An antibody targeted to an antigen is brought into contact with {HEAD ~ a body component} in {TAIL ~ situ} 
in
An antibody targeted to an antigen is brought into contact with { HEAD ~ a body component } in { TAIL ~ situ }
OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH HEAD HEAD HEAD HEAD HEAD HEAD HEAD REL TAIL TAIL TAIL TAIL TAIL