Nephrol Dial Transplant (2008) 23: 2129–2132
doi: 10.1093/ndt/gfn029
Advance Access publication 15 February 2008
Circulating microparticles in renal diseases
Laurent Daniel1,2 , Laetitia Dou3 , Yvon Berland4 , Philippe Lesavre5 , Lise Mecarelli-Halbwachs5 and
Francoise Dignat-George3,6
1
Department of Pathology, CHU Timone-Adultes, 2 UMR 911 INSERM, Université de la Méditerranée, 3 UMR-S 608 INSERM,
Université de la Méditerranée, 4 Department of Nephrology, CHU Conception, Marseille, 5 Department of Nephrology, CHU Necker
and INSERM 507, Paris and 6 Department of Haematology, CHU Conception, Marseille, France
Keywords: atherosclerosis; microparticles; renal failure;
vasculitis
Introduction
Cellular microparticles (MP) are submicrometric fragments
resulting from the remodelling of the plasma membrane in
response to numerous conditions, including activation and
apoptosis [1]. The general consensus is that MP are small
(<1 µm), expose the anionic phospholipid phosphatidylserine (PhtdSer) and express membrane antigens that reflect
their cellular origin. These characteristics discriminate MP
from exosomes, which are smaller (<0.1 µm), originate
from intracellular multivesicular bodies and differ in antigenic composition [2].
MP formation, composition and functions
All cell types shed MP according to an active process
controlling plasma membrane remodelling and antigenic
turnover. Among the mechanisms proposed, disruption of
the natural asymmetric distribution of membrane phospholipids is thought to be an important step explaining the
translocation of PhtdSer to the exoplasmic leaflet before
membrane blebbing and MP shedding. Although calcium
entry, activation of calpains and scramblase activity have
been reported to be important processes [3], the exact mechanisms governing MP formation are not completely understood.
MP phospholipid composition, phenotypes and content
vary according to the cellular origin and the inducer triggering their formation (Table 1). Determination of the cellular
origin of MP relies on the expression of specific antigens.
According to the cell type, their formation occurs following
exposure to various agents, including calcium ionophore,
ATP depletion, lipopolysaccharides, thrombin, cytokines
and autoantibodies (Table 1). Therefore, vesiculation is a
Correspondence and offprint requests to: Laurent Daniel, Hopital
Timone - Anatomo-Pathologie 264 rue st-pierre Marseille 13005, France.
Tel: +334-9138-5531; Fax: +334-9138-4411; E-mail: laurent.daniel
@ap-hm.fr
well-regulated process generating MP that present specific
features, with significant implications on their functional
activity.
Indeed, MP behave as vectors of bioactive molecules
able to disseminate biological information in the vascular compartment. Due to the expression of both membrane
PhtdSer and functional tissue factor (TF), MP are catalytic
procoagulant surfaces involved in thrombogenesis. They
also harbour inflammatory components (LpA, IL-1 and
chemokine receptor CCR5) [4,5], growth factors (TGF-beta
and VEGF) and proteases (uPA and MMP) that are related
to their involvement in inflammation, immune response,
angiogenesis and cancer [6–8].
MP measurement and variations in atherosclerotic
vascular diseases
Different methodologies, which were reported in a forum
[9], are available for MP determination. Antibody-capture
ELISA and flow cytometry rely on the antigenic composition of MP and allow them to be enumerated according to
their cellular origin. Besides, functional assays measuring
MP-associated procoagulant activity are based on PhtdSer
and TF expression. Finally, other assays combine ELISA
capture on annexin or antibody and determination of procoagulant activity of MP.
MP are detectable in the peripheral blood of healthy
volunteers. Elevated levels of circulating platelet-,
monocyte- or endothelial-derived MP have been reported in
cardiovascular disorders such as diabetes [10], acute coronary syndromes, hypertension [11], metabolic syndrome,
heart transplantation and pulmonary or venous embolism
[12]. It is now obvious that MP levels are associated with
cardiovascular risk factors and most often correlate with
disease severity and clinical outcome [1].
MP in renal diseases
Elevated levels of MP have been detected throughout the
entire process of vascular damage associated with renal
diseases.
During renal diseases with acute vascular lesions, such
as Wegener granulomatosis or micro-polyangiitis, MP
originating from platelets and neutrophils increase
C The Author [2008]. Published by Oxford University Press on behalf of ERA-EDTA. All rights reserved.
For Permissions, please e-mail: [email protected]
2130
Nephrol Dial Transplant (2008) 23: Editorial Comments
Table 1. MP cell origin and antigenic features
Cell origin
Antigens
Vesiculation agents
References
Erythrocytes
Monocytes
Granulocytes
Lymphocytes
Platelets
Endothelium
CD235(a)
CD14
CD66b
CD4, CD8 and CD3
CD41, CD42 and CD61
CD31, CD51, CD105, CD146 and CD144
Ionophore A23187, acid pH and ATP depletion
LPS and phorbol esters
LPS and phorbol esters
LPS and phorbol esters
ADP, collagen, thrombin and A23187
Complement, thrombin, autoantibodies and cytokines
[24]
[25]
[26]
[27]
[28]
[29]
dramatically. These levels, which were significantly higher
than those reported in chronic vasculitis, may be considered
as markers of disease activity [13]. In children with acute
vasculitis, increased levels of endothelial MP (EMP) correlated with the Birmingham Vasculitis Activity Score and
the acute-phase reactant levels, suggesting that they could
be used as diagnostic tool in the context of febrile diseases
[14].
A vesiculation process, reflecting endothelial injury and
platelet activation, is also a feature of vascular disorders
associated with immune-mediated renal lesions. In agreement, high platelet MP (PMP) levels are observed in microangiopathies, whereas EMP vary as lactate dehydrogenase levels over the course of acute phase. Elevation of
EMP has also been reported in antiphospholipid syndrome,
where they strongly correlate with procoagulant activity of
lupus anticoagulant [15].
MP levels are increased during chronic renal failure
(CRF), suggesting that vesiculation may participate in
thrombogenesis and compensation for the bleeding tendency in CRF. Elevated PMP counts have been reported in
CRF patients (pre-dialyzed, under haemodialysis and under
ambulatory peritoneal dialysis), with significantly higher
levels in patients with thrombotic events. The existence of
an arteriovenous fistula did not affect PMP count [16]. It
is well established that CRF patients display accelerated
atherosclerosis related to endothelial dysfunction. Hence,
high EMP levels, detected in uraemic patients in the absence
of a clinical history of vascular disease, may constitute an
early indicator of vascular injury [17].
Diabetes is a confounding factor during CRF, but PMP
levels are equivalent during end-stage CRF whatever be the
initial diseases, i.e. diabetic nephropathies or others. Additionally, the increase in EMP levels in series remains significant after exclusion of diabetic patients. Finally, among
diabetic patients, PMP and EMP levels are higher in those
presenting nephropathies [18].
High PMP levels are clearly a risk factor for thrombotic
events in non-CRF patients. Although it is well known that
the main drugs used for cardiovascular diseases and CRF
are able to decrease MP number and procoagulant activity, one should also keep in mind that they have not been
evaluated in the main series. This is particularly true for
statins [19] and nifedipine [20], which decrease, respectively, leukocyte-platelet MP and PMP.
In patients with end-stage CRF, platelet, erythrocyte,
and endothelial MP are increased [21]. However, only EMP
levels correlate with a loss of flow-mediated dilatation and
Fig. 1. This schema summarizes the concept that MP are both causes
and consequences of vascular dysfunction. Pl, platelets; PMN, polymorphonuclear cells; Mo, monocytes; MP, microparticles; AGEs, advanced
glycation end products.
increased aortic pulse wave velocity, suggesting that they
are highly associated with arterial and endothelial dysfunction in end-stage CRF [22].
MP are both causes and consequences of vascular
dysfunction (Figure 1)
In acute vascular lesions, numerous in vitro studies have
accounted for a direct role of MP in disease progression.
Renal microvessel cells exposed to plasma of patients with
thombotic thrombopenic purpura shed prothrombotic MP
expressing von Willebrand Factor (VWF) that can spread
into the circulation of the ultralarge VWF multimers resulting from ADAMTS-13 deficiency. In immune-mediated
acquired renal disease, MP bear procoagulant activity detected in patients with antiphospholipid syndrome. MP may
be pathogenic when they bear proteinase 3, as in antineutrophil cytoplasmic antibody (ANCA)-vasculitis [15].
In patients with CRF, EMP levels may reflect subclinical lesions because their levels correlate with arterial stiffness and vasodilatation changes [21]. In this context, MP
could also participate in the progression of vascular lesions
because a decrease in endothelial nitric oxide is detected
Nephrol Dial Transplant (2008) 23: Editorial Comments
in vitro when EMP from uraemic patients are added on
rodent aorta rings in culture.
Besides endothelial-dependent vasodilatation changes,
other vascular abnormalities reflected by the alteration of
VWF and thrombomodulin concentrations have been correlated with MP levels in CRF. Increased PMP levels may
be a crucial step for arteriosclerosis, because PMP promote chemokine Rantes deposits on endothelial cells and
favour leukocyte recruitment, particularly, in the context of
pre-existing atherosclerosis as in CRF [23].
In patients with CRF, one could speculate that the initial stimuli that lead to MP generation could result from a
release of LPS, AGEs, proinflammatory cytokines (TNFα
and IL-1) or oxidized LDL, reflecting the oxidant stress.
Uraemic toxins might also be involved because para-cresol
and indoxyl sulphate induce vesiculation by HUVEC (human umbilical vein endothelial cell) [17].
Haemodialysis treatment is among the stimuli inducing
MP generation. A dramatic increase in PMP is observed
at the end of a dialysis session. This is probably explained
by the membrane-induced complement activation and biological effects of extracorporeal dialysers. Results are not
similar for EMP. As dialysis restores viscosity, which is reflected by haematocrit, it also restores laminar shear stress
and thus may decrease EMP levels, because it is well known
that a lower local shear stress is associated with endothelial
apoptosis and MP release [21]. The complement is another
factor of vesiculation, since a membrane attack complex is
formed during the first minutes of dialysis. Nevertheless,
the membrane type (synthetic or celluloid) has no significant effect on circulating MP levels [13]. Another cause
for MP release is the endotoxins present in the dialysate
fluid.
Conclusion
MP behave as effectors that play a deleterious role in renal
diseases. They also represent novel biomarkers that are useful to appreciate cardiovascular risk associated with CRF
and sometimes disease activity. The pharmacological control of MP is the next challenge in the control of CRFvascular complications.
Conflict of interest statement. None declared.
References
1. Freyssinet JM, Dignat-George F. More on: measuring circulating cellderived microparticles. J Thromb Haemost 2005; 3: 613–614
2. Heijnen HF, Schiel AE, Fijnheer R et al. Activated platelets release
two types of membrane vesicles: microvesicles by surface shedding
and exosomes derived from exocytosis of multivesicular bodies and
alpha-granules. Blood 1999; 94: 3791–3799
3. Simak J, Gelderman MP. Cell membrane microparticles in blood and
blood products: potentially pathogenic agents and diagnostic markers.
Transfus Med Rev 2006; 20: 1–26
4. Mack M, Kleinschmidt A, Bruhl H et al. Transfer of the chemokine
receptor CCR5 between cells by membrane-derived microparticles: a
mechanism for cellular human immunodeficiency virus 1 infection.
Nat Med 2000; 6: 769–775
2131
5. MacKenzie A, Wilson HL, Kiss-Toth E et al. Rapid secretion of
interleukin-1beta by microvesicle shedding. Immunity 2001; 15: 825–
835
6. Gasser O, Schifferli JA. Activated polymorphonuclear neutrophils
disseminate anti-inflammatory microparticles by ectocytosis. Blood
2004; 104: 2543–2548
7. Morel O, Toti F, Hugel B et al. Procoagulant microparticles: disrupting
the vascular homeostasis equation? Arterioscler Thromb Vasc Biol
2006; 26: 2594–2604
8. Mezentsev A, Merks RM, O’Riordan E et al. Endothelial microparticles affect angiogenesis in vitro: role of oxidative stress. Am J Physiol
Heart Circ Physiol 2005; 289: 1106–1114
9. Jy W, Horstman LL, Jimenez JJ et al. Measuring circulating
cell-derived microparticles. J Thromb Haemost 2004; 2: 1842–
1851
10. Sabatier F, Darmon P, Hugel B et al. Type 1 and type 2 diabetic
patients display different patterns of cellular microparticles. Diabetes
2002; 51: 2840–2845
11. Preston RA, Jy W, Jimenez JJ et al. Effects of severe hypertension on
endothelial and platelet microparticles. Hypertension 2003; 4: 211–
217
12. Boulanger CM, Amabile N, Tedgui A. Circulating microparticles:
a potential prognostic marker for atherosclerotic vascular disease.
Hypertension 2006; 48: 180–186
13. Daniel L, Fakhouri F, Joly D et al. Increase of circulating neutrophil
and platelet microparticles during acute vasculitis and hemodialysis.
Kidney Int 2006; 69: 1416–1423
14. Brogan PA, Shah V, Brachet C et al. Endothelial and platelet microparticles in vasculitis of the young. Arthritis Rheum 2004; 50:
927–936
15. Dignat-George F, Camoin-Jau L, Sabatier F et al. Endothelial microparticles: a potential contribution to the thrombotic complications
of the antiphospholipid syndrome. J Thromb Haemost 2004; 91: 667–
673
16. Ando M, Iwata A, Ozeki Y et al. Circulating platelet-derived microparticles with procoagulant activity may be a potential cause
of thrombosis in uremic patients. Kidney Int 2002; 62: 1757–
1763
17. Faure V, Dou L, Sabatier F et al. Elevation of circulating endothelial microparticles in patients with chronic renal failure. J Thromb
Haemost 2006; 4: 566–573
18. Omoto S, Nomura S, Shouzu A et al. Detection of monocyte-derived
microparticles in patients with Type II diabetes mellitus. Diabetologia
2002; 45: 550–555
19. Nomura S, Shouzu A, Omoto S et al. Losartan and simvastatin inhibit
platelet activation in hypertensive patients. J Thromb Thrombolysis
2004; 18: 177–185
20. Nomura S, Shouzu A, Omoto S et al. Long-term treatment with
nifedipine modulates procoagulant marker and C-C chemokine in hypertensive patients with type 2 diabetes mellitus. Thromb Res 2005;
115: 277–285
21. Amabile N, Guerin AP, Leroyer A et al. Circulating endothelial
microparticles are associated with vascular dysfunction in patients
with end-stage renal failure. J Am Soc Nephrol 2005; 16: 3381–
3388
22. Boulanger CM, Amabile N, Guerin AP et al. In vivo shear stress
determines circulating levels of endothelial microparticles in endstage renal disease. Hypertension 2007; 49: 902–908
23. Mause SF, von Hundelshausen P, Zernecke A et al. Platelet microparticles: a transcellular delivery system for RANTES promoting monocyte recruitment on endothelium. Arterioscler Thromb Vasc Biol 2005;
25: 1512–1518
24. Hugel B, Socie G, Vu T et al. Elevated levels of circulating procoagulant microparticles in patients with paroxysmal nocturnal hemoglobinuria and aplastic anemia. Blood 1999; 93: 3451–3456
25. Satta N, Toti F, Feugeas O et al. Monocyte vesiculation is a possible
mechanism for dissemination of membrane-associated procoagulant
activities and adhesion molecules after stimulation by lipopolysaccharide. J Immunol 1994; 153: 3245–3255
2132
26. Watanabe J, Marathe GK, Neilsen PO et al. Endotoxins stimulate
neutrophil adhesion followed by synthesis and release of plateletactivating factor in microparticles. J Biol Chem 2003; 278: 33161–
33168
27. Martin S, Tesse A, Hugel B et al. Shed membrane particles from
T lymphocytes impair endothelial function and regulate endothelial
protein expression. Circulation 2004; 109: 1653–1659
Nephrol Dial Transplant (2008) 23: Editorial Comments
28. Combes V, Dignat-George F, Mutin M et al. A new flow cytometry method of platelet-derived microvesicle quantitation in plasma. J
Thromb Haemost 1997; 77: 220
29. Combes V, Simon AC, Grau GE et al. In vitro generation of
endothelial microparticles and possible prothrombotic activity in
patients with lupus anticoagulant. J Clin Invest 1999; 104: 93–
102
Received for publication: 25.6.07
Accepted in revised form: 16.1.08