Search results for "venules"

Ectopic expression of CXCL13, BAFF, APRIL and LT-ß is associated with artery tertiary lymphoid organs in giant cell arteritis

2016

ObjectivesTo investigate whether artery tertiary lymphoid organs (ATLOs) are present in giant cell arteritis (GCA) and that their formation is associated with the ectopic expression of constitutive lymphoid tissue-homing chemokines.MethodsReverse transcriptase PCR, immunohistochemical and immunofluorescence analysis were used to determine the presence of ectopic ATLOs in GCA and the expression of chemokines/chemokine receptors and cytokines involved in lymphoneogenesis in the temporal artery samples obtained from 50 patients with GCA and 30 controls. The presence of lymphatic conduits, of follicular dendritic cells (FDCs) precursors and lymphoid tissue inducer cells was also investigated. F…

Gut Microbiota Restricts NETosis in Acute Mesenteric Ischemia-Reperfusion Injury.

2020

Objective: Recruitment of neutrophils and formation of neutrophil extracellular traps (NETs) contribute to lethality in acute mesenteric infarction. To study the impact of the gut microbiota in acute mesenteric infarction, we used gnotobiotic mouse models to investigate whether gut commensals prime the reactivity of neutrophils towards formation of neutrophil extracellular traps (NETosis). Approach and Results: We applied a mesenteric ischemia-reperfusion (I/R) injury model to germ-free (GF) and colonized C57BL/6J mice. By intravital imaging, we quantified leukocyte adherence and NET formation in I/R-injured mesenteric venules. Colonization with gut microbiota or monocolonization with Esch…

Interleukin-9 Overexpression and Th9 Polarization Characterize the Inflamed Gut, the Synovial Tissue, and the Peripheral Blood of Patients With Psori…

2016

Objective To investigate the expression and tissue distribution of Th9-related cytokines in patients with psoriatic arthritis (PsA). Methods Quantitative gene expression analysis of Th1, Th17, and Th9 cytokines was performed in intestinal biopsy samples obtained from patients with PsA, HLA-B27-positive patients with ankylosing spondylitis (AS), patients with Crohn's disease (CD), and healthy controls. Expression and tissue distribution of interleukin-23 (IL-23), IL-17, IL-22, IL-9, and IL-9 receptor (IL-9R) were evaluated by immunohistochemistry and confocal microscopy. Flow cytometry was used to study the frequency of Th9 cells among peripheral blood, lamina propria, and synovial fluid mon…

Type 3 innate lymphoid cells producing IL-17 and IL-22 are expanded in the gut, in the peripheral blood, synovial fluid and bone marrow of patients w…

2015

Background The aim of the study was to better characterise the immunological origin and the behaviour of interleukin (IL)-23-responsive innate lymphoid cells (ILCs) in the gut, synovial fluid (SF) and bone marrow (BM) of patients with ankylosing spondylitis (AS).Methods ILC1, ILC2 and ILC3 cells were determined and characterised by confocal microscopy and flow cytometry in ileal and BM biopsies, in peripheral blood (PB) and SF mononuclear cells obtained from patients with AS and controls. Mucosal vascular addressin cell adhesion molecule 1 (MADCAM-1), IL-7, IL-15 and aggregates of lymphoid tissue inducer cells (LTi) were evaluated by immunohistochemistry. The in vitro ability of epithelial …

Profile of leukocyte-endothelial cell interactions induced in venules and arterioles by nucleoside reverse-transcriptase inhibitors in vivo.

2013

Background There is controversy regarding cardiovascular (CV) toxicity of the nucleoside reverse-transcriptase inhibitors used to treat human immunodeficiency virus infection. Methods We evaluated the effects of nucleoside reverse-transcriptase inhibitors on leukocyte-endothelium interactions, a hallmark of CV diseases, in rat mesenteric vessels using intravital microscopy and in human arterial cells using a flow chamber system. Results Abacavir and didanosine increased rolling, adhesion and emigration in rat vessels. These effects were reversed with antibodies against Macrophage-1 antigen (Mac-1) or intercellular adhesion molecule 1 and were reproduced in human cells. Lamivudine, zidovudin…

Angioimmunoblastic T-cell lymphoma

2008

Angioimmunoblastic T-cell lymphoma (AITL) is a rare and aggressive neoplasm clinically characterized by sudden onset of constitutional symptoms, lymphadenopathy, hepatosplenomegaly, frequent autoimmune phenomena, particularly hemolytic anemia and thrombocytopenia, and polyclonal hypergammaglobulinemia. The lymph node histological picture is also distinctive, constituted by a polymorphic infiltrate, a marked proliferation of high endothelial venules, and a dense meshwork of dentritic cells. The neoplastic CD4+ T-cells represent a minority of the lymph node cell population; its detection is facilitated by the aberrant expression of CD10. Almost all cases arbor an EBV infected B-cell populatio…

SAT0023 Artery Tertiary Lymphoid Organs Occur in Giant Cell Arteritis

2016

Background Arteries are immuno-privileged sites. In advanced atherosclerotic lesions, however, adventitial lymphoid infiltrates, sometimes aggregated in lymphoid follicles (the so called artery tertiary lymphoid organs, ATLO), occur together with marked neoangiogenesis and lymphangiogenesis, and with the extensive induction of high endothelial venules. Objectives To investigate if tertiary lymphoid organs (TLO) are present in GCA and their formation is associated with the ectopic expression of constitutive lymphoid tissue-homing chemokines. Methods RT-PCR, immunohistochemical and immunofluorescence analysis were used to determine the presence of ectopic TLO in GCA and the expression of chem…

New route of lymphocyte diapedesis through High endothelial venules (HEVs) in peripheral and mucosa-associated lymphoid tissue

2009

L-NAME induces direct arteriolar leukocyte adhesion, which is mainly mediated by angiotensin-II.

2005

Acute inhibition (1 h) of nitric oxide synthase (NOS) with L-NAME causes leukocyte recruitment in the rat mesenteric postcapillary venules that is angiotensin-II (Ang-II) dependent. Since 4-h exposure to Ang-II provokes arteriolar leukocyte adhesion, this study was designed to investigate whether subacute (4-h) NOS inhibition also causes this effect.Rats were intraperitoneally injected with saline, L-NAME, or 1H-[1,2,4]-oxidazolol-[4,3-a]-quinoxalin-1-one (ODQ). Leukocyte accumulation in the mesenteric microcirculation was examined 4 h later via intravital microscopy. Some groups were pretreated with losartan, an AT(1) Ang-II receptor antagonist.At 4-h, L-NAME caused a significant increase …

Arterial and Venous Endothelia Display Differential Functional Fractalkine (CX 3 CL1) Expression by Angiotensin-II

2012

Objective— Angiotensin-II (Ang-II) promotes the interaction of mononuclear cells with arterioles and neutrophils with postcapillary venules. To investigate the mechanisms underlying this dissimilar response, the involvement of fractalkine (CX 3 CL1) was explored. Methods and Results— Enhanced CX 3 CL1 expression was detected in both cremasteric arterioles and postcapillary venules 24 hours after Ang-II intrascrotal injection. Arteriolar leukocyte adhesion was the unique parameter significantly reduced (83%) in animals lacking CX 3 CL1 receptor (CX 3 CR1). Human umbilical arterial and venous endothelial cell stimulation with 1 μmol/L Ang-II increased CX 3 CL1 expression, yet neutralization …