Epibase™ In Vitro Assays
Lonza’s Epibase™ In Vitro Immunogenicity Screening Service includes a wide range of assays to assess the immune responses raised by vaccine candidates. The immunogenicity potential of vaccines is evaluated by directly measuring T cell response in the human population using peripheral blood mononuclear cells (PBMCs). By identifying T cell epitopes, Epibase™ In Vitro allows for a direct comparison of the immunogenic profiles of all your vaccine leads. When combined with our Epibase™ In Silico tool, these cellular assays allow for a complete immunogenicity assessment of your vaccine targets. The tools aid in the selection of optimal vaccine leads helping to maximize an effective immunogenic response in humans prior to your first clinical trial.
Epibase™ In Vitro Assays:
- T cells
- B cells
- Antigen presenting cells (APCs)
- Adjuvant assays
- Custom assays
- Clinical immunoprofiling
Designed for a Wide Range of Targets:
- Whole protein / protein complexes
- Whole viruses
- Virus-like particles (VLPs) / virosomes
Advantages of Epibase™ In Vitro Assays:
- Multi-parameter measurement of T cell activation by flow cytometry, ELISPOT and other multiplex methods allow for a detailed characterization of T cell subtypes
- Medium to high throughput processes capable of running a large number of samples
- Stringent quality control to guarantee assay consistency and traceability of each sample
- Consistent supply of blood samples from healthy donors
Human PBMC Bank
The Epibase™ In Vitro assays use human peripheral blood mononuclear cells (PBMCs) providing researchers with an immune response that closely resembles the response in a human. For the Epibase™ In Vitro assays, whole blood is collected at clinical sites adhering to ethically approved protocols.
- PBMCs isolated and cryopreserved within 6 hours of blood withdrawal
- Preparations genotyped to a 4-digit level at HLA Class I and II loci
- Stringent quality control analysis, including cell viability, functionality and sub-population
PBMCs can be isolated from healthy donors, who would form a typical donor panel. With access to over 200,000 donors, Lonza has the option to source donors from diseased populations, selected ethnicities or by gender and age in order to test vaccines in a donor population representative of the disease and patient target.
Epibase™ T Cell Assays
Analysis of T cell responses is a frequently used tool to monitor the activation of the immune system. The Epibase™ In Vitro T cell assays take into account not just the molecule, but other factors that may contribute to immunogenicity, such as production contaminants, aggregates and formulation components. Many Epibase™ In Vitro assays can be performed on "whole" molecules or peptides to support the development of vaccines. Additionally, these assays can be used to monitor the immune response during clinical trials.
- Flow cytometry-based detection of cell proliferation and cell surface markers
- Flexible assay formats allow for screening of vaccine candidates with different modes of action
- Whole PBMC assay - direct addition of vaccine candidate to PBMCs
- DC:CD4 Assay - vaccine candidate incubated with dendritic cells then added to autologous CD4+ T cells
- Can be combined with other methods for T cell monitoring
- Cytokine release measured by flow cytometry or ELISPOT assays
- Highly sensitive, enriched ELISPOT assay to identify low frequency memory CD8+ T cell responses
- Large panels of cytokines can also be profiled using high throughput multiplex methods
- Robust, versatile and accurate assays are widely used to monitor the immune response
Immune cells pass through the light source for detection and identification in a flow cytometry instrument.
Epibase™ B Cell Assays
The Epibase™ In Vitro B cell ELISPOT assay is designed to quantitate antibody-secreting B cells. The assays can be used to test for pre-existing humoral immune response, as well as monitor B cell responses to vaccines during clinical trials.
Recall B Cell ELISPOT Assay
- Detection of total and antigen-specific IgA, IgG, IgE, and IgM production
- Blood samples (PBMC) or suspensions of lymphoid tissues can be tested
- Identification and enumeration of total and antigen-specific secreting cells
- Highly sensitive, allowing for analysis at single cell level and quantitation of the number of circulating antigen-specific memory B cells
This assay can be used to detect B cell responses towards natural infections or after vaccination (recall responses), as represented in the graph below.
% of antigen-specific IgG secreting cells per total IgG secreting cells for 12 individual donors.
Adjuvant and Custom Assays
The Epibase™ In Vitro adjuvant assay is a unique offering to vaccine developers. It is used for the compatibility and response assessment of candidate and reference vaccine adjuvants in combination with the immunizing antigen. The assay can be used as pre-selection to or as an alternative to animal studies.
- ELISPOT method used for the detection of total and antigen-specific IgM production at the single cell level
- Quantitative measurement of antibody-secreting cells after in vitro immunization
- Results allow for the determination of the most efficacious adjuvant / antigen combination
- Assay can be performed in combination with T cell assays for analysis of humoral and cellular immune responses
The Epibase™ In Vitro screening assays can also be customized to address additional immunogenicity needs for vaccine development.
- Assays for vaccine potency, cytokine profiling, antigen presenting cell (APC) phenotyping
- Available tools include flow cytometry, ELISPOT, ELISA, and multiplexing methods
- Additional assay development available upon request