purified protein derivative

initialism: PPD
https://doi.org/10.1351/goldbook.13624
Partially purified derivative of tuberculin used in the Mantoux test for tuberculosis.
Source:
PAC, 2012, 84, 1113. (IUPAC glossary of terms used in immunotoxicology (IUPAC Recommendations 2012)) on page 1237 [Terms] [Paper]