Search results for "Lymphatic System"

TIE-2-expressing monocytes are lymphangiogenic and associate specifically with lymphatics of human breast cancer

2015

ABSTRACT In experimental mouse models of cancer, increasingly compelling evidence point toward a contribution of tumor associated macrophages (TAM) to tumor lymphangiogenesis. Corresponding experimental observations in human cancer remain scarce although lymphatic metastasis is widely recognized as a predominant route for tumor spread. We previously showed that, in malignant tumors of untreated breast cancer (BC) patients, TIE-2-expressing monocytes (TEM) are highly proangiogenic immunosuppressive cells and that TIE-2 and VEGFR signaling pathways drive TEM immunosuppressive function. We report here that, in human BC, TEM express the canonical lymphatic markers LYVE-1, Podoplanin, VEGFR-3 an…

Neuroblastoma patient-derived orthotopic xenografts reflect the microenvironmental hallmarks of aggressive patient tumours.

2016

AbstractTreatment of high-risk childhood neuroblastoma is a clinical challenge which has been hampered by a lack of reliable neuroblastoma mouse models for preclinical drug testing. We have previously established invasive and metastasising patient-derived orthotopic xenografts (PDXs) from high-risk neuroblastomas that retained the genotypes and phenotypes of patient tumours. Given the important role of the tumour microenvironment in tumour progression, metastasis, and treatment responses, here we analysed the tumour microenvironment of five neuroblastoma PDXs in detail. The PDXs resembled their parent tumours and retained important stromal hallmarks of aggressive lesions including rich bloo…

Plasmablastic lymphoma as a manifestation of the human immunodeficiency virus: Case report

2020

Plasmablastic lymphoma is a rare subtype of non-Hodgkin’s lymphoma, which generally presents an aggressive clinical course and low survival rates. It is strongly associated with HIV infection and the most common site of involvement of the territory of the head and neck is Waldeyer’s lymphatic ring, followed by the gastrointestinal tract, lymph nodes and skin. The morphological characteristics of PBL in the oral cavity / jaw in the context of HIV infection show diffuse sheets of large immunoblastic cells with abundant cytoplasm, vesicular chromatin and prominent nucleus, a small located in the center with plasma cells differentiation. The main goal of this article is to review the literature…

Lymphatic Endothelial Cells Control Initiation of Lymph Node Organogenesis

2017

Lymph nodes (LNs) are strategically situated throughout the body at junctures of the blood vascular and lymphatic systems to direct immune responses against antigens draining from peripheral tissues. The current paradigm describes LN development as a programmed process that is governed through the interaction between mesenchymal lymphoid tissue organizer (LTo) cells and hematopoietic lymphoid tissue inducer (LTi) cells. Using cell-type-specific ablation of key molecules involved in lymphoid organogenesis, we found that initiation of LN development is dependent on LTi-cell-mediated activation of lymphatic endothelial cells (LECs) and that engagement of mesenchymal stromal cells is a succeedi…

A conditional inducible JAK2V617F transgenic mouse model reveals myeloproliferative disease that is reversible upon switching off transgene expressio…

2019

Aberrant activation of the JAK/STAT pathway is thought to be the critical event in the pathogenesis of the chronic myeloproliferative neoplasms, polycythemia vera, essential thrombocythemia and primary myelofibrosis. The most frequent genetic alteration in these pathologies is the activating JAK2V617F mutation, and expression of the mutant gene in mouse models was shown to cause a phenotype resembling the human diseases. Given the body of genetic evidence, it has come as a sobering finding that JAK inhibitor therapy only modestly suppresses the JAK2V617F allele burden, despite showing clear benefits in terms of reducing splenomegaly and constitutional symptoms in patients. To gain a better …

Collapsibility of the internal jugular veins in the lateral decubitus body position: A potential protective role of the cerebral venous outflow again…

2019

Recent research has revealed that patients with neurodegenerative disease sleep longer in the supine position, while healthy controls prefer sleeping in the lateral decubitus position. Thus, sleeping in the lateral position seems to be protective against neurodegeneration. It has also been suggested that a protective role of this body position could be associated with better cerebral venous drainage in this body position, which results in more active glymphatic system of the brain (the system responsible for clearance of the cerebral tissue from waste products, e.g. amyloid-β). Since no published evidence exists regarding venous outflow from the cranial cavity in the lateral decubitus posit…

2019

The gut microbiota influence host vascular physiology locally in the intestine, but also evoke remote effects that impact distant organ functions. Amongst others, the microbiota affect intestinal vascular remodeling, lymphatic development, cardiac output and vascular function, myelopoiesis, prothrombotic platelet function, and immunovigilance of the host. Experimentally, host-microbiota interactions are investigated by working with animals devoid of symbiotic bacteria, i.e., by the decimation of gut commensals by antibiotic administration, or by taking advantage of germ-free mouse isolator technology. Remarkably, some of the vascular effects that were unraveled following antibiotic treatmen…

ILCs and T Cells Competing for Space: More Than a Numbers Game.

2017

T cell homeostasis critically depends on interleukin-7 (IL-7). In this issue of Immunity, Martin et al. (2017) provide evidence that IL-7 availability is regulated through a "cytokine sink" involving innate lymphoid cells that compete for and consume IL-7 and thereby restrict T cell homeostasis in lymphoid organs.

New insights into the pathogenesis of giant cell arteritis

2017

Giant cell arteritis (GCA) is an inflammatory chronic disease occurring exclusively in elderly individuals. Until recently, the disease has been considered a unique disease resulting from the interaction in the walls of susceptible arteries, between an unknown infectious agents with local dendritic cells (DCs), activated CD4 T cells and effector macrophages. Recent evidence has shown that this view was too simplistic and has clarified many of the pathogenetic aspects of the disease. Many genetic studies recently published have identified different new genes, including cytokines, adhesion molecules and regulators of innate immunity, as crucial players in the development and progression of GC…

The intestinal microbiota modulates the anticancer immune effects of cyclophosphamide

2013

The Microbiota Makes for Good Therapy The gut microbiota has been implicated in the development of some cancers, such as colorectal cancer, but—given the important role our intestinal habitants play in metabolism—they may also modulate the efficacy of certain cancer therapeutics. Iida et al. (p. 967 ) evaluated the impact of the microbiota on the efficacy of an immunotherapy [CpG (the cytosine, guanosine, phosphodiester link) oligonucleotides] and oxaliplatin, a platinum compound used as a chemotherapeutic. Both therapies were reduced in efficacy in tumor-bearing mice that lacked microbiota, with the microbiota important for activating the innate immune response against the tumors. Viaud et…