| HOME | HELP | FEEDBACK | SUBSCRIPTIONS | ARCHIVE | SEARCH | TABLE OF CONTENTS |
|
|
|
|||||||
|
|||||||||
B and TNF-
: A Positive Autocrine Loop in Human Lung Mast Cells?
Division of Infection, Inflammation and Repair, School of Medicine, Southampton General Hospital, Southampton, United Kingdom
 |
Abstract |
|---|
 Top Abstract IntroductionMaterials and MethodsResultsDiscussionReferences |
|---|
, by mast cells is
crucial for the initiation of the allergic response. A key
transcription factor involved in the synthesis of TNF- is NF-
B.
Using a mAb specific for the activated form of NF-B,
immunocytochemistry, confocal microscopy, and gel shift assays have
been used in conjunction to localize this transcription factor to human
lung mast cells and to study its activation. Activation of mast cells
with stem cell factor (10 ng/ml) and anti-IgE (1 µg/ml)
induced maximal activation of NF-B at 4 and 2 h, respectively.
In contrast, with TNF- (5 ng/ml) maximal activation occurred within
15 min. Parallel falls in IB were demonstrated. Confocal microscopy
demonstrated the localization of the activated form of NF-B to the
nuclei of activated mast cells. NF-B activation was verified using a
gel shift assay. A supershift assay showed mast cell NF-B to be
composed primarily of p50 with smaller amounts of p65. No interaction
with Abs for Rel-A, c-Rel, Rel-B, and p52 was seen. Immunocytochemistry
and ELISAs showed TNF- to be stored within mast cells and released
into the extracellular environment following activation. The possible
participation of TNF- generated by mast cells in NF-B activation
by anti-IgE was investigated using a blocking Ab for TNF-. The
blocking Ab reduced NF-B activation by anti-IgE by >50%,
suggesting that the release of preformed mast cell-associated TNF-
acts as a positive autocrine feedback signal to augment NF-B
activation and production of further cytokine, including GM-CSF and
IL-8. |
Introduction |
|---|
|
TopAbstractIntroductionMaterials and MethodsResultsDiscussionReferences |
|---|
, a pleotropic cytokine encoded on chromosome 6, which exists in
its biologically active form as a homotrimer of a 17-kDa subunit
cleaved proteolytically from its 26-kDa cell surface-associated form
(2, 3). It has a broad range of biological activities
associated with inflammatory diseases, many of which are pertinent to
allergy (reviewed in Ref. 4). Preformed immunoreactive
TNF- has been observed within the granules of mast cells from human
skin (5) and lung (6), suggesting its rapid
availability following mast cell activation. That this preformed
TNF- may be biologically relevant has been shown by its release
within 2 min of allergen challenge in parallel with tryptase in
patients with allergic rhinitis (7).
A key transcription factor involved in the synthesis of TNF- is
NF-B. NF-B, which also regulates the transcription of a number of
proinflammatory molecules, including GM-CSF, IL-8, IL-2, IL-6,
E-selectin, ICAM-1, and VCAM-1, may be of variable composition but is
classically presented in a wide range of cells as a heterodimer
comprising of p50 and p65, each of which contains the 300-aa
NF-B/rel/dorsal domain (8, 9). In resting cells NF-B
is present in the cytoplasm in an inactive form reversibly bound to
proteins of the IB family (10). On cell
stimulation by a range of stimuli including TNF-, IL-1, IL-2,
leukotriene B4, viruses, and free radicals
(10), IB undergoes proteolysis and the nuclear location
site of NF-B becomes revealed. This activation of NF-B is
necessary for its translocation across the nuclear membrane and binding
to its target gene promoter regions. In addition to increasing the
transcription of cytokines and adhesion proteins, NF-B also
increases the transcription of IB, thus leading to its own
inactivation and subsequent termination of the response.
In human lung mast cells, we demonstrate the presence and activation of
NF-B and the generation of TNF-. We then examined the hypothesis
that when mast cells are stimulated immunologically, the release of
preformed TNF- acts as a positive autocrine feedback signal to
augment NF-B activation.
|
Materials and Methods |
|---|
|
TopAbstractIntroductionMaterials and MethodsResultsDiscussionReferences |
|---|
Human lung cells were dispersed from macroscopically normal
human lung by an enzymatic procedure described previously
(11). Mast cell numbers were counted in a Neubauer
hemocytometer after metachromatic staining with Kimura stain
(12). Cell dispersates initially contained 0.4 ±
0.1 x 106 mast cells/g lung tissue in a
purity of 
5%. Erythrocytes were removed by centrifugation through a
65% continuous Percoll gradient (1.084 g/ml) and T lymphocytes by
serial affinity selection using anti-CD2-coated magnetic beads
(Dynabeads M-450 Pan-T; Dynal Biotech, Oslo, Norway), a technique which
removes >99% of T lymphocytes. Nucleated cells were then incubated
with the anti-c-kit mAb YB5.B8 (13, 14)
(donated by Dr. L. K. Ashman, Institute of Medical and Veterinary
Science, Adelaide, South Australia), washed, and subjected to
positive magnetic affinity using goat anti-mouse IgG-coated
Dynabeads (15). This procedure yielded mast cells,
identified by the mAb AA1 against tryptase (16), in
purities of >95%. Following purification, to allow the cells to
recover the rigors of purification and to sensitize them, mast cells
were incubated for 16 h with human myeloma IgE (3 µg/ml;
Calbiochem-Novabiochem, San Diego, CA). Following sensitization mast
cells were cultured at 1 x 105 cells/well
in a 96-well tissue culture plate in humidified 95% air with 5%
CO2 at 37°C in DMEM supplemented with 2 mM
L-glutamine, 200 U penicillin/200 µg/ml
streptomycin, and 1% FCS.
Activation of NF-B with immunological mediators
To investigate the kinetic activation of NF-B, degradation of
IB and the immunoreactivity for TNF-, 1 x
105 human lung mast cells following purification
and passive sensitization were incubated in medium alone and compared
with mast cells activated with recombinant human stem cell factor
(SCF5; 10/50 ng/ml,
donated by Cytomed, Cambridge, MA) in the presence or absence of either
anti-IgE (1 µg/ml; Serotec, Oxford, U.K.) or TNF- (5 ng/ml)
for various time intervals (0.25, 0.5, 1, 2, 4, 6, 8, 12, 24, and
48 h) up to 48 h. Following experimentation, the cells were
spun in a cytocentrifuge (20 x g) for 7 min onto
poly-L-lysine-coated glass slides and stained
with specific mAbs: for activated
NF-Ba, 2C7 (17) (Pharmacia
Upjohn, Kalamazoo, MI), IB (Santa Cruz Biotechnology, Santa Cruz,
CA) or TNF- (18) (Celltech, Slough, U.K.), GM-CSF
(Genzyme, Cambridge, U.K.), and IL-8 (Dr. I. Lindley, Novartis, Vienna,
Austria). Slides were developed using an indirect peroxidase detection
system with the substrate 3-amino-9-ethylcarbazole. Two hundred to 300
cells were counted, depending upon the quality of the cytospin, and the
percentage of positive cells was calculated.
Colocalization of activated NF-B to the nuclei of human lung
mast cells
Two-channel confocal microscopy was used to produce a combined
image of cytospin preparations in which activated NF-B was stained
with mAb 2C7 using a biotin and fluorescein detection system
(2C7-biotin-FITC), and the cell nuclei were counterstained with
propidium iodide. Colocalization analysis was performed and a
multicolor look-up table was used to show the extent of colocalization
of activated NF-B and the nucleus.
EMSA
Nuclear proteins were isolated from human purified lung mast
cells and incubated with a radiolabeled NF-B consensus DNA sequence.
The reaction mixture was then subjected to gel electrophoresis using a
nondenaturing polyacrylamide gel. The gel was then subjected to
autoradiography and the heavier DNA-NF-B complexes were identified
by their slower electrophoretic migration. Supershift assays were
performed by preincubating the nuclear extracts with Abs to subunits,
Rel-A, Rel-B, c-Rel, p50, p52, and p65 of NF-B (Santa Cruz
Biotechnology).
Statistical analyses
Data, expressed as the mean ± SEM, were tested for
normality using the Shapiro-Wilk test. In normally distributed data,
the difference between two means was tested for significance using
Student’s t test for paired data. In skewed nonparametric
data, the difference between two means was tested for significance
using the Mann-Whitney U test. The difference between two
means was said to be significant when p < 0.05 and
greatly significant when p < 0.001. To determine
whether or not the immunoreactivity of NF-Ba
correlated with the immunoreactivity for TNF-, Pearson’s
correlation was used.
|
Results |
|---|
|
TopAbstractIntroductionMaterials and MethodsResultsDiscussionReferences |
|---|
B
To determine the optimal concentrations of SCF, anti-IgE and
TNF- required to activate NF-B to its active form
(NF-Ba), five preliminary experiments were
performed in which mast cells were incubated with the stimulants for
4 h and the percentage of cells staining positive for
immunoreactive NF-Ba was determined. SCF
(1–100 ng/ml) caused a concentration-related increase in
NF-Ba+ mast cells from a
baseline of 10 ± 5% (medium control) to a maximum of 52 ±
12% (p < 0.005) at 100 ng/ml. A concentration
of 10 ng/ml SCF, which induced NF-B activation in 26 ± 4%
cells (p < 0.02), was used in additional
experiments. Anti-IgE (0.1–10 µg/ml) also induced a
concentration-related increase in the number of
NF-Ba+ mast cells from
10 ± 5% to a maximum of 44 ± 6%
(p < 0.001) at 5 µg/ml. A concentration of 1
µg/ml anti-IgE, which caused 35 ± 6%
(p < 0.005) activation, was used in additional
experiments. TNF- (0.01–50 ng/ml) again caused a
concentration-related increase in the number of
NF-Ba+ mast cells from
15 ± 5% to a maximum of 70 ± 4%
(p < 0.001) at 50 ng/ml. A concentration
of 5 ng/ml TNF-, which caused 59 ± 2%
(p < 0.001) activation, was used in additional
experiments.
Kinetics of NF-B activation
Fig. 1
a shows that when
mast cells were incubated with 10 ng/ml SCF for up to 48 h, a
maximum percentage of NF-Ba+
mast cells of 34 ± 9% (p < 0.05,
n = 5) was seen at 4 h, after which numbers waned.
In the same experiments, 1 µg/ml anti-IgE in the presence of 10
ng/ml SCF significantly (p < 0.05) enhanced
NF-B activation at 30 min, 1 h, and 2 h, a maximum of
38 ± 5% being observed at 2 h.
|
induced a more rapid activation of NF-B (Fig. 1
b), 19 ± 1% of mast cells expressing
NF-Ba within 1 min and rising to a maximum of
63 ± 2% at 15 min (both p < 0.001,
n = 5). In the presence of SCF, this was significantly
(p < 0.001) enhanced to 77 ± 2% at 15
min. NF-B activation remained significantly
(p < 0.05) elevated throughout the 48-h
observation period.
IB immunoreactivity
The activation of NF-B within mast cells should be accompanied
by a fall in its inhibitory protein, IB. This was demonstrated in
five experiments in which the percentage of mast cells showing
immunoreactivity for IB at baseline was 46 ± 2%. Incubation
of these cells with 10 ng/ml SCF, 1 µg/ml anti-IgE, and 5 ng/ml
TNF- (the last two both in the presence of 10 ng/ml SCF) all caused
an inhibition of IB immunoreactivity which paralleled the kinetics
of the increase in NF-B immunoreactivity (Fig. 2).
|
To verify NF-B activation, a gel shift assay was used in which
the electrophoretic migration of the heavier DNA-NF-B complexes is
slower than inactive NF-B (Fig. 3).
Incubation of mast cells for 4 h in medium alone contained very
little activated NF-B bound to the radiolabeled NF-B-binding
motif. Activation with 1 µg/ml anti-IgE for 4 h and 5
ng/ml TNF- for 15 min induced the activation of NF-B, the latter
appearing to be more dense on the gel. Preincubation of mast cells for
1 h with 10 µM of the NF-B inhibitor, calpain inhibitor 1,
prevented activation of NF-B by TNF-.
|
To gain further insight into the composition of activated NF-B,
a gel supershift assay was used. Nuclear protein purified from mast
cells that had been activated with 5 ng/ml TNF- for 15 min was
incubated with mAbs for Rel-A, Rel-B, c-Rel, p50, p52, and p65. Fig. 4 shows the presence of large amounts of
p50 and smaller amounts of p65. No interaction with the other Abs
was seen.
|
B to the nucleus
To visualize NF-Ba within the nucleus,
mast cells were incubated for 4 h in medium alone or activated
with anti-IgE (1 µg/ml). Two-channel confocal microscopy was used
to produce a combined image of cytospin preparations stained with
2C7-biotin-FITC in conjunction with the nuclear stain propidium iodide
(Fig. 5). Colocalization analysis using
multicolor look-up tables demonstrated enhanced levels of
NF-Ba, clearly enhanced within the nuclei of
mast cells activated with anti-IgE compared with controls.
|
and other cytokines
Because the measurement of cytokines by ELISA requires large
numbers of cells, initial studies on TNF- production were performed
by counting in cytospin preparations the number of mast cells that
stained positively for NF-Ba and TNF-.
These studies confirmed the presence at 4 h and 15 min,
respectively, of NF-Ba when mast cells were
activated with 1 µg/ml anti-IgE and 5 ng/ml TNF-, both in the
presence of 10 ng/ml SCF. These stimuli also led to a time-related
increase in TNF--positive cells up to 12 h (Fig. 6a). Preincubation of the
cells with 10 µM calpain inhibitor 1 for 1 h before stimulation
significantly reduced the number of cells staining for both
NF-Ba and TNF-. Other inhibitors of
NF-B activation, pentoxifylline (0.5 mM), pyrrolidine
dithiocarbamate (10 µM), and gliotoxin (1 pg/ml), reduced
TNF--stimulated NF-B activation 89, 91, and 63%, respectively
(all P < 0.001).
|
alone
significantly increased the number of mast cells staining positive for
NF-Ba, TNF-, GM-CSF, and IL-8. Again, the
degree of activation was significantly (p <
0.05) reduced by calpain (Fig. 6b).
The production of TNF- by mast cells was confirmed in six
experiments where mast cells were stimulated with 1 µg/ml
anti-IgE and 10 ng/ml SCF for 6, 12, or 24 h, and the
supernatant and cell lysate were assayed for TNF- using ELISA.
Baseline TNF- levels were close to the level of detection, being
0.37 ± 0.06 and 1.06 ± 0.2 pg/1 x
106 mast cells for supernatant and lysate. In
unstimulated cells, these levels did not change significantly at any
point throughout the 24-h incubation period. Following stimulation, the
concentration of TNF- in the supernatant rose to a maximum of
6.56 ± 0.26 pg/1 x 106 mast cells
(p < 0.001) at the first observation point at
6 h and remained significantly elevated thereafter. Only small
amounts of TNF- were found in the lysate, but the concentration of
1.46 ± 0.20 pg/1 x 106 mast cells
found at 12 h was significantly (p <
0.005) above that of control.
In an additional 35 experiments, mast cells were stimulated for
24 h with 1 µg/ml anti-IgE in the presence of 50 ng/ml SCF.
The TNF- levels in the supernatant and pellet were 50.4 ± 7.7
and 16.3 ± 1.8 pg/1 x 106 mast cells
(both p < 0.001 compared with unstimulated control).
Fig. 7 shows that the TNF- levels
within the pellets were correlated significantly
(p < 0.005) with the concentrations in the
supernatant, the amount stored being 30% of that secreted.
|
contribute to NF-B activation?
To confirm the blocking activity of the anti-TNF- Ab, mast
cells were incubated for 1 h with 1–100 ng/ml of the Ab before
stimulation with 5 ng/ml TNF- for 15 min in five experiments. The
results show a concentration-related inhibition of the percentage of
cells staining for activated NF-B (Fig. 8). A concentration of 100 ng/ml blocking
Ab was used in additional experiments.
|
generated by mast cells in
NF-B activation by anti-IgE in the presence of SCF was
investigated in five experiments using a blocking Ab for TNF-. The
results (Fig. 9) show that the percentage
of cells containing NF-Ba following incubation
in medium alone for 4 h was 9 ± 1%. Activation of these
cells with 1 µg/ml anti-IgE in the presence of 10 ng/ml SCF
increased the percentage of immunoreactive cells to 38 ± 6%.
Preincubation of the cells for 1 h with 100 ng/ml of the blocking
mAb significantly reduced the percentage of immunoreactive cells to
18 ± 1% (p < 0.05).
|
|
Discussion |
|---|
|
TopAbstractIntroductionMaterials and MethodsResultsDiscussionReferences |
|---|
B,
immunocytochemistry, confocal microscopy, and gel shift assays have
been used in conjunction to localize this transcription factor to human
lung mast cells and to study its activation. The kinetics of NF-B
activation and its involvement in the production of TNF- have been
investigated following activation of purified mast cells with
anti-IgE, SCF, and TNF- itself. To explore the relationship
between NF-B activation and TNF- production, a range of NF-B
inhibitors has been used.
Activation of mast cells with SCF, anti-IgE, and TNF- induced
the activation of NF-B in a concentration-dependent manner with a
corresponding decline in IB immunoreactivity. Activation of mast
cells with SCF and anti-IgE induced maximal activation of NF-B
at 4 and 2 h, respectively. In contrast, TNF- induced a much
more rapid activation of NF-B, maximal activation occurring within
15 min. That this response was initiated by a TNF-
receptor-dependent mechanism was demonstrated by its inhibition by a
blocking mAb for TNF-. That this immunoreactivity was associated
with the activation of authentic NF-B was confirmed in gel shift
assays. Furthermore, supershift assays showed p50 to be the major
NF-B subunit in human lung mast cells, with smaller amounts of p65
also being present.
SCF is a key factor influencing the survival, maturation, migration,
and function of mast cells (15, 19, 20). In this study,
SCF was shown to both initiate NF-B activation and enhance
activation induced by TNF- and anti-IgE. The c-kit
receptor has intrinsic tyrosine kinase activity (21) and
upon agonist binding undergoes autophosphorylation (22).
Even though Fc
RI lacks intrinsic tyrosine kinase activity
(23) and relies upon closely associated tyrosine kinases
(24), the activation of mast cells via SCF or anti-IgE
leads to a virtually indistinguishable calcium signaling pattern
(25). This has been shown in previous studies to lead to a
similar pattern of early response genes including
c-fos, c-jun, and c-jun
, and
similar patterns of phosphorylation and activation of mitogen-activated
protein kinase (26). SCF has been demonstrated to both
induce the secretion of mast cell mediators directly (27)
and to regulate the extent of mediator release in mast cells activated
by anti-IgE-dependent mechanisms (15, 28). In
particular, anti-IgE and SCF stimulate the transcription and
secretion of TNF- when used independently and enhance the effects of
each other when used together. This was confirmed in the current study
in which the activation of mast cells with SCF alone or in combination
with anti-IgE led to NF-B activation and the production of
TNF-.
TNF- induces a variety of cellular responses via binding to its two
receptors (29). The ability of these receptors to
transduce signals is dependent upon the recruitment of TNFR-associated
factors (30) which initiate a number of downstream events,
including the activation of NF-B-inducing kinases (31, 32). TNF- has been reported to induce histamine release from
human skin mast cells (33, 34) and to enhance
IgE-dependent histamine release from sensitized lung mast cells
(35). Furthermore, the sustained release of preformed and
newly synthesized TNF- following appropriate stimulation represents
a mechanism by which mast cell-derived TNF- can exert its actions on
leukocyte migration and activation and the initiation of late-phase
allergic inflammation. With the use of KO mice and adoptive transfer
experiments, mast cell-derived TNF- has been shown to contribute
significantly to leukocyte infiltration (36). Also, unlike
macrophages and lymphocytes, which contain little or no preformed
TNF-, this cytokine is stored in human mast cells in many tissue
sites (5, 6, 37). But is this TNF- available for rapid
release following mast cell activation? Two clinical studies suggest
that it is, TNF- having been detected within 2 min in the nasal
lavage fluid following allergen challenge in hay fever (7)
and in the venous blood following challenge of the skin in cold
urticaria (38). However, it was not possible to confirm
this directly by ELISA measurement of TNF- in our in vitro studies
because the levels of "total cell-associated" cytokine were close
to the levels of detection. However, we did obtain indirect evidence of
TNF- release by use of a blocking Ab that reduced NF-B activation
by anti-IgE and SCF by >50%. Beside providing evidence for
TNF- release by human mast cells, this observation is highly
suggestive of a local autocrine feedback of TNF-, possibly even
membrane-associated TNF-, onto surface receptors on the cell from
which it is released. This would be consistent with the high affinity
of TNF- for its receptors (39).
This work has demonstrated important roles for TNF- and NF-B in
the activation of human mast cells. The observations that mast cells
both release and respond to TNF- indicates that there is a positive
autocrine loop which leads to augmentation of mast cell activation. Our
previous studies have shown that activation of bronchial explants and
nasal polyps stimulated ex vivo, with recombinant TNF-, lead to the
activation of NF-B in complex tissue systems in parallel with the
up-regulation of proinflammatory cytokines and inflammatory markers
(17). It is, therefore, suggested that the secretion of
TNF- from mast cells augments NF-B activation not only of mast
cells but also of surrounding inflammatory cells and thus has a
considerable proinflammatory effect on its local microenvironment.
|
Footnotes |
|---|
2 Current address: Laboratory for Allergy Transcriptome, The Institute of Physical and Chemical Research Center for Allergy and Immunology, National Research Institute for Child Health and Development, 3-35-31 Taishido, Setagaya-ku, Tokyo 154-8567, Japan.
3 Current address: Department of Pulmonary Medicine and Clinical Immunology, Dokkyo University School of Medicine, 880 Kitakobayashi, Mibu, Tochigi 321-0293, Japan.
4 Address correspondence and reprint requests to Dr. Martin K. Church, Dermato-pharmacology Unit, South Block 825, Southampton General Hospital, Southampton SO16 6YD, U.K. E-mail address: mkc{at}soton.ac.uk
5 Abbreviation used in this paper: SCF, stem cell factor.
Received for publication December 19, 2001. Accepted for publication August 9, 2001.
|
References |
|---|
|
TopAbstractIntroductionMaterials and MethodsResultsDiscussionReferences |
|---|
genes: structure, homology and chromosomal localisation. Nucleic Acids Res. 13:6361.: a potential mediator of asthma. Clin. Exp. Allergy 25:1038.[Medline]
, which induces endothelial leukocyte adhesion molecule 1. Proc. Natl. Acad. Sci. USA 88:4220. in normal and asthmatic airways: evidence for the human mast cell as a source of these cytokines. Am. J. Respir. Cell Mol. Biol. 10:471.[Abstract]
is localized to nasal mucosal mast-cells and is released in acute allergic rhinitis. Clin. Exp. Allergy 25:406.[Medline]
B. Immunol. Today 19:80.[Medline]
B and IB proteins: new discoveries and insights. Annu. Rev. Immunol. 14:649.[Medline]
B and expression of associated cytokines and adhesion molecules in human models of allergic inflammation. J. Pathol. 189:265.[Medline]
(TNF ) to blood vessels and macrophages in inflamed synovial tissue. Rheumatol. Int. 11:19.[Medline]
B activation. Cell 81:495.[Medline]
B kinase. Cell 90:373.[Medline]
B degradation and nuclear factor-B DNA binding are insufficient for interleukin-1 and tumor necrosis factor--induced B-dependent transcription: requirement for an additional activation pathway. J. Biol. Chem. 273:6607. (TNF-) activates human adenoidal and cutaneous mast cells to histamine secretion. Immunol. Lett. 59:139.[Medline]
on mediator release from human lung. Pulm. Pharmacol. 8:31.[Medline]
. J. Clin. Invest. 87:446.
release during systemic reaction in cold urticaria. J. Allergy Clin. Immunol. 93:501.[Medline]
This article has been cited by other articles:
|
|
 |
|
  P. N. Pushparaj, H. K. Tay, S. C. H'ng, N. Pitman, D. Xu, A. McKenzie, F. Y. Liew, and A. J. Melendez The cytokine interleukin-33 mediates anaphylactic shock PNAS, June 16, 2009; 106(24): 9773 - 9778. [Abstract] [Full Text] [PDF]
|
|
|
|
 |
|
 E. Ulleras, M. Karlberg, C. Moller Westerberg, J. Alfredsson, S. Gerondakis, A. Strasser, and G. Nilsson NFAT but not NF-{kappa}B is critical for transcriptional induction of the prosurvival gene A1 after IgE receptor activation in mast cells Blood, March 15, 2008; 111(6): 3081 - 3089. [Abstract] [Full Text] [PDF]
|
|
|
|
 |
|
 S. A. Parsons and P. A. Greer The Fps/Fes kinase regulates the inflammatory response to endotoxin through down-regulation of TLR4, NF-{kappa}B activation, and TNF-{alpha} secretion in macrophages J. Leukoc. Biol., December 1, 2006; 80(6): 1522 - 1528. [Abstract] [Full Text] [PDF]
|
|
|
|
 |
|
 H. V. Wright, D. Bailey, M. Kashyap, C. L. Kepley, M. S. Drutskaya, S. A. Nedospasov, and J. J. Ryan IL-3-Mediated TNF Production Is Necessary for Mast Cell Development J. Immunol., February 15, 2006; 176(4): 2114 - 2121. [Abstract] [Full Text] [PDF]
|
|
|
|
|
|
W. Zhao, C. A. Oskeritzian, A. L. Pozez, and L. B. Schwartz Cytokine Production by Skin-Derived Mast Cells: Endogenous Proteases Are Responsible for Degradation of Cytokines J. Immunol., August 15, 2005; 175(4): 2635 - 2642. [Abstract] [Full Text] [PDF]
|
|
|
|
|
|
Y. Peng, M. R. Power, B. Li, and T.-J. Lin Inhibition of IKK down-regulates antigen + IgE-induced TNF production by mast cells: a role for the IKK-I{kappa}B-NF-{kappa}B pathway in IgE-dependent mast cell activation J. Leukoc. Biol., June 1, 2005; 77(6): 975 - 983. [Abstract] [Full Text] [PDF]
|
|
|
|
|
|
A. Tanaka, M. Konno, S. Muto, N. Kambe, E. Morii, T. Nakahata, A. Itai, and H. Matsuda A novel NF-{kappa}B inhibitor, IMD-0354, suppresses neoplastic proliferation of human mast cells with constitutively activated c-kit receptors Blood, March 15, 2005; 105(6): 2324 - 2331. [Abstract] [Full Text] [PDF]
|
|
|
|
|
|
B. J. Davis, B. F. Flanagan, A. M. Gilfillan, D. D. Metcalfe, and J. W. Coleman Nitric Oxide Inhibits IgE-Dependent Cytokine Production and Fos and Jun Activation in Mast Cells J. Immunol., December 1, 2004; 173(11): 6914 - 6920. [Abstract] [Full Text] [PDF]
|
|
|
|
|
|
T. R. Hundley, A. M. Gilfillan, C. Tkaczyk, M. V. Andrade, D. D. Metcalfe, and M. A. Beaven Kit and Fc{epsilon}RI mediate unique and convergent signals for release of inflammatory mediators from human mast cells Blood, October 15, 2004; 104(8): 2410 - 2417. [Abstract] [Full Text] [PDF]
|
|
|
|
 |
|
 P. S. Jolly, M. Bektas, A. Olivera, C. Gonzalez-Espinosa, R. L. Proia, J. Rivera, S. Milstien, and S. Spiegel Transactivation of Sphingosine-1-Phosphate Receptors by Fc{varepsilon}RI Triggering Is Required for Normal Mast Cell Degranulation and Chemotaxis J. Exp. Med., April 5, 2004; 199(7): 959 - 970. [Abstract] [Full Text] [PDF]
|
|
|
|
 |
|
 Y.-Z. Wu, S. Medjane, S. Chabot, F. S. Kubrusly, I. Raw, M. Chignard, and L. Touqui Surfactant Protein-A and Phosphatidylglycerol Suppress Type IIA Phospholipase A2 Synthesis via Nuclear Factor-{kappa}B Am. J. Respir. Crit. Care Med., September 15, 2003; 168(6): 692 - 699. [Abstract] [Full Text] [PDF]
|
|
|
|
|
|
V. Lam, J. Kalesnikoff, C. W. K. Lee, V. Hernandez-Hansen, B. S. Wilson, J. M. Oliver, and G. Krystal IgE alone stimulates mast cell adhesion to fibronectin via pathways similar to those used by IgE + antigen but distinct from those used by Steel factor Blood, August 15, 2003; 102(4): 1405 - 1413. [Abstract] [Full Text] [PDF]
|
|
| ||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||
| HOME | HELP | FEEDBACK | SUBSCRIPTIONS | ARCHIVE | SEARCH | TABLE OF CONTENTS |
), 10 ng/ml
SCF alone (
), or tissue culture medium (
, unstimulated control).
At the end of the incubation, cytospin preparations were made and
stained immunocytochemically for NF-
) or tissue culture medium (
). Cells incubated in tissue culture medium for 6 h served as
unstimulated controls. At the end of the incubation, cytospin
preparations were made and stained immunocytochemically for
NF-
) and IL-8 (
) were also counted. In this study,
inhibition by calpain inhibitor 1 was statistically significant
(p < 0.05) for all cytokines. All results are the
mean ± SEM for five experiments.
