(Journal of Leukocyte Biology. 2000;68:144-150.)
© 2000
by Society for Leukocyte Biology
The colony-stimulating factors and collagen-induced arthritis: exacerbation of disease by M-CSF and G-CSF and requirement for endogenous M-CSF
Ian K. Campbell,
Melissa J. Rich,
Robert J. Bischof and
John A. Hamilton
Inflammation Research Centre, The University of Melbourne, Department of Medicine, Royal Melbourne Hospital, Parkville, Victoria 3050, Australia
 |
ABSTRACT
|
|---|
There is increasing evidence that the colony-stimulating factors (CSFs)
may play a part in chronic inflammatory autoimmune diseases, such as
rheumatoid arthritis (RA). We examined the involvement of macrophage
CSF (M-CSF or CSF-1) and granulocyte CSF (G-CSF) in collagen-induced
arthritis (CIA), a murine model of RA. Daily injections of M-CSF or
G-CSF, 2024 days postprimary immunization with type II collagen,
exacerbated disease symptoms in suboptimally immunized DBA/1 mice.
Support for the involvement of endogenous M-CSF in CIA was obtained by
studies in which neutralizing monoclonal antibody reduced the severity
of established CIA and also by studies showing the resistance of
M-CSF-deficient op/op mice to CIA induction. These studies
show that M-CSF and G-CSF can be proinflammatory in CIA and provide
evidence that macrophage- and granulocyte-lineage cells can exacerbate
CIA. Our results also show that M-CSF-dependent cells are essential for
CIA development, suggesting M-CSF may be a suitable target for
therapeutic intervention in RA.
Key Words: rheumatoid arthritis hematopoiesis cytokines inflammatory mediators in vivo animal models
 |
INTRODUCTION
|
|---|
The colony-stimulating factors (CSFs) are a family of four
cytokine growth factors originally identified by their ability to
support the proliferation and differentiation of haemopoietic
progenitor stem cells into mature monocytes/macrophages and
granulocytes [for review, see ref. 1
]. The CSF family comprises the
lineage-specific members, macrophage CSF (M-CSF or CSF-1) and
granulocyte CSF (G-CSF), and the nonlineage-specific members,
granulocyte-macrophage CSF (GM-CSF) and multi-CSF [also called
interleukin (IL)-3]. Although known for their actions in haemopoiesis,
the CSFs in vitro also exhibit certain activities that could
predispose them toward a proinflammatory role in vivo
[1
, 2
].
There is increasing evidence that CSFs may play a major part in chronic
inflammatory autoimmune diseases, such as rheumatoid arthritis (RA).
Three of the four known CSFs (M-CSF, G-CSF, and GM-CSF) are produced by
human-joint tissue cells (chondrocytes, synovial fibroblasts) in
vitro in response to the inflammatory cytokines, IL-1 and tumor
necrosis factor
(TNF-
) [3
4
5
6
]. Certain CSFs have
also been identified in RA joint exudates [7
,
8
] and in RA synovial tissues by in situ
hybridization [9
]. We recently obtained more direct
evidence of a role for CSFs in inflammatory arthritis by demonstrating
that GM-CSF can exacerbate disease symptoms when injected into mice
sensitized to develop collagen-induced arthritis (CIA)
[10
] and that GM-CSF-deficient mice are resistant to the
induction of CIA [11
]. Because GM-CSF can affect cells
of the monocytic, granulocytic, and dendritic cell lineages, its key
target cell in autoimmune arthritis remains obscure.
The ability of M-CSF and G-CSF to affect specific haemopoietic cell
lineages presents a unique opportunity to dissect and assess the
relative contributions of two major cellular pathways of GM-CSF action
in CIA and to gain a better understanding of their separate
contributions to disease. Although a previous study [12
]
described exacerbation of disease in the Streptococcus
agalactiae rat model of arthritis by intravenous (i.v.) injection
of recombinant human (rh) M-CSF, little is known of the actions of this
cytokine in an autoimmune model of arthritis, such as CIA, or whether
endogenous M-CSF is required for disease development. Also, to our
knowledge, there is only one study describing the effect of G-CSF on an
animal arthritis model [13
]. This is surprising given
that it has been administered to patients with Feltys syndrome (a
variant of RA) for treatment of neutropenia [14
15
16
17
18
] and
is being used for the mobilization of haemopoietic stem cells in
patients with severe RA prior to myeloablation [19
].
The aim of this study was to obtain a better understanding of the role
of M-CSF and G-CSF in autoimmune arthritis. Several approaches were
used to investigate the involvement of M-CSF, and to a lesser extent
G-CSF, in CIA. We show that exogenous M-CSF and G-CSF can exacerbate
arthritis symptoms when injected into mice suboptimally primed to
develop CIA. We also show that endogenous M-CSF is required for CIA
development, because disease severity is reduced in arthritic mice
treated with neutralizing monoclonal antibodies (mAbs) to M-CSF, and
CIA could not be established in M-CSF-deficient (op/op)
mice. These findings extend the proinflammatory potential of the CSF
family. Our results also suggest possible new targets for therapeutic
intervention in RA and suggest caution should be exercised when using
G-CSF for therapeutic purposes in RA.
 |
MATERIALS AND METHODS
|
|---|
Reagents
Chick type-II collagen (CII) and incomplete Freunds adjuvant
were purchased from Sigma Chemical Co. (St. Louis, MO); heat-killed
Mycobacterium tuberculosis (H37Ra) and lipopolysaccharide
(LPS) (Eschericia coli strain 0111:B4) were purchased from
Difco Laboratories (Detroit, MI). rhM-CSF (specific activity
8x107 units/mg by M-NFS-60 cell proliferation assay) was a
gift from Chiron Corp. (Emeryville, CA); rhG-CSF and rhIL-1ß
(specific activity 5x108 units/mg; units as defined in
ref. 3
) were obtained from Amgen Inc. (Thousand Oaks, CA). Rat mAb to
M-CSF, 5A1, and its isotype control mAb, DX48 [rat immunoglobulin G1
(IgG1) raised to digoxin], were gifts from F. Kull (Glaxo-Wellcome,
Research Triangle Park, NC). The neutralizing capacity of 5A1 was
7 x 105 units of M-CSF per mg 5A1. M-CSF and G-CSF
were carrier-free and were diluted in phosphate-buffered saline (PBS)
or normal saline for experimentation.
Mice
Male DBA/1 mice (711 weeks old) were purchased from the Animal
Resources Centre (Canning Vale, Western Australia) and allowed to
acclimate for 1 week before experimentation. DBA/1 mice were fed
standard rodent chow and water ad libitum and were housed in
sawdust-lined cages in groups of five. Osteopetrotic (op/op)
mutant mice and their littermate wild-type controls, each on the
C57BL/6 and C3HeB/FeJ background, were obtained from the Ludwig
Institute for Cancer Research (Parkville, Victoria, Australia) and
maintained in micro-isolators within the Ludwig Institutes animal
house facility. Following weaning, the op/op mice, which
lacked incisors, were maintained on a diet containing equal amounts of
powdered chow and Ensure nutritional powder (VHA Trading Co., Mulgrave,
Victoria, Australia), mixed in sterile water.
Collagen-induced arthritis
An emulsion was formed by dissolving 2 mg/ml chick CII overnight
at 4°C in 10 mM acetic acid and combining it with an equal volume of
complete Freunds adjuvant (CFA), prepared by adding heat-killed
M. tuberculosis to incomplete Freunds adjuvant at 5 mg/ml.
All mice were injected intradermally (i.d.) at several sites into the
base of the tail with a total of 100 µl emulsion containing 100 µg
CII and 250 µg M. tuberculosis. Depending on the
experiment, mice were then treated in one of three ways.
(1) Exacerbation studies (suboptimum CIA)
Mice in this group received no further injections of CII. This
procedure followed that previously described [10
], where
omission of a booster injection resulted in suboptimal induction of
CIA. After different periods of time, mice were given 45 daily
injections of M-CSF or G-CSF, or the same volume of vehicle at the
doses, routes, and times indicated in the text.
(2) Neutralizing mAb studies (optimum CIA)
In experiments to examine the effect of neutralizing mAbs, mice
were immunized for maximum CIA response by administration of a repeat
of the primary CII injection as a boost at day 21, as previously
described [11
]. Mice were then assessed daily for
clinical signs of CIA and, from 27 days postprimary immunization
onward, newly arthritic mice were randomly assigned to one of two mAb
treatment groups5A1 or DX48. The arthritic mice were then given 10
consecutive daily intraperitoneal (i.p.) injections of mAb (300 µg),
and the arthritis was assessed clinically throughout.
(3) IL-1 enhancement of CIA (optimum CIA)
In some experiments (indicated in text), the rapid onset of CIA
was induced, as described [20
], by four consecutive
daily subcutaneous (s.c.) injections into the rear footpad with IL-1ß
(20 ng, 104 units). The injections were initiated at 21
days postprimary CII immunization, and no CII boost was given.
Clinical and histological assessment of arthritis
Mouse limbs were assessed for redness and swelling, and a
clinical score was allocated 23 times per week for up to 60 days. The
scoring system was as previously described [10
], where
0 = normal, 1 = slight swelling, 2 = extensive swelling,
and 3 = joint distortion and/or rigidity. The maximum score per
mouse was 12. When killed, the limbs of the mice were removed, fixed,
decalcified, and processed for histological assessment of haematoxylin
and eosin-stained sections, as previously described
[11
].
Detection of Abs to CII by enzyme-linked immunosorbent assay
(ELISA)
ELISAs for Abs to CII were performed as previously described
[11
]. Horseradish peroxidase-conjugated goat anti-mouse
IgG (Sigma) detection Ab was used. Standard curves were constructed
from sera of CII hyperimmunized DBA/1 mice (arbitrarily set at 1000
units/ml).
Statistics
The following statistical tests were used to compare different
groups for the parameters indicated: Mann-Whitney two-sample rank test
(clinical scores), Students t-test for the difference of
two means (anti-CII Ab levels), and the
2 test
(arthritis incidence). For each test, P < 0.05 was
considered statistically significant.
 |
RESULTS
|
|---|
Exogenous M-CSF exacerbates CIA
We previously showed that rhGM-CSF exacerbates CIA in suboptimally
immunized DBA/1 mice when injected at days 2124 postprimary CII
immunization [10
]. Because GM-CSF can affect the
function of cells in the macrophage and granulocyte lineages
[1
] and is also implicated in dendritic cell development
[21
], it was, therefore, of interest to examine the
effects of the lineage-specific CSFs, namely M-CSF and G-CSF, in this
model. Table 1
summarizes data from four experiments, where DBA/1 mice were
suboptimally immunized by i.d. injection of chick CII in CFA, without
boost, and then injected with different doses of M-CSF via the routes
indicated. The M-CSF doses used were based on a previous study
[22
] in which a 10-fold increase in circulating mature
monocytes was obtained in mice given four daily injections of 20 µg
rhM-CSF. The time of administration was according to our previous
studies showing GM-CSF exacerbation of CIA [10
] and is
considered to be at a stage when the mice have an established immune
response to CII but prior to CIA development [23
].
There was a general trend of increased disease severity (clinical
score) in the M-CSF-treated mice for all four experiments (Table 1)
.
Statistical significance was obtained in two experiments (Experiments 1
and 3), where M-CSF potently exacerbated the CIA response in terms of
increased disease incidence and severity. In three other experiments
(unpublished results), M-CSF had no effect; in these experiments, the
control groups generally showed a higher basal level of disease (Table 1
, and unpublished results). The variable response to M-CSF was
independent of the injection regime employed; histological analyses
reflected the clinical assessments (unpublished results). When data
from all seven experiments were combined, there were significantly more
CIA-positive mice in the M-CSF-treated groups (39/69) than in the
control groups (26/68) by day 40 (P<0.05,
2
analysis). The variation observed is unlikely to be a result of
endotoxin contamination in the M-CSF, because this was < 0.1
ng/mg M-CSF (limulus lysate assay). Furthermore, no effect of LPS was
observed, alone or with M-CSF, when CII-immunized mice were given four
daily s.c. injections (days 2023) of M-CSF (15 µg), or vehicle,
with and without the addition of 100 ng LPS (unpublished results).
The kinetics of the enhanced CIA response to M-CSF is shown for
Experiment 3 in Figure 1
, as incidence (A) and clinical score (B). In that experiment, mice
were given four consecutive daily i.p. injections of M-CSF, beginning
20 days postimmunization with CII. It is evident in these suboptimally
immunized mice that, although M-CSF generated an earlier and more
severe form of CIA compared with the control mice, its effect was not
immediate but delayed, with no notable response occurring until five
days after the initial M-CSF injection. The mean clinical scores peaked
at day 43.

View larger version (17K):
[in this window]
[in a new window]
|
Figure 1. Kinetics of the effect of exogenous M-CSF on CIA incidence and
severity. DBA/1 mice were immunized by i.d. injection of CII in CFA and
20 days later, were given four consecutive daily i.p. injections of
M-CSF (30 µg) or the same volume of vehicle (n=10 mice per
group). Mice were assessed and scored for clinical signs of arthritis,
as described in Materials and Methods. The maximum clinical score per
mouse was 12. Results show the percent cumulative incidence (A) and
mean ± SEM clinical scores (B) of the two groups of
mice up to day 60. The average clinical scores of the M-CSF-treated
mice were significantly greater than for the vehicle-treated mice
over the 2160-day period (P<0.005).
|
|
Requirement for endogenous M-CSF in CIA
The above data showed that in some experiments M-CSF could
exacerbate suboptimum CIA. By analogy with our previous studies in
which GM-CSF exacerbated suboptimum CIA [10
], and GM-CSF
deficiency prevented disease [11
], it was reasoned that
endogenous M-CSF may also play a role in conventional CIA. To address
this, the effect of neutralizing mAb to M-CSF on established CIA was
investigated. This time, DBA/1 mice were immunized for optimum
induction of CIA by primary and boost injections with CII in CFA, as
previously described [11
], and given 10 daily injections
of neutralizing mAb to M-CSF (5A1) or isotype-control mAb (DX48),
beginning the first day of onset of arthritis for each individual
mouse. Figure 2
shows that anti-M-CSF mAb alleviated the clinical severity of CIA
established in mice after day 27. Similar results were obtained in a
second experiment.

View larger version (25K):
[in this window]
[in a new window]
|
Figure 2. Neutralizing mAbs to M-CSF reduce the severity of established CIA.
DBA/1 mice were immunized by i.d. injection of CII in CFA at days 0 and
21. Mice were clinically assessed daily for signs of arthritis, and
from day 27 onward, newly arthritic animals (shown as day 1 of
arthritis) were assigned to one of two mAb-treatment groupsanti-M-CSF
(5A1) or isotype control (DX48). Each group received 10 consecutive
daily i.p. injections of mAb (300 µg per day), beginning the first
day of arthritis symptoms. Results show the mean ±
SEM (n=10 mice per group) clinical scores of the
two groups of mice over the first 11 days of CIA. The
anti-M-CSF-treated group had significantly lower clinical scores than
the control group over the 47-day period (P<0.05).
|
|
To further assess the role of endogenous M-CSF in CIA, M-CSF-deficient
mice (op/op) and their wild-type controls were compared for
their responses in the CIA model. Our previous studies
[11
] have shown that, with appropriate protocols, CIA of
high incidence and severity can be induced in mice of non-DBA/1
background, including the background strain of the op/op
mouse (i.e., C57BL/6xC3HeB/FeJ) [24
]. Therefore,
op/op and wild-type control mice were immunized by i.d.
injection with a single dose of CII in CFA, and optimum CIA onset was
accelerated by daily injection (days 2124) into the rear footpad with
IL-1ß, as previously described for DBA/1 mice [20
].
IL-1ß caused only mild transient swelling in the injected paws of the
op/op mice, which was completely resolved by day 29. In
contrast, the wild-type mice exhibited significantly more severe
arthritis (increased paw swelling and clinical score, see Table 2
), which persisted beyond day 29 (five of eight mice), progressing
to joint stiffening and the involvement of other noninjected paws. In
conclusion, the op/op mice were relatively resistant to the
induction of arthritis by IL-1 enhancement of CIA, consistent with the
neutralizing mAb studies (above) indicating a requirement for M-CSF in
CIA development.
Exogenous G-CSF exacerbates CIA
The effect on CIA of administration of the other lineage-specific
CSF, G-CSF, was also examined. Suboptimally stimulated DBA/1 mice were
given four consecutive daily injections (days 1823) with different
doses of G-CSF (Table 3
). The effect of G-CSF was dose-dependent (see Experiment 1, Table 3
), and in contrast to M-CSF, G-CSF (30 µg) consistently elicited a
strong response in each of three experiments. When data from the three
experiments were combined, there were significantly more CIA-positive
mice at day 38 in the G-CSF-treated groups (30 µg) (27/30) compared
with the control groups (15/30; P=0.001,
2
analysis). Therefore, G-CSF increased the incidence and severity of
CIA. Figure 3
shows the kinetics of the G-CSF effect on CIA incidence (A) and
severity (B) (Experiment 3 from Table 3
). Again, in contrast to M-CSF,
the effect of G-CSF was rapid (within 2 days of the first G-CSF
injection), and the mean clinical score peaked earlier (day 27).

View larger version (20K):
[in this window]
[in a new window]
|
Figure 3. Kinetics of the effect of exogenous G-CSF on CIA incidence and
severity. DBA/1 mice were immunized by i.d. injection of CII in CFA and
20 days later, were given four consecutive daily i.p. injections of
G-CSF (30 µg) or the same volume of vehicle (n=10 mice per
group). Mice were assessed and scored for clinical signs of arthritis,
as described in Materials and Methods. Results show the percent
cumulative incidence (A) and mean ± SEM clinical
scores (B) of the two groups of mice up to day 60. The average clinical
scores of the G-CSF-treated mice were significantly greater than for
the vehicle-treated mice over the 2160-day period
(P<0.005).
|
|
Humoral response to CII in M-CSF- and G-CSF-treated mice
The humoral response to CII is an important component of CIA
development in mice [24
25
26
]. The anti-CII IgG sera
levels of mice treated with M-CSF (Experiment 3 from Table 1
) or G-CSF
(Experiment 3 from Table 3
) were, therefore, examined to determine
whether these correlated with the increased CIA incidence and severity
observed in CSF-treated mice compared with controls. Figure 4
shows that the anti-CII IgG levels of the M-CSF-treated, but not
the G-CSF-treated, mice were higher at day 26 and day 60 timepoints,
compared with the corresponding controls.

View larger version (20K):
[in this window]
[in a new window]
|
Figure 4. Effect of M-CSF and G-CSF on serum anti-CII IgG levels. In two separate
experiments (A and B), DBA/1 mice were immunized by i.d. injection of
CII in CFA, as described in Materials and Methods, without boost. At
days 2023, mice (n=10) were injected daily i.p. with 30
µg of M-CSF or G-CSF, or with vehicle (control). Sera were prepared
from blood collected at 26 and 60 days postimmunization and assayed for
anti-CII IgG levels by ELISA. *P < 0.05 compared with
vehicle control.
|
|
 |
DISCUSSION
|
|---|
The CSFs are recognized as regulators of haemopoietic cell
proliferation, differentiation, and survival and more recently as
potent activators of mature haemopoietic cell function
[1
, 2
]. Our previous studies have shown
that the nonlineage-specific CSF, GM-CSF, can exacerbate CIA
[10
] and that GM-CSF-deficient mice are protected from
developing CIA [11
], suggesting a role for this cytokine
in inflammatory autoimmune arthritis. Because GM-CSF can affect cells
of the myeloid and granulocyte lineages [1
], and each is
thought to be involved in CIA [27
], we examined the
effects of the lineage-specific CSFs, M-CSF and G-CSF, in this model.
We found that M-CSF and G-CSF can similarly exacerbate suboptimum CIA.
Interestingly, the effect of G-CSF on CIA was more immediate and
consistent than that of M-CSF (cf. Figs. 1 and 3
). The ability of
myeloid and granulocyte lineage-specific CSFs to exacerbate CIA
suggests that the potent effect of GM-CSF previously demonstrated on
CIA [10
] could mean that it involves the coordinated
actions of more than one cell lineage. This study provides further
support for the idea that the CSFs can have a proinflammatory function
and so may be suitable targets for therapeutic intervention in RA.
The requirement for endogenous M-CSF for CIA was demonstrated by a
reduction in the severity of established disease by M-CSF-neutralizing
mAb (Fig. 2)
and by the resistance of M-CSF-deficient
(op/op) mice to arthritis development (Table 2)
. M-CSF could
be functioning in CIA through effects on monocyte-macrophage
infiltration into the joints, on type-A synovial lining (macrophage
lineage) cells, or on osteoclasts [28
]. Because
administration of rhM-CSF at the doses used in this study elicits up to
a 10-fold increase in circulating blood monocyte levels in mice
[22
], this, in turn, could result in increased numbers
of monocytes/macrophages entering the joint. The importance of
monocyte/macrophage infiltrate in CIA has been demonstrated by the
requirement for macrophage migration inhibitory factor (MIF) function
in the model [29
] and by the prevention of adoptive
transfer of CIA by Mac-1 blockade [30
]. Enhanced numbers
of activated macrophages are present in the synovium at the earliest
preclinical stages of CIA [27
] and are an important
source of cytokines for disease development [31
,
32
]. In addition, macrophages may function as
antigen-presenting cells for CII [33
].
The absence of CIA in op/op mice (Table 2)
possibly provides
support for the importance of the type-A synovial lining cells in this
model. Although op/op mice have normal T-cell-dependent
immune responses [34
], they lack type-A synovial cells
[28
]; thus, the latter are considered an M-CSF-dependent
cell population. Interestingly, unlike some macrophage populations,
type-A synovial cell deficiency in op/op mice cannot be
overcome by the systemic injection of M-CSF from birth
[28
]. These cells may, therefore, be dependent on local
rather than systemic M-CSF production for their survival and
development. This could be supplied by the fibroblast-like (type B)
synovial cells or chondrocytes, which produce basal levels of M-CSF at
least in vitro [4
, 6
,
35
]. Our findings with the op/op mouse are in
agreement with previous studies in which depletion of type-A cells from
the synovial lining by injection of liposome-encapsulated clodronate
resulted in protection from CIA [36
]. However, the
inability of circulating rhM-CSF to restore type-A synovial cells in
the op/op mouse [28
] suggests that the effect
of exogenous M-CSF on CIA could be at the level of circulating
monocytes/macrophages (see above). In short, the numbers and function
of resident and infiltrating monocyte-macrophage populations could be
affected by M-CSF in CIA [27
]. Finally, M-CSF is
essential for osteoclast production [37
] and function
[28
], and these cells could be contributing to the bone
destruction observed in the late stages of CIA. The osteopetrosis of
the op/op mouse is a direct result of the absence of
osteoclasts in these mice.
A threshold anti-CII IgG response is considered a necessary but alone
insufficient requirement for CIA development [25
,
26
, 38
]. The anti-CII IgG levels of the
M-CSF-treated mice were higher than those of control mice (Fig. 4A)
,
but whether this increase actually contributed toward the exacerbation
of CIA by M-CSF is uncertain. The effect of M-CSF on anti-CII IgG
levels could be through elevated levels of cytokines, such as IL-6,
possibly because of increased numbers of "primed"
monocytes/macrophages capable of producing them
[39
40
41
]. In keeping with previous studies in the
op/op mouse [34
], these mice developed normal
levels of anti-CII IgG (unpublished results), similar to our
observations with the GM-CSF-deficient mouse, which showed resistance
to CIA but a normal humoral response to CII [11
]. The
inability of exogenous G-CSF to modulate anti-CII IgG levels (Fig. 4B)
yet still exacerbate CIA (Table 3
, Experiment 3) suggests that the
threshold Ab level for subsequent disease development was already
achieved, even in these suboptimally immunized mice. Therefore, G-CSF
would appear to enhance disease through a separate process. Further
experimentation is required to clarify the mechanisms involved, but
these observations concur with other studies [42
] in
which it was shown that anti-CII Ab levels do not necessarily correlate
with disease.
Data from various animal models suggest that M-CSF may be a key
mediator of certain autoimmune diseases. The MRL/lpr mouse
has elevated M-CSF serum levels, which precede spontaneous
glomerulonephritis [43
]. Splenic mononuclear phagocytes
of the autoimmune motheaten mouse spontaneously produce M-CSF
[44
] and have an enhanced proliferative capacity
in vitro [45
]. In a rat model of experimental
allergic encephalomyelitis (EAE), spinal chord extracts showed elevated
mRNA expression for M-CSF and c-fms (M-CSF receptor), which correlated
with the clinical incidence of disease [46
]. The present
study extends this list to autoimmune arthritis. Perhaps in support of
our findings, a recent gene-mapping study in B10.RIII x RIIIS/J
mice identified a non-MHC CIA susceptibility gene (Mcia2) on chromosome
3 in the region of the M-CSF locusa region previously linked to EAE
[47
].
This study has also provided evidence that cells of the
granulocytic lineage, specifically neutrophils, are important in CIA.
Only one study has described the effect of G-CSF in an arthritis model
[13
], where it was found that i.v. injection of rhG-CSF
into rats enhanced the passive transfer of arthritis using suboptimal
doses of anti-CII rat sera with an associated induction of peripheral
blood neutrophilia. We have now shown an effect of G-CSF on actively
immunized murine CIA. The effect of G-CSF in the current study could be
a result of an increased number of circulating neutrophils mobilized
from haemopoietic stem cells, an enhanced functional ability of the
neutrophils, and/or enhanced haemopoietic progenitor stem-cell numbers
in the circulation. In vivo administration of G-CSF is known
to cause rapid systemic neutrophilia and haemopoietic stem-cell
mobilization [48
]. G-CSF, when given at the elicitation
but not the priming phase, enhances delayed-type hypersensitivity
possibly through an effect on mononuclear cell recruitment
[49
]. Because mononuclear cells lack G-CSF receptors,
this recruitment occurs indirectly through the granulocytes, possibly
via chemokine production. A similar mechanism could be operating in the
present study. Thus, in addition to a direct effect on granulocyte
levels/activation, there may be an indirect effect on mononuclear cell
recruitment leading to accelerated CIA in the already-CII-primed mice.
As well as monocytes/macrophages and neutrophils, GM-CSF stimulates the
proliferation of eosinophils [1
], and so the latter
cells could also be contributing to the exacerbation of CIA in our
studies with GM-CSF [10
]. However, the absence of
receptors for G-CSF and M-CSF on eosinophils precludes a direct effect
on these granulocytes in the present study.
Several studies have demonstrated arthritis flare in RA patients
following administration of G-CSF for correction of the neutropenia
occurring as a complication of Feltys syndrome
[15
16
17
18
] or as a consequence of drug treatments
[50
]. In view of this, two recent studies have addressed
the safety of G-CSF administration to RA patients for haemopoietic
stem-cell mobilization and subsequent autologous stem-cell
transplantation. In one study [51
], no arthritis flare
was noted, although only low G-CSF doses were used (5 µg/kg), and all
five patients had received corticosteroid treatment before therapy. A
second study described arthritis flare in two of five patients
receiving 10 µg/kg G-CSF, the optimum dose of two doses tested for
satisfactory stem-cell mobilization [52
]. Even higher
doses of G-CSF may be required to adequately mobilize haemopoietic stem
cells in RA patients. We showed that G-CSF doses as low as 0.3 µg per
mouse (10 µg/kg) had detectable effects on CIA severity (Table 3 ,
Experiment 1), observations consistent with the latter study. Our
findings further highlight the need for caution in administering G-CSF
to arthritis patients, particularly if doses beyond 10 µg/kg are to
be considered. Additional studies are required to determine whether
endogenous G-CSF is necessary for CIA development. An approach using
neutralizing Abs to G-CSF and/or G-CSF gene-knockout mice similar to
that described herein for M-CSF and elsewhere for GM-CSF
[11
] would address this.
In summary, we have shown that the lineage-specific CSFs, M-CSF,
and G-CSF can exacerbate CIA, findings supporting roles for
monocytes/macrophages and granulocytes in autoimmune inflammatory
arthritis. We further showed that M-CSF blockade can alleviate disease
and that M-CSF-dependent cells are required for CIA. The presence of
CSFs in rheumatoid joints and their mutual modulation in
vitro by the proinflammatory cytokines, IL-1 and TNF-
, led to
the proposal of a local "CSF network" within joints that might help
explain the chronicity of inflammatory joint disease
[53
]. Together with our previous findings
[10
, 11
], the present study highlights the
potent proinflammatory potential of the CSFs and suggests they may be
targets for therapeutic intervention in rheumatoid disease.
 |
ACKNOWLEDGEMENTS
|
|---|
This work was supported by grants from the NHMRC of Australia and
in part by grants from the Arthritis Foundation of Australia and Amgen.
We thank J. Davis for animal care, Dr. A. Dunn (Ludwig Institute for
Cancer Research) for the supply and maintenance of op/op and
littermate mice, and Dr. F. Kull (Glaxo-Wellcome) for supply of 5A1 and
DX48 mAbs.
 |
FOOTNOTES
|
|---|
Correspondence at current address: Dr. Ian K. Campbell, Reid
Rheumatology Laboratory, Division of Autoimmunity and Transplantation,
The Walter and Eliza Hall Institute of Medical Research, Post Office
Royal Melbourne Hospital, Victoria, 3050, Australia. E-mail: campbell{at}wehi.edu.au
Received November 29, 1999;
revised February 29, 2000;
accepted March 1, 2000.
 |
REFERENCES
|
|---|
-
Metcalf, D. (1991) The Florey Lecture, 1991. The colony-stimulating factors: discovery to clinical use Philos. Trans. R. Soc. Lond. B Biol. Sci. 333,147-173[Medline]
-
Hamilton, J. A., Stanley, E. R., Burgess, A. W., Shadduck, R. K. (1980) Stimulation of macrophage plasminogen activator activity by colony-stimulating factors J. Cell. Physiol. 103,435-445[Medline]
-
Campbell, I. K., Novak, U., Cebon, J., Layton, J. E., Hamilton, J. A. (1991) Human articular cartilage and chondrocytes produce hemopoietic colony-stimulating factors in culture in response to IL-1 J. Immunol. 147,1238-1246[Abstract]
-
Campbell, I. K., Ianches, G., Hamilton, J. A. (1993) Production of macrophage colony-stimulating factor (M-CSF) by human articular cartilage and chondrocytes. Modulation by interleukin-1 and tumour necrosis factor
Biochim. Biophys. Acta 1182,57-63
-
Leizer, T., Cebon, J., Layton, J. E., Hamilton, J. A. (1990) Cytokine regulation of colony-stimulating factor production in cultured human synovial fibroblasts: I. induction of GM-CSF and G-CSF production by interleukin-1 and tumor necrosis factor Blood 76,1989-1996[Abstract/Free Full Text]
-
Hamilton, J. A., Filonzi, E. L., Ianches, G. (1993) Regulation of macrophage colony-stimulating factor (M-CSF) production in cultured human synovial fibroblasts Growth Factors 9,157-165[Medline]
-
Firestein, G., Xu, W-D., Townsend, K., Broide, D., Alvaro-Gracia, J., Glasebrook, A., Zvaifler, N. J. (1988) Cytokines in chronic inflammatory arthritis. I. Failure to detect T cell lymphokines (interleukin 2 and interleukin 3) and presence of macrophage colony-stimulating factor (CSF-1) and a novel mast cell growth factor in rheumatoid synovitis J. Exp. Med. 168,1573-1586[Abstract/Free Full Text]
-
Xu, W. D., Firestein, G. S., Taetle, R., Kaushansky, K., Zvaifler, N. J. (1989) Cytokines in chronic inflammatory arthritis. II. Granulocyte-macrophage colony-stimulating factor in rheumatoid synovial effusions J. Clin. Invest. 83,876-882
-
Alvaro-Gracia, J. M., Zvaifler, N. J., Brown, C. B., Kaushansky, K., Firestein, G. S. (1991) Cytokines in chronic inflammatory arthritis. VI. Analysis of the synovial cells involved in granulocyte-macrophage colony-stimulating factor production and gene expression in rheumatoid arthritis and its regulation by IL-1 and tumor necrosis factor-
J. Immunol. 146,3365-3371[Abstract]
-
Campbell, I. K., Bendele, A., Smith, D. A., Hamilton, J. A. (1997) Granulocyte-macrophage colony stimulating factor exacerbates collagen induced arthritis in mice Ann. Rheum. Dis. 56,364-368[Abstract/Free Full Text]
-
Campbell, I. K., Rich, M. J., Bischof, R. J., Dunn, A. R., Grail, D., Hamilton, J. A. (1998) Protection from collagen-induced arthritis in granulocyte-macrophage colony-stimulating factor-deficient mice J. Immunol. 161,3639l-33644
-
Abd, A-H. A., Savage, N. W., Halliday, W. J., Hume, D. A. (1991) The role of macrophages in experimental arthritis induced by Streptococcus agalactiae sonicate: actions of macrophage colony-stimulating factor (CSF-1) and other macrophage-modulating agents Lymphokine Cytokine Res 10,43-50[Medline]
-
Miyahara, H., Hotokebuchi, T., Saikawa, I., Arita, C., Takagishi, K., Sugioka, Y. (1993) The effects of recombinant human granulocyte colony-stimulating factor on passive collagen-induced arthritis transferred with anti-type II collagen antibody Clin. Immunol. Immunopathol. 69,69-76[Medline]
-
Fraser, D. D., Sartiano, G. P., Butler, T. W., Treadwell, E. L. (1993) Neutropenia of Feltys syndrome successfully treated with granulocyte colony stimulating factor J. Rheumatol. 20,1447-1448[Medline]
-
Hayat, S. Q., Hearth-Holmes, M., Wolf, R. E. (1995) Flare of arthritis with successful treatment of Feltys syndrome with granulocyte colony stimulating factor Clin. Rheumatol. 14,211-212[Medline]
-
McMullin, M. F., Finch, M. B. (1995) Feltys syndrome treated with rhG-CSF associated with flare of arthritis and skin rash Clin. Rheumatol. 14,204-208[Medline]
-
Vidarsson, B., Geirsson, A. J., Onundarson, P. T. (1995) Reactivation of rheumatoid arthritis and development of leukocytoclastic vasculitis in a patient receiving granulocyte colony-stimulating factor for Feltys syndrome Am. J. Med. 98,589-591[Medline]
-
Yasuda, M., Kihara, T., Wada, T., Shiokawa, S., Furuta, E., Suenagu, Y., Nonaka, S., Nobunaga, M., Yoshioka, K., Isayama, T. (1994) Granulocyte colony-stimulating factor induction of improved leukocytopenia with inflammatory flare in a Feltys syndrome patient Arthritis Rheum 37,145-146[Medline]
-
Cooley, H. M., Snowden, J. A., Grigg, A. P., Wicks, I. P. (1997) Outcome of rheumatoid arthritis and psoriasis following autologous stem cell transplantation for hematologic malignancy Arthritis Rheum 40,1712-1715[Medline]
-
Killar, L. M., Dunn, C. J. (1989) Interleukin-1 potentiates the development of collagen-induced arthritis in mice Clin. Sci. 76,535-538[Medline]
-
Inaba, K., Inaba, M., Romani, N., Aya, H., Deguchi, M., Ikehara, S., Muramatsu, S., Steinman, R. M. (1992) Generation of large numbers of dendritic cells from mouse bone marrow cultures supplemented with granulocyte/macrophage colony-stimulating factor J. Exp. Med. 176,1693-1702[Abstract/Free Full Text]
-
Hume, D. A., Pavli, P., Donahue, R. E., Fidler, I. J. (1988) The effect of human recombinant macrophage colony-stimulating factor (CSF-1) on the murine mononuclear phagocyte system in vivo J. Immunol. 141,3405-3409[Abstract]
-
Wooley, P. H. (1988) Collagen-induced arthritis in the mouse Methods Enzymol 162,361-373[Medline]
-
Campbell, I. K., Hamilton, J. A., Wicks, I. P. Collagen-induced arthritis in C57BL/6 (H-2b) mice: new insights into an important disease model of rheumatoid arthritis. Eur. J. Immunol., in press.
-
Seki, N., Sudo, Y., Yoshioka, T., Sugihara, S., Fujitsu, T., Sakuma, S., Ogawa, T., Hamaoka, T., Senoh, H., Fujiwara, H. (1988) Type II collagen-induced murine arthritis. I. Induction and perpetuation of arthritis require synergy between humoral and cell-mediated immunity J. Immunol. 140,1477-1484[Abstract]
-
Wooley, P. H., Luthra, H. S., Stuart, J. M., David, C. S. (1981) Type II collagen-induced arthritis in mice. I. Major histocompatibility complex (I region) linkage and antibody correlates J. Exp. Med. 154,688-700[Abstract/Free Full Text]
-
Holmdahl, R., Tarkowski, A., Jonsson, R. (1991) Involvement of macrophages and dendritic cells in synovial inflammation of collagen induced arthritis in DBA/1 mice and spontaneous arthritis in MRL/Lpr mice Autoimmunity 8,271-280[Medline]
-
Cecchini, M. G., Dominguez, M. G., Mocci, S., Wetterwald, A., Felix, R., Fleisch, H., Chisholm, O., Hofstetter, W., Pollard, J. W., Stanley, E. R. (1994) Role of colony stimulating factor-1 in the establishment and regulation of tissue macrophage during postnatal development of the mouse Development 120,1357-1372[Abstract]
-
Mikulowska, A., Metz, C. N., Bucala, R., Holmdahl, R. (1997) Macrophage migration inhibitory factor is involved in the pathogenesis of collagen type II-induced arthritis in mice J. Immunol. 158,5514-5517[Abstract]
-
Taylor, P., Chu, C., Plater-Zyberk, C., Maini, R. (1996) Transfer of type II collagen-induced arthritis from DBA/1 to severe combined immunodeficiency mice can be prevented by blockade of Mac-1 Immunology 88,315-321[Medline]
-
Marinova-Mutafchieva, L., Williams, R. O., Mason, L. J., Mauri, C., Feldmann, M., Maini, R. N. (1997) Dynamics of proinflammatory cytokine expression in the joints of mice with collagen-induced arthritis (CIA) Clin. Exp. Immunol. 107,507-512[Medline]
-
Müssener, Å., Litton, M. J., Lindroos, E., Klareskog, L. (1997) Cytokine production in synovial tissue of mice with collagen-induced arthritis (CIA) Clin. Exp. Immunol. 107,485-493[Medline]
-
Michaëlsson, E., Holmdahl, M., Engström, Å., Burkhardt, H., Scheynius, A., Holmdahl, R. (1995) Macrophages, but not dendritic cells, present collagen to T cells Eur. J. Immunol. 25,2234-2241[Medline]
-
Chang, M-D. Y., Stanley, E. R., Khalili, H., Chischolm, O., Pollard, J. W. (1995) Osteopetrotic (op/op) mice deficient in macrophages have the ability to mount a normal T-cell-dependent immune response Cell. Immunol. 162,146-152[Medline]
-
Seitz, M., Loetscher, P., Fey, M. F., Tobler, A. (1994) Constitutive mRNA and protein production of macrophage colony-stimulating factor but not of other cytokines by synovial fibroblasts from rheumatoid arthritis and osteoarthritis patients Br. J. Rheumatol. 33,613-619[Abstract/Free Full Text]
-
van Lent, P. L. E. M., Holthuysen, A. E. M., van den Bersselaar, L. A. M., van Rooijen, N., Joosten, L. A. B., van de Loo, F. A. J., van de Putte, L. B. A., van den Berg, W. B. (1996) Phagocytic lining cells determine local expression of inflammation in type II collagen-induced arthritis Arthritis Rheum 39,1545-1555[Medline]
-
Tanaka, S., Takahashi, N., Udagawa, N., Tamura, T., Akatsu, T., Stanley, E. R., Kurokawa, T., Suda, T. (1993) Macrophage colony-stimulating factor is indispensable for both proliferation and differentiation of osteoclast progenitors J. Clin. Invest. 91,257-263
-
Watson, W. C., Townes, A. (1985) Genetic susceptibility to murine collagen II autoimmune arthritis. Proposed relationship to the IgG2 autoantibody subclass response, complement C5, major histocompatibility complex (MHC) and non-MHC loci J. Exp. Med. 162,1878-1891[Abstract/Free Full Text]
-
Hamilton, J. A. (1993) Colony stimulating factors, cytokines and monocyte-macrophagessome controversies Immunol. Today 14,18-24[Medline]
-
Kamdar, S. J., Chapoval, A. I., Phelps, J., Fuller, J. A., Evans, R. (1996) Differential sensitivity of mouse mononuclear phagocytes to CSF-1 and LPS: the potential in vivo relevance of enhanced IL-6 gene expression Cell. Immunol. 174,165-172[Medline]
-
Evans, R., Kamdar, S. J., Fuller, J. A., Krupke, D. M. (1995) The potential role of the macrophage colony-stimulating factor, CSF-1, in inflammatory responses: characterization of macrophage cytokine gene expression J. Leuk. Biol. 58,99-107[Abstract]
-
Ranges, G. E., Sriram, S., Cooper, S. M. (1985) Prevention of type II collagen-induced arthritis by in vivo treatment with anti-L3T4 J. Exp. Med. 162,1105-1110[Abstract/Free Full Text]
-
Yui, M. A., Brissette, W. H., Brennan, D. C., Wuthrich, R. P., Rubin-Kelley, V. E. (1991) Increased macrophage colony-stimulating factor in neonatal and adult autoimmune MRL-lpr mice Am. J. Pathol. 139,255-261[Abstract]
-
McCoy, K. L., Nielson, K., Clagett, J. (1984) Spontaneous production of colony-stimulating activity by splenic Mac-1 antigen-positive cells from autoimmune motheaten mice J. Immunol. 132,272-276[Abstract]
-
McCoy, K. L., Chi, E., Engel, D., Rosse, C., Clagett, J. (1982) Abnormal in vitro proliferation of splenic mononuclear phagocytes from autoimmune motheaten mice J. Immunol. 128,1797-1804[Abstract]
-
Hulkower, K., Brosnan, C. F., Aquino, D. A., Cammer, W., Kulshrestha, S., Guida, M. P., Rapoport, D. A., Berman, J. W. (1993) Expression of CSF-1, c-fms, and MCP-1 in the central nervous system of rats with experimental allergic encephalomyelitis J. Immunol. 150,2525-2533[Abstract]
-
Jirholt, J., Cook, A., Emahazion, T., Sundvall, M., Jansson, L., Nordquist, N., Pettersson, U., Holmdahl, R. (1998) Genetic linkage analysis of collagen-induced arthritis in the mouse Eur. J. Immunol. 28,3321-3328[Medline]
-
Grigg, A. P., Roberts, A. W., Raunow, H., Houghton, S., Layton, J. E., Boyd, A. W., McGrath, K. M., Maher, D. (1995) Optimizing dose and scheduling of filgrastim (granulocyte colony-stimulating factor) for mobilization and collection of peripheral blood progenitor cells in normal volunteers Blood 86,4437-4445[Abstract/Free Full Text]
-
Terashita, M., Kudo, C., Yamashita, T., Gresser, I., Sendo, F. (1996) Enhancement of delayed-type hypersensitivity to sheep red blood cells in mice by granulocyte colony-stimulating factor administration at the elicitation phase J. Immunol. 156,4638-4643[Abstract]
-
Nakashima, H., Kawabe, K., Ohtsuka, T., Hayashida, K., Horiuchi, T., Nagasawa, K., Niho, Y. (1995) Rheumatoid arthritis exacerbation by G-CSF treatment for bucillamine induced agranulocytosis Clin. Exp. Rheumatol. 13,677-679[Medline]
-
McGonagle, D., Rawstron, A., Richards, S., Isaacs, J., Bird, H., Jack, A., Morgan, G., Emery, P. (1997) A phase 1 study to address the safety and efficacy of granulocyte colony-stimulating factor for the mobilization of hematopoietic progenitor cells in active rheumatoid arthritis Arthritis Rheum 40,1838-1842[Medline]
-
Snowden, J. A., Biggs, J. C., Milliken, S. T., Fuller, A., Staniforth, D., Passuello, F., Renwick, J., Brooks, P. M. (1998) A randomised, blinded, placebo-controlled, dose escalation study of the tolerability and efficacy of filgrastim for haemopoietic stem cell mobilisation in patients with severe active rheumatoid arthritis Bone Marrow Transpl 22,1035-1041
-
Hamilton, J. A. (1993) Rheumatoid arthritis: opposing actions of haemopoietic growth factors and slow-acting anti-rheumatic drugs Lancet 342,536-539[Medline]
This article has been cited by other articles:

|
 |

|
 |
 
J. G. Conway, H. Pink, M. L. Bergquist, B. Han, S. Depee, S. Tadepalli, P. Lin, R. C. Crumrine, J. Binz, R. L. Clark, et al.
Effects of the cFMS Kinase Inhibitor 5-(3-Methoxy-4-((4-methoxybenzyl)oxy)benzyl)pyrimidine-2,4-diamine (GW2580) in Normal and Arthritic Rats
J. Pharmacol. Exp. Ther.,
July 1, 2008;
326(1):
41 - 50.
[Abstract]
[Full Text]
[PDF]
|
 |
|

|
 |

|
 |
 
W. Abou-Kheir, B. Isaac, H. Yamaguchi, and D. Cox
Membrane targeting of WAVE2 is not sufficient for WAVE2-dependent actin polymerization: a role for IRSp53 in mediating the interaction between Rac and WAVE2
J. Cell Sci.,
February 1, 2008;
121(3):
379 - 390.
[Abstract]
[Full Text]
[PDF]
|
 |
|

|
 |

|
 |
 
C. Schalk-Hihi, H.-C. Ma, G. T. Struble, S. Bayoumy, R. Williams, E. Devine, I. P. Petrounia, T. Mezzasalma, L. Zeng, C. Schubert, et al.
Protein Engineering of the Colony-stimulating Factor-1 Receptor Kinase Domain for Structural Studies
J. Biol. Chem.,
February 9, 2007;
282(6):
4085 - 4093.
[Abstract]
[Full Text]
[PDF]
|
 |
|

|
 |

|
 |
 
C. Schubert, C. Schalk-Hihi, G. T. Struble, H.-C. Ma, I. P. Petrounia, B. Brandt, I. C. Deckman, R. J. Patch, M. R. Player, J. C. Spurlino, et al.
Crystal Structure of the Tyrosine Kinase Domain of Colony-stimulating Factor-1 Receptor (cFMS) in Complex with Two Inhibitors
J. Biol. Chem.,
February 9, 2007;
282(6):
4094 - 4101.
[Abstract]
[Full Text]
[PDF]
|
 |
|

|
 |

|
 |
 
S. Wei, X.-M. Dai, and E. R. Stanley
Transgenic expression of CSF-1 in CSF-1 receptor-expressing cells leads to macrophage activation, osteoporosis, and early death
J. Leukoc. Biol.,
December 1, 2006;
80(6):
1445 - 1453.
[Abstract]
[Full Text]
[PDF]
|
 |
|

|
 |

|
 |
 
K. M. Irvine, C. J. Burns, A. F. Wilks, S. Su, D. A. Hume, and M. J. Sweet
A CSF-1 receptor kinase inhibitor targets effector functions and inhibits pro-inflammatory cytokine production from murine macrophage populations
FASEB J,
September 1, 2006;
20(11):
1921 - 1923.
[Abstract]
[Full Text]
[PDF]
|
 |
|

|
 |

|
 |
 
J. C. Scatizzi, J. Hutcheson, E. Bickel, J. M. Woods, K. Klosowska, T. L. Moore, G. K. Haines III, and H. Perlman
p21Cip1 Is Required for the Development of Monocytes and Their Response to Serum Transfer-induced Arthritis
Am. J. Pathol.,
May 1, 2006;
168(5):
1531 - 1541.
[Abstract]
[Full Text]
[PDF]
|
 |
|

|
 |

|
 |
 
S. Nandi, M. P. Akhter, M. F. Seifert, X.-M. Dai, and E. R. Stanley
Developmental and functional significance of the CSF-1 proteoglycan chondroitin sulfate chain
Blood,
January 15, 2006;
107(2):
786 - 795.
[Abstract]
[Full Text]
[PDF]
|
 |
|

|
 |

|
 |
 
S. Rutella, F. Zavala, S. Danese, H. Kared, and G. Leone
Granulocyte Colony-Stimulating Factor: A Novel Mediator of T Cell Tolerance
J. Immunol.,
December 1, 2005;
175(11):
7085 - 7091.
[Abstract]
[Full Text]
[PDF]
|
 |
|

|
 |

|
 |
 
W. Abou Kheir, J.-C. Gevrey, H. Yamaguchi, B. Isaac, and D. Cox
A WAVE2-Abi1 complex mediates CSF-1-induced F-actin-rich membrane protrusions and migration in macrophages
J. Cell Sci.,
November 15, 2005;
118(22):
5369 - 5379.
[Abstract]
[Full Text]
[PDF]
|
 |
|

|
 |

|
 |
 
J. G. Conway, B. McDonald, J. Parham, B. Keith, D. W. Rusnak, E. Shaw, M. Jansen, P. Lin, A. Payne, R. M. Crosby, et al.
Inhibition of colony-stimulating-factor-1 signaling in vivo with the orally bioavailable cFMS kinase inhibitor GW2580
PNAS,
November 1, 2005;
102(44):
16078 - 16083.
[Abstract]
[Full Text]
[PDF]
|
 |
|

|
 |

|
 |
 
K. E. Lawlor, I. K. Campbell, D. Metcalf, K. O'Donnell, A. van Nieuwenhuijze, A. W. Roberts, and I. P. Wicks
Critical role for granulocyte colony-stimulating factor in inflammatory arthritis
PNAS,
August 3, 2004;
101(31):
11398 - 11403.
[Abstract]
[Full Text]
[PDF]
|
 |
|

|
 |

|
 |
 
R. A. Nash, J. D. Bowen, P. A. McSweeney, S. Z. Pavletic, K. R. Maravilla, M.-s. Park, J. Storek, K. M. Sullivan, J. Al-Omaishi, J. R. Corboy, et al.
High-dose immunosuppressive therapy and autologous peripheral blood stem cell transplantation for severe multiple sclerosis
Blood,
October 1, 2003;
102(7):
2364 - 2372.
[Abstract]
[Full Text]
[PDF]
|
 |
|

|
 |

|
 |
 
D. M. Lenda, E. Kikawada, E. R. Stanley, and V. R. Kelley
Reduced Macrophage Recruitment, Proliferation, and Activation in Colony-Stimulating Factor-1-Deficient Mice Results in Decreased Tubular Apoptosis During Renal Inflammation
J. Immunol.,
March 15, 2003;
170(6):
3254 - 3262.
[Abstract]
[Full Text]
[PDF]
|
 |
|

|
 |

|
 |
 
A. Chakraborty, E. R. Hentzen, S. M. Seo, and C. W. Smith
Granulocyte colony-stimulating factor promotes adhesion of neutrophils
Am J Physiol Cell Physiol,
January 1, 2003;
284(1):
C103 - C110.
[Abstract]
[Full Text]
[PDF]
|
 |
|

|
 |

|
 |
 
A. D. Cook, E. L. Braine, I. K. Campbell, and J. A. Hamilton
Differing Roles for Urokinase and Tissue-Type Plasminogen Activator in Collagen-Induced Arthritis
Am. J. Pathol.,
March 1, 2002;
160(3):
917 - 926.
[Abstract]
[Full Text]
[PDF]
|
 |
|