Investigations of ‘transfer factor’ activity in the transfer of immunity to Trichostrongylus axei infections in sheep

Investigations of transfer factor activity in resistance toTrichostrongylus colubriformisinfections in guinea-pigs

“…Some time therefore elapsed between Experiment 4 and Experiment 5 in which the level of larval challenge was increased to ensure adequate parasite burdens and the experiment designed to consider the possible effects of storage on transfer factor activity. As non-dialysed transfer factor has previously successfully transferred resistance in the sheep/T axei system (Ross & HALLIDAY, 1979b) the results of the present investigation appear to indicate that storage of prepared transfer factor, or storage of tissues before preparation, or the preparation procedures as such, may lead to loss of activity. Storage deterioration may partially explain a similar variability in transfer factor activity which has been observed with the T. axei/sheep and Haemonchus comortus/sheep (MACKENZIE, HUNTER & Ross, personal communication) systems although in the latter systems the transfer factor preparations were months rather than years old.…”

“…Resistance was successfully transferred by a variety of routes and these results were broadly similar to those previously observed with T. axei infections in sheep (Ross & HALLIDAY, 1979a and b). In the T. colubriformis/guinea-pig system transfer of resistance by transfer factor administration is being achieved in an outbred line of guinea-pigs and between sheep and guineapigs and in the T. axei/sheep system transfer of resistance by transfer factor has been achieved both within and between differing donor and recipient breeds of sheep (Ross & HALLIDAY, 1979b). These results differ from previous investigations of the transfer of resistance with whole leucocytes in which a successful transfer is recorded within inbred guinea-pig lines to challenge infection with 7!…”

“…Transfer factor prepared from sheep infected with T. colubriformis: A yearling Blackface ram was infected orally with 10000 T. colubriformis third-stage larvae and six months later 350 ml of blood was subsequently collected from the jugular vein into a flask containing K 2 EDTA. The leucocytes were recovered, lysed, dialysed, lyophilized and reconstituted as previously described (Ross & HALLIDAY, 1979b) with a recovery of approximately 2x 10 9 leucocyte equivalents. The dialysate was reconstituted in 5 ml distilled water and approximately 2 x 10 8 leucocyte equivalents were given to each guinea-pig in 0-5 ml amounts.…”