Histologically defined biomarkers in toxicology.

Histopathology is the gold standard when defining toxicological effects, but it is invasive, time consuming and expensive. Using biomarkers linked to distinct, defined cell types and tissues may provide a direct link to histopathology without its drawbacks and it also provides increased sensitivity and specificity. Furthermore, as histological testing is often impractical in human subjects, using biomarkers with a known histological distribution may fill the need of localising toxic injury to distinct organs or tissues. This paper discusses how, by using biomarkers with a known cellular origin (histologically defined biomarkers), toxic effects may be found earlier and at lower doses of compound, leading to potential savings in drug development.