Immunohistochemistry was used to demonstrate the presence of three proteins (actin, osteocalcin and alkaline phosphatase) within the same ethylenediaminetetraacetic acid (EDTA) decalcified and paraffin embedded bone tissue section. EDTA chelated calcium ions, causing endogenous alkaline phosphatase (ALP) to be inactivated. By ablating endogenous ALP activity through chelation, we were able to use an ALP based detection system before reactivation of the endogenous enzyme with magnesium chloride. After reactivation, endogenous ALP itself was demonstrated immunohistochemically. (The J Histotechnol 15:93, 1992).
- Alkaline phosphatase