Expression and activity of ADAMTS-5 in synovium.

ADAMTS proteinases, belonging to the adamalysin subfamily of metalloproteinases, have been implicated in a variety of cellular events such as morphogenesis, cell migration, angiogenesis, ovulation and extracellular matrix breakdown. Aggrecanase-1 (ADAMTS-4) and aggrecanase-2 (ADAMTS-5) have been identified in cartilage and are largely responsible for cartilage aggrecan breakdown. We have shown previously that synovium, the membrane lining diarthrodial joints, generates soluble aggrecanase activity.

ADAMTS9, a novel member of the ADAM-TS/ metallospondin gene family.

ADAM-TS/metallospondin genes encode a new family of proteins with structural homology to the ADAM metalloprotease-disintegrin family. However, unlike other ADAMs, these proteins contain thrombospondin type 1 (TSP1) repeats at the carboxy-terminal end and are secreted proteins instead of being membrane bound. Members of the ADAM-TS family have been implicated in the cleavage of proteoglycans, the control of organ shape during development, and the inhibition of angiogenesis.

The copper transport protein Atox1 promotes neuronal survival.

Atox1, a copper transport protein, was recently identified as a copper-dependent suppressor of oxidative damage in yeast lacking superoxide dismutase. We have previously reported that Atox1 in the rat brain is primarily expressed in neurons, with the highest levels in distinct neuronal subtypes that are characterized by their high levels of metal, like copper, iron, and zinc. In this report, we have transfected the Atox1 gene into several neuronal cell lines to increase the endogenous level of Atox1 expression and have demonstrated that, under conditions of serum starvation and oxidative injury, the transfected neurons are significantly protected against this stress.

Nephroblastoma overexpressed gene (NOV) codes for a growth factor that induces protein tyrosine phosphorylation.

NOV (nephroblastoma overexpressed gene) is a member of the CCN (connective tissue growth factor [CTGF], Cyr61/Cef10, NOV) family of proteins. These proteins are cysteine-rich and are noted for having growth-regulatory functions. We have isolated the rat NOV gene, and the DNA sequence shares 90% identity with the mouse and 80% identity with the human sequences.

Expression profile of the copper homeostasis gene, rAtox1, in the rat brain.

In humans the regulation of cellular copper homeostasis is essential for proper organ development and function. A novel cytosolic protein, named Atox 1, was recently identified in yeast that functions in shuttling intracellular mononuclear copper [Cu(I)] to copper-requiring proteins. Atox 1 and its human homolog, hAtox1, are members of an emerging family of proteins termed copper chaperones that are involved in the maintenance of copper homeostasis.

Subtractive hybridization of cDNA libraries.

The technique of subtractive hybridization is used to enrich abundant cDNAs that differ between two cell populations. This approach is well suited for systems in which a homogenous cell population is activated in culture with an agent or factor that induces the transcription of genes that are either not present or at low abundance in the unactivated state. Whereas this scenario is the ideal model, models of comparison between heterogeneous cell cultures or even tissues have been analyzed by subtractive hybridization with success.

Murine GBP-2: a new IFN-gamma-induced member of the GBP family of GTPases isolated from macrophages.

We have cloned a new member of the interferon (IFN)-induced guanylate-binding protein (GBP) family of GTPases, murine GBP-2 (mGBP-2), from bone marrow-derived macrophages. mGBP-2 is located on murine chromosome 3, where it is linked to mGBP-1. With the identification of mGBP-2 there are now two human and two murine GBPs.

Selective chemokine mRNA accumulation in the rat spinal cord after contusion injury.

Following traumatic injury to the spinal cord, hematogenous inflammatory cells including neutrophils, monocytes, and lymphocytes infiltrate the lesion in a distinct temporal sequence. To examine potential mechanisms for their recruitment, we measured chemokine mRNAs in the contused rat spinal cord, using specific and sensitive reverse transcriptase polymerase chain reaction (RT-PCR) dot-blot hybridization assays. The neutrophil chemoattractant GRO-alpha was 30-fold higher than control values at 6 hr postinjury and decayed rapidly thereafter.

Rat p67 GBP is induced by interferon-gamma and isoprenoid-modified in macrophages.

The guanylate binding proteins, GBPs, are a family of interferon-induced GTP-binding proteins that include the rat p67. We report here that rat p67, for which interferon regulation had not previously been demonstrated, is induced by IFN-gamma and also by LPS in both cultured bone marrow-derived macrophages and microglia. The basal level of rat p67 in macrophages is low but increases dramatically between 2 and 4 hours after treating cells with either IFN-gamma or LPS.

Molecular cloning and functional characterization of human lymphotactin.

We describe the isolation of a cDNA that encodes human lymphotactin (Ltn), a new class of lymphocyte-specific chemokine. Human Ltn shows similarity to some members of the C-C chemokine family but has lost the first and third cysteine residues that are characteristic of the C-C and C-X-C chemokines. Ltn is chemotactic for lymphocytes but not for monocytes, a characteristic that makes it unique among chemokines.

Cytokine production profile of early thymocytes and the characterization of a new class of chemokine.

By using a variety of molecular techniques, we have characterized the cytokine profile of pro-T cells. During this characterization we cloned a novel cytokine that has chemotactic activities. We have designated this cytokine lymphotactin.

Lymphotactin: a cytokine that represents a new class of chemokine.

In this study, the cytokine-producing profile of progenitor T cells (pro-T cells) was determined. During screening of a complementary DNA library generated from activated mouse pro-T cells, a cytokine designated lymphotactin was discovered. Lymphotactin is similar to members of both the Cys-Cys and Cys-X-Cys chemokine families but lacks two of the four cysteine residues that are characteristic of the chemokines.

The murine immune response to the male-specific antigen mouse testicular cytochrome c.

Male and female A/J mice were examined for their ability to elicit T lymphocyte and antibody (Ab) responses to the male-specific Ag, mouse testicular cytochrome c (Mt cyt). T lymphocytes from both male and female mice primed in vivo responded to the Ag in in vitro proliferation assays, and the dose-response curves were statistically indistinguishable. In addition, similar levels of Ab to Mt cyt were observed in immunized male and female mice.

A single amino acid substitution in a cytochrome c T cell stimulatory peptide changes the MHC restriction element from one isotype (I-Ak) to another (I-Ek).

The binding sites of class II major histocompatibility complex (MHC) molecules can accommodate many seemingly diverse peptides. In the case of mouse class II molecules, it appears that in general, the I-A and I-E isotypes associate with different peptides. In this study we report an example where a single amino acid substitution in an I-Ak restricted peptide changes the restriction element to I-Ek.