Production of recombinant Human factor Viii in tHe milk of transgenic rabbits

the stability of milk production, quality and content of recombinant human factor viii (rhFviii) in transgenic rabbits was determined. transgenic rabbits carrying the mouse whey acid protein promoter (mWaP) and human factor viii gene (hFviii) were born after mating of transgenic and non-transgenic rabbits. PCr analysis of samples from F4 generation showed that the transgene was transmitted. Milk production, obtained at � th, 5th, 2�th and 3�th day of the first lactation by weight-suckle-weight method,� showed no significant difference between transgenic and non-transgenic does�� �o significant difference between transgenic and non-transgenic rabbit milk composition was also found�� ELISA test confirmed rhFVIII at the level of 3 – 12 μg/ml�� Milk sample from non-transgenic rabbit was hFviii negative. in conclusion, the stabilty of hFviii transgene transmission and production of rhFVIII was confirmed in F4 generation of transgenic rabbits,� with lower efficiency than in F1,� F2 and F3 generations,� but without reduction in milk production. key words: rhFviii, transgenic, rabbit, milk production, correspondence: e-mail: [email protected] iSSn 335-3686 introduction the mammary gland of farm animals is probably the most promising target tissue because it produces large amounts of protein in a temperature-regulated fluid that may be collected daily in a non-invasive fashion. transgenic animals used as bioreactors to produce human recombinant proteins represent a new horizon in animal husbandry, but are often followed by low viability of newborn animals. repercussions of that can also be irregular secretion and alteration of milk composition. Milk is usually the sole source of nourishment of young mammals, therefore offspring growth and development depends on milk. rabbit milk yield may be affected by breed of doe (Lukafahr et al., 983), nutrition (Chrastinova et al., 997), number of kids suckling and their age of weaning and pregnancy during lactation (Lukafahr et al., 983). intensive recombinant human protein production by mammary gland of transgenic rabbit necessitates the knowledge of the lactation curve and quality (composition) of milk as a possible effect of transgenesis on milk yield (Chrenek et al., 2��7a). Lactating rabbit female can produce 7�-22�g of milk per day and yield up to �kg of milk per year under semiautomatic hygienic milking conditions�� Some other criteria which influences selection of the species for transgenesis are reproductive