close

Вход

Забыли?

вход по аккаунту

?

The prototypic tissue pentraxin PTX3 in contrast to the short pentraxin serum amyloid P inhibits phagocytosis of late apoptotic neutrophils by macrophages.

код для вставкиСкачать
ARTHRITIS & RHEUMATISM
Vol. 50, No. 8, August 2004, pp 2667–2674
DOI 10.1002/art.20370
© 2004, American College of Rheumatology
The Prototypic Tissue Pentraxin PTX3, in Contrast to the
Short Pentraxin Serum Amyloid P, Inhibits Phagocytosis of
Late Apoptotic Neutrophils by Macrophages
André P. van Rossum,1 Fausto Fazzini,2 Pieter C. Limburg,1 Angelo A. Manfredi,2
Patrizia Rovere-Querini,2 Alberto Mantovani,3 and Cees G. M. Kallenberg1
Results. SAP and complement were both necessary for effective in vitro phagocytosis. In contrast,
PTX3 inhibited phagocytosis in a dose-dependent manner, from 11% inhibition at 6.25 ␮g/ml to almost
complete inhibition at 100 ␮g/ml. Furthermore, PTX3
partly affected binding of apoptotic PMNs to macrophages.
Conclusion. PTX3, in contrast to SAP and complement, inhibits phagocytosis of late apoptotic PMNs
by monocyte-derived macrophages in a dose-dependent
manner. Therefore, PTX3 can play a role in the development of leukocytoclasia by affecting the clearance of
apoptotic PMNs, thereby inducing their accumulation
in the vessel wall.
Objective. Phagocytosis of apoptotic cells can be
facilitated by complement components and short pentraxins, such as serum amyloid P (SAP). In contrast, the
long pentraxin PTX3 was shown to inhibit phagocytosis
of apoptotic Jurkat cells by dendritic cells and to bind
late apoptotic polymorphonuclear leukocytes (PMNs).
Recently, levels of the pentraxin PTX3 were shown to
parallel disease activity in small-vessel vasculitis, which
is often characterized by leukocytoclasia, a persistence
of leukocyte remnants in the vessel wall. We undertook
this study to test our hypothesis that PTX3 inhibits
phagocytosis of late apoptotic PMNs by macrophages,
thereby leading to their accumulation in the vessel wall.
Methods. Macrophages were allowed to phagocytose late apoptotic or secondary necrotic PMNs that
were incubated with or without PTX3 for 30 minutes
prior to phagocytosis. Phagocytosis was allowed to occur
in the presence of 30% normal human serum with or
without SAP and with or without depletion of complement. To discriminate between an inhibitory effect of
PTX3 on binding and the internalization of apoptotic
PMNs into macrophages, internalization was blocked by
cytochalasin B.
Pentraxins can be divided into two structural
classes: the classic short pentraxins, such as C-reactive
protein (CRP) and serum amyloid P (SAP), with monomeric molecular weight of ⬃25 kd, and the recently
described long pentraxins, with molecular weights of
40–50 kd (for review, see ref. 1). Recently, the long
pentraxin PTX3 was identified as a novel acute-phase
reactant in active vasculitis. Fazzini et al showed that
PTX3 is produced at sites of inflammation, and levels of
PTX3 can be used as an independent laboratory indicator for disease activity in small-vessel vasculitis (2).
Serum levels of PTX3 only partially corresponded to
levels of CRP. Furthermore, in the same study, these
investigators showed that activated endothelial cells
produce PTX3 at sites of active vasculitis, in contrast to
hepatically produced CRP.
Serum concentrations of CRP can increase up to
1,000-fold within a few hours during the acute-phase
response (3). In mice, another short pentraxin, SAP, also
responds as an acute-phase reactant (3). The function of
peripherally produced PTX3 is currently unclear. Re-
Supported by the Ministero della Salute, the European
Union, and the Associazione Italiana per la Ricerca sul Cancro.
1
André P. van Rossum, MSc, Pieter C. Limburg, PhD, Cees
G. M. Kallenberg, MD, PhD: University Hospital Groningen, Groningen, The Netherlands; 2Fausto Fazzini, MD, Angelo A. Manfredi,
MD, Patrizia Rovere-Querini, MD, PhD: H. San Raffaele Scientific
Institute, Milan, Italy; 3Alberto Mantovani, MD: Instituto di Ricerche
Farmacologiche “Mario Negri” and Università, Milan, Italy.
Mr. van Rossum and Dr. Fazzini contributed equally to this
work.
Address correspondence and reprint requests to Cees G. M.
Kallenberg, MD, PhD, Department of Internal Medicine, University
Hospital Groningen, Hanzeplein 1, 9713 GZ Groningen, The Netherlands. E-mail: c.g.m.kallenberg@int.azg.nl.
Submitted for publication June 30, 2003; accepted in revised
form March 29, 2004.
2667
2668
VAN ROSSUM ET AL
cent studies with the pentraxins SAP and CRP have
demonstrated an important facilitating role of these
molecules in phagocytosis of apoptotic cells (4). PTX3
was shown to be involved in phagocytosis as well. Rovere
et al reported that PTX3 specifically binds to apoptotic
Jurkat cells and subsequently inhibits their phagocytosis
by dendritic cells (DCs) (5). Additionally, they showed
that late apoptotic polymorphonuclear leukocytes
(PMNs) were able to bind PTX3. In view of the persistence of late apoptotic or secondary necrotic PMNs in
active leukocytoclastic vasculitis (6), and given the association between vasculitis disease activity and serum
PTX3 levels (2), we hypothesized that PTX3, produced
locally by activated endothelial cells, might play a role in
the persistence of late apoptotic or secondary necrotic
PMNs in vasculitic lesions.
The histopathologic features of small-vessel vasculitis are often designated leukocytoclastic vasculitis
(6). Leukocytoclasia (i.e., the accumulation of unscavenged dead neutrophils within the vessel wall) is normally an uncommon phenomenon. Leukocytoclastic lesions are primarily found in the skin, but other organs
may be involved as well (7). In small-vessel vasculitis,
levels of proinflammatory cytokines, such as tumor
necrosis factor ␣ (TNF␣) and interleukin-1␤ (IL-1␤),
are elevated (8). TNF␣ and IL-1␤ can activate endothelial cells, resulting in adhesion and migration of neutrophils. Furthermore, it has been shown that proinflammatory signals induce the production of PTX3 in
endothelial cells, and PTX3 was shown to be expressed
in endothelial cells and infiltrating leukocytes at sites of
active vasculitis (2,9).
In the present study, we investigated whether
PTX3, in contrast to SAP and complement, inhibits the
phagocytosis of late apoptotic PMNs by macrophages.
Such a finding would explain the phenomenon of leukocytoclasia in small-vessel vasculitis.
MATERIALS AND METHODS
Materials. All chemicals used were from Sigma (St.
Louis, MO) unless indicated otherwise. Anticoagulant tubes
were from BD Vacutainer Systems (Plymouth, UK). Hanks’
balanced salt solution (HBSS) and gentamycin were purchased
from Gibco Life Technologies (Paisley, UK). RPMI 1640 and
fetal calf serum (FCS) were from BioWhittaker Europe (Verviers, Belgium), and culture plates were from Costar (Badhoevedorp, The Netherlands). Human PTX3 was purified from
Chinese hamster ovary cells stably and constitutively expressing the protein, as described by Bottazzi et al (10).
Isolation and culture of human neutrophils. Neutrophils were isolated from blood of healthy human volunteers by
Polymorphoprep (Nycomed, Oslo, Norway) density-gradient
centrifugation. EDTA-anticoagulated blood (5 ml) was carefully layered over 5 ml of solution and centrifuged at 500g for
30 minutes, and the middle band was harvested. Red blood
cells were lysed twice by mixing the cells with 6 ml NH4Cl
solution, incubation for 10 minutes on ice, and centrifugation
(at 1,200g for 3 minutes). Subsequently, neutrophils were
washed in HBSS without calcium and magnesium and centrifuged at 1,200g for 3 minutes. Finally, neutrophils (1 ⫻ 106/ml)
were reconstituted in RPMI 1640 supplemented with gentamycin (60 ␮g/ml) and 5% FCS in 6-well plates and aged for 72
hours at 37°C in 5% CO2 to yield late apoptotic or secondary
necrotic PMNs. Apoptosis and necrosis were measured by
annexin V and propidium iodide staining. For staining, 99 ␮l
binding buffer (10 mM HEPES [pH 7.4], 140 mM NaCl, 5 mM
CaCl2), 10 ␮l propidium iodide (10 ␮g/ml; Molecular Probes,
Leiden, The Netherlands), and 1 ␮ l of fluorescein
isothiocyanate–labeled annexin V (Nexins Research, Hoeven,
The Netherlands) diluted 1:10 were added to 1 ⫻ 106 PMNs of
a 100-␮l cell suspension. Immediately after incubation for 10
minutes on ice in the dark, immunofluorescence analysis was
performed on an Epics-Elite fluorescence-activated cell sorter
equipped with a gated amplifier (Coulter Electronics, Mijdrecht, The Netherlands).
Macrophage culture. Peripheral blood mononuclear
cells were isolated by Lymphoprep (Nycomed) densitygradient centrifugation from citrated blood. Healthy controls
served as donors. Cells were suspended in medium containing
RPMI 1640, gentamycin, and 2% pooled normal human serum
(NHS) at a concentration of 1 ⫻ 106/ml. Plastic coverslips
(13-mm diameter; Nunc, Roskilde, Denmark) were placed in a
16-mm–diameter 24-well plate (Costar, Schiphol, The Netherlands). Cell suspension (0.5 ml) was seeded in every well, and
monocytes were subsequently allowed to differentiate into
macrophages during 7 days at 37°C in a 5% CO2 atmosphere.
On days 2 and 5, the medium was supplemented with 0.5 ml
fresh medium.
Phagocytosis assay and scoring. Coverslips with adherent monocyte-derived macrophages were washed with RPMI
1640 containing 1% NHS to remove nonadherent cells and
were transferred into 24-well plates. Late apoptotic PMNs
were incubated for 30 minutes with various concentrations of
PTX3 (0, 3.125, 6.25, 12.5, 25, 50, and 100 ␮g/ml) and were
resuspended in RPMI 1640 containing 30% NHS. Next, the
PMN suspensions (0.3 ml/well) containing 5 ⫻ 105 cells were
added to the 24-well plates containing monocyte-derived macrophages (5 ⫻ 104/well), and cell interaction was allowed for 30
minutes at 37°C in 5% CO2. Cell interaction was also allowed
to occur in SAP-depleted and complement-inactivated serum.
SAP-depleted serum was made by passing NHS through an
agarose column enriched with high-electroendosmosis agarose
(lot no. AG 0493; FMC Bioproducts, Rockland, ME), as
described previously (4). Complement-inactivated serum was
made by heating NHS at 56°C for 30 minutes. Subsequently,
coverslips were washed with 0.4% human serum albumin to
remove nonphagocytosed cells.
Scoring of phagocytosis was done as described (4,11).
Briefly, macrophages were flattened by centrifugation at 25g
for 10 minutes and air-dried. Cells were fixed in ethanol and
stained for myeloperoxidase (MPO) as a marker for ingested
PMNs. To this end, samples were incubated for 30 minutes
with an anti-MPO monoclonal antibody (266.6K2; IQProducts,
PTX3 INHIBITS MACROPHAGE PHAGOCYTOSIS OF APOPTOTIC NEUTROPHILS
2669
Figure 1. Representative dot plots of the forward scatter/side scatter (FSC/SSC; left panels) and apoptotic state
(right panels) of polymorphonuclear leukocytes (PMNs) aged for 72 hours. A, Ninety-four percent of freshly
isolated PMNs are negative for annexin V–fluorescein isothiocyanate (FITC) and propidium iodide (PI) staining.
B, Eighty-two percent of PMNs aged for 72 hours are late apoptotic or secondary necrotic as demonstrated by
staining with annexin V–FITC and PI. Additionally, PMNs aged for 72 hours are shifted to the lower left corner
in the FSC/SSC dot plot, indicating late apoptosis or secondary necrosis.
Groningen, The Netherlands), washed 3 times with phosphate
buffered saline, and subsequently incubated with horseradish
peroxidase–conjugated goat anti-mouse antibody (Dako,
Glostrup, Denmark). Dilutions of antibodies were made according to the manufacturers’ protocols. Cells were washed
and allowed to react with diaminobenzidine and H2O2. Finally,
nuclear staining of monocyte-derived macrophages was performed with hematoxylin (Merck, Darmstadt, Germany).
Preparations were scored at 40⫻ magnification by regular light
microscopy, and phagocytosis was assessed by counting the
number of ingested PMNs per individual macrophage per total
of 100 macrophages (phagocytosis index). Only PMNs clearly
within the perimeter of the macrophage were counted.
Assessment of binding. Cytochalasin B (Sigma, Zwijndrecht, The Netherlands) was used to block internalization
(but not binding) of apoptotic cells and was added to the
24-well plates with coverslip-adherent monocyte-derived macrophages (5 ⫻ 104/well) for 30 minutes prior to interaction with
late apoptotic neutrophils. Monocyte-derived macrophages
were allowed to interact with apoptotic PMNs for 30 minutes
at 37°C in 5% CO2 in the presence of cytochalasin B (24
␮g/ml). Scoring was done as described above, except that
binding was scored by counting the number of bound PMNs
per individual macrophage per total of 100 monocyte-derived
macrophages.
Statistical analysis. Results are expressed as the
mean ⫾ SEM of the number of independent experiments.
Statistical analysis was performed using Student’s unpaired
t-test and GraphPad Prism, version 3.0 (GraphPad Software,
San Diego, CA).
RESULTS
We generated late apoptotic or secondary necrotic PMNs by aging for 72 hours, since PTX3 specifically binds to late apoptotic PMNs (5). Fluorescenceactivated cell sorting analysis showed that a mean ⫾
SEM 82.0 ⫾ 5.2% of cells were positive for annexin V
and propidium iodide (Figure 1).
Phagocytosis of late apoptotic PMNs by
monocyte-derived macrophages in 30% NHS showed a
mean ⫾ SEM phagocytosis index of 45.1 ⫾ 1.2% (Figure
2670
VAN ROSSUM ET AL
Figure 2. Inhibitory effect of PTX3 on the phagocytosis of late
apoptotic polymorphonuclear leukocytes (PMNs) by monocytederived macrophages. A, Phagocytosis of late apoptotic PMNs by
monocyte-derived macrophages. PMNs were stained by immunocytochemistry using peroxidase-conjugated antibodies to myeloperoxidase,
a neutrophil-specific marker. Nuclear staining of monocyte-derived
macrophages was performed with hematoxylin (original magnification
⫻ 40). B, Effect of serum amyloid P (SAP), PTX3, and complement on
the phagocytosis of late apoptotic PMNs by monocyte-derived macrophages. PTX3 (100 ␮g/ml) was added to PMNs for 30 minutes prior to
phagocytosis. Subsequently, PMNs were allowed to interact with
monocyte-derived macrophages for 30 minutes in 30% normal human
serum (NHS). Phagocytosis was scored by counting the number of
ingested PMNs per individual macrophage per total of 100 macrophages (phagocytosis index). Depletion of SAP from NHS resulted in
a decrease in the phagocytosis index (P ⬍ 0.0001). Inactivation of
complement in NHS also resulted in decreased phagocytosis (P ⬍
0.0001). PTX3 almost completely inhibited phagocytosis (P ⬍ 0.0001).
C, Dose-dependent inhibitory effect of PTX3 on the phagocytosis of
late apoptotic PMNs by monocyte-derived macrophages. Various
concentrations of PTX3 were added to PMNs 30 minutes prior to
phagocytosis. Results are expressed as the mean ⫾ SEM of at least 3
independent experiments. Color figure can be viewed in the online
issue, which is available at http://www.arthritisrheum.org.
2). Phagocytosis was shown to be complement dependent and partially SAP dependent. Inactivation of complement resulted in a decrease in the phagocytosis index
from 45.1 ⫾ 1.2% to 3.3 ⫾ 1.2% (P ⬍ 0.0001). Depletion
of SAP resulted in a ⬎50% decrease in the phagocytosis
index to 21.8 ⫾ 2.1% (P ⬍ 0.0001) (Figure 2B).
In order to evaluate the effects of PTX3 on
phagocytosis, late apoptotic PMNs were incubated for
30 minutes at room temperature with various concen-
trations of PTX3 in the presence of 30% NHS. Subsequently, we assayed the phagocytosis of PTX3-incubated
PMNs. Incubation of late apoptotic PMNs with 100
␮g/ml PTX3 resulted in a significant decrease in the
phagocytosis index to 3.6 ⫾ 0.8% (Figure 2). The
inhibitory effect of PTX3 on phagocytosis of late apoptotic PMNs was dose dependent (Figure 2C).
Next, to investigate whether the inhibitory effect
of PTX3 was due to a defect in binding of late apoptotic
PTX3 INHIBITS MACROPHAGE PHAGOCYTOSIS OF APOPTOTIC NEUTROPHILS
2671
Figure 3. Inhibitory effect of PTX3 on binding of late apoptotic PMNs. A, Immunohistochemical staining for
binding of late apoptotic PMNs to monocyte-derived macrophages. Cytochalasin B (Cyt. B; 24 ␮g/ml) was added
for 30 minutes prior to interaction with PMNs. PMNs were allowed to bind to cytochalasin B–incubated
macrophages for 30 minutes in 30% NHS. Arrows indicate PMNs bound to monocyte-derived macrophages
(original magnification ⫻ 40). PTX3 (50 ␮g/ml) was added to late apoptotic PMNs for 30 minutes prior to
interaction. Cells were allowed to interact for 30 minutes at 37°C in 5% CO2. B, Phagocytosis or C, binding was
scored by counting the number of ingested or bound PMNs, respectively, per individual macrophage per total of
100 macrophages. Results are expressed as the mean and SEM of at least 3 independent experiments. See Figure
2 for other definitions. Color figure can be viewed in the online issue, which is available at http://
www.arthritisrheum.org.
PMNs, we incubated macrophages with cytochalasin B.
Cytochalasin B–treated cells are incapable of ingesting
particles, but they can still bind particles to membrane
receptors (12). Cytochalasin B (24 ␮g/ml) almost completely disrupted internalization, whereas binding was
still visible (Figure 3). When PMNs incubated with
PTX3 (50 ␮g/ml) were allowed to interact with cytochalasin B–treated monocyte-derived macrophages, binding
was significantly decreased from 76.5 ⫾ 1.5% to 37 ⫾
2.0% (P ⬍ 0.004) (Figure 3C).
DISCUSSION
Apoptotic cells are specifically recognized and
rapidly engulfed by phagocytic cells such as macrophages and DCs. The mechanisms of recognition and
2672
removal are complex and incompletely understood. Apoptosis results in a variety of surface changes, such as
exposure of phosphatidylserine on the outer membrane
of apoptotic cells. In addition, carbohydrates such as
fucose and N-acetylglucosamine are increasingly expressed during apoptosis (13,14). Subsequently, collectins and collectin-like molecules can bind to these newly
expressed molecules (15–18). The collectin-like component of complement C1q has been shown to be involved
in apoptotic cell recognition (17,18). C1q can opsonize
apoptotic cells and interact with complement receptors
such as CR3 and CR4 (19). C1q is thought to play an
important role in phagocytosis. Macrophages from C1qdeficient mice have shown a reduced capacity to phagocytose apoptotic thymocytes (19,20). Binding of complement is a rather late event during apoptotic cell death
and is an immediate early feature of necrotic cells.
Therefore, complement might serve as an opsonin for
late apoptotic or secondary necrotic cells that have
escaped normal clearing mechanisms (21). Binding to
apoptotic cells has also been demonstrated for the
pentraxins (5,15,22). The short pentraxins SAP and CRP
can bind to apoptotic and necrotic cells, and they can
facilitate phagocytosis, possibly by interaction with Fc␥
receptors (Fc␥R) (23).
Recently, Bijl et al demonstrated that SAP binds
to late apoptotic Jurkat cells and facilitates their phagocytosis by monocyte-derived macrophages (4). In the
present study, we demonstrated that SAP also facilitates
phagocytosis of late apoptotic PMNs by monocytederived macrophages, since depletion of SAP resulted in
a ⬎50% decrease in phagocytosis. Phagocytosis of late
apoptotic PMNs was shown to be complement dependent as well. The pentraxin PTX3 also appeared to be
involved in phagocytosis (5,24). Rovere et al (5) demonstrated that PTX3 binds specifically to apoptotic cells
and inhibits phagocytosis of apoptotic Jurkat cells by
DCs. Binding of PTX3 to apoptotic Jurkat cells was dose
dependent and saturable. Furthermore, Rovere et al
showed that only late apoptotic neutrophils bind PTX3.
For that reason, we generated late apoptotic or secondary necrotic PMNs by aging for 72 hours. PMNs aged for
72 hours stained positive with annexin V and propidium
iodide.
PTX3 proved to inhibit phagocytosis of late apoptotic PMNs by monocyte-derived macrophages. This
inhibition was dose dependent. To investigate whether
PTX3 interfered with the opsonizing effects of SAP,
SAP-depleted serum was used. In the presence of SAPdepleted serum, PTX3 still inhibited phagocytosis of late
apoptotic PMNs by macrophages. To determine whether
VAN ROSSUM ET AL
this was due to a disturbance in binding of apoptotic
cells, we preincubated macrophages with cytochalasin B,
which interferes with membrane dynamics and thereby
hampers internalization (12). Cytochalasin B–treated
macrophages did bind apoptotic PMNs, whereas internalization was almost completely blocked. When PTX3coated PMNs were added to cytochalasin B–treated
macrophages, binding was significantly affected. Binding
of PTX3-incubated PMNs was reduced by 50% compared with nonincubated PMNs, which suggests that
inhibition of phagocytosis by PTX3 is partly due to
reduced binding, whereas the residual inhibitory effect is
probably due to effects on internalization.
Rovere et al (5) have suggested that PTX3 did
not influence binding of apoptotic cells to immature
DCs, but only influenced their internalization. Physicochemical differences in the plasma membranes, the
different expression of membrane receptors between
macrophages and immature DCs, or the lack of exogenous serum cofactors in the study by Rovere et al may all
be relevant to explain these apparent discrepancies.
Opsonization of apoptotic cells by classic pentraxins has
been suggested to lead to direct or indirect recognition
by phagocytic cells. Indirect recognition occurs by activating complement, thereby enabling complement
receptor–dependent uptake via CR3 and CR4, whereas
direct recognition takes place via Fc␥R (19). CRP binds
to Fc␥RI and Fc␥RII, whereas SAP can also interact
with Fc␥RIII (25–27). However, other studies have
suggested that CRP does not bind to Fc␥R (28). Saeland
et al (29) indicated that the use of IgG1 anti-CRP
monoclonal antibodies to demonstrate binding of CRP
to Fc␥R raises technical problems, since these antibodies can bind through their Fc portion to Fc␥RII. The use
of biotinylated anti-CRP or anti-CRP F(ab⬘)2 for this
purpose did not result in binding of CRP to Fc␥RII (29).
It therefore remains a matter of debate whether CRP
really binds to Fc␥R.
The receptor capable of binding PTX3 has not
yet been identified, and the mechanisms by which PTX3
inhibits uptake of apoptotic cells are therefore unclear.
In vitro, PTX3 inhibits clearance of apoptotic cells
substantially at a concentration of 50 ␮g/ml, whereas
PTX3 in the serum of patients with active untreated
vasculitis reaches mean ⫾ SEM levels of only 6.17 ⫾
4.77 ng/ml (2), which calls into question the relevance of
the in vitro findings. However, since PTX3 is locally
produced in inflammatory tissue, serum levels of PTX3
do not reflect what is locally present at the site of
inflammation.
The biologic significance of the inhibitory capac-
PTX3 INHIBITS MACROPHAGE PHAGOCYTOSIS OF APOPTOTIC NEUTROPHILS
ity of PTX3 is still a subject of speculation. It has been
proposed that pentraxin-mediated clearance of apoptotic cells, similar to complement, represents a backup
mechanism for the clearance of late apoptotic cells in
situations in which apoptotic cell load is high and
clearance capacity is low (30). Rovere et al (5) suggested
that PTX3 acts as a local regulator inhibiting local
inflammatory uptake of late apoptotic cells by immature
DCs, thereby preventing antigen presentation by
antigen-presenting cells, which can be relevant for preventing induction of autoimmunity.
The inhibitory effect of PTX3 on phagocytosis of
apoptotic PMNs may be important in view of leukocytoclasia. Small-vessel vasculitides are histologically characterized by leukocytoclasia (i.e., the accumulation of
unscavenged apoptotic or necrotic PMNs in or around
the vessel wall). The defective clearance of cell debris
can in turn be involved in the maintenance of peripheral
inflammation. PTX3, a long extrahepatically produced
pentraxin, is released by a variety of cells in vitro, such as
fibroblasts, endothelial cells, and cells of the monocytic
lineage (9,31,32). Since PTX3 can be produced by
endothelial cells in active skin lesions of patients with
vasculitis (2), we hypothesize that inhibition of the
phagocytosis of apoptotic neutrophils by peripherally
produced PTX3 is responsible for the phenomenon of
leukocytoclasia in small-vessel vasculitis. It therefore
seems relevant to demonstrate the presence of PTX3 in
lesional tissue from patients with leukocytoclastic vasculitis. Such studies are under way in our laboratory.
REFERENCES
1. Goodman AR, Cardozo T, Abagyan R, Altmeyer A, Wisniewski
HG, Vilcek J. Long pentraxins: an emerging group of proteins with
diverse functions. Cytokine Growth Factor Rev 1996;7:191–202.
2. Fazzini F, Peri G, Doni A, Dell’Antonio G, Dal Cin E, Bozzolo E,
et al. PTX3 in small-vessel vasculitides: an independent indicator
of disease activity produced at sites of inflammation. Arthritis
Rheum 2001;44:2841–50.
3. Pepys MB, Baltz ML. Acute phase proteins with special reference
to C-reactive protein and related proteins (pentaxins) and serum
amyloid A protein. Adv Immunol 1983;34:141–212.
4. Bijl M, Horst G, Bijzet J, Bootsma H, Limburg PC, Kallenberg
CG. Serum amyloid P component binds to late apoptotic cells and
mediates their uptake by monocyte-derived macrophages. Arthritis Rheum 2003;48:248–54.
5. Rovere P, Peri G, Fazzini F, Bottazzi B, Doni A, Bondanza A, et
al. The long pentraxin PTX3 binds to apoptotic cells and regulates
their clearance by antigen-presenting dendritic cells. Blood 2000;
96:4300–6.
6. Koutkia P, Mylonakis E, Rounds S, Erickson A. Leucocytoclastic
vasculitis: an update for the clinician. Scand J Rheumatol 2001;
30:315–22.
7. Jessop SJ. Cutaneous leucocytoclastic vasculitis: a clinical and
aetiological study. Br J Rheumatol 1995;34:942–5.
2673
8. Grau GE, Roux-Lombard P, Gysler C, Lambert C, Lambert PH,
Dayer JM, et al. Serum cytokine changes in systemic vasculitis.
Immunology 1989;68:196–8.
9. Breviario F, d’Aniello EM, Golay J, Peri G, Bottazzi B, Bairoch A,
et al. Interleukin-1-inducible genes in endothelial cells: cloning of
a new gene related to C-reactive protein and serum amyloid P
component. J Biol Chem 1992;267:22190–7.
10. Bottazzi B, Vouret-Craviari V, Bastone A, De Gioia L, Matteucci
C, Peri G, et al. Multimer formation and ligand recognition by the
long pentraxin PTX3: similarities and differences with the short
pentraxins C-reactive protein and serum amyloid P component.
J Biol Chem 1997;272:32817–23.
11. Licht R, Jacobs CW, Tax WJ, Berden JH. An assay for the
quantitative measurement of in vitro phagocytosis of early apoptotic thymocytes by murine resident peritoneal macrophages. J Immunol Methods 1999;223:237–48.
12. Roos D, Goldstein IM, Kaplan HB, Weissmann G. Dissociation of
phagocytosis, metabolic stimulation and lysosomal enzyme release
in human leukocytes. Agents Actions 1976;6:256–9.
13. Duvall E, Wyllie AH, Morris RG. Macrophage recognition of cells
undergoing programmed cell death (apoptosis). Immunology
1985;56:351–8.
14. Russell L, Waring P, Beaver JP. Increased cell surface exposure of
fucose residues is a late event in apoptosis. Biochem Biophys Res
Commun 1998;250:449–53.
15. Gershov D, Kim S, Brot N, Elkon KB. C-reactive protein binds to
apoptotic cells, protects the cells from assembly of the terminal
complement components, and sustains an antiinflammatory innate
immune response: implications for systemic autoimmunity. J Exp
Med 2000;192:1353–64.
16. Holmskov U, Malhotra R, Sim RB, Jensenius JC. Collectins:
collagenous C-type lectins of the innate immune defense system.
Immunol Today 1994;15:67–74.
17. Korb LC, Ahearn JM. C1q binds directly and specifically to
surface blebs of apoptotic human keratinocytes: complement
deficiency and systemic lupus erythematosus revisited. J Immunol
1997;158:4525–8.
18. Nauta AJ, Trouw LA, Daha MR, Tijsma O, Nieuwland R,
Schwaeble WJ, et al. Direct binding of C1q to apoptotic cells and
cell blebs induces complement activation. Eur J Immunol 2002;32:
1726–36.
19. Mevorach D, Mascarenhas JO, Gershov D, Elkon KB. Complement-dependent clearance of apoptotic cells by human macrophages. J Exp Med 1998;188:2313–20.
20. Taylor PR, Carugati A, Fadok VA, Cook HT, Andrews M, Carroll
MC, et al. A hierarchical role for classical pathway complement
proteins in the clearance of apoptotic cells in vivo. J Exp Med
2000;192:359–66.
21. Gaipl US, Kuenkele S, Voll RE, Beyer TD, Kolowos W, Heyder P,
et al. Complement binding is an early feature of necrotic and a
rather late event during apoptotic cell death. Cell Death Differ
2001;8:327–34.
22. Familian A, Zwart B, Huisman HG, Rensink I, Roem D, Hordijk
PL, et al. Chromatin-independent binding of serum amyloid P
component to apoptotic cells. J Immunol 2001;167:647–54.
23. Mold C, Baca R, Du Clos TW. Serum amyloid P component and
C-reactive protein opsonize apoptotic cells for phagocytosis
through Fc␥ receptors. J Autoimmun 2002;19:147–54.
24. Garlanda C, Hirsch E, Bozza S, Salustri A, De Acetis M, Nota R,
et al. Non-redundant role of the long pentraxin PTX3 in antifungal innate immune response. Nature 2002;420:182–6.
25. Bharadwaj D, Mold C, Markham E, Du Clos TW. Serum amyloid
P component binds to Fc␥ receptors and opsonizes particles for
phagocytosis. J Immunol 2001;166:6735–41.
26. Bharadwaj D, Stein MP, Volzer M, Mold C, Du Clos TW. The
major receptor for C-reactive protein on leukocytes is fc␥ receptor
II. J Exp Med 1999;190:585–90.
2674
27. Stein MP, Edberg JC, Kimberly RP, Mangan EK, Bharadwaj D,
Mold C, et al. C-reactive protein binding to Fc␥RIIa on human
monocytes and neutrophils is allele-specific. J Clin Invest 2000;
105:369–76.
28. Hundt M, Zielinska-Skowronek M, Schmidt RE. Lack of specific
receptors for C-reactive protein on white blood cells. Eur J Immunol 2001;31:3475–83.
29. Saeland E, van Royen A, Hendriksen K, Vile-Weekhout H,
Rijkers GT, Sanders LA, et al. Human C-reactive protein does not
bind to Fc␥RIIa on phagocytic cells. J Clin Invest 2001;107:641–3.
VAN ROSSUM ET AL
30. Nauta AJ, Daha MR, Kooten C, Roos A. Recognition and
clearance of apoptotic cells: a role for complement and pentraxins.
Trends Immunol 2003;24:148–54.
31. Alles VV, Bottazzi B, Peri G, Golay J, Introna M, Mantovani A.
Inducible expression of PTX3, a new member of the pentraxin
family, in human mononuclear phagocytes. Blood 1994;84:
3483–93.
32. Lee GW, Lee TH, Vilcek J. TSG-14, a tumor necrosis factor- and
IL-1-inducible protein, is a novel member of the pentaxin family of
acute phase proteins. J Immunol 1993;150:1804–12.
Документ
Категория
Без категории
Просмотров
0
Размер файла
345 Кб
Теги
short, phagocytosis, contrast, serum, apoptotic, latex, tissue, prototype, neutrophils, macrophage, inhibits, amyloid, ptx3, pentraxin
1/--страниц
Пожаловаться на содержимое документа