Respiratory System Commons^™

Do Cd1-Restricted T Cells Contribute To Antibody-Mediated Immunity Against Mycobacterium Tuberculosis?, Mark L. Lang, Aharona Glatman-Freedman

Dartmouth Scholarship

No abstract provided.

Tgf-Beta1 And Serum Both Stimulate Contraction But Differentially Affect Apoptosis In 3d Collagen Gels, Tetsu Kobayashi, Xiangde Liu, Hui Jung Kim, Tadashi Kohyama, Fu-Qiang Wen, Shinji Abe, Qiuhong Fang, Yun Kui Zhu, John R. Spurzem, Peter Bitterman, Stephen I. Rennard

Journal Articles: Pulmonary & Critical Care Med

Apoptosis of fibroblasts may be key for the removal of cells following repair processes. Contraction of three-dimensional collagen gels is a model of wound healing and remodeling. Here two potent inducers of contraction, TGF-beta1 and fetal calf serum (FCS) were evaluated for their effect on fibroblast apoptosis in contracting collagen gels. Human fetal lung fibroblasts were cultured in floating type I collagen gels, exposed to TGF-beta1 or FCS, and allowed to contract for 5 days. Apoptosis was evaluated using TUNEL and confirmed by DNA content profiling. Both TGF-beta1 and serum significantly augmented collagen gel contraction. TGF-beta1 also increased apoptosis assessed …

Bronchial Airway Epithelial Cell Denudation In The Pathogenesis Of Asthma: The Role Of Il-4 And Il-13, Gail Ramirez-Icaza

All-Inclusive List of Electronic Theses and Dissertations

Asthma is characterized by infiltration and shedding of the bronchial epithelium. The Th2 cytokines IL-4 and IL-13 are involved in the cellular recruitment and infiltration seen in asthma. The effects ofIL-4 and IL-13 on cell-matrix interactions, gap formation, increased monolayer permeability and epithelial shedding are unknown. Experiments described in this report test the hypothesis that bronchial airway epithelial cells (BAEC) express paxillin, a structural focal adhesion protein, and down-regulation of paxillin by Th2 cytokines lead to BAEC hyperpermeability. Furthermore, the hypothesis that the Th2 cytokines IL-4 and IL-13 could down-regulate the adherens junction proteins Pcatenin and E-cadherin in BAEC, and …

Platelets Stimulate Fibroblast-Mediated Contraction Of Collagen Gels, Ulrika Zagai, Karin Fredriksson, Stephen I. Rennard, Joachim Lundahl, C. Magnus Sköld

Journal Articles: Pulmonary & Critical Care Med

BACKGROUND: Platelets are thought to play a role in a variety of inflammatory conditions in the lung, some of which may lead to fibrosis. In the current study we tested the hypothesis that whole platelets and platelet lysate can mediate remodelling of extracellular matrix in vitro by affecting fibroblast-mediated contraction of a collagen gel. We also sought to determine to what extent platelet-derived growth factor (PDGF) and transforming growth factor-beta (TGF-beta) contribute to this effect.

METHODS: Washed platelets, isolated from healthy blood donors, and platelet lysate (freezing and thawing), were cast together with human lung fibroblasts in three-dimensional collagen gels. …

Staphylococcus Aureus Agr And Sara Functions Are Required For Invasive Infection But Not Inflammatory Responses In The Lung, Geoffrey Heyer, Shahryar Saba, Robert Adamo, William Rush, Grace Soong, Ambrose Cheung, Alice Prince

Dartmouth Scholarship

Staphylococcus aureus strains lacking agr- and sarA-dependent gene products or specific MSCRAMM (microbial surface components recognizing adhesive matrix molecules) adhesins were compared for the ability to activate inflammatory responses in the lung. The mutants were evaluated for virulence in a mouse model of pneumonia and by quantifying their ability to stimulate interleukin-8 (IL-8) and granulocyte-macrophage colony-stimulating factor (GM-CSF) expression in respiratory epithelial cells. In a neonatal mouse, only strains with intact agr and sarA loci were consistently associated with invasive, fatal pulmonary infection (P < 0.001) and sarA was specifically required to cause bacteremia (P < 0.001). The agr and/or sarA mutants were, nonetheless, fully capable of producing pneumonia and were as proficient as the wild-type strain in stimulating epithelial IL-8 expression, a polymorphonuclear leukocyte chemokine, in airway cells. In contrast, agr and especially sarA mutants induced less epithelial GM-CSF expression, and MSCRAMM mutants lacking fibronectin binding proteins or clumping factor A, a ligand for fibrinogen, were unable to stimulate epithelial GM-CSF production. The ability to induce IL-8 expression was independent of the adherence properties of intact bacteria, indicating that shed and/or secreted bacterial components activate epithelial responses. While conserved staphylococcal components such as peptidoglycan are sufficient to evoke inflammation and cause pneumonia, the agr and sarA loci of S. aureus are critical for the coordination of invasive infection of the lungs.

Staphylococcus Aureus Rn6390 Replicates And Induces Apoptosis In A Pulmonary Epithelial Cell Line, Barbara C. Kahl, Mark Goulian, Willem Van Wamel, Mathias Herrmann, Sanford M. Simon, Gilla Kaplan, Georg Peters, Ambrose L. Cheung

Dartmouth Scholarship

Staphylococcus aureus frequently colonizes the airways of patients with compromised airway defenses (e.g., cystic fibrosis [CF] patients) for extended periods. Persistent and relapsing infections may be related to live S. aureus bacteria actively residing inside epithelial cells. In this study, we infected a respiratory epithelial cell line, which was derived from a CF patient, with S. aureus RN6390. Internalization of S. aureus was found to be time and dose dependent and could be blocked by cytochalasin D. Transmission electron microscopy revealed that internalized bacteria resided within endocytic vacuoles without any evidence of lysosomal fusion in a 24-h period. The results …

Repair Of The Airway Epithelium: Potential Opportunities For Therapeutic Intervention In Airway Disease, Stephen I. Rennard

Journal Articles: Pulmonary & Critical Care Med

The epithelium of the airway has considerable capacity to undergo repair. These repair processes are responsible for maintaining and restoring function after injury of the airways, which likely occurs often as a result of infectious, toxic or other exposures. However, repair processes need not be fully effective. Inadequate repair can take a number of forms and may result in metaplasia, hyperplasia or fibrotic scarring. It is likely that repair processes that lead to tissue disruption play an important role in the chronic airways diseases, such as asthma and bronchitis. Through delineation of these processes, it may become feasible to target …

Efficient Vasoactive Intestinal Polypeptide Hydrolyzing Autoantibody Light Chains Selected By Phage Display, Sonia Tyutyulkova, Qing-Sheng Gao, Austin Thompson, Stephen I. Rennard, Sudhir Paul

Journal Articles: Pulmonary & Critical Care Med

An immunoglobulin light chain (L chain) library derived from the peripheral blood lymphocytes of a patient with asthma was cloned into a phagemid vector. Phage particles displaying L chains capable of binding vasoactive intestinal polypeptide (VIP) were isolated by affinity chromatography. Two VIP binding L chains were expressed in Escherichia coli in soluble form and purified to electrophoretic homogeneity by metal chelating and protein L affinity chromatography. Both L chains catalyzed the hydrolysis of [tyr10-125I]VIP substrate. The catalytic activity eluted at the molecular mass of the monomer form of the L chain (28 kDa) from a gel filtration column. The …

Respiration In The Newborn Infant, A. Robert Bauer, Philip J. Howard

Henry Ford Hospital Medical Journal

No abstract provided.

Oxygen Physiology, Normal And Abnormal, Donald D. Van Slyke

Henry Ford Hospital Medical Journal

No abstract provided.