Antibody producing non-human mammals

Abstract

Described are transgenic, non-human animals comprising a nucleic acid encoding an immunoglobulin light chain, whereby the immunoglobulin light chain is human, human-like, or humanized. The nucleic acid is provided with a means that renders it resistant to DNA rearrangements and/or somatic hypermutations. In one embodiment, the nucleic acid comprises an expression cassette for the expression of a desired molecule in cells during a certain stage of development in cells developing into mature B cells. Further provided is methods for producing an immunoglobulin from the transgenic, non-human animal.

Description

CROSS-REFERENCE TO RELATED APPLICATION[0001]This application claims the benefit, under 35 U.S.C. §119(e), to U.S. Provisional Patent Application Ser. No. 61 / 133,274, filed Jun. 27, 2008, for “Antibody Producing Non-Human Mammals,” the entire contents of which are hereby incorporated hereby by this reference.TECHNICAL FIELD[0002]The invention relates to the production and use of non-human animals capable of producing antibodies or derivatives thereof, which are expressed from at least partially exogenous nucleic acids (transgenes). Transgenes to produce such transgenic animals and methods to produce such heterologous antibodies; methods and vectors for producing such transgenic animals are disclosed.BACKGROUND OF THE INVENTION[0003]B cells mediate humoral immunity by producing specific antibodies. The basic structural subunit of an antibody (Ab) is an immunoglobulin (Ig) molecule. Ig molecules consist of a complex of two identical heavy (H) and two identical light (L) polypeptide cha...

AI Technical Summary

Benefits of technology

[0031]The means for prevention of silencing comprise STabilizing Anti-Repression-sequences (STAR®-sequences) and Matrix Attachment Regions (MARs). A STAR sequence is a nucleic acid sequence that comprises a capacity to influence transcription of genes in cis. Typically, although not necessarily, a STAR sequence does not code by itself for a functional protein element. In one embodiment one STAR element is used. Preferably, however, more than one STAR element is used. In a particularly preferred embodiment an expression cassette described herein is provided with two STAR sequences; one STAR sequence at the 5′ side of the coding sequence of the immunoglobulin gene and one STAR sequence at the 3′ side of the coding sequence of the immunoglobulin gene. MARs are DNA sequences that are involved in anchoring DNA / chromatin to the nuclear matrix and they have been described in both mammalian and plant species. MARs possess a number of features that facilitate the opening and maintenance of euchromatin. MARs can increase transgene expression and limit position-effects.

[0032]Expression from the cassette should only occur during a certain period in the development of a cell, in particular a developing B cell, more in particular a B cell in a transgenic non-human animal, in particular a mouse. In this particular case the developmental period is chosen such that the expression of the gene from the cassette (typically a light- or heavy chain-like polypeptide) does not significantly interfere with the normal differentiation and / or maturation of the cell and when applicable, allows for pairing of the polypeptide chain produced with its counterpart.

Problems solved by technology

One of the major impediments facing the development of in vivo applications for mAbs in humans is the intrinsic immunogenicity of non-human Igs.

Patients respond to therapeutic doses of mouse mAbs by making antibodies against the mouse Ig sequences (Human Anti Mouse Antibodies; HAMA), causing acute toxicity, alter their biodistribution and accelerate clearance, thus reducing the efficacy of subsequent administrations (Mirick et al.

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