A TUNEL assay method is claimed and described. The method comprises loading slides having mounted tissue samples into a primary stainer and testing tissue samples for apoptosis using a stainer. In one embodiment, the method includes using a stainer having a plurality of reservoirs. A reagent reservoir is loaded with anti-conjugate antibody reporter. A slide tray of the stainer is loaded with a slide having a tissue sample. The stainer adds anti-conjugate antibody reporter to the sample for a duration.