The present invention relates generally to genetically modified non-human animals and immunodeficient non-human animals characterized by restored complement-dependent cytotoxicity, as well as methods and compositions for assessment of therapeutic antibodies in the genetically modified immunodeficient non-human animals. In specific aspects, the present invention relates to immunodeficient non-obese diabetic (NOD), A/J, A/He, AKR, DBA/2, NZB/BIN, B10.D2/oSn and other mouse strains genetically modified to restore complement-dependent cytotoxicity which is lacking in the unmodified immunodeficient mice. In further specific aspects, the present invention relates to NOD.Cg-Prkdc.sup.scid IL2rg.sup.tm1Wj1/SzJ (NSG), NOD. Cg-Rag1.sup.tm1Mom IL2rg.sup.tm1Wj1/SzJ (NRG) and NOD.Cg-Prkdc.sup.scid IL2rg.sup.tm1Wj1/JicTAc (NOG) mice genetically modified to restore complement-dependent cytotoxicity which is lacking in unmodified NSG, NRG and NOG mice. Methods for assessment of therapeutic antibodies or putative therapeutic antibodies in the genetically modified immunodeficient mice characterized by an intact complement system are provided according to specific aspects of the present invention.

Provided herein are transgenic non-human animals whose genomes comprise two or more human genes selected from CD33, Siglec-5, Siglec-7, Siglec-9, Siglec-11, Siglec-14, and Siglec-16, to methods of screening candidate agents that bind to and/or modulate the function and/or activity of at least one of the human genes in the transgenic non-human animals, and to methods of screening candidate agents to determine their effect on one or more activities and/or functions associated with expression of at least one of the human genes in the transgenic non-human animals Further provided herein are methods of recapitulating a human Siglec immune system in a non-human animal, and methods of generating a non-human animal disease model comprising a human Siglec repertoire.

Genetically modified non-human animals comprising a human or humanized interleukin-7 (IL-7) gene. Cells, embryos, and non-human animals comprising a human or humanized IL-7 gene. Rodents that express human or humanized IL-7 protein. Genetically modified mice that comprise a human or humanized IL-7-encoding gene in their germline, wherein the human or humanized IL-7-encoding gene is under control of endogenous mouse IL-7 regulatory sequences.

The present invention relates inter alia to improvements in the production of chimaeric antibodies in non-human transgenic vertebrates such as mice and rats bearing one or more chimaeric antibody transgenes. In particular, the invention provides for improved non-human vertebrates and cells in which VpreB has been species-matched with the variable region of the chimaeric antibodies. Also, embodiments also provide for species-matching of the entire surrogate light chain for efficient pairing with chimaeric heavy chains during B-cell development in vivo in a non-human transgenic vertebrate setting.

Genetically modified non-human animals comprising a humanized interleukin-15 (IL-15) gene. Cells, embryos, and non-human animals comprising a human IL-15 gene. Rodents that express humanized or human IL-15 protein.

Provided are a transgenic non-human mammal expressing a fusion protein, wherein the fusion protein comprises an subunit of an ATP synthase and two distinct fluorescent proteins as a donor and an acceptor for FRET, one of the fluorescent proteins being placed at an amino terminal moiety of the subunit and the other being placed at a carboxyl terminal moiety of the subunit, and a method of screening for an agent for preventing or treating diseases in a mammal in need thereof, comprising using an above transgenic non-human mammal.

The present invention provides a method of site-directed insertion to H11 locus in pigs by using site-directed cutting system, includes the following steps: 1) identify the targeted sequence targeted by the targeted cutting system in the targeted genome sequence of pigs; 2) design and construct the targeting sequence of the corresponding cutting system according to the targeted site; 3) construction of targeting vector; 4) transfect cells, identify the efficiency of fixed-point insertion by PCR amplification. The invention is dependent on the site-directed cutting system of H11 locus in pigs, to insert the target gene into the target site, in order to solve the problems such as low efficiency of traditional shooting technique, inconvenience design of PCR detection primer, harder to detect. The invention provides a method of site-directed insertion which can stably express the foreign gene at the H11 locus, to build an efficient platform for the production of transgenic pigs.

Methods and compositions using a CRISPR-Cas Type IIIA resulting in RNA gene knockdown and knockout in an animal.

The present disclosure relates to methods for making genetic edits in vitro in a non-human vertebrate cell or embryo at a plurality of target chromosomal DNA sites. Methods for making a non-human animal having multiplex genetic edits at a plurality of target chromosomal DNA sites and making a non-human vertebrate animal chimeric for host cells and donor cells are also considered.

The invention provides a composition comprising an extroembryonic endodermal (XEN) cell and/or an embryonic fibroblast (EP) cell. The invention also provides a method of establishing a XEN cell line or a primary embryonic fibroblast (EF) cell line in vitro, the method comprising culturing a zygote or parthenote from a manual for a time sufficient to produce one or more blastocysts; and culturing the one or more blastocysts on feeder cells in culture medium for a time sufficient to produce one or a plurality of XEN cells and/or one or a plurality of EF cells.