TFRC and infection: Ga also binds to lactoferrin, a protein released by neutrophils at sites of inflammation and which has higher iron affinity than transferrin.108 Coupled with the high expression of TfR1, trafficking via transferrin is believed to be the basis for the use of [67Ga]Ga–citrate for imaging infection and inflammation, particularly for identifying infection sites in fever of unknown origin (FUO) patients.