Search results for "Leukocytes"
showing 10 items of 429 documents
Differences in non-MHC restricted cytotoxic activities of human peripheral blood lymphocytes after transfusion with allogeneic leukocytes or platelet…
1990
Abstract MHC-unrestricted cytotoxic activity of peripheral blood lymphocytes (PBL) from 4–6 healthy donors was investigated before and after transfusion with allogeneic leukocytes or platelets. Natural killer and lectin-dependent cellular cytotoxicity (LDCC) of PBL was tested against K562 and Raji target cells in a 4-h and 16-h 51 Cr-release assay, respectively. After allotransfusion with leukocytes, we found increased cytotoxic activity of each donor's PBL against all the three targets on day 3 or 7. The highest non-specific cytotoxic activity was detected against the relatively NK resistant Raji target cells. The increase of cytotoxic activity was lowest against the LDCC target (PHA-treat…
Leukocyte–platelet aggregates—a phenotypic characterization of different stages of peripheral arterial disease
2016
The formation of monocyte-platelet aggregates and neutrophil-platelet aggregates (MPA and NPA, respectively) is influenced by inflammation, but also might contribute to an exacerbation of inflammatory responses in atherosclerotic plaque. The purpose of this study was to analyze MPA and NPA proportions in regard to different stages of peripheral arterial disease (PAD). Forty-five patients with intermittent claudication (IC) (3 groups: Rutherford (R)-1, R-2, and R-3; each n = 15), 20 patients with critical limb ischemia (CLI) (Rutherford 5 (40%) and 6 (60%)), and 20 healthy controls were studied. Analyses of monocyte (Mon) subpopulations (CD14++CD16- (classical) Mon1, CD14++CD16+ (intermediat…
A peptide from the staphylococcal protein Efb binds P‐selectin and inhibits the interaction of platelets with leukocytes
2022
AimsP-selectin is a key surface adhesion molecule for the interaction of platelets with leukocytes. We have shown previously that the N-terminal domain of S. aureus extracellular fibrinogen-binding protein (Efb) binds to P-selectin and interferes with platelet-leukocyte aggregate formation. Here, we aimed to identify the minimal Efb motif required for binding platelets and to characterise its ability to interfering with the formation of platelet-leukocyte aggregates.Methods and ResultsUsing a library of synthetic peptides, we mapped the platelet-binding site to a continuous 20 amino acid stretch. The peptide Efb68-87 was able to bind to resting and, to a greater extent, thrombin-stimulated …
Influence of traditional Chinese anti-inflammatory medicinal plants on leukocyte and platelet functions.
2003
Abstract The enzymes 5-lipoxygenase and elastase are therapeutic targets in dermatological disorders such as psoriasis. Fifteen extracts from traditional Chinese medicinal plants used to treat topical inflammations were screened for their inhibitory effect on lipoxygenase, cyclooxygenase and elastase activity in intact leukocytes and platelets. Astragalus membranaceus, Forsythia suspensa and Poria cocos inhibited 5-lipoxygenase, with IC50 values of 141, 80 and 141 μg mL−1, respectively. The latter two species, along with Angelica dahurica and Angelica pubescens, also inhibited elastase (IC50 values of 80, 123, 68 and 93 μg mL−1, respectively), while A. pubescens, Atractylodes macrocephala, …
Preparation and Application of an Innovative Thrombocyte/Leukocyte-Enriched Plasma to Promote Tissue Repair in Chelonians
2015
Platelet concentrates are widely used in mammalian regenerative medicine to improve tissue healing. Chelonians (Testudines) would benefit from the application of thrombocyte preparations to regenerate damaged tissues, since traumatic injuries are leading causes of morbidity and mortality for both wild-living and domesticated animals. The aim of this study was to establish a protocol that optimized the recovery of the thrombocytes from blood samples and to show the efficacy of thrombocyte-enriched plasma in chelonians. Peripheral blood samples were obtained from Testudo spp. (n = 12) and Trachemys scripta elegans (n = 10). Blood cells were fractionated by sodium diatrizoate-sodium polysucros…
Griffonianone D, an isoflavone with anti-inflammatory activity from the root bark of Millettia griffoniana.
2003
A new isoflavone, griffonianone D (1), and the previously known compounds durmillone and odorantin were isolated from a chloroform extract of the root bark of Millettia griffoniana. The structure of 1 was established as (7E)-(6",7"-dihydroxy-3",7"-dimethyloct-2"-enyl)oxy-4'-methoxyisoflavone on the basis of its spectral data. The chloroform extract of the root bark of M. griffoniana and compound 1 showed anti-inflammatory effects in different experimental models of inflammation.
Bone regeneration at extraction sockets filled with leukocyte-platelet-rich fibrin: An experimental pre-clinical study
2022
We aimed to histomorphometrically evaluate the effects of Leucocyte-Platelet-Rich Fibrin (L-PRF), with and without the combination of a bone grafting material, for alveolar ridge preservation using an in vivo canine model. Seven dogs (Female Beagles, ~18-month-old) were acquired for the study. L-PRF was prepared from each individual animal by drawing venous blood and spinning them through a centrifuge at 408 RCF-clot (IntrasSpin, Intra-Lock, Boca Raton, FL). L-PRF membranes were obtained from XPression fabrication kit (Biohorizons Implant Systems, Inc., AL, USA). A split mouth approach was adopted with the first molar mesial and distal socket defects treated in an interpolated fashion of th…
Antibodies to PECAM-1 and glucocorticoids reduce leukocyte adhesion in adjuvant arthritis of the rat knee synovium in vivo.
2002
Objective and design: To demonstrate the effect of monoclonal antibodies to the adhesion-molecule PECAM-1 (CD31) and of prednisolone on leukocyte adhesion in rat adjuvant arthritis.¶Material: Adjuvant arthritis was induced in male CD®-rats (five groups of n=6) 18 days prior to measurements.¶Treatment: Mouse-monoclonal antibody to rat CD-31 at 200 μg/kg or prednisolone at 24 mg/kg were administered i.v. 15 minutes prior to measurements.¶Methods: Venules within the intact rat-knee synovium were focused by confocal laser scanning microscopy. Numbers of rolling and adherent leukocytes were assessed in vivo.¶Results: Induction of arthritis significantly increased rolling and adherent leukocytes …
Exclusive transduction of human CD4+ T Cells upon systemic delivery of CD4-targeted lentiviral vectors
2015
Abstract Playing a central role in both innate and adaptive immunity, CD4+ T cells are a key target for genetic modifications in basic research and immunotherapy. In this article, we describe novel lentiviral vectors (CD4-LV) that have been rendered selective for human or simian CD4+ cells by surface engineering. When applied to PBMCs, CD4-LV transduced CD4+ but not CD4− cells. Notably, also unstimulated T cells were stably genetically modified. Upon systemic or intrasplenic administration into mice reconstituted with human PBMCs or hematopoietic stem cells, reporter gene expression was predominantly detected in lymphoid organs. Evaluation of GFP expression in organ-derived cells and blood …
Allergen-induced IgE-dependent gut inflammation in a human PBMC-engrafted murine model of allergy.
2011
Background Humanized murine models comprise a new tool to analyze novel therapeutic strategies for allergic diseases of the intestine. Objective In this study we developed a human PBMC–engrafted murine model of allergen-driven gut inflammation and analyzed the underlying immunologic mechanisms. Methods Nonobese diabetic (NOD)– scid -γc −/− mice were injected intraperitoneally with human PBMCs from allergic donors together with the respective allergen or not. Three weeks later, mice were challenged with the allergen orally or rectally, and gut inflammation was monitored with a high-resolution video miniendoscopic system, as well as histologically. Results Using the aeroallergens birch or gra…