Interplay of Plasmodium falciparum and thrombin in brain endothelial barrier disruption

Avril, Marion; Benjamin, M. S.; Dols, Mary-Margaret; Smith, Joseph D.

doi:10.1038/s41598-019-49530-1

Cited by 24 publications

(46 citation statements)

References 77 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…Behaviour A was as expected and confirms that aPC rescues thrombin induced barrier disruption in HBMEC as seen above in EAhy926 cells. Behaviour B has been reported previously by several investigators using a range of co-culture systems ( Tripathi et al , 2007 ) ( Gillrie et al , 2012 ) ( Avril et al ., 2019 ), with either IE or parasite material affecting barrier integrity. The delayed recovery after thrombin addition was also reported by Avril et al .…”

Section: Resultsmentioning

confidence: 62%

“…The delayed recovery after thrombin addition was also reported by Avril et al . when using schizont-stage IE in their TEER experiments ( Avril et al ., 2019 ). Based on these findings we have tested the compounds for their ability to block both behaviours.…”

Section: Resultsmentioning

confidence: 99%

“…Two mechanisms for the action of cytoadherence on coagulation/inflammation dysregulation have been proposed ( Figure 1 ). The direct binding of the P. falciparum variant surface protein P. falciparum erythrocyte membrane protein 1 (PfEMP1) to EPCR blocks the conversion of PC to aPC, affecting the ability of this host control system to control PAR1 cleavage by thrombin and altering the PAR1 signalling pathway ( Avril et al , 2019 ; Gillrie et al , 2015 ; Kessler et al , 2017 ; Mosnier & Lavstsen, 2016 ; Sampath et al , 2015 ). This mechanism is dependent on the presence of EPCR-binding parasite variants, and these PfEMP1 types are strongly associated with severe malaria ( Mkumbaye et al , 2017 ; Storm et al , 2019 ).…”

Section: Introductionmentioning

confidence: 99%

See 2 more Smart Citations

Testing the effect of PAR1 inhibitors on Plasmodium falciparum-induced loss of endothelial cell barrier function

et al. 2020

View full text Add to dashboard Cite

Background: Sequestration and cytoadherence of Plasmodium falciparum-infected erythrocytes (IE) to microvascular endothelium alters endothelial barrier function and plays a role in the pathogenesis of severe malaria. Binding of IE is mediated by P. falciparum erythrocyte membrane protein 1 (PfEMP1) and the PfEMP1 variants that binds to endothelial protein C receptor (EPCR) have, in particular, been associated with the dysregulation of the coagulation/inflammation pathways in endothelial cells. This has prompted speculation about the role of protease-activated receptor-1 (PAR1) activation and signalling in causing endothelial activation and loss of barrier function in cerebral malaria. Methods: We used a co-culture of primary human brain microvascular endothelial cells (HBMEC) with P. falciparum material, recombinant PfEMP1 or lysates from IE, and measured barrier function by trans endothelial electrical resistance (TEER). A selection of PAR1 inhibitors was tested for their ability to reverse the P. falciparum and thrombin induced decrease in barrier function. Results: An initial screen in the presence of recombinant PfEMP1 identified a few inhibitors that were able to reduce the rapid thrombin-induced barrier disruption even when activated protein C (aPC) was unable to do so. However, PAR1 inhibitors did not rescue the barrier dysfunction after co-culture with IE lysate. Conclusions: The selected PAR1 inhibitors were able to reverse the disruption of barrier function by thrombin but did not reverse the IE lysate induced disruption of barrier function, implicating a different PAR1-independent mechanism. These findings have implications for the design of adjunct therapies to reduce brain swelling in cerebral malaria.

show abstract

Section: Resultsmentioning

confidence: 62%

Section: Resultsmentioning

confidence: 99%

Section: Introductionmentioning

confidence: 99%

See 1 more Smart Citation

Testing the effect of PAR1 inhibitors on Plasmodium falciparum-induced loss of endothelial cell barrier function

et al. 2020

View full text Add to dashboard Cite

show abstract

“…Recently, in vivo trials in a controlled experiment showed a 17.7% increase in the endogenous thrombin generation in humans infected with P. falciparum, presenting a procoagulant state in the early stages of infection and indicating that the coagulation system reacts to infection and may play a role in the parasite lifecycle (Riedl et al 2016). Another study revealed the interaction between iRBC and thrombin in brain microvascular endothelial cell disruption, showing that erythrocytes infected with late-stage parasites induce endothelial cell death and increase permeability due to the action of thrombin and delayed tissue recovery (Avril et al 2019). Therefore, it is possible that iRBCs use the host's coagulation cascade to mediate cytoadhesion processes to the vascular endothelium to prevent spleen cleaning.…”

Section: Introductionmentioning

confidence: 99%

BRET sensors unravel thatPlasmodium falciparumserpentine receptor 12 (PfSR12) increases surface expression of mammalian GPCRs in HEK293 cells

Pereira

Brito

Moraes

et al. 2020

Preprint

View full text Add to dashboard Cite

Malaria causes millions of deaths worldwide and is considered a huge public health problem for underdeveloped countries. The most severe cases of malaria present complications of the host circulatory system, which may cause clogging and rupture of blood vessels, leading to death or important sequelae. Because of the previously suggested role of thrombin and platelet aggregation in Plasmodium falciparum biology, we hypothesized that one of the GPCR-like proteins identified in the genome of the parasite, P. falciparum serpentine receptor 12 (PfSR12), could be a thrombin-activated GPCR. To test this hypothesis we used a series of Bioluminescence and Bioluminescence Resonance Energy Transfer (BRET)-based biosensors to investigate the signaling activity of PfSR12. Using an Obelin based biosensor, thrombin promoted a PfSR12-dependent cytosolic Ca 2+ rise in HEK293 cells. This Ca 2+ mobilization was accompanied by DAG formation and PKC activation as detected using DAG and PKC BRET-based biosensors indicating a Gq/PLC/IP3 signaling pathway. The role of Gq was confirm using Gq/11 knockout HEK293 cells as well as the Gq-selective inhibitor, YM254890. Further investigation revealed that PfSR12 is not itself a thrombin receptor but rather promotes the increase of cell surface expression of an endogenous thrombin receptor. This chaperone-like effect was not selective for thrombin receptors as PfSR12 expression also promoted an increased muscarinic type 3 receptor (M3R)-promoted DAG and PKC responses. This increase response was accompanied by an increase in surface expression of M3R. Our data indicate that PfSR12 acts as a chaperone and increases the expression of several GPCRs resulting in increased responsiveness to various hormones of mammalian cells that could contribute to the deleterious effects of Plasmodium falciparum infection.

show abstract

“…Two mechanisms for the action of cytoadherence on coagulation/ inflammation dysregulation have been proposed (Figure 1). The direct binding of the P. falciparum variant surface protein P. falciparum erythrocyte membrane protein 1 (PfEMP1) to EPCR blocks the conversion of PC to aPC, affecting the ability of this host control system to control PAR1 cleavage by thrombin and altering the PAR1 signalling pathway (Avril et al, 2019;Gillrie et al, 2015;Kessler et al, 2017;Mosnier & Lavstsen, 2016;Sampath et al, 2015). This mechanism is dependent on the presence of EPCR-binding parasite variants, and these PfEMP1 types are strongly associated with severe malaria (Mkumbaye et al, 2017;Storm et al, 2019).…”

Section: Introductionmentioning

confidence: 99%

Testing the effect of PAR1 inhibitors on Plasmodium falciparum-induced loss of endothelial cell barrier function

Storm¹,

Davies²,

Moxon³

et al. 2020

Wellcome Open Res

View full text Add to dashboard Cite

Background: Sequestration and cytoadherence of Plasmodium falciparum-infected erythrocytes (IE) to microvascular endothelium alters endothelial barrier function and plays a role in the pathogenesis of severe malaria. Binding of IE is mediated by P. falciparum erythrocyte membrane protein 1 (PfEMP1) and the PfEMP1 variants that binds to endothelial protein C receptor (EPCR) have, in particular, been associated with the dysregulation of the coagulation/inflammation pathways in endothelial cells. This has prompted speculation about the role of protease-activated receptor-1 (PAR1) activation and signalling in causing endothelial activation and loss of barrier function in cerebral malaria. Methods: We used a co-culture of primary human brain microvascular endothelial cells (HBMEC) with P. falciparum material, recombinant PfEMP1 or lysates from IE, and measured barrier function by trans endothelial electrical resistance (TEER). A selection of PAR1 inhibitors was tested for their ability to reverse the P. falciparum and thrombin induced decrease in barrier function. Results: An initial screen in the presence of recombinant PfEMP1 identified a few inhibitors that were able to reduce the rapid thrombin-induced barrier disruption even when activated protein C (aPC) was unable to do so. However, in the IE lysate co-culture system we identified a mechanism that slowly reduces barrier function and which is insensitive to PAR1 inhibitors. Conclusions: The selected PAR1 inhibitors were able to reverse the disruption of barrier function by thrombin but did not reverse the IE lysate induced disruption of barrier function, implicating a different PAR1-independent mechanism. These findings have implications for the design of adjunct therapies to reduce brain swelling in cerebral malaria.

show abstract

Interplay of Plasmodium falciparum and thrombin in brain endothelial barrier disruption

Cited by 24 publications

References 77 publications

Testing the effect of PAR1 inhibitors on Plasmodium falciparum-induced loss of endothelial cell barrier function

Testing the effect of PAR1 inhibitors on Plasmodium falciparum-induced loss of endothelial cell barrier function

BRET sensors unravel thatPlasmodium falciparumserpentine receptor 12 (PfSR12) increases surface expression of mammalian GPCRs in HEK293 cells

Testing the effect of PAR1 inhibitors on Plasmodium falciparum-induced loss of endothelial cell barrier function

Contact Info

Product

Resources

About