Lymph node metastases in cancer patients are associated with tumor aggressiveness, poorer prognoses, and the recommendation for systemic therapy. Whether cancer cells in lymph nodes can seed distant ...metastases has been a subject of considerable debate. We studied mice implanted with cancer cells (mammary carcinoma, squamous cell carcinoma, or melanoma) expressing the photoconvertible protein Dendra2. This technology allowed us to selectively photoconvert metastatic cells in the lymph node and trace their fate. We found that a fraction of these cells invaded lymph node blood vessels, entered the blood circulation, and colonized the lung. Thus, in mouse models, lymph node metastases can be a source of cancer cells for distant metastases. Whether this mode of dissemination occurs in cancer patients remains to be determined.
Key points
Previously, it was found that the popliteal lymph node (PLN) enlarges during the pre‐arthritic ‘expanding’ phase, and then ‘collapses’ with adjacent knee flare and is associated with the ...loss of the intrinsic lymphatic pulse.
However, the mechanisms responsible are unknown and we therefore developed in vivo methods to measure lymph viscosity, lymphatic pumping pressure (LPP) in the lymphatic vessels afferent to the PLN, and lymph node pressure (LNP).
Multiphoton fluorescence recovery after photobleaching (MP‐FRAP) was used to calculate lymph viscosity and speed; no difference was found among mice with wild‐type (WT), expanding or collapsed PLN in lymph viscosity, but lymph speed was found to be decreased in mice with collapsed PLN compared to WT and expanding PLN mice.
LPP was measured indirectly by slowly releasing a pressurized cuff occluding ICG fluorescent dye; we found that mice with expanding PLN exhibit a higher LPP compared to WT and mice with collapsed PLN show an extremely low LPP.
Direct measurement of LNP demonstrated a decrease in expanding PLN versus WT pressure, which dramatically increased in collapsed PLN.
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 rheumatoid arthritis progression and possibly other chronic inflammatory conditions
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.
Rheumatoid arthritis is a chronic inflammatory disease manifested by episodic flares in affected joints that are challenging to predict and treat. Longitudinal contrast enhanced-MRI (CE-MRI) of ...inflammatory arthritis in tumor necrosis factor-transgenic (TNF-Tg) mice has demonstrated that popliteal lymph nodes (PLN) increase in volume and contrast enhancement during the pre-arthritic "expanding" phase of the disease, and then suddenly "collapse" during knee flare. Given the potential of this biomarker of arthritic flare, we aimed to develop a more cost-effective means of phenotyping PLN using ultrasound (US) imaging. Initially we attempted to recapitulate CE-MRI of PLN with subcutaneous footpad injection of US microbubbles (DEFINITY®). While this approach allowed for phenotyping via quantification of lymphatic sinuses in PLN, which showed a dramatic decrease in collapsed PLN versus expanding or wild-type (WT) PLN, electron microscopy demonstrated that DEFINITY® injection also resulted in destruction of the lymphatic vessels afferent to the PLN. In contrast, Power Doppler (PD) US is innocuous to and efficiently quantifies blood flow within PLN of WT and TNF-Tg mice. PD-US demonstrated that expanding PLN have a significantly higher normalized PD volume (NPDV) versus collapsed PLN (0.553 ± 0.007 vs. 0.008 ± 0.003; p<0.05). Moreover, we define the upper (>0.030) and lower (<0.016) quartile NPDVs in this cohort of mice, which serve as conservative thresholds to phenotype PLN as expanding and collapsed, respectively. Interestingly, of the 12 PLN phenotyped by the two methods, there was disagreement in 4 cases in which they were determined to be expanding by CE-MRI and collapsed by PD-US. Since the adjacent knee had evidence of synovitis in all 4 cases, we concluded that the PD-US phenotyping was correct, and that this approach is currently the safest and most cost-effective in vivo approach to phenotype murine PLN as a biomarker of arthritic flare.
Celotno besedilo
Dostopno za:
DOBA, IZUM, KILJ, NUK, PILJ, PNG, SAZU, SIK, UILJ, UKNU, UL, UM, UPUK
Recent studies demonstrated lymphangiogenesis and expansion of draining lymph nodes during chronic inflammatory arthritis, and lymphatic dysfunction associated with collapse of draining lymph nodes ...in rheumatoid arthritis (RA) patients and TNF-transgenic (TNF-Tg) mice experiencing arthritic flare. As the intrinsic differences between lymphatic vessels afferent to healthy, expanding, and collapsed draining lymph nodes are unknown, we characterized the
behavior of popliteal lymphatic vessels (PLVs) from WT and TNF-Tg mice. We also interrogated the mechanisms of lymphatic dysfunction through inhibition of nitric oxide synthase (NOS).
Popliteal lymph nodes (PLNs) in TNF-Tg mice were phenotyped as Expanding or Collapsed by
ultrasound and age-matched to WT littermate controls. The PLVs were harvested and cannulated for
functional analysis over a relatively wide range of hydrostatic pressures (0.5-10 cmH
O) to quantify the end diastolic diameter (EDD), tone, amplitude (AMP), ejection fraction (EF), contraction frequency (FREQ), and fractional pump flow (FPF) with or without NOS inhibitors Data were analyzed using repeated measures two-way ANOVA with Bonferroni's
test.
Real time videos of the cannulated PLVs demonstrated the predicted phenotypes of robust vs. weak contractions of the WT vs. TNF-Tg PLV, respectively. Quantitative analyses confirmed that TNF-Tg PLVs had significantly decreased AMP, EF, and FPF vs. WT (
< 0.05). EF and FPF were recovered by NOS inhibition, while the reduction in AMP was NOS independent. No differences in EDD, tone, or FREQ were observed between WT and TNF-Tg PLVs, nor between Expanding vs. Collapsed PLVs.
These findings support the concept that chronic inflammatory arthritis leads to NOS dependent and independent draining lymphatic vessel dysfunction that exacerbates disease, and may trigger arthritic flare due to decreased egress of inflammatory cells and soluble factors from affected joints.
Proliferation of draining lymphatic vessels coupled with dynamic changes in lymph node volume and flow are characteristic features in rheumatoid arthritis (RA). Furthermore, impaired lymph egress ...from inflamed synovium is associated with joint flare in murine models of inflammatory-erosive arthritis. Unfortunately, advances towards a greater understanding of lymphatic changes in RA pathogenesis have been slow due to the absence of outcome measures to quantify lymphatic function in vivo. While lymphoscintigraphy is the current standard to assess lymphedema and sentinel lymph nodes in cancer patients, its sensitivity and specificity are inadequate to study lymphatics in RA. The emergence of high-resolution MRI, power Doppler ultrasound, and near-infrared imaging that permits real-time quantification of lymphatic function in animal models has been a major advance, and these techniques have produced a new paradigm of altered lymphatic function that underlies both acute arthritic flare and chronic inflammation. In acute flare, lymphatic drainage increases several fold, whereas no lymphatic contractions are detected in lymph vessels draining chronic arthritic joints. Moreover, these outcomes are now being adapted to study lymphatics in RA towards the development of novel biomarkers of arthritic flare and the discovery of new therapeutic targets. In particular, interventions that directly increase lymphatic egress from diseased joints by opening collateral lymphatic vessels, and that restore lymphatic vessel contractions, provide novel therapeutic approaches with potential for minimal toxicity and immunosuppression. To summarize the origins of this field, recent advances, and future directions, we herein review: current knowledge of lymphatics in RA based on classic literature; new in-vivo imaging modalities that have elucidated how lymphatics modulate acute versus chronic joint inflammation in murine models; and how these preclinical outcome measures are being translated to study lymphatic function in RA inflammation and how effective RA therapies alter lymphatic flow and lymph nodes draining flaring joints.
ClinicalTrials.gov NCT02680067 . Registered 7 December 2015; ClinicalTrials.gov NCT01098201 . Registered 30 March 2010; and ClinicalTrials.gov NCT01083563 . Registered 8 March 2010.
Nuclearite search with ANTARES Bouta, M.; Brunner, J.; Moussa, A. ...
Journal of instrumentation,
09/2021, Letnik:
16, Številka:
9
Journal Article
Recenzirano
Odprti dostop
The ANTARES detector is a Cherenkov underwater neutrino telescope operating in the Mediterranean Sea. Its construction was completed in 2008. Even though optimised for the search of cosmic neutrinos, ...this telescope is also sensitive to nuclearites (massive nuggets of strange quark matter) trough the black body radiation emitted along their path. We discuss here the possible detection of non-relativistic down-going nuclearites with the ANTARES telescope and present the results of an analysis using data collected from 2009 till 2017.
Objective
To investigate the roles of the synovial lymphatic system in the severity and progression of joint tissue damage and functional responses of synovial lymphatic endothelial cells (LECs) to ...macrophage subsets, and to evaluate the therapeutic potential of the proteasome inhibitor bortezomib (BTZ) in a mouse model of experimental posttraumatic osteoarthritis (OA).
Methods
C57BL/6J wild‐type mice received a meniscal ligamentous injury to induce posttraumatic knee OA. Lymphangiogenesis was blocked by a vascular endothelial growth factor receptor 3 (VEGFR‐3) neutralizing antibody. Synovial lymphatic drainage was examined by near‐infrared imaging. Joint damage was assessed by histology. RNA‐sequencing and pathway analyses were applied to synovial LECs. Macrophage subsets in the mouse synovium were identified by flow cytometry and immunofluorescence staining. M1 and M2 macrophages were induced from mouse bone marrow cells, and their effects on LECs were examined in cocultures in the presence or absence of BTZ. The effects of BTZ on joint damage, LEC inflammation, and synovial lymphatic drainage were examined.
Results
Injection of a VEGFR‐3 neutralizing antibody into the joints of mice with posttraumatic knee OA reduced synovial lymphatic drainage and accelerated joint tissue damage. Synovial LECs from the mouse OA joints had dysregulated inflammatory pathways and expressed high levels of inflammatory genes. The number of M1 macrophages was increased in the knee joints of mice with posttraumatic OA, thereby promoting the expression of inflammatory genes by LECs; this effect was blocked by BTZ. Treatment with BTZ decreased cartilage loss, reduced the expression of inflammatory genes by LECs, and improved lymphatic drainage in the knee joints of mice with posttraumatic OA.
Conclusion
Experimental posttraumatic knee OA is associated with decreased synovial lymphatic drainage, increased numbers of M1 macrophages, and enhanced inflammatory gene expression by LECs, all of which was improved by treatment with BTZ. Intraarticular administration of BTZ may represent a new therapy for the restoration of synovial lymphatic function in subjects with posttraumatic knee OA.
Lymphedema arises from impaired lymphatic function. Quantification of lymphatic contractility has previously been shown using a custom-built near-infrared imaging system. However, to broaden the ...clinical use of functional lymphatic measurements, these measurements need to be performed using a standard-of-care, clinically available camera. The authors propose an objective, algorithmic, and clinically accessible approach to quantify lymphatic contractility using a 3-minute indocyanine green lymphangiograph recorded with a commercially available near-infrared camera. A retrospective review of the authors’ indocyanine green lymphangiography video repository maintained in a Research Electronic Data Capture database was performed. All patients with a newly diagnosed unilateral breast cancer undergoing preoperative indocyanine green lymphangiography were included in the analysis. Patient medical records were then analyzed for patient demographics, and videos were analyzed for contractility. Seventeen consecutive patients with unilateral breast cancers underwent video processing to quantify lymphatic contractility of the ipsilateral extremity in contractions per minute. All patients were women, with an average age of 60.5 years (range, 38 to 84 years). The average lymphatic contractility rate was 1.13 contractions per minute (range, 0.67 to 2.5 contractions per minute). Using a clinically accessible standard-of-care device for indocyanine green lymphangiography, the authors were able to determine lymphatic contractility rates of a normal extremity. The authors’ finding falls within the range of previously published data quantifying lymphatic contractility using a research device, suggesting that the authors’ technique provides a clinically accessible, time-effective means of assessing lymphatic contractility. Potential future applications include both lymphedema surveillance and evaluation of nonsurgical and surgical interventions.
CLINICAL QUESTION/LEVEL OF EVIDENCE:Diagnostic, IV.
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