Abstract: Primitive hematopoietic stem cells are closely associated with discrete in vivo microenvironments. These “niches” are thought to provide the molecular signals that mediate stem cell differentiation and self renewal. We have dissected the fetal liver microenvironment into distinct cellular components by establishing an extensive panel of stromal cell lines. One particular cell line maintains repopulating stem cells for prolonged in vitro culture periods. A subtraction cloning strategy has yielded a cDNA which encodes a cell surface glycoprotein with a restricted pattern of expression among stromal cell lines. This molecule, previously identified as dlk/Pref-1, contains EGF-like repeats which are related to those in the Notch/Delta/Serrate family of proteins. We have investigated the potential role of this molecule in hematopoietic stem/progenitor cell regulation.

Abstract: The present invention provides an isolated nucleic acid molecule that encodes an amino acid sequence comprising a FrpB protein. The invention also provides vaccine compositions capable of protecting a mammal against infection by N. gonorrhoeae or N. meningitidis comprising the FrpB protein encoded by the isolated nucleic acid of the invention and a pharmaceutically acceptable carrier.

Abstract: Iron-regulated, outer membrane proteins found in Neisseria gonorrhoeae and Neisseria meningitidis are important in transferrin receptor function. The proteins, which are isolatable by means of a transferrin affinity column, bind specifically to antisera raised against an iron-regulated outer membrane protein having a molecular weight of approximately 100 kD found in Neisseria gonorrhoeae.

Abstract: The present invention is directed to a method of amplifying and detecting single or double stranded target nucleic acid molecules. Amplification of the target nucleic acid molecule is accomplished by using at least two chemically modified oligonucleotide probes per target nucleic acid molecule to form a joined oligonucleotide product. Each oligonucleotide probe is comprised of a long and short sequence. The long sequence of each probe hybridizes to adjacent regions of the target nucleic acid molecule. The short sequences of each probe hybridize to each other. Chemical functionality groups attached to the short sequences of each oligonucleotide probe covalently combine linking the probes to form a joined oligonucleotide product. The joined oligonucleotide product is formed without the use of enzymes.The reactivity of the chemical functionality groups on each probe is target dependent.

Abstract: The invention provides a method of diagnosing cancer by determining the expression level or gene amplification of p53 and dm2, whereby an elevated level of either p53 or dm2 or both p53 and dm2 indicates a cancer diagnosis. Furthermore, the invention provides a method of predicting the progress of cancer by determining the expression level or gene amplification of p53 and dm2, whereby an elevated level of either p53 or dm2 or both p53 and dm2 indicated a poor prognosis.

Abstract: Isolated mammalian nucleic acid molecules encoding receptor protein tyrosine kinases expressed in primitive hematopoietic cells and not expressed in mature hematopoietic cells are provided. Also included are the receptors encoded by such nucleic acid molecules; the nucleic acid molecules encoding receptor protein tyrosine kinases having the sequences shown in FIG. 1a (murine flk-2), FIG. 1b (human flk-2) and FIG. 2 (murine flk-1); the receptor protein tyrosine kinases having the amino acid sequences shown in FIG. 1a, FIG. 1b and FIG. 2; ligands for the receptors; nucleic acid sequences that encode the ligands; and methods of stimulating the proliferation and/or differentiation of primitive mammalian hematopoietic stem cells comprising contacting the stem cells with a ligand that binds to a receptor protein tyrosine kinase expressed in primitive mammalian hematopoietic cells and not expressed in mature hematopoietic cells.

Abstract: Isolated mammalian nucleic acid molecules encoding receptor protein tyrosine kinases expressed in primitive hematopoietic cells and not expressed in mature hematopoietic cells are provided. Also included are the receptors encoded by such nucleic acid molecules; the nucleic acid molecules encoding receptor protein tyrosine kinases having the sequences shown in FIG. 1A (murine flk-2), FIG. 1B (human flk-2) and FIG. 2 (murine flk-1); the receptor protein tyrosine kinases having the amino acid sequences shown in FIG. 1A, FIG. 1B and FIG. 2; ligands for the receptors; nucleic acid sequences that encode the ligands; and methods of stimulating the proliferation and/or differentiation of primitive mammalian hematopoietic stem cells comprising contacting the stem cells with a ligand that binds to a receptor protein tyrosine kinase expressed in primitive mammalian hematopoietic cells and not expressed in mature hematopoietic cells.

Abstract: This invention relates to a Carboxy Terminal IL-6 Mutein with enhanced biological activity. The invention comprises a mutein of IL-6 having increased activity wherein the mutein has an amino acid substitution at, or corresponding to, amino acid location 171 or 175 of IL-6 having the wild-type sequence.

Abstract: Isolated mammalian nucleic acid molecules encoding receptor protein tyrosine kinases expressed in primitive hematopoietic cells and not expressed in mature hematopoietic cells are provided. Also included are the receptors encoded by such nucleic acid molecules; the nucleic acid molecules encoding receptor protein tyrosine kinases having the sequences shown in FIG. 1a (murine flk-2), FIG. 1b (human flk-2) and FIG. 2 (murine flk-1); the receptor protein tyrosine kinases having the amino acid sequences shown in FIG. 1a, FIG. 1b and FIG. 2; ligands for the receptors; nucleic acid sequences that encode the ligands; and methods of stimulating the proliferation and/or differentiation of primitive mammalian hematopoietic stem cells comprising contacting the stem cells with a ligand that binds to a receptor protein tyrosine kinase expressed in primitive mammalian hematopoietic cells and not expressed in mature hematopoietic cells.

Abstract: The present invention provides a polypeptide that is non-toxic in E. coli. The disclosed polypeptide comprises at least one antigenic sequence present in P.IA of N. gonorrhoeae and at least one antigenic sequence present in P.IB of N. gonorrhoeae. Further, the disclosed polypeptide of the invention is fused to a carrier peptide.

Abstract: Muteins of IL-6 and truncated IL-6 are prepared by recombinant DNA techniques. In the muteins, the cysteine residues that occur at positions, or at positions corresponding to positions, 45 and 51 of mature, native IL-6 have been replaced by other amino acids. The cysteine residues that occur at positions, or at positions corresponding to positions, 74 and 84 are retained. The molecule has biological activity that is at least comparable to that of native IL-6.