36 results about "Immunoglobulin gene" patented technology

This invention relates to humanized antibodies and antibody preparations produced from transgenic non-human animals. The non-human animals are genetically engineered to contain one or more humanized immunoglobulin loci which are capable of undergoing gene rearrangement and gene conversion in the transgenic non-human animals to produce diversified humanized immunoglobulins. The present invention further relates to novel sequences, recombination vectors and transgenic vectors useful for making these transgenic animals. The humanized antibodies of the present invention have minimal immunogenicity to humans and are appropriate for use in the therapeutic treatment of human subjects.

Dominant negative alleles of human mismatch repair genes can be used to generate hypermutable cells and organisms. By introducing these genes into cells and transgenic animals, new cell lines and animal varieties with novel and useful properties can be prepared more efficiently than by relying on the natural rate of mutation. These methods are useful for generating genetic diversity within immunoglobulin genes directed against an antigen of interest to produce altered antibodies with enhanced biochemical activity. Moreover, these methods are useful for generating antibody-producing cells with increased level of antibody production. The invention also provides methods for increasing the effector function of monoclonal antibodies and monoclonal antibodies with increased effector function.

The invention uses the power of display selection methods to screen libraries of human immunoglobulin genes from nonhuman transgenic animals expressing human immunoglobulins. Such screening produces unlimited numbers of high affinity human antibodies to any target of interest.

Dominant negative alleles of human mismatch repair genes can be used to generate hypermutable cells and organisms. Cells may be selected for expression of activation-induced cytidine deaminase (AID), stimulated to produce AID, or manipulated to express AID for further enhancement of hypermutability. These methods are useful for generating genetic diversity within immunoglobulin genes directed against an antigen of interest to produce altered antibodies with enhanced biochemical activity. Moreover, these methods are useful for generating antibody-producing cells with increased level of antibody production.

The present invention provides ungulate animals, tissue and organs as well as cells and cell lines derived from such animals, tissue and organs, which lack expression of functional endogenous immunoglobulin loci. The present invention also provides ungulate animals, tissue and organs as well as cells and cell lines derived from such animals, tissue and organs, which express xenogenous, such as human, immunoglobulin loci. The present invention further provides ungulate, such as porcine genomic DNA sequence of porcine heavy and light chain immunogobulins. Such animals, tissues, organs and cells can be used in research and medical therapy. In addition, methods are provided to prepare such animals, organs, tissues, and cells.

The invention belongs to the technical field of biotechnology and relates to a human IgE (immunoglobulin E) Fab (fragment ab) against human and a coding gene and application thereof. In the invention, a recombined IgE C3-C4 protein is used for screening a natural human immunoglobulin gene library, and a human antibody Fab of IgE against human is screened from the library through ELISA (enzyme-linked immunosorbent assay) sequencing analysis and the like; extensive expression purification and further identification prove that the antibody Fab of human IgE against human is fully human and without Fc (fragment c), has an effect of inhibiting IgE mediated anaphylaxis without activating complements or causing human immune response or other pathological lesions and can be used for preparing antibody drugs for treating allergic diseases caused by IgE.

The present invention describes transgenic animals with human(ized) immunoglobulin loci and transgenes encoding human(ized) Igα and/or Igβ sequences. Of particular interest are animals with transgenic heavy and light chain immunoglobulin loci capable of producing a diversified human(ized) antibody repertoire that have their endogenous production of Ig and/or endogenous Igα and/or Igβ sequences suppressed. Simultaneous expression of human(ized) immunoglobulin and human(ized) Igα and/or Igβ results in normal B-cell development, affinity maturation and efficient expression of human(ized) antibodies.

The invention provides a nucleic acid. The nucleic acid comprises a human immunoglobulin gene or fragments thereof and is characterized by further comprising a human CD79 gene sequence. By the nucleic acid, the problem of incompatibility between BCR and each of Ig alpha and Ig beta of the human immunoglobulin gene in different species is solved, and secondary modification of a humanized antibody expressed by the nucleic acid is not needed.

The present invention belongs to the field of biotechnology, and relates to a surface antigen 1 (SAG1) of Toxoplasma gondii human antibody Fab fragment, encoded gene and use thereof. According to the invention, the surface antigen 1 (SAG1) of Toxoplasma gondii human antibody Fab fragment is filtered from a base through establishing a Toxoplasma gondii human immunoglobulin, ELISA, diluting the prothrombin time, sequencing analysis, etc. Through expression purifying and authenticating, the human antigen Fab fragment is authenticated to specifically identify the tachyzoite-bradyzoite recombination SAG1 of Toxoplasma gondii and have higher affinity with the tachyzoite-bradyzoite recombination SAG1 of Toxoplasma gondii, for being identified with the specificity of Toxoplasma gondii tachyzoite-bradyzoite. The human antigen Fab fragment of the invention does not contain Fc segment and does not activate the alexin or cause the histopathological damages of human immune response, etc. when the function of restricting the invasion of Toxoplasma gondii to the host cell is exerted. The surface antigen 1 (SAG1) of Toxoplasma gondii human antibody Fab fragment is safe and reliable when applied for the human body. The antigen medicine for treating toxoplasmosis or the antigen targeted medicine can be prepared.

The invention provides a nucleic acid molecule. The nucleic acid molecule comprises an immune globulin gene or a fragment of the immune globulin gene. The nucleic acid molecule is characterized by comprising an IgM gene (IgHCmu) and an IgM transduction element (switch region, Smu), and the Smu and the IgHCmu are host animal sequences. The humanoral antibody is directly acquired, the artificial modification in the later period is reduced, and the druggability of the antibody is improved. The development and the maturation of the transgenic B-cells and the number of the B-cells are completely consistent with those of the normal mouse, thereby being favorable for the differentiation of the B-cells; the specificity and the diversity of the produced antibody are improved; and the efficiency ofscreening the therapeutic antibody is improved.

Methods of monitoring and measuring dynamic adaptive immune cell responses are provided. High-throughput sequencing of T cell receptor and immunoglobulin loci is used to characterize the breadth of an effector cell response to a stimulus, such as a vaccine or infection. Unique responding effector cell clones and abundance thereof can be determined. Additionally, methods for determining the contribution of responding effector cells to the immunological memory compartment are provided.

An artificial antibody library with a super-repertory (10¹¹ or more) is constructed by: using a cDNA library as a template, amplifying a fragment containing the CDR1 and CDR2s regions of the VH or VL region of immunoglobulin gene and a fragment containing the CDR3 region each by the PCR method; integrating the VH library and the VL library, which are little contaiminated with unexpressionable repertory and have high safety, into an nono-expression vector; transferring it into a host; and then shuffling the VH region in the VH library with the VL region in the VL library.

The specification relates to a method for producing a chimeric non-human animal, which comprises preparing a microcell containing a foreign chromosome(s) or a fragment(s) thereof and transferring the foreign chromosome(s) or fragment(s) thereof into a pluripotent cell by fusion with the microcell; a chimeric non-human animal which can be produced by the above method and its progeny; tissues and cells derived therefrom; and a method for using the same. Further, a pluripotent cell containing a foreign chromosome(s) or a fragment(s) thereof, a method for producing the same, and a method for using the same are also provided. Moreover, a pluripotent cell in which at least two endogenous genes are disrupted, and a method for producing the same by homologous recombination are provided.

According to a first aspect of the invention, a method for the generation of a cell line is provided, comprising the steps of (a) providing a plurality of mammalian B cells, wherein each of the plurality of B cells comprises a transgenic genomic DNA sequence encoding a marker protein inserted into an endogenous immunoglobulin locus comprised in said B cell, and wherein the transgenic genomic DNA sequence is amenable to cleavage by a site directed nuclease, particularly Cas9; (b) replacing the transgenic genomic DNA sequence encoding a marker protein with a second transgenic DNA sequence encoding a protein of interest; (c) sorting B cells based on the presence or absence of the marker protein; and (d) collecting B cells in which the marker protein is absent.

The invention provides a method for rearranging immunoglobulin by specifically amplifying a genome. The method comprises the following steps of: cracking mature B cells; amplifying genome genes of the B cells through a primer capable of specifically amplifying a variable region of a heavy chain and/or a light chain of an antibody by using a multiple displacement amplification method, thereby amplifying a sequence of the variable region comprising the heavy chain and/or light chain from the genome relatively and specifically; and performing PCR amplification by using the primer for specifically combining the variable region of the heavy chain and/or the light chain of the antibody by taking reaction solution obtained by multiple displacement amplification as a substrate, thereby obtaining a gene sequence of the variable region of the heavy chain and/or the light chain of the antibody; sequencing an obtained PCR product to determine the gene sequence of the variable region of the heavy chain and/or the light chain of the antibody obtained by PCR amplification. Through the method provided by the invention, rearranged immunoglobulin is obtained and the gene is utilized to product the antibody.