Abstract: Provided herein are methods and compositions related to chimeric antigen receptors (CARs) having antigen binding domains derived from an immunoglobulin (Ig) and constant domains derived from a T cell receptor (TCR).

Abstract: Genetically modified mice are provided that express human ? variable (hV?) sequences, including mice that express hV? sequences from an endogenous mouse ? light chain locus, mice that express hV? sequences from an endogenous mouse ? light chain locus, and mice that express hV? sequences from a transgene or an episome wherein the hV? sequence is linked to a mouse constant sequence. Mice are provided that are a source of somatically mutated human ? variable sequences useful for making antigen-binding proteins. Compositions and methods for making antigen-binding proteins that comprise human ? variable sequences, including human antibodies, are provided.

Abstract: Genetically modified mice are provided that express human ? variable (hV?) sequences, including mice that express hV? sequences from an endogenous mouse ? light chain locus, mice that express hV? sequences from an endogenous mouse ? light chain locus, and mice that express hV? sequences from a transgene or an episome wherein the hV? sequence is linked to a mouse constant sequence. Mice are provided that are a source of somatically mutated human ? variable sequences useful for making antigen-binding proteins. Compositions and methods for making antigen-binding proteins that comprise human ? variable sequences, including human antibodies, are provided.

Abstract: Genetically modified non-human animals and methods and compositions for making and using the same are provided, wherein the genetic modification comprises a humanization of an endogenous signal-regulatory protein gene, in particular a humanization of a SIRP? gene. Genetically modified mice are described, including mice that express a human or humanized SIRP? protein from an endogenous SIRP? locus.

Abstract: The invention provides a genetically modified non-human animal that comprises in its genome unrearranged T cell receptor variable gene loci, as well as embryos, cells, and tissues comprising the same. Also provided are constructs for making said genetically modified non-human animal and methods of making the same. Various methods of using the genetically modified non-human animal are also provided.

Abstract: Genetically modified mice are provided that express human ? variable (hV?) sequences, including mice that express hV? sequences from an endogenous mouse ? light chain locus, mice that express hV? sequences from an endogenous mouse ? light chain locus, and mice that express hV? sequences from a transgene or an episome wherein the hV? sequence is linked to a mouse constant sequence. Mice are provided that are a source of somatically mutated human ? variable sequences useful for making antigen-binding proteins. Compositions and methods for making antigen-binding proteins that comprise human ? variable sequences, including human antibodies, are provided.

Abstract: Genetically modified non-human animals and methods and compositions for making and using them are provided, wherein the genetic modification comprises a deletion of the endogenous low affinity Fc?R locus, and wherein the mouse is capable of expressing a functional FcR?-chain. Genetically modified mice are described, including mice that express low affinity human Fc?R genes from the endogenous Fc?R locus, and wherein the mice comprise a functional FcR?-chain. Genetically modified mice that express up to five low affinity human Fc?R genes on accessory cells of the host immune system are provided.

Abstract: Genetically modified mice are provided that express human ? variable (hV?) sequences, including mice that express hV? sequences from an endogenous mouse ? light chain locus, mice that express hV? sequences from an endogenous mouse ? light chain locus, and mice that express hV? sequences from a transgene or an episome wherein the hV? sequence is linked to a mouse constant sequence. Mice are provided that are a source of somatically mutated human ? variable sequences useful for making antigen-binding proteins. Compositions and methods for making antigen-binding proteins that comprise human ? variable sequences, including human antibodies, are provided.

Abstract: Genetically modified mice are provided that express human ? variable (hV?) sequences, including mice that express hV? sequences from an endogenous mouse ? light chain locus, mice that express hV? sequences from an endogenous mouse ? light chain locus, and mice that express hV? sequences from a transgene or an episome wherein the hV? sequence is linked to a mouse constant sequence. Mice are provided that are a source of somatically mutated human ? variable sequences useful for making antigen-binding proteins. Compositions and methods for making antigen-binding proteins that comprise human ? variable sequences, including human antibodies, are provided.

Abstract: Genetically modified mice are provided that express human ? variable (hV?) sequences, including mice that express hV? sequences from an endogenous mouse ? light chain locus, mice that express hV? sequences from an endogenous mouse ? light chain locus, and mice that express hV? sequences from a transgene or an episome wherein the hV? sequence is linked to a mouse constant sequence. Mice are provided that are a source of somatically mutated human ? variable sequences useful for making antigen-binding proteins. Compositions and methods for making antigen-binding proteins that comprise human ? variable sequences, including human antibodies, are provided.

Abstract: Genetically modified mice are provided that express human ? variable (hV?) sequences, including mice that express hV? sequences from an endogenous mouse ? light chain locus, mice that express hV? sequences from an endogenous mouse ? light chain locus, and mice that express hV? sequences from a transgene or an episome wherein the hV? sequence is linked to a mouse constant sequence. Mice are provided that are a source of somatically mutated human ? variable sequences useful for making antigen-binding proteins. Compositions and methods for making antigen-binding proteins that comprise human ? variable sequences, including human antibodies, are provided.

Abstract: Non-human animals, e.g., mammals, e.g., mice or rats, are provided comprising an immunoglobulin heavy chain locus that comprises a rearranged human immunoglobulin heavy chain variable region nucleotide sequence. The rearranged human immunoglobulin heavy chain variable region nucleotide sequence may be operably linked to a heavy or light chain constant region nucleic acid sequence. Also described are genetically modified non-human animals comprising an immunoglobulin light chain locus comprising one or more but less than the wild type number of human immunoglobulin light chain variable region gene segments, which may be operably linked to a light chain constant region nucleic acid sequence. Also provided are methods for obtaining nucleic acid sequences that encode immunoglobulin light chain variable domains capable of binding an antigen in the absence of a heavy chain.

Abstract: The invention provides genetically modified non-human animals that express chimeric human/non-human MHC I and MHC II polypeptides and/or human or humanized ?2 microglobulin polypeptide, as well as embryos, cells, and tissues comprising the same. Also provided are constructs for making said genetically modified animals and methods of making the same. Methods of using the genetically modified animals to study various aspects of human immune system are provided.

Abstract: Genetically modified non-human animals and methods and compositions for making and using the same are provided, wherein the genetic modification comprises a humanization of an endogenous signal-regulatory protein gene, in particular a humanization of a SIRP? gene. Genetically modified mice are described, including mice that express a human or humanized SIRP? protein from an endogenous SIRP? locus.

Abstract: Genetically modified mice are provided that express human ? variable (hV?) sequences, including mice that express hV? sequences from an endogenous mouse ? light chain locus, mice that express hV? sequences from an endogenous mouse ? light chain locus, and mice that express hV? sequences from a transgene or an episome wherein the hV? sequence is linked to a mouse constant sequence. Mice are provided that are a source of somatically mutated human ? variable sequences useful for making antigen-binding proteins. Compositions and methods for making antigen-binding proteins that comprise human ? variable sequences, including human antibodies, are provided.

Abstract: Genetically modified non-human animals and methods and compositions for making and using them are provided, wherein the genetic modification comprises a deletion of the endogenous low affinity Fc?R locus, and wherein the mouse is capable of expressing a functional FcR?-chain. Genetically modified mice are described, including mice that express low affinity human Fc?R genes from the endogenous Fc?R locus, and wherein the mice comprise a functional FcR?-chain. Genetically modified mice that express up to five low affinity human Fc?R genes on accessory cells of the host immune system are provided.

Abstract: Genetically modified mice are provided that express human ? variable (hV?) sequences, including mice that express hV? sequences from an endogenous mouse ? light chain locus, mice that express hV? sequences from an endogenous mouse ? light chain locus, and mice that express hV? sequences from a transgene or an episome wherein the hV? sequence is linked to a mouse constant sequence. Mice are provided that are a source of somatically mutated human ? variable sequences useful for making antigen-binding proteins. Compositions and methods for making antigen-binding proteins that comprise human ? variable sequences, including human antibodies, are provided.

Abstract: Genetically modified non-human animals and methods and compositions for making and using them are provided, wherein the genetic modification comprises (a) a deletion in an immunoglobulin constant region CH1 gene (optionally a deletion in a hinge region) of a heavy chain constant region gene sequence, and (b) replacement of one or all endogenous VH, DH and JH gene segments with at least one unrearranged light chain variable (VL) gene segment and at least one unrearranged light chain joining (JL) gene segment capable of recombining to form a rearranged light chain variable region (VL/JL) nucleotide sequence operably linked to the heavy chain constant region gene sequence comprising a deletion in the CH1 gene and/or insertion of a genetically engineered single rearranged light chain, wherein the mouse is capable of expressing a functional IgM, single domain antigen binding proteins, e.g., VL-single domain binding proteins, and a genetically engineered rearranged light chain.

Abstract: Genetically modified mice and methods and compositions for making and using the same are provided, wherein the genetic modification comprises humanization of an Fc?RI protein.

Abstract: Genetically modified mice are provided that express human ? variable (hV?) sequences, including mice that express hV? sequences from an endogenous mouse ? light chain locus, mice that express hV? sequences from an endogenous mouse ? light chain locus, and mice that express hV? sequences from a transgene or an episome wherein the hV? sequence is linked to a mouse constant sequence. Mice are provided that are a source of somatically mutated human ? variable sequences useful for making antigen-binding proteins. Compositions and methods for making antigen-binding proteins that comprise human ? variable sequences, including human antibodies, are provided.