Platelet expression and reactivity after BNT162b2 vaccine administration

SARS-CoV-2 infection induces a coagulopathy characterized by platelet activation and a hypercoagulable state with an increased incidence of cardiovascular events. The viral spike protein S has been reported to enhance thrombosis formation, stimulate platelets to release pro-coagulant factors and promote the formation of platelet-leukocyte aggregates even in absence of the virus. Although SARS-CoV-2 vaccines induce spike protein overexpression to trigger SARS-CoV-2-specific immune protection, thrombocyte activity has not been investigated in this context. Here, we provide the first phenotypic platelet characterization of healthy human subjects undergoing BNT162b2 vaccination. Using mass cytometry, we analyzed the expression of constitutive transmembrane receptors, adhesion proteins and platelet activation markers in 12 healthy donors before and at five different timepoints within four weeks after the first BNT162b2 administration. We measured platelet reactivity by stimulating thrombocyte activation with thrombin receptor-activating peptide (TRAP). Activation marker expression (P-Selectin, LAMP-3, LAMP-1, CD40L and PAC-1) did not change after vaccination. All investigated constitutive transmembrane proteins showed similar expressions over time. Platelet reactivity was not altered after BNT162b2 administration. Activation marker expression was significantly lower compared to an independent cohort of mild symptomatic COVID-19 patients analyzed with the same platform. This study reveals that BNT162b2 administration does not alter platelet protein expression and reactivity.

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Effect of ultrapure lipopolysaccharides derived from diverse bacterial species on the modulation of platelet activation

Scientific Reports ◽

10.1038/s41598-019-54617-w ◽

2019 ◽

Vol 9 (1) ◽

Cited By ~ 4

Author(s):

Thomas M. Vallance ◽

Divyashree Ravishankar ◽

Dina A. I. Albadawi ◽

Harry Layfield ◽

Jonathan Sheard ◽

...

Keyword(s):

Platelet Activation ◽

Platelet Reactivity ◽

Platelet Rich Plasma ◽

Bacterial Species ◽

Human Platelets ◽

Innate Immune Responses ◽

Experimental Conditions ◽

Activation Markers ◽

The Impact ◽

Inside Out

AbstractPlatelets are small circulating blood cells that play essential roles in the maintenance of haemostasis via blood clotting. However, they also play critical roles in the regulation of innate immune responses. Inflammatory receptors, specifically Toll-like receptor (TLR)-4, have been reported to modify platelet reactivity. A plethora of studies have reported controversial functions of TLR4 in the modulation of platelet function using various chemotypes and preparations of its ligand, lipopolysaccharide (LPS). The method of preparation of LPS may explain these discrepancies however this is not fully understood. Hence, to determine the impact of LPS on platelet activation, we used ultrapure preparations of LPS from Escherichia coli (LPSEC), Salmonella minnesota (LPSSM), and Rhodobacter sphaeroides (LPSRS) and examined their actions under diverse experimental conditions in human platelets. LPSEC did not affect platelet activation markers such as inside-out signalling to integrin αIIbβ3 or P-selectin exposure upon agonist-induced activation in platelet-rich plasma or whole blood whereas LPSSM and LPSRS inhibited platelet activation under specific conditions at supraphysiological concentrations. Overall, our data demonstrate that platelet activation is not largely influenced by any of the ultrapure LPS chemotypes used in this study on their own except under certain conditions.

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Effect of imprime PGG on innate immune-activating pharmacodynamic changes in a phase I clinical study in healthy human volunteers.

Journal of Clinical Oncology ◽

10.1200/jco.2017.35.7_suppl.33 ◽

2017 ◽

Vol 35 (7_suppl) ◽

pp. 33-33 ◽

Cited By ~ 1

Author(s):

Nandita Bose ◽

Nadine Ottoson ◽

Ben Harrison ◽

Jamie R. Lowe ◽

Mark Matson ◽

...

Keyword(s):

B Cells ◽

Checkpoint Inhibitors ◽

Human Subjects ◽

Fold Increase ◽

Innate Immune ◽

Marker Genes ◽

Beta Glucan ◽

Healthy Human ◽

Activation Markers ◽

Pre Treatment

33 Background: Imprime PGG (Imprime) is currently in clinical development as combination therapy with checkpoint inhibitors. Imprime, a yeast-derived, soluble β-1,3/1,6 glucan is a Pathogen Associated Molecular Pattern (PAMP) that complexes with endogenous anti-beta glucan antibodies (ABA) and activates innate immune effector cells to trigger the anti-cancer immunity cycle. In this study, we sought to investigate the immunopharmacodynamic (IPD) responses of Imprime in healthy human subjects. Methods: Group 1 (n=12) received a single IV infusion of Imprime 4 mg/kg, Group 2 (n=12) received three weekly infusions of 4mg/kg Imprime. Group 3 (n=12) received infusions of 4 mg/kg or 2 mg/kg Imprime on weeks 1, 2 and 5. In groups 1 and 2, six subjects each received premedication with diphenhydramine 50 mg IV and dexamethasone 8 mg IV. IPD changes were measured at various times before, during and after Imprime administration. Results: Peak levels of complement activation products, C5a and SC5b-9 were detected at the end of infusion (EOI). A 2 to 3-fold increase in neutrophil and monocyte numbers were seen 4 hours post-Imprime infusion. Chemokines, especially IL-8 and MCP-1, were consistently detected at EOI. Cellular analyses showed Imprime binding to neutrophils, monocytes, subsets of DC and B cells. 24 hrs after EOI, a population of intermediate monocytes expressing higher levels of the activation markers CD86, PD-L1, and HLA-DR, was observed. Approximately one week post-Imprime, increased switched memory B cells and plasmablasts were detected. Consistent increase in expression of innate immune activation marker genes was evident as well. A substantial drop in free ABA and a concomitant increase in circulating immune complexes were seen at the EOI. Adverse events (AE) were limited to infusion related reactions. Importantly, the IPD changes and the AE were seen in subjects with higher ABA levels. The effect of pre-medications on some of the IPD will also be presented. Conclusions: These human data provide the first evidence linking pre-treatment ABA levels and Imprime IPD, substantiating the use of these pre-treatment ABA levels for patient selection.

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In vivo platelet activation and platelet hyperreactivity in abacavir-treated HIV-infected patients

Thrombosis and Haemostasis ◽

10.1160/th12-07-0504 ◽

2013 ◽

Vol 110 (08) ◽

pp. 349-357 ◽

Cited By ~ 35

Author(s):

Barbara Belfiori ◽

Eleonora Petito ◽

Giuseppe Guglielmini ◽

Lisa Malincarne ◽

AnnaMaria Mezzasoma ◽

...

Keyword(s):

Platelet Activation ◽

Cardiovascular Events ◽

Light Transmission ◽

Ex Vivo ◽

Platelet Reactivity ◽

Retrospective Case ◽

Activation Markers ◽

Induced Aggregation

SummaryAbacavir (ABC) has been associated with ischaemic cardiovascular events in HIV-infected patients, but the pathogenic mechanisms are unknown. Aim of our study was to assess whether ABC induces in vivo platelet activation and ex vivo platelet hyper-reactivity. In a retrospective, case-control study, in vivo platelet activation markers were measured in 69 HIV-infected patients, before starting therapy and after 6–12 months of either ABC (n=35) or tenofovir (TDF) (n=34), and compared with those from 20 untreated HIV-infected patients. A subgroup of patients was restudied after 28–34 months for ex vivo platelet reactivity. In vivo platelet activation markers were assessed by ELISA or flow cytometry, ex vivo platelet reactivity by light transmission aggregometry (LTA) and PFA-100®. The in vitro effects of the ABC metabolite, carbovir triphosphate, on aggregation and intra-platelet cGMP were also studied. sPLA2, sPsel and sGPV increased significantly 6–12 months after the beginning of ABC, but not of TDF or of no treatment. Ex vivo platelet function studies showed enhanced LTA, shorter PFA-100® C/ADP closure time and enhanced platelet expression of P-sel and CD40L in the ABC group. The intake of ABC blunted the increase of intraplatelet cGMP induced by nitric oxide (NO) and acutely enhanced collagen-induced aggregation. Preincubation of control platelets with carbovir triphosphate in vitro enhanced platelet aggregation and blunted NO-induced cGMP elevation. In conclusion, treatment with ABC enhances in vivo platelet activation and induces platelet hyperreactivity by blunting the inhibitory effects of NO on platelets. These effects may lead to an increase of ischaemic cardiovascular events.

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Dabigatran Treatment Increased Closure Device-Related Thrombosis by Platelet Activation in Patients Undergoing Percutaneous Left Atrial Appendage Closure

10.21203/rs.3.rs-346548/v1 ◽

2021 ◽

Author(s):

Xiaoye Li ◽

Xiaochun Zhang ◽

Qinchun Jin ◽

Yanli Li ◽

Junbo Ge ◽

...

Keyword(s):

Platelet Aggregation ◽

Platelet Activation ◽

Plasma Levels ◽

Multivariate Regression ◽

Left Atrial Appendage ◽

Platelet Reactivity ◽

Closure Device ◽

Activation Markers ◽

Significant Difference ◽

Operation Procedure

Abstract Background This study was designed to evaluate the platelet reactivity of different antithrombotic regimens under the condition of occluder implantation. Methods A single, prospective cohort study was conducted among patients who received anticoagulation with either dabigatran (N = 33) or rivaroxaban (N = 72) between January 2018 and December 2019. We applied thromboelastogram (TEG) to evaluate platelet aggregation induced with thrombin receptor activating peptide (TRAP) after anticoagulation for 3 months. Plasma coagulation markers mediate platelet activation including TAT, P-selectin, vWF and CD40L were tested by the method of ELISA kit on the day of LAAC and at 3 months after operation procedure. Repeated transesophageal echocardiographic were scheduled to evaluate device related thrombosis (DRT) formation on occluders at 3-month after discharge. Results There was 3(4.2%) in rivaroxaban and 4(12.1%) in dabigatran group experiencing DRT events (OR = 0.315, 95%CI:0.066–1.489, P = 0.129) during follow-ups. The TRAP induced platelet aggregation was higher for patients medication with dabigatran as compared to rivaroxaban group (62.9% vs. 59.7%, P = 0.028*). The plasma levels of TAT, P-selectin, vWF expression was significant higher after 3 months intake of dabigatran compared with that on the day LAAC operation, meanwhile, no significant difference was found in the changes of CD40L plasma levels. After receiving 3 months anticoagulation with rivaroxaban, the expressions of plasma platelet activation of TAT, P-selectin, vWF and CD40L showed no significant changes. We observed significant higher expressions of plasma platelet activation markers for DTR patients in terms of the P-selectin and vWF compared with non-DRT patients. Multivariate regression shwed that anticoagualtion regimen (P = 0.022; OR = 4.366, 95%CI: 0.434–10.839) was an independent predictor for DRT in patients after LAAC operation, while non of the plasma platelet activation included was associated with DRT. Conclusions By avoiding peri-procedure DRT occurrence, it is possible that dabigatran usage might even be reduced, as they had been shown to increase expressions of platelet reactivity.

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Aronia juice consumption prior to half-marathon race can acutely affect platelet activation in recreational runners

Applied Physiology Nutrition and Metabolism ◽

10.1139/apnm-2019-0267 ◽

2020 ◽

Vol 45 (4) ◽

pp. 393-400

Author(s):

Vuk Stevanović ◽

Ana Pantović ◽

Irena Krga ◽

Milica Zeković ◽

Ivana Šarac ◽

...

Keyword(s):

Platelet Aggregation ◽

Platelet Activation ◽

Platelet Function ◽

Repeated Measures ◽

Platelet Reactivity ◽

Activation Parameters ◽

Long Distance ◽

Activation Markers ◽

Marathon Race ◽

Recreational Runners

Long-distance running, especially in non-professional runners, can increase cardiac arrest risk by enhancing platelet activation and aggregation. Polyphenols can exert cardioprotective effects by positively influencing platelet function. This study aimed to examine the acute effects of polyphenol-rich aronia juice consumption, before simulation of a half-marathon race, on platelet activation and aggregation with leukocytes in recreational runners. In this acute crossover study,10 healthy male runners (age 30.8 ± 2.3 years) consumed breakfast with 200 mL of aronia juice or 200 mL of placebo. They warmed-up and ran a simulated half-marathon race (21.1 km). Blood was collected at baseline, and at 15 min, 1 h, and 24 h after the run. All variables were analyzed with 4 (time) × 2 (group) ANOVA with repeated measures on both factors. Results revealed a significant effect of group on platelet activation parameters: P-selectin and GPIIb-IIIa expressions significantly decreased in the aronia group compared with the placebo group (F[1,9] = 10.282, p = 0.011 and F[1,9] = 7.860, p = 0.021, respectively). The effect of time was significant on both platelet aggregation markers: platelet-monocyte and platelet-neutrophil aggregates were significantly lower after the race (F[3,7] = 4.227, p = 0.014 and F[3,7] = 70.065, p = 0.000, respectively), with changes more pronounced in the later. All effects remained when platelets were exposed to an agonist. These results suggest that aronia consumption could counteract the half-marathon race-induced changes in platelet function. Novelty Aronia juice consumption significantly decreased the expression of platelet activation markers but did not affect platelet aggregation. The race itself did significantly reduce platelet-neutrophil aggregation. Aronia juice may serve as a supplement beverage for recreational runners to alleviate enhanced platelet reactivity caused by prolonged running.

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Platelet protein S limits venous but not arterial thrombosis propensity by controlling coagulation in the thrombus

Blood ◽

10.1182/blood.2019003630 ◽

2020 ◽

Vol 135 (22) ◽

pp. 1969-1982 ◽

Cited By ~ 3

Author(s):

Sara Calzavarini ◽

Raja Prince-Eladnani ◽

François Saller ◽

Luca Bologna ◽

Laurent Burnier ◽

...

Keyword(s):

Platelet Activation ◽

Activated Protein C ◽

Vena Cava ◽

Protein S ◽

Limiting Factor ◽

Factor X ◽

Platelet Factor ◽

Shear Rates ◽

Platelet Protein ◽

Factor X Activation

Abstract Anticoagulant protein S (PS) in platelets (PSplt) resembles plasma PS and is released on platelet activation, but its role in thrombosis has not been elucidated. Here we report that inactivation of PSplt expression using the Platelet factor 4 (Pf4)-Cre transgene (Pros1lox/loxPf4-Cre+) in mice promotes thrombus propensity in the vena cava, where shear rates are low, but not in the carotid artery, where shear rates are high. At a low shear rate, PSplt functions as a cofactor for both activated protein C and tissue factor pathway inhibitor, thereby limiting factor X activation and thrombin generation within the growing thrombus and ensuring that highly activated platelets and fibrin remain localized at the injury site. In the presence of high thrombin concentrations, clots from Pros1lox/loxPf4-Cre− mice contract, but not clots from Pros1lox/loxPf4-Cre+ mice, because of highly dense fibrin networks. Thus, PSplt controls platelet activation as well as coagulation in thrombi in large veins, but not in large arteries.

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No Association Between Platelet Function and Hemophilia B Phenotype

Blood ◽

10.1182/blood.v124.21.4994.4994 ◽

2014 ◽

Vol 124 (21) ◽

pp. 4994-4994 ◽

Cited By ~ 1

Author(s):

Roger E.G. Schutgens ◽

Esther R. van Bladel ◽

Kathelijn Fischer ◽

Mark Roest ◽

Rolf Urbanus

Keyword(s):

Platelet Activation ◽

Platelet Reactivity ◽

Adenosine Diphosphate ◽

Hemophilia B ◽

Healthy Controls ◽

Severe Hemophilia ◽

Platelet Activity ◽

Activation Markers ◽

Receptor Associated Protein ◽

The Individual

Abstract Introduction In hemophilia, unravelling the mechanisms behind interindividual variability in phenotype remains a big challenge. Objectives To study platelet activation and platelet responsiveness in relation to hemostatic phenotypes in hemophilia B by 1) comparing hemophilia B patients to healthy controls and 2) relating these to the clinical phenotype of the individual patients with severe hemophilia B. Methods Platelet reactivity was determined in whole blood measuring expression of P-selectin and binding of fibrinogen with FACS analysis after stimulating or inhibiting platelets with concentration series of several (ant-)agonists, including adenosine diphosphate (ADP), convulxin (CVX) and thrombin receptor associated protein (TRAP)and iloprost. Concentration of soluble platelet activation markers (soluble P-selectin, β-Thromboglobulin and RANTES) were measured in platelet poor plasma by ELISA. Markers of platelet activation and responsiveness were compared between healthy controls (n=12), patients with mild/moderate (n=12) or severe hemophilia B (n=19). In severe hemophilia patients, annual FIX consumption/kg was calculated over the last 6 years. Data were analysed with linear regression using SPSS 20. Results Levels of basal platelet activation (both P-selectin and fibrinogen) were equal between controls, mild/moderate and severe hemophilia B (Figure 1). For basal P-selectin expression, the mean area under the curves for were 28.5 (95% CI 23.3-33.6), 33.0(95% CI 24.4-41.6) and 28.4(95% CI 23.9-32.9) respectively (p=0.4). After stimulation with ADP, CVX and TRAP (with and without iloprost), platelet responsiveness was similar in all groups. There was no relation between annual FIX consumption and any marker of platelet activity. For basal P-selectin expression, the beta coefficient was -0.212 (p=0.38)(Figure 2). Conclusion In hemophilia B, platelet activity and responsiveness was similar to healthy controls. In severe hemophilia patients, there was no relation between FIX consumption and platelet activity. Figure 1. Basal P-selectin activity between healthy controls and hemophilia patients Figure 1. Basal P-selectin activity between healthy controls and hemophilia patients Figure 2. Basal P-selectin activity according to FIX consumption in severe hemophilia B Figure 2. Basal P-selectin activity according to FIX consumption in severe hemophilia B Disclosures Schutgens: Pfizer: Research Funding.

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Association of lipoprotein(a) with intrinsic and on-clopidogrel platelet reactivity

Journal of Thrombosis and Thrombolysis ◽

10.1007/s11239-021-02515-2 ◽

2021 ◽

Author(s):

Alexander Kille ◽

Thomas Nührenberg ◽

Kilian Franke ◽

Christian M. Valina ◽

Gregor Leibundgut ◽

...

Keyword(s):

Flow Cytometry ◽

Platelet Activation ◽

Platelet Reactivity ◽

Laboratory Data ◽

Adenosine Diphosphate ◽

Surface Proteins ◽

Activation Markers ◽

Platelet Surface ◽

Lipoprotein A ◽

Artery Disease

AbstractLipoprotein(a) [Lp(a)] is an independent, genetically determined, and causal risk factor for cardiovascular disease. Laboratory data have suggested an interaction of Lp(a) with platelet function, potentially caused by its interaction with platelet receptors. So far, the potential association of Lp(a) with platelet activation and reactivity has not been proven in larger clinical cohorts. This study analyzed intrinsic platelet reactivity before loading with clopidogrel 600 mg and on-treatment platelet reactivity tested 24 h following loading in patients undergoing elective coronary angiography. Platelet reactivity was tested by optical aggregometry following stimulation with collagen or adenosine diphosphate as well as by flow cytometry. Lp(a) levels were directly measured in all patients from fresh samples. The present analysis included 1912 patients. Lp(a) levels ranged between 0 and 332 mg/dl. There was a significant association of rising levels of Lp(a) with a higher prevalence of a history of ischemic heart disease (p < 0.001) and more extensive coronary artery disease (p = 0.001). Results for intrinsic (p = 0.80) and on-clopidogrel platelet reactivity (p = 0.81) did not differ between quartiles of Lp(a) levels. Flow cytometry analyses of expression of different platelet surface proteins (CD41, CD62P or PAC-1) confirmed these findings. Correlation analyses of levels of Lp(a) with any of the tested platelet activation markers did not show any correlation. The present data do not support the hypothesis of an interaction of Lp(a) with platelet reactivity.

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Minimizing Carry-Over Effects After Treatment Failure and Maximizing Therapeutic Outcome

Zeitschrift für Psychologie ◽

10.1027/2151-2604/a000180 ◽

2014 ◽

Vol 222 (3) ◽

pp. 171-178 ◽

Cited By ~ 3

Author(s):

Mareile Hofmann ◽

Nathalie Wrobel ◽

Simon Kessner ◽

Ulrike Bingel

Keyword(s):

Treatment Failure ◽

Human Subjects ◽

Subsequent Treatment ◽

Clinical Samples ◽

Administration Route ◽

Healthy Human ◽

Negative Experiences ◽

Analgesic Treatment ◽

Balanced Design ◽

Carry Over

According to experimental and clinical evidence, the experiences of previous treatments are carried over to different therapeutic approaches and impair the outcome of subsequent treatments. In this behavioral pilot study we used a change in administration route to investigate whether the effect of prior treatment experience on a subsequent treatment depends on the similarity of both treatments. We experimentally induced positive or negative experiences with a topical analgesic treatment in two groups of healthy human subjects. Subsequently, we compared responses to a second, unrelated and systemic analgesic treatment between both the positive and negative group. We found that there was no difference in the analgesic response to the second treatment between the two groups. Our data indicate that a change in administration route might reduce the influence of treatment history and therefore be a way to reduce negative carry-over effects after treatment failure. Future studies will have to validate these findings in a fully balanced design including larger, clinical samples.

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Plasma Thrombospondin as an Indicator of Intravascular Platelet Activation in Patients with Vasculitis

Thrombosis and Haemostasis ◽

10.1055/s-0038-1646003 ◽

1987 ◽

Vol 58 (03) ◽

pp. 850-852 ◽

Cited By ~ 15

Author(s):

M B McCrohan ◽

S W Huang ◽

J W Sleasman ◽

P A Klein ◽

K J Kao

Keyword(s):

Platelet Activation ◽

Plasma Levels ◽

Half Life ◽

Degradation Products ◽

Plasma Concentrations ◽

Primary Source ◽

Positive Correlation ◽

Activation Marker ◽

Fibrin Degradation Products ◽

The Mean

SummaryThe use of plasma thrombospondin (TSP) concentration was investigated as an indicator of intravascular platelet activation. Patients (n = 20) with diseases that have known vasculitis were included in the study. The range and the mean of plasma TSP concentrations of patients with vasculitis were 117 ng/ml to 6500 ng/ml and 791±1412 ng/ml (mean ± SD); the range and the mean of plasma TSP concentrations of control individuals (n = 33) were 13 ng/ml to 137 ng/ml and 59±29 ng/ml. When plasma TSP concentrations were correlated with plasma concentrations of another platelet activation marker, β-thromboglobulin (P-TG), it was found that the TSP concentration inei eased exponentially as the plasma β-TG level rose. A positive correlation between plasma levels of plasma TSP and serum fibrin degradation products was also observed. The results suggest that platelets are the primary source of plasma TSP in patients with various vasculitis and that plasma TSP can be a better indicator than β-TG to assess intravascular platelet activation due to its longer circulation half life.

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