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Sample records for afferent lymphatic vessels

  1. Interleukin-7 is produced by afferent lymphatic vessels and supports lymphatic drainage

    PubMed Central

    Iolyeva, Maria; Aebischer, David; Proulx, Steven T.; Willrodt, Ann-Helen; Ecoiffier, Tatiana; Häner, Simone; Bouchaud, Grégory; Krieg, Carsten; Onder, Lucas; Ludewig, Burkhard; Santambrogio, Laura; Boyman, Onur; Chen, Lu; Finke, Daniela

    2013-01-01

    The cytokine interleukin (IL)-7 exerts essential roles in lymph node (LN) organogenesis and lymphocyte development and homeostasis. Recent studies have identified lymphatic endothelial cells (LECs) as a major source of IL-7 in LNs. Here, we report that LECs not only produce IL-7, but also express the IL-7 receptor chains IL-7Rα and CD132. Stimulation with recombinant IL-7 enhanced LEC in vitro activity and induced lymphangiogenesis in the cornea of wild-type (WT) mice. Whereas in IL-7Rα−/− mice, dermal lymphatic vessels (LVs) were abnormally organized and lymphatic drainage was compromised, transgenic overexpression of IL-7 in mice resulted in an expanded dermal LV network with increased drainage function. Moreover, systemic treatment with recombinant IL-7 enhanced lymphatic drainage in the skin of WT mice and of mice devoid of lymphocytes. Experiments in IL-7Rα−/− bone marrow chimeras demonstrated that the drainage-enhancing activity of IL-7 was exclusively dependent on IL-7Rα expression in stromal but not in hematopoietic cells. Finally, near-infrared in vivo imaging performed in IL-7Rα−/− mice revealed that the pumping activity of collecting vessels was normal but fluid uptake into lymphatic capillaries was defective. Overall, our data point toward an unexpected new role for IL-7 as a potential autocrine mediator of lymphatic drainage. PMID:23963040

  2. Initial Afferent Lymphatic Vessels Controlling Outbound Leukocyte Traffic from Skin to Lymph Nodes

    PubMed Central

    Teijeira, Alvaro; Rouzaut, Ana; Melero, Ignacio

    2013-01-01

    Tissue drains fluid and macromolecules through lymphatic vessels (LVs), which are lined by a specialized endothelium that expresses peculiar differentiation proteins, not found in blood vessels (i.e., LYVE-1, Podoplanin, PROX-1, and VEGFR-3). Lymphatic capillaries are characteristically devoid of a continuous basal membrane and are anchored to the ECM by elastic fibers that act as pulling ropes which open the vessel to avoid edema if tissue volume increases, as it occurs upon inflammation. LVs are also crucial for the transit of T lymphocytes and antigen presenting cells from tissue to draining lymph nodes (LN). Importantly, cell traffic control across lymphatic endothelium is differently regulated under resting and inflammatory conditions. Under steady-state non-inflammatory conditions, leukocytes enter into the lymphatic capillaries through basal membrane gaps (portals). This entrance is integrin-independent and seems to be mainly guided by CCL21 chemokine gradients acting on leukocytes expressing CCR7. In contrast, inflammatory processes in lymphatic capillaries involve a plethora of cytokines, chemokines, leukocyte integrins, and other adhesion molecules. Importantly, under inflammation a role for integrins and their ligands becomes apparent and, as a consequence, the number of leukocytes entering the lymphatic capillaries multiplies several-fold. Enhancing transmigration of dendritic cells en route to LN is conceivably useful for vaccination and cancer immunotherapy, whereas interference with such key mechanisms may ameliorate autoimmunity or excessive inflammation. Recent findings illustrate how, transient cell-to-cell interactions between lymphatic endothelial cells and leukocytes contribute to shape the subsequent behavior of leukocytes and condition the LV for subsequent trans-migratory events. PMID:24368908

  3. A High-Salt Diet Differentially Modulates Mechanical Activity of Afferent and Efferent Collecting Lymphatics in Murine Iliac Lymph Nodes

    PubMed Central

    Mizuno, Risuke; Ono, Nobuyuki; Nishimoto, Mitsuhiro; Fujita, Toshiro

    2015-01-01

    Abstract Background: The lymphatic system contributes to fluid homeostasis in various tissues. Recent evidence suggests that lymphangiogenesis induced by a high-salt diet (HSD) is associated with blood pressure regulation. Lymph nodes, located along lymphatic pathways, are not only important secondary lymphoid tissues for cancer metastasis, inflammation, and immune responses, but are also important for fluid homeostasis. Afferent lymphatics collect lymph from the pre-nodal area and efferent lymphatics drain lymph out of the lymph nodes. However, the difference in mechanical activity between afferent and efferent lymphatics and the effect of a HSD on these vessels have not been shown. Methods and Results: Changes in mechanical activity of isolated afferent and efferent lymphatics in normal salt diet (NSD) and 4-week HSD mice in response to increases in intraluminal pressures from 3 to 7 cmH2O were measured using video-microscopy. The higher intramural pressure equivalently decreased pumping activity of afferent and efferent lymphatics in NSD mice. A HSD suppressed the amplitude, ejection fraction, and stroke volume of afferent lymphatics, leading to marked reductions in pumping activity. In contrast, the pumping activities of efferent lymphatics were resistant to a HSD and were preserved by enhancing the contraction frequency. Conclusions: A HSD differentially modulated the mechanical activity of afferent and efferent collecting lymphatics in murine iliac lymph nodes. PMID:26091404

  4. Blood and lymphatic vessel formation.

    PubMed

    Bautch, Victoria L; Caron, Kathleen M

    2015-03-02

    Blood and lymphatic vessels deliver oxygen and nutrients, remove waste and CO2, and regulate interstitial pressure in tissues and organs. These vessels begin life early in embryogenesis using transcription factors and signaling pathways that regulate differentiation, morphogenesis, and proliferation. Here we describe how these vessels develop in the mouse embryo, and the signals that are important to their development.

  5. lyve1 expression reveals novel lymphatic vessels and new mechanisms for lymphatic vessel development in zebrafish.

    PubMed

    Okuda, Kazuhide S; Astin, Jonathan W; Misa, June P; Flores, Maria V; Crosier, Kathryn E; Crosier, Philip S

    2012-07-01

    We have generated novel transgenic lines that brightly mark the lymphatic system of zebrafish using the lyve1 promoter. Facilitated by these new transgenic lines, we generated a map of zebrafish lymphatic development up to 15 days post-fertilisation and discovered three previously uncharacterised lymphatic vessel networks: the facial lymphatics, the lateral lymphatics and the intestinal lymphatics. We show that a facial lymphatic vessel, termed the lateral facial lymphatic, develops through a novel developmental mechanism, which initially involves vessel growth through a single vascular sprout followed by the recruitment of lymphangioblasts to the vascular tip. Unlike the lymphangioblasts that form the thoracic duct, the lymphangioblasts that contribute to the lateral facial lymphatic vessel originate from a number of different blood vessels. Our work highlights the additional complexity of lymphatic vessel development in the zebrafish that may increase its versatility as a model of lymphangiogenesis.

  6. Treg engage lymphotoxin beta receptor for afferent lymphatic transendothelial migration

    PubMed Central

    Brinkman, C. Colin; Iwami, Daiki; Hritzo, Molly K.; Xiong, Yanbao; Ahmad, Sarwat; Simon, Thomas; Hippen, Keli L.; Blazar, Bruce R.; Bromberg, Jonathan S.

    2016-01-01

    Regulatory T cells (Tregs) are essential to suppress unwanted immunity or inflammation. After islet allo-transplant Tregs must migrate from blood to allograft, then via afferent lymphatics to draining LN to protect allografts. Here we show that Tregs but not non-Treg T cells use lymphotoxin (LT) during migration from allograft to draining LN, and that LT deficiency or blockade prevents normal migration and allograft protection. Treg LTαβ rapidly modulates cytoskeletal and membrane structure of lymphatic endothelial cells; dependent on VCAM-1 and non-canonical NFκB signalling via LTβR. These results demonstrate a form of T-cell migration used only by Treg in tissues that serves an important role in their suppressive function and is a unique therapeutic focus for modulating suppression. PMID:27323847

  7. [Morphogenesis, structure and properties of lymphatic vessels].

    PubMed

    Ratajska, Anna; Jankowska-Steifer, Ewa; Czarnowska, Elżbieta; Flaht, Aleksandra; Radomska-Leśniewska, Dorota

    2012-11-19

    In this paper, we present literature results related to structure and various manners of lymphatic vessel formation during embryonic development and in pathological events, such as tumorigenesis, wound healing, and other diseases. The functions of the lymphatic system include the collection of fluids that enter tissues from the circulation, absorption of lipids and lipid-soluble vitamins from the intestine and their subsequent transport, participation in antigen, dendritic cell, and lymphocyte migration. The lymphatic system is also a route for tumor cell and inflammatory cell transport. Native lymphatic capillaries differ from blood capillaries by having an irregular lumen, a discontinuous basement membrane, absence of pericytes, and a strong anchorage of their endothelial cells to the extracellular matrix via microfibrils built of emilin and fibrillin. Lymphatic endothelial cells express surface antigens such as Lyve-1, podoplanin, VEGFR3 (Flk4) and transcription factor Prox-1, as well as molecules which are common for blood endothelial cells and lymphatic endothelial cells (CD31, CD34, Flk-1, Tie-1, Tie-2, neuropilin 2). Lymphatic vessel formation during embryonic development starts with the occurrence of lymphatic sacs sprouting from systemic jugular veins and/or by co-option of lymphangioblasts or hematopoietic-derived cells. It can also proceed by dedifferentiation of venous endothelial cells after their detachment from the venous system, migration to the target places within the body and assembly in the lymphatic lumen. Mechanisms of lymphatic vessel formation during embryonic development and in pathological conditions, such as tumorigenesis, wound healing, and metastasis, is regulated by a plethora of growth factors and molecules, among which the most important are VEGF-C, VEGF-D, HGF, FGF, retinoic acid, IL-3, and IL-7. Macrophages and cells bearing CD45 phenotype seem to take part in the formation of lymphatics. Macrophages might act as a source of growth

  8. Organization and developmental aspects of lymphatic vessels.

    PubMed

    Ohtani, Osamu; Ohtani, Yuko

    2008-05-01

    The lymphatic system plays important roles in maintaining tissue fluid homeostasis, immune surveillance of the body, and the taking up dietary fat and fat-soluble vitamins A, D, E and K. The lymphatic system is involved in many pathological conditions, including lymphedema, inflammatory diseases, and tumor dissemination. A clear understanding of the organization of the lymphatic vessels in normal conditions would be critically important to develop new treatments for diseases involving the lymphatic vascular system. Therefore, the present paper reviews the organization of the lymphatic vascular system of a variety of organs, including the thyroid gland, lung and pleura, small intestine, cecum and colon in the rat, the diaphragm in the rat, monkey, and human, Peyer's patches and the appendix in the rabbit, and human tonsils. Methods employed include scanning electron microscopy of lymphatic corrosion casts and tissues with or without treatment of alkali maceration technique, transmission electron microscopy of intact tissues, confocal microscopy in conjunction with immunohistochemistry to some lymphatic-specific markers (i.e., LYVE-1 and VEGFR-3), and light microscopy in conjunction with enzyme-histochemistry to 5'-nucleotidase. Some developmental aspects of the lymphatic vessels and lymphedema are also discussed.

  9. Connexins in lymphatic vessel physiology and disease.

    PubMed

    Meens, Merlijn J; Sabine, Amélie; Petrova, Tatiana V; Kwak, Brenda R

    2014-04-17

    Connexins are transmembrane proteins that form gap junction- and hemi-channels. Once inserted into the membrane, hemi-channels (connexons) allow for diffusion of ions and small molecules (<1 kDa) between the extracellular space and the cytosol. Gap junction channels allow diffusion of similar molecules between the cytoplasms of adjacent cells. The expression and function of connexins in blood vessels has been intensely studied in the last few decades. In contrast, only a few studies paid attention to lymphatic vessels; convincing in vivo data with respect to expression patterns of lymphatic connexins and their functional roles have only recently begun to emerge. Interestingly, mutations in connexin genes have been linked to diseases of lymphatic vasculature, most notably primary and secondary lymphedema. This review summarizes the available data regarding lymphatic connexins. More specifically it addresses (i) early studies aimed at presence of gap junction-like structures in lymphatic vessels, (ii) more recent studies focusing on lymphatic connexins using genetically engineered mice, and (iii) results of clinical studies that have reported lymphedema-linked mutations in connexin genes.

  10. Imaging blood vessels and lymphatic vessels in the zebrafish.

    PubMed

    Jung, H M; Isogai, S; Kamei, M; Castranova, D; Gore, A V; Weinstein, B M

    2016-01-01

    Blood vessels supply tissues and organs with oxygen, nutrients, cellular, and humoral factors, while lymphatic vessels regulate tissue fluid homeostasis, immune trafficking, and dietary fat absorption. Understanding the mechanisms of vascular morphogenesis has become a subject of intense clinical interest because of the close association of both types of vessels with pathogenesis of a broad spectrum of human diseases. The zebrafish provides a powerful animal model to study vascular morphogenesis because of their small, accessible, and transparent embryos. These unique features of zebrafish embryos permit sophisticated high-resolution live imaging of even deeply localized vessels during embryonic development and even in adult tissues. In this chapter, we summarize various methods for blood and lymphatic vessel imaging in zebrafish, including nonvital resin injection-based or dye injection-based vessel visualization, and alkaline phosphatase staining. We also provide protocols for vital imaging of vessels using microangiography or transgenic fluorescent reporter zebrafish lines. PMID:27263409

  11. Interactions of immune cells and lymphatic vessels.

    PubMed

    Kataru, Raghu P; Lee, Yulia G; Koh, Gou Young

    2014-01-01

    In addition to fluid and lipid absorption, immune cell trafficking has now become recognized as one of the major functions of the lymphatic system. Recently, several critical roles of the lymphatic vessels (LVs) in modulating immune reactions during both physiological and pathological conditions have been emerging. As LVs serve as conduits for immune cells, they come to closely interact with macrophages/monocytes, dendritic cells, and T and B lymphocytes. Accumulating evidences indicate that reciprocal interactions between the LVs and immune cells exist which cause considerable influence over the process of immune cell migration, LV growth, and ultimately certain immune reactions. This chapter discusses on the interactions of macrophages/monocytes and dendritic cells with peripheral LVs and on those of sinusoidal macrophages and T and B lymphocytes with lymph node LVs.

  12. Comparison of approaches for microscopic imaging of skin lymphatic vessels.

    PubMed

    Wu, Xiufeng; Yu, Zheyuan; Liu, Ningfei

    2012-01-01

    Assessment of skin lymphatic vessels is of great significance in understanding their roles in many pathological conditions. Our aim was to identify the optimal approach for investigation of cutaneous lymphatic system. We performed comparative studies on skin lymphatic vessels using immunohistochemistry of tissue sections, computer graphic reconstruction method together with immunohistochemically stained serial sections and whole mount fluorescence in human lower limb. Lymphatic vessels were identified with podoplanin antibody. The relative merits and drawbacks of each method in evaluation of structure, spatial organization, and distribution of cutaneous lymphatic vessels were described. Immunohistology of tissue sections enabled the investigation of the structure and distribution of the whole cutaneous lymphatic system in two-dimensional slices, whereas three-dimensional morphology of only the most superficial lymph capillary network immediately under the epidermis could be evaluated with the whole mount technique. Meanwhile, only little segmentation of skin lymphatic vessel from five immunohistochemically stained serial sections was reconstructed and evaluated due to expense and special skills required using computer graphic three-dimensional reconstruction. Furthermore, a great number of artifacts and special skills required in its processes leaded to less accurate structure of skin lymphatic vessels. Our findings demonstrated that the use of either of the proposed techniques alone could not allow a comprehensive analysis of the skin lymphatic system due to their relative drawbacks. Combination of immunohistology of tissue sections and three-dimensional whole-mount preparations appears to be the best candidate for comprehensive evaluation of skin lymphatic system.

  13. Lymph flow regulates collecting lymphatic vessel maturation in vivo.

    PubMed

    Sweet, Daniel T; Jiménez, Juan M; Chang, Jeremy; Hess, Paul R; Mericko-Ishizuka, Patricia; Fu, Jianxin; Xia, Lijun; Davies, Peter F; Kahn, Mark L

    2015-08-01

    Fluid shear forces have established roles in blood vascular development and function, but whether such forces similarly influence the low-flow lymphatic system is unknown. It has been difficult to test the contribution of fluid forces in vivo because mechanical or genetic perturbations that alter flow often have direct effects on vessel growth. Here, we investigated the functional role of flow in lymphatic vessel development using mice deficient for the platelet-specific receptor C-type lectin-like receptor 2 (CLEC2) as blood backfills the lymphatic network and blocks lymph flow in these animals. CLEC2-deficient animals exhibited normal growth of the primary mesenteric lymphatic plexus but failed to form valves in these vessels or remodel them into a structured, hierarchical network. Smooth muscle cell coverage (SMC coverage) of CLEC2-deficient lymphatic vessels was both premature and excessive, a phenotype identical to that observed with loss of the lymphatic endothelial transcription factor FOXC2. In vitro evaluation of lymphatic endothelial cells (LECs) revealed that low, reversing shear stress is sufficient to induce expression of genes required for lymphatic valve development and identified GATA2 as an upstream transcriptional regulator of FOXC2 and the lymphatic valve genetic program. These studies reveal that lymph flow initiates and regulates many of the key steps in collecting lymphatic vessel maturation and development.

  14. Visualization of lymphatic vessel development, growth, and function.

    PubMed

    Pollmann, Cathrin; Hägerling, René; Kiefer, Friedemann

    2014-01-01

    Despite their important physiological and pathophysiological functions, lymphatic endothelial cells and lymphatic vessels remain less well studied compared to the blood vascular system. Lymphatic endothelium differentiates from venous blood vascular endothelium after initial arteriovenous differentiation. Only recently by the use of light sheet microscopy, the precise mechanism of separation of the first lymphatic endothelial progenitors from the cardinal vein has been described as delamination followed by mesenchymal cell migration of lymphatic endothelial cells. Dorsolaterally of the embryonic cardinal vein, lymphatic endothelial cells reaggregate to form the first lumenized lymphatic vessels, the dorsal peripheral longitudinal vessel and the more ventrally positioned primordial thoracic duct. Despite this progress in our understanding of the first lymph vessel formation, intravital observation of lymphatic vessel behavior in the intact organism, during development and in the adult, is prerequisite to a precise understanding of this tissue. Transgenic models and two-photon microscopy, in combination with optical windows, have made live intravital imaging possible: however, new imaging modalities and novel approaches promise gentler, more physiological, and longer intravital imaging of lymphatic vessels.

  15. Lymphatic vessels: new targets for the treatment of inflammatory diseases.

    PubMed

    Dieterich, Lothar C; Seidel, Catharina D; Detmar, Michael

    2014-04-01

    The lymphatic system plays an important role in the physiological control of the tissue fluid balance and in the initiation of immune responses. Recent studies have shown that lymphangiogenesis, the growth of new lymphatic vessels and/or the expansion of existing lymphatic vessels, is a characteristic feature of acute inflammatory reactions and of chronic inflammatory diseases. In these conditions, lymphatic vessel expansion occurs at the tissue level but also within the draining lymph nodes. Surprisingly, activation of lymphatic vessel function by delivery of vascular endothelial growth factor-C exerts anti-inflammatory effects in several models of cutaneous and joint inflammation. These effects are likely mediated by enhanced drainage of extravasated fluid and inflammatory cells, but also by lymphatic vessel-mediated modulation of immune responses. Although some of the underlying mechanisms are just beginning to be identified, lymphatic vessels have emerged as important targets for the development of new therapeutic strategies to treat inflammatory conditions. In this context, it is of great interest that some of the currently used anti-inflammatory drugs also potently activate lymphatic vessels.

  16. How Do Meningeal Lymphatic Vessels Drain the CNS?

    PubMed

    Raper, Daniel; Louveau, Antoine; Kipnis, Jonathan

    2016-09-01

    The many interactions between the nervous and the immune systems, which are active in both physiological and pathological states, have recently become more clearly delineated with the discovery of a meningeal lymphatic system capable of carrying fluid, immune cells, and macromolecules from the central nervous system (CNS) to the draining deep cervical lymph nodes. However, the exact localization of the meningeal lymphatic vasculature and the path of drainage from the cerebrospinal fluid (CSF) to the lymphatics remain poorly understood. Here, we discuss the potential differences between peripheral and CNS lymphatic vessels and examine the purported mechanisms of CNS lymphatic drainage, along with how these may fit into established patterns of CSF flow.

  17. An overview of lymphatic vessels and their emerging role in cardiovascular disease.

    PubMed

    Jones, Dennis; Min, Wang

    2011-07-01

    Over the past decade, molecular details of lymphatic vessels (lymphatics) have been rapidly acquired due to the identification of lymphatic endothelial-specific markers. Separate from the cardiovascular system, the lymphatic system is also an elaborate network of vessels that are important in normal physiology. Lymphatic vessels have the unique task to regulate fluid homeostasis, assist in immune surveillance, and transport dietary lipids. However, dysfunctional lymphatic vessels can cause pathology, while normal lymphatics can exacerbate pathology. This review summarizes the development and growth of lymphatic vessels in addition to highlighting their critical roles in physiology and pathology. Also, we discuss recent work that suggests a connection between lymphatic dysfunction and cardiovascular disease.

  18. Lymphovenous hemostasis and the role of platelets in regulating lymphatic flow and lymphatic vessel maturation.

    PubMed

    Welsh, John D; Kahn, Mark L; Sweet, Daniel T

    2016-09-01

    Aside from the established role for platelets in regulating hemostasis and thrombosis, recent research has revealed a discrete role for platelets in the separation of the blood and lymphatic vascular systems. Platelets are activated by interaction with lymphatic endothelial cells at the lymphovenous junction, the site in the body where the lymphatic system drains into the blood vascular system, resulting in a platelet plug that, with the lymphovenous valve, prevents blood from entering the lymphatic circulation. This process, known as "lymphovenous hemostasis," is mediated by activation of platelet CLEC-2 receptors by the transmembrane ligand podoplanin expressed by lymphatic endothelial cells. Lymphovenous hemostasis is required for normal lymph flow, and mice deficient in lymphovenous hemostasis exhibit lymphedema and sometimes chylothorax phenotypes indicative of lymphatic insufficiency. Unexpectedly, the loss of lymph flow in these mice causes defects in maturation of collecting lymphatic vessels and lymphatic valve formation, uncovering an important role for fluid flow in driving endothelial cell signaling during development of collecting lymphatics. This article summarizes the current understanding of lymphovenous hemostasis and its effect on lymphatic vessel maturation and synthesizes the outstanding questions in the field, with relationship to human disease. PMID:27385789

  19. Lymphatic Vessels, Inflammation, and Immunity in Skin Cancer

    PubMed Central

    Lund, Amanda W.; Medler, Terry R.; Leachman, Sancy A.; Coussens, Lisa M.

    2015-01-01

    Skin is a highly ordered immune organ that coordinates rapid responses to external insult while maintaining self-tolerance. In healthy tissue, lymphatic vessels drain fluid and coordinate local immune responses; however, environmental factors induce lymphatic vessel dysfunction, leading to lymph stasis and perturbed regional immunity. These same environmental factors drive the formation of local malignancies, which are also influenced by local inflammation. Herein, we discuss clinical and experimental evidence supporting the tenet that lymphatic vessels participate in regulation of cutaneous inflammation and immunity, are important contributors to malignancy and potential biomarkers and targets for immunotherapy. PMID:26552413

  20. Lymphatic vessel development: fluid flow and valve-forming cells.

    PubMed

    Kume, Tsutomu

    2015-08-01

    Hemodynamic forces regulate many aspects of blood vessel disease and development, including susceptibility to atherosclerosis and remodeling of primary blood vessels into a mature vascular network. Vessels of the lymphatic circulatory system are also subjected to fluid flow-associated forces, but the molecular and cellular mechanisms by which these forces regulate the formation and maintenance of lymphatic vessels remain largely uncharacterized. This issue of the JCI includes two articles that begin to address how fluid flow influences lymphatic vessel development and function. Sweet et al. demonstrate that lymph flow is essential for the remodeling of primary lymphatic vessels, for ensuring the proper distribution of smooth muscle cells (SMCs), and for the development and maturation of lymphatic valves. Kazenwadel et al. show that flow-induced lymphatic valve development is initiated by the upregulation of GATA2, which has been linked to lymphedema in patients with Emberger syndrome. Together, these observations and future studies inspired by these results have potential to lead to the development of strategies for the treatment of lymphatic disorders.

  1. Lymphangion coordination minimally affects mean flow in lymphatic vessels.

    PubMed

    Venugopal, Arun M; Stewart, Randolph H; Laine, Glen A; Dongaonkar, Ranjeet M; Quick, Christopher M

    2007-08-01

    The lymphatic system returns interstitial fluid to the central venous circulation, in part, by the cyclical contraction of a series of "lymphangion pumps" in a lymphatic vessel. The dynamics of individual lymphangions have been well characterized in vitro; their frequencies and strengths of contraction are sensitive to both preload and afterload. However, lymphangion interaction within a lymphatic vessel has been poorly characterized because it is difficult to experimentally alter properties of individual lymphangions and because the afterload of one lymphangion is coupled to the preload of another. To determine the effects of lymphangion interaction on lymph flow, we adapted an existing mathematical model of a lymphangion (characterizing lymphangion contractility, lymph viscosity, and inertia) to create a new lymphatic vessel model consisting of several lymphangions in series. The lymphatic vessel model was validated with focused experiments on bovine mesenteric lymphatic vessels in vitro. The model was then used to predict changes in lymph flow with different time delays between onset of contraction of adjacent lymphangions (coordinated case) and with different relative lymphangion contraction frequencies (noncoordinated case). Coordination of contraction had little impact on mean flow. Furthermore, orthograde and retrograde propagations of contractile waves had similar effects on flow. Model results explain why neither retrograde propagation of contractile waves nor the lack of electrical continuity between lymphangions adversely impacts flow. Because lymphangion coordination minimally affects mean flow in lymphatic vessels, lymphangions have flexibility to independently adapt to local conditions.

  2. Consensus statement on the immunohistochemical detection of ocular lymphatic vessels.

    PubMed

    Schroedl, Falk; Kaser-Eichberger, Alexandra; Schlereth, Simona L; Bock, Felix; Regenfuss, Birgit; Reitsamer, Herbert A; Lutty, Gerard A; Maruyama, Kazuichi; Chen, Lu; Lütjen-Drecoll, Elke; Dana, Reza; Kerjaschki, Dontscho; Alitalo, Kari; De Stefano, Maria Egle; Junghans, Barbara M; Heindl, Ludwig M; Cursiefen, Claus

    2014-10-01

    There is currently considerable controversy about existence and classification of "lymphatic vessels" in the eye. Some of the confusion is certainly caused by inappropriate use (or nonuse) of the correct immunohistochemical markers. Many experts in the field expressed the need for a consensus statement, and, in this perspective, authors offer arguments and solutions to reliably continue with immunohistochemical ocular lymphatic research.

  3. Rapid Lymphatic Dissemination of Encapsulated Group A Streptococci via Lymphatic Vessel Endothelial Receptor-1 Interaction.

    PubMed

    Lynskey, Nicola N; Banerji, Suneale; Johnson, Louise A; Holder, Kayla A; Reglinski, Mark; Wing, Peter A C; Rigby, David; Jackson, David G; Sriskandan, Shiranee

    2015-09-01

    The host lymphatic network represents an important conduit for pathogen dissemination. Indeed, the lethal human pathogen group A streptococcus has a predilection to induce pathology in the lymphatic system and draining lymph nodes, however the underlying basis and subsequent consequences for disease outcome are currently unknown. Here we report that the hyaluronan capsule of group A streptococci is a crucial virulence determinant for lymphatic tropism in vivo, and further, we identify the lymphatic vessel endothelial receptor-1 as the critical host receptor for capsular hyaluronan in the lymphatic system. Interference with this interaction in vivo impeded bacterial dissemination to local draining lymph nodes and, in the case of a hyper-encapsulated M18 strain, redirected streptococcal entry into the blood circulation, suggesting a pivotal role in the manifestation of streptococcal infections. Our results reveal a novel function for bacterial capsular polysaccharide in directing lymphatic tropism, with potential implications for disease pathology.

  4. Rapid Lymphatic Dissemination of Encapsulated Group A Streptococci via Lymphatic Vessel Endothelial Receptor-1 Interaction

    PubMed Central

    Johnson, Louise A.; Holder, Kayla A.; Reglinski, Mark; Wing, Peter A. C.; Rigby, David; Jackson, David G.; Sriskandan, Shiranee

    2015-01-01

    The host lymphatic network represents an important conduit for pathogen dissemination. Indeed, the lethal human pathogen group A streptococcus has a predilection to induce pathology in the lymphatic system and draining lymph nodes, however the underlying basis and subsequent consequences for disease outcome are currently unknown. Here we report that the hyaluronan capsule of group A streptococci is a crucial virulence determinant for lymphatic tropism in vivo, and further, we identify the lymphatic vessel endothelial receptor-1 as the critical host receptor for capsular hyaluronan in the lymphatic system. Interference with this interaction in vivo impeded bacterial dissemination to local draining lymph nodes and, in the case of a hyper-encapsulated M18 strain, redirected streptococcal entry into the blood circulation, suggesting a pivotal role in the manifestation of streptococcal infections. Our results reveal a novel function for bacterial capsular polysaccharide in directing lymphatic tropism, with potential implications for disease pathology. PMID:26352587

  5. Lymphatic vessels arise from specialized angioblasts within a venous niche.

    PubMed

    Nicenboim, J; Malkinson, G; Lupo, T; Asaf, L; Sela, Y; Mayseless, O; Gibbs-Bar, L; Senderovich, N; Hashimshony, T; Shin, M; Jerafi-Vider, A; Avraham-Davidi, I; Krupalnik, V; Hofi, R; Almog, G; Astin, J W; Golani, O; Ben-Dor, S; Crosier, P S; Herzog, W; Lawson, N D; Hanna, J H; Yanai, I; Yaniv, K

    2015-06-01

    How cells acquire their fate is a fundamental question in developmental and regenerative biology. Multipotent progenitors undergo cell-fate restriction in response to cues from the microenvironment, the nature of which is poorly understood. In the case of the lymphatic system, venous cells from the cardinal vein are thought to generate lymphatic vessels through trans-differentiation. Here we show that in zebrafish, lymphatic progenitors arise from a previously uncharacterized niche of specialized angioblasts within the cardinal vein, which also generates arterial and venous fates. We further identify Wnt5b as a novel lymphatic inductive signal and show that it also promotes the ‘angioblast-to-lymphatic’ transition in human embryonic stem cells, suggesting that this process is evolutionarily conserved. Our results uncover a novel mechanism of lymphatic specification, and provide the first characterization of the lymphatic inductive niche. More broadly, our findings highlight the cardinal vein as a heterogeneous structure, analogous to the haematopoietic niche in the aortic floor.

  6. Lymphatic vessels in the developing diaphragm of the rat.

    PubMed

    Poggi, P; Marchetti, C; Calligaro, A; Casasco, A; Scelsi, R

    1991-01-01

    Diaphragms of fetal, neonatal and young albino rats have been observed both under light and electron microscopes to examine the presence and distribution of lymphatic vessels and their morphological features. In fetal diaphragms of between 18 and 22 days of gestation, no normal lymphatic vessels can be seen; only after birth, specifically in neonatal and 2-day-old rats, small lymphatic vessels appear; they are in close proximity to the blood vessels in the inner areas of the muscle. As the rats get older, lymphatic vessels are also observed in the subserosa where an abundant connective tissue is present. The fine structure of diaphragmatic lymphatic vessels is different at different ages. In neonatal rats of up to 2 days, the endothelial wall is very thin and often holed. The relationships between contiguous endothelial cells are characterized by simple end-to-end or overlapping structures. The basement membrane is virtually absent. Within the first week of life, the endothelial wall becomes more complex; along the wall, complex interdigitations between two contiguous endothelial cells often touch. A discontinuous basement membrane and collagen and elastic fibers surround the vessels. In the older rats (from 14 to 25 to 140 days), next to the complex interdigitations which characterize the junction between two contiguous endothelial cells, cellular flaps interdigitate forming a channel which opens out either to the exterior or the interior of the vessel. Dense bundles of elastic and collagen fibers are closely apposed to the endothelial wall.

  7. Lymphatic vessels regulate immune microenvironments in human and murine melanoma.

    PubMed

    Lund, Amanda W; Wagner, Marek; Fankhauser, Manuel; Steinskog, Eli S; Broggi, Maria A; Spranger, Stefani; Gajewski, Thomas F; Alitalo, Kari; Eikesdal, Hans P; Wiig, Helge; Swartz, Melody A

    2016-09-01

    Lymphatic remodeling in tumor microenvironments correlates with progression and metastasis, and local lymphatic vessels play complex and poorly understood roles in tumor immunity. Tumor lymphangiogenesis is associated with increased immune suppression, yet lymphatic vessels are required for fluid drainage and immune cell trafficking to lymph nodes, where adaptive immune responses are mounted. Here, we examined the contribution of lymphatic drainage to tumor inflammation and immunity using a mouse model that lacks dermal lymphatic vessels (K14-VEGFR3-Ig mice). Melanomas implanted in these mice grew robustly, but exhibited drastically reduced cytokine expression and leukocyte infiltration compared with those implanted in control animals. In the absence of local immune suppression, transferred cytotoxic T cells more effectively controlled tumors in K14-VEGFR3-Ig mice than in control mice. Furthermore, gene expression analysis of human melanoma samples revealed that patient immune parameters are markedly stratified by levels of lymphatic markers. This work suggests that the establishment of tumor-associated inflammation and immunity critically depends on lymphatic vessel remodeling and drainage. Moreover, these results have implications for immunotherapies, the efficacies of which are regulated by the tumor immune microenvironment. PMID:27525437

  8. The association of adult Onchocerca volvulus with lymphatic vessels.

    PubMed

    Mackenzie, C D; Huntington, M K; Wanji, S; Lovato, R V; Eversole, R R; Geary, T G

    2010-02-01

    Immunocytochemical examination of onchocercal nodule tissues containing adult Onchocerca volvulus using immuno-markers for blood and lymphatic vessels (vWF, D2-40, podoplanin, Prox-1, and Lyve1) shows a distinct pattern of distribution of these vessels within nodules. Blood vessels were commonly seen associated with organized lymphoid cellular aggregates in the both the outer and inner areas of the nodules. In contrast, the majority of the lymphatic vessel positivity was seen in the central zone in close apposition to the adult parasites, and the remainder usually associated with microfilariae in the outer areas of the nodule. These findings suggest an intimate relationship between adult O. volvulus and lymphatic vessels, including the likely proliferation of lymphatic endothelial cells (lymphangectasia) akin to that seen with other filariae. These findings indicate that adult O. volvulus may migrate via the lymphatic system, and that clinical manifestations of this disease that involve tissue edema may be the result of the location of these worms in the lymphatic system.

  9. Interaction of tumor cells and lymphatic vessels in cancer progression.

    PubMed

    Alitalo, A; Detmar, M

    2012-10-18

    Metastatic spread of cancer through the lymphatic system affects hundreds of thousands of patients yearly. Growth of new lymphatic vessels, lymphangiogenesis, is activated in cancer and inflammation, but is largely inactive in normal physiology, and therefore offers therapeutic potential. Key mediators of lymphangiogenesis have been identified in developmental studies. During embryonic development, lymphatic endothelial cells derive from the blood vascular endothelium and differentiate under the guidance of lymphatic-specific regulators, such as the prospero homeobox 1 transcription factor. Vascular endothelial growth factor-C (VEGF-C) and VEGF receptor 3 signaling are essential for the further development of lymphatic vessels and therefore they provide a promising target for inhibition of tumor lymphangiogenesis. Lymphangiogenesis is important for the progression of solid tumors as shown for melanoma and breast cancer. Tumor cells may use chemokine gradients as guidance cues and enter lymphatic vessels through intercellular openings between endothelial cell junctions or, possibly, by inducing larger discontinuities in the endothelial cell layer. Tumor-draining sentinel lymph nodes show enhanced lymphangiogenesis even before cancer metastasis and they may function as a permissive 'lymphovascular niche' for the survival of metastatic cells. Although our current knowledge indicates that the development of anti-lymphangiogenic therapies may be beneficial for the treatment of cancer patients, several open questions remain with regard to the frequency, mechanisms and biological importance of lymphatic metastases.

  10. How Do Meningeal Lymphatic Vessels Drain the CNS?

    PubMed

    Raper, Daniel; Louveau, Antoine; Kipnis, Jonathan

    2016-09-01

    The many interactions between the nervous and the immune systems, which are active in both physiological and pathological states, have recently become more clearly delineated with the discovery of a meningeal lymphatic system capable of carrying fluid, immune cells, and macromolecules from the central nervous system (CNS) to the draining deep cervical lymph nodes. However, the exact localization of the meningeal lymphatic vasculature and the path of drainage from the cerebrospinal fluid (CSF) to the lymphatics remain poorly understood. Here, we discuss the potential differences between peripheral and CNS lymphatic vessels and examine the purported mechanisms of CNS lymphatic drainage, along with how these may fit into established patterns of CSF flow. PMID:27460561

  11. Lymphatic Muscle Cells in Rat Mesenteric Lymphatic Vessels of Various Ages

    PubMed Central

    Bridenbaugh, Eric A.; Nizamutdinova, Irina Tsoy; Jupiter, Daniel; Nagai, Takashi; Thangaswamy, Sangeetha; Chatterjee, Victor

    2013-01-01

    Abstract Background Recent studies on aging-associated changes in mesenteric lymph flow in situ demonstrated predominance of the severe negative chronotropic effect of aging on the contractility of aged mesenteric lymphatic vessels (MLV). At the same time, contraction amplitude of the aged vessels was only slightly diminished by aging and can be rapidly stimulated within 5–15 minutes. However, the detailed quantitative evaluation of potential aging-associated changes in muscle cells investiture in MLV has never been performed. Methods and Results In this study we, for the first time, performed detailed evaluation of muscle cells investiture in MLV in reference to the position of lymphatic valve in different zones of lymphangion within various age groups (3-mo, 9-mo and 24-mo Fischer-344 rats). Using visual and quantitative analyses of the images of MLV immunohistochemically labeled for actin, we confirmed that the zones located close upstream (pre-valve zones) and above lymphatic valves (valve zones) possess the lowest investiture of lymphatic muscle cells. Most of the high muscle cells investiture zones exist downstream to the lymphatic valve (post-valve zones). The muscle cells investiture of these zones is not affected by aging, while pre-valve and valve zones demonstrate significant aging-associated decrease in muscle cells investiture. Conclusions The low muscle cells investiture zones in lymphatic vessels consist of predominantly longitudinally oriented muscle cells which are positioned in pre-valve and valve zones and connect adjacent lymphangions. These cells may provide important functional impact on the biomechanics of the lymphatic valve gating and electrical coupling between lymphangions, while their aging-associated changes may delimit adaptive reserves of aged lymphatic vessels. PMID:23531183

  12. Localization and proliferation of lymphatic vessels in the tympanic membrane in normal state and regeneration

    SciTech Connect

    Miyashita, Takenori; Burford, James L.; Hong, Young-Kwon; Gevorgyan, Haykanush; Lam, Lisa; Mori, Nozomu; Peti-Peterdi, Janos

    2013-10-25

    Highlights: •We newly developed the whole-mount imaging method of the tympanic membrane. •Lymphatic vessel loops were localized around the malleus handle and annulus tympanicus. •In regeneration, abundant lymphatic vessels were observed in the pars tensa. •Site-specific lymphatic vessels may play an important role in the tympanic membrane. -- Abstract: We clarified the localization of lymphatic vessels in the tympanic membrane and proliferation of lymphatic vessels during regeneration after perforation of the tympanic membrane by using whole-mount imaging of the tympanic membrane of Prox1 GFP mice. In the pars tensa, lymphatic vessel loops surrounded the malleus handle and annulus tympanicus. Apart from these locations, lymphatic vessel loops were not observed in the pars tensa in the normal tympanic membrane. Lymphatic vessel loops surrounding the malleus handle were connected to the lymphatic vessel loops in the pars flaccida and around the tensor tympani muscle. Many lymphatic vessel loops were detected in the pars flaccida. After perforation of the tympanic membrane, abundant lymphatic regeneration was observed in the pars tensa, and these regenerated lymphatic vessels extended from the lymphatic vessels surrounding the malleus at day 7. These results suggest that site-specific lymphatic vessels play an important role in the tympanic membrane.

  13. Cdk5 controls lymphatic vessel development and function by phosphorylation of Foxc2.

    PubMed

    Liebl, Johanna; Zhang, Siwei; Moser, Markus; Agalarov, Yan; Demir, Cansaran Saygili; Hager, Bianca; Bibb, James A; Adams, Ralf H; Kiefer, Friedemann; Miura, Naoyuki; Petrova, Tatiana V; Vollmar, Angelika M; Zahler, Stefan

    2015-01-01

    The lymphatic system maintains tissue fluid balance, and dysfunction of lymphatic vessels and valves causes human lymphedema syndromes. Yet, our knowledge of the molecular mechanisms underlying lymphatic vessel development is still limited. Here, we show that cyclin-dependent kinase 5 (Cdk5) is an essential regulator of lymphatic vessel development. Endothelial-specific Cdk5 knockdown causes congenital lymphatic dysfunction and lymphedema due to defective lymphatic vessel patterning and valve formation. We identify the transcription factor Foxc2 as a key substrate of Cdk5 in the lymphatic vasculature, mechanistically linking Cdk5 to lymphatic development and valve morphogenesis. Collectively, our findings show that Cdk5-Foxc2 interaction represents a critical regulator of lymphatic vessel development and the transcriptional network underlying lymphatic vascular remodeling. PMID:26027726

  14. Cdk5 controls lymphatic vessel development and function by phosphorylation of Foxc2.

    PubMed

    Liebl, Johanna; Zhang, Siwei; Moser, Markus; Agalarov, Yan; Demir, Cansaran Saygili; Hager, Bianca; Bibb, James A; Adams, Ralf H; Kiefer, Friedemann; Miura, Naoyuki; Petrova, Tatiana V; Vollmar, Angelika M; Zahler, Stefan

    2015-06-01

    The lymphatic system maintains tissue fluid balance, and dysfunction of lymphatic vessels and valves causes human lymphedema syndromes. Yet, our knowledge of the molecular mechanisms underlying lymphatic vessel development is still limited. Here, we show that cyclin-dependent kinase 5 (Cdk5) is an essential regulator of lymphatic vessel development. Endothelial-specific Cdk5 knockdown causes congenital lymphatic dysfunction and lymphedema due to defective lymphatic vessel patterning and valve formation. We identify the transcription factor Foxc2 as a key substrate of Cdk5 in the lymphatic vasculature, mechanistically linking Cdk5 to lymphatic development and valve morphogenesis. Collectively, our findings show that Cdk5-Foxc2 interaction represents a critical regulator of lymphatic vessel development and the transcriptional network underlying lymphatic vascular remodeling.

  15. Roles of transcriptional network during the formation of lymphatic vessels.

    PubMed

    Watabe, Tetsuro

    2012-09-01

    The lymphatic vascular system, also known as the second vascular system in vertebrates, plays crucial roles in various physiological and pathological processes. It participates in the maintenance of normal tissue fluid balance, trafficking of the immune cells and absorption of fatty acids in the gut. Furthermore, lymphatic system is associated with the pathogenesis of a number of diseases, including lymphedema, inflammatory diseases and tumour metastasis. Lymphatic vessels are comprised of lymphatic endothelial cells (LECs), which are differentiated from blood vascular endothelial cells. This review highlights recent advances in our understanding of the transcriptional control of LEC fate determination and reflects on efforts to understand the roles of transcriptional networks during this discrete developmental process.

  16. Short time effects of radiotherapy on lymphatic vessels and restorative lymphatic pathways: experimental approaches ina mouse model.

    PubMed

    Pastouret, F; Lievens, P; Leduc, O; Bourgeois, P; Tournel, K; Lamote, J; Zirak, C; Leduc, A

    2014-06-01

    Radiotherapy (RT) is an important component in the therapeutic approach to oncologic conditions. This study presents the investigative results on the impact of RT on lymphatic vessels and on the regenerative response of the lymphatic system in a mouse model. We first irradiated 3 groups of ten mice using brachytherapy in a single treatment of 20 Gy. We then performed morphological examination of the irradiated lymphatic vessels using an in vivo microscopic transillumination technique at 2, 4, and 6 weeks. Next we evaluated lymphatic flow using lymphoscintigraphy and in vivo microscopy at 6 to 11 weeks in: 10 additional mice following irradiation as above (IR), in 10 mice following incision of a lymphatic vessel (I), and in a non-treated control group of 10 mice (N). Intact lymphatic vessels were observed in all mice at 2, 4, and 8 weeks following the single dose of radiotherapy in the first group of mice and normal lymphatic flow was fully restored in the irradiated (IR) and incised (I) mice indicating that the reparative substitution lymphatic pathways are functioning normally. We found that following irradiation with one dose of 20 Gy, lymphatic vessels were not visibly damaged and also that lymphatic flow was consistently restored and substitutive lymphatic pathways formed.

  17. Structural and functional features of central nervous system lymphatic vessels.

    PubMed

    Louveau, Antoine; Smirnov, Igor; Keyes, Timothy J; Eccles, Jacob D; Rouhani, Sherin J; Peske, J David; Derecki, Noel C; Castle, David; Mandell, James W; Lee, Kevin S; Harris, Tajie H; Kipnis, Jonathan

    2015-07-16

    One of the characteristics of the central nervous system is the lack of a classical lymphatic drainage system. Although it is now accepted that the central nervous system undergoes constant immune surveillance that takes place within the meningeal compartment, the mechanisms governing the entrance and exit of immune cells from the central nervous system remain poorly understood. In searching for T-cell gateways into and out of the meninges, we discovered functional lymphatic vessels lining the dural sinuses. These structures express all of the molecular hallmarks of lymphatic endothelial cells, are able to carry both fluid and immune cells from the cerebrospinal fluid, and are connected to the deep cervical lymph nodes. The unique location of these vessels may have impeded their discovery to date, thereby contributing to the long-held concept of the absence of lymphatic vasculature in the central nervous system. The discovery of the central nervous system lymphatic system may call for a reassessment of basic assumptions in neuroimmunology and sheds new light on the aetiology of neuroinflammatory and neurodegenerative diseases associated with immune system dysfunction.

  18. Visualisation and stereological assessment of blood and lymphatic vessels.

    PubMed

    Lokmic, Zerina; Mitchell, Geraldine M

    2011-06-01

    The physiological processes involved in tissue development and regeneration also include the parallel formation of blood and lymphatic vessel circulations which involves their growth, maturation and remodelling. Both vascular systems are also frequently involved in the development and progression of pathological conditions in tissues and organs. The blood vascular system circulates oxygenated blood and nutrients at appropriate physiological levels for tissue survival, and efficiently removes all waste products including carbon dioxide. This continuous network consists of the heart, aorta, arteries, arterioles, capillaries, post-capillary venules, venules, veins and vena cava. This system exists in an interstitial environment together with the lymphatic vascular system, including lymph nodes, which aids maintenance of body fluid balance and immune surveillance. To understand the process of vascular development, vascular network stability, remodelling and/or regression in any research model under any experimental conditions, it is necessary to clearly and unequivocally identify and quantify all elements of the vascular network. By utilising stereological methods in combination with cellular markers for different vascular cell components, it is possible to estimate parameters such as surface density and surface area of blood vessels, length density and length of blood vessels as well as absolute vascular volume. This review examines the current strategies used to visualise blood vessels and lymphatic vessels in two- and three-dimensions and the basic principles of vascular stereology used to quantify vascular network parameters.

  19. Aberrant mural cell recruitment to lymphatic vessels and impaired lymphatic drainage in a murine model of pulmonary fibrosis.

    PubMed

    Meinecke, Anna-Katharina; Nagy, Nadine; Lago, Gabriela D'Amico; Kirmse, Santina; Klose, Ralph; Schrödter, Katrin; Zimmermann, Annika; Helfrich, Iris; Rundqvist, Helene; Theegarten, Dirk; Anhenn, Olaf; Orian-Rousseau, Véronique; Johnson, Randall S; Alitalo, Kari; Fischer, Jens W; Fandrey, Joachim; Stockmann, Christian

    2012-06-14

    Pulmonary fibrosis is a progressive disease with unknown etiology that is characterized by extensive remodeling of the lung parenchyma, ultimately resulting in respiratory failure. Lymphatic vessels have been implicated with the development of pulmonary fibrosis, but the role of the lymphatic vasculature in the pathogenesis of pulmonary fibrosis remains enigmatic. Here we show in a murine model of pulmonary fibrosis that lymphatic vessels exhibit ectopic mural coverage and that this occurs early during the disease. The abnormal lymphatic vascular patterning in fibrotic lungs was driven by expression of platelet-derived growth factor B (PDGF-B) in lymphatic endothelial cells and signaling through platelet-derived growth factor receptor (PDGFR)-β in associated mural cells. Because of impaired lymphatic drainage, aberrant mural cell coverage fostered the accumulation of fibrogenic molecules and the attraction of fibroblasts to the perilymphatic space. Pharmacologic inhibition of the PDGF-B/PDGFR-β signaling axis disrupted the association of mural cells and lymphatic vessels, improved lymphatic drainage of the lung, and prevented the attraction of fibroblasts to the perilymphatic space. Our results implicate aberrant mural cell recruitment to lymphatic vessels in the pathogenesis of pulmonary fibrosis and that the drainage capacity of pulmonary lymphatics is a critical mediator of fibroproliferative changes.

  20. Mechanisms of VIP-induced inhibition of the lymphatic vessel pump.

    PubMed

    von der Weid, Pierre-Yves; Rehal, Sonia; Dyrda, Peter; Lee, Stewart; Mathias, Ryan; Rahman, Mozibur; Roizes, Simon; Imtiaz, Mohammad S

    2012-06-01

    Lymphatic vessels serve as a route by which interstitial fluid, protein and other macromolecules are returned to the blood circulation and immune cells and antigens gain access to lymph nodes. Lymph flow is an active process promoted by rhythmical contraction-relaxation events occurring in the collecting lymphatic vessels. This lymphatic pumping is an intrinsic property of the lymphatic muscles in the vessel wall and consequent to action potentials. Compromised lymphatic pumping may affect lymph and immune cell transport, an action which could be particularly detrimental during inflammation. Importantly, many inflammatory mediators alter lymphatic pumping. Vasoactive intestinal peptide (VIP) is a neuro- and immuno-modulator thought to be released by nerve terminals and immune cells in close proximity to lymphatic vessels. We demonstrated the presence of the peptide in lymphatic vessels and in the lymph and examined the effects of VIP on mesenteric collecting lymphatic vessels of the guinea pig using pharmacological bioassays, intracellular microelectrode electrophysiology, immunofluorescence and quantitative real-time PCR. We showed that VIP alters lymphatic pumping by decreasing the frequency of lymphatic contractions and hyperpolarizing the lymphatic muscle membrane potential in a concentration-dependent manner. Our data further suggest that these effects are mainly mediated by stimulation of the VIP receptor VPAC2 located on the lymphatic muscle and the downstream involvement of protein kinase A (PKA) and ATP-sensitive K⁺ (KATP) channels. Inhibition of lymphatic pumping by VIP may compromise lymph drainage, oedema resolution and immune cell trafficking to the draining lymph nodes.

  1. Lymphatic vessels in the development of tissue and organ rejection.

    PubMed

    Hos, Deniz; Cursiefen, Claus

    2014-01-01

    The lymphatic vascular system-amongst other tasks-is critically involved in the regulation of adaptive immune responses as it provides an important route for APC trafficking to secondary lymphatic organs. In this context, the cornea, which is the transparent and physiologically avascular "windscreen" of the eye, has served as an excellent in vivo model to study the role of the blood and lymphatic vasculature in mediating allogenic immune responses after transplantation. Especially the mouse model of high-risk corneal transplantation, where corneal avascularity is abolished by a severe inflammatory stimulus prior to keratoplasty, allows for comparison to other transplantations performed in primarily vascularized tissues and solid organs. Using this model, we recently demonstrated that especially lymphatic vessels, but not blood vessels, define the high-risk status of vascularized corneas and that anti(lymph)angiogenic treatment significantly promotes corneal allograft survival. Since evidence for lymphangiogenesis and its potential association with graft rejection is nowadays also present in solid organ transplantation, studies are currently addressing the potential benefits of anti(lymph)angiogenic treatment as a novel therapeutic concept also in solid organ grafting with promising initial results.

  2. Smooth muscle–endothelial cell communication activates Reelin signaling and regulates lymphatic vessel formation

    PubMed Central

    Lutter, Sophie; Xie, Sherry; Tatin, Florence

    2012-01-01

    Active lymph transport relies on smooth muscle cell (SMC) contractions around collecting lymphatic vessels, yet regulation of lymphatic vessel wall assembly and lymphatic pumping are poorly understood. Here, we identify Reelin, an extracellular matrix glycoprotein previously implicated in central nervous system development, as an important regulator of lymphatic vascular development. Reelin-deficient mice showed abnormal collecting lymphatic vessels, characterized by a reduced number of SMCs, abnormal expression of lymphatic capillary marker lymphatic vessel endothelial hyaluronan receptor 1 (LYVE-1), and impaired function. Furthermore, we show that SMC recruitment to lymphatic vessels stimulated release and proteolytic processing of endothelium-derived Reelin. Lymphatic endothelial cells in turn responded to Reelin by up-regulating monocyte chemotactic protein 1 (MCP1) expression, which suggests an autocrine mechanism for Reelin-mediated control of endothelial factor expression upstream of SMC recruitment. These results uncover a mechanism by which Reelin signaling is activated by communication between the two cell types of the collecting lymphatic vessels—smooth muscle and endothelial cells—and highlight a hitherto unrecognized and important function for SMCs in lymphatic vessel morphogenesis and function. PMID:22665518

  3. Tie1 is required for lymphatic valve and collecting vessel development

    PubMed Central

    Qu, Xianghu; Zhou, Bin; Baldwin, H. Scott

    2015-01-01

    Tie1 is a receptor tyrosine kinase with broad expression in embryonic endothelium. Reduction of Tie1 levels in mouse embryos with a hypomorphic Tie1 allele resulted in abnormal lymphatic patterning and architecture, decreased lymphatic draining efficiency, and ultimately, embryonic demise. Here we report that Tie1 is present uniformly throughout the lymphatics and from late embryonic/early postnatal stages, becomes more restricted to lymphatic valve regions. To investigate later events of lymphatic development, we employed Cre-loxP recombination utilizing a floxed Tie1 allele and an Nfatc1Cre line, to provide loxP excision predominantly in lymphatic endothelium and developing valves. Interestingly, unlike the early prenatal defects previously described by ubiquitous endothelial deletion, excision of Tie1 with Nfatc1Cre resulted in abnormal lymphatic defects in postnatal mice and was characterized by agenesis of lymphatic valves and a deficiency of collecting lymphatic vessels. Attenuation of Tie1 signaling in lymphatic endothelium prevented initiation of lymphatic valve specification by Prox1 high expression lymphatic endothelial cells that is associated with the onset of turbulent flow in the lymphatic circulation. Our findings reveal a fundamental role for Tie signaling during lymphatic vessel remodeling and valve morphogenesis and implicate it as a candidate gene involved in primary lymphedema. PMID:25576926

  4. Tie1 is required for lymphatic valve and collecting vessel development.

    PubMed

    Qu, Xianghu; Zhou, Bin; Scott Baldwin, H

    2015-03-01

    Tie1 is a receptor tyrosine kinase with broad expression in embryonic endothelium. Reduction of Tie1 levels in mouse embryos with a hypomorphic Tie1 allele resulted in abnormal lymphatic patterning and architecture, decreased lymphatic draining efficiency, and ultimately, embryonic demise. Here we report that Tie1 is present uniformly throughout the lymphatics and from late embryonic/early postnatal stages, becomes more restricted to lymphatic valve regions. To investigate later events of lymphatic development, we employed Cre-loxP recombination utilizing a floxed Tie1 allele and an Nfatc1Cre line, to provide loxP excision predominantly in lymphatic endothelium and developing valves. Interestingly, unlike the early prenatal defects previously described by ubiquitous endothelial deletion, excision of Tie1 with Nfatc1Cre resulted in abnormal lymphatic defects in postnatal mice and was characterized by agenesis of lymphatic valves and a deficiency of collecting lymphatic vessels. Attenuation of Tie1 signaling in lymphatic endothelium prevented initiation of lymphatic valve specification by Prox1 high expression lymphatic endothelial cells that is associated with the onset of turbulent flow in the lymphatic circulation. Our findings reveal a fundamental role for Tie1 signaling during lymphatic vessel remodeling and valve morphogenesis and implicate it as a candidate gene involved in primary lymphedema.

  5. Decline of lymphatic vessel density and function in murine skin during aging.

    PubMed

    Karaman, Sinem; Buschle, Dorina; Luciani, Paola; Leroux, Jean-Christophe; Detmar, Michael; Proulx, Steven T

    2015-10-01

    Lymphatic vessels play important roles in the pathogenesis of many conditions that have an increased prevalence in the elderly population. However, the effects of the aging process on the lymphatic system are still relatively unknown. We have applied non-invasive imaging and whole-mount staining techniques to assess the lymphatic vessel function and morphology in three different age groups of mice: 2 months (young), 7 months (middle-aged), and 18 months (aged). We first developed and validated a new method to quantify lymphatic clearance from mouse ear skin, using a lymphatic-specific near-infrared tracer. Using this method, we found that there is a prominent decrease in lymphatic vessel function during aging since the lymphatic clearance was significantly delayed in aged mice. This loss of function correlated with a decreased lymphatic vessel density and a reduced lymphatic network complexity in the skin of aged mice as compared to younger controls. The blood vascular leakage in the skin was slightly increased in the aged mice, indicating that the decreased lymphatic function was not caused by a reduced capillary filtration in aged skin. The decreased function of lymphatic vessels with aging might have implications for the pathogenesis of a number of aging-related diseases.

  6. Higher blood vessel density in comparison to the lymphatic vessels in oral squamous cell carcinoma

    PubMed Central

    Maturana-Ramírez, Andrea; Espinoza, Iris; Reyes, Montserrat; Aitken, Juan Pablo; Aguayo, Francisco; Hartel, Steffen; Rojas-Alcayaga, Gonzalo

    2015-01-01

    Introduction: Oral squamous cell carcinoma (OSCC) is characterized by local invasion and the development of cervical metastasis. In the tongue, an association between the invasion of the lymphatic vessels and the development of metastasis in the regional lymph nodes has been demonstrated. Moreover, invasion of the blood vessels is associated with greater recurrence and poorer prognoses. Therefore, the presence and density of lymphatic and blood vessels in intra- and peritumoral tissues should play an important role in the progression, dissemination and metastasis of carcinomas. However, the evidence regarding OSCC is inconclusive. The aim of this study was to determine the comparison and association between the lymphatic (D2-40) and blood vessel (CD34) densities in intratumoral OSCC tissue. Materials and Methods: Thirty-seven cases diagnosed as OSCC between the years 2000 and 2008 were obtained from the Anatomic Pathology Service of the School of Dentistry, University of Chile. The immunohistochemical markers D2-40 and CD34 were used, and the densities (mm2) of lymphatic vessels (LVD) and blood vessels (BVD) in the intratumoral region were determined. The relationship between LVD and BVD values was evaluated. Results: There were significant association between the CD34 and D2-40 expression (rho=0.4, P<0.05) and between the LVD and the location in the tongue (P=0.019). The BVD was greater (128.0 vessels/mm2) than the LVD (42.9 vessels/mm2), and there was a positive correlation between the LVD and BVD. Conclusions: In OSCC, the BVD is greater than the LVD, and there is a moderate correlation between the two quantities. PMID:26722595

  7. Thymus cell antigen 1 (Thy1, CD90) is expressed by lymphatic vessels and mediates cell adhesion to lymphatic endothelium.

    PubMed

    Jurisic, Giorgia; Iolyeva, Maria; Proulx, Steven T; Halin, Cornelia; Detmar, Michael

    2010-10-15

    The lymphatic vascular system plays an important role in inflammation and cancer progression, although the molecular mechanisms involved are poorly understood. As determined by comparative transcriptional profiling studies of ex vivo isolated mouse intestinal lymphatic endothelial cells versus blood vascular endothelial cells, thymus cell antigen 1 (Thy1, CD90) was expressed at much higher levels in lymphatic endothelial cells than in blood vascular endothelial cells. These findings were confirmed by quantitative PCR, and at the protein level by FACS and immunofluorescence analyses. Thy1 was also strongly expressed by tumor-associated lymphatic vessels, as evaluated in a B16 melanoma footpad model in mice. Blockade of Thy1 inhibited tumor cell adhesion to cultured mouse lymphatic endothelial cells. Importantly, treatment of human dermal microvascular endothelial cells with tumor necrosis factor or phorbol 12-myristate 13-acetate resulted in Thy1 upregulation in podoplanin-expressing lymphatic endothelial cells, but not in podoplanin-negative blood vascular endothelial cells. Moreover, adhesion of human polymorphonuclear and mononuclear leukocytes to human lymphatic endothelial cells was Thy1-dependent. Together, these results identify Thy1 as a novel lymphatic vessel expressed gene and suggest its potential role in the cell adhesion processes required for tumor progression and inflammation.

  8. Lysophosphatidic acid does not cause blood/lymphatic vessel plasticity in the rat mesentery culture model.

    PubMed

    Sweat, Richard S; Azimi, Mohammad S; Suarez-Martinez, Ariana D; Katakam, Prasad; Murfee, Walter L

    2016-07-01

    Understanding the mechanisms behind endothelial cell identity is crucial for the goal of manipulating microvascular networks. Lysophosphatidic acid (LPA) and serum stimulation have been suggested to induce a lymphatic identity in blood endothelial cells in vitro. The objective of this study was to determine if LPA or serum induces blood-to-lymphatic vessel phenotypic transition in microvascular networks. The rat mesentery culture model was used to observe the effect of stimulation on blood and lymphatic microvascular networks ex vivo. Vascularized mesenteric tissues were harvested from adult Wistar rats and cultured with LPA or 10% serum for up to 5 days. Tissues were then immunolabeled with PECAM to identify blood vessels and LYVE-1 or Prox1 to identify lymphatic vessels. We show that while LPA caused capillary sprouting and increased vascular length density in adult microvascular networks, LPA did not cause a blood-to-lymphatic phenotypic transition. The results suggest that LPA is not sufficient to cause blood endothelial cells to adopt a lymphatic identity in adult microvascular networks. Similarly, serum stimulation caused robust angiogenesis and increased lymphatic/blood vessel connections, yet did not induce a blood-to-lymphatic phenotypic transition. Our study highlights an understudied area of lymphatic research and warrants future investigation into the mechanisms responsible for the maintenance of blood and lymphatic vessel identity. PMID:27401461

  9. Lysophosphatidic acid does not cause blood/lymphatic vessel plasticity in the rat mesentery culture model.

    PubMed

    Sweat, Richard S; Azimi, Mohammad S; Suarez-Martinez, Ariana D; Katakam, Prasad; Murfee, Walter L

    2016-07-01

    Understanding the mechanisms behind endothelial cell identity is crucial for the goal of manipulating microvascular networks. Lysophosphatidic acid (LPA) and serum stimulation have been suggested to induce a lymphatic identity in blood endothelial cells in vitro. The objective of this study was to determine if LPA or serum induces blood-to-lymphatic vessel phenotypic transition in microvascular networks. The rat mesentery culture model was used to observe the effect of stimulation on blood and lymphatic microvascular networks ex vivo. Vascularized mesenteric tissues were harvested from adult Wistar rats and cultured with LPA or 10% serum for up to 5 days. Tissues were then immunolabeled with PECAM to identify blood vessels and LYVE-1 or Prox1 to identify lymphatic vessels. We show that while LPA caused capillary sprouting and increased vascular length density in adult microvascular networks, LPA did not cause a blood-to-lymphatic phenotypic transition. The results suggest that LPA is not sufficient to cause blood endothelial cells to adopt a lymphatic identity in adult microvascular networks. Similarly, serum stimulation caused robust angiogenesis and increased lymphatic/blood vessel connections, yet did not induce a blood-to-lymphatic phenotypic transition. Our study highlights an understudied area of lymphatic research and warrants future investigation into the mechanisms responsible for the maintenance of blood and lymphatic vessel identity.

  10. Lipopolysaccharide modulates neutrophil recruitment and macrophage polarization on lymphatic vessels and impairs lymphatic function in rat mesentery.

    PubMed

    Chakraborty, Sanjukta; Zawieja, Scott D; Wang, Wei; Lee, Yang; Wang, Yuan J; von der Weid, Pierre-Yves; Zawieja, David C; Muthuchamy, Mariappan

    2015-12-15

    Impairment of the lymphatic system is apparent in multiple inflammatory pathologies connected to elevated endotoxins such as LPS. However, the direct mechanisms by which LPS influences the lymphatic contractility are not well understood. We hypothesized that a dynamic modulation of innate immune cell populations in mesentery under inflammatory conditions perturbs tissue cytokine/chemokine homeostasis and subsequently influences lymphatic function. We used rats that were intraperitoneally injected with LPS (10 mg/kg) to determine the changes in the profiles of innate immune cells in the mesentery and in the stretch-mediated contractile responses of isolated lymphatic preparations. Results demonstrated a reduction in the phasic contractile activity of mesenteric lymphatic vessels from LPS-injected rats and a severe impairment of lymphatic pump function and flow. There was a significant reduction in the number of neutrophils and an increase in monocytes/macrophages present on the lymphatic vessels and in the clear mesentery of the LPS group. This population of monocytes and macrophages established a robust M2 phenotype, with the majority showing high expression of CD163 and CD206. Several cytokines and chemoattractants for neutrophils and macrophages were significantly changed in the mesentery of LPS-injected rats. Treatment of lymphatic muscle cells (LMCs) with LPS showed significant changes in the expression of adhesion molecules, VCAM1, ICAM1, CXCR2, and galectin-9. LPS-TLR4-mediated regulation of pAKT, pERK pI-κB, and pMLC20 in LMCs promoted both contractile and inflammatory pathways. Thus, our data provide the first evidence connecting the dynamic changes in innate immune cells on or near the lymphatics and complex cytokine milieu during inflammation with lymphatic dysfunction.

  11. By Different Cellular Mechanisms, Lymphatic Vessels Sprout by Endothelial Cell Recruitment Whereas Blood Vessels Grow by Vascular Expansion

    NASA Technical Reports Server (NTRS)

    Parsons-Wingerter, Patricia; McKay, Terri L.; Leontiev, Dmitry; Condrich, Terence K.; DiCorleto, Paul E.

    2005-01-01

    The development of effective vascular therapies requires the understanding of all modes of vessel formation contributing to vasculogenesis, angiogenesis (here termed hemangiogenesis) and lymphangiogenesis. We show that lymphangiogenesis proceeds by blind-ended vessel sprouting via recruitment of isolated endothelial progenitor cells to the tips of growing vessels, whereas hemangiogenesis occurs by non-sprouting vessel expansion from the capillary network, during middevelopment in the quail chorioallantoic membrane (CAM). Blood vessels expanded out of capillaries that displayed transient expression of alpha smooth muscle actin (alphaSMA), accompanied by mural recruitment of migratory progenitor cells expressing SMA. Lymphatics and blood vessels were identified by confocal/fluorescence microscopy of vascular endothelial growth factor (VEGF) receptors VEGFR-1 and VEGFR-2, alphaSMA (expressed on CAM blood vessels but not on lymphatics), homeobox transcription factor Prox-1 (specific to CAM lymphatic endothelium), and the quail hematopoetic/vascular marker, QH-1. Expression of VEGFR-1 was highly restricted to blood vessels (primarily capillaries). VEGFR-2 was expressed intensely in isolated hematopoietic cells, lymphatic vessels and moderately in blood vessels. Prox-1 was absent from endothelial progenitor cells prior to lymphatic recruitment. Although vascular endothelial growth factor-165 (VEGF(sub 165)) is a key regulator of numerous cellular processes in hemangiogenesis and vasculogenesis, the role of VEGF(sub 165) in lymphangiogenesis is less clear. Exogenous VEGF(sub 165) increased blood vessel density without changing endogenous modes of vascular/lymphatic vessel formation or marker expression patterns. However, VEGF(sub 165) did increase the frequency of blood vascular anastomoses and strongly induced the antimaturational dissociation of lymphatics from blood vessels, with frequent formation of homogeneous lymphatic networks.

  12. Basement membrane protein distribution in LYVE-1-immunoreactive lymphatic vessels of normal tissues and ovarian carcinomas.

    PubMed

    Vainionpää, Noora; Bützow, Ralf; Hukkanen, Mika; Jackson, David G; Pihlajaniemi, Taina; Sakai, Lynn Y; Virtanen, Ismo

    2007-05-01

    The endothelial cells of blood vessels assemble basement membranes that play a role in vessel formation, maintenance and function, and in the migration of inflammatory cells. However, little is known about the distribution of basement membrane constituents in lymphatic vessels. We studied the distribution of basement membrane proteins in lymphatic vessels of normal human skin, digestive tract, ovary and, as an example of tumours with abundant lymphatics, ovarian carcinomas. Basement membrane proteins were localized by immunohistochemistry with monoclonal antibodies, whereas lymphatic capillaries were detected with antibodies to the lymphatic vessel endothelial hyaluronan receptor-1, LYVE-1. In skin and ovary, fibrillar immunoreactivity for the laminin alpha4, beta1, beta2 and gamma1 chains, type IV and XVIII collagens and nidogen-1 was found in the basement membrane region of the lymphatic endothelium, whereas also heterogeneous reactivity for the laminin alpha5 chain was detected in the digestive tract. Among ovarian carcinomas, intratumoural lymphatic vessels were found especially in endometrioid carcinomas. In addition to the laminin alpha4, beta1, beta2 and gamma1 chains, type IV and XVIII collagens and nidogen-1, carcinoma lymphatics showed immunoreactivity for the laminin alpha5 chain and Lutheran glycoprotein, a receptor for the laminin alpha5 chain. In normal lymphatic capillaries, the presence of primarily alpha4 chain laminins may therefore compromise the formation of endothelial basement membrane, as these truncated laminins lack one of the three arms required for efficient network assembly. The localization of basement membrane proteins adjacent to lymphatic endothelia suggests a role for these proteins in lymphatic vessels. The distribution of the laminin alpha5 chain and Lutheran glycoprotein proposes a difference between normal and carcinoma lymphatic capillaries.

  13. Immunohistochemical study of the lymphatic vessels in major salivary glands of the rat.

    PubMed

    Aiyama, Shigeo; Kikuchi, Kenichiro; Takada, Kiyomi; Ikeda, Rie; Sato, Sumie; Kuroki, Jyunya

    2011-02-01

    This study was designed to examine whether lymphatic vessels are present in the lobules of major salivary glands in the rat. Immunostaining with an antibody against podoplanin, a lymphatic endothelial cell marker, was performed on sections of the submandibular, sublingual and parotid glands. Light microscopy demonstrated podoplanin-positive lymphatic vessels around the interlobular ducts and the interlobular arteries and veins in the interlobular connective tissue in all of the major salivary glands. No podoplanin-positive lymphatic vessels were found in the lobules. Electron microscopy also demonstrated lymphatic endothelial cells showing podoplanin expression only in the interlobular connective tissue. These findings suggest that the lymphatic system of the rat major salivary glands originates in the interlobular connective tissue, and not in the lobules.

  14. Quantitative study of the topographic distribution of conjunctival lymphatic vessels in the monkey.

    PubMed

    Guo, Wenyi; Zhu, Yuanfang; Yu, Paula K; Yu, Xiaobo; Sun, Xinghuai; Cringle, Stephen J; Su, Er-Ning; Yu, Dao-Yi

    2012-01-01

    The purpose of this study was to quantify the topographic distribution of bulbar conjunctival microlymphatic vessels in the monkey. Sixteen eyes from 8 rhesus monkeys were used. Full thickness pieces of globe wall were excised from each quadrant. Cryosections were stained for 5'-nucleotidase, an enzyme histochemical staining for lymphatic vessels, or vascular endothelial growth factor receptor-3, an immunohistochemical marker for the identification of lymphatic endothelial cells, and then counterstained by hematoxylin. The remaining bulbar conjunctiva was dissected and flat mounted. The tissue was then processed with 5'-nucleotidase and alkaline phosphatase, an enzyme histochemical stain with higher activity in blood vessels. Microscope images were further analysed by image processing. The density of lymphatics, diameter of lymphatic vessels, and the size of the drainage zone of each blind end of the initial lymphatics were studied. Conjunctival lymphatics consisted of initial lymphatics and pre-collectors. The initial lymphatics with blind ends were predominately distributed just under the epithelium. The density of these lymphatics (∼50%) and the drainage zone area (∼0.81 mm(2)) was similar in each quadrant, with no difference in the limbus and fornix regions. The average diameter of lymphatic vessels in each quadrant ranged from 82 to 111 μm, and was greater in the superior and nasal regions. Larger calibre pre-collectors with valve-like structures were mostly located sub Tenon's membrane and predominantly located in the region mid-way between the limbus and fornix. There was a marked depth difference in initial lymphatic distribution, with the initial lymphatics mostly confined to the region between Tenon's membrane and the conjunctival epithelium. Detailed knowledge of the topographic distribution of conjunctival lymphatics have significant relevance to a better understanding of immunology, drug delivery, glaucoma filtration surgery, and tumour

  15. Differential permeability of lymphatic and blood vessels in determining the route of metastasis as demonstrated by indirect lymphography.

    PubMed

    Kim, U; Park, H C; Choi, K H

    1988-01-01

    Indirect mammo-lymphography with serial radiograms was made on rats bearing three established rat mammary carcinomas (SMT-2A, TMT-50, MT-W9B), with the water-soluble contrast medium, Iotasul. In the lymphogenously metastasizing SMT-2A, fine lymphatic sprouts from the tumor were seen converging into an afferent lymph vessel that was extending toward a metastatic regional lymph node, in 15-30 min. For 45 min, the dye remained localized in the primary tumor with no other vascular structures or viscera visible until it emerged in the urinary bladder, indicating that Iotasul was absorbed slowly into the systemic circulation via lymphatics and diluted beyond recognition by lymph and blood, and then reconcentrated in urine. In contrast, in the hematogenously metastasizing TMT-50, Iotasul was rapidly diffused into the blood stream, revealing the inferior caval vein within 5 min, and by 15 min the heart, aorta, common carotid arteries, kidney and ureter were all clearly revealed. In the non-metastasizing MT-W9B host, several small vascular markings around the tumor were seen by 10 min and the outline of kidneys and urinary bladder in 15 min, suggesting that the dye was also absorbed through blood capillaries but somewhat slowly. Thus, the differential vascular permeability in rat mammary tumors revealed by Iotasul has not only helped to distinguish lymphatics from blood vessels, but also to correlate it with their metastatic potential.

  16. Network development in biological gels: role in lymphatic vessel development.

    PubMed

    Roose, Tiina; Fowler, Andrew C

    2008-08-01

    In this paper, we present a model that explains the prepatterning of lymphatic vessel morphology in collagen gels. This model is derived using the theory of two phase rubber material due to Flory and coworkers and it consists of two coupled fourth order partial differential equations describing the evolution of the collagen volume fraction, and the evolution of the proton concentration in a collagen implant; as described in experiments of Boardman and Swartz (Circ. Res. 92, 801-808, 2003). Using linear stability analysis, we find that above a critical level of proton concentration, spatial patterns form due to small perturbations in the initially uniform steady state. Using a long wavelength reduction, we can reduce the two coupled partial differential equations to one fourth order equation that is very similar to the Cahn-Hilliard equation; however, it has more complex nonlinearities and degeneracies. We present the results of numerical simulations and discuss the biological implications of our model. PMID:18622650

  17. In vivo visualization and quantification of collecting lymphatic vessel contractility using near-infrared imaging

    PubMed Central

    Chong, Chloé; Scholkmann, Felix; Bachmann, Samia B.; Luciani, Paola; Leroux, Jean-Christophe; Detmar, Michael; Proulx, Steven T.

    2016-01-01

    Techniques to image lymphatic vessel function in either animal models or in the clinic are limited. In particular, imaging methods that can provide robust outcome measures for collecting lymphatic vessel function are sorely needed. In this study, we aimed to develop a method to visualize and quantify collecting lymphatic vessel function in mice, and to establish an in vivo system for evaluation of contractile agonists and antagonists using near-infrared fluorescence imaging. The flank collecting lymphatic vessel in mice was exposed using a surgical technique and a near-infrared tracer was infused into the inguinal lymph node. Collecting lymphatic vessel contractility and valve function could be easily visualized after the infusion. A diameter tracking method was established and the diameter of the vessel was found to closely correlate to near-infrared fluorescence signal. Phasic contractility measures of frequency and amplitude were established using an automated algorithm. The methods were validated by tracking the vessel response to topical application of a contractile agonist, prostaglandin F2α, and by demonstrating the potential of the technique for non-invasive evaluation of modifiers of lymphatic function. These new methods will enable high-resolution imaging and quantification of collecting lymphatic vessel function in animal models and may have future clinical applications. PMID:26960708

  18. Nodal lymph flow quantified with afferent vessel input function allows differentiation between normal and cancer-bearing nodes

    PubMed Central

    DSouza, Alisha V.; Elliott, Jonathan T.; Gunn, Jason R.; Barth, Richard J.; Samkoe, Kimberley S.; Tichauer, Kenneth M.; Pogue, Brian W.

    2015-01-01

    Morbidity and complexity involved in lymph node staging via surgical resection and biopsy could ideally be improved using node assay techniques that are non-invasive. While visible blue dyes are often used to locate the sentinel lymph nodes from draining lymphatic vessels near a tumor, they do not provide an in situ metric to evaluate presence of cancer. In this study, the transport kinetics of methylene blue were analyzed to determine the potential for better in situ information about metastatic involvement in the nodes. A rat model with cancer cells in the axillary lymph nodes was used, with methylene blue injection to image the fluorescence kinetics. The lymphatic flow from injection sites to nodes was imaged and the relative kinetics from feeding lymphatic ducts relative to lymph nodes was quantified. Large variability existed in raw fluorescence and transport patterns within each cohort resulting in no systematic difference between average nodal uptake in normal, sham control and cancer-bearing nodes. However, when the signal from the afferent lymph vessel fluorescence was used to normalize the signal of the lymph nodes, the high signal heterogeneity was reduced. Using a model, the lymph flow through the nodes (FLN) was estimated to be 1.49 ± 0.64 ml/g/min in normal nodes, 1.53 ± 0.45 ml/g/min in sham control nodes, and reduced to 0.50 ± 0.24 ml/g/min in cancer-cell injected nodes. This summarizes the significant difference (p = 0.0002) between cancer-free and cancer-bearing nodes in normalized flow. This process of normalized flow imaging could be used as an in situ tool to detect metastatic involvement in nodes. PMID:25909014

  19. Development and validation of a custom made indocyanine green fluorescence lymphatic vessel imager.

    PubMed

    Pallotta, Olivia J; van Zanten, Malou; McEwen, Mark; Burrow, Lynne; Beesley, Jack; Piller, Neil

    2015-06-01

    Lymphoedema is a chronic progressive condition often producing significant morbidity. An in-depth understanding of an individual's lymphatic architecture is valuable both in the understanding of underlying pathology and for targeting and tailoring treatment. Severe lower limb injuries resulting in extensive loss of soft tissue require transposition of a flap consisting of muscle and/or soft tissue to close the defect. These patients are at risk of lymphoedema and little is known about lymphatic regeneration within the flap. Indocyanine green (ICG), a water-soluble dye, has proven useful for the imaging of lymphatic vessels. When injected into superficial tissues it binds to plasma proteins in lymph. By exposing the dye to specific wavelengths of light, ICG fluoresces with near-infrared light. Skin is relatively transparent to ICG fluorescence, enabling the visualization and characterization of superficial lymphatic vessels. An ICG fluorescence lymphatic vessel imager was manufactured to excite ICG and visualize real-time fluorescence as it travels through the lymphatic vessels. Animal studies showed successful ICG excitation and detection using this imager. Clinically, the imager has assisted researchers to visualize otherwise hidden superficial lymphatic pathways in patients postflap surgery. Preliminary results suggest superficial lymphatic vessels do not redevelop in muscle flaps.

  20. Development and validation of a custom made indocyanine green fluorescence lymphatic vessel imager

    NASA Astrophysics Data System (ADS)

    Pallotta, Olivia J.; van Zanten, Malou; McEwen, Mark; Burrow, Lynne; Beesley, Jack; Piller, Neil

    2015-06-01

    Lymphoedema is a chronic progressive condition often producing significant morbidity. An in-depth understanding of an individual's lymphatic architecture is valuable both in the understanding of underlying pathology and for targeting and tailoring treatment. Severe lower limb injuries resulting in extensive loss of soft tissue require transposition of a flap consisting of muscle and/or soft tissue to close the defect. These patients are at risk of lymphoedema and little is known about lymphatic regeneration within the flap. Indocyanine green (ICG), a water-soluble dye, has proven useful for the imaging of lymphatic vessels. When injected into superficial tissues it binds to plasma proteins in lymph. By exposing the dye to specific wavelengths of light, ICG fluoresces with near-infrared light. Skin is relatively transparent to ICG fluorescence, enabling the visualization and characterization of superficial lymphatic vessels. An ICG fluorescence lymphatic vessel imager was manufactured to excite ICG and visualize real-time fluorescence as it travels through the lymphatic vessels. Animal studies showed successful ICG excitation and detection using this imager. Clinically, the imager has assisted researchers to visualize otherwise hidden superficial lymphatic pathways in patients postflap surgery. Preliminary results suggest superficial lymphatic vessels do not redevelop in muscle flaps.

  1. The embryonic origins of lymphatic vessels: an historical review.

    PubMed

    Ribatti, Domenico; Crivellato, Enrico

    2010-06-01

    Work on the lymphatic system began in the 17th century, and by the beginning of the 19th century the anatomy of most of the lymphatic system had been described. One of the most important questions in this field has been the determination of the embryological origin of the lymphatic endothelium. Two theories were proposed. The first suggested that lymphatic endothelium derived by sprouting from venous endothelium, the so-called centrifugal theory. The second, the so-called centripetal theory, suggested that lymphatic endothelium differentiates in situ from primitive mesenchyme, and secondarily acquires connection with the vascular system. More recent evidence has provided support for both hypotheses.

  2. Regulation of lymphatic-blood vessel separation by endothelial Rac1

    PubMed Central

    D'Amico, Gabriela; Jones, Dylan T.; Nye, Emma; Sapienza, Karen; Ramjuan, Antoine R.; Reynolds, Louise E.; Robinson, Stephen D.; Kostourou, Vassiliki; Martinez, Dolores; Aubyn, Deborah; Grose, Richard; Thomas, Gareth J.; Spencer-Dene, Bradley; Zicha, Daniel; Davies, Derek; Tybulewicz, Victor; Hodivala-Dilke, Kairbaan M.

    2009-01-01

    Sprouting angiogenesis and lymphatic-blood vessel segregation both involve the migration of endothelial cells, but the precise migratory molecules that govern the decision of blood vascular endothelial cells to segregate into lymphatic vasculature are unknown. Here, we deleted endothelial Rac1 in mice (Tie1-Cre+;Rac1fl/fl) and revealed, unexpectedly, that whereas blood vessel morphology appeared normal, lymphatic-blood vessel separation was impaired, with corresponding edema, haemorrhage and embryonic lethality. Importantly, normal levels of Rac1 were essential for directed endothelial cell migratory responses to lymphatic-inductive signals. Our studies identify Rac1 as a crucial part of the migratory machinery required for endothelial cells to separate and form lymphatic vasculature. PMID:19906871

  3. The chemokine receptors ACKR2 and CCR2 reciprocally regulate lymphatic vessel density

    PubMed Central

    Lee, Kit M; Danuser, Renzo; Stein, Jens V; Graham, Delyth; Nibbs, Robert JB; Graham, Gerard J

    2014-01-01

    Macrophages regulate lymphatic vasculature development; however, the molecular mechanisms regulating their recruitment to developing, and adult, lymphatic vascular sites are not known. Here, we report that resting mice deficient for the inflammatory chemokine-scavenging receptor, ACKR2, display increased lymphatic vessel density in a range of tissues under resting and regenerating conditions. This appears not to alter dendritic cell migration to draining lymph nodes but is associated with enhanced fluid drainage from peripheral tissues and thus with a hypotensive phenotype. Examination of embryonic skin revealed that this lymphatic vessel density phenotype is developmentally established. Further studies indicated that macrophages and the inflammatory CC-chemokine CCL2, which is scavenged by ACKR2, are associated with this phenotype. Accordingly, mice deficient for the CCL2 signalling receptor, CCR2, displayed a reciprocal phenotype of reduced lymphatic vessel density. Further examination revealed that proximity of pro-lymphangiogenic macrophages to developing lymphatic vessel surfaces is increased in ACKR2-deficient mice and reduced in CCR2-deficient mice. Therefore, these receptors regulate vessel density by reciprocally modulating pro-lymphangiogenic macrophage recruitment, and proximity, to developing, resting and regenerating lymphatic vessels. PMID:25271254

  4. A transgenic Prox1-Cre-tdTomato reporter mouse for lymphatic vessel research.

    PubMed

    Bianchi, Roberta; Teijeira, Alvaro; Proulx, Steven T; Christiansen, Ailsa J; Seidel, Catharina D; Rülicke, Thomas; Mäkinen, Taija; Hägerling, René; Halin, Cornelia; Detmar, Michael

    2015-01-01

    The lymphatic vascular system plays an active role in immune cell trafficking, inflammation and cancer spread. In order to provide an in vivo tool to improve our understanding of lymphatic vessel function in physiological and pathological conditions, we generated and characterized a tdTomato reporter mouse and crossed it with a mouse line expressing Cre recombinase under the control of the lymphatic specific promoter Prox1 in an inducible fashion. We found that the tdTomato fluorescent signal recapitulates the expression pattern of Prox1 in lymphatic vessels and other known Prox1-expressing organs. Importantly, tdTomato co-localized with the lymphatic markers Prox1, LYVE-1 and podoplanin as assessed by whole-mount immunofluorescence and FACS analysis. The tdTomato reporter was brighter than a previously established red fluorescent reporter line. We confirmed the applicability of this animal model to intravital microscopy of dendritic cell migration into and within lymphatic vessels, and to fluorescence-activated single cell analysis of lymphatic endothelial cells. Additionally, we were able to describe the early morphological changes of the lymphatic vasculature upon induction of skin inflammation. The Prox1-Cre-tdTomato reporter mouse thus shows great potential for lymphatic research.

  5. Objective assessment of blood and lymphatic vessel invasion and association with macrophage infiltration in cutaneous melanoma.

    PubMed

    Storr, Sarah J; Safuan, Sabreena; Mitra, Angana; Elliott, Faye; Walker, Christopher; Vasko, Mark J; Ho, Bernard; Cook, Martin; Mohammed, Rabab A A; Patel, Poulam M; Ellis, Ian O; Newton-Bishop, Julia A; Martin, Stewart G

    2012-04-01

    The aims of this study were to investigate the role of vascular invasion (blood and lymphatic), vessel density and the presence of tumour-associated macrophages as prognostic markers in 202 cutaneous melanoma patients. Sections of primary melanoma were stained with lymphatic-specific antibody D2-40 to assess lymphatic vessel invasion and density in intratumoural and peritumoural areas; an antibody against endothelial marker CD34 was used to determine blood vessel invasion and density, and an antibody against CD68 was used to determine macrophage counts. Immunohistochemically determined vascular invasion (combined blood and lymphatic) was compared with that determined using haematoxylin and eosin (H&E) staining. The use of immunohistochemistry increased detection of vascular invasion from 8-30% of patients, and histological exam of H&E-stained tissue was associated with a false positive rate of 64%. Lymphatic vessel invasion occurred at a much higher frequency than blood vessel invasion (27 and 4% of patients, respectively). Although immunohistochemically detected vessel invasion was significantly associated with histological markers of adverse prognosis, such as increased Breslow thickness, ulceration and mitotic rate (all P<0.001), no associations with relapse-free or overall survival were observed. High macrophage counts were significantly associated with markers of aggressive disease, such as Breslow thickness, ulceration and mitotic rate (P<0.001, P<0.001, P=0.005, respectively), and lymphatic vessel invasion and high microvessel density (P=0.002 and P=0.003, respectively). These results suggest that vascular invasion is more accurately detected using immunohistochemistry and occurs predominantly via lymphatic vessels. The association of vessel characteristics with histological characteristics of the primary melanoma provides evidence for their biological importance in melanoma, but that they were not associated with clinical outcome attests to the value of

  6. In vivo quantification of lymph viscosity and pressure in lymphatic vessels and draining lymph nodes of arthritic joints in mice

    PubMed Central

    Bouta, Echoe M; Wood, Ronald W; Brown, Edward B; Rahimi, Homaira; Ritchlin, Christopher T; Schwarz, Edward M

    2014-01-01

    Rheumatoid arthritis (RA) is a chronic inflammatory joint disease with episodic flares. In TNF-Tg mice, a model of inflammatory–erosive arthritis, the popliteal lymph node (PLN) enlarges during the pre-arthritic ‘expanding’ phase, and then ‘collapses’ with adjacent knee flare associated with the loss of the intrinsic lymphatic pulse. As the mechanisms responsible are unknown, we developed in vivo methods to quantify lymph viscosity and pressure in mice with wild-type (WT), expanding and collapsed PLN. While no differences in viscosity were detected via multiphoton fluorescence recovery after photobleaching (MP-FRAP) of injected FITC-BSA, a 32.6% decrease in lymph speed was observed in vessels afferent to collapsed PLN (P < 0.05). Direct measurement of intra-lymph node pressure (LNP) demonstrated a decrease in expanding PLN versus WT pressure (3.41 ± 0.43 vs. 6.86 ± 0.56 cmH2O; P < 0.01), which dramatically increased to 9.92 ± 1.79 cmH2O in collapsed PLN. Lymphatic pumping pressure (LPP), measured indirectly by slowly releasing a pressurized cuff occluding indocyanine green (ICG), demonstrated an increase in vessels afferent to expanding PLN versus WT (18.76 ± 2.34 vs. 11.04 ± 1.47 cmH2O; P < 0.01), which dropped to 2.61 ± 0.72 cmH2O (P < 0.001) after PLN collapse. Herein, we document the first in vivo measurements of murine lymph viscosity and lymphatic pressure, and provide evidence to support the hypothesis that lymphangiogenesis and lymphatic transport are compensatory mechanisms to prevent synovitis via increased drainage of inflamed joints. Furthermore, the decrease in lymphatic flow and loss of LPP during PLN collapse are consistent with decreased drainage from the joint during arthritic flare, and validate these biomarkers of RA progression and possibly other chronic inflammatory conditions. PMID:24421350

  7. An in situ optical imaging system for measuring lipid uptake, vessel contraction, and lymph flow in small animal lymphatic vessels

    NASA Astrophysics Data System (ADS)

    Kassis, Timothy; Weiler, Michael J.; Dixon, J. Brandon

    2012-03-01

    All dietary lipids are transported to venous circulation through the lymphatic system, yet the underlying mechanisms that regulate this process remain unclear. Understanding how the lymphatics functionally respond to changes in lipid load is important in the diagnosis and treatment of lipid and lymphatic related diseases such as obesity, hypercholesterolemia, and lymphedema. Therefore, we sought to develop an in situ imaging system to quantify and correlate lymphatic function as it relates to lipid transport. A custom-built optical set-up provides us with the capability of dual-channel imaging of both high-speed bright-field video and fluorescence simultaneously. This is achieved by dividing the light path into two optical bands. Utilizing high-speed and back-illuminated CCD cameras and post-acquisition image processing algorithms, we have the potential quantify correlations between vessel contraction, lymph flow and lipid concentration of mesenteric lymphatic vessels in situ. Local flow velocity is measured through lymphocyte tracking, vessel contraction through measurements of the vessel walls and lipid uptake through fluorescence intensity tracking of a fluorescent long chain fatty acid analogue, Bodipy FL C16. This system will prove to be an invaluable tool for both scientists studying lymphatic function in health and disease, and those investigating strategies for targeting the lymphatic system with orally delivered drugs.

  8. Podoplanin immunopositive lymphatic vessels at the implant interface in a rat model of osteoporotic fractures.

    PubMed

    Lips, Katrin Susanne; Kauschke, Vivien; Hartmann, Sonja; Thormann, Ulrich; Ray, Seemun; Kampschulte, Marian; Langheinrich, Alexander; Schumacher, Matthias; Gelinsky, Michael; Heinemann, Sascha; Hanke, Thomas; Kautz, Armin R; Schnabelrauch, Matthias; Schnettler, Reinhard; Heiss, Christian; Alt, Volker; Kilian, Olaf

    2013-01-01

    Insertion of bone substitution materials accelerates healing of osteoporotic fractures. Biodegradable materials are preferred for application in osteoporotic patients to avoid a second surgery for implant replacement. Degraded implant fragments are often absorbed by macrophages that are removed from the fracture side via passage through veins or lymphatic vessels. We investigated if lymphatic vessels occur in osteoporotic bone defects and whether they are regulated by the use of different materials. To address this issue osteoporosis was induced in rats using the classical method of bilateral ovariectomy and additional calcium and vitamin deficient diet. In addition, wedge-shaped defects of 3, 4, or 5 mm were generated in the distal metaphyseal area of femur via osteotomy. The 4 mm defects were subsequently used for implantation studies where bone substitution materials of calcium phosphate cement, composites of collagen and silica, and iron foams with interconnecting pores were inserted. Different materials were partly additionally functionalized by strontium or bisphosphonate whose positive effects in osteoporosis treatment are well known. The lymphatic vessels were identified by immunohistochemistry using an antibody against podoplanin. Podoplanin immunopositive lymphatic vessels were detected in the granulation tissue filling the fracture gap, surrounding the implant and growing into the iron foam through its interconnected pores. Significant more lymphatic capillaries were counted at the implant interface of composite, strontium and bisphosphonate functionalized iron foam. A significant increase was also observed in the number of lymphatics situated in the pores of strontium coated iron foam. In conclusion, our results indicate the occurrence of lymphatic vessels in osteoporotic bone. Our results show that lymphatic vessels are localized at the implant interface and in the fracture gap where they might be involved in the removal of lymphocytes, macrophages

  9. Podoplanin Immunopositive Lymphatic Vessels at the Implant Interface in a Rat Model of Osteoporotic Fractures

    PubMed Central

    Lips, Katrin Susanne; Kauschke, Vivien; Hartmann, Sonja; Thormann, Ulrich; Ray, Seemun; Kampschulte, Marian; Langheinrich, Alexander; Schumacher, Matthias; Gelinsky, Michael; Heinemann, Sascha; Hanke, Thomas; Kautz, Armin R.; Schnabelrauch, Matthias; Schnettler, Reinhard; Heiss, Christian; Alt, Volker; Kilian, Olaf

    2013-01-01

    Insertion of bone substitution materials accelerates healing of osteoporotic fractures. Biodegradable materials are preferred for application in osteoporotic patients to avoid a second surgery for implant replacement. Degraded implant fragments are often absorbed by macrophages that are removed from the fracture side via passage through veins or lymphatic vessels. We investigated if lymphatic vessels occur in osteoporotic bone defects and whether they are regulated by the use of different materials. To address this issue osteoporosis was induced in rats using the classical method of bilateral ovariectomy and additional calcium and vitamin deficient diet. In addition, wedge-shaped defects of 3, 4, or 5 mm were generated in the distal metaphyseal area of femur via osteotomy. The 4 mm defects were subsequently used for implantation studies where bone substitution materials of calcium phosphate cement, composites of collagen and silica, and iron foams with interconnecting pores were inserted. Different materials were partly additionally functionalized by strontium or bisphosphonate whose positive effects in osteoporosis treatment are well known. The lymphatic vessels were identified by immunohistochemistry using an antibody against podoplanin. Podoplanin immunopositive lymphatic vessels were detected in the granulation tissue filling the fracture gap, surrounding the implant and growing into the iron foam through its interconnected pores. Significant more lymphatic capillaries were counted at the implant interface of composite, strontium and bisphosphonate functionalized iron foam. A significant increase was also observed in the number of lymphatics situated in the pores of strontium coated iron foam. In conclusion, our results indicate the occurrence of lymphatic vessels in osteoporotic bone. Our results show that lymphatic vessels are localized at the implant interface and in the fracture gap where they might be involved in the removal of lymphocytes, macrophages

  10. Absence of lymphatic vessels in human dental pulp: a morphological study.

    PubMed

    Gerli, Renato; Secciani, Ilaria; Sozio, Francesca; Rossi, Antonella; Weber, Elisabetta; Lorenzini, Guido

    2010-04-01

    Few and controversial data are available in the literature regarding the presence of lymphatic vessels in the human dental pulp. The present study was designed to examine morphologically the existence of a lymph drainage system in human dental pulp. Human dental pulp and skin sections were immunohistochemically stained with specific antibodies for lymphatic endothelium (D2-40, LYVE-1, VEGFR-3 [vascular endothelial growth factor receptor-3], and Prox-1), with the pan-endothelial markers CD31 and von Willebrand factor (vWF), and with the blood-specific marker CD34. Several blood vessels were identified in human pulps and skin. Lymphatic vessels were found in all human skin samples but in none of the pulps examined. Western blotting performed on human dermis and on pulps treated with collagenase (to remove odontoblasts) confirmed these results. Transmission electron microscopy indicated that vessels which, by light microscopy, appeared to be initial lymphatic vessels had no anchoring filaments or discontinuous basement membrane, both of which are typical ultrastructural characteristics of lymphatic vessels. These results suggest that under normal conditions human dental pulp does not contain true lymphatic vessels. The various theories about dental pulp interstitial fluid circulation should be revised accordingly.

  11. Functional adaptation of bovine mesenteric lymphatic vessels to mesenteric venous hypertension

    PubMed Central

    Criscione, John C.; Kotiya, Akhilesh; Dongaonkar, Ranjeet M.; Hardy, Joanne; Wilson, Emily; Gashev, Anatoliy A.; Laine, Glen A.; Stewart, Randolph H.

    2014-01-01

    Lymph flow is the primary mechanism for returning interstitial fluid to the blood circulation. Currently, the adaptive response of lymphatic vessels to mesenteric venous hypertension is not known. This study sought to determine the functional responses of postnodal mesenteric lymphatic vessels. We surgically occluded bovine mesenteric veins to create mesenteric venous hypertension to elevate mesenteric lymph flow. Three days after surgery, postnodal mesenteric lymphatic vessels from mesenteric venous hypertension (MVH; n = 7) and sham surgery (Sham; n = 6) group animals were evaluated and compared. Contraction frequency (MVH: 2.98 ± 0.75 min−1; Sham: 5.42 ± 0.81 min−1) and fractional pump flow (MVH: 1.14 ± 0.30 min−1; Sham: 2.39 ± 0.32 min−1) were significantly lower in the venous occlusion group. These results indicate that postnodal mesenteric lymphatic vessels adapt to mesenteric venous hypertension by reducing intrinsic contractile activity. PMID:24671245

  12. Functional adaptation of bovine mesenteric lymphatic vessels to mesenteric venous hypertension.

    PubMed

    Quick, Christopher M; Criscione, John C; Kotiya, Akhilesh; Dongaonkar, Ranjeet M; Hardy, Joanne; Wilson, Emily; Gashev, Anatoliy A; Laine, Glen A; Stewart, Randolph H

    2014-06-15

    Lymph flow is the primary mechanism for returning interstitial fluid to the blood circulation. Currently, the adaptive response of lymphatic vessels to mesenteric venous hypertension is not known. This study sought to determine the functional responses of postnodal mesenteric lymphatic vessels. We surgically occluded bovine mesenteric veins to create mesenteric venous hypertension to elevate mesenteric lymph flow. Three days after surgery, postnodal mesenteric lymphatic vessels from mesenteric venous hypertension (MVH; n = 7) and sham surgery (Sham; n = 6) group animals were evaluated and compared. Contraction frequency (MVH: 2.98 ± 0.75 min(-1); Sham: 5.42 ± 0.81 min(-1)) and fractional pump flow (MVH: 1.14 ± 0.30 min(-1); Sham: 2.39 ± 0.32 min(-1)) were significantly lower in the venous occlusion group. These results indicate that postnodal mesenteric lymphatic vessels adapt to mesenteric venous hypertension by reducing intrinsic contractile activity.

  13. Pump function curve shape for a model lymphatic vessel.

    PubMed

    Bertram, C D; Macaskill, C; Moore, J E

    2016-07-01

    The transport capacity of a contractile segment of lymphatic vessel is defined by its pump function curve relating mean flow-rate and adverse pressure difference. Numerous system characteristics affect curve shape and the magnitude of the generated flow-rates and pressures. Some cannot be varied experimentally, but their separate and interacting effects can be systematically revealed numerically. This paper explores variations in the rate of change of active tension and the form of the relation between active tension and muscle length, factors not known from experiment to functional precision. Whether the pump function curve bends toward or away from the origin depends partly on the curvature of the passive pressure-diameter relation near zero transmural pressure, but rather more on the form of the relation between active tension and muscle length. A pump function curve bending away from the origin defines a well-performing pump by maximum steady output power. This behaviour is favoured by a length/active-tension relationship which sustains tension at smaller lengths. Such a relationship also favours high peak mechanical efficiency, defined as output power divided by the input power obtained from the lymphangion diameter changes and active-tension time-course. The results highlight the need to pin down experimentally the form of the length/active-tension relationship. PMID:27185045

  14. Visualisation of blood and lymphatic vessels with increasing exposure time of the detector

    NASA Astrophysics Data System (ADS)

    Kalchenko, V. V.; Kuznetsov, Yu L.; Meglinski, I. V.

    2013-07-01

    We describe the laser speckle contrast method for simultaneous noninvasive imaging of blood and lymphatic vessels of living organisms, based on increasing detector exposure time. In contrast to standard methods of fluorescent angiography, this technique of vascular bed imaging and lymphatic and blood vessel demarcation does not employ toxic fluorescent markers. The method is particularly promising with respect to the physiology of the cardiovascular system under in vivo conditions.

  15. Visualisation of blood and lymphatic vessels with increasing exposure time of the detector

    SciTech Connect

    Kalchenko, V V; Kuznetsov, Yu L; Meglinski, I V

    2013-07-31

    We describe the laser speckle contrast method for simultaneous noninvasive imaging of blood and lymphatic vessels of living organisms, based on increasing detector exposure time. In contrast to standard methods of fluorescent angiography, this technique of vascular bed imaging and lymphatic and blood vessel demarcation does not employ toxic fluorescent markers. The method is particularly promising with respect to the physiology of the cardiovascular system under in vivo conditions. (laser applications in biology and medicine)

  16. Role of lymphatic vessels in tumor immunity: passive conduits or active participants?

    PubMed

    Lund, Amanda W; Swartz, Melody A

    2010-09-01

    Research in lymphatic biology and cancer immunology may soon intersect as emerging evidence implicates the lymphatics in the progression of chronic inflammation and autoimmunity as well as in tumor metastasis and immune escape. Like the blood vasculature, the lymphatic system comprises a highly dynamic conduit system that regulates fluid homeostasis, antigen transport and immune cell trafficking, which all play important roles in the progression and resolution of inflammation, autoimmune diseases, and cancer. This review presents emerging evidence that lymphatic vessels are active modulators of immunity, perhaps fine-tuning the response to adjust the balance between peripheral tolerance and immunity. This suggests that the tumor-associated lymphatic vessels and draining lymph node may be important in tumor immunity which in turn governs metastasis.

  17. Label-free optical imaging of lymphatic vessels within tissue beds in vivo

    PubMed Central

    Yousefi, Siavash; Zhi, Zhongwei; Wang, Ruikang K.

    2015-01-01

    Lymphatic vessels are a part of circulatory system in vertebrates that maintain tissue fluid homeostasis and drain excess fluid and large cells that cannot easily find their way back into venous system. Due to the lack of non-invasive monitoring tools, lymphatic vessels are known as forgotten circulation. However, lymphatic system plays an important role in diseases such as cancer and inflammatory conditions. In this paper, we start to briefly review the current existing methods for imaging lymphatic vessels, mostly involving dye/targeting cell injection. We then show the capability of optical coherence tomography (OCT) for label-free non-invasive in vivo imaging of lymph vessels and nodes. One of the advantages of using OCT over other imaging modalities is its ability to assess label-free blood flow perfusion that can be simultaneously observed along with lymphatic vessels for imaging the microcirculatory system within tissue beds. Imaging the microcirculatory system including blood and lymphatic vessels can be utilized for imaging and better understanding pathologic mechanisms and treatment technique development in some critical diseases such as inflammation, malignant cancer angiogenesis and metastasis. PMID:25642129

  18. CCR7 and IRF4-dependent dendritic cells regulate lymphatic collecting vessel permeability

    PubMed Central

    Ivanov, Stoyan; Scallan, Joshua P.; Kim, Ki-Wook; Werth, Kathrin; Johnson, Michael W.; Saunders, Brian T.; Wang, Peter L.; Kuan, Emma L.; Straub, Adam C.; Ouhachi, Melissa; Weinstein, Erica G.; Williams, Jesse W.; Briseño, Carlos; Colonna, Marco; Isakson, Brant E.; Gautier, Emmanuel L.; Förster, Reinhold; Davis, Michael J.; Zinselmeyer, Bernd H.

    2016-01-01

    Lymphatic collecting vessels direct lymph into and from lymph nodes (LNs) and can become hyperpermeable as the result of a previous infection. Enhanced permeability has been implicated in compromised immunity due to reduced flow of lymph and immune cells to LNs, which are the primary site of antigen presentation to T cells. Presently, very little is known about the molecular signals that affect lymphatic collecting vessel permeability. Here, we have shown that lymphatic collecting vessel permeability is controlled by CCR7 and that the chronic hyperpermeability of collecting vessels observed in Ccr7–/– mice is followed by vessel fibrosis. Reexpression of CCR7 in DCs, however, was sufficient to reverse the development of such fibrosis. IFN regulatory factor 4–positive (IRF4+) DCs constitutively interacted with collecting lymphatics, and selective ablation of this DC subset in Cd11c-Cre Irf4fl/fl mice also rendered lymphatic collecting vessels hyperpermeable and fibrotic. Together, our data reveal that CCR7 plays multifaceted roles in regulating collecting vessel permeability and fibrosis, with one of the key players being IRF4-dependent DCs. PMID:26999610

  19. Itching for answers: how histamine relaxes lymphatic vessels.

    PubMed

    Scallan, Joshua P; Davis, Michael J

    2014-10-01

    In the current issue of Microcirculation, studies by Kurtz et al. and Nizamutdinova et al. together provide new evidence supporting a role for histamine as an endothelial-derived molecule that inhibits lymphatic muscle contraction. In particular, Nizamutdinova et al. show that the effects of flow-induced shear stress on lymphatic endothelium are mediated by both nitric oxide and histamine, since only blockade of both prevents contraction strength and frequency from being altered by flow. Separately, Kurtz et al. used confocal microscopy to determine a preferential expression of histamine receptors on the lymphatic endothelium and demonstrated that histamine applied to spontaneously contracting collecting lymphatics inhibits contractions. Previous studies disagreed on whether histamine stimulates or inhibits lymphatic contractions, but also used differing concentrations, species, and preparations. Together these new reports shed light on how histamine acts within the lymphatic vasculature, but also raise important questions about the cell type on which histamine exerts its effects and the signaling pathways involved. This editorial briefly discusses the contribution of each study and its relevance to lymphatic biology.

  20. Immunohistochemical identification of lymphatic vessels in the periodontium of equine cheek teeth.

    PubMed

    Staszyk, Carsten; Duesterdieck, Katja F; Gasse, Hagen; Bienert, Astrid

    2005-12-01

    Immunohistochemical detection of lymphatic capillaries was performed in the periodontium of maxillary and mandibular cheek teeth from 6 horses (aged 3-23 years). Tissue sections of the periodontium were taken at 4 different horizontal levels along the long axis of the tooth. The specimens were processed for immunoreaction with anti-Prox1, in order to distinguish lymphatic endothelium from blood vascular endothelium. Lymphatic vessels were detected in all periodontal tissues except for the dental cementum. Lymphatic capillaries were most densely distributed in the gingiva compared to other tissues of the periodontium. Lymphatic capillaries were found most consistently in samples taken from the gingival and subgingival regions in all horses examined. Within these levels, the gingiva as well as the spongiosa of the maxillary and mandibular bone had the greatest incidence of lymphatic vessels. Considering the distinct distribution of the lymphatic capillaries in the periodontium of the maxillary and mandibular cheek teeth, two complementary lymphatic drainage pathways are proposed: (1) superficial lymph drainage via the gingiva, emptying into the mandibular lymph nodes; (2) deep lymph drainage via the mandibular and maxillary spongiosa, emptying into the mandibular and retropharyngeal lymph nodes, respectively.

  1. Contractile activity of lymphatic vessels is altered in the TNBS model of guinea pig ileitis.

    PubMed

    Wu, Theresa F; Carati, Colin J; Macnaughton, Wallace K; von der Weid, Pierre-Yves

    2006-10-01

    The ability of the lymphatic system to actively remove fluid from the interstitium is critical to the resolution of edema. The response of the lymphatics to inflammatory situations is poorly studied, so we examined mesenteric lymphatic contractile activity in the 2,4,6-trinitrobenzenesulfonic acid (TNBS) model of guinea pig ileitis, a well-accepted animal model of intestinal inflammation, by videomicroscopy in vivo and in vitro 1, 3, and 6 days after induction of ileitis. Lymphatic function (diameter, constriction frequency, amplitude of constrictions, and calculated stroke volume and lymph flow rate) of isolated vessels from TNBS-treated guinea pigs were impaired compared with sham-treated controls. The dysfunction was well correlated with the degree of inflammation, with differences reaching significance (P < 0.05) at the highest inflammation-induced damage observed at day 3. In vivo, significantly fewer lymphatics exhibited spontaneous constrictions in TNBS-treated than sham-treated animals. Cyclooxygenase (COX) metabolites were suggested to be involved in this lymphatic dysfunction, since application of nonselective COX inhibitor (10 microM indomethacin) or a combination of COX-1 and COX-2 inhibitors (1 microM SC-560 and 10 microM celecoxib) markedly increased constriction frequency or induced them in lymphatics from TNBS-treated animals in vivo and in vitro. The present results demonstrate that lymphatic contractile function is altered in TNBS-induced ileitis and suggest a role for prostanoids in the lymphatic dysfunction.

  2. Effects of dynamic shear and transmural pressure on wall shear stress sensitivity in collecting lymphatic vessels.

    PubMed

    Kornuta, Jeffrey A; Nepiyushchikh, Zhanna; Gasheva, Olga Y; Mukherjee, Anish; Zawieja, David C; Dixon, J Brandon

    2015-11-01

    Given the known mechanosensitivity of the lymphatic vasculature, we sought to investigate the effects of dynamic wall shear stress (WSS) on collecting lymphatic vessels while controlling for transmural pressure. Using a previously developed ex vivo lymphatic perfusion system (ELPS) capable of independently controlling both transaxial pressure gradient and average transmural pressure on an isolated lymphatic vessel, we imposed a multitude of flow conditions on rat thoracic ducts, while controlling for transmural pressure and measuring diameter changes. By gradually increasing the imposed flow through a vessel, we determined the WSS at which the vessel first shows sign of contraction inhibition, defining this point as the shear stress sensitivity of the vessel. The shear stress threshold that triggered a contractile response was significantly greater at a transmural pressure of 5 cmH2O (0.97 dyne/cm(2)) than at 3 cmH2O (0.64 dyne/cm(2)). While contraction frequency was reduced when a steady WSS was applied, this inhibition was reversed when the applied WSS oscillated, even though the mean wall shear stresses between the conditions were not significantly different. When the applied oscillatory WSS was large enough, flow itself synchronized the lymphatic contractions to the exact frequency of the applied waveform. Both transmural pressure and the rate of change of WSS have significant impacts on the contractile response of lymphatic vessels to flow. Specifically, time-varying shear stress can alter the inhibition of phasic contraction frequency and even coordinate contractions, providing evidence that dynamic shear could play an important role in the contractile function of collecting lymphatic vessels.

  3. The Role of the Mesentery in Crohn's Disease: The Contributions of Nerves, Vessels, Lymphatics, and Fat to the Pathogenesis and Disease Course.

    PubMed

    Li, Yi; Zhu, Weiming; Zuo, Lugen; Shen, Bo

    2016-06-01

    Crohn's disease (CD) is a complex gastrointestinal disorder involving multiple levels of cross talk between the immunological, neural, vascular, and endocrine systems. The current dominant theory in CD is based on the unidirectional axis of dysbiosis-innate immunity-adaptive immunity-mesentery-body system. Emerging clinical evidence strongly suggests that the axis be bidirectional. The morphologic and/or functional abnormalities in the mesenteric structures likely contribute to the disease progression of CD, to a less extent the disease initiation. In addition to adipocytes, mesentery contains nerves, blood vessels, lymphatics, stromal cells, and fibroblasts. By the secretion of adipokines that have endocrine functions, the mesenteric fat tissue exerts its activity in immunomodulation mainly through response to afferent signals, neuropeptides, and functional cytokines. Mesenteric nerves are involved in the pathogenesis and prognosis of CD mainly through neuropeptides. In addition to angiogenesis observed in CD, lymphatic obstruction, remodeling, and impaired contraction maybe a cause and consequence of CD. Lymphangiogenesis and angiogenesis play a concomitant role in the progress of chronic intestinal inflammation. Finally, the interaction between neuropeptides, adipokines, and vascular and lymphatic endothelia leads to adipose tissue remodeling, which makes the mesentery an active participator, not a bystander, in the disease initiation and precipitation CD. The identification of the role of mesentery, including the structure and function of mesenteric nerves, vessels, lymphatics, and fat, in the intestinal inflammation in CD has important implications in understanding its pathogenesis and clinical management. PMID:27167572

  4. Determinants of valve gating in collecting lymphatic vessels from rat mesentery.

    PubMed

    Davis, Michael J; Rahbar, Elaheh; Gashev, Anatoliy A; Zawieja, David C; Moore, James E

    2011-07-01

    Secondary lymphatic valves are essential for minimizing backflow of lymph and are presumed to gate passively according to the instantaneous trans-valve pressure gradient. We hypothesized that valve gating is also modulated by vessel distention, which could alter leaflet stiffness and coaptation. To test this hypothesis, we devised protocols to measure the small pressure gradients required to open or close lymphatic valves and determine if the gradients varied as a function of vessel diameter. Lymphatic vessels were isolated from rat mesentery, cannulated, and pressurized using a servo-control system. Detection of valve leaflet position simultaneously with diameter and intraluminal pressure changes in two-valve segments revealed the detailed temporal relationships between these parameters during the lymphatic contraction cycle. The timing of valve movements was similar to that of cardiac valves, but only when lymphatic vessel afterload was elevated. The pressure gradients required to open or close a valve were determined in one-valve segments during slow, ramp-wise pressure elevation, either from the input or output side of the valve. Tests were conducted over a wide range of baseline pressures (and thus diameters) in passive vessels as well as in vessels with two levels of imposed tone. Surprisingly, the pressure gradient required for valve closure varied >20-fold (0.1-2.2 cmH(2)O) as a passive vessel progressively distended. Similarly, the pressure gradient required for valve opening varied sixfold with vessel distention. Finally, our functional evidence supports the concept that lymphatic muscle tone exerts an indirect effect on valve gating.

  5. Angiopoietin-4 increases permeability of blood vessels and promotes lymphatic dilation.

    PubMed

    Kesler, Cristina T; Pereira, Ethel R; Cui, Cheryl H; Nelson, Gregory M; Masuck, David J; Baish, James W; Padera, Timothy P

    2015-09-01

    The angiopoietin (Ang) ligands are potential therapeutic targets for lymphatic related diseases, which include lymphedema and cancer. Ang-1 and Ang-2 functions are established, but those of Ang-4 are poorly understood. We used intravital fluorescence microscopy to characterize Ang-4 actions on T241 murine fibrosarcoma-associated vessels in mice. The diameters of lymphatic vessels draining Ang-4- or VEGF-C (positive control)-expressing tumors increased to 123 and 135 μm, respectively, and parental, mock-transduced (negative controls) and tumors expressing Ang-1 or Ang-2 remained at baseline (∼60 μm). Ang-4 decreased human dermal lymphatic endothelial cell (LEC) monolayer permeability by 27% while increasing human dermal blood endothelial cell (BEC) monolayer permeability by 200%. In vivo, Ang-4 stimulated a 4.5-fold increase in tumor-associated blood vessel permeability compared with control when measured using intravital quantitative multiphoton microscopy. Ang-4 activated receptor signaling in both LECs and BECs, evidenced by tyrosine kinase with Ig and endothelial growth factor homology domains-2 (TIE2) receptor, protein kinase B, and Erk1,2 phosphorylation detectable by immunoblotting. These data suggest that Ang-4 actions are mediated through cell-type-specific networks and that lymphatic vessel dilation occurs secondarily to increased vascular leakage. Ang-4 also promoted survival of LECs. Thus, blocking Ang-4 may prune the draining lymphatic vasculature and decrease interstitial fluid pressure (IFP) by reducing vascular permeability.

  6. Microneedles for the Noninvasive Structural and Functional Assessment of Dermal Lymphatic Vessels.

    PubMed

    Brambilla, Davide; Proulx, Steven T; Marschalkova, Patrizia; Detmar, Michael; Leroux, Jean-Christophe

    2016-02-24

    The medical and scientific communities' interest in the lymphatic system has been growing rapidly in recent years. It has become evident that the lymphatic system is much more than simply a homeostasis controller and that it plays key roles in several pathological conditions. This work describes the identification of the optimal combination of poly(N-vinylpyrrolidone) and a near-infrared dye (indocyanine green) for the manufacturing of soluble microneedles and their application to the imaging of the lymphatic system. Upon application to the skin, the microneedle-bearing indocyanine green is delivered in the dermal layer, where the lymphatic vessels are abundant. The draining lymphatics can then be visualized and the clearance kinetics from the administration site simply determined using a near-infrared camera. This painless functional "tattooing" procedure can be used for quantitative assessment of the dermal lymphatic function in several dermal conditions and treatment-response evaluations. The two components of these microneedles are extensively used in routine medical care, potentially leading to rapid clinical translation. Moreover, this procedure may have a significant impact on preclinical lymphatic studies.

  7. Absence of lymphatic vessels in the dog dental pulp: an immunohistochemical study.

    PubMed

    Martin, Anna; Gasse, Hagen; Staszyk, Carsten

    2010-11-01

    In spite of numerous investigations it has not been precisely determined whether lymphatic vessels are present in the dental pulp of dogs. Therefore, this study attempted a specific immunohistochemical detection of lymphatic endothelium. The canine teeth of 19 healthy beagle dogs were dissected into three segments (apical, intermediate and occlusal). After decalcification, specimens were embedded in paraffin wax and histologic cross-sections were stained immunohistochemically using a reliable antibody (anti-Prox-1) against the homeobox transcription factor Prox-1, which is located within the nucleus of lymphatic endothelium. Anti-Prox-1 reacted positively with canine control tissues (lymph nodes, gingiva, nasal mucosa), but showed no staining in tissue sections of the dental pulp. The dog dental pulp contained no vascular structures lined with lymphatic endothelium. This suggests that drainage of interstitial fluid makes use of other routes, i.e. extravascular pathways.

  8. Differential Distribution of Blood and Lymphatic Vessels in the Murine Cornea

    PubMed Central

    Ecoiffier, Tatiana; Yuen, Don

    2010-01-01

    Purpose. Because of its unique characteristics, the cornea has been widely used for blood and lymphatic vessel research. However, whether limbal or corneal vessels are evenly distributed under normal or inflamed conditions has never been studied. The purpose of this study was to investigate this question and to examine whether and how the distribution patterns change during corneal inflammatory lymphangiogenesis (LG) and hemangiogenesis (HG). Methods. Corneal inflammatory LG and HG were induced in two most commonly used mouse strains, BALB/c and C57BL/6 (6–8 weeks of age), by a standardized two-suture placement model. Oriented flat-mount corneas together with the limbal tissues were used for immunofluorescence microscope studies. Blood and lymphatic vessels under normal and inflamed conditions were analyzed and quantified to compare their distributions. Results. The data demonstrate, for the first time, greater distribution of both blood and lymphatic vessels in the nasal side in normal murine limbal areas. This nasal-dominant pattern was maintained during corneal inflammatory LG, whereas it was lost for HG. Conclusions. Blood and lymphatic vessels are not evenly distributed in normal limbal areas. Furthermore, corneal LG and HG respond differently to inflammatory stimuli. These new findings will shed some light on corneal physiology and pathogenesis and on the development of experimental models and therapeutic strategies for corneal diseases. PMID:20019372

  9. Monitoring the primo vascular system in lymphatic vessels by using window chambers.

    PubMed

    Kim, Jungdae; Kim, Dong-Hyun; Jung, Sharon Jiyoon; Gil, Hyun-Ji; Yoon, Seung Zhoo; Kim, Young-Il; Soh, Kwang-Sup

    2016-04-01

    This study aims to develop a window chamber system in the skin of rats and to monitor the primo vascular system (PVS) inside the lymphatic vessels along the superficial epigastric vessels. The PVS in lymphatic vessels has been observed through many experiments under in vivo conditions, but monitoring the in vivo PVS in situ inside lymphatic vessels for a long time is difficult. To overcome the obstacles, we adapted the window chamber system for monitoring the PVS and Alcian blue (AB) staining dye solution for the contrast agent. The lymphatic vessels in the skin on the lateral side of the body, connecting the inguinal lymph nodes to the axillary lymph nodes, were the targets for setting the window system. After AB had been injected into the inguinal lymph nodes with a glass capillary, the morphological changes of the stained PVS were monitored through the window system for up to twenty hours, and the changes in the AB intensity in the PVS were quantified by using image processing. The results and histological images are presented in this study.

  10. Monitoring the primo vascular system in lymphatic vessels by using window chambers.

    PubMed

    Kim, Jungdae; Kim, Dong-Hyun; Jung, Sharon Jiyoon; Gil, Hyun-Ji; Yoon, Seung Zhoo; Kim, Young-Il; Soh, Kwang-Sup

    2016-04-01

    This study aims to develop a window chamber system in the skin of rats and to monitor the primo vascular system (PVS) inside the lymphatic vessels along the superficial epigastric vessels. The PVS in lymphatic vessels has been observed through many experiments under in vivo conditions, but monitoring the in vivo PVS in situ inside lymphatic vessels for a long time is difficult. To overcome the obstacles, we adapted the window chamber system for monitoring the PVS and Alcian blue (AB) staining dye solution for the contrast agent. The lymphatic vessels in the skin on the lateral side of the body, connecting the inguinal lymph nodes to the axillary lymph nodes, were the targets for setting the window system. After AB had been injected into the inguinal lymph nodes with a glass capillary, the morphological changes of the stained PVS were monitored through the window system for up to twenty hours, and the changes in the AB intensity in the PVS were quantified by using image processing. The results and histological images are presented in this study. PMID:27446651

  11. Monitoring the primo vascular system in lymphatic vessels by using window chambers

    PubMed Central

    Kim, Jungdae; Kim, Dong-Hyun; Jung, Sharon Jiyoon; Gil, Hyun-Ji; Yoon, Seung Zhoo; Kim, Young-Il; Soh, Kwang-Sup

    2016-01-01

    This study aims to develop a window chamber system in the skin of rats and to monitor the primo vascular system (PVS) inside the lymphatic vessels along the superficial epigastric vessels. The PVS in lymphatic vessels has been observed through many experiments under in vivo conditions, but monitoring the in vivo PVS in situ inside lymphatic vessels for a long time is difficult. To overcome the obstacles, we adapted the window chamber system for monitoring the PVS and Alcian blue (AB) staining dye solution for the contrast agent. The lymphatic vessels in the skin on the lateral side of the body, connecting the inguinal lymph nodes to the axillary lymph nodes, were the targets for setting the window system. After AB had been injected into the inguinal lymph nodes with a glass capillary, the morphological changes of the stained PVS were monitored through the window system for up to twenty hours, and the changes in the AB intensity in the PVS were quantified by using image processing. The results and histological images are presented in this study. PMID:27446651

  12. VEGFR signaling during lymphatic vascular development: From progenitor cells to functional vessels.

    PubMed

    Secker, Genevieve A; Harvey, Natasha L

    2015-03-01

    Lymphatic vessels are an integral component of the cardiovascular system, serving important roles in fluid homeostasis, lipid absorption, and immune cell trafficking. Defining the mechanisms by which the lymphatic vasculature is constructed and remodeled into a functional vascular network not only provides answers to fascinating biological questions, but is fundamental to understanding how lymphatic vessel growth and development goes awry in human pathologies. While long recognized as dysfunctional in lymphedema and exploited as a route of tumor metastasis, recent work has highlighted important roles for lymphatic vessels in modulating immune responses, regulating salt-sensitive hypertension and important for lung inflation at birth. Substantial progress in our understanding of the signaling pathways important for development and morphogenesis of the lymphatic vasculature has been made in recent years. Here, we review advances in our knowledge of the best characterized of these signaling pathways, that involving the vascular endothelial growth factor (VEGF) family members VEGF-C and VEGF-D, together with their receptors VEGFR2 and VEGFR3. Recent work has defined multiple levels at which signal transduction by means of this key axis is regulated; these include control of ligand processing and bioavailability, modulation of receptor activation by interacting proteins, and regulation of receptor endocytosis and trafficking.

  13. Interaction of rat tumor cells with blood vessels and lymphatics of the avian chorioallantoic membrane.

    PubMed

    Papoutsi, M; Sleeman, J P; Wilting, J

    2001-10-15

    It has generally been assumed that tumors do not induce lymphangiogenesis and only very recently animal models have been presented showing tumor-induced lymphangiogenesis. We have grown two types of rat tumor cells, 10AS pancreatic carcinoma and C6 glioma cells, on the chorioallantoic membrane (CAM) of chick and quail embryos. The suspended tumor cells rapidly formed solid tumors which invaded the CAM and were vascularized by CAM vessels. When grown on the CAM of quail embryos intratumoral endothelial cells could be specifically stained with the QH1 antibody. In C6 gliomas the vascular pattern was more regular than in 10AS carcinomas. The vessels often grew radially into the glioma and many of them were invested by smooth muscle alpha-actin-positive periendothelial cells. Lymphatics, which were identified by vascular endothelial growth factor receptor-3 (VEGFR-3) in situ hybridization were absent from C6 gliomas, although a weak expression of the lymphangiogenic growth factor, VEGF-C, could be detected in the C6 cells by Northern blot analysis. In contrast, 10AS cells, which expressed high levels of VEGF-C, induced ingrowth of lymphatics into the tumors, with BrdU-labeling rates of about 9% of lymphatic endothelial cells. Our studies demonstrate the heterogeneity of interactions of tumor cells with blood vessels and lymphatics and show that sufficient quantities and/or quality of lymphangiogenic growth factors are crucial for the induction of lymphatics in tumors. PMID:11596155

  14. VEGF-C is required for intestinal lymphatic vessel maintenance and lipid absorption

    PubMed Central

    Nurmi, Harri; Saharinen, Pipsa; Zarkada, Georgia; Zheng, Wei; Robciuc, Marius R; Alitalo, Kari

    2015-01-01

    Vascular endothelial growth factor C (VEGF-C) binding to its tyrosine kinase receptor VEGFR-3 drives lymphatic vessel growth during development and in pathological processes. Although the VEGF-C/VEGFR-3 pathway provides a target for treatment of cancer and lymphedema, the physiological functions of VEGF-C in adult vasculature are unknown. We show here that VEGF-C is necessary for perinatal lymphangiogenesis, but required for adult lymphatic vessel maintenance only in the intestine. Following Vegfc gene deletion in adult mice, the intestinal lymphatic vessels, including the lacteal vessels, underwent gradual atrophy, which was aggravated when also Vegfd was deleted. VEGF-C was expressed by a subset of smooth muscle cells adjacent to the lacteals in the villus and in the intestinal wall. The Vegfc-deleted mice showed defective lipid absorption and increased fecal excretion of dietary cholesterol and fatty acids. When fed a high-fat diet, the Vegfc-deficient mice were resistant to obesity and had improved glucose metabolism. Our findings indicate that the lymphangiogenic growth factors provide trophic and dynamic regulation of the intestinal lymphatic vasculature, which could be especially important in the dietary regulation of adiposity and cholesterol metabolism. PMID:26459520

  15. GATA2 is required for lymphatic vessel valve development and maintenance

    PubMed Central

    Kazenwadel, Jan; Betterman, Kelly L.; Chong, Chan-Eng; Stokes, Philippa H.; Lee, Young K.; Secker, Genevieve A.; Agalarov, Yan; Demir, Cansaran Saygili; Lawrence, David M.; Sutton, Drew L.; Tabruyn, Sebastien P.; Miura, Naoyuki; Salminen, Marjo; Petrova, Tatiana V.; Matthews, Jacqueline M.; Hahn, Christopher N.; Scott, Hamish S.; Harvey, Natasha L.

    2015-01-01

    Heterozygous germline mutations in the zinc finger transcription factor GATA2 have recently been shown to underlie a range of clinical phenotypes, including Emberger syndrome, a disorder characterized by lymphedema and predisposition to myelodysplastic syndrome/acute myeloid leukemia (MDS/AML). Despite well-defined roles in hematopoiesis, the functions of GATA2 in the lymphatic vasculature and the mechanisms by which GATA2 mutations result in lymphedema have not been characterized. Here, we have provided a molecular explanation for lymphedema predisposition in a subset of patients with germline GATA2 mutations. Specifically, we demonstrated that Emberger-associated GATA2 missense mutations result in complete loss of GATA2 function, with respect to the capacity to regulate the transcription of genes that are important for lymphatic vessel valve development. We identified a putative enhancer element upstream of the key lymphatic transcriptional regulator PROX1 that is bound by GATA2, and the transcription factors FOXC2 and NFATC1. Emberger GATA2 missense mutants had a profoundly reduced capacity to bind this element. Conditional Gata2 deletion in mice revealed that GATA2 is required for both development and maintenance of lymphovenous and lymphatic vessel valves. Together, our data unveil essential roles for GATA2 in the lymphatic vasculature and explain why a select catalogue of human GATA2 mutations results in lymphedema. PMID:26214525

  16. Coxsackie- and adenovirus receptor (CAR) is expressed in lymphatic vessels in human skin and affects lymphatic endothelial cell function in vitro

    SciTech Connect

    Vigl, Benjamin; Zgraggen, Claudia; Rehman, Nadia; Banziger-Tobler, Nadia E.; Detmar, Michael; Halin, Cornelia

    2009-01-15

    Lymphatic vessels play an important role in tissue fluid homeostasis, intestinal fat absorption and immunosurveillance. Furthermore, they are involved in pathologic conditions, such as tumor cell metastasis and chronic inflammation. In comparison to blood vessels, the molecular phenotype of lymphatic vessels is less well characterized. Performing comparative gene expression analysis we have recently found that coxsackie- and adenovirus receptor (CAR) is significantly more highly expressed in cultured human, skin-derived lymphatic endothelial cells (LECs), as compared to blood vascular endothelial cells. Here, we have confirmed these results at the protein level, using Western blot and FACS analysis. Immunofluorescence performed on human skin confirmed that CAR is expressed at detectable levels in lymphatic vessels, but not in blood vessels. To address the functional significance of CAR expression, we modulated CAR expression levels in cultured LECs in vitro by siRNA- and vector-based transfection approaches. Functional assays performed with the transfected cells revealed that CAR is involved in distinct cellular processes in LECs, such as cell adhesion, migration, tube formation and the control of vascular permeability. In contrast, no effect of CAR on LEC proliferation was observed. Overall, our data suggest that CAR stabilizes LEC-LEC interactions in the skin and may contribute to lymphatic vessel integrity.

  17. Microcirculation-on-a-Chip: A Microfluidic Platform for Assaying Blood- and Lymphatic-Vessel Permeability

    PubMed Central

    Sato, Miwa; Sasaki, Naoki; Ato, Manabu; Hirakawa, Satoshi; Sato, Kiichi; Sato, Kae

    2015-01-01

    We developed a microfluidic model of microcirculation containing both blood and lymphatic vessels for examining vascular permeability. The designed microfluidic device harbors upper and lower channels that are partly aligned and are separated by a porous membrane, and on this membrane, blood vascular endothelial cells (BECs) and lymphatic endothelial cells (LECs) were cocultured back-to-back. At cell-cell junctions of both BECs and LECs, claudin-5 and VE-cadherin were detected. The permeability coefficient measured here was lower than the value reported for isolated mammalian venules. Moreover, our results showed that the flow culture established in the device promoted the formation of endothelial cell-cell junctions, and that treatment with histamine, an inflammation-promoting substance, induced changes in the localization of tight and adherens junction-associated proteins and an increase in vascular permeability in the microdevice. These findings indicated that both BECs and LECs appeared to retain their functions in the microfluidic coculture platform. Using this microcirculation device, the vascular damage induced by habu snake venom was successfully assayed, and the assay time was reduced from 24 h to 30 min. This is the first report of a microcirculation model in which BECs and LECs were cocultured. Because the micromodel includes lymphatic vessels in addition to blood vessels, the model can be used to evaluate both vascular permeability and lymphatic return rate. PMID:26332321

  18. Lymphatic and blood vessels in basal and triple-negative breast cancers: characteristics and prognostic significance.

    PubMed

    Mohammed, Rabab A A; Ellis, Ian O; Mahmmod, Ali M; Hawkes, E Claire; Green, Andrew R; Rakha, Emad A; Martin, Stewart G

    2011-06-01

    Basal and triple-negative breast cancer phenotypes are characterised by unfavourable biological behaviour and outcome. Although certain studies have examined their pathological and molecular profile, the vascular characteristics of lymphatic and blood vessels have not been examined. Immunohistochemical staining with podoplanin, CD34 and CD31 was used to examine lymphatic and microvessel density, as well as vascular invasion in 197 basal-like and in 99 triple-negative breast tumours and compared against 200 non-basal and 334 non-triple-negative cases. All specimens were lymph node negative. Vascular invasion was identified as blood or lymphatic vascular invasion by the differential expression of markers. All measurements were correlated with clinicopathological features and prognosis. No significant difference was detected between the basal and triple-negative groups in terms of lymphatic or microvessel density or vascular invasion. However, both the basal and the triple-negative groups showed significantly higher microvessel density than did the non-basal and non-triple-negative groups (P=0.017 and P<0.001, respectively). Unlike microvessel density, no significant difference was detected in lymphatic density between the basal or triple-negative groups compared with their respective controls. Interestingly, vascular invasion, almost entirely lymphatic invasion, was detected in 27% of the basal and in 26% of the triple-negative groups with no significant difference in comparison with control groups. In both basal and triple negatives, vascular invasion was associated with poorer survival by univariate and multivariate analyses. The 20-year overall survival rate in basal-like tumours was 55% in vascular invasion-positive cases compared with 73% in vascular invasion-negative tumours (P=0.012), and 46% in triple-negative vascular invasion-positive compared with 79% in vascular invasion-negative tumours (P=0.001). Basal-like vs non-basal-like and triple-negative vs non

  19. Human lymphatic vessel contractile activity is inhibited in vitro but not in vivo by the calcium channel blocker nifedipine

    PubMed Central

    Telinius, Niklas; Mohanakumar, Sheyanth; Majgaard, Jens; Kim, Sukhan; Pilegaard, Hans; Pahle, Einar; Nielsen, Jørn; de Leval, Marc; Aalkjaer, Christian; Hjortdal, Vibeke; Boedtkjer, Donna Briggs

    2014-01-01

    Calcium channel blockers (CCB) are widely prescribed anti-hypertensive agents. The commonest side-effect, peripheral oedema, is attributed to a larger arterial than venous dilatation causing increased fluid filtration. Whether CCB treatment is detrimental to human lymphatic vessel function and thereby exacerbates oedema formation is unknown. We observed that spontaneous lymphatic contractions in isolated human vessels (thoracic duct and mesenteric lymphatics) maintained under isometric conditions were inhibited by therapeutic concentrations (nanomolar) of the CCB nifedipine while higher than therapeutic concentrations of verapamil (micromolar) were necessary to inhibit activity. Nifedipine also inhibited spontaneous action potentials measured by sharp microelectrodes. Furthermore, noradrenaline did not elicit normal increases in lymphatic vessel tone when maximal constriction was reduced to 29.4 ± 4.9% of control in the presence of 20 nmol l−1 nifedipine. Transcripts for the L-type calcium channel gene CACNA1C were consistently detected from human thoracic duct samples examined and the CaV1.2 protein was localized by immunoreactivity to lymphatic smooth muscle cells. While human lymphatics ex vivo were highly sensitive to nifedipine, this was not apparent in vivo when nifedipine was compared to placebo in a randomized, double-blinded clinical trial: conversely, lymphatic vessel contraction frequency was increased and refill time was faster despite all subjects achieving target nifedipine plasma concentrations. We conclude that human lymphatic vessels are highly sensitive to nifedipine in vitro but that care must be taken when extrapolating in vitro observations of lymphatic vessel function to the clinical situation, as similar changes in lymphatic function were not evident in our clinical trial comparing nifedipine treatment to placebo. PMID:25172950

  20. Delivery of molecules to the lymph node via lymphatic vessels using ultrasound and nano/microbubbles.

    PubMed

    Kato, Shigeki; Shirai, Yuko; Kanzaki, Hiroyuki; Sakamoto, Maya; Mori, Shiro; Kodama, Tetsuya

    2015-05-01

    Lymph node (LN) dissection is the primary option for head and neck cancer when imaging modalities and biopsy confirm metastasis to the sentinel LN. However, there are no effective alternative treatments to dissection for LN metastasis. Here, we describe a novel drug delivery system combining nano/microbubbles (NMBs) with ultrasound (US) that exhibits considerable potential for the delivery of exogenous molecules into LNs through the lymphatic vessels. A solution containing fluorophores (as a model of a therapeutic molecule) and NMBs was injected into the subiliac LNs of MXH10/Mo-lpr/lpr mice, which develop systemic swelling of LNs (up to 13 mm in diameter, similar to human LNs). It was found that the NMBs were delivered to the entire area of the proper axillary LN (proper-ALN) via the lymphatic channels and that these were retained there for more than 8 min. Furthermore, exposure to US in the presence of NMBs enhanced the delivery of fluorophores into the lymphocytes near the lymphatic channels, compared with exposure to US in the absence of NMBs. It is proposed that a system using US and NMBs to deliver therapeutic drugs via lymphatic vessels can serve as a new treatment method for LN metastasis.

  1. Label-free 3D imaging of microstructure, blood, and lymphatic vessels within tissue beds in vivo.

    PubMed

    Zhi, Zhongwei; Jung, Yeongri; Wang, Ruikang K

    2012-03-01

    This Letter reports the use of an ultrahigh resolution optical microangiography (OMAG) system for simultaneous 3D imaging of microstructure and lymphatic and blood vessels without the use of an exogenous contrast agent. An automatic algorithm is developed to segment the lymphatic vessels from the microstructural images based on the fact that the lymph fluid is optically transparent. An OMAG system is developed that utilizes a broadband supercontinuum light source, providing an axial resolution of 2.3 μm and lateral resolution of 5.8 μm, capable of resolving the capillary vasculature and lymphatic vessels innervating microcirculatory tissue beds. Experimental demonstration is performed by showing detailed 3D lymphatic and blood vessel maps, coupled with morphology, within mouse ears in vivo.

  2. Label-free 3D imaging of microstructure, blood and lymphatic vessels within tissue beds in vivo

    PubMed Central

    Zhi, Zhongwei; Jung, Yeongri; Wang, Ruikang K.

    2014-01-01

    This letter reports the use of an ultrahigh resolution optical microangiography (OMAG) system for simultaneous 3D imaging of microstructure, lymphatic and blood vessels without the use of exogenous contrast agent. An automatic algorithm is developed to segment the lymphatic vessels from the microstructural images, based on the fact that the lymph fluid is optically transparent. The OMAG system is developed that utilizes a broadband supercontinuum light source, providing an axial resolution of 2.3 μm and lateral resolution of 5.8 μm, capable of resolving the capillary vasculature and lymphatic vessels innervating microcirculatory tissue beds. Experimental demonstration is performed by showing detailed 3D lymphatic and blood vessel maps, coupled with morphology, within mouse ears in vivo. PMID:22378402

  3. Surgical anatomy of the retroperitoneal spaces, Part III: Retroperitoneal blood vessels and lymphatics.

    PubMed

    Mirilas, Petros; Skandalakis, John E

    2010-02-01

    In this article, we discuss the surgical anatomy of the blood vessels and the lymphatic vessels and lymph nodes found in the retroperitoneum. Retroperitoneal blood vessels include the aorta and all its branches--parietal and visceral--from the diaphragm to the pelvis, and the inferior vena cava and its tributaries. The retroperitoneal lymphatics form a very rich and extensive chain. As a general rule, lymphatics follow the arteries and named lymph nodes are found at the root of the arteries. Retroperitoneal nodes of the abdomen comprise the inferior diaphragmatic nodes and the lumbar nodes. The latter are classified as left lumbar (aortic), intermediate (interaorticovenous), and right lumbar (caval). These nodes surround the aorta and the inferior vena cava. Around the aorta lie the paraortic nodes, preaortic nodes (include celiac, superior mesenteric, inferior mesenteric nodes collecting lymph from the splanchna supplied by the homonymous arteries), and retroaortic nodes. Similarly, around the vena cava lie the paracaval, precaval, and retrocaval nodes. Pelvic nodes include the common iliac, external and internal iliac, obturator, and sacral nodes.

  4. Finding an optimal method for imaging lymphatic vessels of the upper limb.

    PubMed

    O'Mahony, Susan; Rose, Sarah L; Chilvers, Alison J; Ballinger, James R; Solanki, Chandra K; Barber, Robert W; Mortimer, Peter S; Purushotham, Arnie D; Peters, A Michael

    2004-04-01

    Lymphoscintigraphy involves interstitial injection of radiolabelled particulate materials or radioproteins. Although several variations in the technique have been described, their place in clinical practice remains controversial. Traditional diagnostic criteria are based primarily on lymph node appearances but in situations such as breast cancer, where lymph nodes may have been excised, these criteria are of limited use. In these circumstances, lymphatic vessel morphology takes on greater importance as a clinical endpoint, so a method that gives good definition of lymphatic vessels would be useful. In patients with breast cancer, for example, such a method, used before and after lymph node resection, may assist in predicting the development of breast cancer-related lymphoedema. The aim of this study was to optimise a method for the visualisation of lymphatic vessels. Subcutaneous (sc) and intradermal (id) injection sites were compared, and technetium-99m nanocolloid, a particulate material, was compared with (99m)Tc-human immunoglobulin (HIG), which is a soluble macromolecule. Twelve normal volunteers were each studied on two occasions. In three subjects, id (99m)Tc-HIG was compared with sc (99m)Tc-HIG, in three id (99m)Tc-nanocolloid was compared with sc (99m)Tc-nanocolloid, in three id (99m)Tc-HIG was compared with id (99m)Tc-nanocolloid and in three sc (99m)Tc-HIG was compared with sc (99m)Tc-nanocolloid. Endpoints were quality of lymphatic vessel definition, the time after injection at which vessels were most clearly visualised, the rate constant of depot disappearance ( k) and the systemic blood accumulation rate as measured by gamma camera imaging over the liver or cardiac blood pool. Excellent definition of lymphatic vessels was obtained following id injection of either radiopharmaceutical, an injection route that was clearly superior to sc. Differences between radiopharmaceuticals were less clear, although after id injection, (99m)Tc-HIG gave images that

  5. Topographic study on nerve-associated lymphatic vessels in the murine craniofacial region by immunohistochemistry and electron microscopy.

    PubMed

    Furukawa, Masahide; Shimoda, Hiroshi; Kajiwara, Tooru; Kato, Seiji; Yanagisawa, Shigetaka

    2008-12-01

    The distribution and fine structure of lymphatic vessels associated with nerves was studied by immunohistochemistry in the murine craniofacial region. The tissue sections and blocks were immunostained for LYVE-1, protein gene product 9.5, CD34 and aquaporin-1 to demonstrate the lymphatic vessels, nerves, blood vessels and water channel protein, respectively. Transmission electron microscopic examination was also performed to investigate the relationship between the lymphatics and nerves. In the nasal area, the lymphatics were found in dura mater on the cribriform plate and beneath the nasal mucosa, this supposedly supplying the cerebrospinal fluid drainage route along the olfactory nerves. The proximal portions of the cranial nerves were equipped with the lymphatics in the epineurium. In the distal portions of the nerves, the lymphatics were distributed in close proximity of the perineural sheath, and thus might contribute to maintenance of microenvironment suitable for the nerves by an absorptive activity of the lymphatic endothelial cells. The present findings suggest that the lymphatic system associated with the cranial nerves provides the pathway for transport of cerebrospinal fluid, tissue fluid, and free cells involved in immune response and tumor metastasis in the craniofacial region.

  6. Permeability and contractile responses of collecting lymphatic vessels elicited by atrial and brain natriuretic peptides.

    PubMed

    Scallan, Joshua P; Davis, Michael J; Huxley, Virginia H

    2013-10-15

    Atrial and brain natriuretic peptides (ANP and BNP, respectively) are cardiac hormones released into the bloodstream in response to hypervolaemia or fluid shifts to the central circulation. The actions of both peptides include natriuresis and diuresis, a decrease in systemic blood pressure, and inhibition of the renin-angiotensin-aldosterone system. Further, ANP and BNP elicit increases in blood microvessel permeability sufficient to cause protein and fluid extravasation into the interstitium to reduce the vascular volume. Given the importance of the lymphatic vasculature in maintaining fluid balance, we tested the hypothesis that ANP or BNP (100 nM) would likewise elevate lymphatic permeability (Ps) to serum albumin. Using a microfluorometric technique adapted to in vivo lymphatic vessels, we determined that rat mesenteric collecting lymphatic Ps to rat serum albumin increased by 2.0 ± 0.4-fold (P = 0.01, n = 7) and 2.7 ± 0.8-fold (P = 0.07, n = 7) with ANP and BNP, respectively. In addition to measuring Ps responses, we observed changes in spontaneous contraction amplitude and frequency from the albumin flux tracings in vivo. Notably, ANP abolished spontaneous contraction amplitude (P = 0.005) and frequency (P = 0.006), while BNP augmented both parameters by ∼2-fold (P < 0.01 each). These effects of ANP and BNP on contractile function were examined further by using an in vitro assay. In aggregate, these data support the theory that an increase in collecting lymphatic permeability opposes the absorptive function of the lymphatic capillaries, and aids in the retention of protein and fluid in the interstitial space to counteract volume expansion.

  7. Use of a whole-slide imaging system to assess the presence and alteration of lymphatic vessels in joint sections of arthritic mice.

    PubMed

    Shi, J X; Liang, Q Q; Wang, Y J; Mooney, R A; Boyce, B F; Xing, L

    2013-11-01

    We investigated the presence and alteration of lymphatic vessels in joints of arthritic mice using a whole-slide imaging system. Joints and long bone sections were cut from paraffin blocks of two mouse models of arthritis: meniscal-ligamentous injury (MLI)-induced osteoarthritis (OA) and TNF transgene (TNF-Tg)-induced rheumatoid arthritis (RA). MLI-OA mice were fed a high fat diet to accelerate OA development. TNF-Tg mice were treated with lymphatic growth factor VEGF-C virus to stimulate lymphangiogenesis. Sections were double immunofluorescence stained with anti-podoplanin and alpha-smooth muscle actin antibodies. The area and number of lymphatic capillaries and mature lymphatic vessels were determined using a whole-slide imaging system and its associated software. Lymphatic vessels in joints were distributed in soft tissues mainly around the joint capsule, ligaments, fat pads and muscles. In long bones, enriched lymphatic vessels were present in the periosteal areas adjacent to the blood vessels. Occasionally, lymphatic vessels were observed in the cortical bone. Increased lymphatic capillaries, but decreased mature lymphatic vessels, were detected in both OA and RA joints. VEGF-C treatment increased lymphatic capillary and mature vessel formation in RA joints. Our findings suggest that the lymphatic system may play an important role in arthritis pathogenesis and treatment.

  8. The Schlemm's canal is a VEGF-C/VEGFR-3-responsive lymphatic-like vessel.

    PubMed

    Aspelund, Aleksanteri; Tammela, Tuomas; Antila, Salli; Nurmi, Harri; Leppänen, Veli-Matti; Zarkada, Georgia; Stanczuk, Lukas; Francois, Mathias; Mäkinen, Taija; Saharinen, Pipsa; Immonen, Ilkka; Alitalo, Kari

    2014-09-01

    In glaucoma, aqueous outflow into the Schlemm's canal (SC) is obstructed. Despite striking structural and functional similarities with the lymphatic vascular system, it is unknown whether the SC is a blood or lymphatic vessel. Here, we demonstrated the expression of lymphatic endothelial cell markers by the SC in murine and zebrafish models as well as in human eye tissue. The initial stages of SC development involved induction of the transcription factor PROX1 and the lymphangiogenic receptor tyrosine kinase VEGFR-3 in venous endothelial cells in postnatal mice. Using gene deletion and function-blocking antibodies in mice, we determined that the lymphangiogenic growth factor VEGF-C and its receptor, VEGFR-3, are essential for SC development. Delivery of VEGF-C into the adult eye resulted in sprouting, proliferation, and growth of SC endothelial cells, whereas VEGF-A obliterated the aqueous outflow system. Furthermore, a single injection of recombinant VEGF-C induced SC growth and was associated with trend toward a sustained decrease in intraocular pressure in adult mice. These results reveal the evolutionary conservation of the lymphatic-like phenotype of the SC, implicate VEGF-C and VEGFR-3 as critical regulators of SC lymphangiogenesis, and provide a basis for further studies on therapeutic manipulation of the SC with VEGF-C in glaucoma treatment.

  9. Effects of Bothrops asper Snake Venom on Lymphatic Vessels: Insights into a Hidden Aspect of Envenomation

    PubMed Central

    Mora, Javier; Mora, Rodrigo; Lomonte, Bruno; Gutiérrez, José María

    2008-01-01

    Background Envenomations by the snake Bothrops asper represent a serious medical problem in Central America and parts of South America. These envenomations concur with drastic local tissue pathology, including a prominent edema. Since lymph flow plays a role in the maintenance of tissue fluid balance, the effect of B. asper venom on collecting lymphatic vessels was studied. Methodology/Principal Findings B. asper venom was applied to mouse mesentery, and the effects were studied using an intravital microscopy methodology coupled with an image analysis program. B. asper venom induced a dose-dependent contraction of collecting lymphatic vessels, resulting in a reduction of their lumen and in a halting of lymph flow. The effect was reproduced by a myotoxic phospholipase A2 (PLA2) homologue isolated from this venom, but not by a hemorrhagic metalloproteinase or a coagulant thrombin-like serine proteinase. In agreement with this, treatment of the venom with fucoidan, a myotoxin inhibitor, abrogated the effect, whereas no inhibition was observed after incubation with the peptidomimetic metalloproteinase inhibitor Batimastat. Moreover, fucoidan significantly reduced venom-induced footpad edema. The myotoxic PLA2 homologue, known to induce skeletal muscle necrosis, was able to induce cytotoxicity in smooth muscle cells in culture and to promote an increment in the permeability to propidium iodide in these cells. Conclusions/Significance Our observations indicate that B. asper venom affects collecting lymphatic vessels through the action of myotoxic PLA2s on the smooth muscle of these vessels, inducing cell contraction and irreversible cell damage. This activity may play an important role in the pathogenesis of the pronounced local edema characteristic of viperid snakebite envenomation, as well as in the systemic biodistribution of the venom, thus representing a potential therapeutical target in these envenomations. PMID:18923712

  10. Mast cells in common wolffish Anarhichas lupus L.: ontogeny, distribution and association with lymphatic vessels.

    PubMed

    Hellberg, Hege; Bjerkås, Inge; Vågnes, Øyvind B; Noga, Edward J

    2013-12-01

    The morphology, ontogeny and tissue distribution of mast cells were studied in common wolffish(Anarhichas lupus L.) at the larval, juvenile and adult life stages using light and electron-microscopy and immunohistochemistry. Fish were sampled at 1 day, 1, 2, 3, 4, 8 and 12 weeks post-hatching in addition to 6 and 9 months and 2 years and older. From 8 weeks post-hatching, mast cells in common wolffish mainly appeared as oval or rounded cells 8-15 mm in diameter with an eccentrically placed, ovoid nucleus and filled with cytoplasmic granules up to 1.2 mm in diameter. Granules were refractile and eosinophilic to slightly basophilic in H&E and stained bright red with Martius-scarlet-blue and purple with pinacyanol erythrosinate in formalin-fixed tissues. Mast cells stained positive for piscidin 4 and Fc ε RI by immunohistochemistry. From 1 day to 4 weeks post-hatching, immature mast cell containing only a few irregularly sized cytoplasmic granules were observed by light and electron-microscopy in loose connective tissue of cranial areas. From 1 day post-hatching, these cells stained positive for piscidin 4 and Fc ε RI by immunohistochemistry. From 12 weeks post-hatching, mast cells showed a primarily perivascular distribution and were particularly closely associated with lymphatic vessels and sinuses. Mast cells were mainly located at the peripheral border of the adventitia of arteries and veins, while they were in intimate contact with the endothelium of the lymphatic vessels. Numerous mast cells were observed in the intestine. A stratum compactum, as described in salmonids, was not observed in wolffish intestine,nor were mast cells confined to a separate layer, a stratum granulosum. Lymphatic vessels consisting of endothelium, intimal connective tissue and a poorly developed basal lamina were observed in the intestine. Scanning electron microscopy was used to compare the structure and localization of intestinal mast cells of common wolffish and rainbow trout

  11. Characterization of internodal collecting lymphatic vessel function after surgical removal of an axillary lymph node in mice.

    PubMed

    Kwon, Sunkuk; Price, Roger E

    2016-04-01

    Secondary lymphedema is an acquired lymphatic disorder, which occurs because of damage to the lymphatic system from surgery and/or radiation therapy for cancer treatment. However, it remains unknown how post-nodal collecting lymphatic vessels (CLVs) draining to the surgical wound area change in response to lymphadenectomy. We investigated functional and architectural changes of inguinal-to-axillary internodal CLVs (ICLVs) in mice after a single axillary LN (ALN) dissection using near-infrared fluorescence imaging. Our data showed no lymph flow in the ICLVs draining from the inguinal LN (ILN) at 2 days post-surgery. External compression enabled visualization of a small segment of contractile fluorescent ICLVs, but not all the way to the axillary region. At day 6, abnormal lymphatic drainage patterns, including lateral and retrograde lymph flow via vessels branching off the ICLVs were observed, which started to disappear beginning 9 days after surgery. The administration of vascular endothelial growth factor (VEGF)-C into the wound increased resolution of altered lymphatic drainage. Lymphatic drainage from the base of the tail to the ILN did not significantly change over time. These results demonstrate that lymph flow in the CLVs is dramatically affected by a LN dissection and long-term interruption of lymph flow might cause CLV dysfunction and thus contribute to chronic lymphatic disorders. PMID:27446639

  12. Preclinical lymphatic imaging.

    PubMed

    Zhang, Fan; Niu, Gang; Lu, Guangming; Chen, Xiaoyuan

    2011-08-01

    Noninvasive in vivo imaging of lymphatic vessels and lymphatic nodes is expected to fulfill the purpose of analyzing lymphatic vessels and their function, understanding molecular mechanisms of lymphangiogenesis and lymphatic spread of tumors, and utilizing lymphatic molecular markers as a prognostic or diagnostic indicator. In this review, we provide a comprehensive summary of in vivo imaging modalities for detecting lymphatic vessels, lymphatic drainage, and lymphatic nodes, which include conventional lymphatic imaging techniques such as dyes and radionuclide scintigraphy as well as novel techniques for lymphatic imaging such as optical imaging, computed tomography, magnetic resonance imaging, ultrasound, positron emission tomography using lymphatic biomarkers, photoacoustic imaging, and combinations of multiple modalities. The field of lymphatic imaging is ever evolving, and technological advances, combined with the development of new contrast agents, continue to improve the research of lymphatic vascular system in health and disease states as well as to improve the accuracy of diagnosis in the relevant diseases.

  13. Preclinical Lymphatic Imaging

    PubMed Central

    Zhang, Fan; Niu, Gang; Lu, Guangming; Chen, Xiaoyuan

    2011-01-01

    Non-invasive in vivo imaging of lymphatic vessels and lymphatic nodes is expected to fulfill the purpose of analyzing lymphatic vessels and their function, understanding molecular mechanisms of lymphangiogenesis and lymphatic spread of tumors, and utilizing lymphatic molecular markers as a prognostic or diagnostic indicator. In this review, we provide a comprehensive summary of in vivo imaging modalities for detecting lymphatic vessels, lymphatic drainage, lymphatic nodes, which include conventional lymphatic imaging techniques such as dyes and radionuclide scintigraphy as well as novel techniques for lymphatic imaging such as optical imaging, computed tomography (CT), magnetic resonance imaging (MRI), ultrasound, positron emission tomography (PET) using lymphatic biomarkers, photoacoustic imaging and combinations of multiple modalities. The field of lymphatic imaging is ever evolving, and technological advances, combined with the development of new contrast agents, continue to improve the research of lymphatic vascular system in health and disease states as well as to improve the accuracy of diagnosis in the relevant diseases. PMID:20862613

  14. Mechanisms of Acute Alcohol Intoxication-Induced Modulation of Cyclic Mobilization of [Ca2+] in Rat Mesenteric Lymphatic Vessels

    PubMed Central

    Kerut, Edmund K.; Breslin, Jerome W.; Molina, Patricia E.

    2015-01-01

    Abstract Background: We have demonstrated that acute alcohol intoxication (AAI) increases the magnitude of Ca2+ transients in pumping lymphatic vessels. We tested the contribution of extracellular Ca2+ via L-type Ca2+ channels and intracellular Ca2+ release from the sarcoplasmic reticulum (SR) to the AAI-induced increase in Ca2+ transients. Methods and Results: AAI was produced by intragastric administration of 30% alcohol to conscious, unrestrained rats; isovolumic administration of water served as the control. Mesenteric lymphatic vessels were isolated, cannulated, and loaded with Fura-2 AM to measure changes in intracellular Ca2+. Measurements were made at intraluminal pressures of 2, 6, and 10 cm H2O. L-type Ca2+ channels were blocked with nifedipine; IP-3 receptors were inhibited with xestospongin C; and SR Ca2+ release and Ca2+ pool (Ca2+ free APSS) were achieved using caffeine. Nifedipine reduced lymphatic Ca2+ transient magnitude in both AAI and control groups at all pressures tested, but reduced lymphatic contraction frequency only in the control group. Xestospongin C did not significantly change any of the Ca2+ parameters in either group; however, fractional shortening increased in the controls at low transmural pressure. RyR (ryanodine receptor) activation with caffeine resulted in a single contraction with a greater Ca2+ transient in lymphatics from AAI than those from controls. SR Ca2+ pool was also greater in lymphatics isolated from AAI- than from control animals. Conclusions: These data suggest that 1) L-type Ca2+ channels contribute to the AAI-induced increase in lymphatic Ca2+ transient, 2) blockage of IP-3 receptors could increase calcium sensitivity, and 3) AAI increases Ca2+ storage in the SR in lymphatic vessels. PMID:26056854

  15. Lymphatic system: an active pathway for immune protection.

    PubMed

    Liao, Shan; von der Weid, P Y

    2015-02-01

    Lymphatic vessels are well known to participate in the immune response by providing the structural and functional support for the delivery of antigens and antigen presenting cells to draining lymph nodes. Recent advances have improved our understanding of how the lymphatic system works and how it participates to the development of immune responses. New findings suggest that the lymphatic system may control the ultimate immune response through a number of ways which may include guiding antigen/dendritic cells (DC) entry into initial lymphatics at the periphery; promoting antigen/DC trafficking through afferent lymphatic vessels by actively facilitating lymph and cell movement; enabling antigen presentation in lymph nodes via a network of lymphatic endothelial cells and lymph node stroma cell and finally by direct lymphocytes exit from lymph nodes. The same mechanisms are likely also important to maintain peripheral tolerance. In this review we will discuss how the morphology and gene expression profile of the lymphatic endothelial cells in lymphatic vessels and lymph nodes provides a highly efficient pathway to initiate immune responses. The fundamental understanding of how lymphatic system participates in immune regulation will guide the research on lymphatic function in various diseases.

  16. Ex-Vivo Lymphatic Perfusion System for Independently Controlling Pressure Gradient and Transmural Pressure in Isolated Vessels

    PubMed Central

    Kornuta, Jeffrey A.; Dixon, J. Brandon

    2015-01-01

    In addition to external forces, collecting lymphatic vessels intrinsically contract to transport lymph from the extremities to the venous circulation. As a result, the lymphatic endothelium is routinely exposed to a wide range of dynamic mechanical forces, primarily fluid shear stress and circumferential stress, which have both been shown to affect lymphatic pumping activity. Although various ex-vivo perfusion systems exist to study this innate pumping activity in response to mechanical stimuli, none are capable of independently controlling the two primary mechanical forces affecting lymphatic contractility: transaxial pressure gradient, ΔP, which governs fluid shear stress; and average transmural pressure, Pavg, which governs circumferential stress. Hence, the authors describe a novel ex-vivo lymphatic perfusion system (ELPS) capable of independently controlling these two outputs using a linear, explicit model predictive control (MPC) algorithm. The ELPS is capable of reproducing arbitrary waveforms within the frequency range observed in the lymphatics in vivo, including a time-varying ΔP with a constant Pavg, time-varying ΔP and Pavg, and a constant ΔP with a time-varying Pavg. In addition, due to its implementation of syringes to actuate the working fluid, a post-hoc method of estimating both the flow rate through the vessel and fluid wall shear stress over multiple, long (5 sec) time windows is also described. PMID:24809724

  17. Direct transcriptional regulation of neuropilin-2 by COUP-TFII modulates multiple steps in murine lymphatic vessel development

    PubMed Central

    Lin, Fu-Jung; Chen, Xinpu; Qin, Jun; Hong, Young-Kwon; Tsai, Ming-Jer; Tsai, Sophia Y.

    2010-01-01

    The lymphatic system plays a key role in tissue fluid homeostasis. Lymphatic dysfunction contributes to the pathogenesis of many human diseases, including lymphedema and tumor metastasis. However, the mechanisms regulating lymphangiogenesis remain largely unknown. Here, we show that COUP-TFII (also known as Nr2f2), an orphan member of the nuclear receptor superfamily, mediates both developmental and pathological lymphangiogenesis in mice. Conditional ablation of COUP-TFII at an early embryonic stage resulted in failed formation of pre-lymphatic ECs (pre-LECs) and lymphatic vessels. COUP-TFII deficiency at a late developmental stage resulted in loss of LEC identity, gain of blood EC fate, and impaired lymphatic vessel sprouting. siRNA-mediated downregulation of COUP-TFII in cultured primary human LECs demonstrated that the maintenance of lymphatic identity and VEGF-C–induced lymphangiogenic activity, including cell proliferation and migration, are COUP-TFII–dependent and cell-autonomous processes. COUP-TFII enhanced the pro-lymphangiogenic actions of VEGF-C, at least in part by directly stimulating expression of neuropilin-2, a coreceptor for VEGF-C. In addition, COUP-TFII inactivation in a mammary gland mouse tumor model resulted in inhibition of tumor lymphangiogenesis, suggesting that COUP-TFII also regulates neo-lymphangiogenesis in the adult. Thus, COUP-TFII is a critical factor that controls lymphangiogenesis in embryonic development and tumorigenesis in adults. PMID:20364082

  18. Distinct roles of L- and T-type voltage-dependent Ca2+ channels in regulation of lymphatic vessel contractile activity.

    PubMed

    Lee, Stewart; Roizes, Simon; von der Weid, Pierre-Yves

    2014-12-15

    Lymph drainage maintains tissue fluid homeostasis and facilitates immune response. It is promoted by phasic contractions of collecting lymphatic vessels through which lymph is propelled back into the blood circulation. This rhythmic contractile activity (i.e. lymphatic pumping) increases in rate with increase in luminal pressure and relies on activation of nifedipine-sensitive voltage-dependent Ca(2+) channels (VDCCs). Despite their importance, these channels have not been characterized in lymphatic vessels. We used pressure- and wire-myography as well as intracellular microelectrode electrophysiology to characterize the pharmacological and electrophysiological properties of L-type and T-type VDCCs in rat mesenteric lymphatic vessels and evaluated their particular role in the regulation of lymphatic pumping by stretch. We complemented our study with PCR and confocal immunofluorescence imaging to investigate the expression and localization of these channels in lymphatic vessels. Our data suggest a delineating role of VDCCs in stretch-induced lymphatic vessel contractions, as the stretch-induced increase in force of lymphatic vessel contractions was significantly attenuated in the presence of L-type VDCC blockers nifedipine and diltiazem, while the stretch-induced increase in contraction frequency was significantly decreased by the T-type VDCC blockers mibefradil and nickel. The latter effect was correlated with a hyperpolarization. We propose that activation of T-type VDCCs depolarizes membrane potential, regulating the frequency of lymphatic contractions via opening of L-type VDCCs, which drive the strength of contractions.

  19. Absence of Lymphatic Vessels in PCNSL May Contribute to Confinement of Tumor Cells to the Central Nervous System.

    PubMed

    Deckert, Martina; Brunn, Anna; Montesinos-Rongen, Manuel; Siebert, Reiner

    2016-06-01

    Primary central nervous system (CNS) lymphoma (PCNSL) is a mature lymphoma of the diffuse large B-cell lymphoma (DLBCL) type confined to the CNS. Despite cytomorphological similarities between PCNSL and systemic DLBCL, molecular differences between both entities have been identified. The exclusively topographical restriction of PCNSL to the CNS is an unexplained mystery. To address the question of whether the unique lymphatic drainage system of the CNS, which differs from that of other organs, may play a role for this peculiar behavior, we investigated a series of 20 PCNSLs for the presence of lymphatic vessels by immunohistochemistry for Lyve-1, podoplanin, and Prox-1 expression. All PCNSLs lacked lymphatic vessels and, in this regard, were similar to 20 glioblastoma multiforme samples. In contrast to these tumors, all of which were located in the deep brain parenchyma, dural and meningeal DLBCL harbored lymphatic vessels that expressed Lyve-1 (3/8 tumors), podoplanin (5/8 tumors), and Prox-1 (5/8 tumors) in areas where the tumors had invaded the fibrous tissue of the dura. These data indicate that local topographical characteristics of the specific lymphatic drainage system may contribute to confinement of the tumor cells in PCNSL and malignant gliomas.

  20. Absence of Lymphatic Vessels in PCNSL May Contribute to Confinement of Tumor Cells to the Central Nervous System.

    PubMed

    Deckert, Martina; Brunn, Anna; Montesinos-Rongen, Manuel; Siebert, Reiner

    2016-06-01

    Primary central nervous system (CNS) lymphoma (PCNSL) is a mature lymphoma of the diffuse large B-cell lymphoma (DLBCL) type confined to the CNS. Despite cytomorphological similarities between PCNSL and systemic DLBCL, molecular differences between both entities have been identified. The exclusively topographical restriction of PCNSL to the CNS is an unexplained mystery. To address the question of whether the unique lymphatic drainage system of the CNS, which differs from that of other organs, may play a role for this peculiar behavior, we investigated a series of 20 PCNSLs for the presence of lymphatic vessels by immunohistochemistry for Lyve-1, podoplanin, and Prox-1 expression. All PCNSLs lacked lymphatic vessels and, in this regard, were similar to 20 glioblastoma multiforme samples. In contrast to these tumors, all of which were located in the deep brain parenchyma, dural and meningeal DLBCL harbored lymphatic vessels that expressed Lyve-1 (3/8 tumors), podoplanin (5/8 tumors), and Prox-1 (5/8 tumors) in areas where the tumors had invaded the fibrous tissue of the dura. These data indicate that local topographical characteristics of the specific lymphatic drainage system may contribute to confinement of the tumor cells in PCNSL and malignant gliomas. PMID:27142645

  1. Incorporating measured valve properties into a numerical model of a lymphatic vessel

    PubMed Central

    Macaskill, C.; Moore, J.E.

    2015-01-01

    An existing lumped-parameter model of multiple lymphangions (lymphatic vascular segments) in series is adapted for the incorporation of recent physiological measurements of lymphatic vascular properties. The new data show very marked nonlinearity of the passive pressure-diameter relation during distension, relative to comparable blood vessels, and complex valve behaviour. Since lymph is transported as a result of either the active contraction or the passive squeezing of vascular segments situated between two one-way valves, the performance of these valves is of primary importance. The valves display hysteresis (the opening and closing pressure-drop thresholds differ), a bias to staying open (both state changes occur when the trans-valve pressure drop is adverse), and pressure-drop threshold dependence on transmural pressure. These properties, in combination with the strong nonlinearity that valve operation represents, have in turn caused intriguing numerical problems in the model, and we describe numerical stratagems by which we have overcome the problems. The principal problem is also generalised into a relatively simple mathematical example, for which solution detail is provided using two different solvers. PMID:23387996

  2. Microparticle image velocimetry approach to flow measurements in isolated contracting lymphatic vessels

    NASA Astrophysics Data System (ADS)

    Margaris, Konstantinos N.; Nepiyushchikh, Zhanna; Zawieja, David C.; Moore, James; Black, Richard A.

    2016-02-01

    We describe the development of an optical flow visualization method for resolving the flow velocity vector field in lymphatic vessels in vitro. The aim is to develop an experimental protocol for accurately estimating flow parameters, such as flow rate and shear stresses, with high spatial and temporal resolution. Previous studies in situ have relied on lymphocytes as tracers, but their low density resulted in a reduced spatial resolution whereas the assumption that the flow was fully developed in order to determine the flow parameters of interest may not be valid, especially in the vicinity of the valves, where the flow is undoubtedly more complex. To overcome these issues, we have applied the time-resolved microparticle image velocimetry (μ-PIV) technique, a well-established method that can provide increased spatial and temporal resolution that this transient flow demands. To that end, we have developed a custom light source, utilizing high-power light-emitting diodes, and associated control and image processing software. This paper reports the performance of the system and the results of a series of preliminary experiments performed on vessels isolated from rat mesenteries, demonstrating, for the first time, the successful application of the μ-PIV technique in these vessels.

  3. Microparticle image velocimetry approach to flow measurements in isolated contracting lymphatic vessels.

    PubMed

    Margaris, Konstantinos N; Nepiyushchikh, Zhanna; Zawieja, David C; Moore, James; Black, Richard A

    2016-02-01

    We describe the development of an optical flow visualization method for resolving the flow velocity vector field in lymphatic vessels in vitro. The aim is to develop an experimental protocol for accurately estimating flow parameters, such as flow rate and shear stresses, with high spatial and temporal resolution. Previous studies in situ have relied on lymphocytes as tracers, but their low density resulted in a reduced spatial resolution whereas the assumption that the flow was fully developed in order to determine the flow parameters of interest may not be valid, especially in the vicinity of the valves, where the flow is undoubtedly more complex. To overcome these issues, we have applied the time-resolved microparticle image velocimetry (μ -PIV) technique, a well-established method that can provide increased spatial and temporal resolution that this transient flow demands. To that end, we have developed a custom light source, utilizing high-power light-emitting diodes, and associated control and image processing software. This paper reports the performance of the system and the results of a series of preliminary experiments performed on vessels isolated from rat mesenteries, demonstrating, for the first time, the successful application of the μ -PIV technique in these vessels.

  4. Local inhibition of elastase reduces EMILIN1 cleavage reactivating lymphatic vessel function in a mouse lymphoedema model

    PubMed Central

    Pivetta, Eliana; Wassermann, Bruna; Belluz, Lisa Del Bel; Danussi, Carla; Modica, Teresa Maria Elisa; Maiorani, Orlando; Bosisio, Giulia; Boccardo, Francesco; Canzonieri, Vincenzo; Colombatti, Alfonso

    2016-01-01

    Lymphatic vasculature critically depends on the connections of lymphatic endothelial cells with the extracellular matrix (ECM), which are mediated by anchoring filaments (AFs). The ECM protein EMILIN1 is a component of AFs and is involved in the regulation of lymphatic vessel functions: accordingly, Emilin1−/− mice display lymphatic vascular morphological alterations, leading to functional defects such as mild lymphoedema, lymph leakage and compromised lymph drainage. In the present study, using a mouse post-surgical tail lymphoedema model, we show that the acute phase of acquired lymphoedema correlates with EMILIN1 degradation due to neutrophil elastase (NE) released by infiltrating neutrophils. As a consequence, the intercellular junctions of lymphatic endothelial cells are weakened and drainage to regional lymph nodes is severely affected. The local administration of sivelestat, a specific NE inhibitor, prevents EMILIN1 degradation and reduces lymphoedema, restoring a normal lymphatic functionality. The finding that, in human secondary lymphoedema samples, we also detected cleaved EMILIN1 with the typical bands of an NE-dependent pattern of fragmentation establishes a rationale for a powerful strategy that targets NE inhibition. In conclusion, the attempts to block EMILIN1 degradation locally represent the basis for a novel ‘ECM’ pharmacological approach to assessing new lymphoedema treatments. PMID:26920215

  5. [Direct and prolonged effect of thyroliberin in ultra small doses on contractility of the white rat mesentery lymphatic vessels].

    PubMed

    Sanzhieva, L Ts; Lelekova, T V; Ashmarin, I P

    2003-01-01

    The prolonged effect of thyroliberin in ULD after single intramuscular injection on contractility of lymphatic vessels directly was investigated. The controlled group of animals received injection of 0.2 ml of physiological solution. The experimental group was injected by 0.2 ml of thyroliberin in concentrations of 10(-10) or 10(-16) mol/l (1 x 10(-4) and 1 x 10(-10) micrograms/kg of the body weight respectively). During the experiment the animals were grouped in the following way: 1) directly after the injection; 2) 3 hours later; 3) on the 1st day and then every day during 2 weeks. Lymphatic vessels reactivity of the experimental animals as well as controlled was studied by application of thyroliberin and noradrenalin (in concentrations of 1 x 10(-16) and 1 x 10(-6) mol/l respectively) directly on mesentery lymphatic vessels. The lymphatic vessels reaction in control group of animals on the noradrenalin and thyroliberin was the same during the period of observation. Thyroliberin stimulated contractility at concentration of 1 x 10(-16) mol/l. The reaction of experimental group was dramatically decreased to 10(-4) mol/l on the 1st and the 3rd day (in the case i.m. injected concentration 1 x 10(-10) mol/l) and to 10(-10) mol/l (in the case of i.m. injected concentration 10(-16) mol/l). The lymphatic vessels reactivity to exogenous thyroliberin gradually established at the 6-7th days till 12th day from the moment of thyroliberin injection. The mechanisms of the action of thyroliberin in ULD are discussed.

  6. Enzyme-histochemical study on postnatal development of rat stomach lymphatic vessels.

    PubMed

    Ji, R C; Kato, S

    1997-07-01

    Postnatal development of rat gastric lymphatics was studied by an enzyme-histochemical method to elucidate the morphological changes of lymphatics and their relationship to maturation and function, especially in the glandular portion. The significant features of 5'-Nase-positive lymphatics in distribution and structure were examined in different stages (within 24 hr, 4-21 days, and 2 months). Lymphatics in the greater curvature and anterior wall grew much slower than those in the lesser curvature and posterior wall of the stomach in newborn and infant rats. Lymphatic islands isolated from the primary lymphatic networks in the submucosa and subserosa underwent a morphological change during this early period. This is considered one of the basic steps in lymphatic development. Occurrence of lymphatic networks in the deep lamina propria indicates that development in the gastric wall is well characterized from Day 10. With further growth and modification of lymphatics, the networks in the different layers formed an extensive communication network and many lymphatic valves were found in the submucosa and subserosa. Pinocytotic vesicles, open junctions, and intraendothelial channels were frequently detected in the mucosal and submucosal lymphatic networks of the corpus-antrum and antrum-duodenum divisional zones in the adult rats. These findings suggest that developing lymphatics in the rat stomach may represent rapidly growing tissue not only with high 5'-Nase activity but also with high adaptability for future physiological demands.

  7. NOK/STYK1 promotes the genesis and remodeling of blood and lymphatic vessels during tumor progression.

    PubMed

    Liu, Yue; Li, Tianqi; Hu, Dan; Zhang, Shuping

    2016-09-01

    Previous studies have indicated that the overexpression of NOK, also named STYK1, led to tumorigenesis and metastasis. Here, we provide evidence that increased expression of NOK/STYK1 caused marked alterations in the overall and inner structures of tumors and substantially facilitates the genesis and remodeling of the blood and lymphatic vessels during tumor progression. In particular, NOK-expressed HeLa stable cells (HeLa-K) significantly enhanced tumor growth and metastasis in xenografted nude mice. Hematoxylin and eosin (HE) staining demonstrated that the tumor tissues generated by HeLa-K cells were much more ichorous and had more interspaces than those generated by control HeLa cells (HeLa-C). The fluorescent areas stained with cluster of differentiation 31 (CD31), a marker protein for blood vessels, appeared to be in different patterns. The total blood vessels, especially the ring patterns, within the tumors of the HeLa-K group were highly enriched compared with those in the HeLa-C group. NOK-HA was demonstrated to be well colocalized with CD31 in the wall of the tubular structures within tumor tissues. Interestingly, antibody staining of the lymphatic vessel endothelial hyaluronan receptor (LYVE-1) further revealed the increase in ring (oratretic strip-like) lymphatic vessels in either the peritumoral or intratumoral areas in the HeLa-K group compared with the HeLa-C group. Consistently, the analysis of human cancerous tissue also showed that NOK was highly expressed in the walls of tubular structures. Thus, our results reveal a novel tumorigenic function of NOK to mediate the genesis and remodeling of blood and lymphatic vessels during tumor progression.

  8. Anatomy of the lymphatics.

    PubMed

    Skandalakis, John E; Skandalakis, Lee J; Skandalakis, Panagiotis N

    2007-01-01

    The lymphatic system is perhaps the most complicated system of Homo sapiens. An introduction to the anatomy, embryology, and anomalies of the lymphatics is presented. The overall anatomy and drainage of the lymphatic vessels in outlined. The topographic anatomy, relations, and variations of the principle vessels of the lymphatic system (the right lymphatic duct, the thoracic duct, and the cisterna chyli) are presented in detail.

  9. The dual role of tumor lymphatic vessels in dissemination of metastases and immune response development.

    PubMed

    Stachura, Joanna; Wachowska, Malgorzata; Kilarski, Witold W; Güç, Esra; Golab, Jakub; Muchowicz, Angelika

    2016-07-01

    Lymphatic vasculature plays a crucial role in the immune response, enabling transport of dendritic cells (DCs) and antigens (Ags) into the lymph nodes. Unfortunately, the lymphatic system has also a negative role in the progression of cancer diseases, by facilitating the metastatic spread of many carcinomas to the draining lymph nodes. The lymphatics can promote antitumor immune response as well as tumor tolerance. Here, we review the role of lymphatic endothelial cells (LECs) in tumor progression and immunity and mechanism of action in the newest anti-lymphatic therapies, including photodynamic therapy (PDT).

  10. The dual role of tumor lymphatic vessels in dissemination of metastases and immune response development

    PubMed Central

    Stachura, Joanna; Wachowska, Malgorzata; Kilarski, Witold W.; Güç, Esra; Golab, Jakub; Muchowicz, Angelika

    2016-01-01

    ABSTRACT Lymphatic vasculature plays a crucial role in the immune response, enabling transport of dendritic cells (DCs) and antigens (Ags) into the lymph nodes. Unfortunately, the lymphatic system has also a negative role in the progression of cancer diseases, by facilitating the metastatic spread of many carcinomas to the draining lymph nodes. The lymphatics can promote antitumor immune response as well as tumor tolerance. Here, we review the role of lymphatic endothelial cells (LECs) in tumor progression and immunity and mechanism of action in the newest anti-lymphatic therapies, including photodynamic therapy (PDT).

  11. The dual role of tumor lymphatic vessels in dissemination of metastases and immune response development

    PubMed Central

    Stachura, Joanna; Wachowska, Malgorzata; Kilarski, Witold W.; Güç, Esra; Golab, Jakub; Muchowicz, Angelika

    2016-01-01

    ABSTRACT Lymphatic vasculature plays a crucial role in the immune response, enabling transport of dendritic cells (DCs) and antigens (Ags) into the lymph nodes. Unfortunately, the lymphatic system has also a negative role in the progression of cancer diseases, by facilitating the metastatic spread of many carcinomas to the draining lymph nodes. The lymphatics can promote antitumor immune response as well as tumor tolerance. Here, we review the role of lymphatic endothelial cells (LECs) in tumor progression and immunity and mechanism of action in the newest anti-lymphatic therapies, including photodynamic therapy (PDT). PMID:27622039

  12. The dual role of tumor lymphatic vessels in dissemination of metastases and immune response development.

    PubMed

    Stachura, Joanna; Wachowska, Malgorzata; Kilarski, Witold W; Güç, Esra; Golab, Jakub; Muchowicz, Angelika

    2016-07-01

    Lymphatic vasculature plays a crucial role in the immune response, enabling transport of dendritic cells (DCs) and antigens (Ags) into the lymph nodes. Unfortunately, the lymphatic system has also a negative role in the progression of cancer diseases, by facilitating the metastatic spread of many carcinomas to the draining lymph nodes. The lymphatics can promote antitumor immune response as well as tumor tolerance. Here, we review the role of lymphatic endothelial cells (LECs) in tumor progression and immunity and mechanism of action in the newest anti-lymphatic therapies, including photodynamic therapy (PDT). PMID:27622039

  13. Label-free optical lymphangiography: development of an automatic segmentation method applied to optical coherence tomography to visualize lymphatic vessels using Hessian filters.

    PubMed

    Yousefi, Siavash; Qin, Jia; Zhi, Zhongwei; Wang, Ruikang K

    2013-08-01

    Lymphatic vessels are a part of the circulatory system that collect plasma and other substances that have leaked from the capillaries into interstitial fluid (lymph) and transport lymph back to the circulatory system. Since lymph is transparent, lymphatic vessels appear as dark hallow vessel-like regions in optical coherence tomography (OCT) cross sectional images. We propose an automatic method to segment lymphatic vessel lumen from OCT structural cross sections using eigenvalues of Hessian filters. Compared to the existing method based on intensity threshold, Hessian filters are more selective on vessel shape and less sensitive to intensity variations and noise. Using this segmentation technique along with optical micro-angiography allows label-free noninvasive simultaneous visualization of blood and lymphatic vessels in vivo. Lymphatic vessels play an important role in cancer, immune system response, inflammatory disease, wound healing and tissue regeneration. Development of imaging techniques and visualization tools for lymphatic vessels is valuable in understanding the mechanisms and studying therapeutic methods in related disease and tissue response.

  14. Label-free optical lymphangiography: development of an automatic segmentation method applied to optical coherence tomography to visualize lymphatic vessels using Hessian filters

    NASA Astrophysics Data System (ADS)

    Yousefi, Siavash; Qin, Jia; Zhi, Zhongwei; Wang, Ruikang K.

    2013-08-01

    Lymphatic vessels are a part of the circulatory system that collect plasma and other substances that have leaked from the capillaries into interstitial fluid (lymph) and transport lymph back to the circulatory system. Since lymph is transparent, lymphatic vessels appear as dark hallow vessel-like regions in optical coherence tomography (OCT) cross sectional images. We propose an automatic method to segment lymphatic vessel lumen from OCT structural cross sections using eigenvalues of Hessian filters. Compared to the existing method based on intensity threshold, Hessian filters are more selective on vessel shape and less sensitive to intensity variations and noise. Using this segmentation technique along with optical micro-angiography allows label-free noninvasive simultaneous visualization of blood and lymphatic vessels in vivo. Lymphatic vessels play an important role in cancer, immune system response, inflammatory disease, wound healing and tissue regeneration. Development of imaging techniques and visualization tools for lymphatic vessels is valuable in understanding the mechanisms and studying therapeutic methods in related disease and tissue response.

  15. Label-free optical lymphangiography: development of an automatic segmentation method applied to optical coherence tomography to visualize lymphatic vessels using Hessian filters.

    PubMed

    Yousefi, Siavash; Qin, Jia; Zhi, Zhongwei; Wang, Ruikang K

    2013-08-01

    Lymphatic vessels are a part of the circulatory system that collect plasma and other substances that have leaked from the capillaries into interstitial fluid (lymph) and transport lymph back to the circulatory system. Since lymph is transparent, lymphatic vessels appear as dark hallow vessel-like regions in optical coherence tomography (OCT) cross sectional images. We propose an automatic method to segment lymphatic vessel lumen from OCT structural cross sections using eigenvalues of Hessian filters. Compared to the existing method based on intensity threshold, Hessian filters are more selective on vessel shape and less sensitive to intensity variations and noise. Using this segmentation technique along with optical micro-angiography allows label-free noninvasive simultaneous visualization of blood and lymphatic vessels in vivo. Lymphatic vessels play an important role in cancer, immune system response, inflammatory disease, wound healing and tissue regeneration. Development of imaging techniques and visualization tools for lymphatic vessels is valuable in understanding the mechanisms and studying therapeutic methods in related disease and tissue response. PMID:23922124

  16. The immunohistochemical analysis of the proliferative activity and the maturity degree of lymphatic vessels in oral squamous cell carcinomas.

    PubMed

    Ciurea, Raluca Niculina; Stepan, Alex Emilian; Simionescu, Cristiana Eugenia; Mărgăritescu, Claudiu; Pirici, Daniel; Tica, Oana Sorina; Ciurea, Marius Eugen; Stepan, Desdemona; Enache, Oana Andreea; Vîlcea, Alina Maria; Stoica, Loredana Elena; Pătraşcu, Virgil

    2015-01-01

    Oral cancers still represent a major health problem; regional lymph node metastases occur in 30-40% of head and neck squamous cell carcinomas and are associated with unfavorable prognosis and decreased survival. The study included 35 cases of oral squamous cell carcinomas (OSCC), which were analyzed by double reactions to determine the proliferative activity (anti-human D2-40/Ki67) and the maturity degree (anti-human D2-40/α-SMA) of lymphatic vessels, both intratumoral (IT) and in the advancing edge (AE), and in relation to clinicopathological prognostic parameters. The mean values of D2-40 lymphatic vessel density (LVD) were higher in AE then in IT level. Poorly differentiated carcinomas, T3/T4, presented the highest LVD values, both IT and in the AE. LVD was higher in advanced stages and metastasizing carcinomas. Ki67 was positive in all cases, Ki67 proliferation index (IP) indicated higher values in poorly differentiated carcinoma, T3/T4, metastasizing ones, both IT and in the AE. LVD and IP Ki67 showed a positive linear correlation. D2-40/Ki67-positive vessels were identified only at the AE or close to it. D2-40/Ki67 LVD had highest values in advanced stages carcinoma, with metastases. D2-40/α-SMA-positive vessels were identified only in the neighborhood of the tumor and LVD highest values were present in early-stage carcinomas and without metastases. A negative linear correlation between proliferation and maturity of the lymphatic vessels was found. The study indicated a strong association between lymphatic proliferative activity and lymph node metastases, suggesting the need for targeted antilymphangiogenic therapies in OSCC.

  17. The Schlemm’s canal is a VEGF-C/VEGFR-3–responsive lymphatic-like vessel

    PubMed Central

    Aspelund, Aleksanteri; Tammela, Tuomas; Antila, Salli; Nurmi, Harri; Leppänen, Veli-Matti; Zarkada, Georgia; Stanczuk, Lukas; Francois, Mathias; Mäkinen, Taija; Saharinen, Pipsa; Immonen, Ilkka; Alitalo, Kari

    2014-01-01

    In glaucoma, aqueous outflow into the Schlemm’s canal (SC) is obstructed. Despite striking structural and functional similarities with the lymphatic vascular system, it is unknown whether the SC is a blood or lymphatic vessel. Here, we demonstrated the expression of lymphatic endothelial cell markers by the SC in murine and zebrafish models as well as in human eye tissue. The initial stages of SC development involved induction of the transcription factor PROX1 and the lymphangiogenic receptor tyrosine kinase VEGFR-3 in venous endothelial cells in postnatal mice. Using gene deletion and function-blocking antibodies in mice, we determined that the lymphangiogenic growth factor VEGF-C and its receptor, VEGFR-3, are essential for SC development. Delivery of VEGF-C into the adult eye resulted in sprouting, proliferation, and growth of SC endothelial cells, whereas VEGF-A obliterated the aqueous outflow system. Furthermore, a single injection of recombinant VEGF-C induced SC growth and was associated with trend toward a sustained decrease in intraocular pressure in adult mice. These results reveal the evolutionary conservation of the lymphatic-like phenotype of the SC, implicate VEGF-C and VEGFR-3 as critical regulators of SC lymphangiogenesis, and provide a basis for further studies on therapeutic manipulation of the SC with VEGF-C in glaucoma treatment. PMID:25061878

  18. Visualization of fluid drainage pathways in lymphatic vessels and lymph nodes using a mouse model to test a lymphatic drug delivery system.

    PubMed

    Kodama, Tetsuya; Hatakeyama, Yuriko; Kato, Shigeki; Mori, Shiro

    2015-01-01

    Curing/preventing micrometastasis to lymph nodes (LNs) located outside the surgically resected area is essential for improving the morbidity and mortality associated with breast cancer and head and neck cancer. However, no lymphatic therapy system exists that can deliver drugs to LNs located outside the dissection area. Here, we demonstrate proof of concept for a drug delivery system using MXH10/Mo-lpr/lpr mice that exhibit systemic lymphadenopathy, with some peripheral LNs being as large as 10 mm in diameter. We report that a fluorescent solution injected into the subiliac LN (defined as the upstream LN within the dissection area) was delivered successfully to the proper axillary LN (defined as the downstream LN outside the dissection area) through the lymphatic vessels. Our results suggest that this approach could be used before surgical resection to deliver drugs to downstream LNs outside the dissection area. We anticipate that our methodology could be applied clinically, before surgical resection, to cure/prevent micrometastasis in LNs outside the dissection area, using techniques such as ultrasound-guided internal jugular vein catheterization. PMID:25657881

  19. Visualization of fluid drainage pathways in lymphatic vessels and lymph nodes using a mouse model to test a lymphatic drug delivery system.

    PubMed

    Kodama, Tetsuya; Hatakeyama, Yuriko; Kato, Shigeki; Mori, Shiro

    2015-01-01

    Curing/preventing micrometastasis to lymph nodes (LNs) located outside the surgically resected area is essential for improving the morbidity and mortality associated with breast cancer and head and neck cancer. However, no lymphatic therapy system exists that can deliver drugs to LNs located outside the dissection area. Here, we demonstrate proof of concept for a drug delivery system using MXH10/Mo-lpr/lpr mice that exhibit systemic lymphadenopathy, with some peripheral LNs being as large as 10 mm in diameter. We report that a fluorescent solution injected into the subiliac LN (defined as the upstream LN within the dissection area) was delivered successfully to the proper axillary LN (defined as the downstream LN outside the dissection area) through the lymphatic vessels. Our results suggest that this approach could be used before surgical resection to deliver drugs to downstream LNs outside the dissection area. We anticipate that our methodology could be applied clinically, before surgical resection, to cure/prevent micrometastasis in LNs outside the dissection area, using techniques such as ultrasound-guided internal jugular vein catheterization.

  20. Neutrophils rapidly transit inflamed lymphatic vessel endothelium via integrin-dependent proteolysis and lipoxin-induced junctional retraction.

    PubMed

    Rigby, David A; Ferguson, David J P; Johnson, Louise A; Jackson, David G

    2015-12-01

    Neutrophils are the first leukocyte population to be recruited from the circulation following tissue injury or infection, where they play key roles in host defense. However, recent evidence indicates recruited neutrophils can also enter lymph and shape adaptive immune responses downstream in draining lymph nodes. At present, the cellular mechanisms regulating neutrophil entry to lymphatic vessels and migration to lymph nodes are largely unknown. Here, we have investigated these events in an in vivo mouse Mycobacterium bovis bacillus Calmette-Guérin vaccination model, ex vivo mouse dermal explants, and in vitro Transwell system comprising monolayers of primary human dermal lymphatic endothelial cells. We demonstrate that neutrophils are reliant on endothelial activation for adhesion, initially via E-selectin and subsequently, by integrin-mediated binding to ICAM-1 and VCAM-1, combined with CXCL8-dependent chemotaxis. Moreover, we reveal that integrin-mediated neutrophil adhesion plays a pivotal role in subsequent transmigration by focusing the action of matrix metalloproteinases and the 15-lipoxygenase-1-derived chemorepellent 12(S)-hydroxyeicosatetraenoic acid at neutrophil:endothelial contact sites to induce transient endothelial junctional retraction and rapid, selective neutrophil trafficking. These findings reveal an unexpectedly intimate collaboration between neutrophils and the lymphatic vessel endothelium, in which these phagocytic leukocytes act as pathfinders for their own transit during inflammation.

  1. The history of sentinel node biopsy in head and neck cancer: From visualization of lymphatic vessels to sentinel nodes.

    PubMed

    de Bree, Remco; Nieweg, Omgo E

    2015-09-01

    The aim of this report is to describe the history of sentinel node biopsy in head and neck cancer. Sentinel node biopsy is a minimally invasive technique to select patients for treatment of metastatic lymph nodes in the neck. Although this procedure has only recently been accepted for early oral cancer, the first studies on visualization of the cervical lymphatic vessels were reported in the 1960s. In the 1980s mapping of lymphatic drainage from specific head and neck sites was introduced. Sentinel node biopsy was further developed in the 1990s and after validation in this century the procedure is routinely performed in early oral cancer in several head and neck centers. New techniques may improve the accuracy of sentinel node biopsy further, particularly in difficult subsites like the floor of mouth.

  2. Analysis of lymphatic and blood vessel invasion biomarkers in T1 esophagogastric adenocarcinomas for improved patient prognostication.

    PubMed

    Perry, C; Soomro, I; Kaye, P; Hardy, E; Parsons, S L; Ragunath, K; Lobo, D N; Martin, S G; Madhusudan, S

    2015-04-01

    Lymphovascular invasion (LVI) in T1 esophagogastric adenocarcinoma may predict risk of recurrence despite definitive treatment with surgery or endoscopic resection. Podoplanin and CD34 are emerging biomarkers of lymphatic and blood vessel invasion, respectively, and could be adopted to refine LVI assessment. A consecutive series of 65 patients with T1 adenocarcinomas diagnosed at Nottingham University Hospitals were investigated. T1 tumors from 43/65 patients who received primary surgery only were suitable for LVI evaluation by hematoxylin and eosin (H&E) staining as well as by CD34 and Podoplanin immunohistochemistry. LVI was correlated to clinicopathological features and recurrence free survival. H&E staining detected LVI in 11.6% (5/43) of T1 tumors. CD34 and Podoplanin immunohistochemistry significantly improved LVI detection to 25.6% (11/43). Compared with LVI by H&E, immunohistochemical evaluation of blood vessel invasion (CD34) or lymphatic vessel invasion (Podoplanin) was significantly associated with higher grade (P = 0.005), submucosal invasion (T1b) (P = 0.018), lymph node positivity (N1) (P = 0.029) and poor recurrence free survival (P = 0.0003). Our study provides evidence that CD34 and Podoplanin immunohistochemistry could improve LVI detection and allow better prognostication of patients and optimum selection of definitive treatment. Larger multicenter studies are required for further validation that could have significant clinical implications.

  3. 9-Cis Retinoic Acid Promotes Lymphangiogenesis and Enhances Lymphatic Vessel Regeneration: Therapeutic Implications of 9-Cis Retinoic Acid for Secondary Lymphedema

    PubMed Central

    Choi, Inho; Lee, Sunju; Chung, Hee Kyoung; Lee, Yong Suk; Kim, Kyu Eui; Choi, Dongwon; Park, Eun Kyung; Yang, Dongyun; Ecoiffier, Tatiana; Monahan, John; Chen, Wen; Aguilar, Berenice; Lee, Ha Neul; Yoo, Jaehyuk; Koh, Chester J.; Chen, Lu; Wong, Alex K.; Hong, Young-Kwon

    2012-01-01

    Background The lymphatic system plays a key role in tissue fluid homeostasis and lymphatic dysfunction due to genetic defects or lymphatic vessel obstruction can cause lymphedema, disfiguring tissue swellings often associated with fibrosis and recurrent infections without available cures to date. In this study, retinoic acids (RAs) were determined to be a potent therapeutic agent that is immediately applicable to reduce secondary lymphedema. Methods and Results We report that RAs promote proliferation, migration and tube formation of cultured lymphatic endothelial cells (LECs) by activating FGF-receptor signaling. Moreover, RAs control the expression of cell-cycle checkpoint regulators such as p27Kip1, p57Kip2 and the aurora kinases through both an Akt-mediated non-genomic action and a transcription-dependent genomic action that is mediated by Prox1, a master regulator of lymphatic development. Moreover, 9-cisRA was found to activate in vivo lymphangiogenesis in animals based on mouse trachea, matrigel plug and cornea pocket assays. Finally, we demonstrate that 9-cisRA can provide a strong therapeutic efficacy in ameliorating the experimental mouse tail lymphedema by enhancing lymphatic vessel regeneration. Conclusions These in vitro and animal studies demonstrate that 9-cisRA potently activates lymphangiogenesis and promotes lymphatic regeneration in an experimental lymphedema model, presenting it as a promising novel therapeutic agent to treat human lymphedema patients. PMID:22275501

  4. Lymphatics, Cancer and Zebrafish.

    PubMed

    Astin, Jonathan W; Crosier, Philip S

    2016-01-01

    Many solid tumors are known to metastasize through the lymphatic vasculature. This process is facilitated by the generation of new lymphatic vessels (tumor lymphangiogenesis) and also by the remodelling of existing lymphatics. Together these processes enable the spread of tumor cells to distant sites. Currently our understanding of tumor lymphangiogenesis has been informed from mouse tumor models and from studies of developmental lymphangiogenesis. Since the discovery of bona fide lymphatic vessels in zebrafish in 2006, zebrafish have become a well-established model of developmental lymphangiogenesis. The attributes that make zebrafish such an important model of blood vessel development-the ability to live image developing vessels, genetic tractability and the conserved nature of development-also make fish an attractive model of lymphatic vessel development. In particular, zebrafish have made important contributions to our understanding of the processes of lymphatic vessel sprouting from veins and the mechanisms by which lymphatic precursors remodel into mature vessels. To date, zebrafish have not been used to directly model tumor lymphangiogenesis. In this chapter we will summarise the contributions zebrafish have made to our understanding of lymphangiogenesis and investigate the possibilities of combining zebrafish transgenic cancer lines or tumor transplantation models with existing lymphatic reporter lines, which could provide valuable insights into the process of tumor-induced lymphangiogenesis. In addition the utility of using the zebrafish lymphatic model as a platform to screen and develop novel anti-lymphatic therapeutics will also be discussed.

  5. Lymphatics, Cancer and Zebrafish.

    PubMed

    Astin, Jonathan W; Crosier, Philip S

    2016-01-01

    Many solid tumors are known to metastasize through the lymphatic vasculature. This process is facilitated by the generation of new lymphatic vessels (tumor lymphangiogenesis) and also by the remodelling of existing lymphatics. Together these processes enable the spread of tumor cells to distant sites. Currently our understanding of tumor lymphangiogenesis has been informed from mouse tumor models and from studies of developmental lymphangiogenesis. Since the discovery of bona fide lymphatic vessels in zebrafish in 2006, zebrafish have become a well-established model of developmental lymphangiogenesis. The attributes that make zebrafish such an important model of blood vessel development-the ability to live image developing vessels, genetic tractability and the conserved nature of development-also make fish an attractive model of lymphatic vessel development. In particular, zebrafish have made important contributions to our understanding of the processes of lymphatic vessel sprouting from veins and the mechanisms by which lymphatic precursors remodel into mature vessels. To date, zebrafish have not been used to directly model tumor lymphangiogenesis. In this chapter we will summarise the contributions zebrafish have made to our understanding of lymphangiogenesis and investigate the possibilities of combining zebrafish transgenic cancer lines or tumor transplantation models with existing lymphatic reporter lines, which could provide valuable insights into the process of tumor-induced lymphangiogenesis. In addition the utility of using the zebrafish lymphatic model as a platform to screen and develop novel anti-lymphatic therapeutics will also be discussed. PMID:27165355

  6. Interleukin-8 reduces post-surgical lymphedema formation by promoting lymphatic vessel regeneration.

    PubMed

    Choi, Inho; Lee, Yong Suk; Chung, Hee Kyoung; Choi, Dongwon; Ecoiffier, Tatiana; Lee, Ha Neul; Kim, Kyu Eui; Lee, Sunju; Park, Eun Kyung; Maeng, Yong Sun; Kim, Nam Yun; Ladner, Robert D; Petasis, Nicos A; Koh, Chester J; Chen, Lu; Lenz, Heinz-Josef; Hong, Young-Kwon

    2013-01-01

    Lymphedema is mainly caused by lymphatic obstruction and manifested as tissue swelling, often in the arms and legs. Lymphedema is one of the most common post-surgical complications in breast cancer patients and presents a painful and disfiguring chronic illness that has few treatment options. Here, we evaluated the therapeutic potential of interleukin (IL)-8 in lymphatic regeneration independent of its pro-inflammatory activity. We found that IL-8 promoted proliferation, tube formation, and migration of lymphatic endothelial cells (LECs) without activating the VEGF signaling. Additionally, IL-8 suppressed the major cell cycle inhibitor CDKN1C/p57(KIP2) by downregulating its positive regulator PROX1, which is known as the master regulator of LEC-differentiation. Animal-based studies such as matrigel plug and cornea micropocket assays demonstrated potent efficacy of IL-8 in activating lymphangiogenesis in vivo. Moreover, we have generated a novel transgenic mouse model (K14-hIL8) that expresses human IL-8 in the skin and then crossed with lymphatic-specific fluorescent (Prox1-GFP) mouse. The resulting double transgenic mice showed that a stable expression of IL-8 could promote embryonic lymphangiogenesis. Moreover, an immunodeficient IL-8-expressing mouse line that was established by crossing K14-hIL8 mice with athymic nude mice displayed an enhanced tumor-associated lymphangiogenesis. Finally, when experimental lymphedema was introduced, K14-hIL8 mice showed an improved amelioration of lymphedema with an increased lymphatic regeneration. Together, we report that IL-8 can activate lymphangiogenesis in vitro and in vivo with a therapeutic efficacy in post-surgical lymphedema.

  7. Bimodal Expansion of the Lymphatic Vessels Is Regulated by the Sequential Expression of IL-7 and Lymphotoxin α1β2 in Newly Formed Tertiary Lymphoid Structures

    PubMed Central

    Nayar, Saba; Campos, Joana; Chung, Ming May; Navarro-Núñez, Leyre; Chachlani, Menka; Steinthal, Nathalie; Gardner, David H.; Rankin, Philip; Cloake, Thomas; Caamaño, Jorge H.; McGettrick, Helen M.; Watson, Steve P.; Luther, Sanjiv; Buckley, Christopher D.

    2016-01-01

    Lymphangiogenesis associated with tertiary lymphoid structure (TLS) has been reported in numerous studies. However, the kinetics and dynamic changes occurring to the lymphatic vascular network during TLS development have not been studied. Using a viral-induced, resolving model of TLS formation in the salivary glands of adult mice we demonstrate that the expansion of the lymphatic vascular network is tightly regulated. Lymphatic vessel expansion occurs in two distinct phases. The first wave of expansion is dependent on IL-7. The second phase, responsible for leukocyte exit from the glands, is regulated by lymphotoxin (LT)βR signaling. These findings, while highlighting the tight regulation of the lymphatic response to inflammation, suggest that targeting the LTα1β2/LTβR pathway in TLS-associated pathologies might impair a natural proresolving mechanism for lymphocyte exit from the tissues and account for the failure of therapeutic strategies that target these molecules in diseases such as rheumatoid arthritis. PMID:27474071

  8. Ectodomain Shedding of Lymphatic Vessel Endothelial Hyaluronan Receptor 1 (LYVE-1) Is Induced by Vascular Endothelial Growth Factor A (VEGF-A).

    PubMed

    Nishida-Fukuda, Hisayo; Araki, Ryoichi; Shudou, Masachika; Okazaki, Hidenori; Tomono, Yasuko; Nakayama, Hironao; Fukuda, Shinji; Sakaue, Tomohisa; Shirakata, Yuji; Sayama, Koji; Hashimoto, Koji; Detmar, Michael; Higashiyama, Shigeki; Hirakawa, Satoshi

    2016-05-13

    Lymphatic vessel endothelial hyaluronan receptor 1 (LYVE-1), a type I transmembrane glycoprotein, is known as one of the most specific lymphatic vessel markers in the skin. In this study, we found that the ectodomain of LYVE-1 undergoes proteolytic cleavage, and this process produces soluble LYVE-1. We further identified the cleavage site for ectodomain shedding and generated an uncleavable mutant of LYVE-1. In lymphatic endothelial cells, ectodomain shedding of LYVE-1 was induced by vascular endothelial growth factor (VEGF)-A, an important factor for angiogenesis and lymphangiogenesis under pathological conditions. VEGF-A-induced LYVE-1 ectodomain shedding was mediated via the extracellular signal-regulated kinase (ERK) and a disintegrin and metalloproteinase (ADAM) 17. Wild-type LYVE-1, but not uncleavable LYVE-1, promoted migration of lymphatic endothelial cells in response to VEGF-A. Immunostaining analyses in human psoriasis skin lesions and VEGF-A transgenic mouse skin suggested that the ectodomain shedding of LYVE-1 occurred in lymphatic vessels undergoing chronic inflammation. These results indicate that the ectodomain shedding of LYVE-1 might be involved in promoting pathological lymphangiogenesis.

  9. Podoplanin-Fc reduces lymphatic vessel formation in vitro and in vivo and causes disseminated intravascular coagulation when transgenically expressed in the skin.

    PubMed

    Cueni, Leah N; Chen, Lu; Zhang, Hui; Marino, Daniela; Huggenberger, Reto; Alitalo, Annamari; Bianchi, Roberta; Detmar, Michael

    2010-11-18

    Podoplanin is a small transmembrane protein required for development and function of the lymphatic vascular system. To investigate the effects of interfering with its function, we produced an Fc fusion protein of its ectodomain. We found that podoplanin-Fc inhibited several functions of cultured lymphatic endothelial cells and also specifically suppressed lymphatic vessel growth, but not blood vessel growth, in mouse embryoid bodies in vitro and in mouse corneas in vivo. Using a keratin 14 expression cassette, we created transgenic mice that overexpressed podoplanin-Fc in the skin. No obvious outward phenotype was identified in these mice, but surprisingly, podoplanin-Fc-although produced specifically in the skin-entered the blood circulation and induced disseminated intravascular coagulation, characterized by microthrombi in most organs and by thrombocytopenia, occasionally leading to fatal hemorrhage. These findings reveal an important role of podoplanin in lymphatic vessel formation and indicate the potential of podoplanin-Fc as an inhibitor of lymphangiogenesis. These results also demonstrate the ability of podoplanin to induce platelet aggregation in vivo, which likely represents a major function of lymphatic endothelium. Finally, keratin 14 podoplanin-Fc mice represent a novel genetic animal model of disseminated intravascular coagulation.

  10. Ectodomain Shedding of Lymphatic Vessel Endothelial Hyaluronan Receptor 1 (LYVE-1) Is Induced by Vascular Endothelial Growth Factor A (VEGF-A).

    PubMed

    Nishida-Fukuda, Hisayo; Araki, Ryoichi; Shudou, Masachika; Okazaki, Hidenori; Tomono, Yasuko; Nakayama, Hironao; Fukuda, Shinji; Sakaue, Tomohisa; Shirakata, Yuji; Sayama, Koji; Hashimoto, Koji; Detmar, Michael; Higashiyama, Shigeki; Hirakawa, Satoshi

    2016-05-13

    Lymphatic vessel endothelial hyaluronan receptor 1 (LYVE-1), a type I transmembrane glycoprotein, is known as one of the most specific lymphatic vessel markers in the skin. In this study, we found that the ectodomain of LYVE-1 undergoes proteolytic cleavage, and this process produces soluble LYVE-1. We further identified the cleavage site for ectodomain shedding and generated an uncleavable mutant of LYVE-1. In lymphatic endothelial cells, ectodomain shedding of LYVE-1 was induced by vascular endothelial growth factor (VEGF)-A, an important factor for angiogenesis and lymphangiogenesis under pathological conditions. VEGF-A-induced LYVE-1 ectodomain shedding was mediated via the extracellular signal-regulated kinase (ERK) and a disintegrin and metalloproteinase (ADAM) 17. Wild-type LYVE-1, but not uncleavable LYVE-1, promoted migration of lymphatic endothelial cells in response to VEGF-A. Immunostaining analyses in human psoriasis skin lesions and VEGF-A transgenic mouse skin suggested that the ectodomain shedding of LYVE-1 occurred in lymphatic vessels undergoing chronic inflammation. These results indicate that the ectodomain shedding of LYVE-1 might be involved in promoting pathological lymphangiogenesis. PMID:26966180

  11. Integrin-α5β1 is not required for mural cell functions during development of blood vessels but is required for lymphatic-blood vessel separation and lymphovenous valve formation.

    PubMed

    Turner, Christopher J; Badu-Nkansah, Kwabena; Crowley, Denise; van der Flier, Arjan; Hynes, Richard O

    2014-08-15

    Integrin α5β1 is essential for vascular development but it remains unclear precisely where and how it functions. Here, we report that deletion of the gene encoding the integrin-α5 subunit (Itga5) using the Pdgfrb-Cre transgenic mouse line, leads to oedema, haemorrhage and increased levels of embryonic lethality. Unexpectedly, these defects were not caused by loss of α5 from Pdgfrb-Cre expressing mural cells (pericytes and vascular smooth muscle cells), which wrap around the endothelium and stabilise blood vessels, nor by defects in the heart or great vessels, but were due to abnormal development of the lymphatic vasculature. Reminiscent of the pathologies seen in the human lymphatic malformation, fetal cystic hygroma, α5 mutants display defects both in the separation of their blood and lymphatic vasculature and in the formation of the lymphovenous valves. As a consequence, α5-deficient mice develop dilated, blood-filled lymphatic vessels and lymphatic capillaries that are ectopically covered with smooth muscle cells. Analysis of the expression of Pdgfrb during lymphatic development suggests that these defects probably arise from loss of α5β1 integrin in subsets of specialised Prox1(+)Pdgfrb(+) venous endothelial cells that are essential for the separation of the jugular lymph sac from the cardinal vein and formation of the lymphovenous valve leaflets.

  12. Lymphatic anatomy and biomechanics.

    PubMed

    Negrini, Daniela; Moriondo, Andrea

    2011-06-15

    Lymph formation is driven by hydraulic pressure gradients developing between the interstitial tissue and the lumen of initial lymphatics. While in vessels equipped with lymphatic smooth muscle cells these gradients are determined by well-synchronized spontaneous contractions of vessel segments, initial lymphatics devoid of smooth muscles rely on tissue motion to form lymph and propel it along the network. Lymphatics supplying highly moving tissues, such as skeletal muscle, diaphragm or thoracic tissues, undergo cyclic compression and expansion of their lumen imposed by local stresses arising in the tissue as a consequence of cardiac and respiratory activities. Active muscle contraction and not passive tissue displacement is required to support an efficient lymphatic drainage, as suggested by the fact that the respiratory activity promotes lymph formation during spontaneous, but not mechanical ventilation. The mechanical properties of the lymphatic wall and of the surrounding tissue also play an important role in lymphatic function. Modelling of stress distribution in the lymphatic wall suggests that compliant vessels behave as reservoirs accommodating absorbed interstitial fluid, while lymphatics with stiffer walls, taking advantage of a more efficient transmission of tissue stresses to the lymphatic lumen, propel fluid through the lumen of the lymphatic circuit.

  13. Massive pneumatic expansion of lymphatic vessel resulting in cystic lesions in the pulmonary parenchyma: a rare case of persistent interstitial pulmonary emphysema in a non-ventilated infant.

    PubMed

    Fujishiro, Jun; Komuro, Hiroaki; Ono, Kentaro; Urita, Yasuhisa; Shinkai, Toko; Minami, Yuko; Kawabata, Yoshinori; Kishimoto, Hiroshi; Masumoto, Kouji

    2012-12-01

    We report the case of 2-week-old female infant with cystic lung disease who presented with mild tachypnea and had no history of mechanical ventilation. Chest CT demonstrated multiple air-filled cystic lesions in right upper lobe, and the patient subsequently underwent a right upper lobectomy. Histology revealed cystic lesions located in the pulmonary parenchyma and showed that the lesions were lined by lymphatic endothelium and were communicating with dilated lymphatic vessels in the interstitium. Additionally, multinucleated foreign body giant cells were attached to the lumen of the cyst. On the basis of these findings, we considered this a case of persistent interstitial pulmonary emphysema (PIPE) with massive pneumatic expansion of the lymphatic vessels, resulting in cystic lesions with lymphatic endothelium in the pulmonary parenchyma. While PIPE is extremely rare in term non-ventilated infants, our case demonstrated that this disease should be added to the differential diagnosis of cystic lung diseases with lymphatic endothelium even in infants without mechanical ventilation. When cystic lesions and symptoms persist despite conservative treatment, open or thoracoscopic resection is an appropriate option for diagnosis and treatment.

  14. Regulatory T cell transfer ameliorates lymphedema and promotes lymphatic vessel function

    PubMed Central

    Gousopoulos, Epameinondas; Proulx, Steven T.; Bachmann, Samia B.; Scholl, Jeannette; Dionyssiou, Dimitris; Demiri, Efterpi; Halin, Cornelia; Dieterich, Lothar C.

    2016-01-01

    Secondary lymphedema is a common postcancer treatment complication, but the underlying pathological processes are poorly understood and no curative treatment exists. To investigate lymphedema pathomechanisms, a top-down approach was applied, using genomic data and validating the role of a single target. RNA sequencing of lymphedematous mouse skin indicated upregulation of many T cell–related networks, and indeed depletion of CD4+ cells attenuated lymphedema. The significant upregulation of Foxp3, a transcription factor specifically expressed by regulatory T cells (Tregs), along with other Treg-related genes, implied a potential role of Tregs in lymphedema. Indeed, increased infiltration of Tregs was identified in mouse lymphedematous skin and in human lymphedema specimens. To investigate the role of Tregs during disease progression, loss-of-function and gain-of-function studies were performed. Depletion of Tregs in transgenic mice with Tregs expressing the primate diphtheria toxin receptor and green fluorescent protein (Foxp3-DTR-GFP) mice led to exacerbated edema, concomitant with increased infiltration of immune cells and a mixed TH1/TH2 cytokine profile. Conversely, expansion of Tregs using IL-2/anti–IL-2 mAb complexes significantly reduced lymphedema development. Therapeutic application of adoptively transferred Tregs upon lymphedema establishment reversed all of the major hallmarks of lymphedema, including edema, inflammation, and fibrosis, and also promoted lymphatic drainage function. Collectively, our results reveal that Treg application constitutes a potential new curative treatment modality for lymphedema. PMID:27734032

  15. Transcriptional profile in afferent lymph cells following vaccination with liposomes incorporating CpG

    PubMed Central

    Neeland, Melanie R; Elhay, Martin J; Powell, David R; Rossello, Fernando J; Meeusen, Els N T; de Veer, Michael J

    2015-01-01

    Vaccine formulations incorporating innate immune stimulants are highly immunogenic; however, the biological signals that originate in the peripheral tissues at the site of injection and are transmitted to the local lymph node to induce immunity remain unclear. By directly cannulating the ovine afferent lymphatic vessels, we have previously shown that it takes 72 hr for mature antigen-loaded dendritic cells and monocytes to appear within afferent lymph following injection of a liposomal formulation containing the Toll-like receptor ligand CpG. In this present study, we characterize the global transcriptional signatures at this time-point in ovine afferent lymph cells as they migrate from the injection site into the lymphatics following vaccination with a liposome antigen formulation incorporating CpG. We show that at 72 hr post vaccination, liposomes alone induce no changes in gene expression and inflammatory profiles within afferent lymph; however, the incorporation of CpG drives interferon, antiviral and cytotoxic gene programmes. This study also measures the expression of key genes within individual cell types in afferent lymph. Antiviral gene signatures are most prominent in lymphocytes, which may play a significant and unexpected role in sustaining the immune response to vaccination at the site of injection. These findings provide a comprehensive analysis of the in vivo immunological pathways that connect the injection site with the local draining lymph node following vaccination. PMID:25308816

  16. Mapping superficial lymphatic territories in the rabbit.

    PubMed

    Soto-Miranda, Miguel A; Suami, Hiroo; Chang, David W

    2013-06-01

    Little is known about the anatomy of the lymphatic system in the rabbit with regard to relationships between the lymphatic vessel and lymph node. According to our previous studies in human cadavers and canines, the superficial lymphatic system could be divided into lymphatic territories. The aim of this study was to completely map the superficial lymphatic system in the rabbit. We used our microinjection technique and histological analysis for dissecting studies and recently developed indocyanine green (ICG) fluorescent lymphography for demonstrating dynamic lymph flow in living rabbits. Real-time ICG fluorescent lymphography was performed in two living New Zealand White rabbits, and direct dye microinjection of the lymphatic vessels was performed in eight dead rabbits. To assess the relationships between the vascular and lymphatic systems in rabbits, we performed radiocontrast injection into arteries in two dead rabbits prior to the lymphatic injection. The ICG fluorescent lymphography revealed eight lymphatic territories in the preauricular, submandibular, root of the lateral neck, axillary, lumbar, inguinal, root of the tail, and popliteal regions. We injected blue acrylic dye into every lymphatic vessel 0.1 mm in diameter or larger. We then dissected and chased the stained lymphatic vessels proximally until the vessels connected to the first tier lymph node. This procedure was repeated throughout the body until all the relationships between the lymphatic vessels and lymph nodes were defined. The lymphatic system of the rabbit could be defined as eight lymphatic territories, each with its own lymphatic vessels and lymph node.

  17. Schlemm's canal is a unique vessel with a combination of blood vascular and lymphatic phenotypes that forms by a novel developmental process.

    PubMed

    Kizhatil, Krishnakumar; Ryan, Margaret; Marchant, Jeffrey K; Henrich, Stephen; John, Simon W M

    2014-07-01

    Schlemm's canal (SC) plays central roles in ocular physiology. These roles depend on the molecular phenotypes of SC endothelial cells (SECs). Both the specific phenotype of SECs and development of SC remain poorly defined. To allow a modern and extensive analysis of SC and its origins, we developed a new whole-mount procedure to visualize its development in the context of surrounding tissues. We then applied genetic lineage tracing, specific-fluorescent reporter genes, immunofluorescence, high-resolution confocal microscopy, and three-dimensional (3D) rendering to study SC. Using these techniques, we show that SECs have a unique phenotype that is a blend of both blood and lymphatic endothelial cell phenotypes. By analyzing whole mounts of postnatal mouse eyes progressively to adulthood, we show that SC develops from blood vessels through a newly discovered process that we name "canalogenesis." Functional inhibition of KDR (VEGFR2), a critical receptor in initiating angiogenesis, shows that this receptor is required during canalogenesis. Unlike angiogenesis and similar to stages of vasculogenesis, during canalogenesis tip cells divide and form branched chains prior to vessel formation. Differing from both angiogenesis and vasculogenesis, during canalogenesis SECs express Prox1, a master regulator of lymphangiogenesis and lymphatic phenotypes. Thus, SC development resembles a blend of vascular developmental programs. These advances define SC as a unique vessel with a combination of blood vascular and lymphatic phenotypes. They are important for dissecting its functions that are essential for ocular health and normal vision. PMID:25051267

  18. Binding of Hyaluronan to the Native Lymphatic Vessel Endothelial Receptor LYVE-1 Is Critically Dependent on Receptor Clustering and Hyaluronan Organization*

    PubMed Central

    Lawrance, William; Banerji, Suneale; Day, Anthony J.; Bhattacharjee, Shaumick; Jackson, David G.

    2016-01-01

    The lymphatic endothelial receptor LYVE-1 has been implicated in both uptake of hyaluronan (HA) from tissue matrix and in facilitating transit of leukocytes and tumor cells through lymphatic vessels based largely on in vitro studies with recombinant receptor in transfected fibroblasts. Curiously, however, LYVE-1 in lymphatic endothelium displays little if any binding to HA in vitro, and this has led to the conclusion that the native receptor is functionally silenced, a feature that is difficult to reconcile with its proposed in vivo functions. Nonetheless, as we reported recently, LYVE-1 can function as a receptor for HA-encapsulated Group A streptococci and mediate lymphatic dissemination in mice. Here we resolve these paradoxical findings and show that the capacity of LYVE-1 to bind HA is strictly dependent on avidity, demanding appropriate receptor self-association and/or HA multimerization. In particular, we demonstrate the prerequisite of a critical LYVE-1 threshold density and show that HA binding may be elicited in lymphatic endothelium by surface clustering with divalent LYVE-1 mAbs. In addition, we show that cross-linking of biotinylated HA in streptavidin multimers or supramolecular complexes with the inflammation-induced protein TSG-6 enables binding even in the absence of LYVE-1 cross-linking. Finally, we show that endogenous HA on the surface of macrophages can engage LYVE-1, facilitating their adhesion and transit across lymphatic endothelium. These results reveal LYVE-1 as a low affinity receptor tuned to discriminate between different HA configurations through avidity and establish a new mechanistic basis for the functions ascribed to LYVE-1 in matrix HA binding and leukocyte trafficking in vivo. PMID:26823460

  19. Mechanical forces and lymphatic transport.

    PubMed

    Breslin, Jerome W

    2014-11-01

    This review examines the current understanding of how the lymphatic vessel network can optimize lymph flow in response to various mechanical forces. Lymphatics are organized as a vascular tree, with blind-ended initial lymphatics, precollectors, prenodal collecting lymphatics, lymph nodes, postnodal collecting lymphatics and the larger trunks (thoracic duct and right lymph duct) that connect to the subclavian veins. The formation of lymph from interstitial fluid depends heavily on oscillating pressure gradients to drive fluid into initial lymphatics. Collecting lymphatics are segmented vessels with unidirectional valves, with each segment, called a lymphangion, possessing an intrinsic pumping mechanism. The lymphangions propel lymph forward against a hydrostatic pressure gradient. Fluid is returned to the central circulation both at lymph nodes and via the larger lymphatic trunks. Several recent developments are discussed, including evidence for the active role of endothelial cells in lymph formation; recent developments on how inflow pressure, outflow pressure, and shear stress affect the pump function of the lymphangion; lymphatic valve gating mechanisms; collecting lymphatic permeability; and current interpretations of the molecular mechanisms within lymphatic endothelial cells and smooth muscle. An improved understanding of the physiological mechanisms by which lymphatic vessels sense mechanical stimuli, integrate the information, and generate the appropriate response is key for determining the pathogenesis of lymphatic insufficiency and developing treatments for lymphedema. PMID:25107458

  20. Mechanical Forces and Lymphatic Transport

    PubMed Central

    Breslin, Jerome W.

    2014-01-01

    This review examines current understanding of how the lymphatic vessel network can optimize lymph flow in response to various mechanical forces. Lymphatics are organized as a vascular tree, with blind-ended initial lymphatics, precollectors, prenodal collecting lymphatics, lymph nodes, postnodal collecting lymphatics and the larger trunks (thoracic duct and right lymph duct) that connect to the subclavian veins. The formation of lymph from interstitial fluid depends heavily on oscillating pressure gradients to drive fluid into initial lymphatics. Collecting lymphatics are segmented vessels with unidirectional valves, with each segment, called a lymphangion, possessing an intrinsic pumping mechanism. The lymphangions propel lymph forward against a hydrostatic pressure gradient. Fluid is returned to the central circulation both at lymph nodes and via the larger lymphatic trunks. Several recent developments are discussed, including: evidence for the active role of endothelial cells in lymph formation; recent developments on how inflow pressure, outflow pressure, and shear stress affect pump function of the lymphangion; lymphatic valve gating mechanisms; collecting lymphatic permeability; and current interpretations of the molecular mechanisms within lymphatic endothelial cells and smooth muscle. Improved understanding of the physiological mechanisms by lymphatic vessels sense mechanical stimuli, integrate the information, and generate the appropriate response is key for determining the pathogenesis of lymphatic insufficiency and developing treatments for lymphedema. PMID:25107458

  1. Mechanical forces and lymphatic transport.

    PubMed

    Breslin, Jerome W

    2014-11-01

    This review examines the current understanding of how the lymphatic vessel network can optimize lymph flow in response to various mechanical forces. Lymphatics are organized as a vascular tree, with blind-ended initial lymphatics, precollectors, prenodal collecting lymphatics, lymph nodes, postnodal collecting lymphatics and the larger trunks (thoracic duct and right lymph duct) that connect to the subclavian veins. The formation of lymph from interstitial fluid depends heavily on oscillating pressure gradients to drive fluid into initial lymphatics. Collecting lymphatics are segmented vessels with unidirectional valves, with each segment, called a lymphangion, possessing an intrinsic pumping mechanism. The lymphangions propel lymph forward against a hydrostatic pressure gradient. Fluid is returned to the central circulation both at lymph nodes and via the larger lymphatic trunks. Several recent developments are discussed, including evidence for the active role of endothelial cells in lymph formation; recent developments on how inflow pressure, outflow pressure, and shear stress affect the pump function of the lymphangion; lymphatic valve gating mechanisms; collecting lymphatic permeability; and current interpretations of the molecular mechanisms within lymphatic endothelial cells and smooth muscle. An improved understanding of the physiological mechanisms by which lymphatic vessels sense mechanical stimuli, integrate the information, and generate the appropriate response is key for determining the pathogenesis of lymphatic insufficiency and developing treatments for lymphedema.

  2. The lymphatic vasculature in disease.

    PubMed

    Alitalo, Kari

    2011-11-07

    Blood vessels form a closed circulatory system, whereas lymphatic vessels form a one-way conduit for tissue fluid and leukocytes. In most vertebrates, the main function of lymphatic vessels is to collect excess protein-rich fluid that has extravasated from blood vessels and transport it back into the blood circulation. Lymphatic vessels have an important immune surveillance function, as they import various antigens and activated antigen-presenting cells into the lymph nodes and export immune effector cells and humoral response factors into the blood circulation. Defects in lymphatic function can lead to lymph accumulation in tissues, dampened immune responses, connective tissue and fat accumulation, and tissue swelling known as lymphedema. This review highlights the most recent developments in lymphatic biology and how the lymphatic system contributes to the pathogenesis of various diseases involving immune and inflammatory responses and its role in disseminating tumor cells.

  3. Effects of acute exercise, exercise training, and diabetes on the expression of lymphangiogenic growth factors and lymphatic vessels in skeletal muscle.

    PubMed

    Kivelä, Riikka; Silvennoinen, Mika; Lehti, Maarit; Kainulainen, Heikki; Vihko, Veikko

    2007-10-01

    Blood and lymphatic vessels together form the circulatory system, allowing the passage of fluids and molecules within the body. Recently we showed that lymphatic capillaries are also found in the capillary bed of skeletal muscle. Exercise is known to induce angiogenesis in skeletal muscle, but it is not known whether exercise has effects on lymphangiogenesis or lymphangiogenic growth factors. We studied lymphatic vessel density and expression of the main lymphangiogenic growth factors VEGF-C and VEGF-D and their receptor VEGFR-3 in response to acute running exercise and endurance exercise training in the skeletal muscle of healthy and diabetic mice. VEGF-C mRNA expression increased after the acute exercise bout (P < 0.05) in healthy muscles, but there was no change in diabetic muscles. VEGF-C levels were not changed either in healthy or in diabetic muscle after the exercise training. Neither acute exercise nor exercise training had an effect on the mRNA expression of VEGF-D or VEGFR-3 in healthy or diabetic muscles. Lymphatic vessel density was similar in sedentary and trained mice and was >10-fold smaller than blood capillary density. Diabetes increased the mRNA expression of VEGF-D (P < 0.01). Increased immunohistochemical staining of VEGF-D was found in degenerative muscle fibers in the diabetic mice. In conclusion, the results suggest that acute exercise or exercise training does not significantly affect lymphangiogenesis in skeletal muscle. Diabetes increased the expression of VEGF-D in skeletal muscle, and this increase may be related to muscle fiber damage.

  4. Clinical significance of detecting lymphatic and blood vessel invasion in stage II colon cancer using markers D2-40 and CD34 in combination.

    PubMed

    Lai, Jin-Huo; Zhou, Yong-Jian; Bin, Du; Qiangchen; Wang, Shao-Yuan

    2014-01-01

    This research was conducted to compare differences in colon cancer lymphatic vessel invasion (LVI) with D2-40 antibody labeling and regular HE staining, blood vessel invasion (BVI) with CD34 antibody labeling and HE staining and to assess the possibility of using D2-40-LVI/CD34-BVI in combination for predicting stage II colon cancer prognosis and guiding adjuvant chemotherapy.Anti-D2-40 and anti-CD34 antibodies were applied to tissue samples of 220 cases of stage II colon cancer to label lymphatic vessels and small blood vessels, respectively. LVI and BVI were assessed and multivariate COX regression analysis was performed for associations with colon cancer prognosis. Regular HE staining proved unable to differentiate lymphatic vessels from blood vessels, while D2-40 selectively labeled lymphatic endothelial cell cytosol and CD34 was widely expressed in large and small blood vessels of tumors as well as normal tissues. Compared to regular HE staining, D2-40-labeling for LVI and CD34-labeling for BVI significantly increased positive rate (22.3% vs 10.0% for LVI, and 19.1% vs 9.1% for BVI). Multivariate analysis indicated that TNM stage, pathology tissue type, post-surgery adjuvant chemotherapy, D2-40-LVI, and CD34-BVI were independent factors affecting whole group colon cancer prognosis, while HE staining-BVI, HE staining-LVI were not significantly related. When CD34-BVI/D2-40-LVI were used in combination for detection, the risk of death for patients with two or one positive results was 5.003 times that in the LVI(-)andBVI(-) group (95% CI 2.365 - 9.679). D2-40 antibody LVI labeling and CD34 antibody BVI labeling have higher specificity and accuracy than regular HE staining and can be used as molecular biological indicators for prognosis prediction and guidance of adjuvant chemotherapy for stage II colon cancer.

  5. Podoplanin is a component of extracellular vesicles that reprograms cell-derived exosomal proteins and modulates lymphatic vessel formation

    PubMed Central

    Andrés, Germán; Gopal, Shashi K.; Martín-Villar, Ester; Renart, Jaime; Simpson, Richard J.; Quintanilla, Miguel

    2016-01-01

    Podoplanin (PDPN) is a transmembrane glycoprotein that plays crucial roles in embryonic development, the immune response, and malignant progression. Here, we report that cells ectopically or endogenously expressing PDPN release extracellular vesicles (EVs) that contain PDPN mRNA and protein. PDPN incorporates into membrane shed microvesicles (MVs) and endosomal-derived exosomes (EXOs), where it was found to colocalize with the canonical EV marker CD63 by immunoelectron microscopy. We have previously found that expression of PDPN in MDCK cells induces an epithelial-mesenchymal transition (EMT). Proteomic profiling of MDCK-PDPN cells compared to control cells shows that PDPN-induced EMT is associated with upregulation of oncogenic proteins and diminished expression of tumor suppressors. Proteomic analysis of exosomes reveals that MDCK-PDPN EXOs were enriched in protein cargos involved in cell adhesion, cytoskeletal remodeling, signal transduction and, importantly, intracellular trafficking and EV biogenesis. Indeed, expression of PDPN in MDCK cells stimulated both EXO and MV production, while knockdown of endogenous PDPN in human HN5 squamous carcinoma cells reduced EXO production and inhibited tumorigenesis. EXOs released from MDCK-PDPN and control cells both stimulated in vitro angiogenesis, but only EXOs containing PDPN were shown to promote lymphatic vessel formation. This effect was mediated by PDPN on the surface of EXOs, as demonstrated by a neutralizing specific monoclonal antibody. These results contribute to our understanding of PDPN-induced EMT in association to tumor progression, and suggest an important role for PDPN in EV biogenesis and/or release and for PDPN-EXOs in modulating lymphangiogenesis. PMID:26893367

  6. The detection and role of lymphatic and blood vessel invasion in predicting survival in patients with node negative operable primary colorectal cancer.

    PubMed

    van Wyk, Hester C; Roxburgh, Campbell S; Horgan, Paul G; Foulis, Alan F; McMillan, Donald C

    2014-04-01

    Although vascular invasion in colorectal cancer has been recognised since 1938, detection methods and results remain inconsistent. Vascular invasion is currently an independent prognostic factor in colorectal cancer influencing disease progression and survival. The vascular system consists of three components, arterial, venous and lymphatic vessels, all of which can be invaded but accurate distinction between the components remains difficult with routine staining techniques. Even though higher detection rates with elastica staining, for large vessel invasion, and recent techniques for immunohistochemistry for small vessel invasion, have been reported, a standardised method of detection has not been agreed upon which is reflected in the variability of published results. As a result of the Bowel Cancer Screening Programme in the UK it will be necessary to attempt to identify and stratify patients better, to be able to handle the stage migration to early node negative colorectal cancer. At present up to a third of patients, with node-negative colorectal cancer on conventional histopathological analysis, ultimately die of recurrent disease. It is therefore important to develop and standardised methods to identify lymphatic and blood vessel invasion which will influence ultimate survival. The present review summarises the current status of detection methods for these components of vascular invasion.

  7. In vivo label-free monitoring microvascular and lymphatic vessel changes and dynamics during wound healing in mouse ear pinna using optical microangiography

    NASA Astrophysics Data System (ADS)

    Yousefi, Siavash; Wang, Ruikang K.

    2014-02-01

    Cutaneous wound healing consists of multiple overlapping phases starting with blood coagulation following incision of blood vessels. In this paper, we briefly review wound healing phases that were observed by utilizing optical microangiography (OMAG) to monitor healing process and dynamics of microcirculation system in a mouse ear pinna wound model. Mouse ear pinna is composed of two layers of skin separated by a layer of cartilage and because its total thickness is around 500 μm, can be utilized as an ideal model for optical imaging techniques. These skin layers are identical to human skin structure except for sweat ducts and glands. Microcirculatory system responds to the wound injury by recruiting collateral vessels to supply blood flow to hypoxic area. Also, lymphatic vessels play an important role in the immune response of the tissue and clearing waste from interstitial fluid.

  8. Mechanobiology of lymphatic contractions.

    PubMed

    Munn, Lance L

    2015-02-01

    The lymphatic system is responsible for controlling tissue fluid pressure by facilitating flow of lymph (i.e. the plasma and cells that enter the lymphatic system). Because lymph contains cells of the immune system, its transport is not only important for fluid homeostasis, but also immune function. Lymph drainage can occur via passive flow or active pumping, and much research has identified the key biochemical and mechanical factors that affect output. Although many studies and reviews have addressed how tissue properties and fluid mechanics (i.e. pressure gradients) affect lymph transport [1-3] there is less known about lymphatic mechanobiology. As opposed to passive mechanical properties, mechanobiology describes the active coupling of mechanical signals and biochemical pathways. Lymphatic vasomotion is the result of a fascinating system affected by mechanical forces exerted by the flowing lymph, including pressure-induced vessel stretch and flow-induced shear stresses. These forces can trigger or modulate biochemical pathways important for controlling the lymphatic contractions. Here, I review the current understanding of lymphatic vessel function, focusing on vessel mechanobiology, and summarize the prospects for a comprehensive understanding that integrates the mechanical and biomechanical control mechanisms in the lymphatic system.

  9. Lymphatics and blood vessels.

    PubMed

    Millikan, Larry E

    2011-01-01

    The traditional nomenclature of vascular lesions has been enlarged and modified with the usage of newer diagnostic techniques. Digital technology has enhanced the precision of older analog tools such as Doppler flow studies. Angiograms have also more precisely delineated flow patterns to allow planned surgical intervention as an important therapeutic option. With the newer classification, it now is possible to plan and anticipate the course of lesions and medically intervene in tumors that potentially will enlarge and impinge on essential structures. Now, the routine workup will clarify if there is internal involvement (eg, liver, etc) and detect proliferative potential mandating medical or surgical intervention. Watchful waiting, the traditional approach is now changing with the newer delineation of syndromes such as PHACE (posterior fossa, hemangioma, arterial lesions, cardiac abnormalities/aortic coarctation, eye abnormalities), which mandate the fullest evaluation and, in many instances, the collaboration of multispecialty groups to treat those lesions as the data and group consensus determines.

  10. The role of lymphatic and blood vessel invasion in predicting survival and methods of detection in patients with primary operable breast cancer.

    PubMed

    Gujam, Fadia J A; Going, James J; Edwards, Joanne; Mohammed, Zahra M A; McMillan, Donald C

    2014-02-01

    Lymphovascular invasion (LBVI) has long been recognized as an essential step of metastases in patients with cancer. However, the process of invasion into lymphatic and blood vessels is still not well defined in breast cancer. To examine the evidence for LBVI, lymphatic vessel invasion (LVI) and blood vessel invasion (BVI) in predicting survival in patients with primary operable breast cancer, and to evaluate the detection methods of vessel invasion. A systematic review of data published from 1964 to 2012 was undertaken according to a pre-defined protocol. There is robust evidence that general LBVI and LVI are independent prognostic factors of poorer survival. The prognostic role of BVI remains unclear. Most studies detected LBVI using H&E stained sections. The overall weighted average of the LBVI rate using immunostaining was higher (35%) than H&E (24%). The LBVI rate using H&E was variable (9-50%) and less variable using immunostaining (32-41%). The overall weighted average of the LVI rate was similar using H&E and immunostaining (33% vs. 25%). The LVI rate using H&E was variable (10-49%) and less variable using immunostaining (21-42%). The overall weighted average of the BVI rate was similar using H&E and/or classical staining and immunostaining (16% vs. 10%). The BVI rates using H&E and/or classical staining approach (4-46%) and immunostaining (1-29%) were both variable. The LBVI and LVI are powerful prognostic factors in primary operable breast cancer. However, BVI was rarely specifically examined and its role in predicting survival is not clear. Further work is required using reliable specific staining to establish the routine use of LVI and BVI in the prediction of outcome in patients with primary operable breast cancer.

  11. Lymphatic Diseases

    MedlinePlus

    The lymphatic system is a network of tissues and organs. It is made up of Lymph - a fluid that contains ... They are part of the system, too. The lymphatic system clears away infection and keeps your body fluids ...

  12. Lymphatic obstruction

    MedlinePlus

    ... certain directions based on the structure of the lymphatic system. This helps the lymph fluid drain through the ... always appropriate or effective. Alternative Names Lymphedema Images Lymphatic system Yellow nail syndrome References Kurklinsky AK, Rooke TW. ...

  13. Fluid-solid modeling of lymphatic valves

    NASA Astrophysics Data System (ADS)

    Caulk, Alexander; Ballard, Matthew; Nepiyushchikh, Zhanna; Dixon, Brandon; Alexeev, Alexander

    2015-11-01

    The lymphatic system performs important physiological functions such as the return of interstitial fluid to the bloodstream to maintain tissue fluid balance, as well as the transport of immune cells in the body. It utilizes contractile lymphatic vessels, which contain valves that open and close to allow flow in only one direction, to directionally pump lymph against a pressure gradient. We develop a fluid-solid model of geometrically representative lymphatic valves. Our model uses a hybrid lattice-Boltzmann lattice spring method to capture fluid-solid interactions with two-way coupling between a viscous fluid and lymphatic valves in a lymphatic vessel. We use this model to investigate the opening and closing of lymphatic valves, and its effect on lymphatic pumping. This helps to broaden our understanding of the fluid dynamics of the lymphatic system.

  14. Impaired lymphatic contraction associated with immunosuppression.

    PubMed

    Liao, Shan; Cheng, Gang; Conner, David A; Huang, Yuhui; Kucherlapati, Raju S; Munn, Lance L; Ruddle, Nancy H; Jain, Rakesh K; Fukumura, Dai; Padera, Timothy P

    2011-11-15

    To trigger an effective immune response, antigen and antigen-presenting cells travel to the lymph nodes via collecting lymphatic vessels. However, our understanding of the regulation of collecting lymphatic vessel function and lymph transport is limited. To dissect the molecular control of lymphatic function, we developed a unique mouse model that allows intravital imaging of autonomous lymphatic vessel contraction. Using this method, we demonstrated that endothelial nitric oxide synthase (eNOS) in lymphatic endothelial cells is required for robust lymphatic contractions under physiological conditions. By contrast, under inflammatory conditions, inducible NOS (iNOS)-expressing CD11b(+)Gr-1(+) cells attenuate lymphatic contraction. This inhibition of lymphatic contraction was associated with a reduction in the response to antigen in a model of immune-induced multiple sclerosis. These results suggest the suppression of lymphatic function by the CD11b(+)Gr-1(+) cells as a potential mechanism of self-protection from autoreactive responses during on-going inflammation. The central role for nitric oxide also suggests that other diseases such as cancer and infection may also mediate lymphatic contraction and thus immune response. Our unique method allows the study of lymphatic function and its molecular regulation during inflammation, lymphedema, and lymphatic metastasis.

  15. Nitric oxide permits hypoxia-induced lymphatic perfusion by controlling arterial-lymphatic conduits in zebrafish and glass catfish

    PubMed Central

    Dahl Ejby Jensen, Lasse; Cao, Renhai; Hedlund, Eva-Maria; Söll, Iris; Lundberg, Jon O.; Hauptmann, Giselbert; Steffensen, John Fleng; Cao, Yihai

    2009-01-01

    The blood and lymphatic vasculatures are structurally and functionally coupled in controlling tissue perfusion, extracellular interstitial fluids, and immune surveillance. Little is known, however, about the molecular mechanisms that underlie the regulation of bloodlymphatic vessel connections and lymphatic perfusion. Here we show in the adult zebrafish and glass catfish (Kryptopterus bicirrhis) that blood-lymphatic conduits directly connect arterial vessels to the lymphatic system. Under hypoxic conditions, arterial-lymphatic conduits (ALCs) became highly dilated and linearized by NO-induced vascular relaxation, which led to blood perfusion into the lymphatic system. NO blockage almost completely abrogated hypoxia-induced ALC relaxation and lymphatic perfusion. These findings uncover mechanisms underlying hypoxia-induced oxygen compensation by perfusion of existing lymphatics in fish. Our results might also imply that the hypoxia-induced NO pathway contributes to development of progression of pathologies, including promotion of lymphatic metastasis by modulating arterial-lymphatic conduits, in the mammalian system. PMID:19822749

  16. Lymphatic Regulation of Cellular Trafficking

    PubMed Central

    Jackson, David G.

    2016-01-01

    Lymphatic vessels play vital roles in immune surveillance and immune regulation by conveying antigen loaded dendritic cells, memory T cells, macrophages and neutrophils from the peripheral tissues to draining lymph nodes where they initiate as well as modify immune responses. Until relatively recently however, there was little understanding of how entry and migration through lymphatic vessels is organized or the specific molecular mechanisms that might be involved. Within the last decade, the situation has been transformed by an explosion of knowledge generated largely through the application of microscopic imaging, transgenic animals, specific markers and function blocking mAbs that is beginning to provide a rational conceptual framework. This article provides a critical review of the recent literature, highlighting seminal discoveries that have revealed the fascinating ultrastructure of leucocyte entry sites in lymphatic vessels, as well as generating controversies over the involvement of integrin adhesion, chemotactic and haptotactic mechanisms in DC entry under normal and inflamed conditions. It also discusses the major changes in lymphatic architecture that occur during inflammation and the different modes of leucocyte entry and trafficking within inflamed lymphatic vessels, as well as presenting a timely update on the likely role of hyaluronan and the major lymphatic endothelial hyaluronan receptor LYVE-1 in leucocyte transit.

  17. Development of the lymphatic system: new questions and paradigms.

    PubMed

    Semo, Jonathan; Nicenboim, Julian; Yaniv, Karina

    2016-03-15

    The lymphatic system is a blind-ended network of vessels that plays important roles in mediating tissue fluid homeostasis, intestinal lipid absorption and the immune response. A profound understanding of the development of lymphatic vessels, as well as of the molecular cues governing their formation and morphogenesis, might prove essential for our ability to treat lymphatic-related diseases. The embryonic origins of lymphatic vessels have been debated for over a century, with a model claiming a venous origin for the lymphatic endothelium being predominant. However, recent studies have provided new insights into the origins of lymphatic vessels. Here, we review the molecular mechanisms controlling lymphatic specification and sprouting, and we discuss exciting findings that shed new light on previously uncharacterized sources of lymphatic endothelial cells.

  18. Role of lymphatic vasculature in regional and distant metastases.

    PubMed

    Podgrabinska, Simona; Skobe, Mihaela

    2014-09-01

    In cancer, lymphatic vasculature has been traditionally viewed only as a transportation system for metastatic cells. It has now become clear that lymphatics perform many additional functions which could influence cancer progression. Lymphangiogenesis, induced at the primary tumor site and at distant sites, potently augments metastasis. Lymphatic endothelial cells (LECs) control tumor cell entry and exit from the lymphatic vessels. LECs also control immune cell traffic and directly modulate adaptive immune responses. This review highlights advances in our understanding of the mechanisms by which lymphatic vessels, and in particular lymphatic endothelium, impact metastasis.

  19. Lymphatic endothelial lineage assemblage during corneal lymphangiogenesis

    PubMed Central

    Connor, Alicia L.; Kelley, Philip M.; Tempero, Richard M.

    2015-01-01

    Post natal inflammatory lymphangiogenesis presumably requires precise regulatory processes to properly assemble proliferating lymphatic endothelial cells (LECs). The specific mechanisms that regulate the assembly of LECs during new lymphatic vessel synthesis are unclear. Dynamic endothelial shuffling and rearrangement has been proposed as a mechanism of blood vessel growth. We developed genetic lineage tracing strategies using an inductive transgenic technology to track the fate of entire tandem dimer tomato positive (tdT) lymphatic vessels or small, in some cases clonal, populations of LECs. We coupled this platform with a suture induced mouse model of corneal lymphangiogenesis and used different analytic microscopy techniques including serial live imaging to study the spatial properties of proliferating tdT+ LEC progenies. LEC precursors and their progeny expanded from the corneal limbal lymphatic vessel and were assembled contiguously to comprise a subunit within a new lymphatic vessel. VE-cadherin blockade induced morphologic abnormalities in newly synthesized lymphatic vessels, but did not disrupt the tdT+ lymphatic endothelial lineage assembly. Analysis of this static and dynamic data based largely on direct in vivo observations supports a model of lymphatic endothelial lineage assemblage during corneal inflammatory lymphangiogenesis. PMID:26658452

  20. Lymphatic endothelial lineage assemblage during corneal lymphangiogenesis.

    PubMed

    Connor, Alicia L; Kelley, Philip M; Tempero, Richard M

    2016-03-01

    Postnatal inflammatory lymphangiogenesis presumably requires precise regulatory processes to properly assemble proliferating lymphatic endothelial cells (LECs). The specific mechanisms that regulate the assembly of LECs during new lymphatic vessel synthesis are unclear. Dynamic endothelial shuffling and rearrangement has been proposed as a mechanism of blood vessel growth. We developed genetic lineage-tracing strategies using an inductive transgenic technology to track the fate of entire tandem dimer tomato-positive (tdT) lymphatic vessels or small, in some cases clonal, populations of LECs. We coupled this platform with a suture-induced mouse model of corneal lymphangiogenesis and used different analytic microscopy techniques including serial live imaging to study the spatial properties of proliferating tdT(+) LEC progenies. LEC precursors and their progeny expanded from the corneal limbal lymphatic vessel and were assembled contiguously to comprise a subunit within a new lymphatic vessel. VE-cadherin blockade induced morphologic abnormalities in newly synthesized lymphatic vessels, but did not disrupt the tdT(+) lymphatic endothelial lineage assembly. Analysis of this static and dynamic data based largely on direct in vivo observations supports a model of lymphatic endothelial lineage assemblage during corneal inflammatory lymphangiogenesis. PMID:26658452

  1. Lymphatic Vascular Response to Acute Inflammation

    PubMed Central

    Lachance, Pier-Anne; Hazen, Amy; Sevick-Muraca, Eva M.

    2013-01-01

    During acute inflammation, functioning lymphatics are believed to reduce edema and to provide a transiting route for immune cells, but the extent at which the dermal lymphatic remodeling impacts lymphatic transport or the factors regulating these changes remains unclear. Herein we quantify the increase in lymphatic endothelial cells (LECs) and examine the expression of pro-angiogenenic and lymphangiogenic factors during acute cutaneous hypersensitivity (CHS). We found that LECs actively proliferate during CHS but that this proliferation does not affect the lymphatic vessel density. Instead, lymphatic remodeling is accompanied by lymphatic vessel leakiness and lower ejection of lymph fluid, which is observed only in the proximal lymphatic vessel draining the inflamed area. LECs and the immune cells release growth factors and cytokines during inflammation, which impact the lymphatic microenvironment and function. We identified that FGF-2, PLGF-2, HGF, EGF, and KC/CXCL17 are differentially expressed within tissues during acute CHS, but both VEGF-C and VEGF-D levels do not significantly change. Our results indicate that VEGF-C and VEGF-D are not the only players and other factors may be responsible for the LECs proliferation and altered lymphatic function in acute CHS. PMID:24086691

  2. Lymphatic Filariasis

    MedlinePlus

    ... Search The CDC Cancel Submit Search The CDC Parasites - Lymphatic Filariasis Note: Javascript is disabled or is ... this? Submit Button Information For: Travelers Related Links Parasites A-Z Index Parasites Glossary Neglected Tropical Diseases ...

  3. Lymphangiogenesis, Lymphatic Endothelial Cells and Lymphatic Metastasis in Head and Neck Cancer — A Review of Mechanisms

    PubMed Central

    Zhang, Zhuang; Helman, Joseph I; Li, Long-jiang

    2010-01-01

    Lymphatic metastasis is a continuous and complicated process. The detailed mechanisms of lymphatic metastasis are still not very clear, despite considerable research efforts in recent years. Previously, it was commonly accepted that there were no lymphatic vessels in the primary tumor. However, recent studies have demonstrated that lymphatic vessels are detectable in certain types of cancer, and more and more evidence has shown that cancer cells invade into local lymph nodes mainly via peritumoral lymphatic vessels. Moreover, activated endothelial cells may also be important, having an influence on lymphatic metastasis of cancer cells. This article, based on recent research findings, provides an in-depth discussion of the relationship between lymphangiogenesis, tumor-derived lymphatic endothelial cells and lymphatic metastasis in head and neck cancer. PMID:20690413

  4. Increased Detection of Lymphatic Vessel Invasion by D2-40 (Podoplanin) in Early Breast Cancer: Possible Influence on Patient Selection for Accelerated Partial Breast Irradiation

    SciTech Connect

    Debald, Manuel; Poelcher, Martin; Flucke, Uta; Walgenbach-Bruenagel, Gisela

    2010-07-15

    Purpose: Several international trials are currently investigating accelerated partial breast irradiation (APBI) for patients with early-stage breast cancer. According to existing guidelines, patients with lymphatic vessel invasion (LVI) do not qualify for APBI. D2-40 (podoplanin) significantly increases the frequency of LVI detection compared with conventional hematoxylin and eosin (HE) staining in early-stage breast cancer. Our purpose was to retrospectively assess the hypothetical change in management from APBI to whole breast radiotherapy with the application of D2-40. Patients and Methods: Immunostaining with D2-40 was performed on 254 invasive breast tumors of 247 patients. The following criteria were used to determine the eligibility for APBI: invasive ductal adenocarcinoma of {<=}3 cm, negative axillary node status (N0), and unifocal disease. Of the 247 patients, 74 with available information concerning LVI, as detected by D2-40 immunostaining and routine HE staining, formed our study population. Results: Using D2-40, our results demonstrated a significantly greater detection rate (p = .031) of LVI compared with routine HE staining. LVI was correctly identified by D2-40 (D2-40-positive LVI) in 10 (13.5%) of 74 tumors. On routine HE staining, 4 tumors (5.4%) were classified as HE-positive LVI. Doublestaining of these specimens with D2-40 unmasked false-positive LVI status in 2 (50%) of the 4 tumors. According to the current recommendations for APBI, immunostaining with D2-40 would have changed the clinical management from APBI to whole breast radiotherapy in 8 (10.8%) of 74 patients and from whole breast radiotherapy to APBI in 2 patients (2.7%). Conclusion: These data support the implementation of D2-40 immunostaining in the routine workup to determine a patient's eligibility for APBI.

  5. Pkd1 regulates lymphatic vascular morphogenesis during development.

    PubMed

    Coxam, Baptiste; Sabine, Amélie; Bower, Neil I; Smith, Kelly A; Pichol-Thievend, Cathy; Skoczylas, Renae; Astin, Jonathan W; Frampton, Emmanuelle; Jaquet, Muriel; Crosier, Philip S; Parton, Robert G; Harvey, Natasha L; Petrova, Tatiana V; Schulte-Merker, Stefan; Francois, Mathias; Hogan, Benjamin M

    2014-05-01

    Lymphatic vessels arise during development through sprouting of precursor cells from veins, which is regulated by known signaling and transcriptional mechanisms. The ongoing elaboration of vessels to form a network is less well understood. This involves cell polarization, coordinated migration, adhesion, mixing, regression, and shape rearrangements. We identified a zebrafish mutant, lymphatic and cardiac defects 1 (lyc1), with reduced lymphatic vessel development. A mutation in polycystic kidney disease 1a was responsible for the phenotype. PKD1 is the most frequently mutated gene in autosomal dominant polycystic kidney disease (ADPKD). Initial lymphatic precursor sprouting is normal in lyc1 mutants, but ongoing migration fails. Loss of Pkd1 in mice has no effect on precursor sprouting but leads to failed morphogenesis of the subcutaneous lymphatic network. Individual lymphatic endothelial cells display defective polarity, elongation, and adherens junctions. This work identifies a highly selective and unexpected role for Pkd1 in lymphatic vessel morphogenesis during development.

  6. Lymphatic Territories (Lymphosomes) in a Canine: An Animal Model for Investigation of Postoperative Lymphatic Alterations

    PubMed Central

    Suami, Hiroo; Yamashita, Shuji; Soto-Miranda, Miguel A.; Chang, David W.

    2013-01-01

    Background Lymph node dissection is often performed as a part of surgical treatment for breast cancer and malignant melanoma to prevent malignant cells from traveling via the lymphatic system. Currently little is known about postoperative lymphatic drainage pattern alterations. This knowledge may be useful for management of recurrent cancer and prevention of breast cancer related lymphedema. We mapped the complete superficial lymphatic system of a dog and used this canine model to perform preliminary studies of lymphatic architectural changes in postoperative condition. Methods Lymphatic territories (lymphosomes) were mapped with 4 female mongrel carcasses using an indocyanine green (ICG) fluorescent lymphography and a radiographic microinjection technique. Two live dogs were then subjected to unilateral lymph node dissection of lymph basins of the forelimb, and ICG lymphography and lymphangiogram were performed 6 months after the surgery to investigate lymphatic changes. Lymphatic patterns in the carcass were then compared with postoperative lymphatic patterns in the live dogs. Results Ten lymphosomes were identified, corresponding with ten lymphatic basins. Postoperative fluorescent lymphographic images and lymphangiograms in the live dogs revealed small caliber lymphatic network fulfilling gaps in the surgical area and collateral lymphatic vessels arising from the network connecting to lymph nodes in the contralateral and ipsilateral neck in one dog and the ipsilateral subclavicular vein in another dog. Conclusion Our canine lymphosome map allowed us to observe lymphatic collateral formations after lymph node dissection in live dogs. This canine model may help clarify our understanding of postoperative lymphatic changes in humans in future studies. PMID:23894435

  7. The Lymphatic Immune Response Induced by the Adjuvant AS01: A Comparison of Intramuscular and Subcutaneous Immunization Routes.

    PubMed

    Neeland, Melanie R; Shi, Wei; Collignon, Catherine; Taubenheim, Nadine; Meeusen, Els N T; Didierlaurent, Arnaud M; de Veer, Michael J

    2016-10-01

    The liposome-based adjuvant AS01 incorporates two immune stimulants, 3-O-desacyl-4'-monophosphoryl lipid A and the saponin QS-21. AS01 is under investigation for use in several vaccines in clinical development. i.m. injection of AS01 enhances immune cell activation and dendritic cell (DC) Ag presentation in the local muscle-draining lymph node. However, cellular and Ag trafficking in the lymphatic vessels that connect an i.m. injection site with the local lymph node has not been investigated. The objectives of this study were: 1) to quantify the in vivo cellular immune response induced by AS01 in an outbred ovine model, 2) to develop a lymphatic cannulation model that directly collects lymphatic fluid draining the muscle, and 3) to investigate the function of immune cells entering and exiting the lymphatic compartments after s.c. or i.m. vaccination with AS01 administered with hepatitis B surface Ag (HBsAg). We show that HBsAg-AS01 induces a distinct immunogenic cellular signature within the blood and draining lymphatics following both immunization routes. We reveal that MHCII(high) migratory DCs, neutrophils, and monocytes can acquire Ag within muscle and s.c. afferent lymph, and that HBsAg-AS01 uniquely induces the selective migration of Ag-positive neutrophils, monocytes, and an MHCII(high) DC-like cell type out of the lymph node via the efferent lymphatics that may enhance Ag-specific immunity. We report the characterization of the immune response in the lymphatic network after i.m. and s.c. injection of a clinically relevant vaccine, all in real time using a dose and volume comparable with that administered in humans. PMID:27549170

  8. Efficient Assessment of Developmental, Surgical and Pathological Lymphangiogenesis Using a Lymphatic Reporter Mouse and Its Embryonic Stem Cells

    PubMed Central

    Jung, Wonhyuek; Seong, Young Jin; Park, Eunkyung; Bramos, Athanasios; Kim, Kyu Eui; Lee, Sunju; Daghlian, George; Seo, Jung In; Choi, Inho; Choi, In-Seon; Koh, Chester J.; Kobielak, Agnieszka; Ying, Qi-Long; Johnson, Maxwell; Gardner, Daniel; Wong, Alex K.; Choi, Dongwon; Hong, Young-Kwon

    2016-01-01

    Several lymphatic reporter mouse lines have recently been developed to significantly improve imaging of lymphatic vessels. Nonetheless, the usage of direct visualization of lymphatic vessels has not been fully explored and documented. Here, we characterized a new Prox1-tdTomato transgenic lymphatic reporter mouse line, and demonstrated how this animal tool enables the researchers to efficiently assess developmental, surgical and pathological lymphangiogenesis by direct visualization of lymphatic vessels. Moreover, we have derived embryonic stem cells from this reporter line, and successfully differentiated them into lymphatic vessels in vivo. In conclusion, these experimental tools and techniques will help advance lymphatic research. PMID:27280889

  9. The Lymphatic System in Disease Processes and Cancer Progression.

    PubMed

    Padera, Timothy P; Meijer, Eelco F J; Munn, Lance L

    2016-07-11

    Advances in our understanding of the structure and function of the lymphatic system have made it possible to identify its role in a variety of disease processes. Because it is involved not only in fluid homeostasis but also in immune cell trafficking, the lymphatic system can mediate and ultimately alter immune responses. Our rapidly increasing knowledge of the molecular control of the lymphatic system will inevitably lead to new and effective therapies for patients with lymphatic dysfunction. In this review, we discuss the molecular and physiological control of lymphatic vessel function and explore how the lymphatic system contributes to many disease processes, including cancer and lymphedema.

  10. Clinical Significance and Role of Lymphatic Vessel Invasion as a Major Prognostic Implication in Non-Small Cell Lung Cancer: A Meta-Analysis

    PubMed Central

    Zhao, Weipeng; Guo, Yan; Chen, Hong; Chu, Huili; Liang, Xiuju; Bi, Jingwang

    2012-01-01

    Background Lymphatic vessel invasion (LVI) exerts an important process in the progression and local spread of cancer cells. However, LVI as a prognostic factor for survival in non-small cell lung cancer (NSCLC) remains controversial. Methodology/Principal Findings A meta-analysis of published studies from PubMed and EMBASE electronic databases was performed to quantity the effects of LVI on both relapse-free survival and overall survival for patients with NSCLC. Hazard ratios (HRs) with 95% confidence intervals (95% CIs) were used to assess the strength of these effects. This meta-analysis included 18,442 NSCLC patients from 53 eligible studies. LVI appeared in 32.1% (median; range, 2.8% to 70.9%) of tumor samples. In all, patients with LVI were 2.48 times more likely to relapse by univariate analysis (95% CI: 1.92–3.22) and 1.73 times by multivariate analysis (95% CI: 1.24–2.41) compared with those without LVI. For the analyses of LVI and overall survival, the pooled HR estimate was 1.97 (95% CI: 1.75–2.21) by univariate analysis and 1.59 (95% CI: 1.41–1.79) by multivariate analysis. Multivariate analysis showed a risk was 91% higher for recurrence (HR  = 1.91, 95% CI: 1.14–2.91) and 70% higher for mortality (HR = 1.70, 95% CI: 1.38–2.10) in LVI-positive I stage patients compared with LVI-negative I stage patients. Subgroup analyses showed similar significant adjusted risks for recurrence and death in adenocarcinomas, and a significant adjusted risk for death in studies that utilized elastic staining with or without immunohistochemistry in defining LVI. Conclusions/Significance The present study indicates that LVI appears to be an independent poor prognosticator in surgically managed NSCLC. NSCLC patients with LVI would require a more aggressive treatment strategy after surgery. However, large, well-designed prospective studies with clinically relevant modeling and standard methodology to assess LVI are required to address some of these

  11. Lymphatic Imaging: Focus on Imaging Probes

    PubMed Central

    Niu, Gang; Chen, Xiaoyuan

    2015-01-01

    In view of the importance of sentinel lymph nodes (SLNs) in tumor staging and patient management, sensitive and accurate imaging of SLNs has been intensively explored. Along with the advance of the imaging technology, various contrast agents have been developed for lymphatic imaging. In this review, the lymph node imaging agents were summarized into three groups: tumor targeting agents, lymphatic targeting agents and lymphatic mapping agents. Tumor targeting agents are used to detect metastatic tumor tissue within LNs, lymphatic targeting agents aim to visualize lymphatic vessels and lymphangionesis, while lymphatic mapping agents are mainly for SLN detection during surgery after local administration. Coupled with various signal emitters, these imaging agents work with single or multiple imaging modalities to provide a valuable way to evaluate the location and metastatic status of SLNs. PMID:25897334

  12. Lymphatic regulation in nonmammalian vertebrates.

    PubMed

    Hedrick, Michael S; Hillman, Stanley S; Drewes, Robert C; Withers, Philip C

    2013-08-01

    All vertebrate animals share in common the production of lymph through net capillary filtration from their closed circulatory system into their tissues. The balance of forces responsible for net capillary filtration and lymph formation is described by the Starling equation, but additional factors such as vascular and interstitial compliance, which vary markedly among vertebrates, also have a significant impact on rates of lymph formation. Why vertebrates show extreme variability in rates of lymph formation and how nonmammalian vertebrates maintain plasma volume homeostasis is unclear. This gap hampers our understanding of the evolution of the lymphatic system and its interaction with the cardiovascular system. The evolutionary origin of the vertebrate lymphatic system is not clear, but recent advances suggest common developmental factors for lymphangiogenesis in teleost fishes, amphibians, and mammals with some significant changes in the water-land transition. The lymphatic system of anuran amphibians is characterized by large lymphatic sacs and two pairs of lymph hearts that return lymph into the venous circulation but no lymph vessels per se. The lymphatic systems of reptiles and some birds have lymph hearts, and both groups have extensive lymph vessels, but their functional role in both lymph movement and plasma volume homeostasis is almost completely unknown. The purpose of this review is to present an evolutionary perspective in how different vertebrates have solved the common problem of the inevitable formation of lymph from their closed circulatory systems and to point out the many gaps in our knowledge of this evolutionary progression.

  13. Lymphatic regulation in nonmammalian vertebrates.

    PubMed

    Hedrick, Michael S; Hillman, Stanley S; Drewes, Robert C; Withers, Philip C

    2013-08-01

    All vertebrate animals share in common the production of lymph through net capillary filtration from their closed circulatory system into their tissues. The balance of forces responsible for net capillary filtration and lymph formation is described by the Starling equation, but additional factors such as vascular and interstitial compliance, which vary markedly among vertebrates, also have a significant impact on rates of lymph formation. Why vertebrates show extreme variability in rates of lymph formation and how nonmammalian vertebrates maintain plasma volume homeostasis is unclear. This gap hampers our understanding of the evolution of the lymphatic system and its interaction with the cardiovascular system. The evolutionary origin of the vertebrate lymphatic system is not clear, but recent advances suggest common developmental factors for lymphangiogenesis in teleost fishes, amphibians, and mammals with some significant changes in the water-land transition. The lymphatic system of anuran amphibians is characterized by large lymphatic sacs and two pairs of lymph hearts that return lymph into the venous circulation but no lymph vessels per se. The lymphatic systems of reptiles and some birds have lymph hearts, and both groups have extensive lymph vessels, but their functional role in both lymph movement and plasma volume homeostasis is almost completely unknown. The purpose of this review is to present an evolutionary perspective in how different vertebrates have solved the common problem of the inevitable formation of lymph from their closed circulatory systems and to point out the many gaps in our knowledge of this evolutionary progression. PMID:23640588

  14. A study of the three-dimensional organization of the human diaphragmatic lymphatic lacunae and lymphatic drainage units.

    PubMed

    Li, J; Zhao, Z; Zhou, J; Yu, S

    1996-12-01

    The peritoneal stomata, lymphatic drainage units and subperitoneal terminal lymphatics, called lymphatic lacunae, form a specialized drainage system in the diaphragm, by which absorption of fluid in bulk, particles and cells is carried out in the peritoneal cavity. The aim of this study is to elucidate the three-dimensional organization and function of the subperitoneal lymphatic lacunae and lymphatic drainage units by using lymphatic casts in the scanning electron microscope (SEM), ODO (OsO4-DMSO-OsO4) freeze fracture, conventional SEM and the transmission electron microscope (TEM). The subperitoneal lymphatic lacuna is unique for its large size and its multiple morphology and can be recognized by its broad, flattened enlargement and the blind-ends of lymphatic vessels, from which extend numerous main lymphatic vessels and side branches. These lymphatic vessels communicate with each other and form a rich lymphatic plexus under the diaphragmatic peritoneum. Two layers of lymphatic networks, i.e. the subperitoneal plexus and the deeper plexus are found in the muscular portion. Only one layer is present in the tendinous portion of the human diaphragm. The lymphatic plexus is denser in the tendinous portion than that in the muscular portion. The lymphatic lacunae occur exclusively in the muscular portion of the human diaphragm. The lumina of lymphatic lacunae are separated from the peritoneal cavity by a barrier consisting of cuboidal mesothelial cells, endothelial cells of the lymphatic lacunae and intervening connective tissue forming a lymphatic drainage unit. All these three components of the lymphatic drainage unit abut upon each other, but are not linked by specialized junctions. The cuboidal mesothelial cells frequently extend valve-like cytoplasmic processes that bridge the subperitoneal channel and make give it a tortuous course. The fibrous layer of the connective tissue is arranged in fiber bundles and gives a three-dimensional network forming the floor of

  15. The lymphatic vasculature: development and role in shaping immunity.

    PubMed

    Betterman, Kelly L; Harvey, Natasha L

    2016-05-01

    The lymphatic vasculature is an integral component of the immune system. Lymphatic vessels are a key highway via which immune cells are trafficked, serving not simply as a passive route of transport, but to actively shape and coordinate immune responses. Reciprocally, immune cells provide signals that impact the growth, development, and activity of the lymphatic vasculature. In addition to immune cell trafficking, lymphatic vessels are crucial for fluid homeostasis and lipid absorption. The field of lymphatic vascular research is rapidly expanding, fuelled by rapidly advancing technology that has enabled the manipulation and imaging of lymphatic vessels, together with an increasing recognition of the involvement of lymphatic vessels in a myriad of human pathologies. In this review we provide an overview of the genetic pathways and cellular processes important for development and maturation of the lymphatic vasculature, discuss recent work revealing important roles for the lymphatic vasculature in directing immune cell traffic and coordinating immune responses and highlight the involvement of lymphatic vessels in a range of pathological settings.

  16. The lymphatic vasculature: development and role in shaping immunity.

    PubMed

    Betterman, Kelly L; Harvey, Natasha L

    2016-05-01

    The lymphatic vasculature is an integral component of the immune system. Lymphatic vessels are a key highway via which immune cells are trafficked, serving not simply as a passive route of transport, but to actively shape and coordinate immune responses. Reciprocally, immune cells provide signals that impact the growth, development, and activity of the lymphatic vasculature. In addition to immune cell trafficking, lymphatic vessels are crucial for fluid homeostasis and lipid absorption. The field of lymphatic vascular research is rapidly expanding, fuelled by rapidly advancing technology that has enabled the manipulation and imaging of lymphatic vessels, together with an increasing recognition of the involvement of lymphatic vessels in a myriad of human pathologies. In this review we provide an overview of the genetic pathways and cellular processes important for development and maturation of the lymphatic vasculature, discuss recent work revealing important roles for the lymphatic vasculature in directing immune cell traffic and coordinating immune responses and highlight the involvement of lymphatic vessels in a range of pathological settings. PMID:27088921

  17. Clinical Feasibility of Noninvasive Visualization of Lymphatic Flow using Principles of Spin Labeling MRI: Implications for Lymphedema Assessment

    PubMed Central

    Rane, Swati; Donahue, Paula M. C.; Towse, Ted; Ridner, Sheila; Chappell, Michael; Jordi, John; Gore, John; Donahue, Manus J.

    2015-01-01

    Purpose To extend a commonly employed, noninvasive arterial spin labeling (ASL) MRI method for measuring blood flow to evaluate lymphatic flow. Materials and Methods All volunteers (n=12) provided informed consent in accordance with IRB and HIPAA regulations. Quantitative relaxation time (T1 and T2) measurements were made in extracted human lymphatic fluid at 3.0T. Guided by these parameters, an ASL MRI approach was adapted to measure lymphatic flow (flow-alternating-inversion-recovery lymphatic water labeling; 3×3×5 mm3) in healthy subjects (n=6; 30±1 yrs; recruitment duration=2 months). Lymphatic flow velocity was quantified by performing spin labeling measurements as a function of post-labeling delay time and measuring the time-to-peak of signal in axillary lymph nodes. Clinical feasibility was evaluated in Stage II lymphedema patients (n=3; 60yr/F, 43yr/F, 64yr/F) and control subjects with unilateral cuff-induced lymphatic stenosis (n=3; 31yr/M, 31yr/M, 35yr/F). Results T1 and T2 of lymphatic fluid at 3.0T were 3100±160 ms (range=2930-3210 ms; median=3200 ms) and 610±12 ms (range=598-618 ms; median=610 ms), respectively. Healthy lymphatic flow (afferent vessel to axillary node) velocity was found to be 0.61±0.13 cm/min (n=6). A reduction (P<0.005) in lymphatic flow velocity in the affected arms of patients and the affected arms of healthy subjects with manipulated cuff-induced flow reduction was observed. The ratio of unaffected to affected axilla lymphatic velocity (1.24±0.18) was significantly (P<0.005) higher than the Left/Right ratio in healthy subjects (0.91±0.18). Conclusion This work provides a foundation for clinical investigations whereby lymphedema etiogenesis and therapies may be interrogated without exogenous agents and with clinically available imaging equipment. PMID:23864103

  18. Antiedema effects of Siberian ginseng in humans and its molecular mechanism of lymphatic vascular function in vitro.

    PubMed

    Fukada, Kaedeko; Kajiya-Sawane, Mika; Matsumoto, Yuko; Hasegawa, Tatsuya; Fukaya, Yukitaka; Kajiya, Kentaro

    2016-07-01

    The lymphatic system in the skin plays a major role in tissue fluid homeostasis, in the afferent phase of the immune response, and in tumor metastasis. Although lymphangiogenic factors involved in embryonic development and the metastatic spread of tumor cells have been well studied, little is known about small-molecule compounds that activate lymphatic function, especially under physiological conditions. We hypothesized that the identification of a lymphatic-activating compound could provide a method for improving edema. Here, we show that Siberian ginseng (Eleutherococcus senticosus) and its component eleutheroside E induce phosphorylation of the endothelial-specific receptor Tie2 in vitro. The activation of Tie2 on lymphatic endothelial cells (LECs) is known to stabilize lymphatic vessels, so we examined the effects of Siberian ginseng on LECs. We found that Siberian ginseng induces the migration and cord formation of LECs. Permeability assays demonstrated that it stabilizes LECs by promoting the intercellular localization of vascular endothelial cadherin, which is an endothelium-specific cell-cell adhesion molecule involved in endothelial barrier function, and it induces the phosphorylation of endothelial nitric oxide synthase by LECs. These effects appear to be mediated by the activation of Tie2 in LECs. Finally, we investigated whether the consumption of Siberian ginseng powder improves edema in a 2-way, randomized, crossover study in 50 healthy female volunteers. Edema of the lower limbs was significantly attenuated at 2 and 4hours after ingestion as compared with the control group. Thus, we demonstrate that Siberian ginseng exerts its potent antiedema activity mainly by promoting lymphatic function. PMID:27333960

  19. Lymphatic Anomalies Registry

    ClinicalTrials.gov

    2016-07-26

    Lymphatic Malformation; Generalized Lymphatic Anomaly (GLA); Central Conducting Lymphatic Anomaly; CLOVES Syndrome; Gorham-Stout Disease ("Disappearing Bone Disease"); Blue Rubber Bleb Nevus Syndrome; Kaposiform Lymphangiomatosis; Kaposiform Hemangioendothelioma/Tufted Angioma; Klippel-Trenaunay Syndrome; Lymphangiomatosis

  20. Mechanotransduction activates canonical Wnt/β-catenin signaling to promote lymphatic vascular patterning and the development of lymphatic and lymphovenous valves.

    PubMed

    Cha, Boksik; Geng, Xin; Mahamud, Md Riaj; Fu, Jianxin; Mukherjee, Anish; Kim, Yeunhee; Jho, Eek-Hoon; Kim, Tae Hoon; Kahn, Mark L; Xia, Lijun; Dixon, J Brandon; Chen, Hong; Srinivasan, R Sathish

    2016-06-15

    Lymphatic vasculature regulates fluid homeostasis by returning interstitial fluid to blood circulation. Lymphatic endothelial cells (LECs) are the building blocks of the entire lymphatic vasculature. LECs originate as a homogeneous population of cells predominantly from the embryonic veins and undergo stepwise morphogenesis to become the lymphatic capillaries, collecting vessels or valves. The molecular mechanisms underlying the morphogenesis of the lymphatic vasculature remain to be fully understood. Here we show that canonical Wnt/β-catenin signaling is necessary for lymphatic vascular morphogenesis. Lymphatic vascular-specific ablation of β-catenin in mice prevents the formation of lymphatic and lymphovenous valves. Additionally, lymphatic vessel patterning is defective in these mice, with abnormal recruitment of mural cells. We found that oscillatory shear stress (OSS), which promotes lymphatic vessel maturation, triggers Wnt/β-catenin signaling in LECs. In turn, Wnt/β-catenin signaling controls the expression of several molecules, including the lymphedema-associated transcription factor FOXC2. Importantly, FOXC2 completely rescues the lymphatic vessel patterning defects in mice lacking β-catenin. Thus, our work reveals that mechanical stimulation is a critical regulator of lymphatic vascular development via activation of Wnt/β-catenin signaling and, in turn, FOXC2.

  1. Mechanotransduction activates canonical Wnt/β-catenin signaling to promote lymphatic vascular patterning and the development of lymphatic and lymphovenous valves

    PubMed Central

    Cha, Boksik; Geng, Xin; Mahamud, Md. Riaj; Fu, Jianxin; Mukherjee, Anish; Kim, Yeunhee; Jho, Eek-hoon; Kim, Tae Hoon; Kahn, Mark L.; Xia, Lijun; Dixon, J. Brandon; Chen, Hong; Srinivasan, R. Sathish

    2016-01-01

    Lymphatic vasculature regulates fluid homeostasis by returning interstitial fluid to blood circulation. Lymphatic endothelial cells (LECs) are the building blocks of the entire lymphatic vasculature. LECs originate as a homogeneous population of cells predominantly from the embryonic veins and undergo stepwise morphogenesis to become the lymphatic capillaries, collecting vessels or valves. The molecular mechanisms underlying the morphogenesis of the lymphatic vasculature remain to be fully understood. Here we show that canonical Wnt/β-catenin signaling is necessary for lymphatic vascular morphogenesis. Lymphatic vascular-specific ablation of β-catenin in mice prevents the formation of lymphatic and lymphovenous valves. Additionally, lymphatic vessel patterning is defective in these mice, with abnormal recruitment of mural cells. We found that oscillatory shear stress (OSS), which promotes lymphatic vessel maturation, triggers Wnt/β-catenin signaling in LECs. In turn, Wnt/β-catenin signaling controls the expression of several molecules, including the lymphedema-associated transcription factor FOXC2. Importantly, FOXC2 completely rescues the lymphatic vessel patterning defects in mice lacking β-catenin. Thus, our work reveals that mechanical stimulation is a critical regulator of lymphatic vascular development via activation of Wnt/β-catenin signaling and, in turn, FOXC2. PMID:27313318

  2. Improved computer-assisted analysis of the global lymphatic network in human cervical tissues.

    PubMed

    Balsat, Cédric; Signolle, Nicolas; Goffin, Frédéric; Delbecque, Katty; Plancoulaine, Benoit; Sauthier, Philippe; Samouëlian, Vanessa; Béliard, Aude; Munaut, Carine; Foidart, Jean-Michel; Blacher, Silvia; Noël, Agnès; Kridelka, Frédéric

    2014-06-01

    Lymphatic dissemination is a key event in cervical cancer progression and related tumor lymphatic markers are viewed as promising prognostic factor of nodal extension. However, validating such parameters requires an objective characterization of the lymphatic vasculature. Here, we performed a global analysis of the lymphatic network using a new computerized method applied on whole uterine cervical digital images. Sixty-eight cases of cervical neoplasia (12 CIN3, 10 FIGO stage 1A and 46 stage IB1) and 10 cases of normal cervical tissue were reacted with antibodies raised against D2-40, D2-40/p16 and D2-40/Ki67. Immunostained structures were automatically detected on whole slides. The lymphatic vessel density (D2-40), proliferating lymphatic vessel density (D2-40/ki67) and spatial lymphatic distribution in respect to the adjacent epithelium were assessed from normal cervix to early cervical cancer and correlated with lymphovascular space invasion and lymph node status. Prominent lymphatic vessel density and proliferating lymphatic vessel density are detected under the transformation zone of benign cervix and no further increase is noted during cancer progression. Notably, a shift of lymphatic vessel distribution toward the neoplastic edges is detected. In IB1 cervical cancer, although intra- and peritumoral lymphatic vessel density are neither correlated with lymphovascular space invasion nor with lymph node metastasis, a specific spatial distribution with more lymphatic vessels in the vicinity of tumor edges is predictive of lymphatic dissemination. Herein, we provide a new computerized method suitable for an innovative detailed analysis of the lymphatic network. We show that the transformation zone of the benign cervix acts as a baseline lymphangiogenic niche before the initiation of neoplastic process. During cancer progression, this specific microenvironment is maintained with lymphatic vessels even in closer vicinity to tumor cells. PMID:24309324

  3. Heterogeneity in the lymphatic vascular system and its origin.

    PubMed

    Ulvmar, Maria H; Mäkinen, Taija

    2016-09-01

    Lymphatic vessels have historically been viewed as passive conduits for fluid and immune cells, but this perspective is increasingly being revised as new functions of lymphatic vessels are revealed. Emerging evidence shows that lymphatic endothelium takes an active part in immune regulation both by antigen presentation and expression of immunomodulatory genes. In addition, lymphatic vessels play an important role in uptake of dietary fat and clearance of cholesterol from peripheral tissues, and they have been implicated in obesity and arteriosclerosis. Lymphatic vessels within different organs and in different physiological and pathological processes show a remarkable plasticity and heterogeneity, reflecting their functional specialization. In addition, lymphatic endothelial cells (LECs) of different organs were recently shown to have alternative developmental origins, which may contribute to the development of the diverse lymphatic vessel and endothelial functions seen in the adult. Here, we discuss recent developments in the understanding of heterogeneity within the lymphatic system considering the organ-specific functional and molecular specialization of LECs and their developmental origin. PMID:27357637

  4. Heterogeneity in the lymphatic vascular system and its origin.

    PubMed

    Ulvmar, Maria H; Mäkinen, Taija

    2016-09-01

    Lymphatic vessels have historically been viewed as passive conduits for fluid and immune cells, but this perspective is increasingly being revised as new functions of lymphatic vessels are revealed. Emerging evidence shows that lymphatic endothelium takes an active part in immune regulation both by antigen presentation and expression of immunomodulatory genes. In addition, lymphatic vessels play an important role in uptake of dietary fat and clearance of cholesterol from peripheral tissues, and they have been implicated in obesity and arteriosclerosis. Lymphatic vessels within different organs and in different physiological and pathological processes show a remarkable plasticity and heterogeneity, reflecting their functional specialization. In addition, lymphatic endothelial cells (LECs) of different organs were recently shown to have alternative developmental origins, which may contribute to the development of the diverse lymphatic vessel and endothelial functions seen in the adult. Here, we discuss recent developments in the understanding of heterogeneity within the lymphatic system considering the organ-specific functional and molecular specialization of LECs and their developmental origin.

  5. Heterogeneity in the lymphatic vascular system and its origin

    PubMed Central

    Ulvmar, Maria H.; Mäkinen, Taija

    2016-01-01

    Lymphatic vessels have historically been viewed as passive conduits for fluid and immune cells, but this perspective is increasingly being revised as new functions of lymphatic vessels are revealed. Emerging evidence shows that lymphatic endothelium takes an active part in immune regulation both by antigen presentation and expression of immunomodulatory genes. In addition, lymphatic vessels play an important role in uptake of dietary fat and clearance of cholesterol from peripheral tissues, and they have been implicated in obesity and arteriosclerosis. Lymphatic vessels within different organs and in different physiological and pathological processes show a remarkable plasticity and heterogeneity, reflecting their functional specialization. In addition, lymphatic endothelial cells (LECs) of different organs were recently shown to have alternative developmental origins, which may contribute to the development of the diverse lymphatic vessel and endothelial functions seen in the adult. Here, we discuss recent developments in the understanding of heterogeneity within the lymphatic system considering the organ-specific functional and molecular specialization of LECs and their developmental origin. PMID:27357637

  6. Demonstrating the lymphatic system in rats with microinjection.

    PubMed

    Suami, Hiroo; Chang, David W; Matsumoto, Kumiko; Kimata, Yoshihiro

    2011-09-01

    The lymphatic system plays an important role in human health and disease. In addition to a role in the immune response, the lymphatics can serve as a pathway for cancer metastasis. Visualizing the lymphatic system has been a difficult part of anatomic dissection studies. Anatomists have attempted to map the lymphatic system using various methods and materials; vivisection of dogs, injection of mercury into the skin and lymphatic vessel in cadavers, and injection of dye indirectly into the skin of dead and living specimens. In this study, we introduce a method of using a mixture of acrylic blue dye and hydrogen peroxide to visualize the lymphatic system in rats. The lymphatic vessels were cannulated with micropipettes, and radio-opaque orange lead oxide was selectively injected. The lymphatic system became visible from the dorsal side of the hand and foot, and distal region of the tail to their termination at the left and right subclavicular veins via lymph nodes. Cisterna chyli in the abdominal cavity and thoracic duct ran along with the aorta. The advantage of this technique is that lymph nodes as well as lymphatic channels could be recorded not only photographically but also radiographically. This microinjection technique is useful for demonstrating the lymphatic system in rats and may provide further information that will help in cancer metastasis research.

  7. Imaging the lymphatic system.

    PubMed

    Munn, Lance L; Padera, Timothy P

    2014-11-01

    Visualization of the lymphatic system is clinically necessary during diagnosis or treatment of many conditions and diseases; it is used for identifying and monitoring lymphedema, for detecting metastatic lesions during cancer staging and for locating lymphatic structures so they can be spared during surgical procedures. Imaging lymphatic anatomy and function also plays an important role in experimental studies of lymphatic development and function, where spatial resolution and accessibility are better. Here, we review technologies for visualizing and imaging the lymphatic system for clinical applications. We then describe the use of lymphatic imaging in experimental systems as well as some of the emerging technologies for improving these methodologies.

  8. Imaging the lymphatic system

    PubMed Central

    Munn, Lance L.; Padera, Timothy P.

    2014-01-01

    Visualization of the lymphatic system is clinically necessary during diagnosis or treatment of many conditions and diseases; it is used for identifying and monitoring lymphedema, for detecting metastatic lesions during cancer staging and for locating lymphatic structures so they can be spared during surgical procedures. Imaging lymphatic anatomy and function also plays an important role in experimental studies of lymphatic development and function, where spatial resolution and accessibility are better. Here, we review technologies for visualizing and imaging the lymphatic system for clinical applications. We then describe the use of lymphatic imaging in experimental systems as well as some of the emerging technologies for improving these methodologies. PMID:24956510

  9. Immunopathogenesis of lymphatic filarial disease.

    PubMed

    Babu, Subash; Nutman, Thomas B

    2012-11-01

    Although two thirds of the 120 million people infected with lymph-dwelling filarial parasites have subclinical infections, ~40 million have lymphedema and/or other pathologic manifestations including hydroceles (and other forms of urogenital disease), episodic adenolymphangitis, tropical pulmonary eosinophilia, lymphedema, and (in its most severe form) elephantiasis. Adult filarial worms reside in the lymphatics and lymph nodes and induce changes that result in dilatation of lymphatics and thickening of the lymphatic vessel walls. Progressive lymphatic damage and pathology results from the summation of the effect of tissue alterations induced by both living and nonliving adult parasites, the host inflammatory response to the parasites and their secreted antigens, the host inflammatory response to the endosymbiont Wolbachia, and those seen as a consequence of secondary bacterial or fungal infections. Inflammatory damage induced by filarial parasites appears to be multifactorial, with endogenous parasite products, Wolbachia, and host immunity all playing important roles. This review will initially examine the prototypical immune responses engendered by the parasite and delineate the regulatory mechanisms elicited to prevent immune-mediated pathology. This will be followed by a discussion of the proposed mechanisms underlying pathogenesis, with the central theme being that pathogenesis is a two-step process-the first initiated by the parasite and host innate immune system and the second propagated mainly by the host's adaptive immune system and by other factors (including secondary infections). PMID:23053393

  10. Tissue contribution to the mechanical features of diaphragmatic initial lymphatics

    PubMed Central

    Moriondo, Andrea; Boschetti, Federica; Bianchin, Francesca; Lattanzio, Simone; Marcozzi, Cristiana; Negrini, Daniela

    2010-01-01

    The role of the mechanical properties of the initial lymphatic wall and of the surrounding tissue in supporting lymph formation and/or progression was studied in six anaesthetized, neuromuscularly blocked and mechanically ventilated rats. After mid-sternal thoracotomy, submesothelial initial lymphatics were identified on the pleural diaphragmatic surface through stereomicroscopy. An ‘in vivo’ lymphatic segment was prepared by securing two surgical threads around the vessel at a distance of ∼2.5 mm leaving the vessel in place. Two glass micropipettes were inserted into the lumen, one for intraluminar injections of 4.6 nl saline boluses and one for hydraulic pressure (Plymph) recording. The compliance of the vessel wall (Clymph) was calculated as the slope of the plot describing the change in segment volume as a function of the post-injection Plymph changes. Two superficial lymphatic vessel populations with a significantly different Clymph (6.7 ± 1.6 and 1.5 ± 0.4 nl mmHg−1 (mean ± s.e.m.), P < 0.001) were identified. In seven additional rats, the average elastic modulus of diaphragmatic tissue strips was determined by uniaxial tension tests to be 1.7 ± 0.3 MPa. Clymph calculated for an initial lymphatic completely surrounded by isotropic tissue was 0.068 nl mmHg−1, i.e. two orders of magnitude lower than in submesothelial lymphatics. Modelling of stress distribution in the lymphatic wall suggests that compliant vessels may act as reservoirs accommodating large absorbed fluid volumes, while lymphatics with stiffer walls serve to propel fluid through the lumen of the lymphatic vessel by taking advantage of the more efficient mechanical transmission of tissue stresses to the lymphatic lumen. PMID:20724369

  11. A New Technique to Map the Lymphatic Distribution and Alignment of the Penis.

    PubMed

    Long, Liu Yan; Qiang, Pan Fu; Ling, Tao; Wei, Zhang Yan; Long, Zhang Yu; Shan, Meng; Rong, Li Shi; Li, Li Hong

    2015-08-01

    The present study was to examine the distribution of lymphatic vessels in the penis of normal adult males, which could provide an anatomical basis for improvement of incisions in penile lengthening surgery, and may also help to prevent postoperative refractory edema. Thirteen normal adult male volunteers were recruited for this study. Contrast agent was injected subcutaneously in the foreskin of the penis, and after two minutes magnetic resonance lymphangiography (MRL) was performed. The acquired magnetic resonance images were analyzed to determine the changes in the number and diameter of lymphatic vessels in different parts of the penis. Maximum intensity projections (MIP) and materializes interactive medical image control system (MIMICS) were applied to analyze the overall distribution of lymphatic vessels in the penis. Magnetic resonance imaging (MRI) showed that the lymphatic vessels were in conspicuous contrast with surrounding tissues and could be clearly identified. Penile lymphatic vessels were clearly visible in the root of the penis. At the junction of the penis and the abdominal wall, all lymphatic vessels were found to be concentrated in the dorsal part of the penis. MIP two-dimensional reconstruction showed that the overall distribution of relatively large lymphatic vessels in the dorsal and ventral parts of the penis could be seen clearly on bilateral 45° position, but not inside the abdominal wall because some of lymphatic vessels were overlapped by other tissues in the abdomen. MIMICS three-dimensional reconstruction was able to reveal the overall spatial distribution of lymphatic vessels in the penis from any angle. The reconstruction results showed that there were 1-2 main lymphatic vessels on the root of dorsal penis, which coursed along the cavernous to the first physiological curvature of the penis. Lymphatic vessels merged on both sides of the ventral penis. At the root of the penis, lymphatic vessels gradually coursed to the dorsal surface

  12. Lymphatic communication: Connexin junction, what’s your function?

    PubMed Central

    Kanady, John D.; Simon, Alexander M.

    2012-01-01

    Summary This article reviews recent findings on expression and function of connexin proteins - the structural subunits of gap junction intercellular channels in the lymphatic vasculature - both during development and in the mature lymphatic vessel. Highlighted in particular are recent mouse connexin knockout studies which show that connexins are crucial for normal lymphatic development. We discuss, in general terms, both channel-dependent as well as channel-independent functions of connexins and raise some of the many unanswered questions about the mechanism(s) of action and physiological roles of connexins in the lymphatic vasculature. PMID:22165579

  13. Anatomy and development of the cardiac lymphatic vasculature: Its role in injury and disease.

    PubMed

    Norman, Sophie; Riley, Paul R

    2016-04-01

    Lymphatic vessels are present throughout the entire body in all mammals and function to regulate tissue fluid balance, lipid transport and survey the immune system. Despite the presence of an extensive lymphatic plexus within the heart, until recently the importance of the cardiac lymphatic vasculature and its origins were unknown. Several studies have described the basic anatomy of the developing cardiac lymphatic vasculature and more recently the detailed development of the murine cardiac lymphatics has been documented, with important insight into their cellular sources during embryogenesis. In this review we initially describe the development of systemic lymphatic vasculature, to provide the background for a comparative description of the spatiotemporal development of the cardiac lymphatic vessels, including detail of both canonical, typically venous, and noncanonical (hemogenic endothelium) cellular sources. Subsequently, we address the response of the cardiac lymphatic network to myocardial infarction (heart attack) and the therapeutic potential of targeting cardiac lymphangiogenesis.

  14. Anatomy and development of the cardiac lymphatic vasculature: Its role in injury and disease.

    PubMed

    Norman, Sophie; Riley, Paul R

    2016-04-01

    Lymphatic vessels are present throughout the entire body in all mammals and function to regulate tissue fluid balance, lipid transport and survey the immune system. Despite the presence of an extensive lymphatic plexus within the heart, until recently the importance of the cardiac lymphatic vasculature and its origins were unknown. Several studies have described the basic anatomy of the developing cardiac lymphatic vasculature and more recently the detailed development of the murine cardiac lymphatics has been documented, with important insight into their cellular sources during embryogenesis. In this review we initially describe the development of systemic lymphatic vasculature, to provide the background for a comparative description of the spatiotemporal development of the cardiac lymphatic vessels, including detail of both canonical, typically venous, and noncanonical (hemogenic endothelium) cellular sources. Subsequently, we address the response of the cardiac lymphatic network to myocardial infarction (heart attack) and the therapeutic potential of targeting cardiac lymphangiogenesis. PMID:26443964

  15. Intestinal and peri-tumoral lymphatic endothelial cells are resistant to radiation-induced apoptosis

    SciTech Connect

    Sung, Hoon Ki; Morisada, Tohru; Cho, Chung-Hyun; Oike, Yuichi; Lee, Jayhun; Sung, Eon Ki; Chung, Jae Hoon; Suda, Toshio; Koh, Gou Young . E-mail: gykoh@kaist.ac.kr

    2006-06-30

    Radiation therapy is a widely used cancer treatment, but it is unable to completely block cancer metastasis. The lymphatic vasculature serves as the primary route for metastatic spread, but little is known about how lymphatic endothelial cells respond to radiation. Here, we show that lymphatic endothelial cells in the small intestine and peri-tumor areas are highly resistant to radiation injury, while blood vessel endothelial cells in the small intestine are relatively sensitive. Our results suggest the need for alternative therapeutic modalities that can block lymphatic endothelial cell survival, and thus disrupt the integrity of lymphatic vessels in peri-tumor areas.

  16. Communication between lymphatic and venous systems in mice.

    PubMed

    Shao, Lenan; Takeda, Kazu; Kato, Shigeki; Mori, Shiro; Kodama, Tetsuya

    2015-09-01

    The lymphatic system in mice consists of lymphatic vessels and 22 types of lymph nodes. Metastatic tumor cells in the lymphatic system spread to distant organs through the venous system. However, the communication routes between the lymphatic and venous systems have not been fully elucidated. Here, we identify the communication routes between the lymphatic and venous systems in the axillary and subiliac regions of MXH10/Mo-lpr/lpr inbred mice, which develop systemic swelling of lymph nodes up to 10mm in diameter, allowing investigation of the topography of the lymph nodes and lymphatic vessels. Using a gross anatomy dissection approach, the efferent lymphatic vessels of the proper axillary lymph node were shown to communicate with the subclavian vein. Furthermore, we found that the thoracoepigastric vein, which connects the subclavian vein and inferior vena cava, runs adjacent to the subiliac and proper axillary lymph nodes, and receives venous blood from these lymph nodes routed through small branches. The direction of blood flow in the thoracoepigastric vein occurred in two directions in the intermediate region between the proper axillary lymph node and subiliac lymph node; one to the subclavian vein, the other to the inferior vena cava. This paper reveals the anatomy of the communication between the lymphatic and venous systems in the axillary and subiliac regions of the mouse, and provides new insights relevant to the investigation of the mechanisms of lymph node metastasis and cancer immunology, and the development of diagnostic and treatment methods for lymph node metastasis, including drug delivery systems.

  17. Effects of LDL Receptor Modulation on Lymphatic Function

    PubMed Central

    Milasan, Andreea; Dallaire, François; Mayer, Gaétan; Martel, Catherine

    2016-01-01

    Atherosclerosis is driven by the accumulation of immune cells and cholesterol in the arterial wall. Although recent studies have shown that lymphatic vessels play an important role in macrophage reverse cholesterol transport, the specific underlying mechanisms of this physiological feature remain unknown. In the current report, we sought to better characterize the lymphatic dysfunction that is associated with atherosclerosis by studying the physiological and temporal origins of this impairment. First, we assessed that athero-protected Pcsk9−/− mice exhibited improved collecting lymphatic vessel function throughout age when compared to WT mice for up to six months, while displaying enhanced expression of LDLR on lymphatic endothelial cells. Lymphatic dysfunction was present before the atherosclerotic lesion formation in a mouse model that is predisposed to develop atherosclerosis (Ldlr−/−; hApoB100+/+). This dysfunction was presumably associated with a defect in the collecting lymphatic vessels in a non-specific cholesterol- but LDLR-dependent manner. Treatment with a selective VEGFR-3 agonist rescued this impairment observed early in the onset of this arterial disease. We suggest that LDLR modulation is associated with early atherosclerosis-related lymphatic dysfunction, and bring forth a pleiotropic role for PCSK9 in lymphatic function. Our study unveils new potential therapeutic targets for the prevention and treatment of atherosclerosis. PMID:27279328

  18. Pkd1 regulates lymphatic vascular morphogenesis during development

    PubMed Central

    Coxam, Baptiste; Sabine, Amélie; Bower, Neil I.; Smith, Kelly A.; Pichol-Thievend, Cathy; Skoczylas, Renae; Astin, Jonathan W.; Frampton, Emmanuelle; Jaquet, Muriel; Crosier, Philip S.; Parton, Robert G.; Harvey, Natasha L.; Petrova, Tatiana V.; Schulte-Merker, Stefan; Francois, Mathias; Hogan, Benjamin M.

    2016-01-01

    Lymphatic vessels arise during development through sprouting of precursor cells from veins, which is regulated by well-studied signaling and transcriptional mechanisms. Less well understood is the ongoing elaboration of vessels to form a network. This involves cell polarisation, coordinated migration, adhesion, mixing, regression and cell shape rearrangements. We identified a zebrafish mutant, lymphatic and cardiac defects 1 (lyc1), with reduced lymphatic vessel development. We found a mutation in polycystic kidney disease 1a to be responsible for the phenotype. PKD1 is the most frequently mutated gene in autosomal dominant polycystic kidney disease (ADPKD). Initial sprouting of lymphatic precursors is normal in lyc1 mutants, but ongoing migration fails. Loss of Pkd1 in mice also has no effect on sprouting of precursors but leads to failed morphogenesis of the subcutaneous lymphatic network. Individual lymphatic endothelial cells display defective polarity, elongation and adherens junctions. This work identifies a highly selective and unexpected role for Pkd1 in lymphatic vessel morphogenesis during development. PMID:24767999

  19. Platelets: Covert Regulators of Lymphatic Development

    PubMed Central

    Bertozzi, Cara C.; Hess, Paul R.; Kahn, Mark L.

    2010-01-01

    The field of platelet biology has rapidly expanded beyond the classical role of platelets in preventing blood loss and orchestrating clot formation. Despite the lack of transcriptional ability of these anuclear cell fragments, platelet function is now thought to encompass such diverse contexts as tissue repair, immune activation, primary tumor formation, and metastasis. Recent studies from multiple groups have turned the spotlight on an exciting new role for platelets in the formation of lymphatic vessels during embryonic development. Genetic experiments demonstrate that Podoplanin, a transmembrane protein expressed on lymphatic endothelial cells, engages the platelet CLEC-2 receptor when exposed to blood, leading to SYK-SLP-76-dependent platelet activation. When components of this pathway are disrupted, aberrant vascular connections form, resulting in blood-lymphatic mixing. Furthermore, platelet-null embryos manifest identical blood-lymphatic mixing. The identification of platelets as the critical cell type mediating blood-lymphatic vascular separation raises new questions in our understanding of lymphatic development and platelet biology. PMID:21071706

  20. Vascular endothelial growth factor receptor-2 promotes the development of the lymphatic vasculature.

    PubMed

    Dellinger, Michael T; Meadows, Stryder M; Wynne, Katherine; Cleaver, Ondine; Brekken, Rolf A

    2013-01-01

    Vascular endothelial growth factor receptor 2 (VEGFR2) is highly expressed by lymphatic endothelial cells and has been shown to stimulate lymphangiogenesis in adult mice. However, the role VEGFR2 serves in the development of the lymphatic vascular system has not been defined. Here we use the Cre-lox system to show that the proper development of the lymphatic vasculature requires VEGFR2 expression by lymphatic endothelium. We show that Lyve-1(wt/Cre);Vegfr2(flox/flox) mice possess significantly fewer dermal lymphatic vessels than Vegfr2(flox/flox) mice. Although Lyve-1(wt/Cre);Vegfr2(flox/flox) mice exhibit lymphatic hypoplasia, the lymphatic network is functional and contains all of the key features of a normal lymphatic network (initial lymphatic vessels and valved collecting vessels surrounded by smooth muscle cells (SMCs)). We also show that Lyve-1(Cre) mice display robust Cre activity in macrophages and in blood vessels in the yolk sac, liver and lung. This activity dramatically impairs the development of blood vessels in these tissues in Lyve-1(wt/Cre);Vegfr2(flox/flox) embryos, most of which die after embryonic day14.5. Lastly, we show that inactivation of Vegfr2 in the myeloid lineage does not affect the development of the lymphatic vasculature. Therefore, the abnormal lymphatic phenotype of Lyve-1(wt/Cre);Vegfr2(flox/flox) mice is due to the deletion of Vegfr2 in the lymphatic vasculature not macrophages. Together, this work demonstrates that VEGFR2 directly promotes the expansion of the lymphatic network and further defines the molecular mechanisms controlling the development of the lymphatic vascular system.

  1. A tale of two models: mouse and zebrafish as complementary models for lymphatic studies.

    PubMed

    Kim, Jun-Dae; Jin, Suk-Won

    2014-07-01

    Lymphatic vessels provide essential roles in maintaining fluid homeostasis and lipid absorption. Dysfunctions of the lymphatic vessels lead to debilitating pathological conditions, collectively known as lymphedema. In addition, lymphatic vessels are a critical moderator for the onset and progression of diverse human diseases including metastatic cancer and obesity. Despite their clinical importance, there is no currently effective pharmacological therapy to regulate functions of lymphatic vessels. Recent efforts to manipulate the Vascular Endothelial Growth Factor-C (VEGFC) pathway, which is arguably the most important signaling pathway regulating lymphatic endothelial cells, to alleviate lymphedema yielded largely mixed results, necessitating identification of new targetable signaling pathways for therapeutic intervention for lymphedema. Zebrafish, a relatively new model system to investigate lymphatic biology, appears to be an ideal model to identify novel therapeutic targets for lymphatic biology. In this review, we will provide an overview of our current understanding of the lymphatic vessels in vertebrates, and discuss zebrafish as a promising in vivo model to study lymphatic vessels.

  2. Rho Kinase Enhances Contractions of Rat Mesenteric Collecting Lymphatics

    PubMed Central

    Kurtz, Kristine H.; Souza-Smith, Flavia M.; Moor, Andrea N.; Breslin, Jerome W.

    2014-01-01

    The mechanisms that control phasic and tonic contractions of lymphatic vessels are poorly understood. We hypothesized that rho kinase ROCK, previously shown to increase calcium (Ca2+) sensitivity in vascular smooth muscle, enhances lymphatic contractile activity in a similar fashion. Contractions of isolated rat mesenteric lymphatic vessels were observed at a luminal pressure of 2 cm H2O in a 37°C bath. The expression of ROCK in isolated rat mesenteric lymphatic vessels was assessed by Western blotting and confocal microscopy. The role of ROCK in contractile function was tested using two specific yet structurally distinct inhibitors: H1152 (0.1–10 μM) and Y-27632 (0.5–50 μM). In addition, lymphatics were transfected with constitutively active (ca)-ROCK protein (2 μg/ml) to assess gain of contractile function. Vessel diameter and the concentration of intracellular free Ca2+ ([Ca2+]i) were simultaneously measured in a subset of isolated lymphatics loaded with the Ca2+-sensing dye fura-2. The results show expression of both the ROCK1 and ROCK2 isoforms in lymphatic vessels. Inhibition of ROCK increased lymphatic end diastolic diameter and end systolic diameter in a concentration-dependent manner. Significant reductions in lymphatic tone and contraction amplitude were observed after treatment 1–10 μM H1152 or 25–50 μM Y-27632. H1152 (10 μM) also significantly reduced contraction frequency. Transient increases in [Ca2+]i preceded each phasic contraction, however this pattern was disrupted by either 10 μM H1152 or 50 μM Y-27632 in the majority of lymphatics studied. The significant decrease in tone caused by H1152 or Y-27632 was not associated with a significant change in the basal [Ca2+]i between transients. Transfection with ca-ROCK protein enhanced lymphatic tone, but was not associated with a significant change in basal [Ca2+]i. Our data suggest that ROCK mediates normal tonic constriction and influences phasic contractions in lymphatics. We propose

  3. Rho kinase enhances contractions of rat mesenteric collecting lymphatics.

    PubMed

    Kurtz, Kristine H; Souza-Smith, Flavia M; Moor, Andrea N; Breslin, Jerome W

    2014-01-01

    The mechanisms that control phasic and tonic contractions of lymphatic vessels are poorly understood. We hypothesized that rho kinase ROCK, previously shown to increase calcium (Ca2+) sensitivity in vascular smooth muscle, enhances lymphatic contractile activity in a similar fashion. Contractions of isolated rat mesenteric lymphatic vessels were observed at a luminal pressure of 2 cm H2O in a 37°C bath. The expression of ROCK in isolated rat mesenteric lymphatic vessels was assessed by Western blotting and confocal microscopy. The role of ROCK in contractile function was tested using two specific yet structurally distinct inhibitors: H1152 (0.1-10 μM) and Y-27632 (0.5-50 μM). In addition, lymphatics were transfected with constitutively active (ca)-ROCK protein (2 μg/ml) to assess gain of contractile function. Vessel diameter and the concentration of intracellular free Ca2+ ([Ca2+]i) were simultaneously measured in a subset of isolated lymphatics loaded with the Ca2+-sensing dye fura-2. The results show expression of both the ROCK1 and ROCK2 isoforms in lymphatic vessels. Inhibition of ROCK increased lymphatic end diastolic diameter and end systolic diameter in a concentration-dependent manner. Significant reductions in lymphatic tone and contraction amplitude were observed after treatment 1-10 μM H1152 or 25-50 μM Y-27632. H1152 (10 μM) also significantly reduced contraction frequency. Transient increases in [Ca2+]i preceded each phasic contraction, however this pattern was disrupted by either 10 μM H1152 or 50 μM Y-27632 in the majority of lymphatics studied. The significant decrease in tone caused by H1152 or Y-27632 was not associated with a significant change in the basal [Ca2+]i between transients. Transfection with ca-ROCK protein enhanced lymphatic tone, but was not associated with a significant change in basal [Ca2+]i. Our data suggest that ROCK mediates normal tonic constriction and influences phasic contractions in lymphatics. We propose that

  4. Quantitative imaging of lymphatic function with liposomal indocyanine green.

    PubMed

    Proulx, Steven T; Luciani, Paola; Derzsi, Stefanie; Rinderknecht, Matthias; Mumprecht, Viviane; Leroux, Jean-Christophe; Detmar, Michael

    2010-09-15

    Lymphatic vessels play a major role in cancer progression and in postsurgical lymphedema, and several new therapeutic approaches targeting lymphatics are currently being developed. Thus, there is a critical need for quantitative imaging methods to measure lymphatic flow. Indocyanine green (ICG) has been used for optical imaging of the lymphatic system, but it is unstable in solution and may rapidly enter venous capillaries after local injection. We developed a novel liposomal formulation of ICG (LP-ICG), resulting in vastly improved stability in solution and an increased fluorescence signal with a shift toward longer wavelength absorption and emission. When injected intradermally to mice, LP-ICG was specifically taken up by lymphatic vessels and allowed improved visualization of deep lymph nodes. In a genetic mouse model of lymphatic dysfunction, injection of LP-ICG showed no enhancement of draining lymph nodes and slower clearance from the injection site. In mice bearing B16 luciferase-expressing melanomas expressing vascular endothelial growth factor-C (VEGF-C), sequential near-IR imaging of intradermally injected LP-ICG enabled quantification of lymphatic flow. Increased flow through draining lymph nodes was observed in mice bearing VEGF-C-expressing tumors without metastases, whereas a decreased flow pattern was seen in mice with a higher lymph node tumor burden. This new method will likely facilitate quantitative studies of lymphatic function in preclinical investigations and may also have potential for imaging of lymphedema or improved sentinel lymph detection in cancer. PMID:20823159

  5. Lymphatic disorders after renal transplantation: new insights for an old complication

    PubMed Central

    Ranghino, Andrea; Segoloni, Giuseppe Paolo; Lasaponara, Fedele; Biancone, Luigi

    2015-01-01

    In renal transplanted patients, lymphoceles and lymphorrhea are well-known lymphatic complications. Surgical damage of the lymphatics of the graft during the procurement and of the lymphatic around the iliac vessels of the recipients has been associated with development of lymphatic complications. However, lymphatic complications may be related to medical factors such as diabetes, obesity, blood coagulation abnormalities, anticoagulation prophylaxis, high dose of diuretics, delay in graft function and immunosuppressive drugs. Consistently, immunosuppression regimens based on the use of mTOR inhibitors, especially in association with steroids and immediately after transplantation, has been associated with a high risk to develop lymphocele or lymphorrhea. In addition, several studies have demonstrated the association between rejection episodes and lymphatic complications. However, before the discovery of reliable markers of lymphatic vessels, the pathogenic mechanisms underlining the development of lymphatic complications during rejection and the influence of mTOR inhibitors remained not fully understood. The recent findings on the lymphatic systems of either native or transplanted kidneys together with the advances achieved on lymphangiogenesis shared some lights on the pathogenesis of lymphatic complications after renal transplantation. In this review, we describe the surgical and medical causes of lymphatic complications focusing on the rejection and immunosuppressive drugs as causes of lymphatic complications. PMID:26413290

  6. Angiopoietin 2 regulates the transformation and integrity of lymphatic endothelial cell junctions

    PubMed Central

    Zheng, Wei; Nurmi, Harri; Appak, Sila; Sabine, Amélie; Bovay, Esther; Korhonen, Emilia A.; Orsenigo, Fabrizio; Lohela, Marja; D’Amico, Gabriela; Holopainen, Tanja; Leow, Ching Ching; Dejana, Elisabetta; Petrova, Tatiana V.; Augustin, Hellmut G.; Alitalo, Kari

    2014-01-01

    Primitive lymphatic vessels are remodeled into functionally specialized initial and collecting lymphatics during development. Lymphatic endothelial cell (LEC) junctions in initial lymphatics transform from a zipper-like to a button-like pattern during collecting vessel development, but what regulates this process is largely unknown. Angiopoietin 2 (Ang2) deficiency leads to abnormal lymphatic vessels. Here we found that an ANG2-blocking antibody inhibited embryonic lymphangiogenesis, whereas endothelium-specific ANG2 overexpression induced lymphatic hyperplasia. ANG2 inhibition blocked VE-cadherin phosphorylation at tyrosine residue 685 and the concomitant formation of button-like junctions in initial lymphatics. The defective junctions were associated with impaired lymph uptake. In collecting lymphatics, adherens junctions were disrupted, and the vessels leaked upon ANG2 blockade or gene deletion. ANG2 inhibition also suppressed the onset of lymphatic valve formation and subsequent valve maturation. These data identify ANG2 as the first essential regulator of the functionally important interendothelial cell–cell junctions that form during lymphatic development. PMID:25030698

  7. Angiopoietin 2 regulates the transformation and integrity of lymphatic endothelial cell junctions.

    PubMed

    Zheng, Wei; Nurmi, Harri; Appak, Sila; Sabine, Amélie; Bovay, Esther; Korhonen, Emilia A; Orsenigo, Fabrizio; Lohela, Marja; D'Amico, Gabriela; Holopainen, Tanja; Leow, Ching Ching; Dejana, Elisabetta; Petrova, Tatiana V; Augustin, Hellmut G; Alitalo, Kari

    2014-07-15

    Primitive lymphatic vessels are remodeled into functionally specialized initial and collecting lymphatics during development. Lymphatic endothelial cell (LEC) junctions in initial lymphatics transform from a zipper-like to a button-like pattern during collecting vessel development, but what regulates this process is largely unknown. Angiopoietin 2 (Ang2) deficiency leads to abnormal lymphatic vessels. Here we found that an ANG2-blocking antibody inhibited embryonic lymphangiogenesis, whereas endothelium-specific ANG2 overexpression induced lymphatic hyperplasia. ANG2 inhibition blocked VE-cadherin phosphorylation at tyrosine residue 685 and the concomitant formation of button-like junctions in initial lymphatics. The defective junctions were associated with impaired lymph uptake. In collecting lymphatics, adherens junctions were disrupted, and the vessels leaked upon ANG2 blockade or gene deletion. ANG2 inhibition also suppressed the onset of lymphatic valve formation and subsequent valve maturation. These data identify ANG2 as the first essential regulator of the functionally important interendothelial cell-cell junctions that form during lymphatic development. PMID:25030698

  8. Angiopoietin 2 regulates the transformation and integrity of lymphatic endothelial cell junctions.

    PubMed

    Zheng, Wei; Nurmi, Harri; Appak, Sila; Sabine, Amélie; Bovay, Esther; Korhonen, Emilia A; Orsenigo, Fabrizio; Lohela, Marja; D'Amico, Gabriela; Holopainen, Tanja; Leow, Ching Ching; Dejana, Elisabetta; Petrova, Tatiana V; Augustin, Hellmut G; Alitalo, Kari

    2014-07-15

    Primitive lymphatic vessels are remodeled into functionally specialized initial and collecting lymphatics during development. Lymphatic endothelial cell (LEC) junctions in initial lymphatics transform from a zipper-like to a button-like pattern during collecting vessel development, but what regulates this process is largely unknown. Angiopoietin 2 (Ang2) deficiency leads to abnormal lymphatic vessels. Here we found that an ANG2-blocking antibody inhibited embryonic lymphangiogenesis, whereas endothelium-specific ANG2 overexpression induced lymphatic hyperplasia. ANG2 inhibition blocked VE-cadherin phosphorylation at tyrosine residue 685 and the concomitant formation of button-like junctions in initial lymphatics. The defective junctions were associated with impaired lymph uptake. In collecting lymphatics, adherens junctions were disrupted, and the vessels leaked upon ANG2 blockade or gene deletion. ANG2 inhibition also suppressed the onset of lymphatic valve formation and subsequent valve maturation. These data identify ANG2 as the first essential regulator of the functionally important interendothelial cell-cell junctions that form during lymphatic development.

  9. Near-Infrared Fluorescence Lymphatic Imaging to Reconsider Occlusion Pressure of Superficial Lymphatic Collectors in Upper Extremities of Healthy Volunteers

    PubMed Central

    Vandermeeren, Liesbeth; Vankerckhove, Sophie; Valsamis, Jean-Baptiste; Malloizel-Delaunay, Julie; Moraine, Jean-Jacques; Liebens, Fabienne

    2016-01-01

    Abstract Background: There are very little scientific data on occlusion pressure for superficial lymphatic collectors. Given its importance in determining the transport capacity of lymphatic vessels, it is crucial to know its value. The novel method of near-infrared fluorescence lymphatic imaging (NIRFLI) can be used to visualize lymphatic flow in real time. The goal of this study was to see if this method could be used to measure the lymphatic occlusion pressure. Methods: We observed and recorded lymph flow in the upper limb of healthy volunteers through a transparent cuff using near-infrared fluorescence lymphatic imaging. After obtaining a baseline of the lymph flow without pressure inside the cuff, the cuff was inflated by increments of 10 mm Hg starting at 30 mm Hg. A NIRFLI guided manual lymphatic drainage technique named “Fill & Flush Drainage Method” was performed during the measurement to promote lymph flow. Lymphatic occlusion pressure was determined by observing when lymph flow stopped under the cuff. Results: We measured the lymphatic occlusion pressure on 30 healthy volunteers (11 men and 19 women). Mean lymphatic occlusion pressure in the upper limb was 86 mm Hg (CI ±3.7 mm Hg, α = 0.5%). No significant differences were found between age groups (p = 0.18), gender (p = 0.12), or limb side (p = 0.85). Conclusions: NIRFLI, a transparent sphygmomanometer cuff and the “Fill and Flush” manual lymphatic drainage method were used to measure the lymphatic occlusion pressure in 30 healthy humans. That combination of these techniques allows the visualization of the lymph flow in real time, while ensuring the continuous filling of the lymph collectors during the measurement session, reducing false negative observations. The measured occlusion pressures are much higher than previously described in the medical literature. PMID:27167187

  10. Primary afferent depolarization and frequency processing in auditory afferents.

    PubMed

    Baden, Tom; Hedwig, Berthold

    2010-11-01

    Presynaptic inhibition is a widespread mechanism modulating the efficiency of synaptic transmission and in sensory pathways is coupled to primary afferent depolarizations. Axonal terminals of bush-cricket auditory afferents received 2-5 mV graded depolarizing inputs, which reduced the amplitude of invading spikes and indicated presynaptic inhibition. These inputs were linked to a picrotoxin-sensitive increase of Ca(2+) in the terminals. Electrophysiological recordings and optical imaging showed that in individual afferents the sound frequency tuning based on spike rates was different from the tuning of the graded primary afferent depolarizations. The auditory neuropil of the bush-cricket Mecopoda elongata is tonotopically organized, with low frequencies represented anteriorly and high frequencies represented posteriorly. In contrast graded depolarizing inputs were tuned to high-frequencies anteriorly and to low-frequencies posteriorly. Furthermore anterior and posterior axonal branches of individual afferents received different levels of primary afferent depolarization depending on sound frequency. The presence of primary afferent depolarization in the afferent terminals indicates that presynaptic inhibition may shape the synaptic transmission of frequency-specific activity to auditory interneurons.

  11. Mesenchymal status of lymphatic endothelial cell: enlightening treatment of lymphatic malformation.

    PubMed

    Cai, Xu; Zhang, Wei; Chen, Gang; Li, Rui-Fang; Sun, Yan-Fang; Zhao, Yi-Fang

    2015-01-01

    In contrast to blood capillaries, lymphatic capillaries in peripheral tissues are composed of a single-cell layer of lymphatic endothelial cells (LECs) without a covering of mural cells. However, in lymphatic malformations, the enlarged lymphatic vessels were covered with mural cells. This study aimed to understand the molecular mechanism of differences between human dermal lymphatic endothelial cells (HDLECs) and human umbilical vein endothelial cells (HUVECs) and to determine the changes of LECs in the pathological condition of lymphatic malformation. Results showed that HDLECs exhibited lower expression of endothelial proteins, including VE-cadherin and CD31, than HUVECs; HDLECs also showed higher expression of mesenchymal proteins, including α-SMA, SM22α, calponin, and epithelial mesenchymal transition-related transcription factor Slug, than HUVECs. Likewise, HDLECs displayed higher permeability and weaker recruitment of SMCs than HUVECs; HDLECs also exhibited low PDGF-BB expression. TGF-β2 treatment and FGF2 depletion enhanced mesenchymal marker expression with increased permeability and reduced SMC recruitment. By contrast, Slug depletion in HDLECs enhanced VE-cadherin expression, inhibited α-SMA expression, decreased permeability, and enhanced PDGF-BB expression. These results suggested that HDLECs were in a mesenchymal status, which contributed to their functions and might determine their identities. Our data also revealed that miR143/145 was implicated in the mesenchymal status of HDLECs. In lymphatic malformations (LMs) treated with OK-432 sclerotherapy, immunohistochemistry results showed that Prox1 expression was reduced and mural cell investment was increased; these results indicated that LECs lost their mesenchymal status after OK-432 treatment was administered. The decreased mesenchymal status of LECs in LMs may induce dilated vessel constriction, which could be the mechanism of OK-432 sclerotherapy. PMID:26550134

  12. Development, plasticity and modulation of visceral afferents

    PubMed Central

    Christianson, Julie A.; Bielefeldt, Klaus; Altier, Christophe; Cenac, Nicolas; Davis, Brian M.; Gebhart, Gerald F.; High, Karin W.; Kollarik, Marian; Randich, Alan; Undem, Brad; Vergnolle, Nathalie

    2010-01-01

    Visceral pain is the most common reason for doctor visits in the US. Like somatic pain, virtually all visceral pain sensations begin with the activation of primary sensory neurons innervating the viscera and/or the blood vessels associated with these structures. Visceral afferents also play a central role in tissue homeostasis. Recent studies show that in addition to monitoring the state of the viscera, they perform efferent functions through the release of small molecules (e.g. peptides like CGRP) that can drive inflammation, thereby contributing to the development of visceral pathologies (e.g. diabetes Razavi, R., Chan, Y., Afifiyan, F.N., Liu, X.J., Wan, X., Yantha, J., Tsui, H., Tang, L., Tsai, S., Santamaria, P., Driver, J.P., Serreze, D., Salter, M.W., Dosch, H.M., 2006. TRPV1+ sensory neurons control beta cell stress and islet inflammation in autoimmune diabetes, Cell 127 1123–1135). Visceral afferents are heterogeneous with respect to their anatomy, neurochemistry and function. They are also highly plastic in that their cellular environment continuously influences their response properties. This plasticity makes them susceptible to long-term changes that may contribute significantly to the development of persistent pain states such as those associated with irritable bowel syndrome, pancreatitis, and visceral cancers. This review examines recent insights into visceral afferent anatomy and neurochemistry and how neonatal insults can affect the function of these neurons in the adult. New approaches to the treatment of visceral pain, which focus on primary afferents, will also be discussed. PMID:19150371

  13. Sensitivity analysis of near-infrared functional lymphatic imaging

    NASA Astrophysics Data System (ADS)

    Weiler, Michael; Kassis, Timothy; Dixon, J. Brandon

    2012-03-01

    Background - Near-infrared (NIR) imaging of lymphatic drainage of injected indocyanine green (ICG) has emerged as a new technology for clinical imaging of lymphatic architecture and quantification of vessel function, offering better spatial and temporal resolution than competing imaging modalities. While NIR lymphatic imaging has begun to be reported in the literature, the technology is still in its infancy and its imaging capabilities have yet to be quantitatively characterized. The objective of this study, therefore, was to characterize the parameters of NIR lymphatic imaging to quantify its capabilities as a diagnostic tool for evaluating lymphatic disease. Methods - An NIR imaging system was developed using a laser diode for excitation, ICG as a fluorescent agent, and a CCD camera to detect emission. A tissue phantom with mock lymphatic vessels of known depths and diameters was used as an alternative to in vivo lymphatic vessels due to the greater degree of control with the phantom. Results and Conclusions - When dissolved in an albumin physiological salt solution (APSS) to mimic interstitial fluid, ICG experiences shifts in the excitation/emission wavelengths such that it is maximally excited at 805nm and produces peak fluorescence at 840nm. Premixing ICG with albumin induces greater fluorescence intensity, with the ideal concentration being: 900μM (60g/L) albumin and 193.5μM (150μg/mL) ICG. ICG fluorescence can be detected as deep as 6mm, but spatial resolution deteriorates severely below 3mm, thus skewing vessel geometry measurements. ICG packet travel, a common measure of lymphatic transport, can be detected as deep as 5mm.

  14. Mast cells drive mesenteric afferent signalling during acute intestinal ischaemia

    PubMed Central

    Jiang, Wen; Kirkup, Anthony J; Grundy, David

    2011-01-01

    Abstract Acute intestinal ischaemia stimulates visceral afferent nerves but the mechanisms responsible for this excitation are not fully understood. Mast cells may participate in this process as they are known to signal to mesenteric afferents during intestinal anaphylaxis and contribute to early inflammation and neuronal damage in response to cerebral ischaemia. We therefore hypothesised that mast cells are early responders to acute intestinal ischaemia and their activation initiates rapid signalling to the CNS via the excitation of mesenteric afferents. Primary afferent firing was recorded from a mesenteric nerve bundle supplying a segment of jejunum in anaesthetized adult rats. Acute focal ischaemia was produced by clamping the mesenteric vessels for 8 min, and reperfusion followed removal of the vessel clip. Two episodes of ischaemia–reperfusion (I–R) separated by a 30 min interval were performed. Drugs or their vehicles were administered 10 min before the 2nd I–R episode. Ischaemia caused a reproducible, intense and biphasic afferent firing that was temporally dissociated from the concomitantly triggered complex pattern of intestinal motor activity. The L-type calcium channel blocker, nifedipine, significantly attenuated this afferent firing by a mechanism independent of its action on intestinal tone. Ischaemia-induced afferent firing was also abrogated by the mast cell stabilizer, doxantrazole, and the H1 histamine receptor antagonist, pyrilamine. In contrast, the nicotinic receptor antagonist, hexamethonium, and the N-type calcium channel toxin, ω-conotoxin GVIA, each reduced the ischaemia-evoked motor inhibition but not the concurrent afferent discharge. Similarly, the cyclooxygenase inhibitor, naproxen, had no effect on the ischaemic afferent response but reduced the intestinal tone shortly from the onset of ischaemia to the early period of reperfusion. These data support a critical role for mast cell-derived histamine in the direct chemoexcitation

  15. Lymphatic vascular morphogenesis in development, physiology, and disease.

    PubMed

    Schulte-Merker, Stefan; Sabine, Amélie; Petrova, Tatiana V

    2011-05-16

    The lymphatic vasculature constitutes a highly specialized part of the vascular system that is essential for the maintenance of interstitial fluid balance, uptake of dietary fat, and immune response. Recently, there has been an increased awareness of the importance of lymphatic vessels in many common pathological conditions, such as tumor cell dissemination and chronic inflammation. Studies of embryonic development and genetically engineered animal models coupled with the discovery of mutations underlying human lymphedema syndromes have contributed to our understanding of mechanisms regulating normal and pathological lymphatic morphogenesis. It is now crucial to use this knowledge for the development of novel therapies for human diseases.

  16. Lymph transport in rat mesenteric lymphatics experiencing edemagenic stress

    PubMed Central

    Rahbar, Elaheh; Akl, Tony; Coté, Gerard L.; Moore, James E.; Zawieja, David C.

    2014-01-01

    Objective To assess lymphatic flow adaptations to edema, we evaluated lymph transport function in rat mesenteric lymphatics under normal and edemagenic conditions in situ. Methods Twelve rats were infused with saline (intravenous infusion, 0.2 ml/min/100g body weight) to induce edema. We intravitally measured mesenteric lymphatic diameter and contraction frequency, as well as immune cell velocity and density before, during and after infusion. Results A 10-fold increase in lymph velocity (0.1–1 mm/s) and a 6-fold increase in flow rate (0.1–0.6 μL/min), were observed post-infusion, respectively. There were also increases in contraction frequency and fractional pump flow 1-minute post-infusion. Time-averaged wall shear stress increased 10 fold post-infusion to nearly 1.5 dynes/cm2. Similarly, maximum shear stress rose from 5 dynes/cm2 to 40 dynes/cm2. Conclusions Lymphatic vessels adapted to edemagenic stress by increasing lymph transport. Specifically, the increases in lymphatic contraction frequency, lymph velocity, and shear stress were significant. Lymph pumping increased post-infusion, though changes in lymphatic diameter were not statistically significant. These results indicate that edemagenic conditions stimulate lymph transport via increases in lymphatic contraction frequency, lymph velocity and flow. These changes, consequently, resulted in large increases in wall shear stress, which could then activate NO pathways and modulate lymphatic transport function. PMID:24397756

  17. An investigation of the topography of the lymphatic system of the grey kangaroo (Macropus giganteus). 1. The superficial lymphatic system.

    PubMed Central

    Hopwood, P R

    1988-01-01

    The superficial lymphatic system of the grey kangaroo, Macropus giganteus is described. The description is based on dissections of 130 eastern grey kangaroos. The most significant difference found between the superficial lymphatic drainage pattern of kangaroos and that of the domestic species was the existence of large inguino-axillary lymphatic trunks in the kangaroo. Thus in the kangaroo, instead of lymph passing from the inguinal lymphocentre to the lumbar lymphatic trunks as is the situation in the domestic animals, lymph passes from the inguinal lymphocentre to the axillary lymphocentre. Apart from the lymph draining from the head and ventral neck (which passes to the superficial cervical lymphocentre) and lymph which may pass from the superficial lymphatic vessels to deeper lymphatic vessels, all the superficial lymphatic drainage of the kangaroo passes through the axillary lymphocentre. From the viewpoint of the meat inspection of the carcasses of kangaroos taken as game meat animals, pathology of the axillary lymphocentre may reflect disease in a much wider range of body regions than it would in a domestic animal. PMID:3198478

  18. FOXC2 and fluid shear stress stabilize postnatal lymphatic vasculature.

    PubMed

    Sabine, Amélie; Bovay, Esther; Demir, Cansaran Saygili; Kimura, Wataru; Jaquet, Muriel; Agalarov, Yan; Zangger, Nadine; Scallan, Joshua P; Graber, Werner; Gulpinar, Elgin; Kwak, Brenda R; Mäkinen, Taija; Martinez-Corral, Inés; Ortega, Sagrario; Delorenzi, Mauro; Kiefer, Friedemann; Davis, Michael J; Djonov, Valentin; Miura, Naoyuki; Petrova, Tatiana V

    2015-10-01

    Biomechanical forces, such as fluid shear stress, govern multiple aspects of endothelial cell biology. In blood vessels, disturbed flow is associated with vascular diseases, such as atherosclerosis, and promotes endothelial cell proliferation and apoptosis. Here, we identified an important role for disturbed flow in lymphatic vessels, in which it cooperates with the transcription factor FOXC2 to ensure lifelong stability of the lymphatic vasculature. In cultured lymphatic endothelial cells, FOXC2 inactivation conferred abnormal shear stress sensing, promoting junction disassembly and entry into the cell cycle. Loss of FOXC2-dependent quiescence was mediated by the Hippo pathway transcriptional coactivator TAZ and, ultimately, led to cell death. In murine models, inducible deletion of Foxc2 within the lymphatic vasculature led to cell-cell junction defects, regression of valves, and focal vascular lumen collapse, which triggered generalized lymphatic vascular dysfunction and lethality. Together, our work describes a fundamental mechanism by which FOXC2 and oscillatory shear stress maintain lymphatic endothelial cell quiescence through intercellular junction and cytoskeleton stabilization and provides an essential link between biomechanical forces and endothelial cell identity that is necessary for postnatal vessel homeostasis. As FOXC2 is mutated in lymphedema-distichiasis syndrome, our data also underscore the role of impaired mechanotransduction in the pathology of this hereditary human disease.

  19. FOXC2 and fluid shear stress stabilize postnatal lymphatic vasculature

    PubMed Central

    Sabine, Amélie; Bovay, Esther; Demir, Cansaran Saygili; Kimura, Wataru; Jaquet, Muriel; Agalarov, Yan; Zangger, Nadine; Scallan, Joshua P.; Graber, Werner; Gulpinar, Elgin; Kwak, Brenda R.; Mäkinen, Taija; Martinez-Corral, Inés; Ortega, Sagrario; Delorenzi, Mauro; Kiefer, Friedemann; Davis, Michael J.; Djonov, Valentin; Miura, Naoyuki; Petrova, Tatiana V.

    2015-01-01

    Biomechanical forces, such as fluid shear stress, govern multiple aspects of endothelial cell biology. In blood vessels, disturbed flow is associated with vascular diseases, such as atherosclerosis, and promotes endothelial cell proliferation and apoptosis. Here, we identified an important role for disturbed flow in lymphatic vessels, in which it cooperates with the transcription factor FOXC2 to ensure lifelong stability of the lymphatic vasculature. In cultured lymphatic endothelial cells, FOXC2 inactivation conferred abnormal shear stress sensing, promoting junction disassembly and entry into the cell cycle. Loss of FOXC2-dependent quiescence was mediated by the Hippo pathway transcriptional coactivator TAZ and, ultimately, led to cell death. In murine models, inducible deletion of Foxc2 within the lymphatic vasculature led to cell-cell junction defects, regression of valves, and focal vascular lumen collapse, which triggered generalized lymphatic vascular dysfunction and lethality. Together, our work describes a fundamental mechanism by which FOXC2 and oscillatory shear stress maintain lymphatic endothelial cell quiescence through intercellular junction and cytoskeleton stabilization and provides an essential link between biomechanical forces and endothelial cell identity that is necessary for postnatal vessel homeostasis. As FOXC2 is mutated in lymphedema-distichiasis syndrome, our data also underscore the role of impaired mechanotransduction in the pathology of this hereditary human disease. PMID:26389677

  20. Expansion of the lymphatic vasculature in cancer and inflammation: new opportunities for in vivo imaging and drug delivery.

    PubMed

    Proulx, Steven T; Luciani, Paola; Dieterich, Lothar C; Karaman, Sinem; Leroux, Jean-Christophe; Detmar, Michael

    2013-12-10

    Over the last 15 years, discovery of key growth factors and specific molecular markers for lymphatic vessels has enabled a new era of molecular research on the lymphatic vascular system. As a result, it has been found that lymphangiogenesis, the expansion of existing lymphatic vessels, plays an important role in tumor progression and in the control of chronic inflammation. At the same time, technical advancements have been made to improve the visualization of the lymphatic system. We have recently developed liposomal and polymer-based formulations of near-infrared lymphatic-specific imaging tracers for the non-invasive quantitative in vivo imaging of lymphatic vessel function. Using these tracers, a near-infrared stereomicroscope system allows imaging of initial and collecting lymphatic vessels with high spatial and temporal resolution in mice. In addition, we have developed a new method, using antibodies to a lymphatic specific marker and positron emission tomography, to sensitively detect lymphatic expansion in lymph nodes as the earliest sign of cancer metastasis. These imaging methods have great potential to provide non-invasive measures to assess the functionality of the lymphatic system and to assess the efficiency of lymphatic drug delivery.

  1. Cell recruitment and antigen trafficking in afferent lymph after injection of antigen and poly(I:C) containing liposomes, in aqueous or oil-based formulations.

    PubMed

    de Veer, Michael; Neeland, Melanie; Burke, Melissa; Pleasance, Jill; Nathanielsz, Jackie; Elhay, Martin; Meeusen, Els

    2013-02-01

    After vaccination, innate cell populations transport antigen from the tissue, via the afferent lymphatic vessels, into the local lymph node where they provide critical signals for the generation of an adaptive immune response. The present study uses a unique lymphatic cannulation model to examine, in real time, changes in afferent lymph after injection of a liposome-based delivery system, incorporating diptheria toxoid (DT) and the innate stimulator, poly(I:C). There was a dramatic but temporal recruitment of innate cell populations over time, with neutrophils and monocytes peaking at 6h and 28h post vaccination respectively. The number of dendritic cells (DC) did not increase over the 198h time period, while lymphocytes were slightly elevated at the latest times, indicating the start of an adaptive response. Monocytes and neutrophils were the predominant cell types transporting antigen at the early time points while DC were the most dominant antigen-carrying cells after 78h, predominantly the Sirp-α(high) DC subtype. Resuspending liposomes in oil instead of aqueous solutions has recently been shown to dramatically increase the level and persistence of an immune response and forms the basis of the novel adjuvant formulations, Vaccimax© and Depovax©. In the present study, formulation of the DT and poly(I:C) containing liposomes in an oil carrier dramatically reduced antigen transport to the draining lymph nodes. Examination of the injection site revealed the creation of an ectopic lymphoid tissue with prominent antigen foci and organized lymphoid cells, providing a possible mechanism for the persistence of an immune response in liposome-in-oil adjuvant formulation. Together, the present studies demonstrate the real-time innate in vivo response to vaccination of two novel liposome-based adjuvant systems and the dramatic effect of different carrier formulations.

  2. Lack of functioning intratumoral lymphatics in colon and pancreas cancer tissue.

    PubMed

    Olszewski, Waldemar L; Stanczyk, Marek; Gewartowska, Magdalena; Domaszewska-Szostek, Anna; Durlik, Marek

    2012-09-01

    There are controversial views as to whether intratumoral or peritumoral lymphatics play a dominant role in the metastatic process. Most clinical observations originate from studies of colon cancer. Colon contains mucosa and submucosa rich in lymphatics and with high lymph formation rate. This seems to be a prerequisite for easy metastasis of cancer cells to regional lymph nodes. However, there are other tissues as pancreas with a rudimentary lymphatic network where cancer metastasis formation is as intensive as in colon cancer. This contradicts the common notion that intratumor lymphatics play major role in metastases. We visualized interstitial space and lymphatics in the central and peripheral regions of colon and pancreas tumors using the color stereoscopic lymphography and simultaneously immunohistochemical performed stainings specific for lymphatic and blood endothelial cells. The density of open and compressed lymphatic and blood vessels was measured in the tumor core and edge. There were very few lymphatics in the colon and pancreas tumor core but numerous minor fluid "lakes" with no visible connection to the peritumoral lymphatics. Lining of "lakes" did not express molecular markers specific for lymphatic endothelial cells. Dense connective tissue surrounding tumor foci did not contain lymphatics. Peritumoral lymphatics were irregularly distributed in both types of tumor and only sporadically contained cells that might be tumor cells. Similar lymphoscintigraphic and histological pictures were seen in colon and pancreas cancer despite of different structure of both tissues. This suggests a uniform reaction of tissues to the growing cancer irrespective of the affected organ.

  3. Lymphatics and the breast

    MedlinePlus

    ... is often referred to as the body's "secondary circulatory system." The lymphatic system collects excess fluid in ... the exchange of fluid and molecules between the blood circulation and body tissues, blood capillaries may not reabsorb ...

  4. The lymphatic vascular system in liver diseases: its role in ascites formation.

    PubMed

    Chung, Chuhan; Iwakiri, Yasuko

    2013-06-01

    The lymphatic system is part of the circulatory system and plays a key role in normal vascular function. Its failure plays a crucial role in the development and maintenance of various diseases including liver diseases. Lymphangiogenesis (the growth of lymphatic vessels) and changes in the properties of lymphatic vessels are associated with pathogenesis of tumor metastases, ascites formation, liver fibrosis/cirrhosis and portal hypertension. Despite its significant role in liver diseases and its importance as a potential therapeutic target for those diseases, the lymphatic vascular system of the liver is poorly understood. Therefore, how the lymphatic vascular system in general and lymphangiogenesis in particular are mechanistically related to the pathogenesis and maintenance of liver diseases are largely unknown. This article summarizes: 1) the lymphatic vascular system; 2) its role in liver tumors, liver fibrosis/cirrhosis and portal hypertension; and 3) its role in ascites formation.

  5. Lymphatic Mapping in the Treatment of Chronic Seroma: A Case Series

    PubMed Central

    Aliano, Kristen; Stavrides, Steven; Davenport, Thomas

    2015-01-01

    Objective: Seromas or lymphoceles are common postoperative complications. This series presents 3 patients with lower extremity seromas refractory to treatment that required lymphatic mapping and lymphatic ligation for closure, and in 1 case, diagnosis. Methods: Lymphatic mapping procedure consisted of intraoperative injection of subcutaneous tissue with methylene blue distal to the seroma with observation of dye effluence from transected or injured lymphatics draining into area of seroma. Results: In 2 patients, methylene blue dye absorption into lymphatic vessels allowed for optimized visual identification of lymphatic leak and contrast against surrounding tissues. In the third patient, where no lymphocele leak was found, the study was diagnostic and helped to find an alternate etiology for the recurrent seroma. Conclusion: Lymphatic mapping with methylene blue dye is an effective tool in the evaluation and diagnosis of chronic seroma. PMID:25848444

  6. Primary and secondary lymphatic valve development: molecular, functional and mechanical insights.

    PubMed

    Bazigou, Eleni; Wilson, John T; Moore, James E

    2014-11-01

    Fluid homeostasis in vertebrates critically relies on the lymphatic system forming a hierarchical network of lymphatic capillaries and collecting lymphatics, for the efficient drainage and transport of extravasated fluid back to the cardiovascular system. Blind-ended lymphatic capillaries employ specialized junctions and anchoring filaments to encourage a unidirectional flow of the interstitial fluid into the initial lymphatic vessels, whereas collecting lymphatics are responsible for the active propulsion of the lymph to the venous circulation via the combined action of lymphatic muscle cells and intraluminal valves. Here we describe recent findings on molecular and physical factors regulating the development and maturation of these two types of valves and examine their role in tissue-fluid homeostasis.

  7. Search for lymphatic drainage of the monkey orbit

    SciTech Connect

    McGetrick, J.J.; Wilson, D.G.; Dortzbach, R.K.; Kaufman, P.L.; Lemke, B.N.

    1989-02-01

    Colloid solutions of technetium Tc-99m and india ink injected into the retrobulbar space of the cynomolgus monkey outside the extraocular muscle cone were removed from the orbit by the lymphatic vessels of the conjunctiva and eyelids and were then concentrated within the lymph nodes that drained the conjunctival and eyelid areas. Colloid solutions injected into the retrobulbar space inside the extraocular muscle cone did not reach the conjunctiva and did not collect in any lymph nodes over a 24-hour period. Within the orbit, the injected colloids spread along the planes of the connective-tissue septa. No lymphatic vessels were identified within the orbits posterior to the conjunctiva. Small amounts of india ink left the posterior orbit and ultimately entered the contralateral orbit. This posterior pathway did not lead to lymphatic vessels or lymph nodes and therefore does not appear to represent a prelymphatic pathway.

  8. An Immunological Fingerprint Differentiates Muscular Lymphatics from Arteries and Veins

    PubMed Central

    Bridenbaugh, Eric A.; Wang, Wei; Srimushnam, Maya; Cromer, Walter E.; Zawieja, Scott D.; Schmidt, Susan E.; Jupiter, Daniel C.; Huang, Hung-Chung; Van Buren, Vincent

    2013-01-01

    Abstract The principal function of the lymphatic system is to transport lymph from the interstitium to the nodes and then from the nodes to the blood. In doing so lymphatics play important roles in fluid homeostasis, macromolecular/antigen transport and immune cell trafficking. To better understand the genes that contribute to their unique physiology, we compared the transcriptional profile of muscular lymphatics (prenodal mesenteric microlymphatics and large, postnodal thoracic duct) to axillary and mesenteric arteries and veins isolated from rats. Clustering of the differentially expressed genes demonstrated that the lymph versus blood vessel differences were more profound than between blood vessels, particularly the microvessels. Gene ontology functional category analysis indicated that microlymphatics were enriched in antigen processing/presentation, IgE receptor signaling, catabolic processes, translation and ribosome; while they were diminished in oxygen transport, regulation of cell proliferation, glycolysis and inhibition of adenylate cyclase activity by G-proteins. We evaluated the differentially expressed microarray genes/products by qPCR and/or immunofluorescence. Immunofluorescence documented that multiple MHC class II antigen presentation proteins were highly expressed by an antigen-presenting cell (APC) type found resident within the lymphatic wall. These APCs also expressed CD86, a co-stimulatory protein necessary for T-cell activation. We evaluated the distribution and phenotype of APCs within the pre and postnodal lymphatic network. This study documents a novel population of APCs resident within the walls of muscular, prenodal lymphatics that indicates novel roles in antigen sampling and immune responses. In conclusion, these prenodal lymphatics exhibit a unique profile that distinguishes them from blood vessels and highlights the role of the lymphatic system as an immunovascular system linking the parenchymal interstitium, lymph nodes and the

  9. Restoration of lymphatic function rescues obesity in Prox1-haploinsufficient mice

    PubMed Central

    Proulx, Steven T.; Dillard, Miriam E.; Johnson, Nicole; Detmar, Michael

    2016-01-01

    Prox1 heterozygous mice have a defective lymphatic vasculature and develop late-onset obesity. Chyle abnormally leaks from those vessels, accumulates in the surrounding tissues, and causes an increase in adipose tissue. We characterized the lymphatics of Prox1+/– mice to determine whether the extent of obesity correlated with the severity of lymphatic defects. The lymphatic vasculature in Prox1+/– mice exhibited reduced tracer clearance from the ear skin, dysfunctional perfusion of the lower legs, and reduced tracer uptake into the deep lymphatic collectors during mechanostimulation prior to the onset of obesity. Ear lymphatic vessels and leg collectors in Prox1+/– mice were disorganized and irregular, further confirming that defective lymphatic vessels are associated with obesity in Prox1+/– mice. We now provide conclusive in vivo evidence that demonstrates that leaky lymphatics mediate obesity in Prox1+/– mice, as restoration of lymphatic vasculature function was sufficient to rescue the obesity features in Prox1+/– mice. Finally, depth-lipomic profiling of lymph contents showed that free fatty acids induce adipogenesis in vitro. PMID:26973883

  10. Immunopathogenesis of lymphatic filarial disease1

    PubMed Central

    Babu, Subash; Nutman, Thomas B.

    2012-01-01

    Although two-thirds of the 120 million people infected with lymph-dwelling filarial parasites have subclinical infections, ~ 40 million have lymphedema and/or other pathologic manifestations including hydroceles (and other forms of urogenital disease), episodic adenolymphangitis, tropical pulmonary eosinophilia, lymphedema, and (in its most severe form) elephantiasis. Adult filarial worms reside in the lymphatics and lymph nodes and induce changes that result in dilatation of lymphatics and thickening of the lymphatic vessel walls. Progressive lymphatic damage and pathology results from the summation of the effect of tissue alterations induced by both living and nonliving adult parasites, the host inflammatory response to the parasites and their secreted antigens, the host inflammatory response to the endosymbiont Wolbachia, and those seen as a consequence of secondary bacterial or fungal infections. Inflammatory damage induced by filarial parasites appears to be multifactorial, with endogenous parasite products, Wolbachia, and host immunity all playing important roles. This review will initially examine the prototypical immune responses engendered by the parasite and delineate the regulatory mechanisms elicited to prevent immune-mediated pathology. This will be followed by a discussion of the proposed mechanisms underlying pathogenesis, with the central theme being that pathogenesis is a two-step process - the first initiated by the parasite and host innate immune system and the second propagated mainly by the host’s adaptive immune system and by other factors (including secondary infections). PMID:23053393

  11. Sensitivity analysis of near-infrared functional lymphatic imaging

    NASA Astrophysics Data System (ADS)

    Weiler, Michael; Kassis, Timothy; Dixon, J. Brandon

    2012-06-01

    Near-infrared imaging of lymphatic drainage of injected indocyanine green (ICG) has emerged as a new technology for clinical imaging of lymphatic architecture and quantification of vessel function, yet the imaging capabilities of this approach have yet to be quantitatively characterized. We seek to quantify its capabilities as a diagnostic tool for lymphatic disease. Imaging is performed in a tissue phantom for sensitivity analysis and in hairless rats for in vivo testing. To demonstrate the efficacy of this imaging approach to quantifying immediate functional changes in lymphatics, we investigate the effects of a topically applied nitric oxide (NO) donor glyceryl trinitrate ointment. Premixing ICG with albumin induces greater fluorescence intensity, with the ideal concentration being 150 μg/mL ICG and 60 g/L albumin. ICG fluorescence can be detected at a concentration of 150 μg/mL as deep as 6 mm with our system, but spatial resolution deteriorates below 3 mm, skewing measurements of vessel geometry. NO treatment slows lymphatic transport, which is reflected in increased transport time, reduced packet frequency, reduced packet velocity, and reduced effective contraction length. NIR imaging may be an alternative to invasive procedures measuring lymphatic function in vivo in real time.

  12. Photoacoustic lymphatic imaging with high spatial-temporal resolution

    NASA Astrophysics Data System (ADS)

    Martel, Catherine; Yao, Junjie; Huang, Chih-Hsien; Zou, Jun; Randolph, Gwendalyn J.; Wang, Lihong V.

    2014-11-01

    Despite its critical function in coordinating the egress of inflammatory and immune cells out of tissues and maintaining fluid balance, the causative role of lymphatic network dysfunction in pathological settings is still understudied. Engineered-animal models and better noninvasive high spatial-temporal resolution imaging techniques in both preclinical and clinical studies will help to improve our understanding of different lymphatic-related pathologic disorders. Our aim was to take advantage of our newly optimized noninvasive wide-field fast-scanning photoacoustic (PA) microcopy system to coordinately image the lymphatic vasculature and its flow dynamics, while maintaining high resolution and detection sensitivity. Here, by combining the optical-resolution PA microscopy with a fast-scanning water-immersible microelectromechanical system scanning mirror, we have imaged the lymph dynamics over a large field-of-view, with high spatial resolution and advanced detection sensitivity. Depending on the application, lymphatic vessels (LV) were spectrally or temporally differentiated from blood vessels. Validation experiments were performed on phantoms and in vivo to identify the LV. Lymphatic flow dynamics in nonpathological and pathological conditions were also visualized. These results indicate that our newly developed PA microscopy is a promising tool for lymphatic-related biological research.

  13. Photoacoustic lymphatic imaging with high spatial-temporal resolution.

    PubMed

    Martel, Catherine; Yao, Junjie; Huang, Chih-Hsien; Zou, Jun; Randolph, Gwendalyn J; Wang, Lihong V

    2014-11-01

    Despite its critical function in coordinating the egress of inflammatory and immune cells out of tissues and maintaining fluid balance, the causative role of lymphatic network dysfunction in pathological settings is still understudied. Engineered-animal models and better noninvasive high spatial-temporal resolution imaging techniques in both preclinical and clinical studies will help to improve our understanding of different lymphatic-related pathologic disorders. Our aim was to take advantage of our newly optimized noninvasive wide-field fast-scanning photoacoustic (PA) microcopy system to coordinately image the lymphatic vasculature and its flow dynamics, while maintaining high resolution and detection sensitivity. Here, by combining the optical-resolution PA microscopy with a fast-scanning water-immersible microelectromechanical system scanning mirror, we have imaged the lymph dynamics over a large field-of-view, with high spatial resolution and advanced detection sensitivity. Depending on the application, lymphatic vessels (LV) were spectrally or temporally differentiated from blood vessels. Validation experiments were performed on phantoms and in vivo to identify the LV. Lymphatic flow dynamics in nonpathological and pathological conditions were also visualized. These results indicate that our newly developed PA microscopy is a promising tool for lymphatic-related biological research.

  14. Adipose veno-lymphatic transfer for management of post-radiation lymphedema

    SciTech Connect

    Pho, R.W.; Bayon, P.; Tan, L.

    1989-01-01

    In a patient who had post-radiation lymphedema after excision of liposarcoma, a method is described that is called adipose veno-lymphatic transfer. The technique involves transferring adipose tissue containing lymphatic vessels that surround the long saphenous vein, from the normal, healthy leg to the irradiated leg, with the creation of an arteriovenous fistula.

  15. Ischemia-Reperfusion Injury Enhances Lymphatic Endothelial VEGFR3 and Rejection in Cardiac Allografts.

    PubMed

    Dashkevich, A; Raissadati, A; Syrjälä, S O; Zarkada, G; Keränen, M A I; Tuuminen, R; Krebs, R; Anisimov, A; Jeltsch, M; Leppänen, V-M; Alitalo, K; Nykänen, A I; Lemström, K B

    2016-04-01

    Organ damage and innate immunity during heart transplantation may evoke adaptive immunity with serious consequences. Because lymphatic vessels bridge innate and adaptive immunity, they are critical in immune surveillance; however, their role in ischemia-reperfusion injury (IRI) in allotransplantation remains unknown. We investigated whether the lymphangiogenic VEGF-C/VEGFR3 pathway during cardiac allograft IRI regulates organ damage and subsequent interplay between innate and adaptive immunity. We found that cardiac allograft IRI, within hours, increased graft VEGF-C expression and lymphatic vessel activation in the form of increased lymphatic VEGFR3 and adhesion protein expression. Pharmacological VEGF-C/VEGFR3 stimulation resulted in early lymphatic activation and later increase in allograft inflammation. In contrast, pharmacological VEGF-C/VEGFR3 inhibition during cardiac allograft IRI decreased early lymphatic vessel activation with subsequent dampening of acute and chronic rejection. Genetic deletion of VEGFR3 specifically in the lymphatics of the transplanted heart recapitulated the survival effect achieved by pharmacological VEGF-C/VEGFR3 inhibition. Our results suggest that tissue damage rapidly changes lymphatic vessel phenotype, which, in turn, may shape the interplay of innate and adaptive immunity. Importantly, VEGF-C/VEGFR3 inhibition during solid organ transplant IRI could be used as lymphatic-targeted immunomodulatory therapy to prevent acute and chronic rejection. PMID:26689983

  16. [Medical treatment of lymphatic filariasis].

    PubMed

    Hovette, P; Laroche, R; Verrot, D; Molinier, S; Touze, J E

    1991-01-01

    Lymphatic filariasis remains in 1991 a major health problem. Ivermectine revolutionizes their treatment and, by suppressing microfilaremia, provides a new method of helping to control the vector-borne transmission of lymphatic filariasis. PMID:2072855

  17. Downregulation of FoxC2 Increased Susceptibility to Experimental Colitis: Influence of Lymphatic Drainage Function?

    PubMed Central

    Becker, Felix; Potepalov, Sergey; Shehzahdi, Romana; Bernas, Michael; Witte, Marlys; Abreo, Fleurette; Traylor, James; Orr, Wayne A.; Tsunoda, Ikuo

    2015-01-01

    Background: Although inflammation-induced expansion of the intestinal lymphatic vasculature (lymphangiogenesis) is known to be a crucial event in limiting inflammatory processes, through clearance of interstitial fluid and immune cells, considerably less is known about the impact of an impaired lymphatic clearance function (as seen in inflammatory bowel diseases) on this cascade. We aimed to investigate whether the impaired intestinal lymphatic drainage function observed in FoxC2(+/−) mice would influence the course of disease in a model of experimental colitis. Methods: Acute dextran sodium sulfate colitis was induced in wild-type and haploinsufficient FoxC2(+/−) mice, and survival, disease activity, colonic histopathological injury, neutrophil, T-cell, and macrophage infiltration were evaluated. Functional and structural changes in the intestinal lymphatic vessel network were analyzed, including submucosal edema, vessel morphology, and lymphatic vessel density. Results: We found that FoxC2 downregulation in FoxC2(+/−) mice significantly increased the severity and susceptibility to experimental colitis, as displayed by lower survival rates, increased disease activity, greater histopathological injury, and elevated colonic neutrophil, T-cell, and macrophage infiltration. These findings were accompanied by structural (dilated torturous lymphatic vessels) and functional (greater submucosal edema, higher immune cell burden) changes in the intestinal lymphatic vasculature. Conclusions: These results indicate that sufficient lymphatic clearance plays a crucial role in limiting the initiation and perpetuation of experimental colitis and those disturbances in the integrity of the intestinal lymphatic vessel network could intensify intestinal inflammation. Future therapies might be able to exploit these processes to restore and maintain adequate lymphatic clearance function in inflammatory bowel disease. PMID:25822012

  18. Exploring local immune responses to vaccines using efferent lymphatic cannulation.

    PubMed

    Mahakapuge, Thilini An; Every, Alison L; Scheerlinck, Jean-Pierre Y

    2015-04-01

    The early stages of the induction of a primary immune response to a vaccine can shape the overall quality of the immune memory generated and hence affect the success of the vaccine. This early interaction between a vaccine and the immune system occurs first at the site of vaccination and can be explored using afferent cannulation. Subsequently, the vaccine and adjuvant activates the local draining lymph node. These interactions can be studied in real time in vivo using efferent lymphatic duct cannulation in large animal models and are the subject of this review. Depending on how the vaccine is delivered, the draining lymph nodes of different organs can be accessed, facilitating the testing of tissue-specific vaccinations. The efferent lymphatic cannulation model provides an avenue to study the effect of both adjuvants and antigen on the local immune system, and hence opens a pathway toward developing more effective ways of inducing immunity.

  19. The role of the lymphatic system in endometriosis: a comprehensive review of the literature.

    PubMed

    Jerman, Laila F; Hey-Cunningham, Alison J

    2015-03-01

    Endometriosis is a benign gynecological disorder characterized by the presence of tissue resembling the endometrium in locations outside the uterus. The pathogenesis of endometriosis is still unknown; however, it is believed that the lymphatic system plays major roles in the development and progression of the disease. The lymphatic dissemination theory has been proposed to explain the presence of endometrial and/or endometriotic tissue in lymphatic vessels, lymph nodes, and rare sites, as well as high reoccurrence rates following treatment. Despite the importance of the lymphatic system in many aspects of endometriosis, there has been no previous thorough scientific update on its role in the disease. A review of scientific literature on the lymphatic system, lymphangiogenesis, and immunological changes associated with endometriosis was conducted. Lymphangiogenic potential is disturbed and lymphatic vessel density increased in the eutopic endometrium of women with endometriosis, likely promoting the entry of endometrial tissues into the lymphatic circulation. Endometriotic lesions and endometrial-like cells are present in uterine-draining nodes and various other pelvic lymph nodes. Immune responses are impaired in uterine-draining nodes, likely favoring the survival of endometrial cells and lesion establishment. In addition, lymphangiogenesis in endometriotic lesions may contribute to lesion growth and persistence, and promote the spread of endometrial cells to draining lymph nodes. The evidence reviewed in this paper supports the theory of lymphatic dissemination of endometriosis and highlights the roles of the lymphatic system in the pathogenesis and persistence of endometriosis. Understanding these roles is crucial for establishment of novel therapeutic approaches.

  20. Vegfc Regulates Bipotential Precursor Division and Prox1 Expression to Promote Lymphatic Identity in Zebrafish.

    PubMed

    Koltowska, Katarzyna; Lagendijk, Anne Karine; Pichol-Thievend, Cathy; Fischer, Johanna C; Francois, Mathias; Ober, Elke A; Yap, Alpha S; Hogan, Benjamin M

    2015-12-01

    Lymphatic vessels arise chiefly from preexisting embryonic veins. Genetic regulators of lymphatic fate are known, but how dynamic cellular changes contribute during the acquisition of lymphatic identity is not understood. We report the visualization of zebrafish lymphatic precursor cell dynamics during fate restriction. In the cardinal vein, cellular commitment is linked with the division of bipotential Prox1-positive precursor cells, which occurs immediately prior to sprouting angiogenesis. Following precursor division, identities are established asymmetrically in daughter cells; one daughter cell becomes lymphatic and progressively upregulates Prox1, and the other downregulates Prox1 and remains in the vein. Vegfc drives cell division and Prox1 expression in lymphatic daughter cells, coupling signaling dynamics with daughter cell fate restriction and precursor division. PMID:26655899

  1. Lymphatics in Neurological Disorders: A Neuro-Lympho-Vascular Component of Multiple Sclerosis and Alzheimer's Disease?

    PubMed

    Louveau, Antoine; Da Mesquita, Sandro; Kipnis, Jonathan

    2016-09-01

    Lymphatic vasculature drains interstitial fluids, which contain the tissue's waste products, and ensures immune surveillance of the tissues, allowing immune cell recirculation. Until recently, the CNS was considered to be devoid of a conventional lymphatic vasculature. The recent discovery in the meninges of a lymphatic network that drains the CNS calls into question classic models for the drainage of macromolecules and immune cells from the CNS. In the context of neurological disorders, the presence of a lymphatic system draining the CNS potentially offers a new player and a new avenue for therapy. In this review, we will attempt to integrate the known primary functions of the tissue lymphatic vasculature that exists in peripheral organs with the proposed function of meningeal lymphatic vessels in neurological disorders, specifically multiple sclerosis and Alzheimer's disease. We propose that these (and potentially other) neurological afflictions can be viewed as diseases with a neuro-lympho-vascular component and should be therapeutically targeted as such. PMID:27608759

  2. The meningeal lymphatic system: a route for HIV brain migration?

    PubMed

    Lamers, Susanna L; Rose, Rebecca; Ndhlovu, Lishomwa C; Nolan, David J; Salemi, Marco; Maidji, Ekaterina; Stoddart, Cheryl A; McGrath, Michael S

    2016-06-01

    Two innovative studies recently identified functional lymphatic structures in the meninges that may influence the development of HIV-associated neurological disorders (HAND). Until now, blood vessels were assumed to be the sole transport system by which HIV-infected monocytes entered the brain by bypassing a potentially hostile blood-brain barrier through inflammatory-mediated semi-permeability. A cascade of specific chemokine signals promote monocyte migration from blood vessels to surrounding brain tissues via a well-supported endothelium, where the cells differentiate into tissue macrophages capable of productive HIV infection. Lymphatic vessels on the other hand are more loosely organized than blood vessels. They absorb interstitial fluid from bodily tissues where HIV may persist and exchange a variety of immune cells (CD4(+) T cells, monocytes, macrophages, and dendritic cells) with surrounding tissues through discontinuous endothelial junctions. We propose that the newly discovered meningeal lymphatics are key to HIV migration among viral reservoirs and brain tissue during periods of undetectable plasma viral loads due to suppressive combinational antiretroviral therapy, thus redefining the migration process in terms of a blood-lymphatic transport system.

  3. Essential role of the coxsackie- and adenovirus receptor (CAR) in development of the lymphatic system in mice.

    PubMed

    Mirza, Momina; Pang, Mei-Fong; Zaini, Mohamad Amr; Haiko, Paula; Tammela, Tuomas; Alitalo, Kari; Philipson, Lennart; Fuxe, Jonas; Sollerbrant, Kerstin

    2012-01-01

    The coxsackie- and adenovirus receptor (CAR) is a cell adhesion molecule predominantly associated with epithelial tight junctions in adult tissues. CAR is also expressed in cardiomyocytes and essential for heart development up to embryonic day 11.5, but not thereafter. CAR is not expressed in vascular endothelial cells but was recently detected in neonatal lymphatic vessels, suggesting that CAR could play a role in the development of the lymphatic system. To address this, we generated mice carrying a conditional deletion of the CAR gene (Cxadr) and knocked out CAR in the mouse embryo at different time points during post-cardiac development. Deletion of Cxadr from E12.5, but not from E13.5, resulted in subcutaneous edema, hemorrhage and embryonic death. Subcutaneous lymphatic vessels were dilated and structurally abnormal with gaps and holes present at lymphatic endothelial cell-cell junctions. Furthermore, lymphatic vessels were filled with erythrocytes showing a defect in the separation between the blood and lymphatic systems. Regionally, erythrocytes leaked out into the interstitium from leaky lymphatic vessels explaining the hemorrhage detected in CAR-deficient mouse embryos. The results show that CAR plays an essential role in development of the lymphatic vasculature in the mouse embryo by promoting appropriate formation of lymphatic endothelial cell-cell junctions.

  4. Role of CD11b+ Macrophages in Intraperitoneal Lipopolysaccharide-Induced Aberrant Lymphangiogenesis and Lymphatic Function in the Diaphragm

    PubMed Central

    Kim, Kyung Eun; Koh, Young-Jun; Jeon, Bong-Hyun; Jang, Cholsoon; Han, Jinah; Kataru, Raghu P.; Schwendener, Reto A.; Kim, Jin-Man; Koh, Gou Young

    2009-01-01

    Lymphatic vessels in the diaphragm are essential for draining peritoneal fluid, but little is known about their pathological changes during inflammation. Here we characterized diaphragmatic lymphatic vessels in a peritonitis model generated by daily i.p. administration of lipopolysaccharide (LPS) in mice. Intraperitoneal LPS increased lymphatic density, branching, sprouts, connections, and network formation in the diaphragm in time- and dose-dependent manners. These changes were reversible on discontinuation of LPS administration. The LPS-induced lymphatic density and remodeling occur mainly through proliferation of lymphatic endothelial cells. CD11b+ macrophages were massively accumulated and closely associated with the lymphatic vessels changed by i.p. LPS. Both RT-PCR assays and experiments with vascular endothelial growth factor-C/D blockade and macrophage-depletion indicated that the CD11b+ macrophage-derived lymphangiogenic factors vascular endothelial growth factor-C/D could be major mediators of LPS-induced lymphangiogenesis and lymphatic remodeling through paracrine activity. Functional assays with India ink and fluorescein isothiocyanate-microspheres indicated that impaired peritoneal fluid drainage in diaphragm of LPS-induced peritonitis mice was due to inflammatory fibrosis and massive attachment of CD11b+ macrophages on the peritoneal side of the diaphragmatic lymphatic vessels. These findings reveal that CD11b+ macrophages play an important role in i.p. LPS-induced aberrant lymphangiogenesis and lymphatic dysfunction in the diaphragm. PMID:19762711

  5. Measurement of cytosolic Ca2+ in isolated contractile lymphatics.

    PubMed

    Souza-Smith, Flavia M; Kurtz, Kristine M; Breslin, Jerome W

    2011-01-01

    Lymphatic vessels comprise a multifunctional transport system that maintains fluid homeostasis, delivers lipids to the central circulation, and acts as a surveillance system for potentially harmful antigens, optimizing mucosal immunity and adaptive immune responses. Lymph is formed from interstitial fluid that enters blind-ended initial lymphatics, and then is transported against a pressure gradient in larger collecting lymphatics. Each collecting lymphatic is made up of a series of segments called lymphangions, separated by bicuspid valves that prevent backflow. Each lymphangion possesses a contractile cycle that propels lymph against a pressure gradient toward the central circulation. This phasic contractile pattern is analogous to the cardiac cycle, with systolic and diastolic phases, and with a lower contraction frequency. In addition, lymphatic smooth muscle generates tone and displays myogenic constriction and dilation in response to increases and decreases in luminal pressure, respectively. A hybrid of molecular mechanisms that support both the phasic and tonic contractility of lymphatics are thus proposed. Contraction of smooth muscle is generally regulated by the cytosolic Ca(2+) concentration ([Ca(2+)](i)) plus sensitivity to Ca(2+) of the contractile elements in response to changes in the environment surrounding the cell. [Ca(2+)](i) is determined by the combination of the movement of Ca(2+) through plasma membrane ligand or voltage gated Ca(2+) channels and the release and uptake of Ca(2+) from internal stores. Cytosolic Ca(2+) binds to calmodulin and activates enzymes such as myosin light chain (MLC) kinase (MLCK), which in turn phosphorylates MLC leading to actin-myosin-mediated contraction. However, the sensitivity of this pathway to Ca(2+) can be regulated by the MLC phosphatase (MLCP). MLCP activity is regulated by Rho kinase (ROCK) and the myosin phosphatase inhibitor protein CPI-17. Here, we present a method to evaluate changes in [Ca(2+)](i

  6. A dural lymphatic vascular system that drains brain interstitial fluid and macromolecules.

    PubMed

    Aspelund, Aleksanteri; Antila, Salli; Proulx, Steven T; Karlsen, Tine Veronica; Karaman, Sinem; Detmar, Michael; Wiig, Helge; Alitalo, Kari

    2015-06-29

    The central nervous system (CNS) is considered an organ devoid of lymphatic vasculature. Yet, part of the cerebrospinal fluid (CSF) drains into the cervical lymph nodes (LNs). The mechanism of CSF entry into the LNs has been unclear. Here we report the surprising finding of a lymphatic vessel network in the dura mater of the mouse brain. We show that dural lymphatic vessels absorb CSF from the adjacent subarachnoid space and brain interstitial fluid (ISF) via the glymphatic system. Dural lymphatic vessels transport fluid into deep cervical LNs (dcLNs) via foramina at the base of the skull. In a transgenic mouse model expressing a VEGF-C/D trap and displaying complete aplasia of the dural lymphatic vessels, macromolecule clearance from the brain was attenuated and transport from the subarachnoid space into dcLNs was abrogated. Surprisingly, brain ISF pressure and water content were unaffected. Overall, these findings indicate that the mechanism of CSF flow into the dcLNs is directly via an adjacent dural lymphatic network, which may be important for the clearance of macromolecules from the brain. Importantly, these results call for a reexamination of the role of the lymphatic system in CNS physiology and disease.

  7. A dural lymphatic vascular system that drains brain interstitial fluid and macromolecules

    PubMed Central

    Aspelund, Aleksanteri; Antila, Salli; Proulx, Steven T.; Karlsen, Tine Veronica; Karaman, Sinem; Detmar, Michael; Wiig, Helge

    2015-01-01

    The central nervous system (CNS) is considered an organ devoid of lymphatic vasculature. Yet, part of the cerebrospinal fluid (CSF) drains into the cervical lymph nodes (LNs). The mechanism of CSF entry into the LNs has been unclear. Here we report the surprising finding of a lymphatic vessel network in the dura mater of the mouse brain. We show that dural lymphatic vessels absorb CSF from the adjacent subarachnoid space and brain interstitial fluid (ISF) via the glymphatic system. Dural lymphatic vessels transport fluid into deep cervical LNs (dcLNs) via foramina at the base of the skull. In a transgenic mouse model expressing a VEGF-C/D trap and displaying complete aplasia of the dural lymphatic vessels, macromolecule clearance from the brain was attenuated and transport from the subarachnoid space into dcLNs was abrogated. Surprisingly, brain ISF pressure and water content were unaffected. Overall, these findings indicate that the mechanism of CSF flow into the dcLNs is directly via an adjacent dural lymphatic network, which may be important for the clearance of macromolecules from the brain. Importantly, these results call for a reexamination of the role of the lymphatic system in CNS physiology and disease. PMID:26077718

  8. The surgical anatomy of the lymphatic system of the pancreas.

    PubMed

    Cesmebasi, Alper; Malefant, Jason; Patel, Swetal D; Du Plessis, Maira; Renna, Sarah; Tubbs, R Shane; Loukas, Marios

    2015-05-01

    The lymphatic system of the pancreas is a complex, intricate network of lymphatic vessels and nodes responsible for the drainage of the head, neck, body, and tail of the pancreas. Its anatomical divisions and embryological development have been well described in the literature with emphasis on its clinical relevance in regards to pancreatic pathologies. A thorough knowledge and understanding of the lymphatic system surrounding the pancreas is critical for physicians in providing diagnostic and treatment strategies for patients with pancreatic cancer and pancreatitis. Pancreatic cancer has an extremely poor prognosis and is a notable cause of morbidity and mortality worldwide. Although a surgeon may try to predict the routes for metastasis for pancreatic cancer, the complexity of this system presents difficulty due to variable drainage patterns. Pancreatitis also presents as another severe disease which has been shown to have an association with the lymphatics. The aim of this article is to review the literature on the lymphatics of the pancreas, pancreatic pathologies, and the available imaging methodologies used to study the pancreatic lymphatics.

  9. Lymphatic function is required prenatally for lung inflation at birth

    PubMed Central

    Jakus, Zoltán; Gleghorn, Jason P.; Enis, David R.; Sen, Aslihan; Chia, Stephanie; Liu, Xi; Rawnsley, David R.; Yang, Yiqing; Hess, Paul R.; Zou, Zhiying; Yang, Jisheng; Guttentag, Susan H.; Nelson, Celeste M.

    2014-01-01

    Mammals must inflate their lungs and breathe within minutes of birth to survive. A key regulator of neonatal lung inflation is pulmonary surfactant, a lipoprotein complex which increases lung compliance by reducing alveolar surface tension (Morgan, 1971). Whether other developmental processes also alter lung mechanics in preparation for birth is unknown. We identify prenatal lymphatic function as an unexpected requirement for neonatal lung inflation and respiration. Mice lacking lymphatic vessels, due either to loss of the lymphangiogenic factor CCBE1 or VEGFR3 function, appear cyanotic and die shortly after birth due to failure of lung inflation. Failure of lung inflation is not due to reduced surfactant levels or altered development of the lung but is associated with an elevated wet/dry ratio consistent with edema. Embryonic studies reveal active lymphatic function in the late gestation lung, and significantly reduced total lung compliance in late gestation embryos that lack lymphatics. These findings reveal that lymphatic vascular function plays a previously unrecognized mechanical role in the developing lung that prepares it for inflation at birth. They explain respiratory failure in infants with congenital pulmonary lymphangiectasia, and suggest that inadequate late gestation lymphatic function may also contribute to respiratory failure in premature infants. PMID:24733830

  10. Lymphatics at the crossroads of angiogenesis and lymphangiogenesis

    PubMed Central

    Scavelli, Claudio; Weber, Elisabetta; Aglianò, Margherita; Cirulli, Teresa; Nico, Beatrice; Vacca, Angelo; Ribatti, Domenico

    2004-01-01

    The lymphatic system is implicated in interstitial fluid balance regulation, immune cell trafficking, oedema and cancer metastasis. However, the sequence of events that initiate and coordinate lymphatic vessel development (lymphangiogenesis) remains obscure. In effect, the understanding of physiological regulation of lymphatic vasculature has been overshadowed by the greater emphasis focused on angiogenesis, and delayed by a lack of specific markers, thereby limiting this field to no more than a descriptive characterization. Recently, new insights into lymphangiogenesis research have been due to the discovery of lymphatic-specific markers and growth factors of vascular endothelial growth factor (VEGF) family, such as VEGF-C and VEGF-D. Studies using transgenic mice overexpressing VEGF-C and VEGF-D have demonstrated a crucial role for these factors in tumour lymphangiogenesis. Knowledge of lymphatic development has now been redefined at the molecular level, providing an interesting target for innovative therapies. This review highlights the recent insights and advances into the field of lymphatic vascular research, outlining the most important aspects of the embryo development, structure, specific markers and methods applied for studying lymphangiogenesis. Finally, molecular mechanisms involved in the regulation of lymphangiogenesis are described. PMID:15198686

  11. Potential application of in vivo imaging of impaired lymphatic duct to evaluate the severity of pressure ulcer in mouse model

    NASA Astrophysics Data System (ADS)

    Kasuya, Akira; Sakabe, Jun-Ichi; Tokura, Yoshiki

    2014-02-01

    Ischemia-reperfusion (IR) injury is a cause of pressure ulcer. However, a mechanism underlying the IR injury-induced lymphatic vessel damage remains unclear. We investigated the alterations of structure and function of lymphatic ducts in a mouse cutaneous IR model. And we suggested a new method for evaluating the severity of pressure ulcer. Immunohistochemistry showed that lymphatic ducts were totally vanished by IR injury, while blood vessels were relatively preserved. The production of harmful reactive oxygen species (ROS) was increased in injured tissue. In vitro study showed a high vulnerability of lymphatic endothelial cells to ROS. Then we evaluated the impaired lymphatic drainage using an in vivo imaging system for intradermally injected indocyanine green (ICG). The dysfunction of ICG drainage positively correlated with the severity of subsequent cutaneous changes. Quantification of the lymphatic duct dysfunction by this imaging system could be a useful strategy to estimate the severity of pressure ulcer.

  12. VEGF165 Stimulates Vessel Density and Vessel Diameter Differently in Angiogenesis and Lymphangiogenesis

    NASA Technical Reports Server (NTRS)

    Parsons-Wingerter, Patricia; Radhakrishnan, Krishnan; DiCorleto, Paul E.; Leontiev, Dmitry; Anand-Apte, Bela; Albarran, Brian; Farr, Andrew G.

    2005-01-01

    Vascular endothelial growth factor-165 (VEGF(sub 165)) stimulated angiogenesis in the quail chorioallantoic membrane (CAM) by vessel expansion from the capillary network. However, lymphangiogenesis was stimulated by the filopodial guidance of tip cells located on blind-ended lymphatic sprouts. As quantified by fractal/generational branching analysis using the computer code VESGEN, vascular density increased maximally at low VEGF concentrations, and vascular diameter increased most at high VEGF concentrations. Increased vascular density and diameter were statistically independent events (r(sub s), -0.06). By fluorescence immunohistochemistry of VEGF receptors VEGFR-1 and VEGFR-2, alpha smooth muscle actin ((alpha) SMA) and a vascular/lymphatic marker, VEGF(sub 165) increased the density and diameter of sprouting lymphatic vessels guided by tip cells (accompanied by the dissociation of lymphatics from blood vessels). Isolated migratory cells expressing (alpha)SMA were recruited to blood vessels, whereas isolated cells expressing VEGFR-2 were recruited primarily to lymphatics. In conclusion, VEGF(sub 165) increased lymphatic vessel density by lymphatic sprouting, but increased blood vessel density by vascular expansion from the capillary network.

  13. In vivo albumin labeling and lymphatic imaging.

    PubMed

    Wang, Yu; Lang, Lixin; Huang, Peng; Wang, Zhe; Jacobson, Orit; Kiesewetter, Dale O; Ali, Iqbal U; Teng, Gaojun; Niu, Gang; Chen, Xiaoyuan

    2015-01-01

    The ability to accurately and easily locate sentinel lymph nodes (LNs) with noninvasive imaging methods would assist in tumor staging and patient management. For this purpose, we developed a lymphatic imaging agent by mixing fluorine-18 aluminum fluoride-labeled NOTA (1,4,7-triazacyclononane-N,N',N''-triacetic acid)-conjugated truncated Evans blue ((18)F-AlF-NEB) and Evans blue (EB) dye. After local injection, both (18)F-AlF-NEB and EB form complexes with endogenous albumin in the interstitial fluid and allow for visualizing the lymphatic system. Positron emission tomography (PET) and/or optical imaging of LNs was performed in three different animal models including a hind limb inflammation model, an orthotropic breast cancer model, and a metastatic breast cancer model. In all three models, the LNs can be distinguished clearly by the apparent blue color and strong fluorescence signal from EB as well as a high-intensity PET signal from (18)F-AlF-NEB. The lymphatic vessels between the LNs can also be optically visualized. The easy preparation, excellent PET and optical imaging quality, and biosafety suggest that this combination of (18)F-AlF-NEB and EB has great potential for clinical application to map sentinel LNs and provide intraoperative guidance. PMID:25535368

  14. In vivo albumin labeling and lymphatic imaging

    PubMed Central

    Wang, Yu; Lang, Lixin; Huang, Peng; Wang, Zhe; Jacobson, Orit; Kiesewetter, Dale O.; Ali, Iqbal U.; Teng, Gaojun; Niu, Gang; Chen, Xiaoyuan

    2015-01-01

    The ability to accurately and easily locate sentinel lymph nodes (LNs) with noninvasive imaging methods would assist in tumor staging and patient management. For this purpose, we developed a lymphatic imaging agent by mixing fluorine-18 aluminum fluoride-labeled NOTA (1,4,7-triazacyclononane-N,N',N''-triacetic acid)-conjugated truncated Evans blue (18F-AlF-NEB) and Evans blue (EB) dye. After local injection, both 18F-AlF-NEB and EB form complexes with endogenous albumin in the interstitial fluid and allow for visualizing the lymphatic system. Positron emission tomography (PET) and/or optical imaging of LNs was performed in three different animal models including a hind limb inflammation model, an orthotropic breast cancer model, and a metastatic breast cancer model. In all three models, the LNs can be distinguished clearly by the apparent blue color and strong fluorescence signal from EB as well as a high-intensity PET signal from 18F-AlF-NEB. The lymphatic vessels between the LNs can also be optically visualized. The easy preparation, excellent PET and optical imaging quality, and biosafety suggest that this combination of 18F-AlF-NEB and EB has great potential for clinical application to map sentinel LNs and provide intraoperative guidance. PMID:25535368

  15. Nonmalignant Adult Thoracic Lymphatic Disorders.

    PubMed

    Itkin, Maxim; McCormack, Francis X

    2016-09-01

    The thoracic lymphatic disorders are a heterogeneous group of uncommon conditions that are associated with thoracic masses, interstitial pulmonary infiltrates, and chylous complications. Accurate diagnosis of the thoracic lymphatic disorders has important implications for the newest approaches to management, including embolization and treatment with antilymphangiogenic drugs. New imaging techniques to characterize lymphatic flow, such as dynamic contrast-enhanced magnetic resonance lymphangiogram, are redefining approaches to disease classification and therapy. PMID:27514588

  16. Lymphatic function in the liver after hepatic venous pressure elevation.

    PubMed

    Elk, J R; Drake, R E; Williams, J P; Gabel, J C; Laine, G A

    1988-05-01

    The liver lymphatic system plays an important role in removing excess fluid from the hepatic tissue. A complete analysis of the liver lymphatic system would be difficult. However, we used a simple circuit-analysis technique to represent the intrahepatic portion of the lymph system as a single pressure source (PL) pushing lymph through a single resistance (RL). Liver lymphatic vessels were cannulated in nine halothane-anesthetized dogs. The lymphatic vessel outflow pressure (PO) was varied by raising the outflow end of the cannula. Lymph flow from the cannula (QL) decreased linearly with PO, and we calculated RL as -delta PO/delta QL and PL as the extrapolated PO at which QL = 0. At base line, PL = 8.5 +/- 2.9 cmH2O, and RL = 0.05 +/- 0.03 cmH2O.min/microliter. After we increased inferior vena caval pressure from 5.8 +/- 2.7 to 15.2 +/- 2.5 cmH2O, PL increased significantly to 13.7 +/- 3.4 cmH2O, and RL decreased to 0.02 +/- 0.02 cmH2O.min/microliter (P less than 0.05). The results indicate that increases in QL occur because the effective pressure pushing lymph from the liver (PL) increases, and the effective resistance of the intrahepatic lymph vessels (RL) decreases.

  17. Monitoring contractile dermal lymphatic activity following uniaxial mechanical loading.

    PubMed

    Gray, R J; Worsley, P R; Voegeli, D; Bader, D L

    2016-09-01

    It is proposed that direct mechanical loading can impair dermal lymphatic function, contributing to the causal pathway of pressure ulcers. The present study aims to investigate the effects of loading on human dermal lymphatic vessels. Ten participants were recruited with ages ranging from 24 to 61 years. Participants had intradermal Indocyanine Green injections administrated between left finger digits. Fluorescence was imaged for 5min sequences with an infra-red camera prior to lymph vessel loading, immediately after axial loading (60mmHg) and following a recovery period. Image processing was employed to defined transient lymph packets and compare lymph function between each test phase. The results revealed that between 1-8 transient events (median=4) occurred at baseline, with a median velocity of 8.1mm/sec (range 4.1-20.1mm/sec). Immediately post-loading, there was a significant (p<0.05) reduction in velocity (median=6.4, range 2.2-13.5mm/sec), although the number of transient lymph packages varied between participants. During the recovery period the number (range 1-7) and velocity (recovery median=9.6mm/sec) of transient packets were largely restored to basal values. The present study revealed that some individuals present with impaired dermal lymphatic function immediately after uniaxial mechanical loading. More research is needed to investigate the effects of pressure and shear on lymphatic vessel patency. PMID:27245749

  18. Low-invasive lymphatic surgery and lymphatic imaging for completely healed intractable pudendal lymphorrhea after gynecologic cancer treatment.

    PubMed

    Mihara, Makoto; Hara, Hisako; Narushima, Mitsunaga; Mitsui, Kito; Murai, Noriyuki; Koshima, Isao

    2012-01-01

    Lower limb lymphedema and an accompanying lymphatic fistula (lymphorrhea) occur as complications after gynecologic surgery to treat cancer. Herein, we report the case of a 68-year-old woman who underwent resection and radiotherapy because of uterine cervical cancer (stage 2a) 20 years previously. Left lower limb and pudendal lymphedema and continuous lymphorrhea developed soon after surgery. Conservative treatment was administered; however, the edema increased, and a pudendal lymphatic fistula and cellulitis developed repeatedly. Lymphovascular anastomosis (LVA) and lymph vessel ligation were performed after preoperative evaluation via lymphoscintigraphy and indocyanine green (ICG) lymphography. A radioisotope injected into the first interdigit pedal region flowed into the pudendal region via the inguinal lymph nodes at preoperative lymphoscintigraphy. Linear patterns were observed up to the half level of the crus, and stardust patterns occurred over the lower abdominal and pudendal regions at ICG lymphography. During surgery, ICG lymphography was also used to identify the site of the fistula. With the patient under local anesthesia, LVA was applied in the half crus and left inguinal regions, followed by ligation and division of lymph vessels flowing into the fistula. The region around the fistula was excised as a 1 × 3-cm tissue block. As of 5 months after surgery, no recurrence of lymphatic fistula or exacerbation of lymphedema has occurred. This case shows the effectiveness of preoperative ICG lymphography and lymphoscintigraphy followed by treatment via lymph vessel ligation and LVA for curative resolution of a lymphatic fistula.

  19. Lymphatic transport of exosomes as a rapid route of information dissemination to the lymph node

    PubMed Central

    Srinivasan, Swetha; Vannberg, Fredrik O.; Dixon, J. Brandon

    2016-01-01

    It is well documented that cells secrete exosomes, which can transfer biomolecules that impact recipient cells’ functionality in a variety of physiologic and disease processes. The role of lymphatic drainage and transport of exosomes is as yet unknown, although the lymphatics play critical roles in immunity and exosomes are in the ideal size-range for lymphatic transport. Through in vivo near-infrared (NIR) imaging we have shown that exosomes are rapidly transported within minutes from the periphery to the lymph node by lymphatics. Using an in vitro model of lymphatic uptake, we have shown that lymphatic endothelial cells actively enhanced lymphatic uptake and transport of exosomes to the luminal side of the vessel. Furthermore, we have demonstrated a differential distribution of exosomes in the draining lymph nodes that is dependent on the lymphatic flow. Lastly, through endpoint analysis of cellular distribution of exosomes in the node, we identified macrophages and B-cells as key players in exosome uptake. Together these results suggest that exosome transfer by lymphatic flow from the periphery to the lymph node could provide a mechanism for rapid exchange of infection-specific information that precedes the arrival of migrating cells, thus priming the node for a more effective immune response. PMID:27087234

  20. Expression of Lymphatic Markers in the Adult Rat Spinal Cord

    PubMed Central

    Kaser-Eichberger, Alexandra; Schroedl, Falk; Bieler, Lara; Trost, Andrea; Bogner, Barbara; Runge, Christian; Tempfer, Herbert; Zaunmair, Pia; Kreutzer, Christina; Traweger, Andreas; Reitsamer, Herbert A.; Couillard-Despres, Sebastien

    2016-01-01

    Under physiological conditions, lymphatic vessels are thought to be absent from the central nervous system (CNS), although they are widely distributed within the rest of the body. Recent work in the eye, i.e., another organ regarded as alymphatic, revealed numerous cells expressing lymphatic markers. As the latter can be involved in the response to pathological conditions, we addressed the presence of cells expressing lymphatic markers within the spinal cord by immunohistochemistry. Spinal cord of young adult Fisher rats was scrutinized for the co-expression of the lymphatic markers PROX1 and LYVE-1 with the cell type markers Iba1, CD68, PGP9.5, OLIG2. Rat skin served as positive control for the lymphatic markers. PROX1-immunoreactivity was detected in many nuclei throughout the spinal cord white and gray matter. These nuclei showed no association with LYVE-1. Expression of LYVE-1 could only be detected in cells at the spinal cord surface and in cells closely associated with blood vessels. These cells were found to co-express Iba1, a macrophage and microglia marker. Further, double labeling experiments using CD68, another marker found in microglia and macrophages, also displayed co-localization in the Iba1+ cells located at the spinal cord surface and those apposed to blood vessels. On the other hand, PROX1-expressing cells found in the parenchyma were lacking Iba1 or PGP9.5, but a significant fraction of those cells showed co-expression of the oligodendrocyte lineage marker OLIG2. Intriguingly, following spinal cord injury, LYVE-1-expressing cells assembled and reorganized into putative pre-vessel structures. As expected, the rat skin used as positive controls revealed classical lymphatic vessels, displaying PROX1+ nuclei surrounded by LYVE-1-immunoreactivity. Classical lymphatics were not detected in adult rat spinal cord. Nevertheless, numerous cells expressing either LYVE-1 or PROX1 were identified. Based on their localization and overlapping expression with

  1. Expression of Lymphatic Markers in the Adult Rat Spinal Cord.

    PubMed

    Kaser-Eichberger, Alexandra; Schroedl, Falk; Bieler, Lara; Trost, Andrea; Bogner, Barbara; Runge, Christian; Tempfer, Herbert; Zaunmair, Pia; Kreutzer, Christina; Traweger, Andreas; Reitsamer, Herbert A; Couillard-Despres, Sebastien

    2016-01-01

    Under physiological conditions, lymphatic vessels are thought to be absent from the central nervous system (CNS), although they are widely distributed within the rest of the body. Recent work in the eye, i.e., another organ regarded as alymphatic, revealed numerous cells expressing lymphatic markers. As the latter can be involved in the response to pathological conditions, we addressed the presence of cells expressing lymphatic markers within the spinal cord by immunohistochemistry. Spinal cord of young adult Fisher rats was scrutinized for the co-expression of the lymphatic markers PROX1 and LYVE-1 with the cell type markers Iba1, CD68, PGP9.5, OLIG2. Rat skin served as positive control for the lymphatic markers. PROX1-immunoreactivity was detected in many nuclei throughout the spinal cord white and gray matter. These nuclei showed no association with LYVE-1. Expression of LYVE-1 could only be detected in cells at the spinal cord surface and in cells closely associated with blood vessels. These cells were found to co-express Iba1, a macrophage and microglia marker. Further, double labeling experiments using CD68, another marker found in microglia and macrophages, also displayed co-localization in the Iba1+ cells located at the spinal cord surface and those apposed to blood vessels. On the other hand, PROX1-expressing cells found in the parenchyma were lacking Iba1 or PGP9.5, but a significant fraction of those cells showed co-expression of the oligodendrocyte lineage marker OLIG2. Intriguingly, following spinal cord injury, LYVE-1-expressing cells assembled and reorganized into putative pre-vessel structures. As expected, the rat skin used as positive controls revealed classical lymphatic vessels, displaying PROX1+ nuclei surrounded by LYVE-1-immunoreactivity. Classical lymphatics were not detected in adult rat spinal cord. Nevertheless, numerous cells expressing either LYVE-1 or PROX1 were identified. Based on their localization and overlapping expression with

  2. Cell-based approach for 3D reconstruction of lymphatic capillaries in vitro reveals distinct functions of HGF and VEGF-C in lymphangiogenesis.

    PubMed

    Gibot, Laure; Galbraith, Todd; Kloos, Bryan; Das, Suvendu; Lacroix, Dan A; Auger, François A; Skobe, Mihaela

    2016-02-01

    Regeneration of lymphatic vessels is important for treatment of various disorders of lymphatic system and for restoration of lymphatic function after surgery. We have developed a method for generating a human 3D lymphatic vascular construct. In this system, human lymphatic endothelial cells, co-cultured with fibroblasts, spontaneously organized into a stable 3D lymphatic capillary network without the use of any exogenous factors. In vitro-generated lymphatic capillaries exhibited the major molecular and ultra-structural features of native, human lymphatic microvasculature: branches in the three dimensions, wide lumen, blind ends, overlapping borders, adherens and tight junctions, anchoring filaments, lack of mural cells, and poorly developed basement membrane. Furthermore, we show that fibroblast-derived VEGF-C and HGF cooperate in the formation of lymphatic vasculature by activating ERK1/2 signaling, and demonstrate distinct functions of HGF/c-Met and VEGF-C/VEGFR-3 in lymphangiogenesis. This lymphatic vascular construct is expected to facilitate studies of lymphangiogenesis in vitro and it holds promise as a strategy for regeneration of lymphatic vessels and treatment of lymphatic disorders in various conditions.

  3. Blocking development of a CD8+ T cell response by targeting lymphatic recruitment of APC.

    PubMed

    Teoh, Denise; Johnson, Louise A; Hanke, Tomas; McMichael, Andrew J; Jackson, David G

    2009-02-15

    Generating a protective immune response to viral infection is known to depend upon the priming and clonal expansion of virus-specific CD8(+) T cells by Ag-loaded dendritic cells (DC) within secondary lymphoid tissue. However, the actual initiation of the response involves critical upstream events that control the recruitment of mature Ag-charged DC from the periphery via afferent lymphatics, events that are still only partly understood. Recent evidence has revealed that transmigration of lymphatic endothelium by DC is regulated by the adhesion molecules ICAM-1 and VCAM-1 both in vitro and in vivo. These findings imply that lymphatic entry may be an important rate-limiting step in primary immunity and a possible target for immune intervention. In this study, we have explored such possibilities using an F(5) TCR-transgenic mouse model to assess the contribution of lymphatic cell adhesion molecules in the CD8(+) T cell response to influenza virus nucleoprotein (NP). We show for the first time that immunization with ICAM-1- and VCAM-1-blocking mAbs can impair the T cell response in lymph node-draining sites of dermally administered nucleoprotein vaccine (MVA.HIVA.NP) by targeting lymphatic uptake of Ag-loaded DC ahead of other cell adhesion molecule-dependent events. These results reveal lymphatic entry as an important step that may be rate limiting in the development of immunity and reconfirm its potential as a target for localized immunotherapy in inflammation and tissue rejection.

  4. Cutaneous lymphatic sporotrichosis.

    PubMed

    Anandi, V; Kurien, T; Jacob, M; Koshi, G

    1994-01-01

    The first case of cutaneous lymphatic sporotrichosis from Nagaland and a case of cutaneous sporotrichosis from Kerala who had acquired infection from Assam are reported. The diagnosis in both cases were established by isolating Sporothrix schenckii from multiple cutaneous lesions. The dimorphic nature of fungus was established in vitro by demonstrating the mycelial phase at 25-30 degrees C and yeast phase at 37 degrees C and pathogenicity to white mice. Both the patients were successfully treated with oral administration of potassium iodide for 3 months. PMID:8088907

  5. Chronic lower limb wounds evoke systemic response of the lymphatic (immune) system

    PubMed Central

    Olszewski, W. L.; Jain, P.; Zaleska, M.; Stelmach, E.; Swoboda, E.

    2012-01-01

    Wound healing should not be considered as a process limited only to the damaged tissues. It is always accompanied by an intensive local immune response and in advanced stages, the systemic lymphatic (immune) structure. In this review we present evidence from our own studies as well as pertinent literature on the role of skin and subcutaneous tissue lymphatics at the wound site and of transport of antigens along with collecting afferent lymphatics to the lymph nodes. We also speculate the role of lymph nodes in raising cohorts of bacterial and own tissue antigen-specific lymphocytes and their participation in healing and not infrequently evoking uncontrolled chronic immune reaction causing a delay of healing. It is also speculated as to why there is a rapid response of lymph node cells to microbial antigens and tolerance to damaged-tissue-derived antigens occurs PMID:23162224

  6. Lymphangiogenesis by blind-ended vessel sprouting is concurrent with hemangiogenesis by vascular splitting.

    PubMed

    Parsons-Wingerter, Patricia; McKay, Terri L; Leontiev, Dmitry; Vickerman, Mary B; Condrich, Terence K; Dicorleto, Paul E

    2006-03-01

    Development of effective vascular therapies requires the understanding of all modes of vessel formation involved in angiogenesis (here termed "hemangiogenesis") and lymphangiogenesis. Two major modes of vessel morphogenesis include sprouting of a new vessel from a preexisting vessel and splitting of a preexisting parent vessel into two offspring vessels. In the quail chorioallantoic membrane (CAM) during mid-development (embryonic days E6-E9), lymphangiogenesis progressed primarily via blind-ended vessel sprouting. Isolated lymphatic endothelial progenitor cells were recruited to the tips of growing vessels. During concurrent hemangiogenesis, parent blood vessels expanded from the capillary network and split into offspring vessels, accompanied by transient capillary expression of alpha smooth muscle actin (alphaSMA) and recruitment of polarized mural progenitor cells. Lymphatics and blood vessels were identified by confocal/fluorescence microscopy of vascular endothelial growth factor (VEGF) receptor VEGFR-2, alphaSMA (specific to CAM blood vessels), homeobox transcription factor Prox1 (specific to lymphatics), and the quail hematopoetic marker, QH-1. VEGFR-2 was expressed intensely in isolated cells and lymphatics, and moderately in blood vessels. Prox1 was absent from isolated progenitor cells prior to lymphatic recruitment. Exogenous vascular endothelial growth factor-165 (VEGF165) increased blood vessel density and anastomotic frequency without changing endogenous modes of vascular/lymphatic vessel formation or marker expression. Although VEGF165 is a key cellular regulator of hemangiogenesis and vasculogenesis, the role of VEGF165 in lymphangiogenesis is less clear. Interestingly, VEGF165 increased lymphatic vessel diameter and density as measured by novel Euclidean distance mapping, and the antimaturational dissociation of lymphatics from blood vessels, accompanied by lymphatic reassociation into homogeneous networks.

  7. Use of a PEG-conjugated bright near-infrared dye for functional imaging of rerouting of tumor lymphatic drainage after sentinel lymph node metastasis

    PubMed Central

    Proulx, Steven T.; Luciani, Paola; Christiansen, Ailsa; Karaman, Sinem; Blum, Katrin S.; Rinderknecht, Matthias; Leroux, Jean-Christophe; Detmar, Michael

    2013-01-01

    Tumor lymphangiogenesis promotes metastatic cancer spread to lymph nodes and beyond. However, the potential remodeling and functionality of tumor-draining lymphatic vessels has remained unclear. Thus, we aimed to develop non-invasive imaging methods for repeated quantitative imaging of lymphatic drainage and of contractile collecting lymphatic vessel function in mice, with colloidal near-infrared (NIR) tracers and a custom fluorescence stereomicroscope specially adapted for NIR sensitive imaging. Using these tools, we quantitatively determined pulse rates and valvular function of collecting lymphatic vessels with high resolution. Unexpectedly, we found that tumor-draining lymphatic vessels in a melanoma footpad model initially were dilated but remained functional, despite lower pulse rates. In two independent tumor models, impaired lymphatic function was detected once metastases were present in draining lymph nodes. Importantly, we found that lymphatic dysfunction, induced by metastatic tumor spread to sentinel lymph nodes, can lead to a rerouting of lymphatic flow away from the metastatic lymph node, via collateral lymphatic vessels, to alternate lymph nodes. These findings might have important clinical implications for the procedure of sentinel lymph node mapping that represents the standard of care for determining prognosis and treatment of melanoma and breast cancer patients. PMID:23566803

  8. Utricular afferents: morphology of peripheral terminals

    PubMed Central

    Huwe, J. A.; Logan, G. J.; Williams, B.; Rowe, M. H.

    2015-01-01

    The utricle provides critical information about spatiotemporal properties of head movement. It comprises multiple subdivisions whose functional roles are poorly understood. We previously identified four subdivisions in turtle utricle, based on hair bundle structure and mechanics, otoconial membrane structure and hair bundle coupling, and immunoreactivity to calcium-binding proteins. Here we ask whether these macular subdivisions are innervated by distinctive populations of afferents to help us understand the role each subdivision plays in signaling head movements. We quantified the morphology of 173 afferents and identified six afferent classes, which differ in structure and macular locus. Calyceal and dimorphic afferents innervate one striolar band. Bouton afferents innervate a second striolar band; they have elongated terminals and the thickest processes and axons of all bouton units. Bouton afferents in lateral (LES) and medial (MES) extrastriolae have small-diameter axons but differ in collecting area, bouton number, and hair cell contacts (LES >> MES). A fourth, distinctive population of bouton afferents supplies the juxtastriola. These results, combined with our earlier findings on utricular hair cells and the otoconial membrane, suggest the hypotheses that MES and calyceal afferents encode head movement direction with high spatial resolution and that MES afferents are well suited to signal three-dimensional head orientation and striolar afferents to signal head movement onset. PMID:25632074

  9. Lymphatic System in Cardiovascular Medicine.

    PubMed

    Aspelund, Aleksanteri; Robciuc, Marius R; Karaman, Sinem; Makinen, Taija; Alitalo, Kari

    2016-02-01

    The mammalian circulatory system comprises both the cardiovascular system and the lymphatic system. In contrast to the blood vascular circulation, the lymphatic system forms a unidirectional transit pathway from the extracellular space to the venous system. It actively regulates tissue fluid homeostasis, absorption of gastrointestinal lipids, and trafficking of antigen-presenting cells and lymphocytes to lymphoid organs and on to the systemic circulation. The cardinal manifestation of lymphatic malfunction is lymphedema. Recent research has implicated the lymphatic system in the pathogenesis of cardiovascular diseases including obesity and metabolic disease, dyslipidemia, inflammation, atherosclerosis, hypertension, and myocardial infarction. Here, we review the most recent advances in the field of lymphatic vascular biology, with a focus on cardiovascular disease.

  10. [Lymphatic vascular system, development and lymph formation. Review].

    PubMed

    Bernaudin, J-F; Kambouchner, M; Lacave, R

    2013-04-01

    The lymphatic vascular system is widely developed among vertebrates. Lymphatic vessels provide the interstitial fluid (20% of the body weight) drainage through interstitial prelymphatic channels, capillaries, precollectors and collectors flowing into the venous blood. Endothelial cells of capillaries are overlapped and fixed to interstitial collagen and elastic fibres by anchoring filaments facilitating the fluid transfer. Precollectors and collectors have valves controlling the lymph flux direction. In addition to external mechanisms, the lymphangions of collectors have contracting muscle cells driving the flow. Lymphatic endothelial cells are routinely identified by the expression of podoplanin, LYVE-1 and VEGFR3. In the embryo, prelymphatic endothelial cells emerge from the cardinal veins and migrate into the mesenchyma forming embryonic lymphatic sacs. Prox1, Sox18 and COUP-TFII play a major role in the endothelial speciation, VEGFC as VEGFD combined to VEGFR3 in cell migration and proliferation and FoxC2 in valves development. In cancer or inflammation, various factors secreted by cancer cells and/or inflammatory cells induce a neolymphangiogenesis. Recently it has been shown that cells from the bone marrow could be potential precursors for lymphatic endothelial cells.

  11. Immunology of lymphatic filariasis.

    PubMed

    Babu, S; Nutman, T B

    2014-08-01

    The immune responses to filarial parasites encompass a complex network of innate and adaptive cells whose interaction with the parasite underlies a spectrum of clinical manifestations. The predominant immunological feature of lymphatic filariasis is an antigen-specific Th2 response and an expansion of IL-10 producing CD4(+) T cells that is accompanied by a muted Th1 response. This antigen-specific T-cell hyporesponsiveness appears to be crucial for the maintenance of the sustained, long-standing infection often with high parasite densities. While the correlates of protective immunity to lymphatic filariasis are still incompletely understood, primarily due to the lack of suitable animal models to study susceptibility, it is clear that T cells and to a certain extent B cells are required for protective immunity. Host immune responses, especially CD4(+) T-cell responses clearly play a role in mediating pathological manifestations of LF, including lymphedema, hydrocele and elephantiasis. The main underlying defect in the development of clinical pathology appears to be a failure to induce T-cell hyporesponsiveness in the face of antigenic stimulation. Finally, another intriguing feature of filarial infections is their propensity to induce bystander effects on a variety of immune responses, including responses to vaccinations, allergens and to other infectious agents. The complexity of the immune response to filarial infection therefore provides an important gateway to understanding the regulation of immune responses to chronic infections, in general.

  12. Immunology of lymphatic filariasis

    PubMed Central

    Babu, Subash; Nutman, Thomas B.

    2013-01-01

    The immune responses to filarial parasites encompass a complex network of innate and adaptive cells whose interaction with the parasite underlies a spectrum of clinical manifestations. The predominant immunological feature of lymphatic filariasis is an antigen - specific Th2 response and an expansion of IL-10 producing CD4+ T cells that is accompanied by a muted Th1 response. This antigen specific T cell hypo-responsiveness appears to be crucial for the maintenance of the sustained, long-standing infection often with high parasite densities. While the correlates of protective immunity to lymphatic filariasis are still incompletely understood, primarily due to the lack of suitable animal models to study susceptibility, it is clear that T cells and to a certain extent B cells are required for protective immunity. Host immune responses, especially CD4+ T cell responses clearly play a role in mediating pathological manifestations of LF, including lymphedema, hydrocele and elephantiasis. The main underlying defect in the development of clinical pathology appears to be a failure to induce T cell hypo-responsiveness in the face of antigenic stimulation. Finally, another intriguing feature of filarial infections is their propensity to induce bystander effects on a variety of immune responses, including responses to vaccinations, allergens and to other infectious agents. The complexity of the immune response to filarial infection therefore provides an important gateway to understanding the regulation of immune responses to chronic infections, in general. PMID:24134686

  13. Is lymphatic status related to regression of inflammation in Crohn's disease?

    PubMed Central

    Tonelli, Francesco; Giudici, Francesco; Liscia, Gadiel

    2012-01-01

    AIM: To investigate the status of the lymphatic vessels in the small bowel affected by Crohn’s disease (CD) at the moment of surgery. METHODS: During the period January 2011-June 2011, 25 consecutive patients affected by CD were operated on in our Institution. During surgery, Patent Blue V was injected subserosally and the way it spread along the subserosa of the intestinal wall, through the mesenterial layers towards the main lymphatic collectors and eventually to the lymph nodes was observed and recorded. Since some patients had been undergone strictureplasty at previous surgery, we also examined the status of intestinal lymph vessels after previous strictureplasties. The same procedure was performed in a control group of 5 patients affected by colorectal cancer. Length of lesions, caliber, maximal thickness of the diseased intestinal wall, thickness of the wall at injection site and thickness of the mesentery were evaluated at surgery. RESULTS: We observed three features after the injection of Patent Blue V in the intestinal loops: (1) Macroscopically healthy terminal ileum of patients with CD or colon cancer showed thin lymphatic vessels linearly directed toward the mesentery; (2) In mild lesions in which the intestinal wall did not reach 8 mm of thickness, we observed short, wide and tortuous lymphatic vessels directed longitudinally along the intestinal axis toward disease-free areas and then transversally toward the mesentery; and (3) Injection in the severely affected lesions, that had a thickness of the intestinal wall over 10 mm, did not show any feature of lymphatic vessels at least on the subserosal surface. There was a correlation between the thickness of the parietal wall and the severity of the lymphatic alterations. Normal lymphatic vessels were observed at previous strictureplasties in the presence of complete regression of the inflammation. CONCLUSION: Injection of Patent Blue V in the intestinal wall could help distinguish healthy tracts of the

  14. The Lymphatic Endothelial mCLCA1 Antibody Induces Proliferation and Growth of Lymph Node Lymphatic Sinuses.

    PubMed

    Jordan-Williams, Kimberly L; Ramanujam, Neela; Farr, Andrew G; Ruddell, Alanna

    2016-01-01

    Lymphocyte- and leukocyte-mediated lymph node (LN) lymphatic sinus growth (lymphangiogenesis) is involved in immune responses and in diseases including cancer and arthritis. We previously discovered a 10.1.1 Ab that recognizes the lymphatic endothelial cell (LEC) surface protein mCLCA1, which is an interacting partner for LFA1 and Mac-1 that mediates lymphocyte adhesion to LECs. Here, we show that 10.1.1 Ab treatment specifically induces LEC proliferation, and influences migration and adhesion in vitro. Functional testing by injection of mice with 10.1.1 Ab but not control hamster Abs identified rapid induction of LN LEC proliferation and extensive lymphangiogenesis within 23 h. BrdU pulse-chase analysis demonstrated incorporation of proliferating LYVE-1-positive LEC into the growing medullary lymphatic sinuses. The 10.1.1 Ab-induced LN remodeling involved coordinate increases in LECs and also blood endothelial cells, fibroblastic reticular cells, and double negative stroma, as is observed during the LN response to inflammation. 10.1.1 Ab-induced lymphangiogenesis was restricted to LNs, as mCLCA1-expressing lymphatic vessels of the jejunum and dermis were unaffected by 23 h 10.1.1 Ab treatment. These findings demonstrate that 10.1.1 Ab rapidly and specifically induces proliferation and growth of LN lymphatic sinuses and stroma, suggesting a key role of mCLCA1 in coordinating LN remodeling during immune responses. PMID:27224029

  15. The Lymphatic Endothelial mCLCA1 Antibody Induces Proliferation and Growth of Lymph Node Lymphatic Sinuses

    PubMed Central

    Jordan-Williams, Kimberly L.; Ramanujam, Neela; Farr, Andrew G.

    2016-01-01

    Lymphocyte- and leukocyte-mediated lymph node (LN) lymphatic sinus growth (lymphangiogenesis) is involved in immune responses and in diseases including cancer and arthritis. We previously discovered a 10.1.1 Ab that recognizes the lymphatic endothelial cell (LEC) surface protein mCLCA1, which is an interacting partner for LFA1 and Mac-1 that mediates lymphocyte adhesion to LECs. Here, we show that 10.1.1 Ab treatment specifically induces LEC proliferation, and influences migration and adhesion in vitro. Functional testing by injection of mice with 10.1.1 Ab but not control hamster Abs identified rapid induction of LN LEC proliferation and extensive lymphangiogenesis within 23 h. BrdU pulse-chase analysis demonstrated incorporation of proliferating LYVE-1-positive LEC into the growing medullary lymphatic sinuses. The 10.1.1 Ab-induced LN remodeling involved coordinate increases in LECs and also blood endothelial cells, fibroblastic reticular cells, and double negative stroma, as is observed during the LN response to inflammation. 10.1.1 Ab-induced lymphangiogenesis was restricted to LNs, as mCLCA1-expressing lymphatic vessels of the jejunum and dermis were unaffected by 23 h 10.1.1 Ab treatment. These findings demonstrate that 10.1.1 Ab rapidly and specifically induces proliferation and growth of LN lymphatic sinuses and stroma, suggesting a key role of mCLCA1 in coordinating LN remodeling during immune responses. PMID:27224029

  16. Pathway-related molecules of VEGFC/D-VEGFR3/NRP2 axis in tumor lymphangiogenesis and lymphatic metastasis.

    PubMed

    Wang, Jingwen; Huang, Yuhong; Zhang, Jun; Wei, Yuanyi; Mahoud, Salma; Bakheet, Ahmed Musa Hago; Wang, Li; Zhou, Shuting; Tang, Jianwu

    2016-10-01

    Precondition for tumor lymphatic metastasis is that tumor cells induce formation of original and newborn lymphatic vessels and invade surrounding lymphatic vessels in tumor stroma, while some pathway-related molecules play an important role in mechanisms associated with proliferation and migration of lymphatic endothelial cells (LECs) and tumor cells. In lymphangiogenesis and lymphatic metastasis, the pathway-related molecules of VEGFC/D-VEGFR3/NRP2 axis, such as Furin-like enzyme, CNTN1, Prox1, LYVE-1, Podoplanin, SOX18, SDF1 and CXCR4, are direct constitutors as a portion of VEGFC/D-VEGFR3/NRP2 axis, and their biological activities rely on this ligand-receptor system. These axis-related signal molecules could gradually produce waterfall-like cascading effects, mediate differentiation and maturation of LECs, remodel original and neonatal lymphatic vessels, as well as ultimately promote tumor cell chemotaxis, migration, invasion and metastasis to lymphoid tracts. This review summarizes the structure and function features of pathway-related molecules of VEGFC/D-VEGFR3/NRP2 axis, the expression changes of these molecules in different anatomic organs or histopathologic types or development stages of various tumors, the characteristics of transduction, implementation, integration of signal networks, the interactive effects on biological behaviors between tumor cells and lymphatic endothelial cells, and their molecular mechanisms and significances in tumor lymphangiogenesis and lymphatic metastasis.

  17. Altered lymphatic function and architecture in salt-induced hypertension assessed by near-infrared fluorescence imaging

    NASA Astrophysics Data System (ADS)

    Kwon, Sunkuk; Agollah, Germaine D.; Chan, Wenyaw; Sevick-Muraca, Eva M.

    2012-08-01

    The lymphatic system plays an important role in maintaining the fluid homeostasis between the blood vascular and interstitial tissue compartment and there is recent evidence that its transport capabilities may regulate blood pressure in salt-induced hypertension. Yet, there is little known how the lymphatic contractile function and architecture responds to dietary salt-intake. Thus, we longitudinally characterized lymphatic contractile function and vessel remodeling noninvasively using dynamic near-infrared fluorescence imaging in animal models of salt-induced hypertension. The lymphatics of mice and rats were imaged following intradermal injection of indocyanine green to the ear tip or the base of the tail before and during two weeks of either a high salt diet (HSD) or normal chow. Our noninvasive imaging data demonstrated dilated lymphatic vessels in the skin of mice and rats on a HSD as compared to their baseline levels. In addition, our dynamic imaging results showed increased lymphatic contraction frequency in HSD-fed mice and rats. Lymphatic contractile function and vessel remodeling occurs in response to salt-induced hypertension suggesting a possible role for the lymphatics in the regulation of vascular blood pressure.

  18. Pathway-related molecules of VEGFC/D-VEGFR3/NRP2 axis in tumor lymphangiogenesis and lymphatic metastasis.

    PubMed

    Wang, Jingwen; Huang, Yuhong; Zhang, Jun; Wei, Yuanyi; Mahoud, Salma; Bakheet, Ahmed Musa Hago; Wang, Li; Zhou, Shuting; Tang, Jianwu

    2016-10-01

    Precondition for tumor lymphatic metastasis is that tumor cells induce formation of original and newborn lymphatic vessels and invade surrounding lymphatic vessels in tumor stroma, while some pathway-related molecules play an important role in mechanisms associated with proliferation and migration of lymphatic endothelial cells (LECs) and tumor cells. In lymphangiogenesis and lymphatic metastasis, the pathway-related molecules of VEGFC/D-VEGFR3/NRP2 axis, such as Furin-like enzyme, CNTN1, Prox1, LYVE-1, Podoplanin, SOX18, SDF1 and CXCR4, are direct constitutors as a portion of VEGFC/D-VEGFR3/NRP2 axis, and their biological activities rely on this ligand-receptor system. These axis-related signal molecules could gradually produce waterfall-like cascading effects, mediate differentiation and maturation of LECs, remodel original and neonatal lymphatic vessels, as well as ultimately promote tumor cell chemotaxis, migration, invasion and metastasis to lymphoid tracts. This review summarizes the structure and function features of pathway-related molecules of VEGFC/D-VEGFR3/NRP2 axis, the expression changes of these molecules in different anatomic organs or histopathologic types or development stages of various tumors, the characteristics of transduction, implementation, integration of signal networks, the interactive effects on biological behaviors between tumor cells and lymphatic endothelial cells, and their molecular mechanisms and significances in tumor lymphangiogenesis and lymphatic metastasis. PMID:27527412

  19. Lymphatic dysregulation in intestinal inflammation: new insights into inflammatory bowel disease pathomechanisms.

    PubMed

    Becker, F; Yi, P; Al-Kofahi, M; Ganta, V C; Morris, J; Alexander, J S

    2014-03-01

    Alterations in the intestinal lymphatic network are well-established features of human and experimental inflammatory bowel disease (IBD). Such lymphangiogenic expansion might enhance classic intestinal lymphatic transport, eliminating excess accumulations of fluid, inflammatory cells and mediators, and could therefore be interpreted as an 'adaptive' response to acute and chronic inflammatory processes. However, whether these new lymphatic vessels are functional, unregulated or immature (and what factors may promote 'maturation' of these vessels) is currently an area under intense investigation. It is still controversial whether impaired lymphatic function in IBD is a direct consequence of the intestinal inflammation, or a preceding lymphangitis-like event. Current research has uncovered novel regulatory factors as well as new roles for familiar signaling pathways, which appear to be linked to inflammation-induced lymphatic alterations. The current review summarizes mechanisms amplifying lymphatic dysregulation and remodeling in intestinal inflammation at the organ, cell and molecular levels and discusses the influence of lymphangiogenesis and intestinal lymphatic transport function as they relate to IBD pathophysiology.

  20. Vascular Endothelial Growth Factor D Is Dispensable for Development of the Lymphatic System

    PubMed Central

    Baldwin, Megan E.; Halford, Michael M.; Roufail, Sally; Williams, Richard A.; Hibbs, Margaret L.; Grail, Dianne; Kubo, Hajime; Stacker, Steven A.; Achen, Marc G.

    2005-01-01

    Vascular endothelial growth factor receptor 3 (Vegfr-3) is a tyrosine kinase that is expressed on the lymphatic endothelium and that signals for the growth of the lymphatic vessels (lymphangiogenesis). Vegf-d, a secreted glycoprotein, is one of two known activating ligands for Vegfr-3, the other being Vegf-c. Vegf-d stimulates lymphangiogenesis in tissues and tumors; however, its role in embryonic development was previously unknown. Here we report the generation and analysis of mutant mice deficient for Vegf-d. Vegf-d-deficient mice were healthy and fertile, had normal body mass, and displayed no pathologic changes consistent with a defect in lymphatic function. The lungs, sites of strong Vegf-d gene expression during embryogenesis in wild-type mice, were normal in Vegf-d-deficient mice with respect to tissue mass and morphology, except that the abundance of the lymphatics adjacent to bronchioles was slightly reduced. Dye uptake experiments indicated that large lymphatics under the skin were present in normal locations and were functional. Smaller dermal lymphatics were similar in number, location, and function to those in wild-type controls. The lack of a profound lymphatic phenotype in Vegf-d-deficient mice suggests that Vegf-d does not play a major role in lymphatic development or that Vegf-c or another, as-yet-unknown activating Vegfr-3 ligand can compensate for Vegf-d during development. PMID:15743836

  1. Newborn intraabdominal cystic lymphatic malformations.

    PubMed

    Lin, J I; Fisher, J; Caty, M G

    2000-08-01

    Cystic lymphatic malformations are rare causes of abdominal masses in the newborn. Also known as mesenteric, omental, or retroperitoneal cysts, they can present in a variety of ways including, intestinal obstruction, volvulus, nonspecific abdominal pain, intracystic hemorrhage, or as an asymptomatic abdominal mass. Abdominal ultrasound scan provides a definitive diagnosis in most suspected cases. Complete resection is possible in most patients except those with extensive retroperitoneal involvement. Recurrence is unusual when complete resection is accomplished. Because most case series with complete data suggest that these entities are lymphatic malformations, the authors suggest the more specific term, cystic lymphatic malformations, be used to describe these lesions.

  2. Spleen and Lymphatic System

    MedlinePlus

    ... destroy damaged cells. How It Works Carrying Away Waste Lymph fluid drains into tiny vessels called lymph ... crowd out healthy cells and may cause tumors (solid growths) in other parts of the body. Splenomegaly ( ...

  3. Integrin Alpha 9 Blockade Suppresses Lymphatic Valve Formation and Promotes Transplant Survival

    PubMed Central

    Kang, Gyeong Jin; Truong, Tan; Huang, Eric; Su, Valerie; Ge, Shaokui; Chen, Lu

    2016-01-01

    Purpose The lymphatic pathway mediates transplant rejection. We recently reported that lymphatic vessels develop luminal valves in the cornea during lymphangiogenesis, and these valves express integrin alpha 9 (Itga-9) and play a critical role in directing lymph flow. In this study, we used an allogeneic corneal transplantation model to investigate whether Itga-9 blockade could suppress valvulogenesis after transplantation, and how this effect would influence the outcomes of the transplants. Methods Orthotopic corneal transplantation was performed between fully mismatched C57BL/6 (donor) and BALB/c (recipient) mice. The recipients were randomized to receive subconjunctival injections of either Itga-9 blocking antibody or isotype control twice a week for 8 weeks. Corneal grafts were assessed in vivo by ophthalmic slit-lamp biomicroscopy and analyzed using Kaplan-Meier survival curves. Additionally, whole-mount full-thickness corneas were evaluated ex vivo by immunofluorescent microscopy on both lymphatic vessels and valves. Results Anti–Itga-9 treatment suppressed lymphatic valvulogenesis after transplantation. Our treatment did not affect lymphatic vessel formation or their nasal polarized distribution in the cornea. More importantly, Itga-9 blockade led to a significant promotion of graft survival. Conclusions Lymphatic valvulogenesis is critically involved in transplant rejection. Itga-9 targeting may offer a new and effective strategy to interfere with the immune responses and promote graft survival. PMID:27806381

  4. Dual-channel in-situ optical imaging system for quantifying lipid uptake and lymphatic pump function

    NASA Astrophysics Data System (ADS)

    Kassis, Timothy; Kohan, Alison B.; Weiler, Michael J.; Nipper, Matthew E.; Cornelius, Rachel; Tso, Patrick; Brandon Dixon, J.

    2012-08-01

    Nearly all dietary lipids are transported from the intestine to venous circulation through the lymphatic system, yet the mechanisms that regulate this process remain unclear. Elucidating the mechanisms involved in the functional response of lymphatics to changes in lipid load would provide valuable insight into recent implications of lymphatic dysfunction in lipid related diseases. Therefore, we sought to develop an in situ imaging system to quantify and correlate lymphatic function as it relates to lipid transport. The imaging platform provides the capability of dual-channel imaging of both high-speed bright-field video and fluorescence simultaneously. Utilizing post-acquisition image processing algorithms, we can quantify correlations between vessel pump function, lymph flow, and lipid concentration of mesenteric lymphatic vessels in situ. All image analysis is automated with customized LabVIEW virtual instruments; local flow is measured through lymphocyte velocity tracking, vessel contraction through measurements of the vessel wall displacement, and lipid uptake through fluorescence intensity tracking of an orally administered fluorescently labelled fatty acid analogue, BODIPY FL C16. This system will prove to be an invaluable tool for scientists studying intestinal lymphatic function in health and disease, and those investigating strategies for targeting the lymphatics with orally delivered drugs to avoid first pass metabolism.

  5. Dual-channel in-situ optical imaging system for quantifying lipid uptake and lymphatic pump function

    PubMed Central

    Kassis, Timothy; Kohan, Alison B.; Weiler, Michael J.; Nipper, Matthew E.; Cornelius, Rachel; Tso, Patrick

    2012-01-01

    Abstract. Nearly all dietary lipids are transported from the intestine to venous circulation through the lymphatic system, yet the mechanisms that regulate this process remain unclear. Elucidating the mechanisms involved in the functional response of lymphatics to changes in lipid load would provide valuable insight into recent implications of lymphatic dysfunction in lipid related diseases. Therefore, we sought to develop an in situ imaging system to quantify and correlate lymphatic function as it relates to lipid transport. The imaging platform provides the capability of dual-channel imaging of both high-speed bright-field video and fluorescence simultaneously. Utilizing post-acquisition image processing algorithms, we can quantify correlations between vessel pump function, lymph flow, and lipid concentration of mesenteric lymphatic vessels in situ. All image analysis is automated with customized LabVIEW virtual instruments; local flow is measured through lymphocyte velocity tracking, vessel contraction through measurements of the vessel wall displacement, and lipid uptake through fluorescence intensity tracking of an orally administered fluorescently labelled fatty acid analogue, BODIPY FL C16. This system will prove to be an invaluable tool for scientists studying intestinal lymphatic function in health and disease, and those investigating strategies for targeting the lymphatics with orally delivered drugs to avoid first pass metabolism. PMID:23224192

  6. Characterization of primary afferent spinal innervation of mouse uterus.

    PubMed

    Herweijer, Geraldine; Kyloh, Melinda; Beckett, Elizabeth A H; Dodds, Kelsi N; Spencer, Nick J

    2014-01-01

    The primary afferent innervation of the uterus is incompletely understood. The aim of this study was to identify the location and characteristics of primary afferent neurons that innervate the uterine horn of mice and correlate the different morphological types of putative primary afferent nerve endings, immunoreactive to the sensory marker, calcitonin gene related peptide (CGRP). Using retrograde tracing, injection of 5-10 μL of 1,1'-didodecyl-3,3,3,3'-tetramethylindocarbocyanine perchlorate (DiI) into discrete single sites in each uterine horn revealed a biomodal distribution of sensory neurons in dorsal root ganglia (DRG) with peak labeling occurring between T13-L3 and a second smaller peak between L6-S1. The mean cross sectional area of labeled cells was 463 μm(2) ± s.e.m. A significantly greater proportion of labeled neurons consisted of small cell bodies (<300 μm(2)) in the sacral spinal cord (S2) compared with peak labeling at the lumbar (L2) region. In both sections and whole mount preparations, immunohistochemical staining for CGRP revealed substantial innervation of the uterus by CGRP-positive nerve fibers located primarily at the border between the circular and longitudinal muscle layers (N = 4). The nerve endings were classified into three distinct types: "single," "branching," or "complex," that often aligned preferentially in either the circular or longitudinal axis of the smooth muscles. Complex endings were often associated with mesenteric vessels. We have identified that the cell bodies of primary afferent neurons innervating the mouse uterus lie primarily in DRG at L2 and S1 spinal levels. Also, the greatest density of CGRP immunoreactivity lies within the myometrium, with at least three different morphological types of nerve endings identified. These findings will facilitate further investigations into the mechanisms underlying sensory transduction in mouse uterus. PMID:25120416

  7. Cardiovascular effects of afferent renal nerve stimulation.

    PubMed

    Stella, A; Weaver, L; Golin, R; Genovesi, S; Zanchetti, A

    1987-01-01

    Electrical stimulation of afferent renal nerves elicits an increase in arterial pressure and heart rate. The hypertensive response is presumably due to the widespread activation of the sympathetic nervous system leading to peripheral vasoconstriction. Interestingly, the kidney does not appear involved in this reflex excitatory response to afferent renal nerve stimulation since changes in vascular conductances and excretory functions are equal in both the innervated and denervated kidney, and secondary to changes in renal perfusion pressure. In addition, no changes in renin release from either kidneys are observed during afferent renal nerve stimulation. It is likely that the electrical stimulation of afferent renal nerves activates other reflexes exerting an inhibitory influence on efferent renal nerve activity. Indeed, neural renorenal reflexes which tonically inhibit renal functions have clearly been demonstrated. Furthermore, preferential inhibition of efferent renal nerve activity by cardiopulmonary and sinoaortic receptors has recently been shown during activation of other visceral afferents.

  8. Development of Blood and Lymphatic Endothelial Cells in Embryonic and Fetal Human Skin.

    PubMed

    Schuster, Christopher; Mildner, Michael; Botta, Albert; Nemec, Lucas; Rogojanu, Radu; Beer, Lucian; Fiala, Christian; Eppel, Wolfgang; Bauer, Wolfgang; Petzelbauer, Peter; Elbe-Bürger, Adelheid

    2015-09-01

    Blood and lymphatic vessels provide nutrients for the skin and fulfill important homeostatic functions, such as the regulation of immunologic processes. In this study, we investigated the development of blood and lymphatic endothelial cells in prenatal human skin in situ using multicolor immunofluorescence and analyzed angiogenic molecules by protein arrays of lysates and cell culture supernatants. We found that at 8 to 10 weeks of estimated gestational age, CD144(+) vessels predominantly express the venous endothelial cell marker PAL-E, whereas CD144(+)PAL-E(-) vessels compatible with arteries only appear at the end of the first trimester. Lymphatic progenitor cells at 8 weeks of estimated gestational age express CD31, CD144, Prox1, and temporary PAL-E. At that developmental stage not all lymphatic progenitor cells express podoplanin or Lyve-1, which are acquired with advancing gestational age in a stepwise fashion. Already in second-trimester human skin, the phenotype of blood and lymphatic vessels roughly resembles the one in adult skin. The expression pattern of angiogenic molecules in lysates and cell culture supernatants of prenatal skin did not reveal the expected bent to proangiogenic molecules, indicating a complex regulation of angiogenesis during ontogeny. In summary, this study provides enticing new insights into the development and phenotypic characteristics of the vascular system in human prenatal skin.

  9. Near infrared lymphatic imaging demonstrates the dynamics of lymph flow and lymphangiogenesis during the acute vs. chronic phases of arthritis in mice

    PubMed Central

    Zhou, Quan; Wood, Ronald; Schwarz, Edward M.; Wang, Yong-Jun; Xing, Lianping

    2010-01-01

    Objective Development of an in vivo imaging method to assess lymphatic draining function in the K/B×N mouse model of inflammatory arthritis. Methods Indocyanine green (ICG), a near-infrared (NIR) fluorescent dye, was injected intradermally into the footpad of wild-type mice, the limb was illuminated with an 806 nm NIR laser, and the movement of ICG from the injection site to the draining popliteal lymph node (PLN) was recorded with a CCD camera. ICG-NIR images were analyzed to obtain 5 measures of lymphatic function across time. K/B×N arthritic mice and control non-arthritic littermates were imaged at one-month of age when acute joint inflammation commenced, and repeated at 3 months when joint inflammation became chronic. Lymphangiogenesis in PLNs was assessed by immunochemistry. Results ICG and its transport within lymphatic vessels were readily visualized and quantitative measures derived. During the acute phase of arthritis, the lymphatic vessels were dilated with increased ICG signal intensity and lymphatic pulses, and PLNs became fluorescent quickly. During the chronic phase, new lymphatic vessels were present near the foot. However, ICG appearance in lymphatic vessels was delayed. The size and area of PLN lymphatic sinuses progressively increased in the K/B×N mice. Conclusion ICG-NIR lymphatic imaging is a valuable method to assess the lymphatic draining function in mice with inflammatory arthritis. ICG-NIR imaging of K/B×N mice identified two distinct lymphatic phenotypes during the acute and chronic phase of inflammation. This technique can be used to assess new therapies for lymphatic disorders. PMID:20309866

  10. Identification of Vascular Lineage-Specific Genes by Transcriptional Profiling of Isolated Blood Vascular and Lymphatic Endothelial Cells

    PubMed Central

    Hirakawa, Satoshi; Hong, Young-Kwon; Harvey, Natasha; Schacht, Vivien; Matsuda, Kant; Libermann, Towia; Detmar, Michael

    2003-01-01

    In mammals, the lymphatic vascular system develops by budding of lymphatic progenitor endothelial cells from embryonic veins to form a distinct network of draining vessels with important functions in the immune response and in cancer metastasis. However, the lineage-specific molecular characteristics of blood vascular versus lymphatic endothelium have remained poorly defined. We isolated lymphatic endothelial cells (LECs) and blood vascular endothelial cells (BVECs) by immunomagnetic isolation directly from human skin. Cultured LECs but not BVECs expressed the lymphatic markers Prox1 and LYVE-1 and formed LYVE-1-positive vascular tubes after implantation in vivo. Transcriptional profiling studies revealed increased expression of several extracellular matrix and adhesion molecules in BVECs, including versican, collagens, laminin, and N-cadherin, and of the growth factor receptors endoglin and vascular endothelial growth factor receptor-1/Flt-1. Differential immunostains of human skin confirmed the blood vessel-specific expression of these genes. During embryonic development, endoglin expression was gradually down-regulated on lymphatic endothelium whereas vascular endothelial growth factor receptor-1 was absent from lymphatics. We also identified several genes with specific expression in LECs. These results demonstrate that some lineage-specific genes are only expressed during distinct developmental stages and they identify new molecular markers for blood vascular and lymphatic endothelium with important implications for future studies of vascular development and function. PMID:12547715

  11. Lymphatic response to depilation-induced inflammation assessed with label-free optical lymphangiography

    PubMed Central

    Qin, Wan; Baran, Utku; Wang, Ruikang

    2015-01-01

    Background and Objectives Optical microangiography (OMAG) is a noninvasive technique capable of imaging 3D microvasculature. OMAG-based optical lymphangiography has been developed for 3D visualization of lymphatic vessels without the need for exogenous contrast agents. In this study, we utilize the optical lymphangiography to investigate dynamic changes in lymphatic response within skin tissue to depilation-induced inflammation by using mouse ear as a simple tissue model. Materials and Methods A spectral-domain optical coherence tomography (OCT) system is used in this study to acquire volumetric images of mouse ear. The system operates under the ultrahigh-sensitive OMAG scanning protocol with 5 repetitions for each B frame. An improved adaptive-threshold-based method is proposed to segment lymphatic vessels from OCT microstructure images. Depilation is achieved by placing hair removal lotion on mouse ear pinna for 5 minutes. 3 acquisitions are made before depilation, 3-minute and 30-minute post-depilation, respectively. Results Right after the application of depilation lotion on the skin, we observe that the blind-ended sacs of initial lymphatics are mainly visible in a specific area of the normal tissue. At 5 minutes, more collecting lymphatic vessels start to form, evidenced by their valve structure that only exists in collecting lymphatic vessels. The lymphangiogenesis is almost completed within 8 minutes in the inflammatory tissue. Conclusions Our experimental results demonstrate that the OMAG-based optical lymphangiography has great potential to improve the understanding of lymphatic system in response to various physiological conditions, thus would benefit the development of effective therapeutics. PMID:26224650

  12. Dermal lymphatic dilation in a mouse model of alopecia areata.

    PubMed

    Sundberg, John P; Pratt, C Herbert; Silva, Kathleen A; Kennedy, Victoria E; Stearns, Timothy M; Sundberg, Beth A; King, Lloyd E; HogenEsch, Harm

    2016-04-01

    Mouse models of various types of inflammatory skin disease are often accompanied by increased dermal angiogenesis. The C3H/HeJ inbred strain spontaneously develops alopecia areata (AA), a cell mediated autoimmune disorder that can be controllably expanded using full thickness skin grafts to young unaffected mice. This provides a reproducible and progressive model for AA in which the vascularization of the skin can be examined. Mice receiving skin grafts from AA or normal mice were evaluated at 5, 10, 15, and 20 weeks after engraftment. Lymphatics are often overlooked as they are small slit-like structures above the hair follicle that resemble artifact-like separation of collagen bundles with some fixatives. Lymphatics are easily detected using lymphatic vessel endothelial hyaluronan receptor 1 (LYVE1) by immunohistochemistry to label their endothelial cells. Using LYVE1, there were no changes in distribution or numbers of lymphatics although they were more prominent (dilated) in the mice with AA. Lyve1 transcripts were not significantly upregulated except at 10 weeks after skin grafting when clinical signs of AA first become apparent. Other genes involved with vascular growth and dilation or movement of immune cells were dysregulated, mostly upregulated. These findings emphasize aspects of AA not commonly considered and provide potential targets for therapeutic intervention.

  13. Dermal lymphatic dilation in a mouse model of alopecia areata.

    PubMed

    Sundberg, John P; Pratt, C Herbert; Silva, Kathleen A; Kennedy, Victoria E; Stearns, Timothy M; Sundberg, Beth A; King, Lloyd E; HogenEsch, Harm

    2016-04-01

    Mouse models of various types of inflammatory skin disease are often accompanied by increased dermal angiogenesis. The C3H/HeJ inbred strain spontaneously develops alopecia areata (AA), a cell mediated autoimmune disorder that can be controllably expanded using full thickness skin grafts to young unaffected mice. This provides a reproducible and progressive model for AA in which the vascularization of the skin can be examined. Mice receiving skin grafts from AA or normal mice were evaluated at 5, 10, 15, and 20 weeks after engraftment. Lymphatics are often overlooked as they are small slit-like structures above the hair follicle that resemble artifact-like separation of collagen bundles with some fixatives. Lymphatics are easily detected using lymphatic vessel endothelial hyaluronan receptor 1 (LYVE1) by immunohistochemistry to label their endothelial cells. Using LYVE1, there were no changes in distribution or numbers of lymphatics although they were more prominent (dilated) in the mice with AA. Lyve1 transcripts were not significantly upregulated except at 10 weeks after skin grafting when clinical signs of AA first become apparent. Other genes involved with vascular growth and dilation or movement of immune cells were dysregulated, mostly upregulated. These findings emphasize aspects of AA not commonly considered and provide potential targets for therapeutic intervention. PMID:26960166

  14. A tissue engineered model of the intestinal lacteal for evaluating lipid transport by lymphatics

    PubMed Central

    Dixon, J. Brandon; Raghunathan, Sandeep; Swartz, Melody A.

    2010-01-01

    Lacteals are the entry point of all dietary lipids into the circulation, yet little is known about the active regulation of lipid uptake by these lymphatic vessels, and there lacks in vitro models to study the lacteal – enterocyte interface. We describe an in vitro model of the human intestinal microenvironment containing differentiated Caco-2 cells and lymphatic endothelial cells (LECs). We characterize the model for fatty acid, lipoprotein, albumin, and dextran transport, and compare to qualitative uptake of fatty acids into lacteals in vivo. We demonstrate relevant morphological features of both cell types and strongly polarized transport of fatty acid in the intestinal-to-lymphatic direction. We found much higher transport rates of lipid than of dextran or albumin across the lymphatic endothelial monolayer, suggesting most lipid transport is active and intracellular. This was confirmed with confocal imaging of Bodipy, a fluorescent fatty acid, along with transmission electron microscopy. Since our model recapitulates crucial aspects of the in vivo lymphatic-enterocyte interface, it is useful for studying the biology of lipid transport by lymphatics and as a tool for screening drugs and nanoparticles that target intestinal lymphatics. PMID:19396808

  15. Interplay of mechanotransduction, FOXC2, connexins, and calcineurin signaling in lymphatic valve formation.

    PubMed

    Sabine, Amélie; Petrova, Tatiana V

    2014-01-01

    The directional flow of lymph is maintained by hundreds of intraluminal lymphatic valves. Lymphatic valves are crucial to prevent lymphedema, accumulation of fluid in the tissues, and to ensure immune surveillance; yet, the mechanisms of valve formation are only beginning to be elucidated. In this chapter, we will discuss the main steps of lymphatic valve morphogenesis, the important role of mechanotransduction in this process, and the genetic program regulated by the transcription factor Foxc2, which is indispensable for all steps of valve development. Failure to form mature collecting lymphatic vessels and valves causes the majority of postsurgical lymphedema, e.g., in breast cancer patients. Therefore, this knowledge will be useful for diagnostics and development of better treatments of secondary lymphedema.

  16. Minimally invasive method for determining the effective lymphatic pumping pressure in rats using near-infrared imaging.

    PubMed

    Nelson, Tyler S; Akin, Ryan E; Weiler, Michael J; Kassis, Timothy; Kornuta, Jeffrey A; Dixon, J Brandon

    2014-03-01

    The ability to quantify collecting vessel function in a minimally invasive fashion is crucial to the study of lymphatic physiology and the role of lymphatic pump function in disease progression. Therefore, we developed a highly sensitive, minimally invasive research platform for quantifying the pumping capacity of collecting lymphatic vessels in the rodent tail and forelimb. To achieve this, we have integrated a near-infrared lymphatic imaging system with a feedback-controlled pressure cuff to modulate lymph flow. After occluding lymphatic flow by inflating a pressure cuff on the limb or tail, we gradually deflate the cuff while imaging flow restoration proximal to the cuff. Using prescribed pressure applications and automated image processing of fluorescence intensity levels in the vessels, we were able to noninvasively quantify the effective pumping pressure (P(eff), pressure at which flow is restored after occlusion) and vessel emptying rate (rate of fluorescence clearance during flow occlusion) of lymphatics in the rat. To demonstrate the sensitivity of this system to changes in lymphatic function, a nitric oxide (NO) donor cream, glyceryl trinitrate ointment (GTNO), was applied to the tails. GTNO decreased P(eff) of the vessels by nearly 50% and the average emptying rate by more than 60%. We also demonstrate the suitability of this approach for acquiring measurements on the rat forelimb. Thus, this novel research platform provides the first minimally invasive measurements of P(eff) and emptying rate in rodents. This experimental platform holds strong potential for future in vivo studies that seek to evaluate changes in lymphatic health and disease.

  17. [Some recent, or claiming to be recent, data on the superficial lymphatic circulation of the limbs].

    PubMed

    Hidden, G

    1990-01-01

    Superficial collecting lymphatics of the limbs are present in much greater number than deep collecting vessels. There is practically no connexion between both networks. Although lymphatics are abundant distally, they tend to fuse toward the root of the limb. At certain "critical" points along their course, local aggression of the vessels may cause lymphedema. In the lower extremity, at the knee and thigh levels, the "critical" area takes the form of a narrow strip of adipose tissue along the path of the great saphenous vein. In the groin, danger is localized at the inferior superficial inguinal nodes, where the superficial collecting lymph vessels merge. In the upper limb, superficial lymphatics converge towards the base of the axilla, where they form three or four trunks that perforate the clavipectoral fascia, each penetrating through its own orifice. Draining lymphatics may approach the axillary space independently. Unfortunately, the inferior axillary nodes wherein they converge also drain the breast, as can be demonstrated by injecting different coloring materials concurrently in both areas. Excision of nodes draining the mammary gland unavoidably jeopardize superficial lymphatic drainage of the upper extremity.

  18. Colonic insult impairs lymph flow, increases cellular content of the lymph, alters local lymphatic micro-environment and leads to sustained inflammation in the rat ileum

    PubMed Central

    Cromer, Walter; Wang, Wei; Zawieja, Scott D.; von der Weid, Pierre-Yves; Newell Rogers, M. Karen; Zawieja, David C.

    2015-01-01

    Background Lymphatic dysfunction has been linked to inflammation since the 1930’s. Lymphatic function in the gut and mesentery is grossly underexplored in models of IBD despite the use of lymphatic occlusion in early models of IBD. Activation of the innate and adaptive immune system is a hallmark of TNBS-induced inflammation and is linked to disruption of the intrinsic lymph pump. Recent identification of crosstalk between lymphatic vessel resident immune cells and regulation of lymphatic vessel contractility underscore the importance of the timing of lymphatic dysfunction during tissue inflammation in response to TNBS. Methods To evaluate lymphatic function in TNBS induced inflammation, lymph was collected and flow measured from mesenteric lymphatics. Cellularity and cytokine profile of the lymph was also measured. Histopathology was performed to determine severity of injury and immunofluorescent staining of the mesentery was done to evaluate changes in the population of immune cells that reside near and on gastro-intestinal collecting lymphatics. Results Lymph transport fell 24hrs after TNBS administration and began recovering at 72hrs. Significant reduction of lymph flow preceded significant increase in histopathological score and occurred simultaneously with increased MPO activity. These changes were preceded by increased MHCII+ cells surrounding mesenteric lymphatics leading to an altered lymphatic environment that would favor dysfunction. Conclusions Alterations in environmental factors that effect lymphatic function occur before the development of gross GI inflammation. Reduced lymphatic function in TNBS-mediated inflammation is likely an early factor in the development of injury and that recovery of function is associated with resolution of inflammation. PMID:25939039

  19. Activation of intestinal spinal afferent endings by changes in intra-mesenteric arterial pressure

    PubMed Central

    Humenick, A; Chen, B N; Wiklendt, L; Spencer, N J; Zagorodnyuk, V P; Dinning, P G; Costa, M; Brookes, S J H

    2015-01-01

    Spinal sensory neurons innervate many large blood vessels throughout the body. Their activation causes the hallmarks of neurogenic inflammation: vasodilatation through the release of the neuropeptide calcitonin gene-related peptide and plasma extravasation via tachykinins. The same vasodilator afferent neurons show mechanical sensitivity, responding to crushing, compression or axial stretch of blood vessels – responses which activate pain pathways and which can be modified by cell damage and inflammation. In the present study, we tested whether spinal afferent axons ending on branching mesenteric arteries (‘vascular afferents’) are sensitive to increased intravascular pressure. From a holding pressure of 5 mmHg, distension to 20, 40, 60 or 80 mmHg caused graded, slowly adapting increases in firing of vascular afferents. Many of the same afferent units showed responses to axial stretch, which summed with responses evoked by raised pressure. Many vascular afferents were also sensitive to raised temperature, capsaicin and/or local compression with von Frey hairs. However, responses to raised pressure in single, isolated vessels were negligible, suggesting that the adequate stimulus is distortion of the arterial arcade rather than distension per se. Increasing arterial pressure often triggered peristaltic contractions in the neighbouring segment of intestine, an effect that was mimicked by acute exposure to capsaicin (1 μm) and which was reduced after desensitisation to capsaicin. These results indicate that sensory fibres with perivascular endings are sensitive to pressure-induced distortion of branched arteries, in addition to compression and axial stretch, and that they contribute functional inputs to enteric motor circuits. PMID:26010893

  20. Platelet interaction with lymphatics aggravates intestinal inflammation by suppressing lymphangiogenesis.

    PubMed

    Sato, Hirokazu; Higashiyama, Masaaki; Hozumi, Hideaki; Sato, Shingo; Furuhashi, Hirotaka; Takajo, Takeshi; Maruta, Koji; Yasutake, Yuichi; Narimatsu, Kazuyuki; Yoshikawa, Kenichi; Kurihara, Chie; Okada, Yoshikiyo; Watanabe, Chikako; Komoto, Shunsuke; Tomita, Kengo; Nagao, Shigeaki; Miura, Soichiro; Hokari, Ryota

    2016-08-01

    Lymphatic failure is a histopathological feature of inflammatory bowel disease (IBD). Recent studies show that interaction between platelets and podoplanin on lymphatic endothelial cells (LECs) suppresses lymphangiogenesis. We aimed to investigate the role of platelets in the inflammatory process of colitis, which is likely to be through modulation of lymphangiogenesis. Lymphangiogenesis in colonic mucosal specimens from patients with IBD was investigated by studying mRNA expression of lymphangiogenic factors and histologically by examining lymphatic vessel (LV) densities. Involvement of lymphangiogenesis in intestinal inflammation was studied by administering VEGF-receptor 3 (VEGF-R3) inhibitors to the mouse model of colitis using dextran sulfate sodium and evaluating platelet migration to LVs. The inhibitory effect of platelets on lymphangiogenesis was investigated in vivo by administering antiplatelet antibody to the colitis mouse model and in vitro by coculturing platelets with lymphatic endothelial cells. Although mRNA expressions of lymphangiogenic factors such as VEGF-R3 and podoplanin were significantly increased in the inflamed mucosa of patients with IBD compared with those with quiescent mucosa, there was no difference in LV density between them. In the colitis model, VEGF-R3 inhibition resulted in aggravated colitis, decreased lymphatic density, and increased platelet migration to LVs. Administration of an antiplatelet antibody increased LV densities and significantly ameliorated colitis. Coculture with platelets inhibited proliferation of LECs in vitro. Our data suggest that despite elevated lymphangiogenic factors during colonic inflammation, platelet migration to LVs resulted in suppressed lymphangiogenesis, leading to aggravation of colitis by blocking the clearance of inflammatory cells. Modulating the interaction between platelets and LVs could be a new therapeutic means for treating IBD.

  1. Altered lymphatics in an ovine model of congenital heart disease with increased pulmonary blood flow.

    PubMed

    Datar, Sanjeev A; Johnson, Eric G; Oishi, Peter E; Johengen, Michael; Tang, Eric; Aramburo, Angela; Barton, Jubilee; Kuo, Hsuan-Chang; Bennett, Stephen; Xoinis, Konstantine; Reel, Bhupinder; Kalkan, Gokhan; Sajti, Eniko; Osorio, Oscar; Raff, Gary W; Matthay, Michael A; Fineman, Jeffrey R

    2012-03-15

    Abnormalities of the lymphatic circulation are well recognized in patients with congenital heart defects. However, it is not known how the associated abnormal blood flow patterns, such as increased pulmonary blood flow (PBF), might affect pulmonary lymphatic function and structure. Using well-established ovine models of acute and chronic increases in PBF, we cannulated the efferent lymphatic duct of the caudal mediastinal node and collected and analyzed lymph effluent from the lungs of lambs with acutely increased PBF (n = 6), chronically increased PBF (n = 6), and age-matched normal lambs (n = 8). When normalized to PBF, we found that lymph flow was unchanged following acute increases in PBF but decreased following chronic increases in PBF. The lymph:plasma protein ratio decreased with both acute and chronic increases in PBF. Lymph bioavailable nitric oxide increased following acute increases in PBF but decreased following chronic increases in PBF. In addition, we found perturbations in the transit kinetics of contrast material through the pleural lymphatics of lambs with chronic increases in PBF. Finally, there were structural changes in the pulmonary lymphatic system in lambs with chronic increases in PBF: lymphatics from these lambs were larger and more dilated, and there were alterations in the expression of vascular endothelial growth factor-C, lymphatic vessel endothelial hyaluronan receptor-1, and Angiopoietin-2, proteins known to be important for lymphatic growth, development, and remodeling. Taken together these data suggest that chronic increases in PBF lead to both functional and structural aberrations of lung lymphatics. These findings have important therapeutic implications that warrant further study.

  2. Conserved signaling through vascular endothelial growth (VEGF) receptor family members in murine lymphatic endothelial cells.

    PubMed

    Coso, Sanja; Zeng, Yiping; Sooraj, Dhanya; Williams, Elizabeth D

    2011-10-15

    Lymphatic vessels guide interstitial fluid, modulate immune responses by regulating leukocyte and antigen trafficking to lymph nodes, and in a cancer setting enable tumor cells to track to regional lymph nodes. The aim of the study was to determine whether primary murine lymphatic endothelial cells (mLECs) show conserved vascular endothelial growth factor (VEGF) signaling pathways with human LECs (hLECs). LECs were successfully isolated from murine dermis and prostate. Similar to hLECs, vascular endothelial growth factor (VEGF) family ligands activated MAPK and pAkt intracellular signaling pathways in mLECs. We describe a robust protocol for isolation of mLECs which, by harnessing the power of transgenic and knockout mouse models, will be a useful tool to study how LEC phenotype contributes to alterations in lymphatic vessel formation and function.

  3. Possible involvement of tumor-producing VEGF-A in the recruitment of lymphatic endothelial progenitor cells from bone marrow.

    PubMed

    Tawada, Masahiro; Hayashi, Shin-Ichiro; Ikegame, Yuka; Nakashima, Shigeru; Yoshida, Kazuhiro

    2014-12-01

    Lymphatic metastasis of human malignant adenocarcinomas is a critical determinant of prognosis. Lymphangiogenesis, the growth of lymphatic vessels, is closely involved in lymphatic metastasis. However, the mechanisms of tumor lymphangiogenesis are not clearly understood. In a previous study, we showed that human gastric cancer MKN45 cells organize neighboring lymphatic vessels via recruitment of bone marrow-derived lymphatic endothelial progenitor cells in a nude mouse xenograft model. The present results also indicated that human colorectal cancer LS174T and breast cancer SK-BR-3 cells promoted lymphangiogenesis as well as the recruitment of lymphatic endothelial progenitor cells from bone marrow. Among growth factors, which are reported to be involved in lymphangiogenesis, only vascular endothelial growth factor (VEGF)-A was extensively secreted by these three types of adenocarcinoma cells in culture. The well-characterized lymphangiogenic factors VEGF-C and VEGF-D in the culture medium of these three types of adenocarcinoma cells were below the detectable levels in ELISA assay. Secretion of epidermal growth factor (EGF) and hepatocyte growth factor (HGF) was not detected. In in vitro culture assay, VEGF-A directly induced the differentiation of bone marrow mononuclear cells into LYVE-1-positive lymphatic endothelial lineage cells. These data collectively suggest the possibility that VEGF-A-rich human adenocarcinomas induce tumor lymphangiogenesis via recruitment of lymphangiogenic endothelial progenitor cells from bone marrow. PMID:25242215

  4. Functional imaging in tumor-associated lymphatics

    NASA Astrophysics Data System (ADS)

    Kwon, Sunkuk; Sevick-Muraca, Eva M.

    2011-03-01

    The lymphatic system plays an important role in cancer cell dissemination; however whether lymphatic drainage pathways and function change during tumor progression and metastasis remains to be elucidated. In this report, we employed a non-invasive, dynamic near-infrared (NIR) fluorescence imaging technique for functional lymphatic imaging. Indocyanine green (ICG) was intradermally injected into tumor-free mice and mice bearing C6/LacZ rat glioma tumors in the tail or hindlimb. Our imaging data showed abnormal lymphatic drainage pathways and reduction/loss of lymphatic contractile function in mice with lymph node (LN) metastasis, indicating that cancer metastasis to the draining LNs is accompanied by transient changes of the lymphatic architectural network and its function. Therefore, functional lymphatic imaging may provide a role in the clinical staging of cancer.

  5. Piezo2 expression in corneal afferent neurons.

    PubMed

    Bron, Romke; Wood, Rhiannon J; Brock, James A; Ivanusic, Jason J

    2014-09-01

    Recently, a novel class of mechanically sensitive channels has been identified and have been called Piezo channels. In this study, we explored Piezo channel expression in sensory neurons supplying the guinea pig corneal epithelium, which have well-defined modalities in this species. We hypothesized that a proportion of corneal afferent neurons express Piezo2, and that these neurons are neurochemically distinct from corneal polymodal nociceptors or cold-sensing neurons. We used a combination of retrograde tracing to identify corneal afferent neurons and double label in situ hybridization and/or immunohistochemistry to determine their molecular and/or neurochemical profile. We found that Piezo2 expression occurs in ∼26% of trigeminal ganglion neurons and 30% of corneal afferent neurons. Piezo2 corneal afferent neurons are almost exclusively non-calcitonin gene-related peptide (CGRP)-immunoreactive (-IR), medium- to large-sized neurons that are NF200-IR, suggesting they are not corneal polymodal nociceptors. There was no coexpression of Piezo2 and transient receptor potential cation channel subfamily M member 8 (TRPM8) transcripts in any corneal afferent neurons, further suggesting that Piezo2 is not expressed in corneal cold-sensing neurons. We also noted that TRPM8-IR or CGRP-IR corneal afferent neurons are almost entirely small and lack NF200-IR. Piezo2 expression occurs in a neurochemically distinct subpopulation of corneal afferent neurons that are not polymodal nociceptors or cold-sensing neurons, and is likely confined to a subpopulation of pure mechano-nociceptors in the cornea. This provides the first evidence in an in vivo system that Piezo2 is a strong candidate for a channel that transduces noxious mechanical stimuli.

  6. A Lymphatic dwelling filarioid nematode, Rumenfilaria andersoni (Filarioidea; Splendidofilariinae), is an emerging parasite in Finnish cervids

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Background-Recent studies revealed expansion of filarioid nematodes into the northern Finland. In addition to Setaria tundra, unidentified and very abundant filarioids, representing Rumenfilaria andersoni, were found inhabiting the lymphatic vessels of reindeer. Our study explores the biology and d...

  7. Afferent Connectivity of the Zebrafish Habenulae

    PubMed Central

    Turner, Katherine J.; Hawkins, Thomas A.; Yáñez, Julián; Anadón, Ramón; Wilson, Stephen W.; Folgueira, Mónica

    2016-01-01

    The habenulae are bilateral nuclei located in the dorsal diencephalon that are conserved across vertebrates. Here we describe the main afferents to the habenulae in larval and adult zebrafish. We observe afferents from the subpallium, nucleus rostrolateralis, posterior tuberculum, posterior hypothalamic lobe, median raphe; we also see asymmetric afferents from olfactory bulb to the right habenula, and from the parapineal to the left habenula. In addition, we find afferents from a ventrolateral telencephalic nucleus that neurochemical and hodological data identify as the ventral entopeduncular nucleus (vENT), confirming and extending observations of Amo et al. (2014). Fate map and marker studies suggest that vENT originates from the diencephalic prethalamic eminence and extends into the lateral telencephalon from 48 to 120 hour post-fertilization (hpf). No afferents to the habenula were observed from the dorsal entopeduncular nucleus (dENT). Consequently, we confirm that the vENT (and not the dENT) should be considered as the entopeduncular nucleus “proper” in zebrafish. Furthermore, comparison with data in other vertebrates suggests that the vENT is a conserved basal ganglia nucleus, being homologous to the entopeduncular nucleus of mammals (internal segment of the globus pallidus of primates) by both embryonic origin and projections, as previously suggested by Amo et al. (2014). PMID:27199671

  8. Vestibular afferent responses to microrotational stimuli

    NASA Technical Reports Server (NTRS)

    Myers, Steven F.; Lewis, Edwin R.

    1991-01-01

    Intracellular microelectrode recording/labeling techniques were used to investigate vestibular afferent responses in the bullfrog, to very small amplitude (less than 5 deg p-p) sinusoidal rotations in the vertical plane over the frequency range of 0.063-4 Hz. Robust responses to peak accelerations as low as 0.031 deg/sec per sec were obtained from units subsequently traced to either the central portion of the anterior canal crista or the striolar region of the utricle. All of these microrotationally sensitive afferent neurons had irregular resting discharge rates, and the majority had transfer ratios (relative to rotational velocity) of 1-40 spikes/sec per deg/sec. Individual utricular afferent velocity transfer ratios were nearly constant over the frequency range of 0.125-4 Hz. Canal units displayed decreasing response transfer ratios as stimulus frequencies increased. These findings indicate that, although utricular striolar and central crista afferent velocity transfer ratios to microrotations were very similar, utricular striolar afferent neurons were more faithful sensors of very small amplitude rotational velocity in the vertical plane.

  9. Integration of CD45-positive leukocytes into newly forming lymphatics of adult mice.

    PubMed

    Buttler, K; Lohrberg, M; Gross, G; Weich, H A; Wilting, J

    2016-06-01

    The embryonic origin of lymphatic endothelial cells (LECs) has been a matter of controversy since more than a century. However, recent studies in mice have supported the concept that embryonic lymphangiogenesis is a complex process consisting of growth of lymphatics from specific venous segments as well as the integration of lymphangioblasts into the lymphatic networks. Similarly, the mechanisms of adult lymphangiogenesis are poorly understood and have rarely been studied. We have recently shown that endothelial progenitor cells isolated from the lung of adult mice have the capacity to form both blood vessels and lymphatics when grafted with Matrigel plugs into the skin of syngeneic mice. Here, we followed up on these experiments and studied the behavior of host leukocytes during lymphangiogenesis in the Matrigel plugs. We observed a striking co-localization of CD45(+) leukocytes with the developing lymphatics. Numerous CD45(+) cells expressed the LEC marker podoplanin and were obviously integrated into the lining of lymphatic capillaries. This indicates that, similar to inflammation-induced lymphangiogenesis in man, circulating CD45(+) cells of adult mice are capable of initiating lymphangiogenesis and of adopting a lymphvasculogenic cellular differentiation program. The data are discussed in the context of embryonic and inflammation-induced lymphangiogenesis. PMID:26748643

  10. Detection thresholds of macaque otolith afferents.

    PubMed

    Yu, Xiong-Jie; Dickman, J David; Angelaki, Dora E

    2012-06-13

    The vestibular system is our sixth sense and is important for spatial perception functions, yet the sensory detection and discrimination properties of vestibular neurons remain relatively unexplored. Here we have used signal detection theory to measure detection thresholds of otolith afferents using 1 Hz linear accelerations delivered along three cardinal axes. Direction detection thresholds were measured by comparing mean firing rates centered on response peak and trough (full-cycle thresholds) or by comparing peak/trough firing rates with spontaneous activity (half-cycle thresholds). Thresholds were similar for utricular and saccular afferents, as well as for lateral, fore/aft, and vertical motion directions. When computed along the preferred direction, full-cycle direction detection thresholds were 7.54 and 3.01 cm/s(2) for regular and irregular firing otolith afferents, respectively. Half-cycle thresholds were approximately double, with excitatory thresholds being half as large as inhibitory thresholds. The variability in threshold among afferents was directly related to neuronal gain and did not depend on spike count variance. The exact threshold values depended on both the time window used for spike count analysis and the filtering method used to calculate mean firing rate, although differences between regular and irregular afferent thresholds were independent of analysis parameters. The fact that minimum thresholds measured in macaque otolith afferents are of the same order of magnitude as human behavioral thresholds suggests that the vestibular periphery might determine the limit on our ability to detect or discriminate small differences in head movement, with little noise added during downstream processing.

  11. Optimization of monoclonal antibody delivery via the lymphatics: the dose dependence

    SciTech Connect

    Steller, M.A.; Parker, R.J.; Covell, D.G.; Holton, O.D. 3d.; Keenan, A.M.; Sieber, S.M.; Weinstein, J.N.

    1986-04-01

    After interstitial injection in mice, antibody molecules enter local lymphatic vessels, flow with the lymph to regional lymph nodes, and bind to target antigens there. Compared with i.v. administration, delivery via the lymphatics provides a more efficient means for localizing antibody in lymph nodes. An IgG2a (36-7-5) directed against the murine class I major histocompatibility antigen H-2Kk has proved useful for studying the pharmacology of lymphatic delivery. At very low doses, most of the antibody remains at the injection site in Kk-positive animals. As the dose is progressively increased, most effective labeling occurs first in nodes proximal to the injection site and then in the next group of nodes along the lymphatic chain. At higher doses, antibody overflows the lymphatic system and enters the blood-stream via the thoracic duct and other lymphatic-venous connections. Once in the blood, antibody is rapidly cleared, apparently by binding to Kk-bearing cells. These findings indicate that the single-pass distribution of monoclonal antibodies in the lymphatics can be strongly dose dependent, a principle which may be of clinical significance in the improvement of immunolymphoscintigraphic imaging, especially with antibodies directed against normal and malignant lymphoid cells. Monoclonal antibodies directed against normal cell types in the lymph node may be useful for assessing the integrity of lymphatic chains by immunolymphoscintigraphy or, more speculatively, for altering the status of regional immune function. The results presented here indicate that a low or intermediate antibody dose may optimize the signal:noise ratio for imaging. In Kk-negative animals, the percentage of dose taken up in the major organs was essentially independent of the dose administered; there was no evidence for saturable sites of nonspecific binding.

  12. Lymphatic endothelial cells are a replicative niche for Mycobacterium tuberculosis

    PubMed Central

    Lerner, Thomas R.; de Souza Carvalho-Wodarz, Cristiane; Repnik, Urska; Russell, Matthew R.G.; Borel, Sophie; Diedrich, Collin R.; Rohde, Manfred; Wainwright, Helen; Collinson, Lucy M.; Wilkinson, Robert J.; Griffiths, Gareth; Gutierrez, Maximiliano G.

    2016-01-01

    In extrapulmonary tuberculosis, the most common site of infection is within the lymphatic system, and there is growing recognition that lymphatic endothelial cells (LECs) are involved in immune function. Here, we identified LECs, which line the lymphatic vessels, as a niche for Mycobacterium tuberculosis in the lymph nodes of patients with tuberculosis. In cultured primary human LECs (hLECs), we determined that M. tuberculosis replicates both in the cytosol and within autophagosomes, but the bacteria failed to replicate when the virulence locus RD1 was deleted. Activation by IFN-γ induced a cell-autonomous response in hLECs via autophagy and NO production that restricted M. tuberculosis growth. Thus, depending on the activation status of LECs, autophagy can both promote and restrict replication. Together, these findings reveal a previously unrecognized role for hLECs and autophagy in tuberculosis pathogenesis and suggest that hLECs are a potential niche for M. tuberculosis that allows establishment of persistent infection in lymph nodes. PMID:26901813

  13. Lymphatic endothelial cells are a replicative niche for Mycobacterium tuberculosis.

    PubMed

    Lerner, Thomas R; de Souza Carvalho-Wodarz, Cristiane; Repnik, Urska; Russell, Matthew R G; Borel, Sophie; Diedrich, Collin R; Rohde, Manfred; Wainwright, Helen; Collinson, Lucy M; Wilkinson, Robert J; Griffiths, Gareth; Gutierrez, Maximiliano G

    2016-03-01

    In extrapulmonary tuberculosis, the most common site of infection is within the lymphatic system, and there is growing recognition that lymphatic endothelial cells (LECs) are involved in immune function. Here, we identified LECs, which line the lymphatic vessels, as a niche for Mycobacterium tuberculosis in the lymph nodes of patients with tuberculosis. In cultured primary human LECs (hLECs), we determined that M. tuberculosis replicates both in the cytosol and within autophagosomes, but the bacteria failed to replicate when the virulence locus RD1 was deleted. Activation by IFN-γ induced a cell-autonomous response in hLECs via autophagy and NO production that restricted M. tuberculosis growth. Thus, depending on the activation status of LECs, autophagy can both promote and restrict replication. Together, these findings reveal a previously unrecognized role for hLECs and autophagy in tuberculosis pathogenesis and suggest that hLECs are a potential niche for M. tuberculosis that allows establishment of persistent infection in lymph nodes.

  14. Multivalent Vaccine for Lymphatic Filariasis

    PubMed Central

    Samykutty, Abhilash; Dakshinamoorthy, Gajalakshmi; Kalyanasundaram, Ramaswamy

    2011-01-01

    Lymphatic filariasis is a mosquito borne parasitic infection that cause severe economic burden in several parts of the world. Currently there is no vaccine available to prevent this infection in human. Multidrug therapy is effective, however, requires annual treatment and there is significant concern of drug resistance. In this manuscript we describe development of a multivalent DNA based vaccine comprising BmALT-2 and BmHSP antigens of lymphatic filariasis. Challenge experiments using third stage infective larvae of Brugia malayi in a mouse model suggested that nearly 90% protection can be achieved using the multivalent formulation in a DNA prime protein boost approach. The vaccination regimen induced significant IgG antibody responses and ELISPOT analysis for secreted cytokines from the spleen cells of vaccinated animals showed that these cells produce significant amount of IL-4. Results from this study thus show that a multivalent vaccine formulation of BmALT-2 and BmHSP is an excellent vaccine for lymphatic filariasis and significant protection can be achieved against a challenge infection with B. malayi in a mouse model. PMID:21709765

  15. Multivalent Vaccine for Lymphatic Filariasis.

    PubMed

    Samykutty, Abhilash; Dakshinamoorthy, Gajalakshmi; Kalyanasundaram, Ramaswamy

    2010-01-01

    Lymphatic filariasis is a mosquito borne parasitic infection that cause severe economic burden in several parts of the world. Currently there is no vaccine available to prevent this infection in human. Multidrug therapy is effective, however, requires annual treatment and there is significant concern of drug resistance. In this manuscript we describe development of a multivalent DNA based vaccine comprising BmALT-2 and BmHSP antigens of lymphatic filariasis. Challenge experiments using third stage infective larvae of Brugia malayi in a mouse model suggested that nearly 90% protection can be achieved using the multivalent formulation in a DNA prime protein boost approach. The vaccination regimen induced significant IgG antibody responses and ELISPOT analysis for secreted cytokines from the spleen cells of vaccinated animals showed that these cells produce significant amount of IL-4. Results from this study thus show that a multivalent vaccine formulation of BmALT-2 and BmHSP is an excellent vaccine for lymphatic filariasis and significant protection can be achieved against a challenge infection with B. malayi in a mouse model.

  16. Methods for effective fluorophore injection and imaging of lymphatics in small animals

    NASA Astrophysics Data System (ADS)

    DSouza, Alisha V.; Marra, Kayla A.; Gunn, Jason R.; Samkoe, Kimberley S.; Tichauer, Kenneth M.; Pogue, Brian W.

    2016-03-01

    Morbidity and complexity involved in lymph node staging via surgical resection and biopsy calls for staging techniques that are less invasive. While visible blue dyes are commonly used in locating sentinel lymph nodes, since they follow tumor-draining lymphatic vessels, they do not provide a metric to evaluate presence of cancer. An area of active research is to use fluorescent dyes to assess tumor burden of sentinel and secondary lymph nodes. The goal of this work was to successfully perform fluorescence imaging of IRDye®680RD in the lymphatics, in a repeatable manner.

  17. The discovery of the synovial lymphatic stomata and lymphatic reabsorption in knee effusion.

    PubMed

    Ping, Zepeng; Jiang, Tingting; Wang, Chong; Chen, Zhongyi; Chen, Zhongliang; Wang, Jiaxiong; Wang, Li; Wang, Beibei; Xu, Dandan; Liu, Changming; Li, Zhongjie; Li, Ji-Cheng

    2015-06-01

    To illustrate the mechanism of lymphatic reabsorption in knee joint effusion. The current investigation employed transmission electron microscopy (TEM) and scanning electron microscopy (SEM) techniques to reveal the ultrastructure of the knee synovial membrane in New Zealand rabbits and human. Ultrastructural changes of the synovial lymphatic stomata were observed by using trypan blue absorption and sodium hydroxide (NaOH) digestion methods, and the animal models of synovitis. New Zealand rabbits and human synovial membranes were composed of two types of synovial cells: type A and type B. No lymphatic stomata were found among type A synovial cells, whereas lymphatic stomata with the diameters ranging 0.74-3.26 µm were found in type B synovial cells, and some stomata were closed. After the NaOH digestion, a number of sieve pores, similar to lymphatic stomata in size and shape, were observed in the dense fibrous connective tissue underneath the type B synovial cells. After injecting trypan blue into the rabbit knee joint cavity, absorption of trypan blue through the lymphatic stomata was observed, suggesting the absorption function of the synovial lymphatic stomata. In the rabbit knee joint synovitis models, the synovial lymphatic stomata diameter enlarged. Some macrophages migrated from the lymphatic stomata, indicating that the synovial lymphatic stomata were involved in the joint effusion absorption and inflammatory response. Our study is the first to report the existence of synovial lymphatic stomata in the New Zealand rabbits and human knee joints. Lymphatic stomata may have an important role in the reabsorption of joint effusion.

  18. Acute neonatal presentation of a lymphatic malformation

    PubMed Central

    Tang, Chee Yan; Wijnen, M; Sambeeck van, S J; Halbertsma, F J J

    2013-01-01

    Oropharyngeal lymphatic malformations usually present with a mass either at birth or in the first 2 years of life. Rarely, lymphatic malformations present with extremely progressive respiratory problems shortly after birth, and usually occur in cases which have remained undetected in the absence of antenatal ultrasound. We report the case of a newborn that required tracheostomy and gastrostomy due to a rapidly expansive lymphatic malformation. MRI showed multilocular microcystic lymphatic malformation. Intralesional bleomycin injections proved to be successful in this patient. A short review of epidemiology, clinical manifestation and treatment is given. PMID:23907961

  19. TGF-β1-induced EMT promotes targeted migration of breast cancer cells through the lymphatic system by the activation of CCR7/CCL21-mediated chemotaxis.

    PubMed

    Pang, M-F; Georgoudaki, A-M; Lambut, L; Johansson, J; Tabor, V; Hagikura, K; Jin, Y; Jansson, M; Alexander, J S; Nelson, C M; Jakobsson, L; Betsholtz, C; Sund, M; Karlsson, M C I; Fuxe, J

    2016-02-11

    Tumor cells frequently disseminate through the lymphatic system during metastatic spread of breast cancer and many other types of cancer. Yet it is not clear how tumor cells make their way into the lymphatic system and how they choose between lymphatic and blood vessels for migration. Here we report that mammary tumor cells undergoing epithelial-mesenchymal transition (EMT) in response to transforming growth factor-β (TGF-β1) become activated for targeted migration through the lymphatic system, similar to dendritic cells (DCs) during inflammation. EMT cells preferentially migrated toward lymphatic vessels compared with blood vessels, both in vivo and in 3D cultures. A mechanism of this targeted migration was traced to the capacity of TGF-β1 to promote CCR7/CCL21-mediated crosstalk between tumor cells and lymphatic endothelial cells. On one hand, TGF-β1 promoted CCR7 expression in EMT cells through p38 MAP kinase-mediated activation of the JunB transcription factor. Blockade of CCR7, or treatment with a p38 MAP kinase inhibitor, reduced lymphatic dissemination of EMT cells in syngeneic mice. On the other hand, TGF-β1 promoted CCL21 expression in lymphatic endothelial cells. CCL21 acted in a paracrine fashion to mediate chemotactic migration of EMT cells toward lymphatic endothelial cells. The results identify TGF-β1-induced EMT as a mechanism, which activates tumor cells for targeted, DC-like migration through the lymphatic system. Furthermore, it suggests that p38 MAP kinase inhibition may be a useful strategy to inhibit EMT and lymphogenic spread of tumor cells.

  20. Patterns of saccular afferent innervation in sciaenids.

    PubMed

    Selckmann, G M; Ramcharitar, J

    2013-09-01

    In this study, saccular afferent arborization patterns in Atlantic croaker Micropogonias undulatus, red drum Sciaenops ocellatus and spot Leiostomus xanthurus were characterized. Leiostomus xanthurus showed the simplest configuration while M. undulatus displayed the most complex. In addition, hair-cell densities at sites sampled along the rostro-caudal axis of the saccular epithelia correlated with the observed patterns of arborization. PMID:23991887

  1. Tumor cell entry into the lymph node is controlled by CCL1 chemokine expressed by lymph node lymphatic sinuses

    PubMed Central

    Das, Suvendu; Sarrou, Eliana; Podgrabinska, Simona; Cassella, Melanie; Mungamuri, Sathish Kumar; Feirt, Nikki; Gordon, Ronald; Nagi, Chandandeep S.; Wang, Yarong; Entenberg, David; Condeelis, John

    2013-01-01

    Lymphatic vessels are thought to contribute to metastasis primarily by serving as a transportation system. It is widely believed that tumor cells enter lymph nodes passively by the flow of lymph. We demonstrate that lymph node lymphatic sinuses control tumor cell entry into the lymph node, which requires active tumor cell migration. In human and mouse tissues, CCL1 protein is detected in lymph node lymphatic sinuses but not in the peripheral lymphatics. CCR8, the receptor for CCL1, is strongly expressed by human malignant melanoma. Tumor cell migration to lymphatic endothelial cells (LECs) in vitro is inhibited by blocking CCR8 or CCL1, and recombinant CCL1 promotes migration of CCR8+ tumor cells. The proinflammatory mediators TNF, IL-1β, and LPS increase CCL1 production by LECs and tumor cell migration to LECs. In a mouse model, blocking CCR8 with the soluble antagonist or knockdown with shRNA significantly decreased lymph node metastasis. Notably, inhibition of CCR8 led to the arrest of tumor cells in the collecting lymphatic vessels at the junction with the lymph node subcapsular sinus. These data identify a novel function for CCL1–CCR8 in metastasis and lymph node LECs as a critical checkpoint for the entry of metastases into the lymph nodes. PMID:23878309

  2. Short-latency afferent inhibition determined by the sensory afferent volley.

    PubMed

    Bailey, Aaron Z; Asmussen, Michael J; Nelson, Aimee J

    2016-08-01

    Short-latency afferent inhibition (SAI) is characterized by the suppression of the transcranial magnetic stimulation motor evoked potential (MEP) by the cortical arrival of a somatosensory afferent volley. It remains unknown whether the magnitude of SAI reflects changes in the sensory afferent volley, similar to that observed for somatosensory evoked potentials (SEPs). The present study investigated stimulus-response relationships between sensory nerve action potentials (SNAPs), SAI, and SEPs and their interrelatedness. Experiment 1 (n = 23, age 23 ± 1.5 yr) investigated the stimulus-response profile for SEPs and SAI in the flexor carpi radialis muscle after stimulation of the mixed median nerve at the wrist using ∼25%, 50%, 75%, and 100% of the maximum SNAP and at 1.2× and 2.4× motor threshold (the latter equated to 100% of the maximum SNAP). Experiment 2 (n = 20, age 23.1 ± 2 yr) probed SEPs and SAI stimulus-response relationships after stimulation of the cutaneous digital nerve at ∼25%, 50%, 75%, and 100% of the maximum SNAP recorded at the elbow. Results indicate that, for both nerve types, SAI magnitude is dependent on the volume of the sensory afferent volley and ceases to increase once all afferent fibers within the nerve are recruited. Furthermore, for both nerve types, the magnitudes of SAI and SEPs are related such that an increase in excitation within somatosensory cortex is associated with an increase in the magnitude of afferent-induced MEP inhibition. PMID:27226451

  3. Lymphatic drainage in patients after replantation of extremities

    SciTech Connect

    Smith, A.R.; van Alphen, W.A.; van der Pompe, W.B.

    1987-02-01

    Lymph drainage was studied by means of lymph scintigraphy in eight patients in whom successful replantation of a totally or subtotally amputated extremity had been performed. Scintigrams were made after subcutaneous injection of technetium-99m in the replanted part of the patient and the contralateral, normal extremity. In all scintigrams, axillary or inguinal lymph node activity is seen, implying drainage of lymph by means of the lymph vessels. Retention of colloid in the replanted part (79 to 94 percent) shows no significant difference with the contralateral, normal side (86 to 94 percent). Unquestionable evidence of regeneration of lymphatics in humans is delivered in the three patients, in whom lymph node activity and normal retention percentages are seen on the scintigrams after total amputation of an extremity followed by replantation without anastomosing of interrupted lymph vessels.

  4. Immune cells control skin lymphatic electrolyte homeostasis and blood pressure.

    PubMed

    Wiig, Helge; Schröder, Agnes; Neuhofer, Wolfgang; Jantsch, Jonathan; Kopp, Christoph; Karlsen, Tine V; Boschmann, Michael; Goss, Jennifer; Bry, Maija; Rakova, Natalia; Dahlmann, Anke; Brenner, Sven; Tenstad, Olav; Nurmi, Harri; Mervaala, Eero; Wagner, Hubertus; Beck, Franz-Xaver; Müller, Dominik N; Kerjaschki, Dontscho; Luft, Friedrich C; Harrison, David G; Alitalo, Kari; Titze, Jens

    2013-07-01

    The skin interstitium sequesters excess Na+ and Cl- in salt-sensitive hypertension. Mononuclear phagocyte system (MPS) cells are recruited to the skin, sense the hypertonic electrolyte accumulation in skin, and activate the tonicity-responsive enhancer-binding protein (TONEBP, also known as NFAT5) to initiate expression and secretion of VEGFC, which enhances electrolyte clearance via cutaneous lymph vessels and increases eNOS expression in blood vessels. It is unclear whether this local MPS response to osmotic stress is important to systemic blood pressure control. Herein, we show that deletion of TonEBP in mouse MPS cells prevents the VEGFC response to a high-salt diet (HSD) and increases blood pressure. Additionally, an antibody that blocks the lymph-endothelial VEGFC receptor, VEGFR3, selectively inhibited MPS-driven increases in cutaneous lymphatic capillary density, led to skin Cl- accumulation, and induced salt-sensitive hypertension. Mice overexpressing soluble VEGFR3 in epidermal keratinocytes exhibited hypoplastic cutaneous lymph capillaries and increased Na+, Cl-, and water retention in skin and salt-sensitive hypertension. Further, we found that HSD elevated skin osmolality above plasma levels. These results suggest that the skin contains a hypertonic interstitial fluid compartment in which MPS cells exert homeostatic and blood pressure-regulatory control by local organization of interstitial electrolyte clearance via TONEBP and VEGFC/VEGFR3-mediated modification of cutaneous lymphatic capillary function. PMID:23722907

  5. Junb controls lymphatic vascular development in zebrafish via miR-182

    PubMed Central

    Kiesow, Kristin; Bennewitz, Katrin; Miranda, Laura Gutierrez; Stoll, Sandra J.; Hartenstein, Bettina; Angel, Peter; Kroll, Jens; Schorpp-Kistner, Marina

    2015-01-01

    JUNB, a subunit of the AP-1 transcription factor complex, mediates gene regulation in response to a plethora of extracellular stimuli. Previously, JUNB was shown to act as a critical positive regulator of blood vessel development and homeostasis as well as a negative regulator of proliferation, inflammation and tumour growth. Here, we demonstrate that the oncogenic miR-182 is a novel JUNB target. Loss-of-function studies by morpholino-mediated knockdown and the CRISPR/Cas9 technology identify a novel function for both JUNB and its target miR-182 in lymphatic vascular development in zebrafish. Furthermore, we show that miR-182 attenuates foxo1 expression indicating that strictly balanced Foxo1 levels are required for proper lymphatic vascular development in zebrafish. In conclusion, our findings uncover with the Junb/miR-182/Foxo1 regulatory axis a novel key player in governing lymphatic vascular morphogenesis in zebrafish. PMID:26458334

  6. Near-infrared fluorescence imaging of lymphatics in head and neck lymphedema

    NASA Astrophysics Data System (ADS)

    Tan, I.-Chih; Maus, Erik A.; Rasmussen, John C.; Marshall, Milton V.; Fife, Caroline E.; Smith, Latisha A.; Sevick-Muraca, Eva M.

    2011-03-01

    Treatment of lymphatic disease is complicated and controversial, due in part to the limited understanding of the lymphatic system. Lymphedema (LE) is a frequent complication after surgical resection and radiation treatment in cancer survivors, and is especially debilitating in regions where treatment options are limited. Although some extremity LE can be effectively treated with manual lymphatic drainage (MLD) therapy or compression devices to direct proximal lymph transport, head and neck LE is more challenging, due to complicated geometry and complex lymphatic structure in head and neck region. Herein, we describe the compassionate use of an investigatory technique of near-infrared (NIR) fluorescence imaging to understand the lymphatic anatomy and function, and to help direct MLD in a patient with head and neck LE. Immediately after 9 intradermal injections of 25 μg indocyanine green each around the face and neck region, NIR fluorescence images were collected using a custom-built imaging system with diffused excitation light illumination. These images were then used to direct MLD therapy. In addition, 3-dimensional (3D) surface profilometry was used to monitor response to therapy. NIR fluorescence images of functioning lymphatic vessels and abnormal structures were obtained. Precise geometries of facial structures were obtained using 3D profilometry, and detection of small changes in edema between therapy sessions was achieved. NIR fluorescence imaging provides a mapping of lymphatic architecture to direct MLD therapy and thus improve treatment efficacy in the head and neck LE, while 3D profilometry allowed longitudinal assessment of edema to evaluate the efficacy of therapy.

  7. Isolation and characterization of lymphatic endothelial cells from human glossal lymphangioma.

    PubMed

    You, Lanying; Wu, Mingfu; Chen, Ying; Xu, Gang; Wei, Juncheng; Li, Qiong; Song, Anping; Zhao, Liangpin; Li, Shuang; Han, Zhiqiang; Zhou, Jianfeng; Lu, Yunpin; Wang, Shixuan; Ma, Ding; Meng, Li

    2010-01-01

    Abnormal lymphangiogenesis is associated with several diseases such as tumor metastasis and lymphangioma. Human lymphangioma originated from the transformation of lymphatic endothelium is a benign malformation of lymphatic vessels and its pathogenesis has up to date not been illuminated and its cell model has also not been established. An optimized method was used to isolate lymphatic endothelial cells from human glossal lymphangioma (GL-LECs) and GL-LECs were further primarily cultured and expanded. GL-LECs were of typical cobblestone appearance when they reached confluence. The weible-palade body was observed in the GL-LECs cytoplasm. Almost all GL-LECs were strongly positive for specific lymphatic markers FLT-4, LYVE-1 and prox-1 by immunocytochemistry. Furthermore, three-dimension tube-like capillaries of GL-LECs resembled the lymphatic system in vivo, and the GL-LECs spheroids sprouted radically out to form three-dimensional buds when embedded in the cultured BME. These results indicated that high purity GL-LECs were successfully isolated and expanded. They had the abilities of tube formation and differentiation in vitro, which provide a favorable cell model for further uncovering the pathogenesis of human lymphangiomas.

  8. Lymphatic drainage of the liver and its implications in the management of colorectal cancer liver metastases.

    PubMed

    Lupinacci, Renato Micelli; Paye, François; Coelho, Fabricio Ferreira; Kruger, Jaime Arthur Pirolla; Herman, Paulo

    2014-12-01

    The liver is the most common site of distant metastases in patients with colorectal cancer. Surgery represents the mainstream for curative treatment of colorectal cancer liver metastases (CRCLM) with long-term survival up to 58 and 36 % at 5 and 10 years, respectively. Despite advances on diagnosis, staging and surgical strategies, 60-70 % of patients will develop recurrence of the disease even after R0 resection of CRCLM. Tumor staging, prognosis, and therapeutic approaches for cancer are most often based on the extent of involvement of regional lymph nodes (LNs) and, to a lesser extent, on the invasion of regional lymphatic vessels draining the primary tumor. For CRCLM, the presence of intra hepatic lymphatic and blood vascular dissemination has been associated with an increased risk of intra hepatic recurrence, poorer disease-free and overall survival after liver resection. Also, several studies have reviewed the role of surgery in the patient with concomitant CRCLM and liver pedicle LN metastasis. Although pedicle LN involvement is related to worst survival rates, it does not differentiate patients that will relapse from those that will not. This review aims to briefly describe the anatomy of the liver's lymphatic drainage, the incidence of intrahepatic lymphatic invasion and hilar lymph node involvement, as well as their clinical impact in CRCLM. A better understanding of the role of liver lymphatic metastasis might, in the near future, impact the strategy of systemic therapies after liver resection as for primary colorectal tumors.

  9. Pain processing by spinal microcircuits: afferent combinatorics.

    PubMed

    Prescott, Steven A; Ratté, Stéphanie

    2012-08-01

    Pain, itch, heat, cold, and touch represent different percepts arising from somatosensory input. How stimuli give rise to these percepts has been debated for over a century. Recent work supports the view that primary afferents are highly specialized to transduce and encode specific stimulus modalities. However, cross-modal interactions (e.g. inhibition or exacerbation of pain by touch) support convergence rather than specificity in central circuits. We outline how peripheral specialization together with central convergence could enable spinal microcircuits to combine inputs from distinctly specialized, co-activated afferents and to modulate the output signals thus formed through computations like normalization. These issues will be discussed alongside recent advances in our understanding of microcircuitry in the superficial dorsal horn.

  10. Pain processing by spinal microcircuits: afferent combinatorics.

    PubMed

    Prescott, Steven A; Ratté, Stéphanie

    2012-08-01

    Pain, itch, heat, cold, and touch represent different percepts arising from somatosensory input. How stimuli give rise to these percepts has been debated for over a century. Recent work supports the view that primary afferents are highly specialized to transduce and encode specific stimulus modalities. However, cross-modal interactions (e.g. inhibition or exacerbation of pain by touch) support convergence rather than specificity in central circuits. We outline how peripheral specialization together with central convergence could enable spinal microcircuits to combine inputs from distinctly specialized, co-activated afferents and to modulate the output signals thus formed through computations like normalization. These issues will be discussed alongside recent advances in our understanding of microcircuitry in the superficial dorsal horn. PMID:22409855

  11. The left-right Pitx2 pathway drives organ-specific arterial and lymphatic development in the intestine

    PubMed Central

    Mahadevan, Aparna; Welsh, Ian C.; Sivakumar, Aravind; Gludish, David W.; Shilvock, Abigail R.; Noden, Drew M.; Kurpios, Natasza A.

    2015-01-01

    SUMMARY The dorsal mesentery (DM) is the major conduit for blood and lymphatic vessels in the gut. The mechanisms underlying their morphogenesis are challenging to study and remain unknown. Here we show that arteriogenesis in the DM begins during gut rotation and proceeds strictly on the left side, dependent on the Pitx2 target gene Cxcl12. Although competent Cxcr4-positive angioblasts are present on the right, they fail to form vessels and progressively emigrate. Surprisingly, gut lymphatics also initiate in the left DM and arise only after – and dependent on – arteriogenesis, implicating arteries as drivers of gut lymphangiogenesis. Our data begin to unravel the origin of two distinct vascular systems and demonstrate how early L-R molecular asymmetries are translated into organ-specific vascular patterns. We propose a dual origin of gut lymphangiogenesis, where prior arterial growth is required to initiate local lymphatics that only subsequently connect to the vascular system. PMID:25482882

  12. Blockage of vibrissae afferents: I. Motor effects.

    PubMed

    Prchal, A; Albarracín, A L; Décima, E E

    2004-02-01

    In the past, it has been proposed that the rat vibrissae play an important role in other hand, postural abnormalities, muscle tone decreases and hypomotility after sensory organ destructions were proposed as evidence supporting the "level setting" or "tonic" hypothesis. This hypothesis postulates that afferent activity, besides its well know transductive functions, sets the excitability state of the central nervous system. We thought the vibrissal system to be a good model to dissect these two postulated roles because vibrissae trimming would annul the transductive function without affecting the integrity of nerve activity. Thus we compare the effects of trimming the whiskers with blocking the vibrissal afferent nerves on two types of motor behavior: activity in an open field and walking over a rope connecting two elevated platforms. We found that only vibrissal afferent blockage (both nerve section and local anaesthesia) produced severe failures in the motor performances studied. These effects could not be fully explained by the abolition of the vibrissae as a sensory modality because cutting the whiskers did not significantly affect the motor performance. These data are discussed in reference to a tonic or general excitatory function of sensory inputs upon the central nervous system. PMID:15143620

  13. MT1-MMP sheds LYVE-1 on lymphatic endothelial cells and suppresses VEGF-C production to inhibit lymphangiogenesis

    PubMed Central

    Wong, Hoi Leong Xavier; Jin, Guoxiang; Cao, Renhai; Zhang, Shuo; Cao, Yihai; Zhou, Zhongjun

    2016-01-01

    Lymphangiogensis is involved in various pathological conditions, such as arthritis and cancer metastasis. Although many factors have been identified to stimulate lymphatic vessel growth, little is known about lymphangiogenesis inhibitors. Here we report that membrane type 1-matrix metalloproteinase (MT1-MMP) is an endogenous suppressor of lymphatic vessel growth. MT1-MMP-deficient mice exhibit spontaneous corneal lymphangiogenesis without concomitant changes in angiogenesis. Mice lacking MT1-MMP in either lymphatic endothelial cells or macrophages recapitulate corneal lymphangiogenic phenotypes observed in Mmp14−/− mice, suggesting that the spontaneous lymphangiogenesis is both lymphatic endothelial cells autonomous and macrophage associated. Mechanistically, MT1-MMP directly cleaves LYVE-1 on lymphatic endothelial cells to inhibit LYVE-1-mediated lymphangiogenic responses. In addition, MT1-MMP-mediated PI3Kδ signalling restrains the production of VEGF-C from prolymphangiogenic macrophages through repressing the activation of NF-κB signalling. Thus, we identify MT1-MMP as an endogenous inhibitor of physiological lymphangiogenesis. PMID:26926389

  14. Aging-related anatomical and biochemical changes in lymphatic collectors impair lymph transport, fluid homeostasis, and pathogen clearance

    PubMed Central

    Zolla, Valerio; Nizamutdinova, Irina Tsoy; Scharf, Brian; Clement, Cristina C; Maejima, Daisuke; Akl, Tony; Nagai, Takashi; Luciani, Paola; Leroux, Jean-Christophe; Halin, Cornelia; Stukes, Sabriya; Tiwari, Sangeeta; Casadevall, Arturo; Jacobs, William R; Entenberg, David; Zawieja, David C; Condeelis, John; Fooksman, David R; Gashev, Anatoliy A; Santambrogio, Laura

    2015-01-01

    The role of lymphatic vessels is to transport fluid, soluble molecules, and immune cells to the draining lymph nodes. Here, we analyze how the aging process affects the functionality of the lymphatic collectors and the dynamics of lymph flow. Ultrastructural, biochemical, and proteomic analysis indicates a loss of matrix proteins, and smooth muscle cells in aged collectors resulting in a decrease in contraction frequency, systolic lymph flow velocity, and pumping activity, as measured in vivo in lymphatic collectors. Functionally, this impairment also translated into a reduced ability for in vivo bacterial transport as determined by time-lapse microscopy. Ultrastructural and proteomic analysis also indicates a decrease in the thickness of the endothelial cell glycocalyx and loss of gap junction proteins in aged lymph collectors. Redox proteomic analysis mapped an aging-related increase in the glycation and carboxylation of lymphatic’s endothelial cell and matrix proteins. Functionally, these modifications translate into apparent hyperpermeability of the lymphatics with pathogen escaping from the collectors into the surrounding tissue and a decreased ability to control tissue fluid homeostasis. Altogether, our data provide a mechanistic analysis of how the anatomical and biochemical changes, occurring in aged lymphatic vessels, compromise lymph flow, tissue fluid homeostasis, and pathogen transport. PMID:25982749

  15. Lymphatic Filariasis: Frequently Asked Questions (FAQs)

    MedlinePlus

    ... a parasitic disease caused by microscopic, thread-like worms. The adult worms only live in the human lymph system. The ... South America. You cannot get infected with the worms in the United States. How is lymphatic filariasis ...

  16. Afferent innervation patterns of the saccule in pigeons

    NASA Technical Reports Server (NTRS)

    Zakir, M.; Huss, D.; Dickman, J. D.

    2003-01-01

    The innervation patterns of vestibular saccular afferents were quantitatively investigated in pigeons using biotinylated dextran amine as a neural tracer and three-dimensional computer reconstruction. Type I hair cells were found throughout a large portion of the macula, with the highest density observed in the striola. Type II hair cells were located throughout the macula, with the highest density in the extrastriola. Three classes of afferent innervation patterns were observed, including calyx, dimorph, and bouton units, with 137 afferents being anatomically reconstructed and used for quantitative comparisons. Calyx afferents were located primarily in the striola, innervated a number of type I hair cells, and had small innervation areas. Most calyx afferent terminal fields were oriented parallel to the anterior-posterior axis and the morphological polarization reversal line. Dimorph afferents were located throughout the macula, contained fewer type I hair cells in a calyceal terminal than calyx afferents and had medium sized innervation areas. Bouton afferents were restricted to the extrastriola, with multi-branching fibers and large innervation areas. Most of the dimorph and bouton afferents had innervation fields that were oriented dorso-ventrally but were parallel to the neighboring reversal line. The organizational morphology of the saccule was found to be distinctly different from that of the avian utricle or lagena otolith organs and appears to represent a receptor organ undergoing evolutionary adaptation toward sensing linear motion in terrestrial and aerial species.

  17. CT demonstration of perirenal lymphatic cysts.

    PubMed

    De Maeyer, P; Baert, A L; Usewils, R; Wynants, P; De Pauw, A

    1982-01-01

    A case of perirenal lymphatic cysts demonstrated by computed tomography is reported. These lymphatic cysts, a histological subtype of lymphangiomata, are clearly visible as collections with clear fluid-type density surrounding both kidneys. The retroperitoneal localization of this rarity has been reported in the radiological literature, whereas, to our knowledge, the radiological demonstration of the perirenal localization has not. CT provides a unique method for direct radiological visualization of the cyst.

  18. Lymphatic endothelial cells support tumor growth in breast cancer

    PubMed Central

    Lee, Esak; Pandey, Niranjan B.; Popel, Aleksander S.

    2014-01-01

    Tumor lymphatic vessels (LV) serve as a conduit of tumor cell dissemination, due to their leaky nature and secretion of tumor-recruiting factors. Though lymphatic endothelial cells (LEC) lining the LV express distinct factors (also called lymphangiocrine factors), these factors and their roles in the tumor microenvironment are not well understood. Here we employ LEC, microvascular endothelial cells (MEC), and human umbilical vein endothelial cells (HUVEC) cultured in triple-negative MDA-MB-231 tumor-conditioned media (TCM) to determine the factors that may be secreted by various EC in the MDA-MB-231 breast tumor. These factors will serve as endothelium derived signaling molecules in the tumor microenvironment. We co-injected these EC with MDA-MB-231 breast cancer cells into animals and showed that LEC support tumor growth, HUVEC have no significant effect on tumor growth, whereas MEC suppress it. Focusing on LEC-mediated tumor growth, we discovered that TCM-treated LEC (‘tumor-educated LEC') secrete high amounts of EGF and PDGF-BB, compared to normal LEC. LEC-secreted EGF promotes tumor cell proliferation. LEC-secreted PDGF-BB induces pericyte infiltration and angiogenesis. These lymphangiocrine factors may support tumor growth in the tumor microenvironment. This study shows that LV serve a novel role in the tumor microenvironment apart from their classical role as conduits of metastasis. PMID:25068296

  19. Label free in vivo laser speckle imaging of blood and lymph vessels

    NASA Astrophysics Data System (ADS)

    Kalchenko, Vyacheslav; Kuznetsov, Yuri; Meglinski, Igor; Harmelin, Alon

    2012-05-01

    The peripheral lymphatic vascular system is a part of the immune body system comprising a complex network of lymph vessels and nodes that are flowing lymph toward the heart. Traditionally the imaging of lymphatic vessels is based on the conventional imaging modalities utilizing contrast fluorescence materials. Given the important role of the lymphatic system there is a critical need for the development of noninvasive imaging technologies for functional quantitative diagnosis of the lymph vessels and lymph flow without using foreign chemicals. We report a label free methodology for noninvasive in vivo imaging of blood and lymph vessels, using long-exposure laser speckle imaging approach. This approach entails great promise in the noninvasive studies of tissues blood and lymph vessels distribution in vivo.

  20. Advances in Lymphatic Imaging and Drug Delivery

    SciTech Connect

    Nune, Satish K.; Gunda, Padmaja; Majeti, Bharat K.; Thallapally, Praveen K.; Laird, Forrest M.

    2011-09-10

    Cancer remains the second leading cause of death after heart disease in the US. While metastasized cancers such as breast, prostate, and colon are incurable, before their distant spread, these diseases will have invaded the lymphatic system as a first step in their progression. Hence, proper evaluation of the disease state of the lymphatics which drain a tumor site is crucial to staging and the formation of a treatment plan. Current lymphatic imaging modalities with visible dyes and radionucleotide tracers offer limited sensitivity and poor resolution; however, newer tools using nanocarriers, quantum dots, and magnetic resonance imaging promise to vastly improve the staging of lymphatic spread without needless biopsies. Concurrent with the improvement of lymphatic imaging agents, has been the development of drug carriers that can localize chemotherapy to the lymphatic system, thus improving the treatment of localized disease while minimizing the exposure of healthy organs to cytotoxic drugs. This review will focus on polymeric systems that have been developed for imaging and drug delivery to the lymph system, how these new devices improve upon current technologies, and where further improvement is needed.

  1. Angiogenesis of lung cancer utilizes existing blood vessels rather than developing new vessels using signals from carcinogenesis.

    PubMed

    Uramoto, Hidetaka; Yamada, Sohsuke; Tanaka, Fumihiro

    2013-05-01

    Cancer cells metastasize via angiogenesis and are a long-standing therapeutic target in malignant tumors. Vascular endothelial growth factor (VEGF) antibodies have been developed for clinical use, with limited benefits. Therefore, identifying the underlying mechanisms of angiogenesis regarding whether tumor vessels are derived from cancer cells or blood vessels in existence, is highly anticipated. Recently, epidermal growth factor receptor (EGFR) antibodies were utilized to detect cancer cells with somatic mutations of EGFR. The concordance rate is high for detection between immunohistochemical staining and polymerase chain reaction (PCR)-based methods. We hypothesized that endothelial cells exhibiting lymphatic and venous tumor invasiveness will be immunoreactive if new blood vessels are derived from the lung cancer itself, because EGFR mutations occur at a relatively early phase in carcinogenesis. We examined endothelial cells with EGFR mutations exhibiting lymphatic and venous tumor invasiveness using these antibodies. Tumor samples were obtained from 848 consecutive patients with lung cancer. Among 153 of 595 adenocarcinomas with EGFR-sensitive mutations, the number of lymphatic and venous invasive tumors was 35 and 19, respectively. Consequently, 12 available tumor specimens (five specimens for delE746-A750 and seven specimens for L858R) with both factors were evaluated. The main cancer cells were highly immunoreactive; however, no obvious lesions were detected with endothelial cells exhibiting lymphatic or venous invasiveness. Therefore, the angiogenesis of lung cancer seems to utilize blood vessels in existence, rather than create new vessels using signals from carcinogenesis.

  2. Artificial lymphatic drainage systems for vascularized microfluidic scaffolds.

    PubMed

    Wong, Keith H K; Truslow, James G; Khankhel, Aimal H; Chan, Kelvin L S; Tien, Joe

    2013-08-01

    The formation of a stably perfused microvasculature continues to be a major challenge in tissue engineering. Previous work has suggested the importance of a sufficiently large transmural pressure in maintaining vascular stability and perfusion. Here we show that a system of empty channels that provides a drainage function analogous to that of lymphatic microvasculature in vivo can stabilize vascular adhesion and maintain perfusion rate in dense, hydraulically resistive fibrin scaffolds in vitro. In the absence of drainage, endothelial delamination increased as scaffold density increased from 6 to 30 mg/mL and scaffold hydraulic conductivity decreased by a factor of 20. Single drainage channels exerted only localized vascular stabilization, the extent of which depended on the distance between vessel and drainage as well as scaffold density. Computational modeling of these experiments yielded an estimate of 0.40-1.36 cm H2O for the minimum transmural pressure required for vascular stability. We further designed and constructed fibrin patches (0.8 × 0.9 cm(2)) that were perfused by a parallel array of vessels and drained by an orthogonal array of drainage channels; only with the drainage did the vessels display long-term stability and perfusion. This work underscores the importance of drainage in vascularization, especially when a dense, hydraulically resistive scaffold is used. PMID:23281125

  3. Identification of Different Types of Spinal Afferent Nerve Endings That Encode Noxious and Innocuous Stimuli in the Large Intestine Using a Novel Anterograde Tracing Technique

    PubMed Central

    Spencer, Nick J.; Kyloh, Melinda; Duffield, Michael

    2014-01-01

    In mammals, sensory stimuli in visceral organs, including those that underlie pain perception, are detected by spinal afferent neurons, whose cell bodies lie in dorsal root ganglia (DRG). One of the major challenges in visceral organs has been how to identify the different types of nerve endings of spinal afferents that transduce sensory stimuli into action potentials. The reason why spinal afferent nerve endings have been so challenging to identify is because no techniques have been available, until now, that can selectively label only spinal afferents, in high resolution. We have utilized an anterograde tracing technique, recently developed in our laboratory, which facilitates selective labeling of only spinal afferent axons and their nerve endings in visceral organs. Mice were anesthetized, lumbosacral DRGs surgically exposed, then injected with dextran-amine. Seven days post-surgery, the large intestine was removed. The characteristics of thirteen types of spinal afferent nerve endings were identified in detail. The greatest proportion of nerve endings was in submucosa (32%), circular muscle (25%) and myenteric ganglia (22%). Two morphologically distinct classes innervated myenteric ganglia. These were most commonly a novel class of intraganglionic varicose endings (IGVEs) and occasionally rectal intraganglionic laminar endings (rIGLEs). Three distinct classes of varicose nerve endings were found to innervate the submucosa and circular muscle, while one class innervated internodal strands, blood vessels, crypts of lieberkuhn, the mucosa and the longitudinal muscle. Distinct populations of sensory endings were CGRP-positive. We present the first complete characterization of the different types of spinal afferent nerve endings in a mammalian visceral organ. The findings reveal an unexpectedly complex array of different types of primary afferent endings that innervate specific layers of the large intestine. Some of the novel classes of nerve endings identified

  4. Measurement of lymphatic function with technetium-99m-labelled polyclonal immunoglobulin.

    PubMed

    Svensson, W; Glass, D M; Bradley, D; Peters, A M

    1999-05-01

    A reliable method for measuring lymph flow in physiological units would be valuable, especially in conditions in which it is uncertain whether lymph flow is increased or decreased. The requirements of a radiopharmaceutical for such measurement include stable radionuclide labelling and rapid access to lymphatic vessels following tissue injection but no access to blood vessels. A soluble macromolecule is likely to come closest to meeting these requirements. Technetium-99m-labelled human polyclonal immunoglobulin (HIG) was therefore investigated firstly in comparison with 99mTc-labelled human serum albumin (HSA) in patients undergoing routine lymphoscintigraphy and secondly with respect to injection site in a group of volunteers with post-mastectomy oedema (PMO). Subcutaneous injection of 99mTc-HIG into the web space of a distal extremity gave images in which lymphatic vessels were more clearly defined compared with images obtained after injection of 99mTc-HSA. Lymph nodes were also more clearly defined, suggesting specific retention of HIG, possibly through Fc-mediated binding. Peripheral blood sampling showed a delayed arrival in blood of radioactivity after 99mTc-HIG compared with 99mTc-HSA, although ultimately, the blood recovery of 99mTc-HIG was significantly higher (P < 0.05) than that of 99mTc-HSA. Clearance rates of radioactivity from the injection site were not significantly different, however, between the two agents. In patients with PMO, web space injection of 99mTc-HIG gave excellent images of normal lymphatic vessels, of lymph nodes and of abnormal lymph drainage such as dermal backflow in swollen arms. In contrast, neither lymphatic vessels nor lymph nodes were visualised after injection into the skin of the dorsum of the distal forearm. Although there was no difference in clearance rates from the injection sites between normal and swollen arms with either agent in PMO, clearance was significantly faster following injection into the web space (0.11% per

  5. Blood vessels, circulation and blood pressure.

    PubMed

    Hendry, Charles; Farley, Alistair; McLafferty, Ella

    This article, which forms part of the life sciences series, describes the vessels of the body's blood and lymphatic circulatory systems. Blood pressure and its regulatory systems are examined. The causes and management of hypertension are also explored. It is important that nurses and other healthcare professionals understand the various mechanisms involved in the regulation of blood pressure to prevent high blood pressure or ameliorate its damaging consequences.

  6. Monitoring of small lymphatics function under different impact on animal model by integrated optical imaging

    NASA Astrophysics Data System (ADS)

    Galanzha, Ekaterina I.; Tuchin, Valery V.; Chowdhury, Parimal; Zharov, Vladimir P.

    2004-08-01

    The digital transmission microscopy is very informative, noninvasive for vessels, simple and available method for studying and measuring lymph microvessels function in vivo. Rat mesentery can use as promising animal model of lymph microvessels in vivo. Such imaging system allowed visualizing the entire lymphangion (with input and output valves), its wall, lymphatic valves, lymph flow as well as single cells in flow; obtaining anew basic information on lymph microcirculation and quantitative data on lymphatic function including indexes of phasic contractions and valve function, the quantitative parameters of lymph-flow velocity. Rat mesentery is good model to create different types of lymphedemas in acute and chronic experiments. The obtained data revealed that significant edema started immediately after lymph node dissection in one-half of cases and was accompanied by lymphatic disturbances. The greatest degree of edema was found after 1 week. After 4 weeks, the degree of edema sometimes decreased, but functional lymphatic disturbances progressed. Nicotine had significant direct dose-dependent effect on microlymphatic function at the acute local application, but the same dose of this drug was not effect on microcirculation in chronic intoxication. Despite yielding interesting data, transmittance microscopy had some limitations when applied to microcirculation studies. The problems could be solved at the application of integrated measuring technique.

  7. Response properties of pigeon otolith afferents to linear acceleration

    NASA Technical Reports Server (NTRS)

    Si, X.; Angelaki, D. E.; Dickman, J. D.

    1997-01-01

    In the present study, the sensitivity to sinusoidal linear accelerations in the plane of the utricular macula was tested in afferents. The head orientation relative to the translation axis was varied in order to determine the head position that elicited the maximal and minimal responses for each afferent. The response gain and phase values obtained to 0.5-Hz and 2-Hz linear acceleration stimuli were then plotted as a function of head orientation and a modified cosine function was fit to the data. From the best-fit cosine function, the predicted head orientations that would produce the maximal and minimal response gains were estimated. The estimated maximum response gains to linear acceleration in the utricular plane for the afferents varied between 75 and 1420 spikes s-1 g-1. The mean maximal gains for all afferents to 0.5-Hz and 2-Hz sinusoidal linear acceleration stimuli were 282 and 367 spikes s-1 g-1, respectively. The minimal response gains were essentially zero for most units. The response phases always led linear acceleration and remained constant for each afferent, regardless of head orientation. These response characteristics indicate that otolith afferents are cosine tuned and behave as one-dimensional linear accelerometers. The directions of maximal sensitivity to linear acceleration for the afferents varied throughout the plane of the utricle; however, most vectors were directed out of the opposite ear near the interaural axis. The response dynamics of the afferents were tested using stimulus frequencies ranging between 0.25 Hz and 10 Hz (0.1 g peak acceleration). Across stimulus frequencies, most afferents had increasing gains and constant phase values. These dynamic properties for individual afferents were fit with a simple transfer function that included three parameters: a mechanical time constant, a gain constant, and a fractional order distributed adaptation operator.

  8. Effect of Microgravity on Afferent Innervation

    NASA Technical Reports Server (NTRS)

    1998-01-01

    Presentations and publications are: (1) an audiovisual summary web presentation on results from SLM-MIR avian experiments. A color presentation summarizing results from the SLM-MIR and STS-29 avian experiments; (2) color threshold and ratio of S 100B MAP5, NF68/200, GABA and GAD; (3) chicken (Gallus domesticus) inner ear afferents; (4) microgravity in the STS-29 Space Shuttle Discovery affected the vestibular system of chick embryos; (5) expression of S 100B in sensory and secretory cells of the vertebrate inner ear; (6) otoconia biogenesis, phylogeny, composition and functional attributes;(7) the glycan keratin sulfate in inner ear crystals; (8) elliptical-P cells in the avian perilymphatic interface of the tegmentum vasculosum; and (9) LAMP2c and S100B upregulation in brain stem after VIIIth nerve deafferentation.

  9. Chicken (Gallus domesticus) inner ear afferents

    NASA Technical Reports Server (NTRS)

    Hara, H.; Chen, X.; Hartsfield, J. F.; Hara, J.; Martin, D.; Fermin, C. D.

    1998-01-01

    Neurons from the vestibular (VG) and the statoacoustic (SAG) ganglion of the chick (Gallus domesticus) were evaluated histologically and morphometrically. Embryos at stages 34 (E8 days), 39 (E13 days) and 44 (E18 days) were sacrificed and temporal bones microdissected. Specimens were embedded in JB-4 methacrylate plastic, and stained with a mixture of 0.2% toluidine blue (TB) and 0.1% basic Fuschin in 25% ethanol or with a mixture of 2% TB and 1% paraphenylenediamine (PDA) for axon and myelin measurement study. Images of the VIIIth nerve were produced by a V150 (R) color imaging system and the contour of 200-300 neuronal bodies (perikarya) was traced directly on a video screen with a mouse in real time. The cross-sectional area of VG perikarya was 67.29 micrometers2 at stage 34 (E8), 128.46 micrometers2 at stage 39 (E13) and 275.85 micrometers2 at stage 44 (E18). The cross-sectional area of SAG perikarya was 62.44 micrometers2 at stage 34 (E8), 102.05 micrometers2 at stage 39 (E13) and 165.02 micrometers2 at stage 44 (E18). A significant cross-sectional area increase of the VG perikarya between stage 39 (E13) and stage 44 (E18) was determined. We randomly measured the cross-sectional area of myelin and axoplasm of hatchling afferent nerves, and found a correspondence between axoplasmic and myelin cross-sectional area in the utricular, saccular and semicircular canal nerve branches of the nerve. The results suggest that the period between stage 34 (E8) and 39 (E13) is a critical period for afferent neuronal development. Physiological and behavioral vestibular properties of developing and maturing hatchlings may change accordingly. The results compliment previous work by other investigators and provide valuable anatomical measures useful to correlate physiological data obtained from stimulation of the whole nerve or its parts.

  10. Circadian variation in gastric vagal afferent mechanosensitivity.

    PubMed

    Kentish, Stephen J; Frisby, Claudine L; Kennaway, David J; Wittert, Gary A; Page, Amanda J

    2013-12-01

    Food intake is coordinated to cellular metabolism by clock gene expression with a master clock in the suprachiasmatic nucleus synchronized by light exposure. Gastric vagal afferents play a role in regulating food intake, but it is unknown whether they exhibit circadian variation in their mechanosensitivity. We aimed to determine whether gastric vagal afferents express clock genes and whether their response to mechanical stimuli oscillates throughout the light/dark cycle. Nodose ganglia were collected from 8-week-old female C57BL/6 mice every 3 h starting at lights off (1800 h) to quantify Bmal1, Per1, Per2, and Nr1d1 mRNA by qRT-PCR. Additionally in vitro single-fiber recordings of gastric vagal mechanoreceptors were taken at all time points. Per1, Per2, Bmal1, and Nr1d1 mRNA is expressed in the nodose ganglia and levels oscillated over a 24 h period. In mice fed ad libitum, gastric content was 3 times higher at 0000 h and 0300 h than 1200 h. The response of tension receptors to 3 g stretch was reduced by up to 70% at 2100 h, 0000 h, and 0300 h compared with 1200 h. Gastric mucosal receptor response to stroking with a 50 mg von Frey hair was 3 times greater at 1200 h and 1500 h than the response at 0000 h. Similar findings were obtained in mice fasted for 6 h or maintained in darkness for 3 d before study. Therefore, these changes do not result from food intake or the light/dark cycle. Thus, gastric vagal mechanoreceptors display circadian rhythm, which may act to control food intake differentially at different times of the day. PMID:24305819

  11. Unmyelinated type II afferent neurons report cochlear damage

    PubMed Central

    Liu, Chang; Glowatzki, Elisabeth; Fuchs, Paul Albert

    2015-01-01

    In the mammalian cochlea, acoustic information is carried to the brain by the predominant (95%) large-diameter, myelinated type I afferents, each of which is postsynaptic to a single inner hair cell. The remaining thin, unmyelinated type II afferents extend hundreds of microns along the cochlear duct to contact many outer hair cells. Despite this extensive arbor, type II afferents are weakly activated by outer hair cell transmitter release and are insensitive to sound. Intriguingly, type II afferents remain intact in damaged regions of the cochlea. Here, we show that type II afferents are activated when outer hair cells are damaged. This response depends on both ionotropic (P2X) and metabotropic (P2Y) purinergic receptors, binding ATP released from nearby supporting cells in response to hair cell damage. Selective activation of P2Y receptors increased type II afferent excitability by the closure of KCNQ-type potassium channels, a potential mechanism for the painful hypersensitivity (that we term “noxacusis” to distinguish from hyperacusis without pain) that can accompany hearing loss. Exposure to the KCNQ channel activator retigabine suppressed the type II fiber’s response to hair cell damage. Type II afferents may be the cochlea’s nociceptors, prompting avoidance of further damage to the irreparable inner ear. PMID:26553995

  12. Cerebral Lipiodol Embolism after Lymphatic Embolization for Plastic Bronchitis

    PubMed Central

    Kirschen, Matthew P.; Dori, Yoav; Itkin, Maxim; Licht, Daniel J.; Ichord, Rebecca; Vossough, Arastoo

    2016-01-01

    An adolescent with plastic bronchitis due to congenital heart disease had altered mental status after an interventional lymphatic procedure in which lipiodol contrast was used. Neuroimaging revealed cerebral lipiodol embolization due to direct shunting between lymphatic channels and pulmonary veins. Cerebral lipiodol embolization is a potential neurologic morbidity associated with interventional lymphatic procedures. PMID:27297208

  13. Personalized Therapy for Generalized Lymphatic Anomaly/Gorham-Stout Disease With a Combination of Sunitinib and Taxol.

    PubMed

    Rössler, Jochen; Saueressig, Ulrich; Kayser, Gian; von Winterfeld, Moritz; Klement, Gianoula L

    2015-11-01

    The recently revised ISSVA classification approved in Melbourne in April 2014 recognizes generalized lymphatic anomaly and lymphatic malformation in Gorham-Stout disease. The 2 entities can overlap in presentation, as both are characterized by destructive lymphatic vessel invasion of the axial skeleton and surrounding soft tissues. At least at present, no standard therapeutic options exist, and due to the rarity of the disease, no clinical trials are available. We present 2 patients, 1 with generalized lymphatic anomaly and 1 with lymphatic malformation in Gorham-Stout disease, with severe exacerbation during puberty. The first child presented in florid pulmonary failure and pleural effusion, the other with severe pain due to bone destruction of the pelvis and inability to walk. Both were treated using individualized protocols. The manuscript describes the rationale for choosing sunitinib in combination with low-dose (metronomic) taxol. Both patients experienced clinical and radiologic response without major toxicities, suggesting that patients with rare conditions may benefit from individualized, molecularly based therapies.

  14. Personalized Therapy for Generalized Lymphatic Anomaly/Gorham-Stout Disease With a Combination of Sunitinib and Taxol

    PubMed Central

    Rössler, Jochen; Saueressig, Ulrich; Kayser, Gian; von Winterfeld, Moritz

    2015-01-01

    The recently revised ISSVA classification approved in Melbourne in April 2014 recognizes generalized lymphatic anomaly and lymphatic malformation in Gorham-Stout disease. The 2 entities can overlap in presentation, as both are characterized by destructive lymphatic vessel invasion of the axial skeleton and surrounding soft tissues. At least at present, no standard therapeutic options exist, and due to the rarity of the disease, no clinical trials are available. We present 2 patients, 1 with generalized lymphatic anomaly and 1 with lymphatic malformation in Gorham-Stout disease, with severe exacerbation during puberty. The first child presented in florid pulmonary failure and pleural effusion, the other with severe pain due to bone destruction of the pelvis and inability to walk. Both were treated using individualized protocols. The manuscript describes the rationale for choosing sunitinib in combination with low-dose (metronomic) taxol. Both patients experienced clinical and radiologic response without major toxicities, suggesting that patients with rare conditions may benefit from individualized, molecularly based therapies. PMID:26458155

  15. Transcription factor COUP-TFII is indispensable for venous and lymphatic development in zebrafish and Xenopus laevis

    SciTech Connect

    Aranguren, Xabier L.; Beerens, Manu; Vandevelde, Wouter; Dewerchin, Mieke; Carmeliet, Peter; Luttun, Aernout

    2011-06-24

    Highlights: {yields} COUP-TFII deficiency in zebrafish affects arterio-venous EC specification. {yields} COUP-TFII is indispensable for lymphatic development in zebrafish. {yields} COUP-TFII knockdown in Xenopus disrupts lymphatic EC differentiation and migration. {yields} COUP-TFII's role in EC fate decisions is evolutionary conserved. -- Abstract: Transcription factors play a central role in cell fate determination. Gene targeting in mice revealed that Chicken Ovalbumin Upstream Promoter-Transcription Factor II (COUP-TFII, also known as Nuclear Receptor 2F2 or NR2F2) induces a venous phenotype in endothelial cells (ECs). More recently, NR2F2 was shown to be required for initiating the expression of Prox1, responsible for lymphatic commitment of venous ECs. Small animal models like zebrafish embryos and Xenopus laevis tadpoles have been very useful to elucidate mechanisms of (lymph) vascular development. Therefore, the role of NR2F2 in (lymph) vascular development was studied by eliminating its expression in these models. Like in mice, absence of NR2F2 in zebrafish resulted in distinct vascular defects including loss of venous marker expression, major trunk vessel fusion and vascular leakage. Both in zebrafish and Xenopus the development of the main lymphatic structures was severely hampered. NR2F2 knockdown significantly decreased prox1 expression in zebrafish ECs and the same manipulation affected lymphatic (L)EC commitment, migration and function in Xenopus tadpoles. Therefore, the role of NR2F2 in EC fate determination is evolutionary conserved.

  16. Ginsenoside Rg1 enhances lymphatic transport of intrapulmonary silica via VEGF-C/VEGFR-3 signaling in silicotic rats.

    PubMed

    Yu, Jie; Mao, Lijun; Guan, Li; Zhang, Yanlin; Zhao, Jinyuan

    2016-03-25

    Ginsenoside Rg1, extracted mainly from Panax ginseng, has been shown to exert strong pro-angiogenic activities in vivo. But it is unclear whether ginsenoside Rg1 could promote lung lymphangiogenesis to improve lymphatic transport of intrapulmonary silica in silicotic rats. Here we investigated the effect of ginsenoside Rg1 on lymphatic transport of silica during experimental silicosis, and found that ginsenoside Rg1 treatment significantly raised the silicon content in tracheobronchial lymph nodes and serum to reduce the silicon level in lung interstitium, meanwhile increased pulmonary lymphatic vessel density by enhancing the protein and mRNA expressions of vascular endothelial growth factor-C (VEGF-C) and vascular endothelial growth factor receptor-3 (VEGFR-3). The stimulative effect of ginsenoside Rg1 on lymphatic transport of silica was actively correlated with its pro-lymphangiogenic identity. And VEGFR-3 inhibitor SAR131675 blocked these above effects of ginsenoside Rg1. These findings suggest that ginsenoside Rg1 exhibits good protective effect against lung burden of silica during experimental silicosis through improving lymphatic transport of intrapulmonary silica, which is potentially associated with the activation of VEGF-C/VEGFR-3 signaling pathway.

  17. Personalized Therapy for Generalized Lymphatic Anomaly/Gorham-Stout Disease With a Combination of Sunitinib and Taxol.

    PubMed

    Rössler, Jochen; Saueressig, Ulrich; Kayser, Gian; von Winterfeld, Moritz; Klement, Gianoula L

    2015-11-01

    The recently revised ISSVA classification approved in Melbourne in April 2014 recognizes generalized lymphatic anomaly and lymphatic malformation in Gorham-Stout disease. The 2 entities can overlap in presentation, as both are characterized by destructive lymphatic vessel invasion of the axial skeleton and surrounding soft tissues. At least at present, no standard therapeutic options exist, and due to the rarity of the disease, no clinical trials are available. We present 2 patients, 1 with generalized lymphatic anomaly and 1 with lymphatic malformation in Gorham-Stout disease, with severe exacerbation during puberty. The first child presented in florid pulmonary failure and pleural effusion, the other with severe pain due to bone destruction of the pelvis and inability to walk. Both were treated using individualized protocols. The manuscript describes the rationale for choosing sunitinib in combination with low-dose (metronomic) taxol. Both patients experienced clinical and radiologic response without major toxicities, suggesting that patients with rare conditions may benefit from individualized, molecularly based therapies. PMID:26458155

  18. The mesenteric lymph duct cannulated rat model: application to the assessment of intestinal lymphatic drug transport.

    PubMed

    Trevaskis, Natalie L; Hu, Luojuan; Caliph, Suzanne M; Han, Sifei; Porter, Christopher J H

    2015-03-06

    The intestinal lymphatic system plays key roles in fluid transport, lipid absorption and immune function. Lymph flows directly from the small intestine via a series of lymphatic vessels and nodes that converge at the superior mesenteric lymph duct. Cannulation of the mesenteric lymph duct thus enables the collection of mesenteric lymph flowing from the intestine. Mesenteric lymph consists of a cellular fraction of immune cells (99% lymphocytes), aqueous fraction (fluid, peptides and proteins such as cytokines and gut hormones) and lipoprotein fraction (lipids, lipophilic molecules and apo-proteins). The mesenteric lymph duct cannulation model can therefore be used to measure the concentration and rate of transport of a range of factors from the intestine via the lymphatic system. Changes to these factors in response to different challenges (e.g., diets, antigens, drugs) and in disease (e.g., inflammatory bowel disease, HIV, diabetes) can also be determined. An area of expanding interest is the role of lymphatic transport in the absorption of orally administered lipophilic drugs and prodrugs that associate with intestinal lipid absorption pathways. Here we describe, in detail, a mesenteric lymph duct cannulated rat model which enables evaluation of the rate and extent of lipid and drug transport via the lymphatic system for several hours following intestinal delivery. The method is easily adaptable to the measurement of other parameters in lymph. We provide detailed descriptions of the difficulties that may be encountered when establishing this complex surgical method, as well as representative data from failed and successful experiments to provide instruction on how to confirm experimental success and interpret the data obtained.

  19. [Chylous reflux and chylous ascites in lymphatic dysplasia, with the lymphographic demonstration of mediastinal and retroperitoneal lymphatic cysts].

    PubMed

    Hermanutz, K D; Boldt, I; Frotscher, U

    1975-01-01

    Two patients with congenital dysplasia of the lymphatic system and with chylous ascites are described. In one 24-year old woman with this rare condition, it was possible to demonstrate for the first time numerous mediastinal lymphatic cysts during lymphangiography. Both patients showed an abnormality of the retroperitoneal lymphatics, consisting of lymphatic dilatation and cysts. In the investigation of chylous ascites, direct lymphangiography must be regarded as a valuable and necessary investigation.

  20. Variations in lung lymphatic drainage into the inferior tracheobronchial lymph nodes junction: Applications in lung cancer.

    PubMed

    Ndiaye, Assane; Dimarino, Vincent; Ndiaye, Aïnina; Gaye, Magaye; Ba, Papa Salmane; Nazarian, Serge

    2016-10-01

    The group of inferior tracheobronchial lymph nodes (ITB) is a lymphatic junction through which the lymph from both lungs is carried. Lymphatic activity in this area can be used to assess the lymphatic spreading of lung cancers. Our aim was to quantify lymph drainage from the lung segments towards the ITB group and to determine the direction of the lymph flow into other mediastinal and abdominal lymph nodes. We injected dye directly into the subpleural lymphatic vessels in 100 lung segments of 25 fresh cadaver subjects; the cadavers were then dissected. Thirty-eight segments (38%) drained into the ITB group in 18 subjects. The drainage into the ITB group involved 15.6% of the upper lobe segments, 87.5% of the middle lobe segments, and 70.6% of the lower lobe segments in the right lung. On the left, 6.9% of the upper lobe segments and 83.3% of the lower lobe segments were drained into the ITB group. For three subjects, the dye did not pass beyond the ITB group. The efferent vessels of the ITB group drained towards the right paratracheal and tracheoesophageal chains in 12 subjects and through the left ascending recurrent chain in five subjects. For six subjects, the efferent channels reached the abdominal lymph nodes. A contralateral drainage involved 14 segments (36%). The size and variety of the segments that drain into the ITB group, coupled with the efferent contralateral mediastinal and abdominal pathways, account for the severity of metastasis to this area. Clin. Anat. 29:955-962, 2016. © 2016 Wiley Periodicals, Inc. PMID:27480071

  1. Lymphatic Leak Complicating Central Venous Catheter Insertion

    SciTech Connect

    Barnacle, Alex M. Kleidon, Tricia M.

    2005-12-15

    Many of the risks associated with central venous access are well recognized. We report a case of inadvertent lymphatic disruption during the insertion of a tunneled central venous catheter in a patient with raised left and right atrial pressures and severe pulmonary hypertension, which led to significant hemodynamic instability. To our knowledge, this rare complication is previously unreported.

  2. Effector T cell egress via afferent lymph modulates local tissue inflammation1

    PubMed Central

    Gómez, Daniela; Diehl, Malissa C.; Crosby, Erika J.; Weinkopff, Tiffany; Debes, Gudrun F.

    2015-01-01

    Memory/effector T cells recirculate through extralymphoid tissues by entering from blood and egressing via afferent lymph. While T cell entry into effector sites is key to inflammation, the relevance of T cell egress to this process is unknown. Here we found that antigen recognition at the effector site reduced the tissue egress of pro-inflammatory Th1 cells in a mouse model of delayed hypersensitivity. Transgenic expression of ‘tissue exit receptor’ CCR7 enhanced lymphatic egress of antigen-sequestered Th1 cells from the inflamed site and ameliorated inflammation. In contrast, lack of CCR7 on Th1 cells diminished their tissue egress while enhancing inflammation. Lymph-borne Th1 and Th17 cells draining the inflamed skin of sheep migrated toward the CCR7 ligand CCL21, suggesting the CCR7-CCL21 axis as a physiological target in regulating inflammation. In conclusion, exit receptors can be targeted to modulate T cell dwell time and inflammation at effector sites, revealing T cell tissue egress as a novel control point of inflammation. PMID:26355150

  3. Differential central projections of vestibular afferents in pigeons

    NASA Technical Reports Server (NTRS)

    Dickman, J. D.; Fang, Q.

    1996-01-01

    The question of whether a differential distribution of vestibular afferent information to central nuclear neurons is present in pigeons was studied using neural tracer compounds. Discrete tracing of afferent fibers innervating the individual semicircular canal and otolith organs was produced by sectioning individual branches of the vestibular nerve that innervate the different receptor organs and applying crystals of horseradish peroxidase, or a horseradish peroxidase/cholera toxin mixture, or a biocytin compound for neuronal uptake and transport. Afferent fibers and their terminal distributions within the brainstem and cerebellum were visualized subsequently. Discrete areas in the pigeon central nervous system that receive primary vestibular input include the superior, dorsal lateral, ventral lateral, medial, descending, and tangential vestibular nuclei; the A and B groups; the intermediate, medial, and lateral cerebellar nuclei; and the nodulus, the uvula, and the paraflocculus. Generally, the vertical canal afferents projected heavily to medial regions in the superior and descending vestibular nuclei as well as the A group. Vertical canal projections to the medial and lateral vestibular nuclei were observed but were less prominent. Horizontal canal projections to the superior and descending vestibular nuclei were much more centrally located than those of the vertical canals. A more substantial projection to the medial and lateral vestibular nuclei was seen with horizontal canal afferents compared to vertical canal fibers. Afferents innervating the utricle and saccule terminated generally in the lateral regions of all vestibular nuclei in areas that were separate from the projections of the semicircular canals. In addition, utricular fibers projected to regions in the vestibular nuclei that overlapped with the horizontal semicircular canal terminal fields, whereas saccular afferents projected to regions that received vertical canal fiber terminations. Lagenar

  4. Afferent innervation of the utricular macula in pigeons

    NASA Technical Reports Server (NTRS)

    Si, Xiaohong; Zakir, Mridha Md; Dickman, J. David

    2003-01-01

    Biotinylated dextran amine (BDA) was used to retrogradely label afferents innervating the utricular macula in adult pigeons. The pigeon utriclar macula consists of a large rectangular-shaped neuroepithelium with a dorsally curved anterior edge and an extended medioposterior tail. The macula could be demarcated into several regions based on cytoarchitectural differences. The striola occupied 30% of the macula and contained a large density of type I hair cells with fewer type II hair cells. Medial and lateral extrastriola zones were located outside the striola and contained only type II hair cells. A six- to eight-cell-wide band of type II hair cells existed near the center of the striola. The reversal line marked by the morphological polarization of hair cells coursed throughout the epithelium, near the peripheral margin, and through the center of the type II band. Calyx afferents innervated type I hair cells with calyceal terminals that contained between 2 and 15 receptor cells. Calyx afferents were located only in the striola region, exclusive of the type II band, had small total fiber innervation areas and low innervation densities. Dimorph afferents innervated both type I and type II hair cells with calyceal and bouton terminals and were primarily located in the striola region. Dimorph afferents had smaller calyceal terminals with few type I hair cells, extended fiber branches with bouton terminals and larger innervation areas. Bouton afferents innervated only type II hair cells in the extrastriola and type II band regions. Bouton afferents innervating the type II band had smaller terminal fields with fewer bouton terminals and smaller innervation areas than fibers located in the extrastriolar zones. Bouton afferents had the most bouton terminals on the longest fibers, the largest innervation areas with the highest innervation densities of all afferents. Among all afferents, smaller terminal innervation fields were observed in the striola and large fields were

  5. b-FGF Induces Corneal Blood and Lymphatic Growth in a Spatially Distinct Pattern

    PubMed Central

    Hajrasouliha, Amir R.; Sadrai, Zahra; Chauhan, Sunil K.; Dana, Reza

    2013-01-01

    Purpose To study the spatial variances in ligand expression and angiogenic effect in response to the inflammatory response induced by b-FGF. Methods b-FGF micropellets (80ng) were implanted in the temporal side of the cornea of Balbc/c mice. On days 1, 3, and 7 blood (heme) and lymph-angiogenesis were observed by immunofluorescence staining of corneal flat mounts with LYVE-1 and CD31 to identify lymphatic and blood vessels, respectively. A second group of corneas were harvested for quantitative RT-PCR. Each cornea was divided in two different area defines as (i) pre-pellet area and (ii) opposite-pellet area. Expression of VEGF ligands were evaluated using Real-time PCR in each respective zone. Results Blood vessels grew into the cornea from the pre-pellet area while corneal lymphatic vessels grew from the opposite-pellet area toward the center of the cornea. VEGF-A was upregulated in the pre-pellet while VEGF-D expression was mostly observed in the opposite-pellet area. VEGF-C level increased simultaneously in both areas. Conclusion A single inducing factor, i.e., b-FGF, may simultaneously provoke heme-and lymph-angiogenesis in different locations of the cornea through differential expression of VEGF ligands. This distinctive spatial pattern should be considered while evaluating the corneal predilection for inflammation beyond that which is directly visible by slit lamp examination. PMID:22467003

  6. Nature's rheologists: Lymphatic endothelial cells control migration in response to shear stress

    NASA Astrophysics Data System (ADS)

    Fuller, Gerald; Dunn, Alex; Surya, Vinay

    2015-03-01

    Endothelial cells (ECs) line the inner surface of blood and lymphatic vessels and are sensitive to fluid flow as part of their physiological function. EC organization, migration and vessel development are profoundly influenced by shear stresses, with important implications in cardiovascular disease and tumor metastasis. How ECs sense fluid flow is a central and unanswered question in cardiovascular biology. We developed a high-throughput live-cell flow chamber that models the gradients in wall shear stress experienced by ECs in vivo. Live-cell imaging allows us to probe cellular responses to flow, most notably EC migration, which has a key role in vessel remodeling. We find that most EC subtypes, including ECs from the venous, arterial, and microvascular systems, migrate in the flow direction. In contrast, human lymphatic microvascular ECs (hLMVECs) migrate against flow and up spatial gradients in wall shear stress. Further experiments reveal that hLMVECs are sensitive to the magnitude, direction, and the local spatial gradients in wall shear stress. Lastly, recent efforts have aimed to link this directional migration to spatial gradients in cell-mediated small molecule emission that may be linked to the gradient in wall shear stress.

  7. Lymphatic spreading and lymphadenectomy for esophageal carcinoma

    PubMed Central

    Ji, Xiang; Cai, Jie; Chen, Yao; Chen, Long-Qi

    2016-01-01

    Esophageal carcinoma (EC) is a highly lethal malignancy with a poor prognosis. One of the most important prognostic factors in EC is lymph node status. Therefore, lymphadenectomy has been recognized as a key that influences the outcome of surgical treatment for EC. However, the lymphatic drainage system of the esophagus, including an abundant lymph-capillary network in the lamina propria and muscularis mucosa, is very complex with cervical, mediastinal and celiac node spreading. The extent of lymphadenectomy for EC has always been controversial because of the very complex pattern of lymph node spreading. In this article, published literature regarding lymphatic spreading was reviewed and the current lymphadenectomy trends for EC are discussed. PMID:26843917

  8. Breast cancer cells condition lymphatic endothelial cells within pre-metastatic niches to promote metastasis

    PubMed Central

    Lee, Esak; Fertig, Elana J.; Jin, Kideok; Sukumar, Saraswati; Pandey, Niranjan B.; Popel, Aleksander S.

    2014-01-01

    Breast cancer metastasis involves lymphatic dissemination in addition to hematogenous spreading. Although stromal lymphatic vessels (LVs) serve as initial metastatic routes, roles of organ-residing LVs are under-investigated. Here we show that lymphatic endothelial cells (LECs), a component of LVs within pre-metastatic niches, are conditioned by triple-negative breast cancer (TNBC) cells to accelerate metastasis. LECs within the lungs and lymph nodes, conditioned by tumor-secreted factors express CCL5 that is not expressed either in normal LECs or cancer cells, and direct tumor dissemination into these tissues. Moreover, tumor-conditioned LECs promote angiogenesis in these organs, allowing tumor extravasation and colonization. Mechanistically, tumor cell-secreted IL6 causes Stat3 phosphorylation in LECs. This pStat3 induces HIF-1α and VEGF, and a pStat3-pc-Jun-pATF-2 ternary complex induces CCL5 expression in LECs. This study demonstrates anti-metastatic activities of multiple repurposed drugs, blocking a self-reinforcing paracrine loop between breast cancer cells and LECs. PMID:25178650

  9. Low-cost microcontroller platform for studying lymphatic biomechanics in vitro

    PubMed Central

    Kornuta, Jeffrey A.; Nipper, Matthew E.; Dixon, J. Brandon

    2012-01-01

    The pumping innate to collecting lymphatic vessels routinely exposes the endothelium to oscillatory wall shear stress and other dynamic forces. However, studying the mechanical sensitivity of the lymphatic endothelium remains a difficult task due to limitations of commercial or custom systems to apply a variety of time-varying stresses in vitro. Current biomechanical in vitro testing devices are very expensive, limited in capability, or highly complex; rendering them largely inaccessible to the endothelial cell biology community. To address these short-comings, the authors propose a reliable, low-cost platform for augmenting the capabilities of commercially available pumps to produce a wide variety of flow rate waveforms. In particular, the Arduino Uno, a microcontroller development board, is used to provide open-loop control of a digital peristaltic pump using precisely-timed serial commands. In addition, the flexibility of this platform is further demonstrated through its support of a custom-built cell-straining device capable of producing oscillatory strains with varying amplitudes and frequencies. Hence, this microcontroller development board is shown to be an inexpensive, precise, and easy-to-use tool for supplementing in vitro assays to quantify the effects of biomechanical forces on lymphatic endothelial cells. PMID:23178036

  10. Low-cost microcontroller platform for studying lymphatic biomechanics in vitro.

    PubMed

    Kornuta, Jeffrey A; Nipper, Matthew E; Dixon, J Brandon

    2013-01-01

    The pumping innate to collecting lymphatic vessels routinely exposes the endothelium to oscillatory wall shear stress and other dynamic forces. However, studying the mechanical sensitivity of the lymphatic endothelium remains a difficult task due to limitations of commercial or custom systems to apply a variety of time-varying stresses in vitro. Current biomechanical in vitro testing devices are very expensive, limited in capability, or highly complex; rendering them largely inaccessible to the endothelial cell biology community. To address these shortcomings, the authors propose a reliable, low-cost platform for augmenting the capabilities of commercially available pumps to produce a wide variety of flow rate waveforms. In particular, the Arduino Uno, a microcontroller development board, is used to provide open-loop control of a digital peristaltic pump using precisely timed serial commands. In addition, the flexibility of this platform is further demonstrated through its support of a custom-built cell-straining device capable of producing oscillatory strains with varying amplitudes and frequencies. Hence, this microcontroller development board is shown to be an inexpensive, precise, and easy-to-use tool for supplementing in vitro assays to quantify the effects of biomechanical forces on lymphatic endothelial cells.

  11. Effects of hypoxia on vertebrate blood vessels.

    PubMed

    Russell, Michael J; Dombkowski, Ryan A; Olson, Kenneth R

    2008-03-01

    Hypoxia contracts mammalian respiratory vessels and increases vascular resistance in respiratory tissues of many vertebrates. In systemic vessels these responses vary, hypoxia relaxes mammalian vessels and contracts systemic arteries from cyclostomes. It has been proposed that hypoxic vasoconstriction in cyclostome systemic arteries is the antecedent to mammalian hypoxic pulmonary vasoconstriction, however, phylogenetic characterization of hypoxic responses is lacking. In this study, we characterized the hypoxic response of isolated systemic and respiratory vessels from a variety of vertebrates using standard myography. Pre-gill/respiratory (ventral aorta, afferent branchial artery, pulmonary artery) and post-gill/systemic (dorsal and thoracic aortas, efferent branchial artery) from lamprey (Petromyzon marinus), sandbar shark (Carcharhinus plumbeus), yellowfin tuna (Thunnus albacares), American bullfrog (Rana catesbeiana), American alligator (Alligator mississippiensis), Pekin duck (Anas platyrhynchos domesticus), chicken (Gallus domesticus) and rat (Rattus norvegicus) were exposed to hypoxia at rest or during pre-stimulation (elevated extracellular potassium, epinephrine or norepinephrine). Hypoxia produced a relaxation or transient contraction followed by relaxation in all pre-gill vessels, except for contraction in lamprey, and vasoconstriction or tri-phasic constriction-dilation-constriction in all pulmonary vessels. Hypoxia contracted systemic vessels from all animals except shark and rat and in pre-contracted rat aortas it produced a transient contraction followed by relaxation. These results show that while the classic "systemic hypoxic vasodilation and pulmonary hypoxic vasoconstriction" may occur in the microcirculation, the hypoxic response of the vertebrate macrocirculation is quite variable. These findings also suggest that hypoxic vasoconstriction is a phylogenetically ancient response. PMID:18214862

  12. Histaminergic afferent system in the cerebellum: structure and function.

    PubMed

    Li, Bin; Zhu, Jing-Ning; Wang, Jian-Jun

    2014-01-01

    Histaminergic afferent system of the cerebellum, having been considered as an essential component of the direct hypothalamocerebellar circuits, originates from the tuberomammillary nucleus in the hypothalamus. Unlike the mossy fibers and climbing fibers, the histaminergic afferent fibers, a third type of cerebellar afferents, extend fine varicose fibers throughout the cerebellar cortex and nuclei. Histamine receptors, belonging to the family of G protein-coupled receptors, are widely present in the cerebellum. Through these histamine receptors, histamine directly excites Purkinje cells and granule cells in the cerebellar cortex, as well as the cerebellar nuclear neurons. Therefore, the histaminergic afferents parallelly modulate these dominant components in the cerebellar circuitry and consequently influence the final output of the cerebellum. In this way, the histaminergic afferent system actively participates in the cerebellum-mediated motor balance and coordination and nonsomatic functions. Accordingly, histaminergic reagents may become potential drugs for clinical treatment of cerebellar ataxia and other cerebellar disease. On the other hand, considering the hypothalamus is a high regulatory center for autonomic and visceral activities, the hypothalamocerebellar histaminergic fibers/projections, bridging the nonsomatic center to somatic structure, may play a critical role in the somatic-nonsomatic integration.

  13. Thermal nociceptive properties of trigeminal afferent neurons in rats

    PubMed Central

    2010-01-01

    Background Although nociceptive afferents innervating the body have been heavily studied form many years, much less attention has been paid to trigeminal afferent biology. In particular, very little is known concerning trigeminal nociceptor responses to heat, and almost nothing in the rat. This study uses a highly controlled and reproducible diode laser stimulator to investigate the activation of trigeminal afferents to noxious skin heating. Results The results of this experiment demonstrate that trigeminal thermonociceptors are distinct from themonociceptors innervating the limbs. Trigeminal nociceptors have considerably slower action potential conduction velocities and lower temperature thresholds than somatic afferent neurons. On the other hand, nociceptors innervating both tissue areas separate into those that respond to short pulse, high rate skin heating and those that respond to long pulse, low rate skin heating. Conclusions This paper provides the first description in the literature of the in vivo properties of thermonociceptors in rats. These finding of two separate populations aligns with the separation between C and A-delta thermonociceptors innervating the paw, but have significant differences in terms of temperature threshold and average conduction velocities. An understanding of the temperature response properties of afferent neurons innervating the paw skin have been critical in many mechanistic discoveries, some leading to new pain therapies. A clear understanding of trigeminal nociceptors may be similarly useful in the investigation of trigeminal pain mechanisms and potential therapies. PMID:20609212

  14. Gut vagal afferents differentially modulate innate anxiety and learned fear.

    PubMed

    Klarer, Melanie; Arnold, Myrtha; Günther, Lydia; Winter, Christine; Langhans, Wolfgang; Meyer, Urs

    2014-05-21

    Vagal afferents are an important neuronal component of the gut-brain axis allowing bottom-up information flow from the viscera to the CNS. In addition to its role in ingestive behavior, vagal afferent signaling has been implicated modulating mood and affect, including distinct forms of anxiety and fear. Here, we used a rat model of subdiaphragmatic vagal deafferentation (SDA), the most complete and selective vagal deafferentation method existing to date, to study the consequences of complete disconnection of abdominal vagal afferents on innate anxiety, conditioned fear, and neurochemical parameters in the limbic system. We found that compared with Sham controls, SDA rats consistently displayed reduced innate anxiety-like behavior in three procedures commonly used in preclinical rodent models of anxiety, namely the elevated plus maze test, open field test, and food neophobia test. On the other hand, SDA rats exhibited increased expression of auditory-cued fear conditioning, which specifically emerged as attenuated extinction of conditioned fear during the tone re-exposure test. The behavioral manifestations in SDA rats were associated with region-dependent changes in noradrenaline and GABA levels in key areas of the limbic system, but not with functional alterations in the hypothalamus-pituitary-adrenal grand stress. Our study demonstrates that innate anxiety and learned fear are both subjected to visceral modulation through abdominal vagal afferents, possibly via changing limbic neurotransmitter systems. These data add further weight to theories emphasizing an important role of afferent visceral signals in the regulation of emotional behavior.

  15. In vitro Functional Characterization of Mouse Colorectal Afferent Endings

    PubMed Central

    Feng, Bin; Gebhart, G.F.

    2015-01-01

    This video demonstrates in detail an in vitro single-fiber electrophysiological recording protocol using a mouse colorectum-nerve preparation. The approach allows unbiased identification and functional characterization of individual colorectal afferents. Extracellular recordings of propagated action potentials (APs) that originate from one or a few afferent (i.e., single-fiber) receptive fields (RFs) in the colorectum are made from teased nerve fiber fascicles. The colorectum is removed with either the pelvic (PN) or lumbar splanchnic (LSN) nerve attached and opened longitudinally. The tissue is placed in a recording chamber, pinned flat and perfused with oxygenated Krebs solution. Focal electrical stimulation is used to locate the colorectal afferent endings, which are further tested by three distinct mechanical stimuli (blunt probing, mucosal stroking and circumferential stretch) to functionally categorize the afferents into five mechanosensitive classes. Endings responding to none of these mechanical stimuli are categorized as mechanically-insensitive afferents (MIAs). Both mechanosensitive and MIAs can be assessed for sensitization (i.e., enhanced response, reduced threshold, and/or acquisition of mechanosensitivity) by localized exposure of RFs to chemicals (e.g., inflammatory soup (IS), capsaicin, adenosine triphosphate (ATP)). We describe the equipment and colorectum–nerve recording preparation, harvest of colorectum with attached PN or LSN, identification of RFs in the colorectum, single-fiber recording from nerve fascicles, and localized application of chemicals to the RF. In addition, challenges of the preparation and application of standardized mechanical stimulation are also discussed. PMID:25651300

  16. Semicircular Canal Geometry, Afferent Sensitivity And Animal Behavior

    PubMed Central

    Hullar, Timothy A.

    2008-01-01

    The geometry of the semicircular canals has been used in evolutionary studies to predict the behaviors of extinct animals. These predictions have relied on an assumption that the responses of the canals can be determined from their dimensions, and that an organism’s behavior can be determined from these responses. However, the relationship between a canal’s sensitivity and its size is not well known. An intraspecies comparison among canal responses in each of three species (cat, squirrel monkey, and pigeon) was undertaken to evaluate various models of canal function and determine how their dimensions may be related to afferent physiology. All models predicted the responses of the cat afferents, but the models performed less well for squirrel monkey and pigeon. Possible causes for this discrepancy include incorrectly assuming that afferent responses accurately represent canal function, or errors in current biophysical models of the canals. These findings leave open the question as to how reliably canal anatomy can be used to estimate afferent responses and how closely afferent responses are related to behavior. Other labyrinthine features—such as orientation of the horizontal canal, which is reliably held near earth-horizontal across many species—may be better to use when extrapolating the posture and related behavior of extinct animals from labyrinthine morphology. PMID:16550591

  17. Emerging trends in the pathophysiology of lymphatic contractile function.

    PubMed

    Chakraborty, Sanjukta; Davis, Michael J; Muthuchamy, Mariappan

    2015-02-01

    Lymphatic contractile dysfunction is central to a number of pathologies that affect millions of people worldwide. Due to its critical role in the process of inflammation, a dysfunctional lymphatic system also compromises the immune response, further exacerbating a number of inflammation related diseases. Despite the critical physiological functions accomplished by the transport of lymph, a complete understanding of the contractile machinery of the lymphatic system lags far behind that of the blood vasculature. However, there has been a surge of recent research focusing on different mechanisms that underlie both physiological and pathophysiological aspects of lymphatic contractile function. This review summarizes those emerging paradigms that shed some novel insights into the contractile physiology of the lymphatics in normal as well as different disease states. In addition, this review emphasizes the recent progress made in our understanding of various contractile parameters and regulatory elements that contribute to the normal functioning of the lymphatics.

  18. Lymphatic imaging: Lymphography, computed tomography and scintigraphy, 2nd ed

    SciTech Connect

    Close, M.E.; Wallace, S.

    1985-01-01

    The latest addition to the Golden's Diagnostic Radiology series deals not only with imaging of the lymphatic system but also with lymphatic anatomy, its pathophysiology, and treatment of disorders. The first two chapters deal with the history of the discovery of the lymphatic system and its normal anatomy. The section on technique contains practical information and discussion of lymphatic physiology and the pathology of lymphomas. Half of the book's 16 chapters are devoted to problems encountered in clinical imaging. The approach is both by anatomy (thorax, neck, abdomen) and pathology (benign disease, lymphoma, solid tumors).

  19. Adipose afferent reflex: sympathetic activation and obesity hypertension.

    PubMed

    Xiong, X-Q; Chen, W-W; Zhu, G-Q

    2014-03-01

    Excessive sympathetic activity contributes to the pathogenesis of hypertension and the progression of the related organ damage. Adipose afferent reflex (AAR) is a sympatho-excitatory reflex that the afferent activity from white adipose tissue (WAT) increases sympathetic outflow and blood pressure. Hypothalamic paraventricular nucleus (PVN or PVH) is one of the central sites in the control of the AAR, and ionotropic glutamate receptors in the nucleus mediate the AAR. The AAR is enhanced in obesity and obesity hypertension. Enhanced WAT afferent activity and AAR contribute to the excessive sympathetic activation and hypertension in obesity. Blockage of the AAR attenuates the excessive sympathetic activity and hypertension. Leptin may be one of sensors in the WAT for the AAR, and is involved in the enhanced AAR in obesity and hypertension. This review focuses on the neuroanatomical basis and physiological functions of the AAR, and the important role of the enhanced AAR in the pathogenesis of obesity hypertension.

  20. A novel role for TRPM8 in visceral afferent function.

    PubMed

    Harrington, Andrea M; Hughes, Patrick A; Martin, Christopher M; Yang, Jing; Castro, Joel; Isaacs, Nicole J; Blackshaw, L Ashley; Brierley, Stuart M

    2011-07-01

    Transient receptor potential ion channel melastatin subtype 8 (TRPM8) is activated by cold temperatures and cooling agents, such as menthol and icilin. Compounds containing peppermint are reported to reduce symptoms of bowel hypersensitivity; however, the underlying mechanisms of action are unclear. Here we determined the role of TRPM8 in colonic sensory pathways. Laser capture microdissection, quantitative reverse transcription-polymerase chain reaction (RT-PCR), immunofluorescence, and retrograde tracing were used to localise TRPM8 to colonic primary afferent neurons. In vitro extracellular single-fibre afferent recordings were used to determine the effect of TRPM8 channel activation on the chemosensory and mechanosensory function of colonic high-threshold afferent fibres. TRPM8 mRNA was present in colonic DRG neurons, whereas TRPM8 protein was present on nerve fibres throughout the wall of the colon. A subpopulation (24%, n=58) of splanchnic serosal and mesenteric afferents tested responded directly to icilin (5 μmol/L). Subsequently, icilin significantly desensitised afferents to mechanical stimulation (P<.0001; n=37). Of the splanchnic afferents responding to icilin, 21 (33%) also responded directly to the TRPV1 agonist capsaicin (3 μmol/L), and icilin reduced the direct chemosensory response to capsaicin. Icilin also prevented mechanosensory desensitization and sensitization induced by capsaicin and the TRPA1 agonist AITC (40 μmol/L), respectively. TRPM8 is present on a select population of colonic high threshold sensory neurons, which may also co-express TRPV1. TRPM8 couples to TRPV1 and TRPA1 to inhibit their downstream chemosensory and mechanosensory actions. PMID:21489690

  1. Determinants of Spatial and Temporal Coding by Semicircular Canal Afferents

    PubMed Central

    Highstein, Stephen M.; Rabbitt, Richard D.; Holstein, Gay R.; Boyle, Richard D.

    2010-01-01

    The vestibular semicircular canals are internal sensors that signal the magnitude, direction, and temporal properties of angular head motion. Fluid mechanics within the 3-canal labyrinth code the direction of movement and integrate angular acceleration stimuli over time. Directional coding is accomplished by decomposition of complex angular accelerations into 3 biomechanical components—one component exciting each of the 3 ampullary organs and associated afferent nerve bundles separately. For low-frequency angular motion stimuli, fluid displacement within each canal is proportional to angular acceleration. At higher frequencies, above the lower corner frequency, real-time integration is accomplished by viscous forces arising from the movement of fluid within the slender lumen of each canal. This results in angular velocity sensitive fluid displacements. Reflecting this, a subset of afferent fibers indeed report angular acceleration to the brain for low frequencies of head movement and report angular velocity for higher frequencies. However, a substantial number of afferent fibers also report angular acceleration, or a signal between acceleration and velocity, even at frequencies where the endolymph displacement is known to follow angular head velocity. These non-velocity-sensitive afferent signals cannot be attributed to canal biomechanics alone. The responses of non-velocity-sensitive cells include a mathematical differentiation (first-order or fractional) imparted by hair-cell and/or afferent complexes. This mathematical differentiation from velocity to acceleration cannot be attributed to hair cell ionic currents, but occurs as a result of the dynamics of synaptic transmission between hair cells and their primary afferent fibers. The evidence for this conclusion is reviewed below. PMID:15845995

  2. Impaired humoral immunity and tolerance in K14-VEGFR-3-Ig mice that lack dermal lymphatic drainage

    PubMed Central

    Thomas, Susan N.; Rutkowski, Joseph M.; Pasquier, Miriella; Kuan, Emma L.; Alitalo, Kari; Randolph, Gwendalyn J.; Swartz, Melody A.

    2012-01-01

    Lymphatic vessels transport interstitial fluid, soluble antigen, and immune cells from peripheral tissues to lymph nodes (LNs), yet the contribution of peripheral lymphatic drainage to adaptive immunity remains poorly understood. We examined immune responses to dermal vaccination and contact hypersensitivity (CHS) challenge in K14-VEGFR-3-Ig mice, which lack dermal lymphatic capillaries and experience markedly depressed transport of solutes and dendritic cells from the skin to draining LNs. In response to dermal immunization, K14-VEGFR-3-Ig mice produced lower antibody titers. In contrast, although delayed, T cell responses were robust after 21 days, including high levels of antigen-specific CD8+ T cells and production of IFN-γ, IL-4 and IL-10 upon restimulation. T cell-mediated CHS responses were strong in K14-VEGFR-3-Ig mice, but importantly, their ability to induce CHS tolerance in the skin was impaired. Additionally, one-year-old mice displayed multiple signs of autoimmunity. These data suggest that lymphatic drainage plays more important roles in regulating humoral immunity and peripheral tolerance than in effector T cell immunity. PMID:22844119

  3. Du-Huo-Ji-Sheng-Tang Attenuates Inflammation of TNF-Tg Mice Related to Promoting Lymphatic Drainage Function

    PubMed Central

    Chen, Yan; Li, Jinlong; Li, Qiang; Wang, Tengteng; Xing, Lianping; Xu, Hao; Wang, Yongjun; Shi, Qi; Zhou, Quan; Liang, Qianqian

    2016-01-01

    To investigate whether Du-Huo-Ji-Sheng-Tang (DHJST) attenuate inflammation of RA related to lymphatic drainage function in vivo, we treated eight 3-month-old TNF-Tg mice with DHJST (12 g/kg) or the same volume of physiological saline once every day for 12 weeks, and 3-month-old WT littermates were used as negative control. After twelve weeks, we performed NIR-ICG imaging and found that DHJST increased the ICG clearance at the footpad and the pulse of efferent lymphatic vessel between popliteal lymph node and footpad. Histology staining at ankle joints showed that DHJST decreases synovial inflammation, bone erosion, cartilage erosion, and TRAP+ osteoclast area in TNF-Tg mice. Immunohistochemical staining by using anti-Lyve-1 and anti-podoplanin antibody showed that DHJST stimulated lymphangiogenesis in ankle joints of TNF-Tg mice. And zebrafish study suggested that DHJST promoted the formation of lymphatic thoracic duct. In conclusion, DHJST inhibits inflammation severity and promotes lymphangiogenesis and lymphatic drainage function of TNF-Tg mice. PMID:27239212

  4. The afferent pupillary defect in acute optic neuritis.

    PubMed Central

    Ellis, C J

    1979-01-01

    Twenty-two patients with acute optic neuritis were studied by the techniques of infrared pupillometry and visual evoked responses (VER) to pattern reversal. A relative afferent pupillary defect was found in all cases and the magnitude of this defect was found to be related to the amplitude, but not to the latency, of the VER. During follow-up the afferent defect was found to remain persistently abnormal while other methods of clinical evaluation could not demonstrate abnormality reliably. The amplitude of the VER also remained low. PMID:501365

  5. Pre- and postjunctional alpha-adrenoceptors at sympathetic neuroeffector junction in bovine mesenteric lymphatics

    SciTech Connect

    Ohhashi, T.; Azuma, T.

    1986-01-01

    We studied isolated bovine mesenteric lymphatics to elucidate the pharmacological characteristics of pre- and postjunctional alpha-adrenoceptors at the sympathetic neuroeffector junction. Cylindrical strips were incubated with (/sup 3/H)-noradrenaline and mounted for superfusion. Electrical stimulation (2 Hz, 0.5 msec, 50 V) augmented the fractional release of labeled noradrenaline. Exogenous noradrenaline and clonidine caused a depression of the evoked tracer release. Phenoxybenzamine and yohimbine markedly enhanced the evoked overflow of adrenergic transmitter. Rings of lymphatic vessels were mounted for isometric tension recording in organ chambers filled with Krebs-Ringer bicarbonate solution. The vessels contracted when exposed to phenylephrine and clonidine. The ED50 of clonidine was significantly lower than that of phenylephrine. Prazosin caused a parallel shift to the right of the dose-response curve to phenylephrine. The antagonist, however, suppressed the magnitude of the maximum response to clonidine. Yohimbine caused parallel shift to the right of the dose-response curves to phenylephrine and clonidine, respectively. The Schild plots for yohimbine demonstrated that the drug was a competitive antagonist to phenylephrine and clonidine. The pA2 value of yohimbine to clonidine (7.6 +/- 0.4) was larger than that to phenylephrine (6.2 +/- 0.4). The pA2 value of prazosin to phenylephrine was 7.2 +/- 0.3. These results suggest that prejunctional alpha-adrenoceptors are involved in the negative feedback mechanism for autoregulation of noradrenaline release during postganglionic sympathetic nerve stimulation, and that both alpha 1- and alpha 2-like adrenoceptors do exist on lymphatic smooth muscle cells.

  6. Determining the combined effect of the lymphatic valve leaflets and sinus on resistance to forward flow.

    PubMed

    Wilson, John T; van Loon, Raoul; Wang, Wei; Zawieja, David C; Moore, James E

    2015-10-15

    The lymphatic system is vital to a proper maintenance of fluid and solute homeostasis. Collecting lymphatics are composed of actively contracting tubular vessels segmented by bulbous sinus regions that encapsulate bi-leaflet check valves. Valve resistance to forward flow strongly influences pumping performance. However, because of the sub-millimeter size of the vessels with flow rates typically <1 ml/h and pressures of a few cmH2O, resistance is difficult to measure experimentally. Using a newly defined idealized geometry, we employed an uncoupled approach where the solid leaflet deflections of the open valve were computed and lymph flow calculations were subsequently performed. We sought to understand: 1) the effect of sinus and leaflet size on the resulting deflections experienced by the valve leaflets and 2) the effects on valve resistance to forward flow of the fully open valve. For geometries with sinus-to-root diameter ratios >1.39, the average resistance to forward flow was 0.95×10(6)[g/(cm4 s)]. Compared to the viscous pressure drop that would occur in a straight tube the same diameter as the upstream lymphangion, valve leaflets alone increase the pressure drop up to 35%. However, the presence of the sinus reduces viscous losses, with the net effect that when combined with leaflets the overall resistance is less than that of the equivalent continuing straight tube. Accurately quantifying resistance to forward flow will add to the knowledge used to develop therapeutics for treating lymphatic disorders and may eventually lead to understanding some forms of primary lymphedema. PMID:26315921

  7. Determining the combined effect of the lymphatic valve leaflets and sinus on resistance to forward flow.

    PubMed

    Wilson, John T; van Loon, Raoul; Wang, Wei; Zawieja, David C; Moore, James E

    2015-10-15

    The lymphatic system is vital to a proper maintenance of fluid and solute homeostasis. Collecting lymphatics are composed of actively contracting tubular vessels segmented by bulbous sinus regions that encapsulate bi-leaflet check valves. Valve resistance to forward flow strongly influences pumping performance. However, because of the sub-millimeter size of the vessels with flow rates typically <1 ml/h and pressures of a few cmH2O, resistance is difficult to measure experimentally. Using a newly defined idealized geometry, we employed an uncoupled approach where the solid leaflet deflections of the open valve were computed and lymph flow calculations were subsequently performed. We sought to understand: 1) the effect of sinus and leaflet size on the resulting deflections experienced by the valve leaflets and 2) the effects on valve resistance to forward flow of the fully open valve. For geometries with sinus-to-root diameter ratios >1.39, the average resistance to forward flow was 0.95×10(6)[g/(cm4 s)]. Compared to the viscous pressure drop that would occur in a straight tube the same diameter as the upstream lymphangion, valve leaflets alone increase the pressure drop up to 35%. However, the presence of the sinus reduces viscous losses, with the net effect that when combined with leaflets the overall resistance is less than that of the equivalent continuing straight tube. Accurately quantifying resistance to forward flow will add to the knowledge used to develop therapeutics for treating lymphatic disorders and may eventually lead to understanding some forms of primary lymphedema.

  8. Co-ordination of contractile activity in guinea-pig mesenteric lymphatics.

    PubMed Central

    Crowe, M J; von der Weid, P Y; Brock, J A; Van Helden, D F

    1997-01-01

    1. Intraluminally perfused lymphatic vessels from the mesentery of the guinea-pig were examined in vitro to investigate their contractile activity and the co-ordination of this activity between adjacent lymphangions. 2. Lymphangions constricted at fairly regular intervals and exhibited 'refractory' periods of up to 3 s during which constrictions did not occur. 3. The contractile activity of adjacent lymphangions was highly co-ordinated. 4. The smooth muscle was found to be continuous between the adjacent lymphangions for the majority of valve regions examined morphologically (52 of 63 preparations). 5. Mechanical and electrical coupling between adjacent lymphangions was indicated, as some lymphangions underwent transient dilatations just prior to constriction, whereas direct electrophysiological measurements showed that the smooth muscle of most adjacent lymphangions was electrically coupled across the valve (15 out of 20 pairs of lymphangions). 6. It is concluded that perfused lymphangions of guinea-pig mesenteric lymphatic vessels rhythmically constrict, with the contractile activity of adjacent lymphangions highly co-ordinated. The findings also indicate that transmission of both mechanical and electrical signals between the adjacent lymphangions contribute to the co-ordination of their contractile activity. Images Figure 4 PMID:9097947

  9. Crosstalk between cancer cells and blood endothelial and lymphatic endothelial cells in tumour and organ microenvironment

    PubMed Central

    Lee, Esak; Pandey, Niranjan B.; Popel, Aleksander S.

    2015-01-01

    Tumour and organ microenvironments are crucial for cancer progression and metastasis. Crosstalk between multiple non-malignant cell types in the microenvironments and cancer cells promotes tumour growth and metastasis. Blood and lymphatic endothelial cells (BEC and LEC) are two of the components in the microenvironments. Tumour blood vessels (BV), comprising BEC, serve as conduits for blood supply into the tumour, and are important for tumour growth as well as haematogenous tumour dissemination. Lymphatic vessels (LV), comprising LEC, which are relatively leaky compared with BV, are essential for lymphogenous tumour dissemination. In addition to describing the conventional roles of the BV and LV, we also discuss newly emerging roles of these endothelial cells: their crosstalk with cancer cells via molecules secreted by the BEC and LEC (also called angiocrine and lymphangiocrine factors). This review suggests that BEC and LEC in various microenvironments can be orchestrators of tumour progression and proposes new mechanism-based strategies to discover new therapies to supplement conventional anti-angiogenic and anti-lymphangiogenic therapies. PMID:25634527

  10. Lymphatic drainage and CTV in pancreatic carcinoma.

    PubMed

    Morganti, Alessio G; Cellini, Numa; Mattiucci, Gian Carlo; Macchia, Gabriella; Smaniotto, Daniela; Luzi, Stefano; Balducci, Mario; Deodato, Francesco; Valentini, Vincenzo; Trodella, Lucio

    2003-01-01

    CTV definition in exclusive or adjuvant radiation therapy of pancreatic carcinoma is essentially based on the opinion of "expert" authors and on the knowledge of lymphatic pathways. The subject has been widely debated. Radiotherapy treatments of the entire upper abdomen (liver and pancreatic region), pancreas and lymph node stations, to volumes focused on macroscopic tumor only, have been proposed. Carcinoma of exocrine pancreas is characterized by the frequent, early appearance of metastasis via the lymphatic route. Most commonly involved lymph node stations include those of the celiac trunk, superior mesenteric, peripancreatic, lumboaortic lymph nodes, those of the hepatic portal (the latter in particular for pancreatic head tumors) and of the hilum of spleen (the latter in particular for pancreatic tail tumors). The possible multicentricity of pancreatic carcinoma, most likely due to intraductal spread, should lead to the inclusion in the CTV of the entire pancreatic parenchyma. This should be considered also for the frequent perineural intra- or extrapancreatic spread of pancreatic carcinoma present also in small tumors (T1). In extrapancreatic spread the retropancreatic adipose tissue should be included in the CTV at least at the GTV level. At the present state of knowledge, in the absence of pattern of failure analysis and of comparison of different treatment approaches, in terms of the definition of volumes of interest, CTV definitions which include lymphatic drainage stations, most part of pancreatic parenchyma and retropancreatic adipose tissue seem justified especially in treatments for cure. In palliation, the CTV may be limited to the GTV and the adipose tissue behind it. PMID:15018319

  11. Anatomy and physiology of lymphatic drainage of the breast from the perspective of sentinel node biopsy.

    PubMed

    Tanis, P J; Nieweg, O E; Valdés Olmos, R A; Kroon, B B

    2001-03-01

    Knowledge of the anatomy and physiology of the lymphatic system is helpful when considering a particular sentinel node biopsy technique. The delicate balance between internal and external pressures in a lymphatic channel can be influenced by the injection volume and by massage in a negative or positive way. The narrow openings in the interendothelial junctions determine the speed of clearance of particles with a certain size, and this has implications for the timing of lymphoscintigraphy and surgery. Tracer uptake and lymph flow are highly variable and depend on a number of factors, some of which are beyond our control. The lymphatic anatomy is not completely understood despite numerous studies since the end of the 18th century. Several topics have been elucidated in more recent studies and through experience with sentinel node biopsy. First, although axillary drainage is the principal lymphatic path of the breast, any drainage pattern from any quadrant of the breast can occur. Second, most lymph from the breast flows to the nodal basins with a direct course, not passing through the subareolar plexus. Another relevant point is that gentle massage encourages lymph flow and facilitates sentinel node detection. What problems do we still face in clinical practice? The optimum size and number of labeled colloid particles remain to be established. The optimum volume of the tracer also remains to be determined. But the main controversy concerns the injection site. Although the intradermal injection technique has attractive practical features, there is currently insufficient certainty that drainage of tracer injected anywhere in or underneath the skin of the breast reflects drainage from the cancer. Connections between collecting lymphatic vessels from the tumor site and the collecting vessels from the skin and subdermal lymphatics can explain the concordance between intraparenchymal and superficial injections in most patients. To determine the technique that yields the

  12. Lymphatic drug delivery using engineered liposomes and solid lipid nanoparticles

    PubMed Central

    Cai, Shuang; Zhang, Qiuhong; Bagby, Taryn; Forrest, M. Laird

    2011-01-01

    The lymphatic system plays a crucial role in the immune system’s recognition and response to disease, and most solid cancers initially spread from the primary site via the tumor’s surrounding lymphatics before hematological dissemination. Hence, the lymphatic system is an important target for developing new vaccines, cancer treatments, and diagnostic agents. Targeting the lymphatic system by subcutaneous, intestinal, and pulmonary routes has been evaluated and subsequently utilized to improve lymphatic penetration and retention of drug molecules, reduce drug-related systemic toxicities, and enhance bioavailability of poorly soluble and unstable drugs. Lymphatic imaging is an essential tool for the detection and staging of cancer. New nano-based technologies offer improved detection and characterization of the nodal diseases, while new delivery devices can better target and confine treatments to tumors within the nodal space while sparing healthy tissues. This manuscript reviews recent advances in the field of lymphatic drug delivery and imaging and focuses specifically on the development ofliposomes and solid lipid nanoparticles for lymphatic introduction via the subcutaneous, intestinal, and pulmonary routes. PMID:21712055

  13. Ventral Tegmental Area Afferents and Drug-Dependent Behaviors

    PubMed Central

    Oliva, Idaira; Wanat, Matthew J.

    2016-01-01

    Drug-related behaviors in both humans and rodents are commonly thought to arise from aberrant learning processes. Preclinical studies demonstrate that the acquisition and expression of many drug-dependent behaviors involves the ventral tegmental area (VTA), a midbrain structure comprised of dopamine, GABA, and glutamate neurons. Drug experience alters the excitatory and inhibitory synaptic input onto VTA dopamine neurons, suggesting a critical role for VTA afferents in mediating the effects of drugs. In this review, we present evidence implicating the VTA in drug-related behaviors, highlight the diversity of neuronal populations in the VTA, and discuss the behavioral effects of selectively manipulating VTA afferents. Future experiments are needed to determine which VTA afferents and what neuronal populations in the VTA mediate specific drug-dependent behaviors. Further studies are also necessary for identifying the afferent-specific synaptic alterations onto dopamine and non-dopamine neurons in the VTA following drug administration. The identification of neural circuits and adaptations involved with drug-dependent behaviors can highlight potential neural targets for pharmacological and deep brain stimulation interventions to treat substance abuse disorders. PMID:27014097

  14. Changes in monkey horizontal semicircular canal afferent responses after spaceflight

    NASA Technical Reports Server (NTRS)

    Correia, M. J.; Perachio, A. A.; Dickman, J. D.; Kozlovskaia, I. B.; Sirota, M. G.; Iakushin, S. B.; Beloozerova, I. N.

    1992-01-01

    Extracellular responses from single horizontal semicircular canal afferents in two rhesus monkeys were studied after recovery from a 14-day biosatellite (Cosmos 2044) orbital spaceflight. On the 1st postflight day, the mean gain for 9 different horizontal canal afferents, tested using one or several different passive yaw rotation waveforms, was nearly twice that for 20 horizontal canal afferents similarly tested during preflight and postflight control studies. Adaptation of the afferent response to passive yaw rotation on the 1st postflight day was also greater. These results suggest that at least one component of the vestibular end organ (the semicircular canals) is transiently modified after exposure to 14 days of microgravity. It is unclear whether the changes are secondary to other effects of microgravity, such as calcium loss, or an adaptive response. If the response is adaptive, then this report is the first evidence that the response of the vestibular end organ may be modified (presumably by the central nervous system via efferent connections) after prolonged unusual vestibular stimulation. If this is the case, the sites of plasticity of vestibular responses may not be exclusively within central nervous system vestibular structures, as previously believed.

  15. Osteopathic lymphatic pump techniques to enhance immunity and treat pneumonia

    PubMed Central

    Hodge, Lisa M.

    2012-01-01

    Pneumonia is a common cause of morbidity and mortality worldwide. While antibiotics are generally effective for the treatment of infection, the emergence of resistant strains of bacteria threatens their success. The osteopathic medical profession has designed a set of manipulative techniques called lymphatic pump techniques (LPT), to enhance the flow of lymph through the lymphatic system. Clinically, LPT is used to treat infection and oedemaand might be an effective adjuvant therapy in patients with pneumonia.The immune system uses the lymphatic and blood systems to survey to rid the body of pathogens; however, only recently have the effects of LPT on the lymphatic and immune systems been investigated. This short review highlightsclinical and basic science research studies that support the use of LPT to enhance the lymphatic and immune systems and treat pneumonia, and discusses the potential mechanisms by which LPT benefits patients with pneumonia. PMID:22977459

  16. Neck muscle afferents influence oromotor and cardiorespiratory brainstem neural circuits.

    PubMed

    Edwards, I J; Lall, V K; Paton, J F; Yanagawa, Y; Szabo, G; Deuchars, S A; Deuchars, J

    2015-01-01

    Sensory information arising from the upper neck is important in the reflex control of posture and eye position. It has also been linked to the autonomic control of the cardiovascular and respiratory systems. Whiplash associated disorders (WAD) and cervical dystonia, which involve disturbance to the neck region, can often present with abnormalities to the oromotor, respiratory and cardiovascular systems. We investigated the potential neural pathways underlying such symptoms. Simulating neck afferent activity by electrical stimulation of the second cervical nerve in a working heart brainstem preparation (WHBP) altered the pattern of central respiratory drive and increased perfusion pressure. Tracing central targets of these sensory afferents revealed projections to the intermedius nucleus of the medulla (InM). These anterogradely labelled afferents co-localised with parvalbumin and vesicular glutamate transporter 1 indicating that they are proprioceptive. Anterograde tracing from the InM identified projections to brain regions involved in respiratory, cardiovascular, postural and oro-facial behaviours--the neighbouring hypoglossal nucleus, facial and motor trigeminal nuclei, parabrachial nuclei, rostral and caudal ventrolateral medulla and nucleus ambiguus. In brain slices, electrical stimulation of afferent fibre tracts lateral to the cuneate nucleus monosynaptically excited InM neurones. Direct stimulation of the InM in the WHBP mimicked the response of second cervical nerve stimulation. These results provide evidence of pathways linking upper cervical sensory afferents with CNS areas involved in autonomic and oromotor control, via the InM. Disruption of these neuronal pathways could, therefore, explain the dysphagic and cardiorespiratory abnormalities which may accompany cervical dystonia and WAD. PMID:24595534

  17. Lymphatic albumin clearance from psoriatic skin

    SciTech Connect

    Staberg, B.; Klemp, P.; Aasted, M.; Worm, A.M.; Lund, P.

    1983-12-01

    In nine patients with untreated psoriasis vulgaris, human serum albumin labelled with /sup 125/I or /sup 131/I was injected intradermally in symmetrically located involved and uninvolved skin. The activity of the depots was followed by external detection, and the arrival of labelled albumin in plasma was monitored. In involved psoriatic skin the local mean half-time (T1/2) for tracer disappearance was 20.8 +/- 8.2 (S.D.) hr and in clinically normal skin, 29.1 +/- 9.6 (S.D.) hr. The difference was significant (p less than 0.002). Accordingly, the tracer from involved skin reached higher plasma levels than the tracer from uninvolved skin. However, under slight lymphatic stasis the appearance rate of radiolabelled albumin in plasma from both tissues was minimal during 1 to 2 hours after the injection, indicating that a local direct transvascular drainage of plasma albumin from the interstitium of diseased and normal skin was negligible. We conclude that the previously demonstrated increased extravasation of plasma proteins in involved psoriatic skin is compensated by an increased lymphatic drainage of plasma proteins, and not by an increased local transvascular return.

  18. Stress-driven lymphatic dissemination: An unanticipated consequence of communication between the sympathetic nervous system and lymphatic vasculature.

    PubMed

    Le, Caroline P; Sloan, Erica K

    2016-07-01

    Chronic stress drives cancer progression, but the routes of metastasis are unclear. We recently demonstrated that chronic stress activates a neural-inflammatory signaling axis to remodel lymphatic vasculature and increase lymph flow. This unanticipated crosstalk between stress and the lymphatic system provides pathways of tumor cell dissemination and accelerates metastasis. PMID:27652324

  19. A Novel Treatment Method for Lymph Node Metastasis Using a Lymphatic Drug Delivery System with Nano/Microbubbles and Ultrasound

    PubMed Central

    Kato, Shigeki; Mori, Shiro; Kodama, Tetsuya

    2015-01-01

    Chemotherapy based on hematogenous administration of drugs to lymph nodes (LNs) located outside the surgically resected area shows limited tissue selectivity and inadequate response rates, resulting in poor prognosis. Here, we demonstrate proof of concept for a lymphatic drug delivery system using nano/microbubbles (NMBs) and ultrasound (US) to achieve sonoporation in LNs located outside the dissection area. First, we demonstrated the in vitro effectiveness of doxorubicin (Dox) delivered into three different tumor cell lines by sonoporation. Sonoporation increased the Dox autofluorescence signal and resulted in a subsequent decrease in cell viability. Next, we verified the antitumor effects of Dox in vivo using MXH10/Mo-lpr/lpr mice that exhibit systemic lymphadenopathy, with some peripheral LNs reaching 10 mm in diameter. We defined the subiliac LN (SiLN) as the upstream LN within the dissection area, and the proper axillary LN (PALN) as the downstream LN outside the dissection area. Dox and NMBs were injected into the SiLN and delivered to the PALN via lymphatic vessels; the PALN was then exposed to US when it had filled with solution. We found that sonoporation enhanced the intracellular uptake of Dox leading to high cytotoxicity. We also found that sonoporation induced extravasation of Dox from lymphatic endothelia and penetration of Dox into tumor tissues within the PALN. Furthermore, our method inhibited tumor growth and diminished blood vessels in the PALN while avoiding systemic toxic effects of Dox. Our findings indicate that a lymphatic drug delivery system with sonoporation represents a promising method for treating metastatic LNs located outside the dissection area. PMID:26640589

  20. An Experimental Investigation of the Lymphatic System of the Teeth and Jaws

    PubMed Central

    MacGregor, Alexander

    1936-01-01

    A review of the literature is given, followed by a consideration of the available methods of demonstrating the lymphatic system in the area of the teeth and jaws. A new method of demonstrating this system by the injection or application of lead acetate intra vitam, is described, and the technique is explained. The method can be employed to reveal macroscopic or microscopic lymph channels in any part of the body, and is especially of value where decalcification of the hard tissues has to be carried out in the preparation of the sections. The various types of experiments which have been performed are described, and the macroscopic and microscopic results dealt with separately. Among the macroscopic results, the lymphatic drainage of various parts the jaws is described, and the large amount of anastomosis and cross anastomosis between the vessels is shown. A comparison of the lymphatic system in this region in the guinea-pig, cat, dog, and monkey is given, and it is demonstrated that the guinea-pig and monkey possess submental and supraclavicular lymph nodes which assist in the drainage of this area in addition to the submaxillary and cervical groups of nodes possessed by the cat and the dog. Among the microscopic results, the way in which the mass makes its way from the gingival tissues through the bone, and is found in the pulp, dentine, and cementum of the tooth, even where no pressure is applied, is described. The communication of the lymphatic vessels of the pulp with those of the periodontal membrane and the path of the mass down the periodontal membrane from the gingival trough, and its entry into the alveolar bone from this situation are demonstrated, and the way in which the mass reaches the pulp, dentine, and cementum of the tooth from the gingival tissues is discussed. The significance of various concentrations of the mass in the tissues, particularly the dentine, is also discussed. Control experiments are described, the conclusions which have been reached

  1. Thresholds of cutaneous afferents related to perceptual threshold across the human foot sole.

    PubMed

    Strzalkowski, Nicholas D J; Mildren, Robyn L; Bent, Leah R

    2015-10-01

    Perceptual thresholds are known to vary across the foot sole, despite a reported even distribution in cutaneous afferents. Skin mechanical properties have been proposed to account for these differences; however, a direct relationship between foot sole afferent firing, perceptual threshold, and skin mechanical properties has not been previously investigated. Using the technique of microneurography, we recorded the monofilament firing thresholds of cutaneous afferents and associated perceptual thresholds across the foot sole. In addition, receptive field hardness measurements were taken to investigate the influence of skin hardness on these threshold measures. Afferents were identified as fast adapting [FAI (n = 48) or FAII (n = 13)] or slowly adapting [SAI (n = 21) or SAII (n = 20)], and were grouped based on receptive field location (heel, arch, metatarsals, toes). Overall, perceptual thresholds were found to most closely align with firing thresholds of FA afferents. In contrast, SAI and SAII afferent firing thresholds were found to be significantly higher than perceptual thresholds and are not thought to mediate monofilament perceptual threshold across the foot sole. Perceptual thresholds and FAI afferent firing thresholds were significantly lower in the arch compared with other regions, and skin hardness was found to positively correlate with both FAI and FAII afferent firing and perceptual thresholds. These data support a perceptual influence of skin hardness, which is likely the result of elevated FA afferent firing threshold at harder foot sole sites. The close coupling between FA afferent firing and perceptual threshold across foot sole indicates that small changes in FA afferent firing can influence perceptual thresholds.

  2. Autoimmune antibodies in chronic lymphatic leukaemia.

    PubMed

    Lewis, C M; Pegrum, G D

    1978-01-01

    In chronic lymphocytic leukaemia a factor in patients' serum enhances the in vitro viability of the abnormal cells and this has been identified as an antibody. The activity of this factor can be removed by interaction with anti-immunoglobulin and by ammonium sulphate precipitation with a degree of saturation in excess of 46%. Cohn fractionation and chromatography with A-50 Sephadex show that the factor is not a complex but an immunoglobulin. No activity is removed after reaction of sera with 2-mercapto-ethanol and di-thiothreitol. The evidence therefore suggests that a gamma-G immunoglobulin is involved. Concentrated washings from the leukaemic cells behave in exactly the same way as patients' sera and activity is retained in the same fraction during precipitation and purification procedure. The extensive cross-reactivity of the sera suggests a common chronic lymphatic leukaemic antibody and it is considered that an active autoimmune response may be an integral part of the disease.

  3. Laparoscopic excision of a retroperitoneal lymphatic malformation in a newborn.

    PubMed

    Solari, Valeria; Mullassery, Dhanya; Lansdale, Nick; Jesudason, Edwin C

    2011-02-01

    Abdominal lymphatic malformations may be challenging to eradicate. Retroperitoneal lesions may more difficult to resect than mesenteric ones; however, the latter may predispose to intestinal volvulus, leading to calls for their prompt excision. Such lesions identified perinatally may pose particular challenges: in one case, respiratory failure caused by abdominal distension required emergency drainage followed by later laparoscopic excision; laparoscopy has also been used promptly to diagnose and resect neonatal mesenteric lymphatic malformations with their inherent volvulus risk. We illustrate that even if neonatal laparoscopy identifies a retroperitoneal rather than mesenteric lymphatic malformation, curative endosurgical excision remains feasible.

  4. In vivo dual-modality imaging of lymphatic systems using indocyanine green in rats: three-dimensional photoacoustic imaging and planar fluorescence imaging

    NASA Astrophysics Data System (ADS)

    Kim, Chulhong; Song, Kwang Hyun; Wang, Lihong V.

    2010-02-01

    The purpose of this study is to map non-invasively sentinel lymph nodes (SLNs) and lymphatic vessels of rats in vivo using FDA-approved indocyanine green (ICG) and two non-ionizing imaging modalities: volumetric spectroscopic photoacoustic (PA) imaging, which measures optical absorption, and planar fluorescence imaging, which measures fluorescent emission. SLNs and lymphatic vessels were clearly visible after a 0.2 ml-intradermal-injection of 1 mM ICG in both imaging systems. We also imaged deeply positioned lymph nodes in vivo by layering biological tissues on top of rats. These two modalities, when used together with ICG, have the potential to map SLNs in axillary staging and to study tumor metastasis in breast cancer patients.

  5. Distinct recurrent versus afferent dynamics in cortical visual processing.

    PubMed

    Reinhold, Kimberly; Lien, Anthony D; Scanziani, Massimo

    2015-12-01

    How intracortical recurrent circuits in mammalian sensory cortex influence dynamics of sensory representation is not understood. Previous methods could not distinguish the relative contributions of recurrent circuits and thalamic afferents to cortical dynamics. We accomplish this by optogenetically manipulating thalamus and cortex. Over the initial 40 ms of visual stimulation, excitation from recurrent circuits in visual cortex progressively increased to exceed direct thalamocortical excitation. Even when recurrent excitation exceeded thalamic excitation, upon silencing thalamus, sensory-evoked activity in cortex decayed rapidly, with a time constant of 10 ms, which is similar to a neuron's integration time window. In awake mice, this cortical decay function predicted the time-locking of cortical activity to thalamic input at frequencies <15 Hz and attenuation of the cortical response to higher frequencies. Under anesthesia, depression at thalamocortical synapses disrupted the fidelity of sensory transmission. Thus, we determine dynamics intrinsic to cortical recurrent circuits that transform afferent input in time.

  6. Predictive lymphatic mapping: a method for mapping lymphatic channels in patients with advanced unilateral lymphedema using indocyanine green lymphography.

    PubMed

    Mihara, Makoto; Seki, Yukio; Hara, Hisako; Iida, Takuya; Oka, Aiko; Kikuchi, Kazuki; Narushima, Mitsunaga; Haragi, Makiko; Furniss, Dominic; Hin-Lun, Lawrence; Mitsui, Kito; Murai, Noriyuki; Koshima, Isao

    2014-01-01

    In severe lymphedema, indocyanine green lymphography cannot be used to map lymphatic channels before lymphaticovenular anastomosis (LVA) because linear lymphatics cannot be detected in a severely affected leg. Here, we describe a new method, which we refer to as predictive lymphatic mapping, to predict the location of lymphatics for anastomosis in unilateral lymphedema, thereby improving surgical accuracy and efficiency. The approach consists of marking anatomical landmarks and joining selected landmarks with fixed lines. The distance from these fixed lines to lymphatic channels mapped by indocyanine green lymphography in the unaffected leg is then measured, scaled up based on the difference in circumference between the legs, and transposed to the affected leg. To date, we have used this method in 5 cases of unilateral or asymmetric lymphedema of the lower extremities. In no cases have we failed to find a lymphatic channel suitable for LVA within a 2-cm incision. These results suggest that predictive lymphatic mapping is a useful additional tool for surgeons performing LVA under local anesthesia, which will help to improve the accuracy of incisions and the efficiency of surgery.

  7. Coding of stimuli by ampullary afferents in Gnathonemus petersii.

    PubMed

    Engelmann, J; Gertz, S; Goulet, J; Schuh, A; von der Emde, G

    2010-10-01

    Weakly electric fish use electroreception for both active and passive electrolocation and for electrocommunication. While both active and passive electrolocation systems are prominent in weakly electric Mormyriform fishes, knowledge of their passive electrolocation ability is still scarce. To better estimate the contribution of passive electric sensing to the orientation toward electric stimuli in weakly electric fishes, we investigated frequency tuning applying classical input-output characterization and stimulus reconstruction methods to reveal the encoding capabilities of ampullary receptor afferents. Ampullary receptor afferents were most sensitive (threshold: 40 μV/cm) at low frequencies (<10 Hz) and appear to be tuned to a mix of amplitude and slope of the input signals. The low-frequency tuning was corroborated by behavioral experiments, but behavioral thresholds were one order of magnitude higher. The integration of simultaneously recorded afferents of similar frequency-tuning resulted in strongly enhanced signal-to-noise ratios and increased mutual information rates but did not increase the range of frequencies detectable by the system. Theoretically the neuronal integration of input from receptors experiencing opposite polarities of a stimulus (left and right side of the fish) was shown to enhance encoding of such stimuli, including an increase of bandwidth. Covariance and coherence analysis showed that spiking of ampullary afferents is sufficiently explained by the spike-triggered average, i.e., receptors respond to a single linear feature of the stimulus. Our data support the notion of a division of labor of the active and passive electrosensory systems in weakly electric fishes based on frequency tuning. Future experiments will address the role of central convergence of ampullary input that we expect to lead to higher sensitivity and encoding power of the system. PMID:20685928

  8. Renal afferents signaling diuretic activity in the cat.

    PubMed

    Genovesi, S; Pieruzzi, F; Wijnmaalen, P; Centonza, L; Golin, R; Zanchetti, A; Stella, A

    1993-11-01

    Mechanoreceptors and chemoreceptors have been identified inside the kidney, but their functional role is still largely unclear. The aim of this study was to investigate whether changes in urine output could modify the discharge rate of renal afferent fibers. Experiments were performed in anesthetized cats in which afferent renal nerve activity (ARNA) was recorded by standard electrophysiological techniques from a centrally cut renal nerve. Arterial pressure, renal blood flow velocity, urine flow rate, and renal pelvic pressure were also measured. Three diuretic maneuvers were tested in the same cat: intravenous administration of physiological saline (8 to 13 mL/min for 2 minutes), furosemide (1 mg/kg), and atrial natriuretic peptide (ANP, 1 microgram/kg). The three maneuvers increased urine flow rate and pelvic pressure, respectively, 137.0 +/- 20.6% and 136.8 +/- 21.1% (saline), 148.6 +/- 31.7% and 139.6 +/- 43.5% (furosemide), and 75.9 +/- 7.9% and 62.1 +/- 21.2% (ANP) at the time of the maximum response. Arterial pressure slightly increased after saline, did not change after furosemide, and slightly decreased after ANP. Renal blood flow increased after saline and did not change after furosemide and ANP. The three maneuvers increased ARNA by 98.4 +/- 15.2% (saline), 270.7 +/- 100.8% (furosemide), and 59.6 +/- 23.4% (ANP). Changes in ARNA significantly correlate with changes in both pelvic pressure and urine flow rate. Our data demonstrate that increments in urine flow rate increase the firing rate of renal afferent fibers and suggest that (1) pelvic pressure is the major determinant of the neural response, and (2) this increased afferent discharge is due to activation of renal mechanoreceptors.

  9. Neuropathic pain: Early spontaneous afferent activity is the trigger

    PubMed Central

    Xie, Wenrui; Strong, Judith A.; Meij, Johanna T.A.; Zhang, Jun-Ming; Yu, Lei

    2005-01-01

    Intractable neuropathic pain often results from nerve injury. One immediate event in damaged nerve is a sustained increase in spontaneous afferent activity, which has a well-established role in ongoing pain. Using two rat models of neuropathic pain, the CCI and SNI models, we show that local, temporary nerve blockade of this afferent activity permanently inhibits the subsequent development of both thermal hyperalgesia and mechanical allodynia. Timing is critical—the nerve blockade must last at least 3–5 days and is effective if started immediately after nerve injury, but not if started at 10 days after injury when neuropathic pain is already established. Effective nerve blockade also prevents subsequent development of spontaneous afferent activity measured electrophysiologically. Similar results were obtained in both pain models, and with two blockade methods (200 mg of a depot form bupivacaine at the injury site, or perfusion of the injured nerve just proximal to the injury site with TTX). These results indicate that early spontaneous afferent fiber activity is the key trigger for the development of pain behaviors, and suggest that spontaneous activity may be required for many of the later changes in the sensory neurons, spinal cord, and brain observed in neuropathic pain models. Many pre-clinical and clinical studies of pre-emptive analgesia have used much shorter duration of blockade, or have not started immediately after the injury. Our results suggest that effective pre-emptive analgesia can be achieved only when nerve block is administered early after injury and lasts several days. PMID:15964687

  10. ADAM17 Promotes Motility, Invasion, and Sprouting of Lymphatic Endothelial Cells.

    PubMed

    Mężyk-Kopeć, Renata; Wyroba, Barbara; Stalińska, Krystyna; Próchnicki, Tomasz; Wiatrowska, Karolina; Kilarski, Witold W; Swartz, Melody A; Bereta, Joanna

    2015-01-01

    Tumor-associated lymphatic vessels actively participate in tumor progression and dissemination. ADAM17, a sheddase for numerous growth factors, cytokines, receptors, and cell adhesion molecules, is believed to promote tumor development, facilitating both tumor cell proliferation and migration, as well as tumor angiogenesis. In this work we addressed the issue of whether ADAM17 may also promote tumor lymphangiogenesis. First, we found that ADAM17 is important for the migratory potential of immortalized human dermal lymphatic endothelial cells (LEC). When ADAM17 was stably silenced in LEC, their proliferation was not affected, but: (i) single-cell motility, (ii) cell migration through a 3D Matrigel/collagen type I matrix, and (iii) their ability to form sprouts in a 3D matrix were significantly diminished. The differences in the cell motility between ADAM17-proficient and ADAM17-silenced cells were eliminated by inhibitors of EGFR and HER2, indicating that ADAM17-mediated shedding of growth factors accounts for LEC migratory potential. Interestingly, ADAM17 depletion affected the integrin surface expression/functionality in LEC. ADAM17-silenced cells adhered to plastic, type I collagen, and fibronectin faster than their ADAM17-proficient counterparts. The difference in adhesion to fibronectin was abolished by a cyclic RGD peptide, emphasizing the involvement of integrins in the process. Using a soluble receptor array, we identified BIG-H3 among several candidate proteins involved in the phenotypic and behavioral changes of LEC upon ADAM17 silencing. In additional assays, we confirmed the increased expression of BIG-H3, as well as TGFβ2 in ADAM17-silenced LEC. The antilymphangiogenic effects of ADAM17 silencing in lymphatic endothelial cells suggest further relevance of ADAM17 as a potential target in cancer therapy. PMID:26176220

  11. ADAM17 Promotes Motility, Invasion, and Sprouting of Lymphatic Endothelial Cells

    PubMed Central

    Stalińska, Krystyna; Próchnicki, Tomasz; Wiatrowska, Karolina; Kilarski, Witold W.; Swartz, Melody A.; Bereta, Joanna

    2015-01-01

    Tumor-associated lymphatic vessels actively participate in tumor progression and dissemination. ADAM17, a sheddase for numerous growth factors, cytokines, receptors, and cell adhesion molecules, is believed to promote tumor development, facilitating both tumor cell proliferation and migration, as well as tumor angiogenesis. In this work we addressed the issue of whether ADAM17 may also promote tumor lymphangiogenesis. First, we found that ADAM17 is important for the migratory potential of immortalized human dermal lymphatic endothelial cells (LEC). When ADAM17 was stably silenced in LEC, their proliferation was not affected, but: (i) single-cell motility, (ii) cell migration through a 3D Matrigel/collagen type I matrix, and (iii) their ability to form sprouts in a 3D matrix were significantly diminished. The differences in the cell motility between ADAM17-proficient and ADAM17-silenced cells were eliminated by inhibitors of EGFR and HER2, indicating that ADAM17-mediated shedding of growth factors accounts for LEC migratory potential. Interestingly, ADAM17 depletion affected the integrin surface expression/functionality in LEC. ADAM17-silenced cells adhered to plastic, type I collagen, and fibronectin faster than their ADAM17-proficient counterparts. The difference in adhesion to fibronectin was abolished by a cyclic RGD peptide, emphasizing the involvement of integrins in the process. Using a soluble receptor array, we identified BIG-H3 among several candidate proteins involved in the phenotypic and behavioral changes of LEC upon ADAM17 silencing. In additional assays, we confirmed the increased expression of BIG-H3, as well as TGFβ2 in ADAM17-silenced LEC. The antilymphangiogenic effects of ADAM17 silencing in lymphatic endothelial cells suggest further relevance of ADAM17 as a potential target in cancer therapy. PMID:26176220

  12. ADAM17 Promotes Motility, Invasion, and Sprouting of Lymphatic Endothelial Cells.

    PubMed

    Mężyk-Kopeć, Renata; Wyroba, Barbara; Stalińska, Krystyna; Próchnicki, Tomasz; Wiatrowska, Karolina; Kilarski, Witold W; Swartz, Melody A; Bereta, Joanna

    2015-01-01

    Tumor-associated lymphatic vessels actively participate in tumor progression and dissemination. ADAM17, a sheddase for numerous growth factors, cytokines, receptors, and cell adhesion molecules, is believed to promote tumor development, facilitating both tumor cell proliferation and migration, as well as tumor angiogenesis. In this work we addressed the issue of whether ADAM17 may also promote tumor lymphangiogenesis. First, we found that ADAM17 is important for the migratory potential of immortalized human dermal lymphatic endothelial cells (LEC). When ADAM17 was stably silenced in LEC, their proliferation was not affected, but: (i) single-cell motility, (ii) cell migration through a 3D Matrigel/collagen type I matrix, and (iii) their ability to form sprouts in a 3D matrix were significantly diminished. The differences in the cell motility between ADAM17-proficient and ADAM17-silenced cells were eliminated by inhibitors of EGFR and HER2, indicating that ADAM17-mediated shedding of growth factors accounts for LEC migratory potential. Interestingly, ADAM17 depletion affected the integrin surface expression/functionality in LEC. ADAM17-silenced cells adhered to plastic, type I collagen, and fibronectin faster than their ADAM17-proficient counterparts. The difference in adhesion to fibronectin was abolished by a cyclic RGD peptide, emphasizing the involvement of integrins in the process. Using a soluble receptor array, we identified BIG-H3 among several candidate proteins involved in the phenotypic and behavioral changes of LEC upon ADAM17 silencing. In additional assays, we confirmed the increased expression of BIG-H3, as well as TGFβ2 in ADAM17-silenced LEC. The antilymphangiogenic effects of ADAM17 silencing in lymphatic endothelial cells suggest further relevance of ADAM17 as a potential target in cancer therapy.

  13. Pdgfrb‐Cre targets lymphatic endothelial cells of both venous and non‐venous origins

    PubMed Central

    Ulvmar, Maria H.; Martinez‐Corral, Ines; Stanczuk, Lukas

    2016-01-01

    Abstract The Pdgfrb‐Cre line has been used as a tool to specifically target pericytes and vascular smooth muscle cells. Recent studies showed additional targeting of cardiac and mesenteric lymphatic endothelial cells (LECs) by the Pdgfrb‐Cre transgene. In the heart, this was suggested to provide evidence for a previously unknown nonvenous source of LECs originating from yolk sac (YS) hemogenic endothelium (HemEC). Here we show that Pdgfrb‐Cre does not, however, target YS HemEC or YS‐derived erythro‐myeloid progenitors (EMPs). Instead, a high proportion of ECs in embryonic blood vessels of multiple organs, as well as venous‐derived LECs were targeted. Assessment of temporal Cre activity using the R26‐mTmG double reporter suggested recent occurrence of Pdgfrb‐Cre recombination in both blood and lymphatic ECs. It thus cannot be excluded that Pdgfrb‐Cre mediated targeting of LECs is due to de novo expression of the Pdgfrb‐Cre transgene or their previously established venous endothelial origin. Importantly, Pdgfrb‐Cre targeting of LECs does not provide evidence for YS HemEC origin of the lymphatic vasculature. Our results highlight the need for careful interpretation of lineage tracing using constitutive Cre lines that cannot discriminate active from historical expression. The early vascular targeting by the Pdgfrb‐Cre also warrants consideration for its use in studies of mural cells. genesis 54:350–358, 2016. © 2016 The Authors. Genesis Published by Wiley Periodicals, Inc. PMID:27060598

  14. Subcortical afferent connections of the amygdala in the monkey

    NASA Technical Reports Server (NTRS)

    Mehler, W. R.

    1980-01-01

    The cells of origin of the afferent connections of the amygdala in the rhesus and squirrel monkeys are determined according to the retrograde axonal transport of the enzyme horseradish peroxidase injected into various quadrants of the amygdala. Analysis of the distribution of enzyme-labeled cells reveals afferent amygdalar connections with the ipsilateral halves of the midline nucleus paraventricularis thalami and both the parvo- and magnocellular parts of the nucleus subparafascicularis in the dorsal thalamus, all the subdivisions of the midline nucleus centralis complex, the nucleus reuniens ventralis and the nucleus interventralis. The largest populations of enzyme-labeled cells in the hypothalamus are found to lie in the middle and posterior parts of the ipsilateral, lateral hypothalamus and the ventromedial hypothalamic nucleus, with scattered cells in the supramammillary and dorsomedial nuclei and the posterior hypothalamic area, Tsai's ventral tegmental area, the rostral and caudal subdivisions of the nucleus linearis in the midbrain and the dorsal raphe nucleus. The most conspicuous subdiencephalic source of amygdalar afferent connections is observed to be the pars lateralis of the nucleus parabrachialis in the dorsolateral pontine tegmentum, with a few labeled cells differentiated from pigmented cells in the locus coeruleus.

  15. Neck afferent involvement in cardiovascular control during movement

    NASA Technical Reports Server (NTRS)

    Bolton, P. S.; Ray, C. A.

    2000-01-01

    It is well established that labyrinth and neck afferent information contributes to the regulation of somatomotor function during movement and changes in posture. There is also convincing evidence that the vestibular system participates in the modulation of sympathetic outflow and cardiovascular function during changes in posture, presumably to prevent orthostatic hypotension. However, the labyrinth organs do not provide any signals concerning body movements with respect to the head. In contrast, the neck receptors, particularly muscle spindles, are well located and suited to provide information about changes in body position with respect to the head and vestibular signals. Studies in the cat suggest that neck afferent information may modulate the vestibulosympathetic reflex responses to head-neck movements. There is some evidence in the cat to suggest involvement of low threshold mechanoreceptors. However, human studies do not indicate that low threshold mechanoreceptors in the neck modulate cardiovascular responses. The human studies are consistent with the studies in the cat in that they demonstrate the importance of otolith activation in mediating cardiovascular and sympathetic responses to changes in posture. This paper briefly reviews the current experimental evidence concerning the involvement of neck afferent information in the modulation of cardiovascular control during movement and changes in posture.

  16. Transfer characteristics of the hair cell's afferent synapse

    NASA Astrophysics Data System (ADS)

    Keen, Erica C.; Hudspeth, A. J.

    2006-04-01

    The sense of hearing depends on fast, finely graded neurotransmission at the ribbon synapses connecting hair cells to afferent nerve fibers. The processing that occurs at this first chemical synapse in the auditory pathway determines the quality and extent of the information conveyed to the central nervous system. Knowledge of the synapse's input-output function is therefore essential for understanding how auditory stimuli are encoded. To investigate the transfer function at the hair cell's synapse, we developed a preparation of the bullfrog's amphibian papilla. In the portion of this receptor organ representing stimuli of 400-800 Hz, each afferent nerve fiber forms several synaptic terminals onto one to three hair cells. By performing simultaneous voltage-clamp recordings from presynaptic hair cells and postsynaptic afferent fibers, we established that the rate of evoked vesicle release, as determined from the average postsynaptic current, depends linearly on the amplitude of the presynaptic Ca2+ current. This result implies that, for receptor potentials in the physiological range, the hair cell's synapse transmits information with high fidelity. auditory system | exocytosis | glutamate | ribbon synapse | synaptic vesicle

  17. Putative roles of neuropeptides in vagal afferent signaling

    PubMed Central

    de Lartigue, Guillaume

    2014-01-01

    The vagus nerve is a major pathway by which information is communicated between the brain and peripheral organs. Sensory neurons of the vagus are located in the nodose ganglia. These vagal afferent neurons innervate the heart, the lung and the gastrointestinal tract, and convey information about peripheral signals to the brain important in the control of cardiovascular tone, respiratory tone, and satiation, respectively. Glutamate is thought to be the primary neurotransmitter involved in conveying all of this information to the brain. It remains unclear how a single neurotransmitter can regulate such an extensive list of physiological functions from a wide range of visceral sites. Many neurotransmitters have been identified in vagal afferent neurons and have been suggested to modulate the physiological functions of glutamate. Specifically, the anorectic peptide transmitters, cocaine and amphetamine regulated transcript (CART) and the orexigenic peptide transmitters, melanin concentrating hormone (MCH) are differentially regulated in vagal afferent neurons and have opposing effects on food intake. Using these two peptides as a model, this review will discuss the potential role of peptide transmitters in providing a more precise and refined modulatory control of the broad physiological functions of glutamate, especially in relation to the control of feeding. PMID:24650553

  18. Characterization of Mouse Lumbar Splanchnic and Pelvic Nerve Urinary Bladder Mechanosensory Afferents

    PubMed Central

    Xu, Linjing; Gebhart, G. F.

    2009-01-01

    Sensory information from the urinary bladder is conveyed via lumbar splanchnic (LSN) and sacral pelvic (PN) nerves to the spinal cord. In the present report we compared the mechanosensitive properties of single afferent fibers in these two pathways using an in vitro mouse bladder preparation. Mechanosensitive primary afferents were recorded from the LSN or PN and distinguished based on their response to receptive field stimulation with different mechanical stimuli: probing (160 mg to 2 g), stretch (1–25 g), and stroking of the urothelium (10–1,000 mg). Four different classes of afferent were recorded from the LSN and PN: serosal, muscular, muscular/urothielial, and urothelial. The LSN contained principally serosal and muscular afferents (97% of the total sample), whereas all four afferent classes of afferent were present in the PN (63% of which were muscular afferents). In addition, the respective proportions and receptive field distributions differed between the two pathways. Both low- and high-threshold stretch-sensitive muscular afferents were present in both pathways, and muscular afferents in the PN were shown to sensitize after exposure to an inflammatory soup cocktail. The LSN and PN pathways contain different populations of mechanosensitive afferents capable of detecting a range of mechanical stimuli and individually tuned to detect the type, magnitude, and duration of the stimulus. This knowledge broadens our understanding of the potential roles these two pathways play in conveying mechanical information from the bladder to the spinal cord. PMID:18003875

  19. Vestibular afferent responses to linear accelerations in the alert squirrel monkey

    NASA Technical Reports Server (NTRS)

    Somps, Christopher J.; Schor, Robert H.; Tomko, David L.

    1994-01-01

    The spontaneous activity of 40 otolith afferents and 44 canal afferents was recorded in 4 alert, intact squirrel monkeys. Polarization vectors and response properties of otolith afferents were determined during static re-orientations relative to gravity and during Earth-horizontal, sinusoidal, linear oscillations. Canal afferents were tested for sensitivity to linear accelerations. For regular otolith afferents, a significant correlation between upright discharge rate and sensitivity to dynamic acceleration in the horizontal plane was observed. This correlation was not present in irregular units. The sensitivity of otolith afferents to both static tilts and dynamic linear acceleration was much greater in irregularly discharging units than in regularly discharging units. The spontaneous activity and static and dynamic response properties of regularly discharging otolith afferents were similar to those reported in barbiturate-anesthetized squirrel monkeys. Irregular afferents also had similar dynamic response properties when compared to anesthetized monkeys. However, this sample of irregular afferents in alert animals had higher resting discharge rates and greater sensitivity to static tilts. The majority of otolith polarization vectors were oriented near the horizontal in the plane of the utricular maculae; however, directions of maximum sensitivity were different during dynamic and static testing. Canal afferents were not sensitive to static tilts or linear oscillations of the head.

  20. Intact cutaneous C fibre afferent properties in mechanical and cold neuropathic allodynia

    PubMed Central

    Hulse, Richard; Wynick, David; Donaldson, Lucy F.

    2010-01-01

    Patients with neuropathy, report changes in sensory perception, particularly mechanical and thermal allodynia, and spontaneous pain. Similar sensory changes are seen in experimental neuropathies, in which alteration in primary afferent properties can also be determined. The neural correlate of spontaneous pain is ongoing activity in sensory afferents. Mechanical and heat allodynia are thought to result from lowered activation thresholds in primary afferent and/or central neurones, but the mechanisms underlying cold allodynia are very poorly understood. We investigated nociceptive behaviours and the properties of C and A fibre intact afferents running adjacent to damaged afferents following a partial ligation injury of the saphenous nerve (PSNI). Animals developed mechanical and cold allodynia by 3 days after PSNI. Intact mechanosensitive C fibre afferents developed ongoing activity, and had slower conduction velocities 3 and 7 days following nerve injury, with no change in mechanical threshold. There was a large increase (∼46-fold) in calculated afferent input 3 days after nerve injury, as a result of the ongoing activity in these fibres. Mechano-cooling-sensitive C fibre afferents showed both enhanced cooling-evoked firing, and increased ongoing activity. The afferent barrage associated with mechano-cooling-sensitive afferents was increased 26-fold 7 days after nerve injury. We observed no differences in the properties of intact A fibre mechanosensitive afferents. These studies demonstrate for the first time that the altered nociception seen after PSNI is associated with ongoing activity and enhanced cooling-evoked activity in intact C fibre afferents in the saphenous nerve, with no concurrent alteration in A fibre afferents. PMID:19942464

  1. Isolation and Characterization of Human Lung Lymphatic Endothelial Cells.

    PubMed

    Lorusso, Bruno; Falco, Angela; Madeddu, Denise; Frati, Caterina; Cavalli, Stefano; Graiani, Gallia; Gervasi, Andrea; Rinaldi, Laura; Lagrasta, Costanza; Maselli, Davide; Gnetti, Letizia; Silini, Enrico M; Quaini, Eugenio; Ampollini, Luca; Carbognani, Paolo; Quaini, Federico

    2015-01-01

    Characterization of lymphatic endothelial cells from the respiratory system may be crucial to investigate the role of the lymphatic system in the normal and diseased lung. We describe a simple and inexpensive method to harvest, isolate, and expand lymphatic endothelial cells from the human lung (HL-LECs). Fifty-five samples of healthy lung selected from patients undergoing lobectomy were studied. A two-step purification tool, based on paramagnetic sorting with monoclonal antibodies to CD31 and Podoplanin, was employed to select a pure population of HL-LECs. The purity of HL-LECs was assessed by morphologic criteria, immunocytochemistry, flow cytometry, and functional assays. Interestingly, these cells retain in vitro several receptor tyrosine kinases (RTKs) implicated in cell survival and proliferation. HL-LECs represent a clinically relevant cellular substrate to study lymphatic biology, lymphoangiogenesis, interaction with microbial agents, wound healing, and anticancer therapy. PMID:26137493

  2. Isolation and Characterization of Human Lung Lymphatic Endothelial Cells

    PubMed Central

    Lorusso, Bruno; Falco, Angela; Madeddu, Denise; Frati, Caterina; Cavalli, Stefano; Graiani, Gallia; Gervasi, Andrea; Rinaldi, Laura; Lagrasta, Costanza; Maselli, Davide; Gnetti, Letizia; Silini, Enrico M.; Quaini, Eugenio; Ampollini, Luca; Carbognani, Paolo; Quaini, Federico

    2015-01-01

    Characterization of lymphatic endothelial cells from the respiratory system may be crucial to investigate the role of the lymphatic system in the normal and diseased lung. We describe a simple and inexpensive method to harvest, isolate, and expand lymphatic endothelial cells from the human lung (HL-LECs). Fifty-five samples of healthy lung selected from patients undergoing lobectomy were studied. A two-step purification tool, based on paramagnetic sorting with monoclonal antibodies to CD31 and Podoplanin, was employed to select a pure population of HL-LECs. The purity of HL-LECs was assessed by morphologic criteria, immunocytochemistry, flow cytometry, and functional assays. Interestingly, these cells retain in vitro several receptor tyrosine kinases (RTKs) implicated in cell survival and proliferation. HL-LECs represent a clinically relevant cellular substrate to study lymphatic biology, lymphoangiogenesis, interaction with microbial agents, wound healing, and anticancer therapy. PMID:26137493

  3. Lymphatic dysfunction after ligation surgery for varicose vein

    PubMed Central

    Hara, Hisako; Mihara, Makoto; Hasegawa, Kyoko; Yamanaka, Kazuko

    2016-01-01

    Objective: Although the lymphatic complications such as lymphocele sometimes occur after surgery for varicose veins, the lymphatic function of such patients has not been evaluated. In this case report, we present a case of lymphocele after ligation surgery for varicose vein. We also detected subclinical dysfunction in lower limb using indocyanine green (ICG) lymphography. Case report: A 76 year- old female underwent ligation surgery for right lower leg varicose vein, and she noticed the squashy lesion in the medial side of the right knee. Three years later, she consulted our clinic and we performed ICG lymphography. We observed dermal backflow around the mass, which indicated lymphatic dysfunction. After injecting additional ICG around the knee, we punctured and drained the clear, yellow fluid from the mass and it was contrasted with ICG during the examination and the involvement of the lymphatic system was proven. PMID:27757234

  4. Current and Future Lymphatic Imaging Modalities for Tumor Staging

    PubMed Central

    Gao, Kuo; Liu, Tiegang; Tariq, Imran; Sajjad, Ashif; Niu, Meiying; Liu, Guokai; Mehmood, Zahid; Tian, Guihua

    2014-01-01

    Tumor progression is supported by the lymphatic system which should be scanned efficiently for tumor staging as well as the enhanced therapeutic outcomes. Poor resolution and low sensitivity is a limitation of traditional lymphatic imaging modalities; thus new noninvasive approaches like nanocarriers, magnetic resonance imaging, positron-emission tomography, and quantum dots are advantageous. Some newer modalities, which are under development, and their potential uses will also be discussed in this review. PMID:24757671

  5. Morphological and Molecular Characterization of Human Dermal Lymphatic Collectors

    PubMed Central

    Buttler, Kerstin; Ströbel, Philipp; Becker, Jürgen; Aung, Thiha; Felmerer, Gunther; Wilting, Jörg

    2016-01-01

    Millions of patients suffer from lymphedema worldwide. Supporting the contractility of lymphatic collectors is an attractive target for pharmacological therapy of lymphedema. However, lymphatics have mostly been studied in animals, while the cellular and molecular characteristics of human lymphatic collectors are largely unknown. We studied epifascial lymphatic collectors of the thigh, which were isolated for autologous transplantations. Our immunohistological studies identify additional markers for LECs (vimentin, CCBE1). We show and confirm differences between initial and collecting lymphatics concerning the markers ESAM1, D2-40 and LYVE-1. Our transmission electron microscopic studies reveal two types of smooth muscle cells (SMCs) in the media of the collectors with dark and light cytoplasm. We observed vasa vasorum in the media of the largest collectors, as well as interstitial Cajal-like cells, which are highly ramified cells with long processes, caveolae, and lacking a basal lamina. They are in close contact with SMCs, which possess multiple caveolae at the contact sites. Immunohistologically we identified such cells with antibodies against vimentin and PDGFRα, but not CD34 and cKIT. With Next Generation Sequencing we searched for highly expressed genes in the media of lymphatic collectors, and found therapeutic targets, suitable for acceleration of lymphatic contractility, such as neuropeptide Y receptors 1, and 5; tachykinin receptors 1, and 2; purinergic receptors P2RX1, and 6, P2RY12, 13, and 14; 5-hydroxytryptamine receptors HTR2B, and 3C; and adrenoceptors α2A,B,C. Our studies represent the first comprehensive characterization of human epifascial lymphatic collectors, as a prerequisite for diagnosis and therapy. PMID:27764183

  6. Theranostic mRNA-loaded Microbubbles in the Lymphatics of Dogs: Implications for Drug Delivery

    PubMed Central

    Dewitte, Heleen; Vanderperren, Katrien; Haers, Hendrik; Stock, Emmelie; Duchateau, Luc; Hesta, Myriam; Saunders, Jimmy H.; De Smedt, Stefaan C.; Lentacker, Ine

    2015-01-01

    Microbubbles have shown potential as intralymphatic ultrasound contrast agents while nanoparticle-loaded microbubbles are increasingly investigated for ultrasound-triggered drug and gene delivery. To explore whether mRNA-nanoparticle loaded microbubbles could serve as theranostics for detection of and mRNA transfer to the lymph nodes, we investigate the behavior of unloaded and mRNA-loaded microbubbles using contrast-enhanced ultrasound imaging after subcutaneous injection in dogs. Our results indicate that both types of microbubbles are equally capable of rapidly entering the lymph vessels and nodes upon injection, and novel, valuable and detailed information on the lymphatic structure in the animals could be obtained. Furthermore, additional observations were made regarding the dynamics of microbubble lymph node uptake. Importantly, neither the microbubble migration distance within the lymphatics, nor the observed contrast signal intensity was influenced by mRNA-loading. Although further optimization of acoustic parameters will be needed, this could represent a first step towards ultrasound-guided, ultrasound-triggered intranodal mRNA delivery using these theranostic microbubbles. PMID:25553101

  7. Quantum dots trace lymphatic drainage from the mouse eye

    NASA Astrophysics Data System (ADS)

    Tam, Alex L. C.; Gupta, Neeru; Zhang, Zhexue; Yücel, Yeni H.

    2011-10-01

    Glaucoma is a leading cause of blindness in the world, often associated with elevated eye pressure. Currently, all glaucoma treatments aim to lower eye pressure by improving fluid exit from the eye. We recently reported the presence of lymphatics in the human eye. The lymphatic circulation is known to drain fluid from organ tissues and, as such, lymphatics may also play a role in draining fluid from the eye. We investigated whether lymphatic drainage from the eye is present in mice by visualizing the trajectory of quantum dots once injected into the eye. Whole-body hyperspectral fluorescence imaging was performed in 17 live mice. In vivo imaging was conducted prior to injection, and 5, 20, 40 and 70 min, and 2, 6 and 24 h after injection. A quantum dot signal was observed in the left neck region at 6 h after tracer injection into the eye. Examination of immunofluorescence-labelled sections using confocal microscopy showed the presence of a quantum dot signal in the left submandibular lymph node. This is the first direct evidence of lymphatic drainage from the mouse eye. The use of quantum dots to image this lymphatic pathway in vivo is a novel tool to stimulate new treatments to reduce eye pressure and prevent blindness from glaucoma.

  8. Angiotensin II receptors in rabbit renal preglomerular vessels

    SciTech Connect

    Brown, G.P.; Venuto, R.C. )

    1988-07-01

    Controversy exists regarding the specific sites within the renal microcirculation affected by angiotensin II (ANG II). Under some conditions, ANG II can elicit direct vasoconstrictor responses in the preglomerular vessels and efferent arterioles. These experiments were designed to evaluate the binding of {sup 125}I-ANG II in preglomerular vessels. Arcuate and interlobular arteries, with attached proximal segments of afferent arterioles, were microdissected from rabbit renal cortexes. A membrane preparation was obtained from the pooled freshly dissected vessels and utilized in an ANG II radioreceptor assay on the same day. The dissociation of bound ANG II was enhanced in the presence of a nonhydrolyzable analogue of GTP. Linear Scatchard plots were obtained, indicating the presence of a single class of high-affinity binding sites. In conclusion, there is a single class of specific ANG II receptors in preglomerular vessels. The K{sub D} and N are similar, but the binding inhibition potencies of selected ANG analogues differ in renal and extrarenal vascular tissues. Intrarenal vascular receptors also appear to differ from glomerular receptors. Furthermore, these data support the concept that ANG II may affect renal vascular resistance at sites proximal to the distal afferent arterioles.

  9. New concept for the prevention and treatment of metastatic lymph nodes using chemotherapy administered via the lymphatic network

    PubMed Central

    Kodama, Tetsuya; Matsuki, Daisuke; Tada, Asuka; Takeda, Kazu; Mori, Shiro

    2016-01-01

    Intravenous chemotherapy has poor access to metastatic lymph nodes (LNs) and is limited by short-lived drug concentrations. Here, we describe the administration of chemotherapy via the lymphatic network as a new concept for the prevention and treatment of metastatic LNs. A metastatic LN can be treated by the injection of drugs into an upstream LN, either the sentinel LN (SLN) or another upstream LN. In a mouse model, tumor cells were inoculated into the subiliac LN (SiLN) to induce metastasis to the proper axillary LN (PALN). Two routes were used for drug delivery to the PALN, namely from the SiLN and from the accessory axillary LN (AALN). We found that tumor masses were formed in lymphatic vessels between the SiLN and PALN. The flow of fluorescent solution injected into the SiLN towards the PALN decreased with tumor mass formation. Delivery from the AALN (free of metastatic tumor cells) to the PALN was identified as an alternative route. Intranodal injection can deliver high concentrations of drugs to secondary metastatic LNs. The study advocates a new concept for the prevention and treatment of metastatic lymph nodes whereby drugs injected into upstream lymph nodes can reach metastatic lymph nodes via the lymphatic network. PMID:27581921

  10. Intravital Two-Photon Imaging of Lymphocytes Crossing High Endothelial Venules and Cortical Lymphatics in the Inguinal Lymph Node.

    PubMed

    Park, Chung; Hwang, Il-Young; Kehrl, John H

    2016-01-01

    Lymphocyte recirculation through lymph nodes (LNs) requires their crossing of endothelial barriers present in blood vessels and lymphatics by means of chemoattractant-triggered cell migration. The chemoattractant-chemoattractant receptor axes that predominately govern the trafficking of lymphocytes into, and out of, LNs are CCL19/CCR7 and sphingosine 1-phosphate (S1P)/S1P receptor 1 (S1PR1), respectively. Blood-borne lymphocytes downregulate S1PR1 and use CCR7 signaling to adhere to high endothelial venules (HEVs) for transmigration. During their LN residency, recirculating lymphocytes reacquire S1PR1 and attenuate their sensitivity to chemokines. Eventually lymphocytes exit the LN by entering the cortical or medullary lymphatics, a process that depends upon S1PR1 signaling. Upon entering into the lymph, lymphocytes lose their polarity, downregulate their sensitivity to S1P due to the high concentration of S1P, and upregulate their sensitivity to chemokines. However, many of the details of lymphocyte transmigration across endothelial barriers remain poorly understood. Intravital two-photon imaging with advanced microscope technologies not only allows the real-time observation of immune cells in intact LN of a live mouse, but also provides a means to monitor the interactions between circulating lymphocytes and stromal barriers. Here, we describe procedures to visualize lymphocytes engaging and crossing HEVs, and approaching and crossing the cortical lymphatic endothelium to enter the efferent lymph in live mice. PMID:27271904

  11. MMP16 Mediates a Proteolytic Switch to Promote Cell-Cell Adhesion, Collagen Alignment, and Lymphatic Invasion in Melanoma.

    PubMed

    Tatti, Olga; Gucciardo, Erika; Pekkonen, Pirita; Holopainen, Tanja; Louhimo, Riku; Repo, Pauliina; Maliniemi, Pilvi; Lohi, Jouko; Rantanen, Ville; Hautaniemi, Sampsa; Alitalo, Kari; Ranki, Annamari; Ojala, Päivi M; Keski-Oja, Jorma; Lehti, Kaisa

    2015-05-15

    Lymphatic invasion and accumulation of continuous collagen bundles around tumor cells are associated with poor melanoma prognosis, but the underlying mechanisms and molecular determinants have remained unclear. We show here that a copy-number gain or overexpression of the membrane-type matrix metalloproteinase MMP16 (MT3-MMP) is associated with poor clinical outcome, collagen bundle assembly around tumor cell nests, and lymphatic invasion. In cultured WM852 melanoma cells derived from human melanoma metastasis, silencing of MMP16 resulted in cell-surface accumulation of the MMP16 substrate MMP14 (MT1-MMP) as well as L1CAM cell adhesion molecule, identified here as a novel MMP16 substrate. When limiting the activities of these trans-membrane protein substrates toward pericellular collagen degradation, cell junction disassembly, and blood endothelial transmigration, MMP16 supported nodular-type growth of adhesive collagen-surrounded melanoma cell nests, coincidentally steering cell collectives into lymphatic vessels. These results uncover a novel mechanism in melanoma pathogenesis, whereby restricted collagen infiltration and limited mesenchymal invasion are unexpectedly associated with the properties of the most aggressive tumors, revealing MMP16 as a putative indicator of adverse melanoma prognosis. PMID:25808867

  12. New concept for the prevention and treatment of metastatic lymph nodes using chemotherapy administered via the lymphatic network.

    PubMed

    Kodama, Tetsuya; Matsuki, Daisuke; Tada, Asuka; Takeda, Kazu; Mori, Shiro

    2016-01-01

    Intravenous chemotherapy has poor access to metastatic lymph nodes (LNs) and is limited by short-lived drug concentrations. Here, we describe the administration of chemotherapy via the lymphatic network as a new concept for the prevention and treatment of metastatic LNs. A metastatic LN can be treated by the injection of drugs into an upstream LN, either the sentinel LN (SLN) or another upstream LN. In a mouse model, tumor cells were inoculated into the subiliac LN (SiLN) to induce metastasis to the proper axillary LN (PALN). Two routes were used for drug delivery to the PALN, namely from the SiLN and from the accessory axillary LN (AALN). We found that tumor masses were formed in lymphatic vessels between the SiLN and PALN. The flow of fluorescent solution injected into the SiLN towards the PALN decreased with tumor mass formation. Delivery from the AALN (free of metastatic tumor cells) to the PALN was identified as an alternative route. Intranodal injection can deliver high concentrations of drugs to secondary metastatic LNs. The study advocates a new concept for the prevention and treatment of metastatic lymph nodes whereby drugs injected into upstream lymph nodes can reach metastatic lymph nodes via the lymphatic network. PMID:27581921

  13. Subcutaneously Administered Ultrafine PLGA Nanoparticles Containing Doxycycline Hydrochloride Target Lymphatic Filarial Parasites.

    PubMed

    Singh, Yuvraj; Srinivas, Adepu; Gangwar, Mamta; Meher, Jaya Gopal; Misra-Bhattacharya, Shailja; Chourasia, Manish K

    2016-06-01

    Systemic chemotherapeutic targeting of filarial parasites is unfocused due to their deep seated location in lymphatic vessels. This warrants a prolonged dosing regimen in high doses for an anthelmintic like doxycycline hydrochloride (DOX). In order to provide an alternative, we have constructed ultrafine PLGA nanoparticles of DOX (DPNPs), so as to exploit the peculiarity of lymphatic vasculature underneath the subcutaneous layer of skin, which preferentially allows entry of only 10-100 nm sized particles. DPNPs were constructed using a novel solvent diffusion method aided by probe sonication, which resulted in an average size 95.43 ± 0.8 nm as per DLS, PDI 0.168 ± 0.03, zeta potential -7.38 ± 0.32, entrapment efficiency 75.58 ± 1.94%, and refrigerator stability of 7 days with respect to size in the optimized batch. TEM further substantiated the spherical shape of DPNPs along with their actual nonhydrated size as being well below 100 nm. FTIR analysis of DOX, dummy nanoparticles, and freeze-dried DPNPs revealed that the formulation step did not induce prominent changes in the chemical nature of DOX. The drug release was significantly altered (p < 0.05) with 64.6 ± 1.67% release in 48 h from DPNPs and was dictated by Fickian diffusion. Pharmacokinetic studies in Wistar rats further revealed that DPNPs caused a 16-fold prolongation in attainment of plasma Tmax and a 2-fold extension of elimination half-life (28.569 ± 1.27 h) at a dose of 5 mg/kg when compared to native drug (DOX solution) of the same strength. Contrastingly the trend was reversed in regional lymph nodes where Cmax for DPNPs (820 ± 84 ng/mg) was 4-fold greater, and lymphatic Tmax was attained in one-fourth of what was required for DOX solution. This size based preferential lymphatic targeting resulted in significantly greater in vivo antifilarial activity of DPNPs when compared to DOX solution as gauged by several parameters in Brugia malayi infected Mastomys coucha. Interestingly, the

  14. Microbe-dependent lymphatic migration of neutrophils modulates lymphocyte proliferation in lymph nodes

    PubMed Central

    Hampton, Henry R.; Bailey, Jacqueline; Tomura, Michio; Brink, Robert; Chtanova, Tatyana

    2015-01-01

    Neutrophil recruitment to the site of injury is an essential first step of an anti-bacterial response. However, little is known about the basis for and relevance of neutrophil migration from inflamed tissue into lymphoid organs. We established a photoconversion-based system to monitor the fate of neutrophils recruited to inflamed skin. While neutrophils are efficiently recruited to sites of both microbial and sterile lesions, subsequent re-localization to draining lymph nodes happens only when bacteria are present in the primary lesion. Skin egress of neutrophils occurs via lymphatic vessels and is dependent on CD11b and CXCR4 but not CCR7. Neutrophils are the predominant immune cell to migrate from inflamed skin into lymph nodes where they augment lymphocyte proliferation. Furthermore, inhibition of neutrophil migration from skin reduces T-cell proliferation in draining lymph nodes. Thus neutrophils mediate rapid cellular communication between the initial injury site and secondary lymphoid organs and modulate immune responsiveness. PMID:25972253

  15. A study of the topography of the lymphatic system of the Australian brushtail possum (Trichosurus vulpecula).

    PubMed Central

    Jackson, R; Morris, R S

    1996-01-01

    The superficial and deep lymphatic systems of the Australian brushtail possum (Trichosurus vulpecula) are described. In common with other marsupials studied to date and in contrast with most eutherians, there were no popliteal lymph nodes and efferent drainage from the inguinal lymph centre passed directly to the deep axillary group of lymph nodes via an inguinoaxillary trunk. Efferent vessels from the tonsil passed directly to the deep cervical lymph node, which was drained by the tracheal trunk. The mandibular and parotid lymph nodes drained independently to the superficial cervical lymph node. All subcutaneous lymph drainage passed either through the superficial cervical or the axillary lymph centres before entering the venous system, an arrangement which is also found in kangaroos. The significance of the patterns of lesion distributions in possums with naturally occurring tuberculosis caused by Mycobacterium bovis is discussed. PMID:8763477

  16. Differential roles of stretch-sensitive pelvic nerve afferents innervating mouse distal colon and rectum

    PubMed Central

    Brumovsky, Pablo R.; Gebhart, Gerald F.

    2010-01-01

    Information about colorectal distension (i.e., colorectal dilation by increased intraluminal pressure) is primarily encoded by stretch-sensitive colorectal afferents in the pelvic nerve (PN). Despite anatomic differences between rectum and distal colon, little is known about the functional roles of colonic vs. rectal afferents in the PN pathway or the quantitative nature of mechanosensory encoding. We utilized an in vitro mouse colorectum-PN preparation to investigate pressure-encoding characteristics of colorectal afferents. The colorectum with PN attached was dissected, opened longitudinally, and pinned flat in a Sylgard-lined chamber. Action potentials of afferent fibers evoked by circumferential stretch (servo-controlled force actuator) were recorded from the PN. Stretch-sensitive fibers were categorized into the following four groups: colonic muscular, colonic muscular/mucosal, rectal muscular, and rectal muscular/mucosal. Seventy-nine stretch-sensitive PN afferents evenly distributed into the above four groups were studied. Rectal muscular afferents had significantly greater stretch-responses than the other three groups. Virtually all rectal afferents (98%) had low thresholds for response and encoded stimulus intensity into the noxious range without obvious saturation. Most colonic afferents (72%) also had low thresholds (<14 mmHg), but a significant proportion (28%) had high thresholds (>18 mmHg) for response. These high-threshold colonic afferents were sensitized to stretch by inflammatory soup; response threshold was significantly reduced (from 23 to 12 mmHg), and response magnitude significantly increased. These results suggest that the encoding of mechanosensory information differs between colonic and rectal stretch-sensitive PN afferents. Rectal afferents have a wide response range to stretch, whereas high-threshold colonic afferents likely contribute to visceral nociception. PMID:20075141

  17. Effects of intratympanic gentamicin on vestibular afferents and hair cells in the chinchilla.

    PubMed

    Hirvonen, Timo P; Minor, Lloyd B; Hullar, Timothy E; Carey, John P

    2005-02-01

    Gentamicin is toxic to vestibular hair cells, but its effects on vestibular afferents have not been defined. We treated anesthetized chinchillas with one injection of gentamicin (26.7 mg/ml) into the middle ear and made extracellular recordings from afferents after 5-25 (early) or 90-115 days (late). The relative proportions of regular, intermediate, and irregular afferents did not change after treatment. The spontaneous firing rate of regular afferents was lower (P < 0.001) on the treated side (early: 44.3 +/- 16.3; late: 33.9 +/- 13.2 spikes x s(-1)) than on the untreated side (54.9 +/- 16.8 spikes x s(-1)). Spontaneous rates of irregular and intermediate afferents did not change. The majority of treated afferents did not measurably respond to tilt or rotation (82% in the early group, 76% in the late group). Those that did respond had abnormally low sensitivities (P < 0.001). Treated canal units that responded to rotation had mean sensitivities only 5-7% of the values for untreated canal afferents. Treated otolith afferents had mean sensitivities 23-28% of the values for untreated otolith units. Sensitivity to externally applied galvanic currents was unaffected for all afferents. Intratympanic gentamicin treatment reduced the histological density of all hair cells by 57% (P = 0.04). The density of hair cells with calyx endings was reduced by 99% (P = 0.03), although some remaining hair cells had other features suggestive of type I morphology. Type II hair cell density was not significantly reduced. These findings suggest that a single intratympanic gentamicin injection causes partial damage and loss of vestibular hair cells, particularly type I hair cells or their calyceal afferent endings, does not damage the afferent spike initiation zones, and preserves enough hair cell synaptic activity to drive the spontaneous activity of vestibular afferents.

  18. Differential roles of stretch-sensitive pelvic nerve afferents innervating mouse distal colon and rectum.

    PubMed

    Feng, Bin; Brumovsky, Pablo R; Gebhart, Gerald F

    2010-03-01

    Information about colorectal distension (i.e., colorectal dilation by increased intraluminal pressure) is primarily encoded by stretch-sensitive colorectal afferents in the pelvic nerve (PN). Despite anatomic differences between rectum and distal colon, little is known about the functional roles of colonic vs. rectal afferents in the PN pathway or the quantitative nature of mechanosensory encoding. We utilized an in vitro mouse colorectum-PN preparation to investigate pressure-encoding characteristics of colorectal afferents. The colorectum with PN attached was dissected, opened longitudinally, and pinned flat in a Sylgard-lined chamber. Action potentials of afferent fibers evoked by circumferential stretch (servo-controlled force actuator) were recorded from the PN. Stretch-sensitive fibers were categorized into the following four groups: colonic muscular, colonic muscular/mucosal, rectal muscular, and rectal muscular/mucosal. Seventy-nine stretch-sensitive PN afferents evenly distributed into the above four groups were studied. Rectal muscular afferents had significantly greater stretch-responses than the other three groups. Virtually all rectal afferents (98%) had low thresholds for response and encoded stimulus intensity into the noxious range without obvious saturation. Most colonic afferents (72%) also had low thresholds (<14 mmHg), but a significant proportion (28%) had high thresholds (>18 mmHg) for response. These high-threshold colonic afferents were sensitized to stretch by inflammatory soup; response threshold was significantly reduced (from 23 to 12 mmHg), and response magnitude significantly increased. These results suggest that the encoding of mechanosensory information differs between colonic and rectal stretch-sensitive PN afferents. Rectal afferents have a wide response range to stretch, whereas high-threshold colonic afferents likely contribute to visceral nociception.

  19. Vascular, glial, and lymphatic immune gateways of the central nervous system.

    PubMed

    Engelhardt, Britta; Carare, Roxana O; Bechmann, Ingo; Flügel, Alexander; Laman, Jon D; Weller, Roy O

    2016-09-01

    Immune privilege of the central nervous system (CNS) has been ascribed to the presence of a blood-brain barrier and the lack of lymphatic vessels within the CNS parenchyma. However, immune reactions occur within the CNS and it is clear that the CNS has a unique relationship with the immune system. Recent developments in high-resolution imaging techniques have prompted a reassessment of the relationships between the CNS and the immune system. This review will take these developments into account in describing our present understanding of the anatomical connections of the CNS fluid drainage pathways towards regional lymph nodes and our current concept of immune cell trafficking into the CNS during immunosurveillance and neuroinflammation. Cerebrospinal fluid (CSF) and interstitial fluid are the two major components that drain from the CNS to regional lymph nodes. CSF drains via lymphatic vessels and appears to carry antigen-presenting cells. Interstitial fluid from the CNS parenchyma, on the other hand, drains to lymph nodes via narrow and restricted basement membrane pathways within the walls of cerebral capillaries and arteries that do not allow traffic of antigen-presenting cells. Lymphocytes targeting the CNS enter by a two-step process entailing receptor-mediated crossing of vascular endothelium and enzyme-mediated penetration of the glia limitans that covers the CNS. The contribut