Abstract: A simple and highly efficient method for cloning cDNAs including CD27 (SEQ ID NO:28) from mammalian expression libraries based on transient expression in mammalian host cells has been discovered. Novel expression vectors allowing highly efficient construction of mammalian cDNA libraries are disclosed. The cloning method of the invention which has been used to clone genes for cell surface antigens of human lymphocytes, has general application in gene cloning. Cell surface antigens cloned according to the present invention have been purified, and the nucleotide and amino acid sequences determined. These antigens have diagnostic and therapeutic utility in immune-mediated infections in mammals, including humans.

Abstract: The present invention provides a method for inhibiting an immune reponse and a method for inhibiting rejection of transplanted tissues. This method comprises preventing an endogenous molecule on a cell selected from the group consisting of gp39 and CD40 antigens from binding its endogenous ligand and preventing an endogenous molecule on a cell selected from the group consisting of CTLA4, CD28, and B7 antigens from binding its endogenous ligand. The prevention of such molecules from binding their ligand thereby blocks two independent signal pathways and inhibits the immune response resulting in transplanted tissue rejection.

Abstract: A simple and highly efficient method for cloning cDNAs from mammalian expression libraries based on transient expression in mammalian host cells has been discovered. Novel expression vectors allowing highly efficient construction of mammalian cDNA libraries are disclosed. The cloning method of the invention which has been used to clone genes for cell surface antigens of human lymphocytes, has general application in gene cloning. Cell surface antigens cloned according to the present invention have been purified, and the nucleotide and amino acid sequences determined. These antigens have diagnostic and therapeutic utility in immune-mediated infections in mammals, including humans.

Abstract: A method of treating graft-vs-host diseases by administration of bone marrow and an anti-gp39 antibody specific to human gp39 is provided.

Abstract: A simple and highly efficient method for cloning cDNAs from mammalian expression libraries based on transient expression in mammalian host cells has been discovered. Novel expression vectors allowing highly efficient construction of mammalian cDNA libraries are disclosed. The cloning method of the invention which has been used to clone genes for cell surface antigens of human lymphocytes, has general application in gene cloning. Cell surface antigens cloned according to the present invention have been purified, and the nucleotide and amino acid sequences determined. These antigens have diagnostic and therapeutic utility in immune-mediated infections in mammals, including humans.

Abstract: The present invention relates, in general, to CD6 and, in particular, to a CD6 ligand present on the surface of thymic epithelial cells, monocytes, activated T cells and a variety of other cell types. The invention further relates to methods of inhibiting the interaction of CD6 and the CD6 ligand, and to methods of screening compounds for their ability to inhibit that interaction. The invention also relates to antibodies, and binding fragments thereof, specific for CD6 ligand.

Abstract: The present invention relates to an isolated nucleic acid molecule having a sequence that encodes a CD6 ligand present on the surface of thymic epithelial cells, monocytes, activated T cells and a variety of other cell types. The invention further relates to a construct containing the nucleic acid molecule and to a host cell comprising same. Further, the invention relates to a method of producing a CD6 ligand.

Abstract: The present invention relates to fusion proteins having gp39 protein sequences, which fusion proteins bind to the B cell antigen, CD40. More specifically, the invention relates to fusion proteins having gp39 protein sequences attached to a polypeptide having an amino terminal secretory signal sequence to allow export of the fusion protein out of the recombinant host cell in which it is produced. The fusion proteins of this invention may be useful for promoting B cell proliferation.

Abstract: Antibodies that bind a protein gp39 (also referred to as CD40 ligand) are disclosed. Preferably, the antibodies are monoclonal antibodies of an IgG1 isotype and bind human gp39. In a preferred embodiment, an antibody of the invention binds an epitope recognized by a monoclonal antibody 24-31, produced by a hybridoma 24-31 (ATTC Accession No. HB11712) or binds an epitope recognized by a monoclonal antibody 89-76, produced by a hybridoma 89-76 (ATCC Accession No. HB 11713). Pharmaceutical compositions comprising the antibodies of the invention are also disclosed. The antibodies of the invention are useful for inhibiting B cell proliferation and differentiation, T cell responses and for inducing T cell tolerance. Nucleic acid molecules encoding anti-gp39 antibodies, or portions thereof, as well as expression vectors and host cells incorporating said nucleic acid molecules, are also encompassed by the invention.

Abstract: A simple and highly efficient method for cloning cDNAs from mammalian expression libraries based on transient expression in mammalian host cells has been discovered. The present invention specifically provides the CD40 cDNA sequence.

Abstract: A simple and highly efficient method for cloning cDNAs from mammalian expression libraries based on transient expression in mammalian host cells has been discovered. Novel expression vectors allowing highly efficient construction of mammalian cDNA libraries are disclosed. The cloning method of the invention which has been used to clone genes for cell surface antigens of human lymphocytes, has general application in gene cloning. Cell surface antigens cloned according to the present invention have been purified, and the nucleotide and amino acid sequences determined. These antigens have diagnostic and therapeutic utility in immune-mediated infections in mammals, including humans.

Abstract: Antibodies that bind a protein gp39 (also referred to as CD40 ligand) are disclosed. Preferably, the antibodies are monoclonal antibodies of an IgG1 isotype and bind human gp39. In a preferred embodiment, an antibody of the invention binds an epitope recognized by a monoclonal antibody 24-31, produced by a hybridoma 24-31 (ATTC Accession No. HB11712) or binds an epitope recognized by a monoclonal antibody 89-76, produced by a hybridoma 89-76 (ATCC Accession No.HB11713). Pharmaceutical compositions comprising the antibodies of the invention are also disclosed. The antibodies of the invention are useful for inhibiting B cell proliferation and differentiation, T cell responses and for inducing T cell tolerance. Nucleic acid molecules encoding anti-gp39 antibodies, or portions thereof, as well as expression vectors and host cells incorporating said nucleic acid molecules, are also encompassed by the invention.

Abstract: The present invention relates, in general, to CD6 and, in particular, to a CD6 ligand present on the surface of thymic epithelial cells, monocytes, activated T cells and a variety of other cells types. The invention further relates to methods of inhibiting the interaction of CD6 and the CD6 ligand, and to the methods of screening componunds for their ability to inhibit that interaction.

Abstract: The present invention definitively identifies and characterizes the tumor-associated antigen immunologically recognized by the murine monoclonal antibody L6. Further, the present invention provides the nucleotide sequence which encodes the L6 antigen. Various diagnostic, prophylactic and therapeutic methods comprising the L6 antigen and the nucleotide sequence which encodes the L6 antigen are also provided.

Abstract: The present invention relates to soluble ligands for the B-cell antigen, CD40, and, in particular, to human gp39 protein and soluble ligands derived therefrom which may be used in methods of promoting B-cell proliferation.

Abstract: A simple and highly efficient method for cloning cDNAs from mammalian expression libraries based on transient expression in mammalian host cells has been discovered. Novel expression vectors allowing highly efficient construction of mammalian cDNA libraries are disclosed. The cloning method of the invention which has been used to clone genes for cell surface antigens of human lymphocytes, has general application in gene cloning. Cell surface antigens cloned according to the present invention have been purified, and the nucleotide and amino acid sequences determined. These antigens have diagnostic and therapeutic utility in immune-mediated infections in mammals, including humans.