The establishment of two transgenic goat lines for mammary gland hG-CSF expression

Abstract

The production of recombinant human granulocyte-colony stimulating factor (hG-CSF) for therapeutic purposes relies on its expression in selected clones of transfected mammalian cells. Alternatively, this protein can be produced by targeted secretion in the milk of transgenic goats. Thus, the aim of this study was to produce founder transgenic goats expressing hG-CSF and to propagate a transgenic production herd. After DNA microinjection of in vivo-produced pronuclear embryos was performed, two founders were obtained (one male and one female, named 10 M and 12 F, respectively). The mean level of hG-CSF secreted in the milk from the 12 F goat, which was measured during a period of induced lactation, was 620.92±179.93μg/ml. In addition, the recombinant protein presented in vitro biological activity on differentiation of human umbilical stem cells to neutrophil granulocyte series. A total of nine kids (six from 10 M and three from 12 F) that carried the hG-CSF transgene were generated by outbreeding of the founders. In summary, we produced two transgenic goats with a stably integrated hG-CSF gene that were capable of secreting recombinant hG-CSF from the lactating mammary gland without causing any harm to the animals’ health. Additionally, the founders proved to be fertile and capable of transmitting the hG-CSF gene to first generation progeny of each line. Additional investigations of the phenotypic and genotypic characteristics of the 10 M and 12 F lines are warranted.