106 results about "MHC class II" patented technology

The present invention relates to utrons, RNA molecules which contain promoter regulatory motif(s) and DNA analogs thereof and DNA molecules that can be transcribed to produce the foregoing. In particular, the invention provides gene promoter suppressing nucleic acids which suppress transcription from a promoter of interest. In a preferred embodiment, the invention provides the TSU gene, nucleotide sequences of the TSU gene and RNA, as well as fragments, homologs and derivatives thereof. Methods of isolating TSU genes are also provided. Therapeutic and diagnostic methods and pharmaceutical compositions are also provided. In particular, the invention relates to methods for cell replacement therapy, gene therapy or organ transplantation wherein TSU nucleic acids suppress MHC class I and II gene expression, thus preventing immuno-rejection of non-autologous cells or organs. The invention also provides methods for treatment of diseases or disorders by suppression of MHC class I, MHC class II, ICAM-1, B7-1, B7-2, and / or Fc gamma R expression by provision of TSU function.

This invention provides a process for producing major histocompatibility antigen class II protein (hereinafter referred to as "MHC class II" for short) which occurs on the surfaces of antigen-presenting cells and the like, and MHC class II-bound materials in which MHC class II, alpha and / or beta subunit of MHC class II, or a part thereof is bound to a carrier such as beads, fibers and hollow fibers via covalent bond, as well as a module for removing superantigen using the same. This invention also provides a method for detecting or quantifying superantigens using MHC class II or a part thereof having an affinity to the superantigens, as well as an assay kit therefor.

Disclosed are compositions and methods for producing fusion proteins with reduced immunogenicity. Fusion proteins of the invention include a junction region having an amino acid change that reduces the ability of a junctional epitope to bind to MHC Class II, thereby reducing its interaction with a T-cell receptor. Methods of the invention involve analyzing, changing, or modifying one or more amino acids in the junction region of a fusion protein in order to identify a T-cell epitope and reduce its ability to interact with a T cell receptor. Compositions and methods of the invention are useful in therapy.

Specificity in immune responses is in part controlled by the selective interaction of T cell receptors with their cognate ligands, peptide / MHC molecules. The discriminating nature of this interaction makes these molecules, in soluble form, good candidates for selectively regulating immune responses. Attempts to exploit soluble analogs of these proteins has been hampered by the intrinsic low avidity of these molecules for their ligands. To increase the avidity of soluble analogs for their cognates to biologically relevant levels, divalent peptide / MHC complexes or T cell receptors (superdimers) were constructed. Using a recombinant DNA strategy, DNA encoding either the MHC class II / peptide or TCR heterodimers was ligated to DNA coding for murine Ig heavy and light chains. These constructs were subsequently expressed in a baculovirus expression system. Enzyme-linked immunosorbant assays (ELISA) specific for the Ig and polymorphic determinants of either the TCR or MHC fraction of the molecule indicated that infected insect cells secreted approximately 1 .mu.g / ml of soluble, conformnationally intact chimeric superdimers. SDS PAGE gel analysis of purified protein showed that expected molecular weight species. The results of flow cytometry demonstrated that the TCR and class II chimeras bound specifically with high avidity to cells bearing their cognate receptors. These superdimers will be useful for studying TCR / MHC interactions, lymphocyte tracking, identifying new antigens, and have possible uses as specific regulators of immune responses.

Disclosed are synthetic nanocarrier methods, and related compositions, comprising administering immunosuppressants and MHC Class I-restricted and / or MHC Class II-restricted epitopes that can generate tolerogenic immune responses (e.g., antigen-specific T effector cell deletion).

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.

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.

Disclosed are compositions and methods for producing fusion proteins with reduced immunogenicity. Fusion proteins of the invention include a junction region having an amino acid change that reduces the ability of a junctional epitope to bind to MHC Class II, thereby reducing its interaction with a T-cell receptor. Methods of the invention involve analyzing, changing, or modifying one or more amino acids in the junction region of a fusion protein in order to identify a T-cell epitope and reduce its ability to interact with a T cell receptor. Compositions and methods of the invention are useful in therapy.

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.

The present invention provides of using multimeric MHC class II / peptide complexes. In one aspect, methods provided for identifying MHC class II-restricted immune epitopes of a predetermined polypeptide antigen. Methods for identifying an immunostimulatory epitope for a predetermined polypeptide antigen are provided. In a related aspect, methods for screening a therapeutic polypeptide agent for an MHC class II epitope are provided. In other aspects, methods for modulating T cells and for determining or monitoring an MHC class II-restricted immune status of a patient are also provided.

Disclosed are synthetic nanocarrier methods, and related compositions, comprising B cell and / or MHC Class II-restricted epitopes and immunosuppressants in order to generate tolerogenic immune responses, such as the generation of antigen-specific regulatory B cells.

The present invention provides, in particular embodiments, for modified recombinant T cell receptor (TCR) ligands (RTLs) comprising a MHC class I or MHC class II component. The modified RTLs have redesigned surface features that preclude or reduce aggregation, wherein the modified molecules retain the ability to bind Ag-peptides, target antigen-specific T cells, inhibit T cell proliferation in an Ag-specific manner and have utility to treat, inter alia, autoimmune disease and other conditions mediated by antigen-specific T cells in vivo.

The invention provides isolated primate cells preferably human cells that comprise a genetically engineered disruption in a human leukocyte antigen (HLA) class II-related gene, which results in deficiency in MHC class II expression and function. This invention also provides isolated cells further comprising a genetically engineered disruption in a beta-2 microglobulin (B2M) gene, which results in HLA class I / class II deficiency. Also provided are the method of using the cells for transplantation and treating a disease condition.

Disclosed is a method for increasing vaccine potency whereby a subject's immune system is first primed with an Ii-Key hybrid peptide construct before the subject subsequently receives a vaccine for a pathogen of interest. The vaccine may be comprised of a protein or portion thereof that is encoded by the genome of the pathogen. The vaccine may also be a DNA vaccine comprised of DNA encoding a protein of the pathogen. The Ii-Key hybrid peptide construct includes the LRMK residues of Ii-Key protein and an MHC Class II epitope of the protein or portion thereof which is used in the vaccine. The Ii-Key construct may be administered in the form of a nucleic acid construct encoding the Ii-Key hybrid peptide. Priming with Ii-Key peptides enhances the immunogenicity of rHA protein and HA and HIV DNA vaccines. Methods are described relating to the use of Ii-Key hybrid constructs in vaccine protocols wherein the pathogen is HIV or Influenza A, including H5N1. Methods and compositions are described wherein the MHC Class II epitope of the Ii-Key hybrid is hemagglutinin encoded by Influenza A or the Gag protein encoded by HIV.

Disclosed are induced tolerogenic dendritic cells (itDCs) produced by combining itDCs with externally loadable MHC Class I-restricted epitopes, as well as related compositions and methods.

Two-domain MHC polypeptides useful for manipulation of antigen-specific T-cells are disclosed. These polypeptides include MHC class II-based molecules that comprise covalently linked β1 and α1 domains, and MHC class I-based molecules that comprise covalently linked α1 and α2 domains. These polypeptides may also include covalently linked antigenic determinants, toxic moieties, and / or detectable labels. The disclosed polypeptides can be used to target antigen-specific T-cells, and are useful, among other things, to detect and purify antigen-specific T-cells, to induce or activate T-cells, and to treat conditions mediated by antigen-specific T-cells.

The invention provides a quiescent stem cell having the capacity to differentiate into ectoderm, mesoderm and endoderm, and which does not express cell surface markers including MHC class I, MHC class II, CD44, CD45, CD13, CD34, CD49c, CD73, CD105 CD90, CD66A, CD66E, CXCR4, CD133 or an SSEA. The invention further provides a proliferative stem cell, which expresses genes including Oct-4, Nanog, Sox2, GDF3, P16INK4, BMI, Notch, HDAC4, TERT, Rex-1, TWIST, KLF-4 and Stella but does not express cell surface markers including MHC class I, MHC class II, CD44, CD45, CD13, CD34, CD49c, CD73, CD105, CD90, CD66A, CD66E, CXCR4, CD133 or an SSEA. The cells of the invention can be isolated from adult mammals, have embryonic cell characteristics, and can form embryoid bodies. Methods for obtaining the stem cells, as well as methods of treating diseases and differentiated the stem cells, are also provided.

The present invention relates to methods of causing MHC-class II or CD40 mediated immunomodulation, immunosuppression and anti-inflammatory action, in a subject suffering from or susceptible of suffering from a condition involving inappropriate immune response, which comprises administering to the subject at least one statin in an amount effective to modulate MHC class II or CD40 expression in the subject.

The present invention relates to peptides, nucleic acids, and cells for use in the immunotherapy of cancer. The present invention furthermore relates to survivin-derived tumor-associated cytotoxic T cell (CTL) peptide epitopes, alone or in combination with other tumor-associated peptides that serve as active pharmaceutical ingredients of vaccine compositions that stimulate anti-tumor immune responses. The present invention specifically relates to three novel peptide sequences and variants thereof derived from HLA class I and class II molecules of human tumor cells that can be used in vaccine compositions for eliciting anti-tumor immune responses.

The invention provides a quiescent stem cell having the capacity to differentiate into ectoderm, mesoderm and endoderm, and which does not express cell surface markers including MHC class I, MHC class II, CD44, CD45, CD13, CD34, CD49c, CD73, CD105 and CD90. The invention further provides a proliferative stem cell, which expresses genes including Oct-4, Nanog, Sox2, GDF3, P16INK4, BMI, Notch, HDAC4, TERT, Rex-1 and TWIST but does not express cell surface markers including MHC class I, MHC class II, CD44, CD45, CD13, CD34, CD49c, CD73, CD105 and CD90. The cells of the invention can be isolated from adult mammals, have embryonic cell characteristics, and can form embryoid bodies. Methods for obtaining the stem cells, as well as methods of treating diseases and differentiated the stem cells, are also provided.

It is intended to provide a transgenic nonhuman mammal well representing the pathologic conditions of human rheumatoid arthritis. A transgenic nonhuman mammal is obtained by transferring a foreign DNA, wherein a DNA selected from the group consisting of an MHC class II transcriptional activator gene, the activity domain of an MHC class II transcriptional activator gene and a variant of an MHC class II transcriptional activator gene is provided under the control of a type II collagen promoter, into a cell at the early stage of development.

The present invention provides molecules, preferably designed immunoglubulins, suitable for use as an anti-idiotype vaccine to CEA positive tumours. The molecules induce both an MHC class I and MHC class II mediated immune response to the CEA bearing tumour cells for an efficient and sustained host anti-tumour response. The present invention provides modified versions of anti-idiotype anti-CEA antibodies, preferably mouse antibody 708, with improved vaccination properties. The modifications are related to the introduction of sequences tracts deriving from e.g. CEA, CD55 antigen and CEA cancer-specific MHC epitopes into the variable regions of said antibody molecules.

The invention provides an isolated or purified T-cell receptor (TCR) having antigenic specificity for MHC Class II-restricted MAGE-A3. The invention further provides related polypeptides and proteins, as well as related nucleic acids, recombinant expression vectors, host cells, and populations of cells. Further provided by the invention are antibodies, or an antigen binding portion thereof, and pharmaceutical compositions relating to the TCRs of the invention. Methods of detecting the presence of cancer in a host and methods of treating or preventing cancer in a mammal are further provided by the invention.

Methods for treating or preventing hyperproliferating diseases, e.g., cancer, are described. A method may comprise administering to a subject in need thereof a therapeutically effective amount of a nucleic acid encoding an MHC class I and / or II activator and optionally a nucleic acid encoding an antigen.

The invention belongs to the technical field of medicine and relates to a use of cyclic dinucleotide cGAMP and its derivatives as immunologic adjuvants. The study result shows that cGAMP and its derivatives can stimulate the innate immunity of the human body, are effective immunomodulators, can significantly improve the immune response and antibody titer, can stimulate expression of immature dendritic cell surface histocompatible complex MHCII antigens and an enhancement molecule CD80 / CD86, can increase secretion of cytokines and chemokines (such as interleukin and interferon), and can activate and enhance dendritic cells and T cells. Therefore, cGAMP and its derivatives can be used as potential immunologic adjuvants and play an important role in preparation of vaccines.

The present invention provides, in particular embodiments, for modified recombinant T cell receptor (TCR) ligands (RTLs) comprising a MHC class I or MHC class II component. The modified RTLs have redesigned surface features that preclude or reduce aggregation, wherein the modified molecules retain the ability to bind Ag-peptides, target antigen-specific T cells, inhibit T cell proliferation in an Ag-specific manner and have utility to treat, inter alia, autoimmune disease and other conditions mediated by antigen-specific T cells in vivo.

A novel vaccine that can induce sufficiently high cell-mediated immunity is disclosed. The vaccine of the present invention contains, as an effective component, a polypeptide comprising a tandem repeat structure in which an MHC class I epitope region derived from an antigen protein and a spacer sequence are linked to each other alternately and repeatedly at least three times, or a recombinant vector which comprises a polynucleotide encoding said polypeptide and is capable of expressing said polypeptide in vivo. The spacer sequence is, for example, a sequence generated as an amino acid sequence inevitably encoded by a single base sequence which is designed such that the MHC class I epitope region derived from the antigen protein, an MHC class II epitope region derived from the antigen protein, and at least one higher-order-structure-stabilizing region are encoded by different reading frames in said single base sequence.

The invention provides means and methods for inhibiting T-cell mediated rejection of a xenotransplanted organ by blocking the delivery of co-stimulatory signal 2 (the B7 / CD28 interaction) in order to prevent the activation of xenoreactive T-cells in the recipient. In a first aspect, co-stimulation is prevented by administration to the organ recipient of a soluble form of CTLA-4 from the xenogeneic donor organism. This preferentially binds B7 on the xenograft and blocks the interaction between B7 on the xenogeneic donor cells and CD28 on recipient T-cells. In a second aspect, co-stimulation is antagonized by expressing a ligand for CTLA-4 on the xenogeneic donor cells. This ligand binds to CTLA-4 on activated T-cells of the recipient and antagonizes signal 2. In a third aspect, co-stimulation is prevented by expressing recipient organism MHC class II on the surface of the cells of the xenogeneic donor organ. The donor cells are thus able to present xenoantigens to a recipient T-cell in the context of self-MHC class II. If the donor cells do not express B7, or if B7 is blocked, the xenoreactive recipient T-cell becomes anergic.

Disclosed herein are the nucleotide sequences, deduced amino acid sequences as well as methods and compositions necessary to elicit immune responses against chronic Hepatitis B infections in animals and humans. Immune response is enhanced by fusing relevant viral antigens with xenotypic immunoglobulin heavy chain region through a peptide linker and producing the fusion proteins in Baculovirus expression system to incorporate high mannose glycosylation. By virtue of the antibody component, the fusion proteins bind to Fc receptors on the surface of antigen presenting cells, are taken up, processed and derived peptides are presented on MHC Class I, which elicit a CTL (Th1) response. In a similar fashion, due to cross priming and presentation on MHC Class II, will elicit a humoral (Th2) response. In addition, disclosed are the methods of cloning, expression and production of the fusion proteins.

Two-domain MHC polypeptides useful for manipulation of antigen-specific T-cells are disclosed. These polypeptides include MHC class II-based molecules that comprise covalently linked β1 and α1 domains, and MHC class I-based molecules that comprise covalently linked α1 and α2 domains. These polypeptides may also include covalently linked antigenic determinants, toxic moieties, and / or detectable labels. The disclosed polypeptides can be used to target antigen-specific T-cells, and are useful, among other things, to detect and purify antigen-specific T-cells, to induce or activate T-cells, and to treat conditions mediated by antigen-specific T-cells.