Assertion: immune system's cell | /r/CapableOf | patrol the body
Facets:
value: always
type: TEMPORAL
Source sentences:
text: These cells patrol the body asking themselves whether the tissues that they survey express MHC I molecules.
text: These cells are always patrolling the body and searching for pathogens, but are also reactive to some highly specialised molecular signals generated by other cells, known as cytokines.