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Institution

National Jewish Health

HealthcareDenver, Colorado, United States
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.
Topics: T cell, Asthma, Population, Lung, Antigen


Papers
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Journal ArticleDOI
TL;DR: These data, coupled with previous observations on the absence of heterologous desensitization between PAF and sIgM receptors, may delineate distinct signaling pathways in human B cells, which may reflect different roles for GTP-binding proteins in the activation of human B Cells.
Abstract: Platelet-activating factor (PAF) stimulates human B cells, resulting in elevation of intracellular calcium and the release of inositol phosphates. This signaling pathway is inhibited in the presence of pertussis (PT) or cholera toxin (CT). Preincubation of human B cells with either toxin, but not their inactive subunits, for 3 h blocked these PAF-induced responses in two B-lymphoblastoid cell lines. This effect was time dependent, with some inhibition noted at 30 min, but only after preincubation for 2-3 h was maximum inhibition achieved. This inhibitory activity was also dose dependent. The toxins blocked both PAF-induced transmembrane uptake of Ca2+ as well as release of Ca2+ from internal stores, and were selective in that activation events after cross-linking of surface IgM were not affected. Further, the toxins did not appear to act through elevation of intracellular levels of cAMP. These data, coupled with previous observations on the absence of heterologous desensitization between PAF and sIgM receptors, may delineate distinct signaling pathways in human B cells. This may reflect different roles for GTP-binding proteins in the activation of human B cells.

20 citations

Journal ArticleDOI
TL;DR: Data demonstrate that Arg343 is critical for hSP-D recognition specificity and plays a key role in defining ligand specificity differences between MBP and SP-D and suggest that the number of binding orientations contributes to monosaccharide binding affinity.
Abstract: Surfactant protein D (SP-D), one of the members of the collectin family of C-type lectins, is an important component of pulmonary innate immunity. SP-D binds carbohydrates in a calcium-dependent manner, but the mechanismsgoverning its ligand recognition specificity are not well understood. SP-D binds glucose (Glc) stronger than N-acetylglucosamine (GlcNAc). Structural superimposition of hSP-D with mannose-binding protein C (MBP-C) complexed with GlcNAc reveals steric clashes between the ligand and the side chain of Arg 3 4 3 in hSP-D. To test whether Arg 3 4 3 contributes to Glc > GlcNAc recognition specificity, we constructed a computational model of Arg 3 4 3 - →Val (R343V) mutant hSP-D based on homology with MBP-C. Automated docking of α-Me-Glc and α-Me-GlcNAc into wild-type hSP-D and the R343V mutant of hSP-D suggests that Arg 3 4 3 is critical in determining ligand-binding specificity by sterically prohibiting one binding orientation. To empirically test the docking predictions, an R343V mutant recombinant hSP-D was constructed. Inhibition analysis shows that the R343V mutant binds both Glc and GlcNAc with higher affinity than the wild-type protein and that the R343V mutant binds Glc and GlcNAc equally well. These data demonstrate that Arg 3 4 3 is critical for hSP-D recognition specificity and plays a key role in defining ligand specificity differences between MBP and SP-D. Additionally, our results suggest that the number of binding orientations contributes to monosaccharide binding affinity.

20 citations

Journal ArticleDOI
TL;DR: It is suggested that dexamethasone can stimulate G1-S phase cell cycle transition in human airway fibroblasts obtained from asthmatics, which leads to enhanced airway remodelling in some individuals remains to be determined.
Abstract: Corticosteroids are the first line of therapy for asthma. Whether they alter the progression of airway remodelling in asthma is, as yet, unknown. To determine whether corticosteroids could alter the fibroblast cell cycle the current authors studied the effect of dexamethasone on cultured airway fibroblasts obtained from nine mild-to-moderate, steroid-naive asthmatics (forced expiratory volume in one second 78+/-4% predicted), and seven normal controls. Fibroblasts were cultured from endobronchial biopsies obtained via bronchoscopy. Cells were exposed to dexamethasone (10(-9)-10(-7) M) and studied at 72 h to determine differences in progression through the cell cycle. In asthmatic fibroblasts, dexamethasone, at concentrations of 10(-8)M and 10(-7)M, nearly doubled the number of cells in the S phase (17.8+/-3.0% and 18.4+/-3.1%, respectively) compared with untreated fibroblasts (10.3+/-1.4%). There was no significant effect in normal control fibroblasts. Dexamethasone induced hyperphosphorylation of the tumour suppressor, retinoblastoma (RB) in asthmatic fibroblasts; fibroblasts from normal controls had significantly less hyperphosphorylation of RB. No difference in protein expression of the CCAAT/enhancer binding protein alpha between the two groups was detected. This study suggests that dexamethasone can stimulate G1-S phase cell cycle transition in human airway fibroblasts obtained from asthmatics. Whether this leads to enhanced airway remodelling in some individuals remains to be determined.

20 citations

Journal ArticleDOI
TL;DR: In this review, the transfer of food allergy by transfusion, bone marrow transplantation, and the transplantation of different solid organs is explored, and potential mechanisms in addition to the importance of careful monitoring are discussed.
Abstract: The inadvertent transfer of food allergy from an allergic donor to an unsuspecting recipient by transfusion or organ donation is a relatively rare but intriguing event with potentially catastrophic consequences Additionally, the development of food allergy in the recipient of a transplant from a donor who was not food allergic poses questions about why this occurs, why it is observed more frequently in some situations than others, and the mechanisms that may be involved In this review, the transfer of food allergy by transfusion, bone marrow transplantation, and the transplantation of different solid organs is explored, and potential mechanisms in addition to the importance of careful monitoring are discussed

20 citations

Journal ArticleDOI
TL;DR: Recent data with an artificial substrate for somatic mutation suggest that the mutations are increased by increased stability of the secondary structures in the nascent RNA, and the specific nucleotides that are mutated are due to preferences of a mutator factor.
Abstract: This review describes studies on somatic hypermutation of immunoglobulin genes that were started in the mid-80s in collaboration with Ralph Brinster. Almost all of the experiments were carried out using Ig transgenes as targets for the somatic mutation mechanism. Ig transgenes can be very good targets of somatic mutation, despite many different transgene integration sites. Thus, the required cis-acting elements must be present within the approximately 10 kb of the transgene. Only the Ig variable region and its proximate flanks are mutated, not the constant region in unmanipulated sequences. Several Ig gene enhancers are permissive for somatic mutation and they do not have to be associated with the Ig promoter they normally interact with. However, the mutation process does seem to be specific for Ig genes. No mutations were found in several housekeeping genes isolated from cells that had very high levels of somatic hypermutation of their Ig genes. This suggests that the Ig enhancers provide the lg gene specificity. An exception is the Bcl-6 gene, encoding a transcription factor, which was found to be mutated in normal human memory B cells. When the transcriptional promoter that is located upstream of the variable region is duplicated upstream of the constant region, this region is mutated as well. This suggests a transcription coupled model in which a mutator factor associates with the RNA polymerase at the initiation of transcription, travels with the polymerase during elongation, and causes mutations during polymerase pausing. Our recent data with an artificial substrate for somatic mutation suggest that the mutations are increased by increased stability of the secondary structures in the nascent RNA, and the specific nucleotides that are mutated are due to preferences of a mutator factor.

20 citations


Authors

Showing all 901 results

NameH-indexPapersCitations
Thomas V. Colby12650160130
John W. Kappler12246457541
Donald Y.M. Leung12161450873
Philippa Marrack12041654345
Jeffrey M. Drazen11769352493
Peter M. Henson11236954246
David A. Schwartz11095853533
David A. Lynch10871459678
Norman R. Pace10129750252
Kevin K. Brown10038747219
Stanley J. Szefler9955437481
Erwin W. Gelfand9967536059
James D. Crapo9847337510
Yang Xin Fu9739033526
Stephen D. Miller9443330499
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Performance
Metrics
No. of papers from the Institution in previous years
YearPapers
20233
202214
202113
202017
201917
201841