title: Large-scale production of functional human lysozyme from marker-free transgenic cloned cows.
abstract: Human lysozyme is an important natural non-specific immune protein that is highly expressed in breast milk and participates in the immune response of infants against bacterial and viral infections. Considering the medicinal value and market demand for human lysozyme, an animal model for large-scale production of recombinant human lysozyme (rhLZ) is needed. In this study, we generated transgenic cloned cows with the marker-free vector pBAC-hLF-hLZ, which was shown to efficiently express rhLZ in cow milk. Seven transgenic cloned cows, identified by polymerase chain reaction, Southern blot, and western blot analyses, produced rhLZ in milk at concentrations of up to 3149.19 ± 24.80 mg/L. The purified rhLZ had a similar molecular weight and enzymatic activity as wild-type human lysozyme possessed the same C-terminal and N-terminal amino acid sequences. The preliminary results from the milk yield and milk compositions from a naturally lactating transgenic cloned cow 0906 were also tested. These results provide a solid foundation for the large-scale production of rhLZ in the future.
authors.affiliation: The State Key Laboratory for Agro-biotechnology, China Agricultural University, Beijing, China.|Shanghai Institute of Medical Genetics, Shanghai Children's Hospital, Shanghai, China.
authors.forename: Dan
authors.initials: D
authors.lastname: Lu
authors.affiliation: The State Key Laboratory for Agro-biotechnology, China Agricultural University, Beijing, China.
authors.forename: Shen
authors.initials: S
authors.lastname: Liu
authors.affiliation: The State Key Laboratory for Agro-biotechnology, China Agricultural University, Beijing, China.
authors.forename: Fangrong
authors.initials: F
authors.lastname: Ding
authors.affiliation: The State Key Laboratory for Agro-biotechnology, China Agricultural University, Beijing, China.
authors.forename: Haiping
authors.initials: H
authors.lastname: Wang
authors.affiliation: The State Key Laboratory for Agro-biotechnology, China Agricultural University, Beijing, China.
authors.forename: Jing
authors.initials: J
authors.lastname: Li
authors.affiliation: The State Key Laboratory for Agro-biotechnology, China Agricultural University, Beijing, China.
authors.forename: Ling
authors.initials: L
authors.lastname: Li
authors.affiliation: The State Key Laboratory for Agro-biotechnology, China Agricultural University, Beijing, China.
authors.forename: Yunping
authors.initials: Y
authors.lastname: Dai
authors.affiliation: The State Key Laboratory for Agro-biotechnology, China Agricultural University, Beijing, China.
authors.forename: Ning
authors.initials: N
authors.lastname: Li
mesh_terms: D000818:Animals; D030801:Animals, Genetically Modified / Q000235:genetics* / Q000378:metabolism; D002417:Cattle; D019976:Cloning, Organism; D005285:Fermentation; D006801:Humans; D008892:Milk / Q000737:chemistry / Q000201:enzymology*; D009113:Muramidase / Q000096:biosynthesis* / Q000235:genetics; D011994:Recombinant Proteins / Q000096:biosynthesis* / Q000235:genetics
chemical_list: D011994:Recombinant Proteins; D009113:Muramidase