challenge

in immunology
https://doi.org/10.1351/goldbook.12997
Induction or evaluation of an immune response in an organism by administration of a specific antigen to which it has been sensitized.
Source:
PAC, 2012, 84, 1113. (IUPAC glossary of terms used in immunotoxicology (IUPAC Recommendations 2012)) on page 1142 [Terms] [Paper]