| HOME | HELP | FEEDBACK | SUBSCRIPTIONS | ARCHIVE | SEARCH | TABLE OF CONTENTS |
|
|
|
|||||||
|
|||||||||
*
Pulmonary and Critical Care Division, Department of Medicine, Hospital of University of Pennsylvania, Philadelphia, PA 19104;
Immunex Corporation, Seattle, WA 98101; and
The Wistar Institute, Philadelphia, PA 19104
 |
Abstract |
|---|
 Top Abstract IntroductionMaterials and MethodsResultsDiscussionReferences |
|---|
or IFN-
. Cross-linking CD40 on ASM resulted
in enhanced IL-6 secretion and an increase in intracellular calcium
concentrations, which were dependent on calcium influx. We show that
CD40-mediated signaling events include protein tyrosine phosphorylation
and activation of NF-
B. Pretreatment of ASM with the tyrosine kinase
inhibitors genistein or herbimycin inhibited the rapid mobilization of
calcium induced via CD40, suggesting that calcium mobilization was
coupled to activation of protein tyrosine kinases. In addition,
inhibition of calcium influx inhibited both CD40-mediated NF-B
activation and enhancement of IL-6 secretion. These results delineate a
potentially important CD40-mediated signal-transduction pathway in ASM,
involving protein tyrosine kinase-dependent calcium mobilization,
NF-B activation, and IL-6 production. Together, these results
suggest a mechanism whereby T cell/smooth muscle cell interactions may
potentiate airway inflammation. |
Introduction |
|---|
|
TopAbstractIntroductionMaterials and MethodsResultsDiscussionReferences |
|---|
CD40 is also constitutively expressed on a variety of other
leukocytes, such as macrophages (18), dendritic cells (19), and
eosinophils (20), and on the surface of cells of mesenchymal and
epithelial origin, such as endothelial cells (21, 22, 23), fibroblasts (24, 25), keratinocytes (26, 27), and vascular smooth muscle cells (28). On
mesenchymal cells, where CD40 is inducible by cytokines such as
IFN-, engagement of CD40 has been reported to lead to up-regulation
of costimulatory and cell adhesion molecules (22, 23, 24), secretion of
proinflammatory cytokines (24, 25, 27, 28, 29), and effects on cellular
proliferation (24, 26), although the mechanisms of such signaling are
currently unknown. These data support a widespread role for CD40 in the
inflammatory response.
We are interested in the potential role of leukocyte/smooth
muscle cell interactions in the context of airway inflammation. We
previously demonstrated that activated T cell-derived cytokines
up-regulated expression of HLA-DR and ICAM-1 on ASM (30) and that the
exposure to the inflammatory cytokine TNF- augmented the sensitivity
of ASM to a variety of contractile agonists (31, 32). In addition to
soluble mediators, however, we previously showed that activated T cells
adhered to ASM via integrins and CD44 and induced ASM DNA synthesis in
a contact-dependent manner (33). These data suggest that T cell-ASM
interactions most likely play a potentially important role in cellular
recruitment and airway inflammation in diseases such as asthma.
One interesting feature of CD40-mediated signaling is that it is contact dependent, requiring adhesion of the CD40L-positive activated T cell to the surface of the CD40-positive target cells. Because engagement of CD40 on endothelial cells and fibroblasts resulted in a number of changes that are relevant to inflammation, we hypothesized that ASM might also express CD40 and that this molecule might serve as an important signal-transduction molecule with regard to activated lymphocyte-ASM interactions. Accordingly, we analyzed the expression of CD40 on human airway smooth muscle cells and its regulation by cytokines, examined the functional consequences of receptor engagement by CD40L or anti-CD40 mAb by measuring ASM cytosolic calcium and cytokine secretion, and identified several early signaling events induced by ligation of CD40 on ASM.
|
Materials and Methods |
|---|
|
TopAbstractIntroductionMaterials and MethodsResultsDiscussionReferences |
|---|
5C3 (anti-human CD40) was purchased from PharMingen (San
Diego, CA); trimerized human CD40L (CD40LT) was produced as previously
described (34); 4G10 (anti-phosphotyrosine) was purchased from
Upstate Biotechnology (Lake Placid, NY). TNF- was purchased from
Boehringer Mannheim (Indianapolis, IN); IFN- was purchased from
PharMingen.
Cell culture
Human airway smooth muscle was obtained from the trachealis muscle of lung transplant donors in accordance with the policies of the Committee on Studies Involving Human Beings at University of Pennsylvania (Philadelphia, PA). ASM cells were purified as previously described (35) and cultured in Ham’s F12 supplemented with penicillin, streptomycin, glutamine, HEPES, and 10% heat-inactivated FBS. The results reported are representative of those obtained with a minimum of three different smooth muscle cell lines. Characterization of the cultured smooth muscle, including staining for smooth muscle-specific actin and responsiveness to contractile agonists, has been previously described (35).
Flow cytometry
Confluent ASM in 12-well plates were incubated with media alone or with cytokines for 24 to 72 h. The monolayers were washed, and then single cell suspensions were prepared using 5 mM EDTA. Cells were stained with Abs specific for human CD40, followed by FITC-conjugated goat anti-mouse IgG (Jackson ImmunoResearch, West Grove, PA), and analyzed using a FACScan (Becton Dickinson, San Jose, CA) and CellQuest software.
IL-6 determination
Confluent ASM were treated with either TNF- or IFN-. After
72 h, the monolayers were washed and supplied with fresh media,
and soluble CD40LT (10 µg/ml) was then added to the indicated wells.
The plates were incubated for an additional 24 h, at which time
the supernatants were collected and frozen at -80°C until cytokine
assays were performed. Human IL-6 was quantitated using a commercial
ELISA (R&D Systems, Minneapolis, MN), according to the manufacturer’s
instructions. Statistical differences in IL-6 production were
calculated using a nonparametric matched-pair analysis. Values of
p < 0.05 were considered statistically significant.
Immunoblotting
Confluent ASM cells were rendered quiescent by culturing in serum-free media for 24 h, then stimulated with 2 µg/ml anti-CD40 for the times indicated. Cells were lysed in buffer containing 50 mM Tris, pH 7.5, 100 mM NaCl, 1% Triton X-100, 0.1% deoxycholate, 100 µg/ml leupeptin, 1 mM PMSF, 10 µg/ml aprotinin, 5 mM EDTA, 50 mM NaF, 40 mM ß-glycerophosphate, and 1 mM Na3VO4 for 10 min at 4°C. Postnuclear extracts were obtained by centrifugation of lysates at 14,000 x g for 10 min. Equivalent amounts of protein, as determined by the bicinchoninic acid (BCA) protein assay kit (Pierce, Rockford, IL), were resolved on an 8% SDS-polyacrylamide gel under reducing conditions, transferred to polyvinylidene difluoride (PVDF) membranes, and blocked in a solution containing 30 mM Tris, pH 7.6, 75 mM NaCl, and 3% BSA. Membranes were immunoblotted with anti-phosphotyrosine for 1 h at 4°C, followed by rabbit anti-mouse IgG (Jackson ImmunoResearch). Bound Ab was detected using 125I-labeled protein A (DuPont NEN, Boston, MA) and visualized by autoradiography.
Cytosolic calcium measurements
ASM cells were plated at low density onto 15-mm coverslips 3 to 5 days before the experiments were performed. All experiments were performed using subconfluent cells between third and fifth passage. Cells were loaded with 2.5 mM fura-2/AM (in HEPES buffer containing 137.5 mM NaCl, 1.25 mM CaCl2, 1.25 mM MgCl2, 0.4 mM NaHPO4, 6 mM KCl, 5.6 mM glucose, supplemented with 1 mg/ml BSA) for 30 min at 37°C, and washed in HEPES-buffered saline. Cells were then placed in a thermostatically controlled cell chamber on a Nikon inverted microscope (Diaphot). Cells were imaged using a x40 (oil) fluorescence objective lens. Excitation energy was switched between 340 and 380 nm wavelength using a 75 W xenon lamp source and a fura-2 dichroic mirror (Chroma Technology, Brattleboro, VT). The emitted fluorescence (510 nm) was diverted to an image-intensified CCD camera (Hamamatsu, Hamamatsu City, Japan) attached to the video analogue-to-port digital conversion board (Maatrox). Image analysis of individual cells was accomplished using the Image-1 AT/Fluor program (Universal Imaging, West Chester, PA). The 340/380 ratio was converted to an estimate of cytosolic free calcium using previously described methods (36, 37). Calibration measurements were made by treating cells with ionomycin (10 mM) in the presence of 12 mM calcium to measure Rmax, or by adding a stoichiometric excess of EGTA to achieve Rmin. Values used for the calibration equation were Rmin = 0.3 and Rmax = 0.6, Kd = 224 and f380min/f380max = 5. Abs or soluble ligand were added directly to the bath. Bradykinin (1 mM; Sigma, St. Louis, MO) was added to compare the magnitude of bradykinin-induced calcium transients with those evoked by CD40. NiCl2 (4 mM; Fisher Scientific, Springfield, NJ) or MnCl2 (200 µM; Fisher) was added to distinguish release of calcium from intracellular stores from calcium influx. Where indicated, cells were pretreated with either genistein (5 µM; Life Technologies, Grand Island, NY) for 1 h or herbimycin (10 µM; Sigma) for 4 h at 37°C before stimulation with anti-CD40.
Nuclear extracts and mobility shift assay
Nuclear extracts were prepared according to the method of
Andrews and Faller (38). Confluent ASM were treated with IFN- (500
U/ml) for 72 h, then stimulated with CD40LT (10 µg/ml) for the
indicated times. Cells were harvested by scraping into cold PBS. Nuclei
were isolated by treatment with hypotonic lysis buffer A containing 10
mM HEPES, 10 mM KCl, 1.5 mM MgCl2, 0.5 mM DTT, 0.5 mM PMSF,
1 µg/ml leupeptin, and 0.5% Nonidet P-40. The nuclear pellet was
resuspended in buffer B (420 mM NaCl, 20 mM HEPES, 1.5 mM
MgCl2, 0.2 mM EDTA, 25% glycerol, 0.5 mM DTT, 0.5 mM PMSF,
and 10 µg/ml leupeptin) for 20 min on ice and clarified by
centrifugation at 13,000 x g. The resulting
supernatants contained 1 to 2 mg/ml protein by the bicinchoninic acid
(BCA) assay. Nuclear extracts were stored at -80°C.
A double-stranded oligonucleotide probe containing the NF-B
consensus sequence (Promega, Madison, WI) was end labeled with
[-32P]ATP using T4 kinase (Life Technologies). A total
of 8 µg of nuclear extract was incubated with 1 µg poly(dI-dC) and
radiolabeled probe for 30 min at room temperature. DNA-protein
complexes were resolved by electrophoresis on a 4% nondenaturing
polyacrylamide gel at 200 V. The gels were then dried and exposed to
x-ray film for autoradiography. In supershift experiments, nuclear
extracts were preincubated with polyclonal goat Abs specific for p50,
p65, or c-Rel (Santa Cruz Biotechnology, Santa Cruz, CA) for 15 min on
ice before the addition of 32P-labeled probe.
|
Results |
|---|
|
TopAbstractIntroductionMaterials and MethodsResultsDiscussionReferences |
|---|
and
IFN-
To determine whether the interaction between activated T cells and
airway smooth muscle could potentially involve CD40-CD40L binding, we
examined whether human ASM expressed CD40. Unstimulated, cultured human
ASM cells were stained with anti-CD40 Abs and analyzed by flow
cytometry. Low constitutive expression of CD40 was detected compared
with control ASM reacted with an isotype-matched control mAb (Fig. 1
A). Treatment of ASM with
either TNF- or IFN- induced a two- to fourfold increase in CD40
expression (Fig. 1A), and the effect of TNF- and IFN-
together was at least additive, inducing a sevenfold increase in CD40
expression (data not shown). In contrast, IL-4 had no effect or
resulted in a slight decrease in CD40 expression compared with baseline
expression (Fig. 1A), but had no effect on TNF- or
IFN--induced up-regulation of CD40 (data not shown). Maximal
expression of CD40 occurred on day 2 following treatment with TNF-,
and on day 3 following IFN- stimulation (Fig. 1B,
top) and was dose dependent (Fig. 1B,
bottom).
|
We examined whether CD40 triggered cytokine production by ASM by
measuring IL-6 in response to stimulation with soluble CD40LT.
Unstimulated ASM produced low basal levels of IL-6, while treatment
with CD40LT increased IL-6 secretion by approximately 38 ± 9%
(Fig. 2). Stimulation with TNF-
increased IL-6 secretion by approximately 2.7-fold over baseline
values; CD40LT increased TNF--induced IL-6 production by 26 ±
10%. IFN- alone had minimal effects on IL-6 production by ASM, but
acted synergistically with CD40LT, increasing IFN--induced IL-6
secretion by approximately 73 ± 12% compared with IFN- alone
(Fig. 2). These data suggest that CD40-CD40L interactions can transduce
a costimulatory activation signal leading to the augmented release of
inflammatory mediators by ASM.
|
Although the results have been contradictory, there is evidence to
suggest that CD40 can mediate a rise in intracellular calcium
concentrations in B cells (17). We therefore measured CD40-induced
changes in cytosolic calcium in human ASM. After the addition of CD40LT
to fura-2-loaded ASM cells, there was a gradual and protracted increase
in cytosolic calcium (Fig. 3A). The average increase in
cytosolic calcium evoked by CD40LT was 141 ± 15 nM
(n = 15–25 cells). This increase was abrogated by
pretreatment with blocking anti-CD40LT Abs (Fig. 3B).
Similar results were obtained when cells were stimulated with
anti-CD40 (Fig. 3C), in which the average increase in
cytosolic calcium evoked was 103 ± 17 nM (n = 33
cells). The calcium response to CD40LT or anti-CD40 stimulation
differed from that seen in response to smooth muscle cell contractile
agonists such as bradykinin, which was rapid, with a maximum peak
increase to 268 ± 38 nM (Fig. 3C). The specificity of
the response is evidenced by the lack of effect of an isotype-matched
binding anti-ICAM-1 control Ab (Fig. 3D). The addition
of NiCl2 before Ab cross-linking abolished the CD40-induced
signal (Fig. 4), suggesting that the
increase in intracellular calcium was dependent on an influx through
transmembrane calcium channels. Similar effects were seen using another
divalent cation MnCl2 (data not shown). This differs from
the response to bradykinin (Fig. 4), which was shown previously to be
due to release of intracellular calcium stores (39, 40). Finally,
pretreatment of the ASM with the tyrosine kinase inhibitors genistein
(Fig. 5) or herbimycin (data not shown)
completely inhibited the early CD40-induced calcium response,
suggesting that calcium mobilization induced by engagement of CD40 is
coupled to activation of PTK. Genistein had no effect, however, on the
bradykinin-evoked calcium response (Fig. 5).
|
|
|
We next attempted to identify some of the receptor-proximal
signaling events that are activated by CD40 cross-linking. It was
demonstrated previously that engagement of CD40 induced tyrosine
phosphorylation in transformed or activated, but not resting, B cells
(9, 41, 42). In addition, the effect of genistein on the calcium
response described above indicated that CD40 may be coupled to PTK
signal-transduction pathways in ASM. To directly assess whether CD40
mediated activation of PTK, cells were made quiescent by culturing in
serum-free media for 24 h, then stimulated with anti-CD40 mAb
for the indicated times. Protein tyrosine phosphorylation of cellular
proteins was detected by immunoblotting with anti-phosphotyrosine
Abs. Tyrosine-phosphorylated species with Mr of
40 to 50 kDa were detected at 10 to 15 min following stimulation (Fig. 6). Phosphorylation of these proteins was
not seen when smooth muscle cells were incubated with an
isotype-matched control Ab (data not shown). Similar to the
CD40-mediated increase in intracellular calcium, CD40-induced tyrosine
phosphorylation did not require pretreatment of the cells with
cytokine.
|
B activation in ASM
The transcription factor NF-B is important for maximal
transcription of many cellular products involved in inflammatory
responses, such as TNF-, IL-1ß, IL-6, and IL-8. To test whether
CD40 could induce activation of NF-B in ASM, cells were pretreated
with IFN- for 72 h, then stimulated with soluble CD40LT. Two
NF-B/DNA-binding complexes were observed (Fig. 7A). An inducible NF-B
activity was seen as early as 15 min following exposure to CD40LT,
which peaked at approximately 30 min, then decreased. In comparison,
TNF- induced a comigrating NF-B complex more rapidly, and the
presence of this complex was sustained over the same time course (data
not shown). A second complex was constitutively present and unaffected
by treatment with either CD40LT or TNF-. Formation of the inducible
complex was inhibited by excess cold oligonucleotide (Fig. 7B). Cells that were stimulated with CD40L, in the absence
of IFN- pretreatment, exhibited the constitutive, but not the
inducible NF-B complex (data not shown). To determine the subunit
composition of these complexes, nuclear extracts were incubated with
specific subunit Abs. Anti-p65/RelA abrogated formation of the
inducible complex, but had no effect on the constitutive complex (Fig. 7B). Anti-p50 had a partial inhibitory effect on formation
of the inducible NF-B complex (Fig. 7B). No supershift or
inhibition of either complex was seen with anti-c-Rel, suggesting
that these effects were specific. Thus, it appears that CD40 activates
the formation of an NF-B heterodimer, consisting of at least p50 and
p65/RelA. In addition, this effect was dependent on priming of the
cells by IFN-, which alone had no effect.
|
B
activation and IL-6 secretion
Engagement of the CD40 receptor results in mobilization of
extracellular calcium in ASM. We examined whether extracellular calcium
was necessary for the proinflammatory effects of CD40, including
activation of NF-B and IL-6. ASM cells were treated with IFN- for
72 h, then placed in serum-free media containing 2 mM calcium. The
cells were treated for 15 min with 4 mM NiCl2 before being
stimulated with CD40LT. Pretreatment with NiCl2 completely
abrogated the ability of CD40LT to activate the inducible NF-B
complex, but had no effect on the constitutive complex (Fig. 8A). NiCl2 alone
had no demonstrable effect on NF-B activation. In addition,
pretreatment with NiCl2 inhibited CD40-induced increases in
IL-6 secretion by ASM, but had minimal effects on basal secretion (Fig. 8B).
|
|
Discussion |
|---|
|
TopAbstractIntroductionMaterials and MethodsResultsDiscussionReferences |
|---|
, that do not by themselves induce ASM contraction, can
prime airway smooth muscle cells to respond at lower doses to directly
acting bronchoconstrictors (31, 32). A third, but much less
well-studied, mechanism involves contact-dependent cell-to-cell
interactions of ASM with activated inflammatory cells within the
airway. In support of this contact-dependent mechanism, we have
reported recently the up-regulation of the cell adhesion molecules
ICAM-1 and VCAM-1 on TNF--stimulated ASM cells (33). These, along
with CD44, support the adhesion of activated T cells to ASM (33).
Importantly, adhesion of these activated lymphocytes induces DNA
synthesis in ASM cells (33). In this study, we extended our prior
observations by demonstrating that an additional ligand pair
(CD40-CD40L) can impart cellular signals that modulate smooth muscle
cell function. We have delineated a potentially important
signal-transduction pathway in ASM, involving PTK-dependent activation
of calcium mobilization. This calcium response appears to be required
for the further downstream activation of NF-B and secretion of IL-6,
a gene known to be regulated by NF-B. These data provide further
evidence for the role of CD40 in regulating the inflammatory
response.
We initially tested the ability of CD40 engagement to affect ASM
cytokine secretion focusing on the pleiotropic inflammatory cytokine
IL-6. CD40LT induced a significant enhancement of IL-6 secretion by
both unstimulated and TNF-- and IFN--treated ASM. Similar
findings have been noted in both transformed (25) as well as primary
fibroblasts (24, 29), keratinocytes (27), and vascular smooth muscle
cells (28). IL-6 has a number of proinflammatory effects, including its
ability to stimulate T cell proliferation (43) and up-regulate
IL-4-dependent IgE production (44). In addition, IL-6 has been shown to
increase the phosphorylation of CD40 in B cells (45), supporting the
idea of a CD40/IL-6 feedback loop. Therefore, the ability of CD40 to
enhance IL-6 production by ASM has important implications for airway
inflammation.
We also studied the effect of CD40 engagement on intracellular calcium levels. This response has physiologic and pathophysiologic significance since intracellular calcium is an essential second messenger regulating smooth muscle cell contractility (reviewed in 46 . Previous data regarding CD40-induced calcium mobilization in B cells have been variable and have not been investigated in other cell types of which we are aware. Klaus et al. (17) directly measured intracellular calcium in murine B cells in response to anti-CD40 and observed a slow, moderate increase. In contrast, other investigators found no increase in intracellular calcium following engagement of CD40 on either human (47) or murine (48) B cells. This discrepancy may be due to both species-specific and activation state-dependent differences in CD40 signaling.
We found that engagement of CD40 on ASM consistently evoked an increase
in intracellular calcium. The calcium mobilization induced by CD40 was
slow and protracted, contrasting with the rapid and transient response
induced by agonists that release inositol-3-phosphate-dependent calcium
stores (49). These data suggest that CD40-mediated calcium mobilization
involves a pathway distinct from the classical phospholipase C
pathways, which are activated by agonists that bind to
seven-transmembrane-spanning G protein-coupled receptors (reviewed in
50 . The CD40-induced calcium mobilization we observed in ASM was
dependent on an influx of extracellular calcium, inasmuch as the use of
competitive inhibitors of calcium influx, such as NiCl2 or
MnCl2, abrogated the response. Furthermore, we found that
extracellular calcium was also required for the CD40-induced activation
of NF-B and IL-6 secretion in ASM cells. Others have shown that
NF-B is a calcium-sensitive transcriptional regulator. For example,
Kanno and Siebenlist (51) demonstrated that TCR-mediated activation of
NF-B was abrogated in the presence of a calcium channel blocker.
Similarly, studies from Dolmetsch et al. (52) demonstrated that both
the amplitude and duration of calcium signals could modulate gene
transcription. Large transient rises in intracellular calcium were
found to activate both NF-B and JNK in B lymphocytes.
The underlying mechanisms whereby CD40 activates calcium influx remain to be determined. Consistent with our data in ASM, Wijetunge et al. (53, 54) reported that voltage-operated calcium channels could be modulated by endogenous tyrosine kinases, including pp60c-src, based on the fact that the calcium channel currents were inhibited completely by tyrosine kinase inhibitors, including genistein. We observed no change in the tyrosine phosphorylation of src (unpublished observation). However, the CD40-induced calcium transient in ASM was abolished completely by genistein and herbimycin, while these inhibitors had no effect on agonist-induced calcium mobilization. Together, these results suggest that the CD40-mediated calcium response in ASM may involve the activation of voltage-operated calcium channels, which were shown to be functionally present in ASM cells (40, 55), and that this may be coupled to PTK pathways.
Data derived from transformed B cell lines or resting or activated
normal B cells suggest that engagement of CD40 leads to both PTK and
serine/threonine kinase activation (7, 8, 47, 48, 56). Little is known,
however, about CD40 coupling to PTK signaling pathways in non-B cells.
Gaspari et al. (27) described tyrosine phosphorylation of a single
50-kDa species in keratinocytes stimulated with anti-CD40 Abs. We
now demonostrate that in resting human ASM, CD40 cross-linking leads to
increases in protein tyrosine phosphorylation. This effect, as well as
the CD40-mediated increase in calcium mobilization, did not require
pretreatment of the smooth muscle cells with IFN-. On the other
hand, cytokine pretreatment enhanced CD40-mediated IL-6 secretion and
was required for CD40-mediated NF-B activation. This suggests that
cytokines may prime the smooth muscle cell for certain responses,
possibly through the modulation of transcription factors, as has been
described in macrophages (57, 58).
In summary, we have demonstrated for the first time that CD40 is
expressed functionally on the surface of human airway smooth muscle,
and delineated a CD40-mediated signal-transduction pathway involving
PTK-dependent calcium mobilization and calcium-dependent activation of
NF-B and IL-6 secretion. Interactions between CD40-positive ASM and
CD40L-positive cells such as CD4+ T lymphocytes or
eosinophils should thus be considered a potentially important component
of the inflammatory response of the airways. Future studies will focus
on defining the role of these molecules in in vivo models of airway
inflammation, in defining other physiologic important consequences of
CD40 engagement, and in understanding the molecular events that
regulate signaling by CD40.
|
Footnotes |
|---|
2 Address correspondence and reprint requests to Dr. Aili Lazaar, Pulmonary and Critical Care Division, Hospital of University of Pennsylvania, Maloney 872, 3600 Spruce Street, Philadelphia, PA 19104. E-mail address:
3 Abbreviations used in this paper: CD40L, CD40 ligand; ASM, airway smooth muscle; CD40LT, CD40 ligand trimer; PTK, protein tyrosine kinase.
Received for publication February 17, 1998. Accepted for publication May 19, 1998.
|
References |
|---|
|
TopAbstractIntroductionMaterials and MethodsResultsDiscussionReferences |
|---|
2. J. Exp. Med. 179:673.-p55 receptor induces myocyte proliferation and modulates agonist-evoked calcium transients in cultured human tracheal smooth muscle cells. Am. J. Respir. Cell Mol. Biol. 15:55.[Abstract]
of calcium signals induced by bradykinin and carbachol in human tracheal smooth muscle cells. Br. J. Pharmacol. 114:4.[Medline]
-Thrombin increases cytosolic calcium and induces human airway smooth muscle cell proliferation. Am. J. Respir. Cell Mol. Biol. 13:205.[Abstract]
B via T cell receptor requires a Raf kinase and Ca2+ influx. J. Immunol. 157:5277.[Abstract]
and tumor necrosis factor- in transcriptional activation is mediated by cooperation between signal transducer and activator of transcription 1 and nuclear factor B. J. Biol. Chem. 272:14899.B by tumor necrosis factor and interferon via enhanced I B degradation and de novo I Bß degradation. Mol. Cell. Biol. 17:6746.[Abstract]
This article has been cited by other articles:
|
|
 |
|
  S. Zuyderduyn, M. B. Sukkar, A. Fust, S. Dhaliwal, and J. K. Burgess Treating asthma means treating airway smooth muscle cells Eur. Respir. J., August 1, 2008; 32(2): 265 - 274. [Abstract] [Full Text] [PDF]
|
|
|
|
|
|
K. Kanai, K. Asano, T. Hisamitsu, and H. Suzaki Suppression of matrix metalloproteinase production from nasal fibroblasts by macrolide antibiotics in vitro Eur. Respir. J., May 1, 2004; 23(5): 671 - 678. [Abstract] [Full Text] [PDF]
|
|
|
|
 |
|
 O. Tliba, S. Tliba, C. Da Huang, R. K. Hoffman, P. DeLong, R. A. Panettieri Jr., and Y. Amrani Tumor Necrosis Factor {alpha} Modulates Airway Smooth Muscle Function via the Autocrine Action of Interferon {beta} J. Biol. Chem., December 12, 2003; 278(50): 50615 - 50623. [Abstract] [Full Text] [PDF]
|
|
|
|
 |
|
 C M Gelbmann, S N Leeb, D Vogl, M Maendel, H Herfarth, J Scholmerich, W Falk, and G Rogler Inducible CD40 expression mediates NF{kappa}B activation and cytokine secretion in human colonic fibroblasts Gut, October 1, 2003; 52(10): 1448 - 1456. [Abstract] [Full Text] [PDF]
|
|
|
|
 |
|
 Z. Zhao, Y. Qian, D. Wald, Y.-F. Xia, J.-G. Geng, and X. Li IFN Regulatory Factor-1 Is Required for the Up-Regulation of the CD40-NF-{kappa}B Activator 1 Axis During Airway Inflammation J. Immunol., June 1, 2003; 170(11): 5674 - 5680. [Abstract] [Full Text] [PDF]
|
|
|
|
|
|
S. M. Propst, K. Estell, and L. M. Schwiebert CD40-mediated Activation of NF-kappa B in Airway Epithelial Cells J. Biol. Chem., September 27, 2002; 277(40): 37054 - 37063. [Abstract] [Full Text] [PDF]
|
|
|
|
 |
|
 A. J. Ammit, A. L. Lazaar, C. Irani, G. M. O'Neill, N. D. Gordon, Y. Amrani, R. B. Penn, and R. A. Panettieri Jr. Tumor Necrosis Factor-alpha -Induced Secretion of RANTES and Interleukin-6 from Human Airway Smooth Muscle Cells . Modulation by Glucocorticoids and beta -Agonists Am. J. Respir. Cell Mol. Biol., April 1, 2002; 26(4): 465 - 474. [Abstract] [Full Text] [PDF]
|
|
|
|
 |
|
 U. Schonbeck and P. Libby CD40 Signaling and Plaque Instability Circ. Res., December 7, 2001; 89(12): 1092 - 1103. [Abstract] [Full Text] [PDF]
|
|
|
|
 |
|
 S. Page, A. J. Ammit, J. L. Black, and C. L. Armour Human mast cell and airway smooth muscle cell interactions: implications for asthma Am J Physiol Lung Cell Mol Physiol, December 1, 2001; 281(6): L1313 - L1323. [Abstract] [Full Text] [PDF]
|
|
|
|
 |
|
 J. L. BLACK, M. ROTH, J. LEE, S. CARLIN, and P. R. A. JOHNSON Mechanisms of Airway Remodeling . Airway Smooth Muscle Am. J. Respir. Crit. Care Med., November 15, 2001; 164(10): S63 - 66. [Abstract] [Full Text] [PDF]
|
|
|
|
|
|
A. L. Lazaar, V. P. Krymskaya, and S. K. P. Das VCAM-1 Activates Phosphatidylinositol 3-Kinase and Induces p120Cbl Phosphorylation in Human Airway Smooth Muscle Cells J. Immunol., January 1, 2001; 166(1): 155 - 161. [Abstract] [Full Text] [PDF]
|
|
|
|
|
|
A. J. Ammit, R. K. Hoffman, Y. Amrani, A. L. Lazaar, D. W. P. Hay, T. J. Torphy, R. B. Penn, and R. A. Panettieri Jr. Tumor Necrosis Factor-alpha -Induced Secretion of RANTES and Interleukin-6 from Human Airway Smooth-Muscle Cells . Modulation by Cyclic Adenosine Monophosphate Am. J. Respir. Cell Mol. Biol., December 1, 2000; 23(6): 794 - 802. [Abstract] [Full Text]
|
|
|
|
 |
|
 J. Tan, T. Town, T. Mori, Y. Wu, M. Saxe, F. Crawford, and M. Mullan CD45 Opposes beta -Amyloid Peptide-Induced Microglial Activation via Inhibition of p44/42 Mitogen-Activated Protein Kinase J. Neurosci., October 15, 2000; 20(20): 7587 - 7594. [Abstract] [Full Text] [PDF]
|
|
|
|
|
|
S. M. Propst, R. Denson, E. Rothstein, K. Estell, and L. M. Schwiebert Proinflammatory and Th2-Derived Cytokines Modulate CD40-Mediated Expression of Inflammatory Mediators in Airway Epithelia: Implications for the Role of Epithelial CD40 in Airway Inflammation J. Immunol., August 15, 2000; 165(4): 2214 - 2221. [Abstract] [Full Text] [PDF]
|
|
|
|
|
|
S. McKay, S. J. Hirst, M. B.-d. Haas, J. C. de Jongste, H. C. Hoogsteden, P. R. Saxena, and H. S. Sharma Tumor Necrosis Factor-alpha Enhances mRNA Expression and Secretion of Interleukin-6 in Cultured Human Airway Smooth Muscle Cells Am. J. Respir. Cell Mol. Biol., July 1, 2000; 23(1): 103 - 111. [Abstract] [Full Text]
|
|
|
|
 |
|
 Y. Amrani, A. L. Lazaar, R. Hoffman, K. Amin, S. Ousmer, and R. A. Panettieri Jr. Activation of p55 Tumor Necrosis Factor-alpha Receptor-1 Coupled to Tumor Necrosis Factor Receptor-Associated Factor 2 Stimulates Intercellular Adhesion Molecule-1 Expression by Modulating a Thapsigargin-Sensitive Pathway in Human Tracheal Smooth Muscle Cells Mol. Pharmacol., July 1, 2000; 58(1): 237 - 245. [Abstract] [Full Text]
|
|
|
|
|
|
Y. Amrani, A. L. Lazaar, and R. A. Panettieri Jr. Up-Regulation of ICAM-1 by Cytokines in Human Tracheal Smooth Muscle Cells Involves an NF-{kappa}B-Dependent Signaling Pathway That Is Only Partially Sensitive to Dexamethasone J. Immunol., August 15, 1999; 163(4): 2128 - 2134. [Abstract] [Full Text] [PDF]
|
|
|
|
|
|
G. W. Glazner, S. Camandola, J. D. Geiger, and M. P. Mattson Endoplasmic Reticulum D-myo-Inositol 1,4,5-Trisphosphate-sensitive Stores Regulate Nuclear Factor-kappa B Binding Activity in a Calcium-independent Manner J. Biol. Chem., June 15, 2001; 276(25): 22461 - 22467. [Abstract] [Full Text] [PDF]
|
|
| |||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||
| HOME | HELP | FEEDBACK | SUBSCRIPTIONS | ARCHIVE | SEARCH | TABLE OF CONTENTS |
