Intramammary expression and therapeutic effect of a human lysozyme-expressing vector for treating bovine mastitis.

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 microg of the p215C3LYZ vector, over 2.0 microg/ml of rhLYZ could be detected by enzymatic assay for about 3 weeks in the milk samples.