Nexia Biotechnologies, Inc.

Mcgill University

Flockton Analytical Management Inc.

Jeffrey D Turner

Costas N Karatzas

Anthoula Lazaris-Karatzas

Constantinos Karatzas

Hung Huynh

Carol Keefer

Disclosed is a method for the recombinant production of biofilaments, such as spider silk or insect fibroins, using transgenic animals which secrete the biofilaments in their milk and/or urine, and transgenic cells which secrete the biofilaments into culture media. Such a method is useful for producing large quantities of biofilament material. Also disclosed is a nucleic acid molecule for generating such transgenic animals.

Production of biofilaments in transgenic animals

The invention features a method which includes the following steps: (a) introducing a transgene into a zygote of a dwarf goat, (b) transplanting the zygote into a pseudopregnant non-dwarf goat, and (c) allowing the zygote to develop to term. In another aspect the invention features a method which includes the following steps: (a) introducing a transgene into an embryo of a dwarf goat, (b) transplanting the embryo into a pseudopregnant non-dwarf goat, and (c) allowing the embryo to develop to term.

Method for development of transgenic dwarf goats

Disclosed is a method for expressing a heterologous gene in the mammary gland of a ruminant mammal. The invention is useful for producing a heterologous protein(s) in the milk of the mammal, for producing a heterologous enzyme(s) which is tethered to the mammary epithelial cell membrane and which can act on a component of the milk of the mammal, and for providing an antisense oligonucleotide(s) or ribozyme(s) which inhibits expression of a gene to a mammary epithelial cell. The method involves infusing a liquid complex including a genetic construct into a ductal tree of the mammal. The liquid complex can be infused before the mammal reaches sexual maturity and after the mammal develops a functional streak canal. Alternatively, a liquid complex that is free of live retroviruses can be infused. If desired, the infused genetic construct can be treated with a polycationic compound and/or a lipid to improve the efficiency with which it is taken up by an epithelial cell of the mammary gland.

Direct gene transfer into the ruminant mammary gland

The present invention relates to a ruminant immortalized mammary epithelial cell line which has normal physiological responses in that it produces milk constituents which comprises .alpha. and .beta.-casein and lactose. There is provided, using the cell line of the present invention a method in vitro studying lactation. There is provided a method of in vitro screening for gene expression of DNA constructs for transgenic ruminant animals. The cell line can be further used in a method for expressing foreign genes. One cell line of the present invention has been deposited at the ATCC under the accession number CRL10274.

Ruminant immortalized mammary epithelial cell lines

A calibration standard for calibrating machines which count the somatic cells in a milk sample, comprises an aqueous dispersion of microbeads bearing a fluorescent dye, a suspending agent, and an electrolyte; the dye has an excitation wavelength below 580 nm and a fluorescence emission wavelength in the range of 550 to 660 nm, with the excitation wavelength being at least 10 nm below the emission wavelength; the microbeads are present in a predetermined number per unit volume of dispersion; typically the standard contains 1.times.10.sup.5 to 9.times.10.sup.5 beads/ml.

Shelf-stable milk calibration standards

The present invention relates to a bovine immortalized mammary epithelial cell line which has normal physiological responses in that it produces milk constituents which comprises .alpha.- and .beta.-casein and lactose. There is provided, using the cell line of the present invention a method of `in vitro` studying lactation. There is provided a method of `in vitro` screening for gene expression of DNA constructs for transgenic cows, since the cell line of the present invention is a bovine one. The cell line can be further used in a method for indefinitely expressing foreign genes. The cell line of the present invention has been deposited at the ATCC under the accession number CRL 10274.

Growing community of inventors

Hudson, Canada

Jeffrey D Turner