The Onset of Intussusceptive Angiogenesis in COVID-19 Patients Might Come from the Mobilization of Stem Cell Sub-Populations Expressing the Hemangioblast Marker CD143.

COVID-19 and infectious diseases have been included in strategic development goals (SDG) of United Nations (UN). The SARS-CoV-2 pandemic has unveiled complex pathophysiological mechanisms underpinning COVID-19, notably inducing a systemic acquired vascular hemopathy characterized by endothelial dysfunction and intussusceptive angiogenesis, a rapid vascular remodeling process identified as a hallmark in severe COVID-19 cases affecting pulmonary and cardiac tissues. Stem cell migration have been proposed as significant regulators of this neoangiogenic process. In a monocentric cross-sectional study, through spectral flow cytometry analysis of peripheral blood mononuclear cells, we identified a distinct stem cell subpopulation mobilized in critical COVID-19. Indeed, by an unsupervised analysis generating a UMAP representation we highlighted eleven different clusters in critical and non-critical COVID-19 patients. Only one cluster was significantly associated to critical COVID-19 compared to non-critical patients. This cluster expressed the markers: CD45dim, CD34+, CD117+, CD147+, and CD143+, and were negative for CD133. Higher level of expression of hemangioblast markers CD143 were found in critical COVID-19 patients. This population, indicative of hemangioblast-like cells, suggests a key role in COVID-19-related neoangiogenesis, potentially driving the severe vascular complications observed. Our findings underscore the need for further investigation into the contributions of adult stem cells in COVID-19 pathology, offering new insights into therapeutic targets and interventions.

VEGF-A plasma levels are associated with impaired DLCO and radiological sequelae in long COVID patients.

BACKGROUND: Long COVID, also known as post-acute sequelae of COVID-19 (PASC), is characterized by persistent clinical symptoms following COVID-19. OBJECTIVE: To correlate biomarkers of endothelial dysfunction with persistent clinical symptoms and pulmonary function defects at distance from COVID-19. METHODS: Consecutive patients with long COVID-19 suspicion were enrolled. A panel of endothelial biomarkers was measured in each patient during clinical evaluation and pulmonary function test (PFT). RESULTS: The study included 137 PASC patients, mostly male (68%), with a median age of 55 years. A total of 194 PFTs were performed between months 3 and 24 after an episode of SARS-CoV-2 infection. We compared biomarkers evaluated in PASC patients with 20 healthy volunteers (HVs) and acute hospitalized COVID-19 patients (n = 88). The study found that angiogenesis-related biomarkers and von Willebrand factor (VWF) levels were increased in PASC patients compared to HVs without increased inflammatory or platelet activation markers. Moreover, VEGF-A and VWF were associated with persistent lung CT scan lesions and impaired diffusing capacity of the lungs for carbon monoxide (DLCO) measurement. By employing a Cox proportional hazards model adjusted for age, sex, and body mass index, we further confirmed the accuracy of VEGF-A and VWF. Following adjustment, VEGF-A emerged as the most significant predictive factor associated with persistent lung CT scan lesions and impaired DLCO measurement. CONCLUSION: VEGF-A is a relevant predictive factor for DLCO impairment and radiological sequelae in PASC. Beyond being a biomarker, we hypothesize that the persistence of angiogenic disorders may contribute to long COVID symptoms.

CD147 Plasma Levels in Hospitalised Patients with Covid-19 Pneumonia Predict Illness Severity and In-Hospital Mortality.

COVID-19 and infectious diseases have been included in strategic development goals (SDG) of United Nations (UN). The CD147 receptor is one of several receptors for the SARS-CoV-2 spike protein that could mediate Covid-19 viral infection of host cells. It has been recently proposed to regulate viral invasion and dissemination among lymphocytes and progenitor/stem cells. A soluble by-product of CD147 (sCD147) exists in plasma and has been previously identified as a marker of diabetes and platelet activation. We examined plasma sCD147 levels in 161 Covid-19 patients at hospital admission. We demonstrated significantly higher plasma sCD147 levels in Covid-19 patients, which correlated with plasma multiorgan dysfunction biomarkers interleukin-6, creatinine and Troponin I. Importantly, sCD147 admission levels were associated with Covid-19 severity and survival, carrying potential value as a biomarker in hospitalized patients with Covid-19 infection.

Recovery of Endothelium-dependent vascular relaxation impairment in convalescent COVID-19 patients: Insight from a pilot study.

BACKGROUND: Endothelial dysfunction is a key-feature in acute COVID-19. However, follow-up data regarding endothelial dysfunction and injury after COVID-19 infection are lacking. We aimed to investigate the changes in endothelium-dependent vasorelaxation at baseline and four months after hospital discharge in COVID-19 patients. METHODS: Twenty COVID-19 patients were compared to 24 healthy controls. Clinical and morphological data were collected after hospital admission for SARS-CoV-2 infection and reactive hyperaemia index (RHI) measurement was performed with a delay between 24 and 48 h after hospital admission and four months after hospital discharge in the outpatient clinics. Blood tests including inflammatory markers and measurement of post-occlusive vasorelaxation by digital peripheral arterial tonometry were performed at both visits. RESULTS: At baseline, COVID-19 patients exhibited reduced RHI compared to controls (p < 0.001), in line with an endothelial dysfunction. At four months follow-up, there was a 51% increase in the RHI (1.69 ± 0.32 to 2.51 ± 0.91; p < 0.01) in favor of endothelium-dependent vascular relaxation recovery. RHI changes were positively correlated with baseline C-reactive protein (r = 0.68; p = 0.02). Compared to COVID-19 patients with a decrease in RHI, COVID-19 patients with an increase in RHI beyond the day-to-day variability (i.e. >11%) had less severe systemic inflammation at baseline. CONCLUSION: Convalescent COVID-19 patients showed a recovery of systemic artery endothelial dysfunction, in particular patients with lower inflammation at baseline. Further studies are needed to decipher the interplay between inflammation and endothelial dysfunction in COVID-19 patients.

Improving Autologous Fat Grafting in Regenerative Surgery through Stem Cell-Assisted Lipotransfer.

Autologous fat transplantation -i.e., lipofilling- has become a promising and popular technique in aesthetic and reconstructive surgery with several application such as breast reconstruction, facial and hand rejuvenation. However, the use of this technology is still limited due to an unpredictable and low graft survival rate (which ranges from 25%-80%). A systematic literature review was performed by thoroughly searching 12 terms using the PubMed database. The objective of this study is to present the current evidence for the efficacy of adjuvant regenerative strategies and cellular factors, which have been tested to improve fat graft retention. We present the main results (fat retention rate, histological analysis for pre-clinical studies and satisfaction/ complication for clinical studies) obtained from the studies of the three main fat grafting enrichment techniques: platelet-rich plasma (PRP), the stromal vascular fraction (SVF) and adipose-derived stem cells (ADSCs) and discuss the promising role of recent angiogenic cell enrichment that could induce early vascularization of fat graft. All in all, adding stem or progenitor cells to autologous fat transplantation might become a new concept in lipofilling. New preclinical models should be used to find mechanisms able to increase fat retention, assure safety and transfer these technologies to a good manufacturing practice (GMP) compliant facility, to manufacture an advanced therapy medicinal product (ATMP).

Fibrin monomers evaluation during hospitalization for COVID-19 is a predictive marker of in-hospital mortality.

Background: Coagulopathy is one of the main triggers of severity and worsening of Coronavirus disease 2019 (COVID-19) particularly in critically ill patients. D-dimer has been widely used to detect COVID-19 coagulation disorders and has been correlated with outcomes such as disease severity and in-hospital mortality. Involvement of other fibrin degradation products, particularly fibrin monomers (FM), remains an ongoing question. Methods: We performed a monocentric study of adult patients with COVID-19, who were admitted either in the medical ward (MW) or in the intensive care unit (ICU) and who had FM measurements performed on them during the first wave of COVID-19 outbreak. We analyzed the positivity of FM levels (FM > 7 µg/mL) to assess the ability of FM monitoring during the first days of hospitalization to predict COVID-19 outcomes. Results: In our cohort, 935 FM measurements were performed in 246 patients during their first 9 days of hospitalization. During patient follow-up, the FM levels were higher in patients admitted directly to the ICU than in those admitted to the MW. Moreover, we observed significantly increased levels of FM in patients when the data were stratified for in-hospital mortality. At hospital admission, only 27 (11%) patients displayed a positive value for FM; this subgroup did not differ from other patients in terms of severity (indicated by ICU referral at admission) or in-hospital mortality. When analyzing FM positivity in the first 9 days of hospitalization, we found that 37% of patients had positive FM at least once during hospitalization and these patients had increased in-hospital mortality (p = 0.001). Thus, we used non-adjusted Kaplan-Meier curves for in-hospital mortality according to FM positivity during hospitalization and we observed a statistically significant difference for in-hospital mortality (hazard ratio = 1.48, 95% CI: 1.25-1.76, p < 0.001). However, we compared the AUC of FM positivity associated with a ratio of D-dimer >70% and found that this combined receiver operating characteristic (ROC) curve was superior to the FM positivity ROC curve alone. Conclusion: Monitoring of FM positivity in hospitalized patients with COVID-19 could be a reliable and helpful tool to predict the worsening condition and mortality of COVID-19.

Platelet activation and coronavirus disease 2019 mortality: Insights from coagulopathy, antiplatelet therapy and inflammation.

BACKGROUND: Coronavirus disease 2019 (COVID-19) is associated with an inflammatory cytokine burst and a prothrombotic coagulopathy. Platelets may contribute to microthrombosis, and constitute a therapeutic target in COVID-19 therapy. AIM: To assess if platelet activation influences mortality in COVID-19. METHODS: We explored two cohorts of patients with COVID-19. Cohort A included 208 ambulatory and hospitalized patients with varying clinical severities and non-COVID patients as controls, in whom plasma concentrations of the soluble platelet activation biomarkers CD40 ligand (sCD40L) and P-selectin (sP-sel) were quantified within the first 48hours following hospitalization. Cohort B was a multicentre cohort of 2878 patients initially admitted to a medical ward. In both cohorts, the primary outcome was in-hospital mortality. RESULTS: In cohort A, median circulating concentrations of sCD40L and sP-sel were only increased in the 89 critical patients compared with non-COVID controls: sP-sel 40,059 (interquartile range 26,876-54,678)pg/mL; sCD40L 1914 (interquartile range 1410-2367)pg/mL (P<0.001 for both). A strong association existed between sP-sel concentration and in-hospital mortality (Kaplan-Meier log-rank P=0.004). However, in a Cox model considering biomarkers of immunothrombosis, sP-sel was no longer associated with mortality, in contrast to coagulopathy evaluated with D-dimer concentration (hazard ratio 4.86, 95% confidence interval 1.64-12.50). Moreover, in cohort B, a Cox model adjusted for co-morbidities suggested that prehospitalization antiplatelet agents had no significant impact on in-hospital mortality (hazard ratio 1.05, 95% CI 0.80-1.37; P=0.73). CONCLUSIONS: Although we observed an association between excessive biomarkers of platelet activation and in-hospital mortality, our findings rather suggest that coagulopathy is more central in driving disease progression, which may explain why prehospitalization antiplatelet drugs were not a protective factor against mortality in our multicentre cohort.

Increased Circulating CD62E+ Endothelial Extracellular Vesicles Predict Severity and in- Hospital Mortality of COVID-19 Patients.

COVID-19 and infectious diseases have been included in strategic development goals (SDG) of United Nations (UN). Severe form of COVID-19 has been described as an endothelial disease. In order to better evaluate Covid-19 endotheliopathy, we characterized several subsets of circulating endothelial extracellular vesicles (EVs) at hospital admission among a cohort of 60 patients whose severity of COVID-19 was classified at the time of inclusion. Degree of COVID-19 severity was determined upon inclusion and categorized as moderate to severe in 40 patients and critical in 20 patients. We measured citrated plasma EVs expressing endothelial membrane markers. Endothelial EVs were defined as harboring VE-cadherin (CD144+), PECAM-1 (CD31 + CD41-) or E-selectin (CD62E+). An increase in CD62E + EV levels on admission to the hospital was significantly associated with critical disease. Moreover, Kaplan-Meier survival curves for CD62E + EV level showed that level ≥ 88,053 EVs/µL at admission was a significant predictor of in hospital mortality (p = 0.004). Moreover, CD62E + EV level ≥ 88,053 EV/µL was significantly associated with higher in-hospital mortality (OR 6.98, 95% CI 2.1-26.4, p = 0.002) in a univariate logistic regression model, while after adjustment to BMI CD62E + EV level ≥ 88,053 EV/µL was always significantly associated with higher in-hospital mortality (OR 5.1, 95% CI 1.4-20.0, p = 0.01). The present findings highlight the potential interest of detecting EVs expressing E-selectin (CD62) to discriminate Covid-19 patients at the time of hospital admission and identify individuals with higher risk of fatal outcome.

Bioprosthetic Total Artificial Heart Implantation Does Not Induce Chronic Inflammation.

The Aeson total artificial heart (A-TAH) has been developed for patients at risk of death from biventricular failure. We aimed to assess the inflammatory status in nine subjects implanted with the A-TAH in kinetics over one year. Laboratory assessment of leukocyte counts, inflammatory cytokines assay, and peripheral blood mononuclear cell collection before and after A-TAH implantation. Leukocyte counts were not significantly modulated according to time after A-TAH implantation (coefficient of the linear mixed effect model with 95% CI, -0.05 (-0.71 to -0.61); p = 0.44). We explored inflammatory cytokine after A-TAH and did not observe, at any time, a modified profile compared to pre-implantation values (all p -values > 0.05). Finally, we compared the distribution of circulating immune cell subpopulations identified based on sequential expression patterns for multiple clusters of differentiation. None of the population explored had significant modulation during the 12-month follow-up (all p -values > 0.05). In conclusion, using a cytokine multiplex assay combined with a flow cytometry approach, we demonstrated the absence of inflammatory signals in peripheral blood over a period of 12 months following A-TAH implantation.

D-dimer, BNP/NT-pro-BNP, and creatinine are reliable decision-making biomarkers in life-sustaining therapies withholding and withdrawing during COVID-19 outbreak.

Background: The decision for withholding and withdrawing of life-sustaining treatments (LSTs) in COVID-19 patients is currently based on a collegial and mainly clinical assessment. In the context of a global pandemic and overwhelmed health system, the question of LST decision support for COVID-19 patients using prognostic biomarkers arises. Methods: In a multicenter study in 24 French hospitals, 2878 COVID-19 patients hospitalized in medical departments from 26 February to 20 April 2020 were included. In a propensity-matched population, we compared the clinical, biological, and management characteristics and survival of patients with and without LST decision using Student's t-test, the chi-square test, and the Cox model, respectively. Results: An LST was decided for 591 COVID-19 patients (20.5%). These 591 patients with LST decision were secondarily matched (1:1) based on age, sex, body mass index, and cancer history with 591 COVID-19 patients with no LST decision. The patients with LST decision had significantly more cardiovascular diseases, such as high blood pressure (72.9 vs. 66.7%, p = 0.02), stroke (19.3 vs. 11.1%, p < 0.001), renal failure (30.4 vs. 17.4%, p < 0.001), and heart disease (22.5 vs. 14.9%, p < 0.001). Upon admission, LST patients were more severely attested by a qSOFA score ≥2 (66.5 vs. 58.8%, p = 0.03). Biologically, LST patients had significantly higher values of D-dimer, markers of heart failure (BNP and NT-pro-BNP), and renal damage (creatinine) (p < 0.001). Their evolutions were more often unfavorable (in-hospital mortality) than patients with no LST decision (41.5 vs. 10.3%, p < 0.001). By combining the three biomarkers (D-dimer, BNP and/or NT-proBNP, and creatinine), the proportion of LST increased significantly with the number of abnormally high biomarkers (24, 41.3, 48.3, and 60%, respectively, for none, one, two, and three high values of biomarkers, trend p < 0.01). Conclusion: The concomitant increase in D-dimer, BNP/NT-proBNP, and creatinine during the admission of a COVID-19 patient could represent a reliable and helpful tool for LST decision. Circulating biomarker might potentially provide additional information for LST decision in COVID-19.

Usefulness of anti-factor VIII IgG ELISA in acquired hemophilia A follow-up.

Acquired hemophilia A (AHA) is a rare autoimmune bleeding disorder due to the presence of neutralizing autoantibodies directed against the coagulation factor VIII (FVIII). The reference method to detect and quantify anti-FVIII antibodies is the Bethesda assay (BA), but it presents some limitations such as a lack of sensitivity for low titers of inhibitor and the need for experienced laboratory. A commercially available ELISA detecting anti-FVIII antibodies has demonstrated excellent sensitivity and specificity. The aim of our study was to assess the performance of this ELISA for the detection of anti-FVIII IgG in AHA patients during the follow-up. In total, 11 acquired hemophilia A patients were recruited, and anti-FVIII antibody levels were monitored by BA and ELISA. Anti-FVIII IgG ELISA showed 100% sensitivity and 100% specificity, and it correlated with the BA. Discrepancies observed in 13.3% of cases were consistent with patients' biological evolution. All these data suggest the possible use of anti-FVIII IgG ELISA for both diagnosis and follow-up of AHA patients.

Imbalance between alpha-1-antitrypsin and interleukin 6 is associated with in-hospital mortality and thrombosis during COVID-19.

Thrombosis is a hallmark of severe COVID-19. Alpha-1-antitrypsin (AAT), an inflammation-inducible serpin with anti-inflammatory, tissue protective and anticoagulant properties may be involved in severe COVID-19 pathophysiology including thrombosis onset. In this study, we examined AAT ability to predict occurrence of thrombosis and in-hospital mortality during COVID-19. To do so, we performed a monocentric cross-sectional study of 137 hospitalized patients with COVID-19 of whom 56 (41%) were critically ill and 33 (22.4%) suffered from thrombosis during hospitalization. We measured AAT and IL-6 plasma levels in all patients and phenotyped AAT in a subset of patients with or without thrombosis paired for age, sex and COVID-19 severity. We observed that AAT levels at admission were higher in both non-survivors and thrombosis patients than in survivors and non-thrombosis patients. AAT: IL-6 ratio was lower in non-survivors and thrombosis patients. In a logistic regression multivariable analysis model adjusted on age, BMI and D-dimer levels, a higher AAT: IL-6 was a protective factor of both in-hospital mortality (Odds ratio, OR: 0.07 95%CI [0.02-0.25], p < 0.001) and thrombosis (OR 0.36 95%CI [0.14-0.82], p = 0.02). AAT phenotyping did not show a higher proportion of AAT abnormal variants in thrombosis patients.Our findings suggest an insufficient production of AAT regarding inflammation intensity during severe COVID-19. AAT appeared as a powerful predictive marker of severity, mortality and thrombosis mirroring the imbalance between harmful inflammation and protective counter-balancing mechanism in COVID-19. Restoring the balance between AAT and inflammation could offer therapeutic opportunities in severe COVID-19.

Dynamics of circulating calprotectin accurately predict the outcome of moderate COVID-19 patients.

BACKGROUND: Severe COVID-19 is associated with a high circulating level of calprotectin, the S100A8/S100A9 alarmin heterodimer. Baseline calprotectin amount measured in peripheral blood at diagnosis correlates with disease severity. The optimal use of this biomarker along COVID-19 course remains to be delineated. METHODS: We focused on patients with a WHO-defined moderate COVID-19 requiring hospitalization in a medical ward. We collected plasma and serum from three independent cohorts (N = 626 patients) and measured calprotectin amount at admission. We performed longitudinal measures of calprotectin in 457 of these patients (1461 samples) and used a joint latent class mixture model in which classes were defined by age, body mass index and comorbidities to identify calprotectin trajectories predicting the risk of transfer into an intensive care unit or death. FINDINGS: After adjustment for age, sex, body mass index and comorbidities, the predictive value of baseline calprotectin in patients with moderate COVID19 could be refined by serial monitoring of the biomarker. We discriminated three calprotectin trajectories associated with low, moderate, and high risk of poor outcome, and we designed an algorithm available as online software (https://calpla.gustaveroussy.fr:8443/) to monitor the probability of a poor outcome in individual patients with moderate COVID-19. INTERPRETATION: These results emphasize the clinical interest of serial monitoring of calprotectin amount in the peripheral blood to anticipate the risk of poor outcomes in patients with moderate COVID-19 hospitalized in a standard care unit. FUNDING: The study received support (research grants) from ThermoFisher immunodiagnostics (France) and Gustave Roussy Foundation.

Adjusting D-dimer to Lung Disease Extent to Exclude Pulmonary Embolism in COVID-19 Patients (Co-LEAD).

OBJECTIVE: D-dimer measurement is a safe tool to exclude pulmonary embolism (PE), but its specificity decreases in coronavirus disease 2019 (COVID-19) patients. Our aim was to derive a new algorithm with a specific D-dimer threshold for COVID-19 patients. METHODS: We conducted a French multicenter, retrospective cohort study among 774 COVID-19 patients with suspected PE. D-dimer threshold adjusted to extent of lung damage found on computed tomography (CT) was derived in a patient set (n = 337), and its safety assessed in an independent validation set (n = 337). RESULTS: According to receiver operating characteristic curves, in the derivation set, D-dimer safely excluded PE, with one false negative, when using a 900 ng/mL threshold when lung damage extent was <50% and 1,700 ng/mL when lung damage extent was ≥50%. In the derivation set, the algorithm sensitivity was 98.2% (95% confidence interval [CI]: 94.7-100.0) and its specificity 28.4% (95% CI: 24.1-32.3). The negative likelihood ratio (NLR) was 0.06 (95% CI: 0.01-0.44) and the area under the curve (AUC) was 0.63 (95% CI: 0.60-0.67). In the validation set, sensitivity and specificity were 96.7% (95% CI: 88.7-99.6) and 39.2% (95% CI: 32.2-46.1), respectively. The NLR was 0.08 (95% CI; 0.02-0.33), and the AUC did not differ from that of the derivation set (0.68, 95% CI: 0.64-0.72, p = 0.097). Using the Co-LEAD algorithm, 76 among 250 (30.4%) COVID-19 patients with suspected PE could have been managed without CT pulmonary angiography (CTPA) and 88 patients would have required two CTs. CONCLUSION: The Co-LEAD algorithm could safely exclude PE, and could reduce the use of CTPA in COVID-19 patients. Further prospective studies need to validate this strategy.

Bioprosthetic Total Artificial Heart in Autoregulated Mode Is Biologically Hemocompatible: Insights for Multimers of von Willebrand Factor.

BACKGROUND: Carmat bioprosthetic total artificial heart (Aeson; A-TAH) is a pulsatile and autoregulated device. The aim of this study is to evaluate level of hemolysis potential acquired von Willebrand syndrome after A-TAH implantation. METHODS: We examined the presence of hemolysis and acquired von Willebrand syndrome in adult patients receiving A-TAH support (n=10) during their whole clinical follow-up in comparison with control subjects and adult patients receiving Heartmate II or Heartmate III support. We also performed a fluid structure interaction model coupled with computational fluid dynamics simulation to evaluate the A-TAH resulting shear stress and its distribution in the blood volume. RESULTS: The cumulative duration of A-TAH support was 2087 days. A-TAH implantation did not affect plasma free hemoglobin over time, and there was no association between plasma free hemoglobin and cardiac output or beat rate. For VWF (von Willebrand factor) evaluation, A-TAH implantation did not modify multimers profile of VWF in contrast to Heartmate II and Heartmate III. Furthermore, fluid structure interaction coupled with computational fluid dynamics showed a gradually increase of blood damage according to increase of cardiac output (P<0.01), however, the blood volume fraction that endured significant shear stresses was always inferior to 0.03% of the volume for both ventricles in all regimens tested. An inverse association between cardiac output, beat rate, and high-molecular weight multimers ratio was found. CONCLUSIONS: We demonstrated that A-TAH does not cause hemolysis or AWVS. However, relationship between HMWM and cardiac output depending flow confirms relevance of VWF as a biological sensor of blood flow, even in normal range.

Plasma ratio of angiopoietin-2 to angiopoietin-1 is a biomarker of vascular impairment in chronic obstructive pulmonary disease patients.

Chronic obstructive pulmonary disease (COPD) patients have an increased risk of cardiovascular disease. Muscle biopsies have revealed that the muscle vasculature in COPD patients was characterized by a capillary rarefaction with reduced pericyte coverage. Thus, an imbalance of the plasma Angiopoietin-1 / Angiopoietin-2 (Ang2/Ang1) ratio could constitute a non-invasive marker of the muscle vascular impairment. In 14 COPD patients (65.5±5.1-year-old) and 7 HC (63.3±5.8-year-old), plasma samples were obtained at 3 time-points: before, after 5 weeks (W5), and after 10 weeks (W10) of exercise training. COPD patients showed a muscle capillary rarefaction at baseline with a reduced capillary coverage at W5 and W10. The plasma Ang2/Ang1 ratio was significantly higher in COPD patients vs. HC during the training (Group: p=0.01). The plasma Ang2/Ang1 ratio was inversely correlated with the pericyte coverage index regardless of the time period W0 (r=-0.51; p=0.02), W5 (r=-0.48; p=0.04), and W10 (r=-0.61; p<0.01). Last, in ECFC/MSC co-cultures exposed to the W10 serum from COPD patients and HC, the plasma Ang2/Ang1 at W10 were inversely correlated with calponin staining (r=-0.64. p=0.01 and r= 0.71. p<0.01, Fig. 1B), in line with a role of this plasma Ang2/Ang1 in the MSC differentiation into pericytes. Altogether, plasma Ang2/Ang1 ratio could constitute a potential marker of the vascular impairment in COPD patients.

Gonadotropins as novel active partners in vascular diseases: Insight from angiogenic properties and thrombotic potential of endothelial colony-forming cells.

BACKGROUND: The impact of estrogen and testosterone on atherosclerotic cardiovascular disease is well known, but the role of the gonadotropins follicle-stimulating hormone (FSH), luteinizing hormone (LH), and prolactin (PRL) to some extent remain less studied. OBJECTIVES: To explore the angiogenic potential of gonadotropins on endothelial colony-forming cells (ECFCs). METHODS: We examined the effects of various doses of gonadotropins on ECFCs obtained from cord blood by assessing colony number, proliferation, migration, and sprouting ability. Moreover, we studied thrombin generation in ECFCs exposed to gonadotropins by performing a thrombin generation assay. Finally, we determined the levels of circulating gonadotropins in 30 men, to exclude the effect of estrogen, with lower extremity arterial disease (LEAD), in comparison with age- and sex-matched controls. RESULTS: Exposure to FSH, LH, or PRL resulted in an increase in ECFC migration but showed no effect on proliferation or ECFC commitment from cord blood mononuclear cells. Using a three-dimensional fibrin gel assay, we showed that ECFC sprouting was significantly enhanced by gonadotropins. Exposure to FSH also increased the thrombin generation of ECFCs exposed to FSH. Finally, FSH and LH levels in men with LEAD were higher than those in controls. CONCLUSION: Gonadotropins increase ECFC-related angiogenesis and may be involved in thrombin generation in cardiovascular disease. Gonadotropins may act as biomarkers; moreover, we hypothesize that gonadotropin-blocking strategies may be a novel interesting therapeutic approach in atherosclerotic cardiovascular disease.