A method 8, wherein the washing medium is {HEAD ~ the culture medium} used in {TAIL ~ stage}  
used in
A method 8 , wherein the washing medium is { HEAD ~ the culture medium } used in { TAIL ~ stage }
OTH OTH OTH OTH OTH OTH OTH OTH OTH HEAD HEAD HEAD HEAD HEAD HEAD HEAD REL REL TAIL TAIL TAIL TAIL TAIL OTH