Transgenically produced non-secreted proteins

Abstract

The invention provides a method of making and secreting a non-secreted protein. The method includes expressing the protein from a nucleic acid construct which includes: (a) a mammary epithelial specific promoter; (b) a milk protein specific signal sequence which can direct the secretion of a protein; (c) optionally, a sequence which encodes a sufficient portion of the amino terminal coding region of a secreted protein to allow secretion in the milk of a transgenic mammal, of the non-secreted protein; and (d) a sequence which encodes a non-secreted protein, wherein elements (a), (b), optionally (c), and (d) are preferably operatively linked in the order recited. Both glutamic acid decarboxylase (GAD) and myelin basic protein (MBP), which are cytoplasmic proteins, have been produced by the methods of the present invention. The invention also provides methods for treating diabetes and multiple sclerosis using proteins produced by the methods of the present invention.

Description

[0001] This application claims the benefit of a previously filed Provisional Application No. 60 / 038,998, filed Feb. 25, 1997, which is hereby incorporated by reference.FIELD OF THE INVENTION [0002] This invention relates to the production and secretion of proteins which are not ordinarily secreted. BACKGROUND OF THE INVENTION [0003] A growing number of recombinant proteins are being developed for therapeutic and diagnostic applications. However, many of these proteins may be difficult or expensive to produce in a functional form and / or in the required quantities using conventional methods. Conventional methods involve inserting the gene responsible for the production of a particular protein into host cells such as bacteria, yeast, or mammalian cells, e.g., COS cells, and then growing the cells in culture media. The cultured cells then synthesize the desired protein. Traditional bacteria or yeast systems may be unable to produce many complex proteins in a functional form. While mamma...

AI Technical Summary

Benefits of technology

The invention features a method for making and secreting a protein that is not normally secreted in a mammal. This is done by introducing a nucleic acid construct into the mammal that includes a promoter, a signal sequence, and a sequence that encodes a sufficient portion of the amino terminal coding region of a secreted protein. The nucleic acid construct is preferably introduced into a transgenic mammal, such as a sheep, mouse, pig, cow, or goat. The method can be used to produce non-secreted proteins in the milk of a transgenic mammal. The non-secreted proteins can be fused to other sequences, such as a signal sequence or a sequence that encodes a sufficient portion of the amino terminal coding region of a secreted protein. The invention provides a way to produce and secrete non-secreted proteins in mammals, which can be useful in various applications.

Problems solved by technology

However, many of these proteins may be difficult or expensive to produce in a functional form and / or in the required quantities using conventional methods.

Traditional bacteria or yeast systems may be unable to produce many complex proteins in a functional form.

While mammalian cells can reproduce complex proteins, they are generally difficult and expensive to grow, and often produce only mg / L quantities of protein.

In addition, non-secreted proteins are relatively difficult to purify from procaryotic or mammalian cells as they are not secreted into the culture medium.

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