Plucked scalp hair is an ideal surrogate for measuring a direct response following treatment. Highly vascularised, the hair follicle can rapidly respond to novel therapeutic agent exposure. Given this vascularisation, the epithelial nature and rapid rate of proliferation, the cells in the hair bulb and outer root sheath are a highly relevant surrogate tissue for biomarker analysis.
Gene expression can be of particular advantage where the target or pathway is unknown. Profiles can be obtained from plucked hairs using Epistem's proprietary gene expression technologies. Small amounts of RNA are extracted from the hair bulb and gene expression levels are determined by either microarray or qRT-PCR analysis. Gene expression can be used to correlate the effect of therapeutic agent on target tissue with hairs sampled from preclinical models. Expression in plucked hair can also be correlated with known biomarkers in matched serum and plasma samples.
Epistem's highly sensitive, GCLP compliant platform can be applied to the analysis of hair collected during clinical studies either for market approval or post marketing for patient stratification. Epistem has conducted GCLP accredited clinical studies in support of drug development pipelines for a number of major pharmaceutical customers. Hair is an ideal surrogate tissue as it is easy to sample, has good patient compliance and few ethical issues.
Epistem can source healthy donors for scalp hair sampling and determine intra- and inter-donor variability to ensure subsequent clinical studies are sufficiently powered. Confirmation of optimal storage duration for antigen stability can also be determined and used to inform clinical trial protocol.
Plucked Hair Sampling
Hair sampling is simple. Sampling kits, including a collection guide, are provided by Epistem and further training in hair sampling is available to ensure optimal quality of tissue. Hairs are rapidly fixed at the collection site and shipped to Epistem for analysis.