National Jewish Health

About: National Jewish Health is a healthcare organization based out in Denver, Colorado, United States. It is known for research contribution in the topics: T cell & Asthma. The organization has 883 authors who have published 833 publications receiving 79201 citations. The organization is also known as: National Jewish Medical and Research Center.

Cystatin C antagonizes transforming growth factor beta signaling in normal and cancer cells.

Abstract: Cystatin C (CystC) is a secreted cysteine protease inhibitor that regulates bone resorption, neutrophil chemotaxis, and tissue inflammation, as well as resistance to bacterial and viral infections. CystC is ubiquitously expressed and present in most bodily fluids where it inhibits the activities of cathepsins, a family of cysteine proteases that can promote cancer cell invasion and metastasis. Transforming growth factor beta (TGF-beta) is a multifunctional cytokine endowed with both tumor-suppressing and tumor-promoting activities. We show herein that TGF-beta treatment up-regulated CystC transcript and protein in murine 3T3-L1 fibroblasts. Moreover, CystC mRNA expression was down-regulated in approximately 50% of human malignancies, particularly cancers of the stomach, uterus, colon, and kidney. Overexpression of CystC in human HT1080 fibrosarcoma cells antagonized their invasion through synthetic basement membranes in part via a cathepsin-dependent pathway. Independent of effects on cathepsin activity, CystC also reduced HT1080 cell gene expression stimulated by TGF-beta. Invasion of 3T3-L1 cells occurred through both cathepsin- and TGF-beta-dependent pathways. Both pathways were blocked by CystC, but only the TGF-beta-dependent pathway was blocked by a CystC mutant (i.e., delta14CystC) that is impaired in its ability to inhibit cathepsin activity. Moreover, CystC and delta14CystC both inhibited 3T3-L1 cell gene expression stimulated by TGF-beta. We further show that CystC antagonized TGF-beta binding to its cell surface receptors, doing so by interacting physically with the TGF-beta type II receptor and antagonizing its binding of TGF-beta. Collectively, our findings have identified CystC as a novel TGF-beta receptor antagonist, as well as a novel CystC-mediated feedback loop that inhibits TGF-beta signaling.

Mast cell tumor necrosis factor α production is regulated by MEK kinases

Abstract: Mast cells synthesize and secrete specific cytokines and chemokines which play an important role in allergic inflammation. Aggregation of the high-affinity Fc receptor (FcɛRI) for immunoglobulin E (IgE) in MC/9 mouse mast cells stimulates the synthesis and secretion of tumor necrosis factor α (TNF-α). FcɛRI aggregation activates several sequential protein kinase pathways, leading to increased activity of extracellular signal-regulated kinases (ERKs), c-Jun amino-terminal kinases (JNKs), and the p38 mitogen-activated protein (MAP) kinase. Inhibition of ERKs with the compound PD 098059 had little effect on FcɛRI-stimulated TNF-α production. Aggregation of FcɛRI stimulated MEK kinase 1 (MEKK1) activity, which activates JNK kinase (JNKK), the kinase that phosphorylates and activates JNKs. Expression of activated MEKK1 (ΔMEKK1) in MC/9 cells strongly stimulated JNK activity but only weakly stimulated p38 activity, and it induced a large activation of TNF-α promoter-regulated luciferase gene expression. Inhibitory mutant JNK2 expressed in MC/9 cells significantly blunted FcɛRI stimulation of TNF-α promoter-driven luciferase expression. Wortmannin, an inhibitor of phosphatidylinositol 3-kinase, diminished FcɛRI-mediated TNF-α synthesis, significantly blunted JNK activation and TNF-α promoter-driven luciferase expression, and only weakly inhibited p38 kinase activation. Inhibition of NFκB activation resulting from ΔMEKK1 expression or FcɛRI stimulation did not affect TNF-α promoter-driven luciferase expression. Our findings define a MEKK-regulated JNK pathway activated by FcɛRI that regulates TNF-α production in mast cells.

The role of glutathione in lymphocyte activation. I. Comparison of inhibitory effects of buthionine sulfoximine and 2-cyclohexene-1-one by nuclear size transformation.

Abstract: The role of glutathione (GSH) in lectin-induced lymphocyte activation can be studied by quantitating lectin-induced nuclear size transformation in the presence of variable degrees of GSH depletion. Buthionine sulfoximine (BSO) inhibits intracellular GSH synthesis by inhibition of the enzyme gamma-glutamyl-cysteine synthetase. By combining endogenous GSH depletion in cell cultures with BSO-induced inhibition of GSH synthesis, lectin-induced lymphocyte activation can be studied at various concentrations of soluble intracellular GSH. With this approach, the percentage of lymphocytes undergoing a nuclear size transformation is minimally affected despite depletion of soluble intracellular GSH to 0.27 nmol/10(7) cells (PBL), which represents approximately 95% depletion of intracellular GSH. When soluble intracellular GSH is depleted to undetectable levels (less than 0.10 nmol/10(7) cells) there is a 10 to 12% reduction in the number of cell nuclei transformed. However, in all BSO-pretreated cultures the lectin-induced nuclear size transformation is intermediate between resting and blast-transformed lymphocytes, suggesting only partial (or aborted) activation. The partial activation response observed in BSO-pretreated cultures may be due to mobilization of the protein-bound pool of GSH, which is relatively resistant to depletion by BSO. That the inhibition of full blast transformation is truly due to GSH depletion was proven by experiments in which GSH was repleted exogenously and a full blast transformation was restored. The results of previous work in our laboratory had shown that the sulfhydryl-reactive agent 2-cyclohexene-1-one (2-CHX) was a potent inhibitor of activation at soluble intracellular GSH concentrations well above 0.27 nmol/10(7) PBL. In the present study, the dose-dependent inhibition of activation by 2-CHX was confirmed, but it was shown that the degree of inhibition caused by 2-CHX could be at least partially dissociated from the level of intracellular GSH present at the time of lectin addition and that the inhibitory potential of 2-CHX exceeded that of BSO at comparable levels of soluble intracellular GSH. Thus, the inhibitory properties of 2-CHX cannot be accounted for solely on the basis of GSH depletion.

Analysis of the New Zealand Black contribution to lupus-like renal disease. Multiple genes that operate in a threshold manner.

Abstract: F1 progeny of New Zealand Black (NZB) and New Zealand White (NZW) mice spontaneously develop an autoimmune process remarkably similar to human systemic lupus erythematosus. Previous studies have implicated major genetic contributions from the NZW MHC and from a dominant NZB gene on chromosome 4. To identify additional NZB contributions to lupus-like disease, (NZB x SM/J)F1 x NZW backcross mice were followed for the development of severe renal disease and were comprehensively genotyped. Despite a 50% incidence of disease, significant associations between the presence of the NZB genotype and disease were noted on chromosomes 1, 4, 7, 10, 13, and 19. The data indicated that multiple NZB genes, in different combinations, contribute to severe renal disease, and that no single gene is required. To further investigate this NZB contribution, NZB x SM/J (NXSM) recombinant inbred (RI) strains were crossed with NZW mice, and F1 progeny were analyzed for the presence of lupus-like renal disease. Interestingly, nearly all of the (RI x NZW)F1 cohorts studied expressed some level of disease. Five RI strains generated a high incidence of disease, similar to (NZB x NZW)F1 mice, and nearly one-half of the cohorts developed disease at intermediate levels. Only two cohorts demonstrated very little disease, supporting the conclusion that multiple genes are capable of disease induction. Experiments correlating the genotypes of these RI strains with their ability to generate disease revealed that none of the disease-associated loci defined by the backcross analysis were present in all five RI strains that generated disease at high levels. Overall, both the backcross data and RI analysis provide additional support for the genetic complexity of lupus nephritis and uphold the conclusion that heterogeneous combinations of contributing NZB genes seem to operate in a threshold manner to generate the disease phenotype.

Daclizumab improves asthma control in patients with moderate to severe persistent asthma: a randomized, controlled trial.

Abstract: Rationale: Airway inflammation in asthma is associated with increased activated CD25+ T cells, IL-2, and soluble IL-2 receptors (IL-2Rs).Objectives: A randomized, double-blinded, placebo-controlled study was used to evaluate the safety and efficacy of daclizumab, a humanized IgG1 monoclonal antibody against the IL-2R α chain (CD25) of activated lymphocytes, in adults with moderate to severe persistent asthma.Methods: Patients with obstructive pulmonary functions, despite inhaled corticosteroids (ICS), were switched to equivalent dose inhaled triamcinolone acetate acetonide (TAA). Patients dependent on ICS were randomized (3:1) to daclizumab (intravenous loading dose, 2 mg/kg, then 1 mg/kg) or placebo every 2 weeks, added to stable-dose TAA through Week 12 (Treatment Period 1). Over Weeks 12–20 (Treatment Period 2), patients tapered TAA while on the study drug, and were followed for 16 weeks off the study drug.Measurements and Main Results: Among 115 evaluable patients (88 daclizumab, 27 placebo), groups h...