Of {TAIL ~ particular relevance} is {HEAD ~ the marked increase} in the expression of genes associated with the production of gamma interferon, a potent antiviral agent and regulator of the immune response 
Of { TAIL ~ particular relevance } is { HEAD ~ the marked increase } in the expression of genes associated with the production of gamma interferon , a potent antiviral agent and regulator of the immune response
REL TAIL TAIL TAIL TAIL TAIL TAIL REL HEAD HEAD HEAD HEAD HEAD HEAD HEAD OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH