Thus, {HEAD ~ cells} embedded in {TAIL ~ this enhanced hydrogel matrix} substantially escape host immune destruction 
embedded in
Thus , { HEAD ~ cells } embedded in { TAIL ~ this enhanced hydrogel matrix } substantially escape host immune destruction
OTH OTH HEAD HEAD HEAD HEAD HEAD REL REL TAIL TAIL TAIL TAIL TAIL TAIL TAIL TAIL OTH OTH OTH OTH OTH