The invention discloses methods for the generation of chimaeric human—non-human antibodies and chimaeric antibody chains, antibodies and antibody chains so produced, and derivatives thereof including fully humanised antibodies; compositions comprising said antibodies, antibody chains and derivatives, as well as cells, non-human mammals and vectors, suitable for use in said methods.

Non-human animal genomes, non-human animal cells, and non-human animals comprising a humanized TTR locus and methods of using such non-human animal genomes, non-human animal cells, and non-human animals are provided. Non-human animal cells or non-human animals comprising a humanized TTR locus express a human transthyretin protein or a chimeric transthyretin protein, fragments of which are from human transthyretin. Methods are provided for using such non-human animals comprising a humanized TTR locus to assess in vivo efficacy of human-TTR-targeting reagents such as nuclease agents designed to target human TTR. Methods are also provided for making such non-human animals comprising a humanized TTR locus.

Provided is a bispecific recombinant protein, comprising a high affinity tumor-targeting arm and a low affinity fusion protein blocking the interaction of CD47 with SIRPα. The antibody corresponding to the high affinity tumor-targeting arm does not bind to CD47, and its binding affinity to the target antigen on the tumor cell is at least 6 times as great as the binding affinity of monomer fusion protein homodimer, corresponding to the low affinity fusion protein blocking the interaction of CD47 with SIRPα, to a CD47 on the tumor cell, wherein the low affinity fusion protein blocking the interaction of CD47 with SIRPα comprises a SIRPα extracellular truncation. Also provided are nucleic acid molecules encoding recombinant proteins and the use of the recombinant proteins and nucleic acid molecules in the manufacture of a medicament for treating tumors.

A biological system for generating and preserving a repository of personalized, humanized transplantable cells, tissues, and organs for transplantation, wherein the biological system is biologically active and metabolically active, the biological system having genetically reprogrammed cells, tissues, and organs in a non-human animal for transplantation into a human recipient, wherein the non-human animal does not present one or more surface glycan epitopes and specific sequences from the wild-type swine's SLA is replaced with a synthetic nucleotides based on a human captured reference sequence from a human recipient's HLA.

Non-human animal genomes, non-human animal cells, and non-human animals comprising a humanized KLKB1 locus and methods of making and using such non-human animal genomes, non-human animal cells, and non-human animals are provided. Non-human animal cells or non-human animals comprising a humanized KLKB1 locus express a human plasma kallikrein protein or a chimeric plasma kallikrein protein, fragments of which are from human plasma kallikrein. Methods are provided for using such non-human animals comprising a humanized KLKB1 locus to assess in vivo efficacy of human-KLKB 1-targeting reagents such as nuclease agents designed to target human KLKB1.

The present disclosure provides transgenic nematode systems for assessing function of heterologous genes, their variants and drug discovery. The transgenic nematodes contain a heterologous gene that is inserted via homologous recombination at the native locus replacing and removing the nematode ortholog, wherein expression of the heterologous gene rescues function of the removed nematode ortholog and a transgenic control animal is provided. The heterologous gene may be further modified to provide a variant, such as a human clinical variant, whereby a transgenic test animal is provided. Those transgenic test animals are used in methods to assess function of the heterologous variant and drug screens to find therapeutic candidates reversing deviant activity back to wildtype.

The present disclosure relates to genetically modified non-human animals (e.g., genetically-modified mice or rodents) that express a hACE2 and/or hTMPRRS2 under control of the mouse promoter and the genetically modified non-human animal does not express native ACE2 and/or hTMPRRS2. The present disclosure also relates to methods of generating the genetically-modified animals (e.g., genetically modified mice or rodents), and methods of using the genetically modified non-human animals (e.g., genetically modified mice or rodents) described herein.

A transgenic non-human animal is provided. In certain embodiments, the animal comprises a genome comprising an immunoglobulin heavy chain locus comprising: a) a transcribed gene encoding a fusion protein comprising, from N-terminus to C-terminus: i. a scaffold comprising a first binding domain; and ii. a heavy chain constant region operably linked to the scaffold; wherein the scaffold is capable of specifically binding to a target in the absence of additional polypeptides; and b) a plurality of pseudogenes that are operably linked to the transcribed gene and that donate, by gene conversion, nucleotide sequence to the part of the transcribed gene that encodes the binding domain.

The present disclosure provides, among other things, genetically modified non-human animals whose germline genome comprises an engineered endogenous immunoglobulin κ light chain locus comprising a single rearranged human immunoglobulin λ light chain variable region operably linked to a non-human Cλ gene segment, where the single rearranged human immunoglobulin λ light chain variable region comprises a human Vλ gene segment and a human Jλ gene segment. All immunoglobulin λ light chains expressed by B cells of the genetically modified non-human animal include human immunoglobulin λ light chain variable domains expressed from the single rearranged human immunoglobulin λ light chain variable region or a somatically hypermutated version thereof. Such animals, tissues from such animals, and cells from such animals represent an effective platform for producing antibodies, e.g., bispecific antibodies.

This disclosure relates to genetically modified animals and cells with humanized light chain immunoglobulin locus and/or humanized heavy chain immunoglobulin locus. In one aspect, the endogenous light chain immunoglobulin locus comprises a limit number of human IGKV genes and human IGKJ genes.