandwich ELISA

Indirect Sandwich ELISA

Bridging ELISA

Several Assay Formats Can Be Developed:

  • Quantitative assays: an accurate standard is available for generation of a calibration curve (such as the toxicokinetics of an administered compound or fluid concentration of antigens like cytokines or other soluble makers).
  • Quasi-quantitative: an accurate standard is not available. This is often the case for immunogenicity studies where no standard can be obtained. Two approaches can be used, depending on the availability of specific polyclonal or monoclonal antibodies from the same animal species:
    • If polyclonal/monoclonal antibodies are not available, a titration approach can be developed.
    • If polyclonal/monoclonal antibodies are available, a calibrating curve can be generated after defining its concentration in arbitrary units.

Validation of a Specific ELISA Includes:

  • Intra-/inter-assay variability
  • Determination of upper and lower detection limits
  • Repeatability, intermediate precision
  • Assay cut-point determination
  • QC acceptance criteria
  • Linearity
  • Sample stability
  • Recovery
  • Matrix interference

Main Guidelines:

  • FDA/CDER/May 2001 “Bioanalytical Method Validation”
  • ICH Q2(R1) 2005 (previously Q2A/B) “Validation of Analytical Procedures: Text and Methodology”

ELISA Applications for Toxicokinetics:

If ELISAs are performed during preclinical studies, regulatory bodies require these assays to be GLP validated and tested. We offer a custom approach to developing and validating a specific sandwich ELISA for your recombinant protein.

Main Guidelines:

  • ICH S3A Oct 1994 “Note for Guidance on Toxicokinetics: The Assessment of Systemic Exposure in Toxicity Studies” ICH S6
  • (CPMP/ICH/302/95) July 1997 “Note for Guidance on Preclinical Safety Evaluation of Biotechnology-Derived Pharmaceuticals”
  • FDA/CDER/May 2001 “Bioanalytical Method Validation” ICH Q2(R1) 2005 (previously Q2A/B) “Validation of Analytical Procedures: Text and Methodology”

Immunogenicity Studies:

During preclinical studies or clinical trials, it is important to evaluate the immunogenicity of biotech products. Using a custom approach, we can develop and validate a specific sandwich ELISA for measuring total and specific immunoglobulins. During the validation, we evaluate the assay cut-off point, sensitivity, intra-/inter-assay variability, and sample stability, among other factors.

Texcell can also assess the seroneutralization capacity for positive samples.

Main Guidelines:

  • ICH S6 (CPMP/ICH/302/95) “Note for Guidance on Preclinical Safety Evaluation of Biotechnology-Derived Pharmaceuticals”
  • EMEA/CHMP/BMWP/246511/2005 “Concept Paper on Guideline on Immunogenicity Assessment of Therapeutic Proteins”
  • FDA/CDER/Oct 2002 Guidance for Industry “Immunotoxicology Evaluation of Investigational New Drugs”
  • Standardization Paper “Recommendation for the design and optimization of Immunoassays used in detection of host antibodies against biotechnology products” A.R. Mire-Sluis et al. / Journal of Immunological Methods 289(2004)1-16
  • FDA/CDER/May 2001 “Bioanalytical Method Validation” ICH Q2(R1) 2005 (previously Q2A/B) “Validation of Analytical Procedures: Text and Methodology”