title: Double trans-chromosomic mice: maintenance of two individual human chromosome fragments containing Ig heavy and kappa loci and expression of fully human antibodies.
abstract: The use of a human chromosome or its fragment as a vector for animal transgenesis may facilitate functional studies of large human genomic regions. We describe here the generation and analysis of double trans-chromosomic (Tc) mice harboring two individual human chromosome fragments (hCFs). Two transmittable hCFs, one containing the Ig heavy chain locus (IgH, approximately 1.5 Mb) and the other the kappa light chain locus (Igkappa, approximately 2 Mb), were introduced into a mouse strain whose endogenous IgH and Igkappa loci were inactivated. In the resultant double-Tc/double-knockout mice, substantial proportion of the somatic cells retained both hCFs, and the rescue in the defect of Ig production was shown by high level expression of human Ig heavy and kappa chains in the absence of mouse heavy and kappa chains. In addition, serum expression profiles of four human Ig gamma subclasses resembled those seen in humans. They mounted an antigen-specific human antibody response upon immunization with human serum albumin, and human serum albumin-specific human monoclonal antibodies with various isotypes were obtained from them. These results represent a generation of mice with "humanized" loci by using the transmittable hCFs, which suggest that the Tc technology may allow for the humanization of over megabase-sized, complex loci in mice or other animals. Such animals may be useful not only for studying in vivo functions of the human genome but also for obtaining various therapeutic products.
authors.affiliation: Pharmaceutical Research Laboratory, Kirin Brewery Co., Ltd., Miyahara-cho 3, Takasaki-shi, Gunma 370-1295, Japan.
authors.forename: K
authors.initials: K
authors.lastname: Tomizuka
authors.forename: T
authors.initials: T
authors.lastname: Shinohara
authors.forename: H
authors.initials: H
authors.lastname: Yoshida
authors.forename: H
authors.initials: H
authors.lastname: Uejima
authors.forename: A
authors.initials: A
authors.lastname: Ohguma
authors.forename: S
authors.initials: S
authors.lastname: Tanaka
authors.forename: K
authors.initials: K
authors.lastname: Sato
authors.forename: M
authors.initials: M
authors.lastname: Oshimura
authors.forename: I
authors.initials: I
authors.lastname: Ishida
mesh_terms: D000818:Animals; D000906:Antibodies / Q000097:blood; D000911:Antibodies, Monoclonal / Q000097:blood / Q000276:immunology; D002877:Chromosomes, Human / Q000235:genetics*; D003433:Crosses, Genetic; D004797:Enzyme-Linked Immunosorbent Assay; D005260:Female; D005347:Fibroblasts / Q000166:cytology / Q000378:metabolism; D006801:Humans; D006822:Hybrid Cells; D007143:Immunoglobulin Heavy Chains / Q000235:genetics; D007145:Immunoglobulin kappa-Chains / Q000235:genetics; D017404:In Situ Hybridization, Fluorescence; D008297:Male; D051379:Mice; D018345:Mice, Knockout; D008822:Mice, Transgenic / Q000235:genetics*; D012709:Serum Albumin / Q000276:immunology
chemical_list: D000906:Antibodies; D000911:Antibodies, Monoclonal; D007143:Immunoglobulin Heavy Chains; D007145:Immunoglobulin kappa-Chains; D012709:Serum Albumin