Direct Peptide Reactivity Assay
Commonly used acronym: DPRA
Scope of the method
- Human health
- Basic Research
- Regulatory use - Routine production
- In chemico
- Animal derived cells / tissues / organs
- Molecular initiating event
- Skin Sensitisation
- in vitro
- molecular initiating event
The DPRA is an in chemico method which quantifies the remaining concentration of cysteine- or lysine-containing peptide following 24 hours incubation with the test chemical at 25 +/-2,5ºC. The synthetic peptides contain phenylalanine to aid in the detection. Relative peptide concentration is measured by highperformance liquid chromatography (HPLC) with gradient elution and UV detection at 220 nm. Cysteineand lysine peptide percent depletion values are then calculated and used in a prediction model (see paragraph 29) which allows assigning the test chemical to one of four reactivity classes used to support the discrimination between sensitisers and non-sensitisers.
- History of use
- Internally validated
- Validated by an external party (e.g. OECD, EURL ECVAM,…)
Pros, cons & Future potential
- Validated methodology (EURL ECVAM) ;
- AOP based ;
- High throughput ;
- Low cost ;
- In chemico.
The test method described in this Test Guideline is an in chemico method that does not encompass a metabolic system.
The methodology behind AOP and MIE can be applied to other toxicological endpoints.
References, associated documents and other information
OECD, TG 442C, OECD GUIDELINE FOR THE TESTING OF CHEMICALS, In Chemico Skin Sensitisation: Direct Peptide Reactivity Assay (DPRA)
Contact personbart Desmedt
Chemical and physical health risks
Medicines and health products