| HOME | HELP | FEEDBACK | SUBSCRIPTIONS | ARCHIVE | SEARCH | TABLE OF CONTENTS |
|
|
|
|||||||
|
|||||||||
*
Division of Rheumatology, University of Connecticut Health Center, Farmington, CT 06030; and
Research Service, Veterans Administration Connecticut Healthcare System, Newington, CT 06111
 |
Abstract |
|---|
 Top Abstract IntroductionMaterials and MethodsResultsDiscussionReferences |
|---|
. Increased ICAM-1 expression was fibrin(ogen)
dose-dependent and was demonstrated by ELISA, flow cytometry, and
functional adhesion assays. Levels of ICAM-1 induced by fibrin(ogen)
were comparable to those that could be induced by cytokine stimulation.
Fibrin(ogen) stimulation of ICAM-1 could be suppressed by
pyrrolidinedithiocarbamate, an inhibitor of NF-
B activation.
Chemokine production was induced by fibrin(ogen) in cell culture
supernatants >100-fold as compared with controls. Thus, through its
activation of synovial fibroblasts, fibrin(ogen) deposition may promote
the recruitment (via chemokines) and retention (via adhesion molecules)
of lymphocytes within the arthritic joint. |
Introduction |
|---|
|
TopAbstractIntroductionMaterials and MethodsResultsDiscussionReferences |
|---|
Our laboratory has previously focused on cytokine pathways of adhesion molecule induction and adhesion molecule-related mechanisms thought to be of importance in connective tissue diseases such as rheumatoid arthritis (RA).3 In this disease, evidence for altered fibrinolysis has been demonstrated, for example, in plasma and synovial fluids in RA (13, 14). It has long been recognized that in most inflamed joints the coagulation system is activated, leading to the local generation of fibrin (15), and it has been hypothesized that the local fibrin deposition in arthritic joints could promote inflammation and destruction (16). Indeed, animal studies in which fibrin is implanted locally within joints induces a reaction that resembles human RA (17). More recent animal studies have shown that synovial fibrin deposition can sustain chronic arthritis. For example, Ag-induced arthritis in transgenic urokinase-deficient mice had more severe inflammation of longer duration, increased synovial thickness and bone erosions, and increased accumulation of fibrin as compared with controls (18). A double blind clinical trial of stanozolol (enhances both systemic and intra-articular fibrinolytic activity) in RA patients (19) resulted in clinical benefit, i.e., decrease in erythrocyte sedimentation rate, improvement in articular index, decreased duration of morning stiffness, decrease in pain, and decreased plasma fibrinogen concentrations. It was felt by these authors that the clinical improvement likely could have been due to the induced reduction of synovial fibrin. Additional studies have attempted to correlate associations between synovial fibrinolysis and levels of joint destruction in RA (20), a disease in which resident fibroblasts (FB) appear to play a crucial role. However, to our knowledge, direct effects of fibrin and/or fibrinogen (fibrin(ogen)) on FB have not been previously examined with regard to the generation and/or maintenance of inflammation within connective tissue. We used an in vitro assay to mimic fibrin(ogen) deposition on human synovial FB cultures derived from patients with RA. Our results suggest that the ability of fibrin(ogen) to induce adhesion molecule expression and potent chemokine production in human synovial FB may be a new and underappreciated pathway of inflammation occurring within the rheumatoid joint.
|
Materials and Methods |
|---|
|
TopAbstractIntroductionMaterials and MethodsResultsDiscussionReferences |
|---|
Human RA synovial tissue samples were obtained from patients undergoing joint replacement surgery at the University of Connecticut Health Center according to an Institutional Review Board-approved protocol. Tissues were minced and digested with 0.2% collagenase (Worthington type 1; Freehold, NJ) for 30–40 min at 37°C with agitation. Debris was allowed to settle and the supernatant containing single cells and small clusters was centrifuged to pellet the remaining cells. The cell pellets were washed two times with RPMI medium (Life Technologies, Grand Island, NY) containing 10% FCS (HyClone, Logan, UT), supplemented with 100 U/ml penicillin, 100 µg/ml streptomycin, and 2 mM L-glutamine. The synovial cells were seeded into 100-mm plastic tissue culture dishes (Costar, Cambridge, MA) and grown to confluence in the same medium. The outgrowth of FB-like synoviocytes are referred to as synovial FB cells. More than eight independently derived synovial cell lines were used for this study, and lines were used between passages 2 and 10.
ICAM-1 ELISA
The ELISA for determination of cell surface ICAM-1 expression
was performed as described by us previously (21) in
96-well plates. Confluent cultures of synovial cells were stimulated
with fibrinogen or other factors as indicated in the text. After
stimulation, cells were incubated with Ab to ICAM-1 (CD54) (RR1/1, a
gift of Dr. T. Springer, Center for Blood Research, Boston, MA, or
clone 15.2, purchased from Leinco, St. Louis, MO). Similar experimental
data were obtained using Ab obtained from either source. Secondary Ab
was HRP-conjugated goat anti-mouse IgG from Organon Teknika
(Durham, NC). The substrate used was ortho-phenylenediamine
in phosphate-citrate buffer, pH 5.0. Color development was terminated
after 
10–15 min of incubation by the addition of 2 M
H2SO4. Absorbance at 492 nm
was determined by using a Dynatech ELISA reader (MR 700; Dynatech
Laboratories, Chantilly, VA). Background absorbance was determined
using an isotype-matched mAb to murine CMV (a gift of Dr. J. Shanley,
University of Connecticut Health Center, Farmington, CT). ELISA data
are presented as the mean ± SD of triplicate determinations.
Flow cytometry
Cytometric analysis of synovial FB was performed as described previously (21, 22). Briefly, ICAM-1-specific fluorescence was assessed by staining the FB with mAb to ICAM-1 (RR1/1 or clone 15.2) followed by FITC anti-Ig (Organon Teknika). Nonspecific fluorescence was assessed by staining with irrelevant isotype-matched mAb followed by FITC anti-Ig. Samples were analyzed with a Coulter Epics Profile II flow cytometer (Coulter Electronics, Hialeah, FL).
Positive regions were set to exclude 97% of nonspecifically stained cells. Cells were analyzed by selective gating on the parameters of forward and 90° light scatter. Ag density was indirectly determined by assessing the mean fluorescence channel (MFC) of the samples. As possible, a minimum of 10,000 cells per sample was analyzed.
Preparation of human lymphocytes
PBMC were obtained from normal, healthy donors of both sexes and prepared by Ficoll-diatrizoate (Sigma, St. Louis, MO) centrifugation and passage through a nylon wool column (23). Nonadherent cells were depleted of residual monocytes by a brief treatment with 5 mM L-leucine methyl ester (24). This T cell-enriched population (>98% OKT3+ cells, <0.5% monocytes) was used as the source of cells for adherence studies.
Cell-cell adhesion assay
Details of the cell adherence assay have been described previously (21, 22). Briefly, monolayers of confluent synovial FB in 96-well plates were incubated at 37°C with various control or experimental factors as described in the text. At the end of incubation, factors were removed and cell layers were washed with medium or warm PBS before the addition of 100 µl of a suspension containing 3 x 106 T cells/ml. After an incubation period of 1 h at 37°C, nonadherent T cells were removed by repeated gentle washing of the monolayers with warm PBS and aspiration using a blunted 21-gauge needle. Where indicated in the text, mAb were added to FB cultures for 60 min at 37°C, followed by washing of the cell layer before the addition of T cells.
Quantitation of adherent T cells was obtained by microscopic examination after the monolayers were air dried and stained with 1% methylene blue. Two random fields in each well were counted using an ocular grid; fields were selected away from the edges of the well where washing may have been incomplete in removing nonadherent lymphocytes. Adhesion is expressed as the number of adherent lymphocytes per grid. Each experiment was performed with triplicate cultures, and results are expressed as mean ± SD.
Reagents
Purified human fibrinogen (95% clottable) was purchased from
Sigma Diagnostics (St. Louis, MO). Fibrinogen purity was assessed by
SDS-PAGE followed by silver staining and was observed to be undegraded
and free of contaminating proteins. For use in experiments, fibrinogen
concentrations were prepared in chemically defined serum-free medium
(AIM V; Life Technologies), and the cell cultures were maintained in
the same serum-free medium. Purified human thrombin (T6634), plasmin
(P7911), and pyrrolidinedithiocarbamate (PDTC) were obtained from
Sigma. Polymerized native type 1 collagen gels (Vitrogen 100; Collagen
Aesthetics, Palo Alto, CA ) were prepared as described by Delvos et al.
(25). Low melting point agarose was obtained from Life
Technologies. Human rIL-1ß was purchased from Genome Therapeutics
(Bedford, MA). Human TNF- was obtained from R&D Systems
(Minneapolis, MN). Human recombinant IFN-
(activity 1.6 x
104 U/µg) was obtained from Biogen (Cambridge,
MA). Kits for the determination of the chemokines IL-8 (sensitivity
<10 pg/ml), growth-related oncogene- (GRO-; sensitivity <5
pg/ml), and IL-1ß (sensitivity <0.3 pg/ml) in culture supernatants
were purchased from R&D Systems.
|
Results |
|---|
|
TopAbstractIntroductionMaterials and MethodsResultsDiscussionReferences |
|---|
The ability of fibrin(ogen) to induce ICAM-1 surface expression in
synovial FB was initially evaluated by ELISA. FB monolayers were grown
to confluence in 96-well plates. Freshly prepared, human fibrinogen
(FGN) was added to the cultures, and the cells were incubated overnight
at 37°C before beginning the ELISA. Table I
shows that incubation of three
different human synovial FB lines with fibrinogen led to an increase in
the surface expression of ICAM-1. The increase in ICAM-1 caused by FGN
was usually comparable to that which could be induced by incubation
with the cytokine IFN-, a known inducer of ICAM-1 for these
cells.
|
shows a dose-dependent increase in synovial FB expression of ICAM-1 as
the concentration of FGN was increased. The highest concentration of
FGN used (1.2 mg/ml) could induce a >5-fold increase in the baseline
expression of ICAM-1. As little as 0.01 mg/ml produced a 50% increase
in baseline expression. Concentrations of FGN <0.01 mg/ml did not
significantly alter the baseline expression of ICAM-1.
|
, with each line tested, we
observed that incubation with FGN led to both an increase in the number
of cells expressing ICAM-1 and/or an increase in the MFC of the samples
(MFC is in log scale), indicating an increase of ICAM-1 density on a
per cell basis as well.
|
We previously reported that polymerized fibrin, but not
unpolymerized FGN, could induce adhesion molecule expression on human
vascular endothelial cells (26). Therefore, we wanted to
assess the effect of the addition of thrombin to our FGN synovial cell
coculture. As thrombin itself has been implicated in the up-regulation
of adhesion molecules in other in vitro cell assays (27, 28), we first performed a thrombin titration experiment to
examine such direct effects in our assay. In our previous studies on
endothelial cells, we used 0.24 U/ml of purified human thrombin to
polymerize the equivalent concentrations of FGN used here in our
synovial cell study. Fig. 2 shows clearly
that this amount of thrombin in our synovial cell cultures had no
direct effect on ICAM-1 expression. Indeed, no effect on ICAM-1
expression was noted when up to a 40-fold increase in this amount of
thrombin was used. We then compared the ability of FGN and the
combination of FGN plus thrombin (to promote FGN polymerization to
fibrin clot) to induce ICAM-1 on the synovial cells. We incubated
several lines of synovial cells with FGN (0.6 and 0.3 mg/ml) or with
the same concentrations of FGN with added thrombin (0.24 U/ml) to
induce polymerization of the FGN. Visible polymerization of the FGN was
usually evident in the culture wells within the first 30 min following
thrombin addition. After an overnight incubation at 37°C, all
reagents and the loosely adherent fibrin clots were removed by
aspiration and the cells were washed twice with medium. Visual
inspection of the cell monolayers was performed to assess that the
monolayers remained intact following clot and reagent removal. ICAM-1
expression of the synovial cells was determined by ELISA. Table III shows that the levels of ICAM-1
induced by the combination of FGN and thrombin was not significantly
different from the levels of ICAM-1 observed with FGN alone. We
observed a tendency for the cultures receiving both FGN and thrombin to
display somewhat lower ICAM-1 values by ELISA. These culture wells
contained the semisolid clots that formed contacts with the cell
monolayer, albeit loosely, and some cell loss could occasionally be
noted following clot removal. This could have contributed to the
slightly lower values obtained. Therefore, we used flow cytometry to
eliminate this source of variability to examine further whether the
addition of thrombin could influence FGN-induced ICAM-1 expression. As
shown in Table IV, using cytometry, we
observed no significant decrease or increase in the expression of
ICAM-1 induced by FGN as compared with the FGN and thrombin
combination. Cytometry also confirmed our earlier ELISA results that
baseline expression of ICAM-1 remained stable in the presence of
thrombin alone.
|
|
|
shows that synovial cell incubation
with agarose or collagen gels did not induce a strong up-regulation of
ICAM-1, in contrast to the effect observed in synovial cultures
incubated with equal concentrations of FGN. In addition, in an effort
to reduce or eliminate possible effects of endogenous protease
production by the synovial cells, we preincubated cultures with the
following protease inhibitors (40–1 µg/ml) for 30 min to 1 h
before the addition of FGN: benzamidine, soybean trypsin inhibitor,
PMSF, leupeptin, iodoacetamide, and aprotinin. ICAM-1 expression
induced by FGN, as determined by ELISA, was unchanged by the addition
of these inhibitors as compared with identical cultures prepared in the
absence of the inhibitors (data not shown).
|
We examined whether the increase in ICAM-1 expression induced in
the synovial FB by FGN would correlate with a functional increase in
the adhesion of human T lymphocytes. Synovial FB were plated in 96-well
culture plates and allowed to reach confluence. After an overnight
incubation with FGN, the cultures were washed and a suspension of T
cells was added (100 µl containing 3 x
105 T cells) to each well, and the cultures were
incubated for an additional hour at 37°C to allow the T cells to
settle onto the monolayer. Cells were again washed with warm medium or
PBS to remove nonadherent T cells. After drying and staining, numbers
of adherent T cells were counted under a microscope using an ocular
grid. The cytokine IFN- was used as a positive control for increased
T cell adhesion to the synovial FB.
FGN-stimulated FB increased their adhesiveness for T lymphocytes over
that of the unstimulated control cells (baseline adherent T cells/grid
was 81 ± 5 compared with 215 ± 21 for FGN treatment) (Fig. 4). We considered the possibility that
the increase in adhesion we observed may be due, in part, to
nonspecific attachment of the T cells to the FGN-treated FB, and
possibly to nonspecific attachment to residual FGN itself, for the
following reasons: 1) FGN, by nature, is a "sticky" substance,
which may not be completely removed from the synovial monolayers by
washing (indeed, we obtained immunohistochemical evidence of small
amounts of residual FGN remaining in the culture wells after washing
using FGN-specific Abs) and 2) it has been previously shown by D’Souza
et al. that FGN may itself directly bind to ICAM-1 on Raji cell
surfaces (30). Such directly bound FGN (if it occurs on
synovial cells) may provide a nonspecific substrate for the T cells in
our assay. We determined that after removal of FGN by aspiration and
washing, any residual FGN could be completely removed (as assayed by
immunohistochemistry) by a 1-h treatment of the washed cultures with 1
U/ml of purified plasmin. As shown in Fig. 4, cells stimulated with FGN
and followed by a 1-h plasmin treatment to remove residual FGN before
the addition of T cells displayed a similar increase in adhesion as was
observed in the absence of plasmin. Control experiments demonstrated
that the plasmin treatment did not affect either the baseline levels of
adhesion or the level of increased adhesion due to stimulation of the
cells with IFN-. To more directly determine the role of specificity
in our adhesion assay, replicate experimental cultures were pretreated
with adhesion-blocking Ab to ICAM-1 (Leinco) for 1 h before the
addition of T cells. The inclusion of the Ab confirmed that the
increase in adhesion we observed in FGN-treated cells was, in part,
truly ICAM-1 dependent. As inclusion of blocking Ab to ICAM-1 did not
reduce the FGN-stimulated adhesion fully to baseline levels, FGN, as is
already known for IFN-, may also induce the expression of additional
adhesion molecules on synovial FB.
|
PDTC is an antioxidant that prevents both NF-B activation and
translocation to the nucleus (31, 32), and has been used
to demonstrate a role for NF-B signaling in ICAM-1 expression in
cytokine-treated cells such as FB (33). We pretreated
synovial FB with 25 µM PDTC for 1 h before stimulating the cells
with either FGN or IL-1 to induce ICAM-1 synthesis. As expected,
pretreatment of FB with PDTC inhibited the increase in ICAM-1
expression induced by the cytokine IL-1 (Table V). Similarly, PDTC was able to inhibit
the increase in ICAM-1 expression induced by FGN. These results imply a
mechanistic role for NF-B in the induction of ICAM-1 in synovial FB
promoted by FGN.
|
Fibrinogen has been shown to induce the production of the
chemokine IL-8 in addition to ICAM-1 in human endothelial cells
(25, 34). We investigated the possibility of IL-8
induction by FGN stimulation of the synovial FB by examining
culture supernatants for the presence of IL-8 by using a commercial
ELISA kit. Supernatants were collected from 96-well cultures of three
different synovial cell lines that had been incubated overnight in
medium alone (control) or in medium containing 0.3 mg/ml FGN. Table VI shows that FGN was able to induce
significant amounts of IL-8 secretion into the supernatants of all
three lines. In two of the three lines tested, baseline IL-8 production
was undetectable, yet increased to 5500 and 6500 pg/ml with overnight
FGN exposure. The third line tested also reached similar levels of
FGN-induced IL-8 secretion, up from a baseline value of 750 pg/ml. As
also shown in Table VI, FGN stimulated the production of GRO- into
the culture supernatants well over 100-fold over the unstimulated
levels. IL-1 was not detected in the culture supernatants of either
control or FGN-stimulated cultures. Stimulation of the synovial cells
by TNF- and IFN- is included for comparison.
|
|
Discussion |
|---|
|
TopAbstractIntroductionMaterials and MethodsResultsDiscussionReferences |
|---|
340 kDa, and occurs in
normal plasma at concentrations of 3 mg/ml. Because fibrinogen is
also an acute phase reactant, levels in the plasma can rise as high as
7 mg/ml in some diseases (35). In both acute and chronic
inflammatory reactions, fibrin deposition and leukocyte accumulation
are classic histopathologic hallmarks. The interrelationship between
fibrin deposition and leukocyte accumulation is just beginning to be
examined in such instances. In the chronic inflammatory setting of RA, synovial hyperplasia, inflammatory cell recruitment, and intra-articular fibrin deposition are important features of the disease (36). Although normal synovial fluid does not contain fibrinogen (37), many studies attest to the presence of an abundance of fibrinogen as well as fibrinogen fragments, breakdown products, and coagulation-associated factors in both the synovial fluids and tissues of patients with RA (indicative of the complex coagulopathy that exists in RA; Refs. 28, 38, 39, 40, 41). Quantitative studies of fibrinogen antigenic proteins in synovial fluid have correlated higher levels of these substances with higher inflammatory indices (38, 39, 42). A suspected role for fibrin in the pathogenesis of the disease is supported by many studies beginning with the early demonstration that chronic arthritis could be induced in rabbits by intra-articular fibrin injection (43). Fibrin(ogen) and its breakdown products of liberated chains and fragments are beginning to be identified as specific mediators of cellular processes (44, 45, 46, 47) and are now suspected to play active roles in the induction and maintenance of inflammatory conditions (16, 17, 18, 19, 20, 25, 34).
We and others have previously reported that fibrin deposition onto endothelial cell monolayers in vitro resulted in the increased expression of cell adhesion molecules as well as enhanced IL-8 production (25, 34), proposing an active role for intravascular fibrin deposition in leukocyte recruitment and retention. As prominent adhesion molecule expression, leukocyte accumulation, and fibrin(ogen) deposition are all important features of inflammatory RA, we similarly investigated whether fibrin(ogen) deposition in vitro on synovial FB from patients with RA would also lead to increased adhesion molecule expression and/or chemokine production.
We were able to demonstrate by using ELISA, flow cytometry, and functional adhesion assays that fibrin(ogen) coculture with human synovial FB resulted in the up-regulation of ICAM-1, a key component of inflammation in the rheumatic joint. By flow cytometry, we determined that some synovial cell lines increased their expression of ICAM-1 in two ways, an increase in the percentage of cells displaying surface ICAM-1, as well as an increase in the surface density of ICAM-1. Cell lines that initially contained a high percentage of ICAM-1-expressing cells (>96%) responded primarily by an increase in their surface density of ICAM-1. By the use of cell-cell adhesion assays, we determined that the increase in ICAM-1 correlated with an increase in the adhesive capacity of the synovial FB for T cells, an increase that could largely, but not completely, be inhibited by Ab to ICAM-1. Therefore, we hypothesize that fibrin(ogen) may induce additional adhesion molecules on the synovial FB.
We showed earlier that polymerization of fibrinogen to fibrin was
necessary for the induction of ICAM-1 on endothelial cells
(25). Sporn et al. (44) showed that fibrin
prepared by thrombin cleavage resulted in maximal proliferation of
human endothelial cells and FB when cultured on fibrin(ogen) surfaces.
Inclusion of thrombin to polymerize fibrinogen did not appreciably
alter our findings of increased ICAM-1 on synovial cells. Thrombin
itself can alter many cell functions such as adhesion molecule
expression and chemotaxis, and can produce mitogenic effects (26, 27, 48); however, at the concentrations tested in our assays,
thrombin was not an effective stimulator of ICAM-1. However, we needed
to consider that synovial cells, especially those derived from patients
with active disease, can secrete a variety of proteases, including
thrombin-like proteases, that could have fibrinolytic effects
(28, 41), resulting in a layer of polymerized fibrin
occurring close to the cell surface, thereby necessitating our use of
the term fibrin(ogen). This polymerized layer could have altered cell
functions by such nonspecific means as physical gel contraction,
mechanical pressure, or impaired oxygen or nutrient diffusion.
Experiments in which we polymerized native collagen and agarose gels
while these substances were in contact with the synovial cells were
without effect on ICAM-1 expression and argue against such a
nonspecific mechanism. However, our experiments using various protease
inhibitors notwithstanding, we have not eliminated the possibility that
fibrinogen polymerization at the cell surface due to endogenous
proteases may be a specific mechanism by which the effects we observed
on synovial cells occurred. Harley et al. have recently reported that
cleavage of fibrinopeptide B from the B/ß chain of fibrinogen by
endogenous urokinase plasminogen activator on endothelial cells permits
the exposure of a previously sequestered amino acid sequence that alone
can up-regulate the expression of ICAM-1 on these cells
(42). We have also observed that certain internal
sequences of the A/ chain of fibrinogen, which may become exposed
during fibrinogenesis, can increase the ICAM-1 expression on synovial
FB (X. Liu and T. H. Piela-Smith, manuscript in preparation).
However, it must be remembered that in vivo, intact fibrinogen as well
as fibrin monomers, polymerized fibrin, fibrin fragments of various
sizes, and "fibrin-like material," are all found associated with
synovial fluids and tissues as well as numerous activators and
inhibitors of fibrinolysis (28, 38, 39, 40, 41). Precise
substrate(s) responsible for synovial cell activation are likely
complex and remain to be identified.
Induction of synovial ICAM-1 by fibrin(ogen) was inhibited by PDTC, an
antioxidant that prevents NF-B activation and its translocation to
the nucleus (31, 32). NF-B is well known to affect a
broad array of immediate-early gene products such as TNF, ILs,
chemokines, and CSFs, genes that are tightly regulated during
inflammation and wound healing. ICAM-1 expression by human tracheal
smooth muscle cells is dependent upon NF-B, and PDTC has been shown
to inhibit the up-regulation of ICAM-1 on human FB stimulated by
IL-1ß, IFN-, and PMA (33, 49). Our experiments
suggest the addition of fibrin(ogen) to this list of PDTC-sensitive
inducers of FB ICAM-1.
The secretion of potent chemotactic factors by synovial cells is
thought be an important mechanism by which lymphocyte recruitment
occurs in the inflamed joint. Elevated levels of the chemokines IL-8,
monocyte chemoattractant protein-1, and RANTES are detected in the
synovial tissue of RA patients but not in normal synovial tissues, and
can be detected in the supernatants of in vitro cultures of synovial FB
derived from RA patients (50, 51). We found that
stimulation of the synovial FB with fibrin(ogen) resulted in the
enhanced production of the chemokines IL-8 and GRO-.
Because the genesis of immune reactions is largely at fixed tissue sites that are rich in FB, an understanding of the processes involved in lymphocyte recruitment, localization, and residence at these sites is critical not only in normal inflammation, but in chronic inflammatory conditions in which FB/lymphocyte interactions are thought to be pathogenic, such as in RA. Our results demonstrating that fibrin(ogen) deposition on synovial FB can enhance the expression of adhesion molecules and lymphocyte chemotactic factors add further information supporting earlier findings that indirectly suggested a role for fibrin(ogen) in the promotion of inflammation. Synovial FB are in direct contact with extravascular spaces or compartments where fibrin can be formed, and could be expected to undergo such activation. We hypothesize that, in vivo, fibrin(ogen)-induced activation of synovial FB (through induction of adhesion molecules and chemokine production), could lead to the recruitment, activation, attachment, and retention of lymphocytes, all of which occur to a tremendous degree in the chronically inflamed joint.
|
Acknowledgments |
|---|
|
Footnotes |
|---|
2 Address correspondence and reprint requests to Dr. Theresa H. Piela-Smith, Veterans Administration Connecticut Health Care System, Research Building 5, 555 Willard Avenue, Newington, CT 06111.
3 Abbreviations used in this paper: RA, rheumatoid arthritis; PDTC, pyrrolidinedithiocarbamate; GRO-, growth-related oncogene-; FB, fibroblast(s); fibrin(ogen), fibrin and/or fibrinogen; MFC, mean fluorescence channel; FGN, human fibrinogen.
Received for publication April 6, 2000. Accepted for publication August 10, 2000.
|
References |
|---|
|
TopAbstractIntroductionMaterials and MethodsResultsDiscussionReferences |
|---|
irradiation. J. Immunol. 148:41.[Abstract]
B in intact cells. J. Exp. Med. 175:1181.B dependent signalling pathway that is only partially sensitive to dexamethasone. J. Immunol. 163:2128.This article has been cited by other articles:
|
|
 |
|
  A Masamune, K Kikuta, T Watanabe, K Satoh, M Hirota, S Hamada, and T Shimosegawa Fibrinogen induces cytokine and collagen production in pancreatic stellate cells Gut, April 1, 2009; 58(4): 550 - 559. [Abstract] [Full Text] [PDF]
|
|
|
|
 |
|
 M. Nakayama-Hamada, A. Suzuki, H. Furukawa, R. Yamada, and K. Yamamoto Citrullinated Fibrinogen Inhibits Thrombin-catalysed Fibrin Polymerization J. Biochem., September 1, 2008; 144(3): 393 - 398. [Abstract] [Full Text] [PDF]
|
|
|
|
 |
|
 J. Mu, D. Qu, A. Bartczak, M. J. Phillips, J. Manuel, W. He, C. Koscik, M. Mendicino, L. Zhang, D. A. Clark, et al. Fgl2 deficiency causes neonatal death and cardiac dysfunction during embryonic and postnatal development in mice Physiol Genomics, September 11, 2007; 31(1): 53 - 62. [Abstract] [Full Text] [PDF]
|
|
|
|
 |
|
 E. A. Lefevre, W. R. Hein, Z. Stamataki, L. S. Brackenbury, E. A. Supple, L. G. Hunt, P. Monaghan, G. Borhis, Y. Richard, and B. Charleston Fibrinogen is localized on dark zone follicular dendritic cells in vivo and enhances the proliferation and survival of a centroblastic cell line in vitro J. Leukoc. Biol., September 1, 2007; 82(3): 666 - 677. [Abstract] [Full Text] [PDF]
|
|
|
|
 |
|
 O Sanchez-Pernaute, J Esparza-Gordillo, R Largo, E Calvo, M A Alvarez-Soria, M E Marcos, G Herrero-Beaumont, and S R de Cordoba Expression of the peptide C4b-binding protein {beta} in the arthritic joint Ann Rheum Dis, October 1, 2006; 65(10): 1279 - 1285. [Abstract] [Full Text] [PDF]
|
|
|
|
 |
|
 H. Fujimoto, E. C. Gabazza, O. Taguchi, Y. Nishii, H. Nakahara, N. E. Bruno, C. N. D'Alessandro-Gabazza, M. Kasper, Y. Yano, M. Nagashima, et al. Thrombin-Activatable Fibrinolysis Inhibitor Deficiency Attenuates Bleomycin-Induced Lung Fibrosis Am. J. Pathol., April 1, 2006; 168(4): 1086 - 1096. [Abstract] [Full Text] [PDF]
|
|
|
|
 |
|
 M. T. Follettie, M. Pinard, J. C. Keith Jr., L. Wang, D. Chelsky, C. Hayward, P. Kearney, P. Thibault, E. Paramithiotis, A. J. Dorner, et al. Organ Messenger Ribonucleic Acid and Plasma Proteome Changes in the Adjuvant-Induced Arthritis Model: Responses to Disease Induction and Therapy with the Estrogen Receptor-{beta} Selective Agonist ERB-041 Endocrinology, February 1, 2006; 147(2): 714 - 723. [Abstract] [Full Text] [PDF]
|
|
|
|
 |
|
 M. Mendicino, M. Liu, A. Ghanekar, W. He, C. Koscik, I. Shalev, M. Javadi, J. Turnbull, W. Chen, L. Fung, et al. Targeted Deletion of Fgl-2/Fibroleukin in the Donor Modulates Immunologic Response and Acute Vascular Rejection in Cardiac Xenografts Circulation, July 12, 2005; 112(2): 248 - 256. [Abstract] [Full Text] [PDF]
|
|
|
|
 |
|
 K.-I. Inoue, H. Takano, A. Shimada, R. Yanagisawa, M. Sakurai, S. Yoshino, H. Sato, and T. Yoshikawa Urinary Trypsin Inhibitor Protects against Systemic Inflammation Induced by Lipopolysaccharide Mol. Pharmacol., March 1, 2005; 67(3): 673 - 680. [Abstract] [Full Text] [PDF]
|
|
|
|
|
|
O Sanchez-Pernaute, R Largo, E Calvo, M A Alvarez-Soria, J Egido, and G Herrero-Beaumont A fibrin based model for rheumatoid synovitis Ann Rheum Dis, December 1, 2003; 62(12): 1135 - 1138. [Abstract] [Full Text] [PDF]
|
|
|
|
 |
|
 O. Sanchez-Pernaute, M. J. Lopez-Armada, E. Calvo, I. Diez-Ortego, R. Largo, J. Egido, and G. Herrero-Beaumont Fibrin generated in the synovial fluid activates intimal cells from their apical surface: a sequential morphological study in antigen-induced arthritis Rheumatology, January 1, 2003; 42(1): 19 - 25. [Abstract] [Full Text] [PDF]
|
|
|
|
|
|
H. Park, S. G. Park, J.-W. Lee, T. Kim, G. Kim, Y.-G. Ko, and S. Kim Monocyte cell adhesion induced by a human aminoacyl-tRNA synthetase-associated factor, p43: identification of the related adhesion molecules and signal pathways J. Leukoc. Biol., February 1, 2002; 71(2): 223 - 230. [Abstract] [Full Text] [PDF]
|
|
|
|
 |
|
 F. M. Szaba and S. T. Smiley Roles for thrombin and fibrin(ogen) in cytokine/chemokine production and macrophage adhesion in vivo Blood, February 1, 2002; 99(3): 1053 - 1059. [Abstract] [Full Text] [PDF]
|
|
|
|
 |
|
 S. T. Smiley, J. A. King, and W. W. Hancock Fibrinogen Stimulates Macrophage Chemokine Secretion Through Toll-Like Receptor 4 J. Immunol., September 1, 2001; 167(5): 2887 - 2894. [Abstract] [Full Text] [PDF]
|
|
| |||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||
| HOME | HELP | FEEDBACK | SUBSCRIPTIONS | ARCHIVE | SEARCH | TABLE OF CONTENTS |
