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Background: The lymphatic system is essential for maintaining the balance of interstitial fluid in tissues and for returning protein-rich fluids (lymph) to the bloodstream. Congenital lymphatic defects lead to accumulation of lymph in peripheral tissues and body cavities, termed primary lymphedema. To date, only a limited number of individual genes have been identified in association with primary lymphedema. However, variability of age of onset and severity of lymphatic abnormalities within some families suggests that multiple mutations or genes may be responsible, thus hampering efforts to identify individual associated genes., Methods: Whole exome sequencing (WES) was performed in 4 members of a large multigeneration family with highly variable lymphedema and followed by Sanger sequencing for identified mutations in 34 additional family members. Genotypes were correlated with clinical and lymphangioscintigraphic phenotypes., Results: WES uncovered 2 different mechanotransducer PIEZO1 mutations and one FOXC2 transcription factor mutation in various combinations. Sanger sequencing confirmed the presence/absence of the 3 variants in affected and unaffected family members and co-segregation of one or more variants with disease. Genetic profiles did not clearly correlate with the highly variable severity of lymphatic abnormalities., Conclusions: WES in lymphedema families can uncover unexpected combinations of several lymphedema-associated mutations. These findings provide essential information for genetic counseling and reveal complex gene interactions in lymphatic developmental pathways. These can offer insights into the complex spectrum of clinical and lymphatic lymphedema phenotypes and potential targets for treatment., (Copyright © 2021 Elsevier Inc. All rights reserved.)

Connexin proteins form gap junctions controlling exchange of ions and small molecules between cells and play an important role in movement of lymph within lymphatic vessels. Connexin47 (CX47) is highly expressed in lymphatic endothelial cells and CX47 missense mutations, i.e., R260C, cosegregate with primary lymphedema in humans. However, studies utilizing CX47 knockout mice have failed to demonstrate any lymphatic anomalies. To unravel the lymphatic consequences of expressing a mutant CX47 protein, we used CRISPR technology to create a mouse carrying a Cx47 missense mutation (Cx47R259C) equivalent to the human CX47R260C missense mutation associated with human primary lymphedema. Intradermal Evans Blue dye injection identified a 2-fold increase in regional lymph nodes in homozygous Cx47R259C mice compared to wildtype, particularly in the jugular region (4.8 ± 0.4 and 2.0 ± 0.0, respectively, p<0.01). Associated lymphatic channels were increased in Cx47R259C mice and mesenteric lymph reflux occurred in homozygous Cx47R259C mice but not in wildtype. Contractility of superficial cervical lymphatics, assessed by pressure myography, was reduced in homozygous Cx47R259C mice compared to wildtype. In conclusion, our data are the first to demonstrate a role for the Cx47 protein in lymphatic anatomy and function. This phenotype is similar to that found with other valve deficient mouse mutants, e.g., in Foxc2. Of significance, this study is the first to use CRISPR technology to develop a pre-clinical model of primary lymphedema and demonstrates the importance of distinguishing between lack of and presence of mutant protein when developing clinically relevant animal models for translation of pre-clinical findings., Competing Interests: The authors of this article and the planning committee members and staff have no relevant financial relationships with commercial interests to disclose., (Copyright by International Society of Lymphology.)

A second multigeneration family with hereditary lymphedema (LE) secondary to a variant in the planar polarity gene, CELSR1, is described. Dominant inheritance of the variant was discovered using whole-exome sequencing and confirmed by Sanger sequencing. In contrast to heterozygous males, all heterozygous females showed LE during physical examination albeit variable in severity and age of onset. Lymphscintigraphy in affected females showed previously undescribed lymphatic abnormalities consistent with lymphangiectasia, valve dysfunction, and thoracic duct reflux., (© 2019 John Wiley & Sons A/S. Published by John Wiley & Sons Ltd.)

Context: Historically, administration and dosing of antivenom (AV) have been guided primarily by physician judgment because of incomplete understanding of the envenomation process. As demonstrated previously, lymphatic absorption plays a major role in the availability and pharmacokinetics (PK) of coral snake venom injected subcutaneously, which suggests that absorption from subcutaneous tissue is the limiting step for venom bioavailability, supporting the notion that the bite site is an ongoing venom depot. This feature may underlie the recurrence phenomena reported in viperid envenomation that appear to result from a mismatch between venom and AV PK. The role of lymphatic absorption in neutralization of venom by AV administered intravenously remains unclear. Methods: The effect of AV on systemic bioavailability and neutralization of Micrurus fulvius venom was assessed using a central lymph-cannulated sheep model. Venom was administered by subcutaneous injection in eight sheep, four with and four without thoracic duct cannulation and drainage. Two hours after venom injection, AV was administered intravenously. Venom and AV concentrations in serum and lymph were determined by ELISA assay from samples collected over a 6-h period and in tissues harvested post-mortem. Results: After AV injection, venom levels in serum fell immediately to undetectable with a subsequent increase in concentration attributable to non-toxic venom proteins. In lymph, AV became detectable 6 min after treatment; venom levels dropped concurrently but remained detectable 4 h later. Post-mortem samples from the venom injection site confirmed the presence of venom near the point of injection. Neither venom nor AV was detected at significant concentrations in major organs or contralateral skin. Conclusions: Intravenous AV immediately neutralizes venom in the bloodstream and can extravasate to neutralize venom absorbed by lymph but this neutralization seems to be slow and incomplete. Residual venom in the inoculation site demonstrates that this site functions as a depot where it is not neutralized by AV, which allows the venom to remain active with slow delivery to the bloodstream for ongoing systemic distribution.

The number of patients surviving repair of complex congenital heart disease (CCHD) has increased due to improved surgical techniques, post operative management and outpatient care. Likewise, this growing patient population has demonstrated an increasing number and complexity of complications involving the lymphatic system. To evaluate the peripheral and central lymphatic system, whole-body lymphangioscintigraphy (LAS) is considered as the initial imaging evaluation of choice. To date, very few publications exist on the value of lymphatic imaging techniques in infants and small children with lymphatic complications following surgery for congenital heart disease. A retrospective review of medical records from 2008 to 2018 was performed for pediatric patients referred for lymphatic complications after CCHD surgery at an academic medical center. LAS and SPECT/CT was performed using intradermal bipedal injections of Tc 99m labeled filtered sulfur colloid, and in some patients also bilateral hand injections, followed by dynamic imaging and whole- body planar imaging typically up to 180 minutes post injection. Clinical decision making and outcomes were recorded. LAS and SPECT/CT were performed without complication in pediatric patients with prior surgery for CCHD. LAS successfully localized various lymphatic abnormalities such as lymphatic obstruction, reflux, and leaks, which were further delineated by SPECT/CT. LAS findings directed further evaluation with more definitive studies, management and prognosis. Five of the ten patients had follow up outcome data - 2 years and up to 10 years. LAS and SPECT/CT are safe and effective techniques for the initial evaluation of lymphatic abnormalities in pediatric patients with CCHD. LAS, particularly with further 3D localization by SPECT/CT, provides functional imaging of peripheral and central lymphatic flow and thus provides guidance for medical therapy, non operative interventional management, and surgical therapy for these diverse, debilitating, and often life threatening disorders., Competing Interests: The authors of this article and the planning committee members and staff have no relevant financial relationships with commercial interests to disclose., (Copyright by International Society of Lymphology.)

Introduction: Despite being one of the most common neurological diseases, it is unknown whether there may be a genetic basis to temporal lobe epilepsy (TLE). Whole genome analyses were performed to test the hypothesis that temporal cortical gene expression differs between TLE patients with high vs. low baseline seizure frequency., Methods: Baseline seizure frequency was used as a clinical measure of epileptogenicity. Twenty-four patients in high or low seizure frequency groups (median seizures/month) underwent anterior temporal lobectomy with amygdalohippocampectomy for intractable TLE. RNA was isolated from the lateral temporal cortex and submitted for expression analysis. Genes significantly associated with baseline seizure frequency on likelihood ratio test were identified based on >0.90 area under the ROC curve, P value of <0.05., Results: Expression levels of forty genes were significantly associated with baseline seizure frequency. Of the seven most significant, four have been linked to other neurologic diseases. Expression levels associated with high seizure frequency included low expression of Homeobox A10, Forkhead box A2, Lymphoblastic leukemia derived sequence 1, HGF activator, Kelch repeat and BTB (POZ) domain containing 11, Thanatos-associated protein domain containing 8 and Heparin sulfate (glucosamine) 3-O-sulfotransferase 3A1., Conclusions: This study describes novel associations between forty known genes and a clinical marker of epileptogenicity, baseline seizure frequency. Four of the seven discussed have been previously related to other neurologic diseases. Future investigation of these genes could establish new biomarkers for predicting epileptogenicity, and could have significant implications for diagnosis and management of temporal lobe epilepsy, as well as epilepsy pathogenesis., (Copyright © 2016. Published by Elsevier B.V.)

Objective: We sought to test the hypothesis that turmeric-derived curcuminoids limit reperfusion brain injury in an experimental model of stroke via blockade of early microvascular inflammation during reperfusion., Methods: Male Sprague Dawley rats subjected to MCAO/R were treated with turmeric-derived curcuminoids (vs. vehicle) 1 hour prior to reperfusion (300 mg/kg ip). Neutrophil adhesion to the cerebral microcirculation and measures of neutrophil and endothelial activation were assayed during early reperfusion (0-4 hours); cerebral infarct size, edema, and neurological function were assessed at 24 hours. Curcuminoid effects on TNFα-stimulated human brain microvascular endothelial cell (HBMVEC) were assessed., Results: Early during reperfusion following MCAO, curcuminoid treatment decreased neutrophil rolling and adhesion to the cerebrovascular endothelium by 76% and 67% and prevented >50% of the fall in shear rate. The increased number and activation state (CD11b and ROS) of neutrophils were unchanged by curcuminoid treatment, while increased cerebral expression of TNFα and ICAM-1, a marker of endothelial activation, were blocked by >30%. Curcuminoids inhibited NF-κB activation and subsequent ICAM-1 gene expression in HBMVEC., Conclusion: Turmeric-derived curcuminoids limit reperfusion injury in stroke by preventing neutrophil adhesion to the cerebrovascular microcirculation and improving shear rate by targeting the endothelium., (© 2013 John Wiley & Sons Ltd.)

The contribution of the lymphatic system to the absorption and systemic bioavailability of Micrurus fulvius venom after subcutaneous (SC) administration was assessed using a central lymph-cannulated sheep model. Micrurus fulvius venom was administered either by intravenous bolus (IV) or subcutaneous injection (SC) in 12 sheep with and without thoracic duct cannulation and drainage. Venom concentration in serum and lymph was determined by a sandwich enzyme-linked immunosorbent assay (ELISA) in samples collected over a 6-hour period and in tissues harvested at the end of the experiment. Pharmacokinetic parameters were determined by a non-compartmental analysis. In the lymphatic cannulated group, over the 6 hours after the venom was administered, 69% of administered dose was accounted for in blood (45%) and lymph (25%). Negligible levels of venom were detected in organs and urine implying that the steady state observed after SC administration is maintained by a slow absorption process. Comparison of kinetics of the thoracic duct cannulated and non-cannulated groups showed that lymphatic absorption contributed in an important way to maintenance of this steady state. These results show that the limiting process in the pharmacokinetics of Micrurus fulvius venom following SC administration is absorption, and that the lymphatic system plays a key role in this process.

Dysmorphogenesis of lymph nodes displayed in a fork head transcription factor Foxc2 haploinsufficient mice--a model for lymphedema-distichiasis syndrome--was studied by immunohistochemistry and electron microscopy. The Foxc2 heterozygous mice manifested lymph node hyperplasia composed of conspicuous proliferation of endothelial cells forming the lymphatic sinus and α-smooth muscle actin (SMA)-immunopositive fibroblast-like cells in the lymphatic pulp, particularly around the sinus. The hyperplastic sinus endothelial cells and the SMA-positive cells demonstrated distinct immunolocalization of platelet-derived growth factor (PDGF)-B, a crucial chemoattractant for vascular mural cell recruitment, and its receptor, PDGFR-β, respectively. The observations suggest that the sinus endothelial cells elicit abnormal recruitment of the fibroblast-like cells as a type of vascular mural cells via PDGF-B/PDGFR-β signaling in lymph nodes of the Foxc2 heterozygotes. Furthermore, in Foxc2 heterozygous lymph nodes, recruited SMA-positive cells displayed an intense immunoreaction for vascular endothelial growth factor (VEGF)-C, a highly specific lymphangiogenic factor, and its receptor, VEGFR-3, was preferentially distributed in the lymphatic sinus endothelial cells. These findings suggest that an interactive cycle between lymphatic sinus endothelial cells and the fibroblast-like cells, which involves PDGF-B/PDGFR-β and VEGF-C/VEGFR-3 signaling, is essential for aberrant hyperplasia of the lymphatic sinus and the fibroblast-like cells in Foxc2 haploinsufficiency.

We describe a method for generating primary cultures of human brain microvascular endothelial cells (HBMVECs). HBMVECs are derived from microvessels isolated from temporal tissue removed during operative treatment of epilepsy. The tissue is mechanically fragmented and size filtered using polyester meshes. The resulting microvessel fragments are placed onto type I collagen-coated flasks to allow HBMVECs to migrate and proliferate. The overall process takes less than 3 h and does not require specialized equipment or enzymatic processes. HBMVECs are typically cultured for approximately 1 month until confluent. Cultures are highly pure ( approximately 97% endothelial cells; approximately 3% pericytes), are reproducible, and show characteristic brain endothelial markers (von Willebrand factor, glucose transporter-1) and robust expression of tight and adherens junction proteins as well as caveolin-1 and efflux protein P-glycoprotein. Monolayers of HBMVECs show characteristically high transendothelial electric resistance and have proven useful in multiple functional studies for in vitro modeling of the human blood-brain barrier.

Lymphedema or tissue swelling from impaired lymph drainage commonly occurs after regional nodal dissection and/or radiation therapy for cancer control. Treatment options for this disabling and life-altering complication involve long-term labor-intensive commitments. Sentinel node biopsy can forestall removal of negative regional nodes, offering some protection against lymphedema, however, most preventive measures are elusive, ineffective, or unproven. Our goal was to determine whether the radioprotectant amifostine could prevent or retard the development of lymphedema in a rodent radiation therapy-dependent model yet not offer tumor protection from the therapeutic effects of radiation therapy. We pre-treated rats after unilateral radical groin dissection with the organic thiophosphate radioprotectant amifostine or placebo prior to single dose post-operative groin radiation therapy and monitored hindlimb volumes, wound scores, and tissue lymphostasis. In addition, we determined whether amifostine protected human MCF7 breast cancer cells exposed to a range of radiation therapy doses in an in vitro clonogenic assay and an in vivo MCF7 tumor xenograft model. Our findings indicate that amifostine markedly reduced the volume of limb lymphedema and dramatically improved wound healing and tissue lymphostasis in the rodent lymphedema model. The in vivo and in vitro studies further demonstrated that amifostine offered no MCF7 tumor protection from radiation therapy. These pre-clinical findings provide proof-of-principle to further delineate specific mechanisms underlying amifostine's beneficial effects, determine optimal amifostine-radiation therapy dosing regimens, and thereby expedite translation into clinical trials to reduce lymphedema incidence and severity in cancer patients at high lymphedema risk in whom radiation therapy is the recommended therapy.

Lymphedema-distichiasis (OMIM 153400) is a dominantly inherited disorder typically presenting with lymphedema at puberty and distichiasis at birth. The condition has been decisively linked to mutations in the forkhead transcription factor FOXC2 which have been primarily frameshift mutations truncating the protein. We report here a novel missense mutation along with a literature review summarizing reported mutations.

Recent advances in molecular lymphology and lymphatic phenotyping techniques in small animals offer new opportunities to delineate mutant mouse models. Chy-3 mutant mice were originally named for their chylous ascites, but the underlying lymphatic disorder was not defined. We now re-examined these mice and applied advanced genotyping and lymphatic phenotyping techniques to pinpoint the specific lymphatic defect in this mouse model. We demonstrated that Chy-3 mice carry a large chromosomal deletion that includes Vegfc and narrowed this region by monitoring the heterozygosity of genetic markers. We found that Chy-3 mice not only exhibited chylous ascites but also lymphedema of the hind paws and, in approximately half of the males, lymphedema of the penis. Visual lymphangiography and immunofluorescence staining showed a hypoplastic dermal lymphatic network, whereas the blood vasculature appeared unaffected. This hypoplastic lymphatic network was functional, and all adult Chy-3 mice exhibited a lateral lymphatic pathway directly connecting the inguinal to the axillary lymph node. The dermal superficial to deep lymphatic connections in upper limbs and in all cervical regions were intact and functionally drained the upper body. Lymphatic tracer was not transported from the dermal to the deep truncal lymphatic system in the lower limbs, even though the deep lymphatic vessels and nodes were present and patent. These findings further delineate the lymphatic phenotype of Chy-3 mice, identify a collateral lymph drainage pathway previously undescribed in other genetic models of lymphedema, and demonstrate a predilection for lymphatic abnormalities of the lower limbs., ((c) 2007 Wiley-Liss, Inc.)

The fine structure of lymphatic capillaries in the digestive organs of angiopoietin-2 (Ang2) knockout mice was studied by using both immunohistochemistry and electron microscopy. The genetic deletion of Ang2 yielded hypoplasia and disorganization of the lymphatic capillaries, with their shapes being irregular, and an aberrant recruitment of vascular periendothelial cells immunopositive for smooth muscle actin to the lymphatic capillaries. The abnormal lymphatic periendothelial cells were considered to be a type of pericyte for the lymphatic capillaries after the deletion of Ang2, because they were ultrastructurally characterized by abundant thin myofilaments in their cytoplasm and long cytoplasmic extensions similar to those shown by blood vascular pericytes. The genetic replacement of Ang2 with Ang1 rescued the defects, viz., the disorganization and disordered structure of the lymphatic capillaries. The present findings suggest that Ang2 serves the morphogenesis of lymphatic capillaries as an agonist for the receptor, Tie2, and that Ang1 can replace Ang2 in guiding lymphatic formation and development.

Lymphedema-distichiasis (LD) (OMIM 153400) is a rare autosomal-dominant condition characterized by pubertal onset of lower limb lymphedema and an aberrant second row of eyelashes arising from the meibomian glands. In some patients cardiac, skeletal and other defects coexist. We previously identified inactivating, nonsense and frameshift mutations in the forkhead transcription factor FOXC2 in affected members of LD families. To further delineate the relationship of FOXC2 deficiency to the clinical (and lymphangiodysplastic) phenotype in this syndrome, we performed dynamic lymphatic imaging and immunohistochemical examination of lymphatic tissues in mice heterozygous (+/-) for a targeted disruption of Foxc2. Adult heterozygote mice characteristically exhibited a generalized lymphatic vessel and lymph node hyper plasia and rarely exhibited hindlimb swelling. Retrograde lymph flow through apparently incompetent interlymphangion valves into the mesenteric nodes, intestinal wall and liver was also observed. In addition, Foxc2 +/- mice uniformly displayed distichiasis. We conclude that Foxc2 haploinsufficient mice mimic closely the distinctive lymphatic and ocular phenotype of LD patients. Furthermore, the craniofacial, cardiovascular and skeletal abnormalities sometimes associated with LD have previously been shown to be fully penetrant in homozygous Foxc2 null mice. This Foxc2 mutant mouse thus provides an ideal model for exploring molecular mechanisms and physiologic events in mesenchymal differentiation associated with lymphatic growth and development and the clinical abnormalities seen in human LD syndrome.

The lymph vascular system parallels the blood vasculature and as one of its key functions returns liquid and solutes to the bloodstream, including macromolecules that have escaped from blood capillaries and entered the interstitium. In conjunction with interspersed lymph nodes and lymphoid organs, the lymphatic vasculature also acts as a conduit for trafficking immune cell populations. Echoing the explosion of knowledge about blood vessel angiogenesis (properly termed "hemangiogenesis"), the past two decades have also witnessed a series of significant, yet less-noticed discoveries bearing on "lymphangiogenesis," along with delineation of the spectrum of lymphedema-angiodysplasia syndromes. Failure of lymph transport promotes a brawny proteinaceous edema of the affected limb, organ, or serous space that is disfiguring, disabling, and on occasion even life-threatening. Key members of the vascular endothelial growth factor (VEGF) and angiopoietin families of vascular growth factors (and their corresponding tyrosine kinase endothelial receptors) have been identified which preferentially influence lymphatic growth and, when manipulated in genetically engineered murine models, produce aberrant "lymphatic phenotypes." Moreover, mutations in VEGF receptor and forkhead family developmental genes have now been linked and implicated in the pathogenesis of two familial lymphedema-angiodysplasia syndromes. Thus, recent advances in "molecular lymphology" are elucidating the poorly understood development, physiology, and pathophysiology of the neglected lymphatic vasculature. In combination with fresh insights and refined tools in "clinical lymphology," these advances should lead not only to earlier detection and more rational classification of lymphatic disease but also to better therapeutic approaches, including designer drugs for lymphangiostimulation and lymphangioinhibition and gene therapy to modulate lymphatic growth., (Copyright 2001 Wiley-Liss, Inc.)

We previously described six families with Milroy congenital lymphedema, only one of which showed possible linkage to a candidate locus on chromosome 5 [Witte et al., 1998]. We have now performed a complex segregation analysis of these families, and performed linkage analyses with the other 387 markers used in our genome-wide search. Our results confirm that Milroy lymphedema is generally inherited as a dominant condition. However, this mode of inheritance, as elucidated from the segregation analyses, did not account for all observed familial correlations. The segregation analysis also suggested that shared environmental or additional genetic factors are important in explaining the observed familial aggregation. The finding of linkage to multiple locations in the largest family studied by multipoint parametric mapping (one of which was confirmed by sib-pair non-parametric mapping), suggests that Milroy congenital lymphedema may be oligogenic in this family., (Copyright 2001 Wiley-Liss, Inc.)

Conventional oil-contrast lymphography has long been the mainstay for lymphatic imaging. However, the emergence of computed tomography (CT) and magnetic resonance (MR) imaging has severely curtailed its use. Because of recent improvements and refinements, lymphangioscintigraphy now permits high-resolution imaging of peripheral lymphatic vessels and provides insight into lymph flow dynamics. It is indispensable for patients with known or suspected lymphatic circulatory disorders in confirming the diagnosis and delineating the pathogenesis and evolution of lymphedema. In addition, lymphangioscintigraphy helps evaluate lymphatic truncal anatomy and radiotracer transport. It can also be used to evaluate the efficacy of various treatment options designed to facilitate lymph flow or reduce lymph formation. The procedure is essentially noninvasive, can easily be repeated, and does not adversely affect the lymphatic vascular endothelium. MR imaging complements lymphangioscintigraphy in the monitoring and treatment of more complex lymphatic circulatory disorders, whereas CT facilitates catheter-guided percutaneous sclerosis or obliteration of specific lymphangiectasia or lymphangioma syndromes. Ultrasonography has proved useful in the setting of filariasis. Patients with a provisional diagnosis of peripheral lymphatic dysfunction or idiopathic edema should undergo diagnostic lymphangioscintigraphy and, in some cases, MR imaging to verify diagnostic accuracy, pinpoint the specific abnormality, and help guide subsequent therapy.

Analogies are drawn between important unknowns in AIDS and alcohol research, related to underlying common pathogenetic mechanisms, immunodysregulation, cofactors, and prominent vascular manifestations. The central role of the blood and lymphatic vasculatures and specifically their endothelial lining in many facets of the immune response is reviewed. Evidence is presented that both alcohol and HIV (as well as other coinfecting viruses in AIDS) target and alter endothelial cells and the angiogenic process. These concepts are further illustrated by a serendipitous viral epidemic among rats on continuous long-term alcoholic and control nonalcoholic diets, where synergism between alcohol and virus appeared to underlie multiple vascular proliferative lesions in the liver. In AIDS and alcoholism/alcoholic liver disease (ALD), the prominent features of dysregulated angiogenesis point to the endothelium as a key player in pathogenesis of these seemingly disparate disorders and potentially in immunomodulation.

The nature of Kaposi sarcoma (KS) (vascular malignancy vs. discordant angiogenesis) and lineage of the progenitor cell remain unclear. Therefore, AIDS-KS enzyme isolate cultures were prepared from excised skin lesions. Endothelial marker positivity for Factor VIII related antigen (F8RAg), Ulex europaeus agglutinin (UEA), and angiotensin-converting enzyme (ACE) were determined by fluorescence microscopy (FM) and flow cytometry (FCM). DNA cell-cycle analysis was performed using FCM. KS lesions showed large thick-walled channels (F8RAg and UEA strongly +), narrow vascular slits and thin-walled lakes (F8RAg and UEA weakly +), and non-prominent spindle cells (F8RAg and UEA almost uniformly negative). KS cultures yielded heterogenous populations of spindle, stellate, and flattened endothelial-like cells, displaying positivity for F8RAg (64 +/- 3%; mean +/- SE), UEA (40 +/- 9%), and ACE (81 +/- 9%). When injected subcutaneously in the nude mouse these cells failed to produce tumors. During contact inhibition induced quiescence, KS cultures exhibited a high G2M (18 +/- 3%) compared to non-KS (7 +/- 4%; p < 0.04), evidence of an altered proliferative potential consistent with a transdifferentiated or transformed phenotype.

According to the "intact cell hypothesis," ethanol (EtOH) primarily targets nonparenchymal hepatic sinusoidal and perisinusoidal cells, thereby promoting sinusoidal capillarization, which impairs microcirculatory exchange of nutrients and wastes, promotes tissue fibrosis, and only indirectly damages hepatic parenchyma. To test this hypothesis, sinusoidal ultrastructure and hepatic lymph flow and protein composition were examined in rats up to 16 weeks after intragastric EtOH (36% calories)-high fat infusion (Tsukamoto-French model) (TF). The findings were compared to dietary controls and interpreted in light of restricted transsinusoidal protein movement observed in patients with alcoholic cirrhosis. In vitro, alterations in rat hepatic sinusoidal endothelial cell (RSE) morphology, proliferative index, and transendothelial macromolecular permeability (Evans blue-albumin uptake into microcarrier beads) were determined after acute and more chronic exposure to 0.1%-5 vol% EtOH. TF displayed 75% increased liver size, perisinusoidal collagenosis, and basal lamina deposition, ascitic fluid, and doubling of hepatic lymph liquid and protein flux. In vitro, 1% EtOH retracted RSE cell margins, enhanced transendothelial Evans blue-albumin flux and suppressed proliferative index. Thus, high EtOH concentration, clinically attainable in the portal blood during an alcoholic binge, both in vivo and in vitro, promotes early structural and functional alterations in sinusoidal endothelium, which over time may be responsible for progressive restriction of free intrahepatic exchange of liquid, macromolecules, and migrating immune cells.

Rationale and Objectives: To evaluate acquired lymphatic abnormalities caused by filariasis, the authors examined the peripheral lymphatic system in normal ferrets and those chronically infected with Brugia malayi using magnetic resonance imaging (MRI). The findings were compared with previously obtained lymphangioscintigraphic (LAS) images in ferrets both with and without experimental filariasis., Methods: Fifteen ferrets (11 infected with B. malayi and four noninfected controls) underwent whole body coronal MRI using a quadrature transmission-receive head coil at 0.5 Tesla operating at a resonant frequency of 21.5 mHz for protons with a 25-cm field of view., Results: In contrast to normal animals, infected ferrets showed dilated hindlimb dermal lymphatic collaterals, enlarged high-signal intensity groin lymph nodes with punctate low-signal intensity centers and separate low-signal intensity spots with irregular thin channels, suggestive of nests of viable adult nematodes within tortuous lymphatics and nodes. MRI correlated with the LAS findings, and the interpretations were supported by light, scanning electron, and video microscopy., Conclusions: T2-weighted MRI in conjunction with LAS accurately depicts the peripheral lymphatic system in filarial-infected ferrets. These two modalities are useful complementary techniques to examine disorders characterized by lymphatic insufficiency.