Abstract

The binding of monoclonal antibodies (MAbs) of predetermined specificity to growth hormone (GH) can result in significant enhancement of the biological activity of the hormone in vivo. The topographic region on GH associated with the enhancement phenomenon has been localised to two proximate sites on adjacent loop regions by extensive peptide synthesis (sequences: 35-53 and 134-154). The application of these observations of GH and (ii) increased production parameters following administration of particular antibodies. The latter aspect has now been demonstrated in a number of animal models by the passive vaccination of animals with purified anti-peptide antisera or monoclonal antibodies. Production parameters affected in such experiments include growth rate, fat metabolism, diabetogenic activity and lactation in ewes. At the present time, it has been shown that peptide sequence 134-154 will elicit up to 80% high titre, immuno- positive responders in sheep. Monitoring the growth rate and other production parameters of lambs vaccinated with sequence 134-154 indicates improved growth and total protein characteristics. These observations, in conjunction with the development of methodologies for effective autoimmunization of animals, may provide a basis for the design of peptide vaccines to improve animals, may provide a basis for the design of peptide vaccines to improve animal production.

JH, Niezen, TN Barry, J Hodgson, PR Wilson, and CW Holmes

Proceedings of the New Zealand Society of Animal Production, Volume 51, , 185-188, 1991