693 results about "CD4 antigen" patented technology

The present invention relates to a genetically engineered, CD19-specific chimeric T cell receptor and to immune cells expressing the chimeric receptor The present invention also relates to the use of such cells for cellular immunotherapy of CD9+ malignancies and for abrogating any untoward B cell function. The chimeric receptor is a single chain scFvFc:ζ receptor where scFvFc designates the extracellular domain, scFv designates the VH and VL chains of a single chain monoclonal antibody to CD19, Fc represents at least part of a constant region of an IgG1, and ζ represents the intracellular signaling domain of the zeta chain of human CD3. The extracellular domain scFvFc and the intracellular domain ζ are linked by a transmembrane domain such as the transmembrane domain of CD4. In one aspect, the chimeric receptor comprises amino acids 23-634 of SEQ I DNO:2. The present invention further relates to a method of making a redirected T cell expressing a chimeric T cell receptor by electroporation using naked DNA encoding the receptor.

Disclosed and claimed is a new insect cell line, Sf900+, ATCC CRL-12579. The insect cell line was established from Lepidoptera, Noctuidae, Spodoptera frugiperda Sf-9 (ATCC CRL-1711) through multiple rounds of limiting dilution and selection in a serum-free insect medium supplemented with added human insulin. The insect cell line is useful in BEVS or as an adjuvant and has many characteristics and advantages. Also disclosed and claimed are recombinant proteins from recombinant baculovirus expression in insect cells such as Sf900+ cells, for instance, HA, NA, EPO, CD4, CEA, and thrombospondin.

The enumeration of cells in fluids by flow cytometry is widely used across many disciplines such as assessment of leukocyte subsets in different bodily fluids or of bacterial contamination in environmental samples, food products and bodily fluids. For many applications the cost, size and complexity of the instruments prevents wider use, for example, CD4 analysis in HIV monitoring in resource-poor countries. The novel device, methods and algorithms disclosed herein largely overcome these limitations. Briefly, all cells in a biological sample are fluorescently labeled, but only the target cells are also magnetically labeled. The labeled sample, in a chamber or cuvet, is placed between two wedge-shaped magnets to selectively move the magnetically labeled cells to the observation surface of the cuvet. An LED illuminates the cells and a CCD camera captures the images of the fluorescent light emitted by the target cells. Image analysis performed with a novel algorithm provides a count of the cells on the surface that can be related to the target cell concentration of the original sample. The compact cytometer system provides a rugged, affordable and easy-to-use technique, which can be used in remote locations.

The invention provides antibodies specific for HIV env, including monoclonal antibodies and related hybridomas. The antibodies block CD4 / g120 binding and reduce reverse transcriptase activity in vitro.

Disclosed is a method of directing a cellular immune response against an HIV-infected cell in a mammal involving administering to the mammal an effective amount of therapeutic cells which express a membrane-bound, proteinaceous chimeric receptor comprising (a) an extracellular portion which includes a fragment of CD4 which is capable of specifically recognizing and binding the HIV-infected cell but which does not mediate HIV infection and (b) an intracellular portion which is capable of signalling the therapeutic cell to destroy the receptor-bound HIV-infected cell. Also disclosed is a second method of treating HIV in a mammal involving administering to the mammal an effective amount of therapeutic cells expressing a membrane-bound, proteinaceous chimeric receptor comprising an extracellular portion which includes a fragment of CD4 which is capable of specifically recognizing and binding the HIV-infected cell but which does not mediate HIV infection. Also disclosed are cells which express the chimeric receptors and DNA and vectors encoding the chimeric receptors.

A family of chimeric antigen receptors (CARs) containing a CD123 specific scFv was developed to target different epitopes on CD123. In some embodiments, such a CD123 chimeric antigen receptor (CD123CAR) gene includes an anti-CD123 scFv region fused in frame to a modified IgG4 hinge region comprising an S228P substitution, an L235E substitution, and optionally an N297Q substitution; a costimulatory signaling domain; and a T cell receptor (TCR) zeta chain signaling domain. When expressed in healthy donor T cells (CD4 / CD8), the CD123CARs redirect T cell specificity and mediated potent effector activity against CD123+ cell lines as well as primary AML patient samples. Further, T cells obtained from patients with active AML can be modified to express CD123CAR genes and are able to lyse autologous AML blasts in vitro. Finally, a single dose of 5.0×106 CAR123 T cells results in significantly delayed leukemic progression in mice. These results suggest that CD123CAR-transduced T cells may be used as an immunotherapy for the treatment of high risk AML.

The invention provides antibodies that specifically bind to human CD134. Anti-human CD134 antibodies specifically bind to the extracellular domain of human CD134, including non-OX40 ligand (OX40L) binding domains on human CD134, which is expressed on e.g. activated human conventional effector CD4 and / or CD8 T lymphocytes (Teffs) and on activated human suppressive regulatory CD4 T lymphocytes (Tregs). Humanized anti-human CD134 antibodies are useful (e.g. to empower Teffs anti-cancer effector function and / or to inhibit Tregs suppressive function) for cancer treatment.

The present invention relates to methods and compositions designed for the treatment, management, or prevention of cancer, particularly metastatic cancer and cancers of T cell origin, and hyperproliferative diseases involving EphA2-expressing cells. The methods of the invention entail the use of a Listeria-based EphA2 vaccine. The invention also provides pharmaceutical compositions comprising one or more Listeria-based vaccines of the invention either alone or in combination with one or more other agents useful for cancer therapy. In certain aspects of the invention, the methods entail eliciting both CD4+ and CD8+ T-cell responses against EphA2 and / or EphA2-expressing cells.

The invention relates to transgenic non-human animals capable of producing high affinity human sequence antibodies. The invention is also directed to human sequence antibodies specific for human antigens, such as, human CD4. The invention also is directed to methods for producing human sequence antibodies.

The present invention is a recombinant vector encoding and expressing at least three or more costimulatory molecules. The recombinant vector may additionally contain a gene encoding one or more target antigens or immunological epitope thereof. The synergistic effect of these costimulatory molecules on the enhanced activation of T cells is demonstrated. The degree of T-cell activation using recombinant vectors containing genes encoding three costimulatory molecules was far greater than the sum of recombinant vector constructs containing one costimulatory molecule and greater than the use of two costimulatory molecules. Results employing the triple costimulatory vectors were most dramatic under conditions of either low levels of first signal or low stimulator to T-cell ratios. This phenomenon was observed with both isolated CD4+ and CD8+ T cells. The recombinant vectors of the present invention are useful as immunogenes and vaccines against cancer and pathogenic micro-organisms, and in providing host cells, including dendritic cells and splenocytes with enhanced antigen-presenting functions.

The invention provides antibodies that specifically bind to human CD134. Invention anti-human CD134 antibodies specifically bind to the extracellular domain of human CD134, including non-OX40 ligand (OX40L) binding domains on human CD134, which is expressed on e.g. activated human conventional effector CD4 and / or CD8 T lymphocytes (Teffs) and on activated human suppressive regulatory CD4 T lymphocytes (Tregs). Invention anti-human CD134 antibodies are useful (e.g. to empower Teffs anti-cancer effector function and / or to inhibit Tregs suppressive function) for cancer treatment.

The present invention provides methods and compositions to confer and / or augment immune responses mediated by cellular immunotherapy, such as by adoptively transferring genetically modified tumor specific CD8+ T cells in the presence of tumor-specific, subset specific genetically modified CD4+ T cells, wherein the CD4+ T cells confer and / or augment a CD8+ T cells ability to sustain anti-tumor reactivity and increase and / or maximize tumor-specific proliferation of the tumor-specific CD8+ T cells of interest. Pharmaceutical formulations produced by the method, and methods of using the same, are also described.

The present invention is a recombinant vector encoding and expressing at least three or more costimulatory molecules. The recombinant vector may additionally contain a gene encoding one or more target antigens or immunological epitope thereof. The synergistic effect of them costimulatory molecules on the enhanced activation of T cells is demonstrated. The degree of T-cell activation using recombinant vectors containing genes encoding three costimulatory molecules was far greater than the sum of recombinant vector constructs containing one costimulatory molecule and greater that the use of two costimulatory molecules. Results employing the triple costimulatory vectors were most dramatic under conditions of either low levels of first signal or low stimulator to T-cell ratios. This phenomenon was observed with both isolated CD4+and CD8+T cells. The recombinant vectors of the present invention are useful as immunogenes and vaccines against cancer and pathogenic micro-organisms, and in providing host cells, including dendritic cells and splenocytes with enhanced and antigen-presenting functions.

The invention relates to polyepitope carrier proteins that comprise at least five CD4+ T cell epitopes, for conjugation to capsular polysaccharides. The carrier proteins are use useful as components of vaccines that can elicit a T-cell dependent immune response. These vaccines arm particularly useful to confer protection against infection from encapsulated bacteria in infants between the ages of 3 months and about 2 years.

A mutant Fab fragment of the 13B8.2 anti-CD4 antibody that binds a CD4 molecule and includes a mutation of at least one residue in a position situated in the VH variable domain of the heavy chain and / or in a position situated in the Vκ variable domain of the light chain.

The present invention relates to chimeric transmembrane immunoreceptors, named “zetakines,” comprised of an extracellular domain comprising a soluble receptor ligand linked to a support region capable of tethering the extracellular domain to a cell surface, a transmembrane region and an intracellular signalling domain. Zetakines, when expressed on the surface of T lymphocytes, direct T cell activity to those specific cells expressing a receptor for which the soluble receptor ligand is specific. Zetakine chimeric immunoreceptors represent a novel extension of antibody-based immunoreceptors for redirecting the antigen specificity of T cells, with application to treatment of a variety of cancers, particularly via the autocrin / paracrine cytokine systems utilized by human malignancy. In a preferred embodiment is a glioma-specific immunoreceptor comprising the extracellular targetting domain of the IL-13Rα2-specific IL-13 mutant IL-13(E13Y) linked to the Fc region of IgG, the transmembrane domain of human CD4, and the human CD3 zeta chain.

The present invention provides nucleic acids, vectors, host cells, methods and compositions to confer and / or augment immune responses mediated by cellular immunotherapy, such as by adoptively transferring CD8+ central memory T cells or combinations of central memory T cells with CD4+ T cells that are genetically modified to express a chimeric receptor. In embodiments the genetically modified host cell comprises a nucleic acid comprising a polynucleotide coding for a ligand binding domain, a polynucleotide comprising a customized spacer region, a polynucleotide comprising a transmembrane domain, and a polynucleotide comprising an intracellular signaling domain. It has been surprisingly found that the length of the spacer region can affects the ability of chimeric receptor modified T cells to recognize target cells in vitro and affects in vivo efficacy of the chimeric receptor modified T cells. Pharmaceutical formulations produced by the method, and methods of using the same, are also described.

The enumeration of cells in fluids by flow cytometry is widely used across many disciplines such as assessment of leukocyte subsets in different bodily fluids or of bacterial contamination in environmental samples, food products and bodily fluids. For many applications the cost, size and complexity of the instruments prevents wider use, for example, CD4 analysis in HIV monitoring in resource-poor countries. The novel device, methods and system disclosed herein largely overcome these limitations. The system includes a simple system for CD4 and CD8 counting in point-of-care HIV staging within resource poor countries. Unlike previous approaches, no sample preparation is required with the sample added directly to a chip containing dried reagents by capillary flow. A large area image cytometer consisting of an LED module is used to excite the fluorochromes PerCP and APC labeled targets and a monochrome CCD camera with a combination of two macro lenses captures images of 40 mm2 of blood (approximately 1 microliter). CD4 and CD8-T-lymphocyte counts correlate well with those obtained by flow cytometry. The cytometer system described in the present invention provides an affordable and easy-to-use technique for use in remote locations.

The enumeration of cells in fluids by flow cytometry is widely used across many disciplines such as assessment of leukocyte subsets in different bodily fluids or of bacterial contamination in environmental samples, food products and bodily fluids. For many applications the cost, size and complexity of the instruments prevents wider use, for example, CD4 analysis in HIV monitoring in resource-poor countries. The novel device, methods and algorithms disclosed herein largely overcome these limitations. Briefly, all cells in a biological sample are fluorescently labeled, but only the target cells are also magnetically labeled. In addition, non-magnetically labeled cells are imaged for viability in a modified slide configuration. The labeled sample, in a chamber or cuvet, is placed between two wedge-shaped magnets to selectively move the magnetically labeled cells to the observation surface of the cuvet. An LED illuminates the cells and a CCD camera captures the images of the fluorescent light emitted by the target cells. Image analysis performed with a novel algorithm provides a count of the cells on the surface that can be related to the target cell concentration of the original sample. The compact cytometer system provides a rugged, affordable and easy-to-use technique, which can be used in remote locations.

Regulatory T cells (Treg) limit autoimmunity but can also attenuate the magnitude of anti-pathogen and anti-tumor immunity. Understanding the mechanism of Treg function and therapeutic manipulation of Treg in vivo requires identification of Treg selective receptors. A comparative analysis of gene expression arrays from antigen specific CD4+ T cells differentiating to either an effector / memory or a regulatory phenotype revealed Treg selective expression of LAG-3 (CD223), a CD4-related molecule that binds MHC class II. LAG-3 expression on CD4+ T cells correlates with the cells' in vitro suppressor activity, and ectopic expression of LAG-3 on CD4 T cells confers suppressor activity on the T cells. Antibodies to LAG-3 inhibit suppression both in vitro and in vivo. LAG-3 marks regulatory T cell populations and contributes to their suppressor activity.

The present invention concerns methods and compositions for treatment of HIV infection in a subject, utilizing a DNL complex comprising at least one anti-HIV therapeutic agent, attached to an antibody, antibody fragment or PEG. In a preferred embodiment, the antibody or fragment binds to an antigen selected from gp120, gp41, CD4 and CCR5. In a more preferred embodiment the antibody is P4 / D10 or 2G12, although other anti-HIV antibodies are known and may be utilized. In a most preferred embodiment, the anti-HIV therapeutic agent is a fusion inhibitor, such as T20, T61, T651, T1249, T2635, CP32M or T-1444, although other anti-HIV therapeutic agents are known and may be utilized. The DNL complex may be administered alone or may be co-administered with one or more additional anti-HIV therapeutic agents.

The invention provides genetically modified non-human animals that express chimeric human / non-human T cell co-receptor polypeptides (e.g., CD4, CD8α, CD8β), 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.

The present invention provides methods for generating mammalian T cell populations comprising antigen-specific CD4+CD25+ regulatory T cells from freshly isolated CD4+CD25− T cells. The method comprises selecting CD4+CD25− T cells from a sample obtained from a mammalian subject; determining the MHC Class II type of the subject; inducing the generation of antigen-specific regulatory T cells by contacting the isolated CD4+CD25− T cells in a culture vessel with an induction agent for a time period sufficient to generate antigen-specific CD4+CD25+ regulatory T cells; and selecting the CD4+CD25+ antigen-specific regulatory T cells by sorting the cells in the induction culture with a selection agent comprising at least one artificial multimeric MHC Class II / peptide complex that corresponds to the MHC Class II type of the subject.

An analysis method for identifying and counting particles expressing a specific antigenic marker is proposed. One example (but not exclusive) is CD4+ T-lymphocyte analysis in blood. The method comprises obtaining a sample comprising particles in suspension, labeling the particles expressing the specific marker with an impedance label, and measuring the labeled sample using a dual frequency system to discriminate at least the labeled particles expressing the specific marker. The method allows an accurate count of particles e.g. the number CD4+ T-lymphocytes in a blood flow. A corresponding device is also provided.

This invention provides an antibody capable of specifically inhibiting the fusion of an HIV-1 envelope glycoprotein+ cell with an appropriate CD4+ cell without cross reacting with the HIV-1 envelope glycoprotein or CD4 and capable of inhibiting infection by one or more strains of HIV-1. This antibody is then used to identify a molecule which is important for HIV infection. Different uses of the antibody and the molecule are described.

The present invention relates to a product and process for suppressing an immune response using a T lymphocyte veto molecule capable of blocking cell surface molecules responsible for T cell activation. Disclosed is a CD4 or CD2 molecule, associated with an immunoglobulin molecule capable of binding to a major histocompatibility antigen. Also disclosed is a method to produce a T lymphocyte veto molecule, a therapeutic composition comprising a T lymphocyte veto molecule and methods to use T lymphocyte veto molecules in therapeutic processes requiring suppression of an immune response.

The present invention relates to chimeric transmembrane immunoreceptors, named “zetakines,” comprised of an extracellular domain comprising a soluble receptor ligand linked to a support region capable of tethering the extracellular domain to a cell surface, a transmembrane region and an intracellular signalling domain. Zetakines, when expressed on the surface of T lymphocytes, direct T cell activity to those specific cells expressing a receptor for which the soluble receptor ligand is specific. Zetakine chimeric immunoreceptors represent a novel extension of antibody-based immunoreceptors for redirecting the antigen specificity of T cells, with application to treatment of a variety of cancers, particularly via the autocrin / paracrine cytokine systems utilized by human maligancy. In a preferred embodiment is a glioma-specific immunoreceptor comprising the extracellular targetting domain of the IL-13Rα2-specific IL-13 mutant IL-13(E13Y) linked to the Fc region of IgG, the transmembrane domain of human CD4, and the human CD3 zeta chain.

The present invention provides a pharmaceutical composition for treating an autoimmune disease comprising a pharmaceutically acceptable carrier and an agent capable of activating CD4+CD25+ regulatory T cells, wherein the composition is to be administered to a subject in a dose of the agent from 0.2 mg to 30 mg.