One embodiment of the invention is directed to {HEAD ~ a process} for {TAIL ~ the chemical modification} of organic compounds to form immunogens 
for
One embodiment of the invention is directed to { HEAD ~ a process } for { TAIL ~ the chemical modification } of organic compounds to form immunogens
OTH OTH OTH OTH OTH OTH OTH OTH HEAD HEAD HEAD HEAD HEAD HEAD REL TAIL TAIL TAIL TAIL TAIL TAIL TAIL OTH OTH OTH OTH OTH OTH