To develop a gene therapy strategy for treating bovine mastitis, a new mammary-specific vector containing human lysozyme (hLYZ) cDNA and kanamycin resistance gene was constructed for intramammary expression and clinic...To develop a gene therapy strategy for treating bovine mastitis, a new mammary-specific vector containing human lysozyme (hLYZ) cDNA and kanamycin resistance gene was constructed for intramammary expression and clinical studies. After one time acupuncture or intracisternal infusion of healthy cows with 400 μg of the p215C3LYZ vector, over 2.0 μg/ml of rhLYZ could be detected by enzymatic assay for about 3 weeks in the milk samples. Western blotting showed that rhLYZ secreted into milk samples from the vector-injected cows had molecular weight similar to that of the natural hLYZ in human colostrums. Twenty days after the primary injection, the quarters were re-injected with the same vector by quarter acupuncture and even higher concentrations of rhLYZ could be detected. Indirect competitive ELISA of milk samples showed that the vector injection did not induce detectable humoral immune response against hLYZ. Clinical studies showed that twice acupuncture of quarters with the p215C3LYZ vector had overt therapeutic effect on clinical and subclinical mastitis previously treated with antibiotics, including disappearance of clinical symptoms and relatively high microbiological cure rates. These data provide a solid rationale for using the vector to develop gene therapy for treating bovine mastitis.展开更多
THE mammary gland bioreactor system of lactating animal, established by germ-linemicroinjection and embryo transplantation, has been one of the most exciting projects in thefield of biotechnology. However, this system...THE mammary gland bioreactor system of lactating animal, established by germ-linemicroinjection and embryo transplantation, has been one of the most exciting projects in thefield of biotechnology. However, this system is costly, laborious and tim-cosuming. In 1994,Johanna et al. reported that secretion of a foreign protein, human growth hormone (hGH),in milk had been achieved after direct introduction of the cDNA into the mammary gland ofgoats by replication-defective retroviral vector. In that work, the in vivo expression of展开更多
基金Project (Nos. BJ2001315 and BE2004611) supported by the De-partment of Science and Technology of Jiangsu Province, China
文摘To develop a gene therapy strategy for treating bovine mastitis, a new mammary-specific vector containing human lysozyme (hLYZ) cDNA and kanamycin resistance gene was constructed for intramammary expression and clinical studies. After one time acupuncture or intracisternal infusion of healthy cows with 400 μg of the p215C3LYZ vector, over 2.0 μg/ml of rhLYZ could be detected by enzymatic assay for about 3 weeks in the milk samples. Western blotting showed that rhLYZ secreted into milk samples from the vector-injected cows had molecular weight similar to that of the natural hLYZ in human colostrums. Twenty days after the primary injection, the quarters were re-injected with the same vector by quarter acupuncture and even higher concentrations of rhLYZ could be detected. Indirect competitive ELISA of milk samples showed that the vector injection did not induce detectable humoral immune response against hLYZ. Clinical studies showed that twice acupuncture of quarters with the p215C3LYZ vector had overt therapeutic effect on clinical and subclinical mastitis previously treated with antibiotics, including disappearance of clinical symptoms and relatively high microbiological cure rates. These data provide a solid rationale for using the vector to develop gene therapy for treating bovine mastitis.
文摘THE mammary gland bioreactor system of lactating animal, established by germ-linemicroinjection and embryo transplantation, has been one of the most exciting projects in thefield of biotechnology. However, this system is costly, laborious and tim-cosuming. In 1994,Johanna et al. reported that secretion of a foreign protein, human growth hormone (hGH),in milk had been achieved after direct introduction of the cDNA into the mammary gland ofgoats by replication-defective retroviral vector. In that work, the in vivo expression of