Assertion: guinea pig | /r/HasProperty | employed in study
Facets:
value: on the production of antibodies
type: TRANSITIVE-OBJECT
value: often
type: TEMPORAL
Source sentences:
text: In the past, they were widely used to standardize vaccines and antiviral agents; they were also often employed in studies on the production of antibodies in response to extreme allergic reactions, or anaphylaxis.