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*
Department of Pediatrics and Clinical Immunology, Mie University School of Medicine, Tsu, Mie, Japan; and
Department of Pediatrics, National Mie Chuo Hospital, Tsu, Mie, Japan
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Abstract |
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 Top Abstract IntroductionMaterials and MethodsResultsDiscussionReferences |
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-producing cells, whereas
the percentage of IL-2-producing T cells was decreased. These results
demonstrate that Rho GTPase in DC controls both characteristic shape
and immunogenic capacity. |
Introduction |
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TopAbstractIntroductionMaterials and MethodsResultsDiscussionReferences |
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To investigate the relationship between morphology and its function of
DC, we tried to modulate Rho family GTPases (Rho, Rac, and Cdc42), the
key regulator of cell shape, motility, and adhesion by actin
cytoskeletal reorganization (4). The best-characterized
Rho family protein is Rho, mainly because it can be specifically ADP
ribosylated and inactivated by exoenzyme C3 from Clostridium
botulinum. By using this inhibitor, it has been demonstrated in
several types of leukocyte that Rho is very important to display their
function (5, 6, 7, 8). Rho is required for stress fiber
formation, focal adhesion, and cell contractility, and Rho-induced
focal adhesion is distinct from Rac- and Cdc42-mediated small focal
complex (4). To the best of our knowledge, there has been
no report describing the role of Rho in the regulation of DC. In the
present study, we investigated the possible role of Rho in the unique
morphology of DC and its functional significance, by using exoenzyme C3
from C. botulinum as a specific inhibitor of Rho and a
specific Rho-associated coiled coil-containing kinase (p160ROCK)
inhibitor Y-27632. Our results demonstrate that C3 can enter into the
intact DC and inactivate Rho. C3 and Y-27632 markedly reduced actin
polymerization in parallel with disappearance of dendrites. C3-treated
DC exhibited 
80% reduction of T cell-stimulating capacity in
allogeneic MLR, despite increased IL-12 production probably because
initial interaction with T cell was disturbed.
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Materials and Methods |
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TopAbstractIntroductionMaterials and MethodsResultsDiscussionReferences |
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Culture medium was TCM-10 (RPMI 1640 supplemented with 10% FBS,
5 x 10-5 M 2-ME, 10 mM HEPES). The
following human recombinant cytokines were used: 50 ng/ml GM-CSF
(kindly provided by Kirin Brewery, Gunma, Japan), 10 ng/ml IL-4
(PeproTech, Rocky Hill, NJ), and 100 U/ml TNF-
(Genzyme, Cambridge,
MA). Recombinant exoenzyme C3 was kindly provided by S. Narumiya (Kyoto
University, Kyoto, Japan) (9). Y-27632, a specific
inhibitor of a Rho-associated protein kinase p160ROCK
(10), was supplied by Welfide (Saitama, Japan). PMA and
cytochalasin D were purchased from Sigma (St. Louis, MO).
Cell separation, culture, and staining
Peripheral blood was obtained from healthy adult volunteers, and
human cord blood was obtained with informed consent. Monocytes (Mo)
were negatively selected by using StemSep system (Stem Cell
Technologies, Vancouver, Canada), according to the
manufacturer’s instruction. Cells were tested for viability (>99%)
by trypan blue dye exclusion, and for purity (>90%
CD14+ Mo) by flow cytometry. Purified Mo were
cultured with 50 ng/ml GM-CSF and 10 ng/ml IL-4 for 4–7 days to obtain
immature DC (im-DC), then replenished with the same medium described
above plus TNF- (100 U/ml) or LPS to induce mature DC (m-DC)
(11). DCs were stained with May-Giemsa staining solution.
Dendrites, filopodial extensions, and large membrane expansions were
counted using a light microscope (Olympus, Tokyo, Japan). At least 200
cells were counted in each treatment. CD4+ T
cells were positively selected with CD4 mAb-coated M-450 Dynabeads
(Dynal, Oslo, Norway) or StemSep for CD4 negative selection, according
to the manufacturer’s instructions.
In vitro ADP-ribosylation assay
Mature DCs were washed once with PBS and centrifuged. Cells were resuspended and homogenized in lysis buffer containing 50 mM HEPES, pH 7.5, 0.25 M sucrose, 20 mM Tris-HCl, 5 mM MgCl2, 4 mM EDTA, 1 mM DTT, 2 mM benzamidine hydrochloride (Tokyo Kasei Kogyo, Tokyo, Japan), and 0.2 mM PMSF (12). The homogenates were centrifuged at 1000 x g for 5 min. Supernatants were incubated with reaction buffer (100 mM Tris-HCl, pH 8, 20 mM nicotinamide, 10 mM thymidine, 10 mM DTT, 5 mM MgCl2, 1 µCi [32P]NAD, with or without 100 ng of C3) at 30°C for 1 h. After the reaction, the mixture was subjected to SDS-PAGE, dried, and analyzed by autoradiography, as described (7). Autoradiographs were processed by Fuji BAS-2000 image analyzer (Fuji Film, Tokyo, Japan). [32P]NAD was purchased from Amersham Life Science (Little Chalfont, U.K.).
MLR
The allogeneic MLR assay was performed as described previously (13). For time- and dose-dependency experiments, DCs were treated with C3 (0, 5, 10, 20, 40 µg/ml for 24 h). DCs as stimulator cells were 30 Gy irradiated and added in graded doses into 1 x 105 allogeneic mononuclear responder cells from healthy volunteers in 96-well round-bottom plates (Falcon; Tokyo, Japan), and incubated for 5 days. [3H]Thymidine (Amersham) incorporation was measured after a 12-h pulsed labeling with 1 µCi/well. Results were shown as mean cpm of triplicates. In blocking experiments, sodium azide-free CD54 mAb (BD Biosciences, Mountain View, CA) at 10 µg/ml was added into the medium.
Flow cytometric analysis of surface molecules and intracellular cytokines
After C3 treatment (0, 10, 20, and 40 µg/ml), cell surface Ag
expression of DC was analyzed by dual immunofluorescence staining with
the following mAbs: FITC-conjugated mouse anti-CD14, HLA-DR (BD
Biosciences), CD11a (LFA-1), CD18 (integrin
2), CD29 (integrin
1), HLA-ABC (HLA class I; Serotec, Oxford,
U.K.), CD80 (B7-1; BD PharMingen, San Diego, CA); PE-conjugated mouse
anti-CD1a, CD40, CD83 (Immunotech, Marseille, France), CD11b
(integrin M), CD11c (integrin
X), CD54 (ICAM-1), HLA-DR (BD Biosciences),
CD49d (VLA-4), CD86 (B7-2; BD PharMingen); unlabeled CD11a (MHM-24;
DAKO Japan, Kyoto, Japan), CD18 (DAKO), CD58 (LFA-3; Serotec), CD54 (BD
Biosciences). mAb that recognizes activated epitope of CD11a (NKI-L16,
IgG1) (14) was kindly provided by C. G. Figdor
(University Hospital Nijmegen, Nijmegen, The Netherlands).
Stained samples were analyzed on a FACScan flow cytometer (BD
Biosciences).
Intracellular staining of IL-12 in DC was performed as previously
described (15). Immature DCs were stimulated with 1
µg/ml LPS for 18 h with or without C3. Brefeldin A (10
µg/ml; Sigma) was added for the last 2.5 h after LPS
stimulation. Then cells were fixed and permeabilized with PermeaFix
(Ortho, Tokyo, Japan), and subsequently stained with PE-conjugated
anti-human IL-12 mAb (p40/p70; BD PharMingen). Intracellular
cytokine production in T cells was analyzed, as previously reported
(16). Naive CD4+ T cells were
purified by CD4-negative selection from cord blood and cultured with
DCs for 6 days at 10:1 ratio. Then CD4+ T cells
were restimulated with PMA and Ionomycin (Sigma) for 6 h.
Brefeldin A (5 µg/ml) was added for the final 3 h. Intracellular
cytokines were stained with FITC-conjugated anti-IFN- (BD
Biosciences) and PE anti-IL-2 mAb (BD PharMingen).
ELISA
im-DCs were stimulated with 1 µg/ml LPS for 24 h. Then cell culture supernatants were assayed for IL-12 p70 by ELISA using OptEIA kit (BD PharMingen), according to the manufacturer’s instruction.
F-actin staining
To visualize F-actin in DC, m-DCs were fixed for 10 min with 3.7% formaldehyde/PBS and subsequently permeabilized in 0.1% Triton X-100/PBS for 40 min. Then cells were incubated with 0.2 µg/ml tetramethylrhodamine isothiocyanate (TRITC)-phalloidin (Sigma), which specifically binds F-actin (17), for 30 min. Cells were extensively washed in PBS and viewed on a confocal laser-scanning microscopy (Zeiss Axiovert 135, Oberkochen, Germany).
Scanning electron microscopy
Mature DCs or m-DC/C3 (DCs treated with exoenzyme C3) in 100 µl medium at 5 x 105/ml were cultured with the same volume of purified CD4+ T cells at 5 x 106/ml for 2 h. Then cells were very gently plated onto poly-L-lysine (Sigma)-coated glass coverslips and incubated for 30 min. Cells were prefixed in 1% glutaraldehyde/PBS for 15 min, washed three times, and postfixed for 25 min in 1% osmium tetroxide/PBS. Dehydration through ethanol and acetone was followed by critical point drying. Samples were mounted on scanning electron microscopy holders and spatter coated with gold, and observed using JSM-2000 scanning electron microscopy (JEOL, Tokyo, Japan).
DC-T cell conjugate formation assay
The adherence between DC and CD4+ T cell was examined by conjugate formation assay, using flow cytometer (18). CD4+ T cells and DCs (5 x 105/ml) were labeled respectively with 2 µM green fluorescent PKH-2 and red fluorescent PKH-26 (Sigma) at 25°C for 5 min (19). After washings, CD4+ T cells and DCs were mixed at a 3:1 ratio in tubes and were allowed to settle for 20 min on ice. The tubes were incubated at 37°C for 10 min, vortexed mildly, and transferred into medium on ice. Conjugates were identified as events that gave a positive signal for both PKH-2 and PKH-26. A single population of labeled cells was used to adjust instrument settings before conjugate analysis. Samples of cells mixed just before analysis at 4°C were used as negative controls. PMA-stimulated DCs were used as a positive control (20). PMA was added at 50 nM just before the beginning of assay as a positive control.
Statistical analysis
ANOVA and unpaired two-tailed t tests were used to determine statistical significance of the data.
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Results |
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TopAbstractIntroductionMaterials and MethodsResultsDiscussionReferences |
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Exoenzyme C3 from C. botulinum has been reported to ADP
ribosylate and inactivate Rho by binding to an asparagine in the
effector domain of Rho (21). Although T cells and other
cell types may need electroporation or microinjection to
introduce C3 into cells (22), C3 can enter into intact
monocytic cells and inactivate Rho without manipulation
(8). No report to introduce C3 into DC has been published
to date. To investigate whether or not C3 can enter into intact m-DC,
we performed ADP-ribosylation assay, as described (7).
Mature DC/C3 at 20 µg/ml were unable to incorporate
[32P]NAD in vitro, suggesting the majority of
the Rho proteins had already been ribosylated by C3 (Fig. 1
A). Lower concentration of C3
(5 µg/ml) could not completely ribosylate Rho in situ, because a
faint signal was detectable (Fig. 1A). The result indicates
that Rho is ADP ribosylated in DC simply by adding exoenzyme C3 into
the culture medium. C3 itself did not affect DC viability after 1–5
days of incubation, when checked by trypan blue dye exclusion test
(Fig. 1B).
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Cultured m-DC has many fine needle-like dendrites in the cellular
periphery (Fig. 2, A and
E). After 24-h treatment with 40 µg/ml C3, fine
needle-like dendrites disappeared. Instead, shrunk and relatively thick
membrane processes were observed (Fig. 2, B and
E). Cell size did not change, and more than half of the
cells had long filopodial extensions. Y-27632-treated DC (DC/Y) at 30
µM for 30 min showed marked morphological changes; almost all
dendrites disappeared, and large membrane expansion newly emerged (Fig. 2, C and E). Because these processes seemed
membrane ruffling that was of folded and shrunk membrane structure, we
performed scanning electron microscopy to distinguish these membrane
processes. Similarly to May-Giemsa staining, DC had many fine and
straight dendrites (Fig. 2D, left). However,
DC/C3 did not have such dendrites. Instead, shrunk processes seemed to
be ruffles of the membrane (Fig. 2D, right). C3
was active for >5 days because the shape of m-DCs after 5-day
incubation with C3 was same as compared with 24-h treated ones. We also
observed the same morphological changes when im-DCs were pretreated
with C3 (40 µg/ml, 24 h), then subsequent maturation was induced
by TNF- for 2 days (data not shown). The result indicates that C3
can affect both immature and mature stages of DC. The viability of
m-DC/Y was the same as untreated m-DC (data not shown).
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Because Rho exhibits various functions through actin
polymerization (8), we postulated that the drastic
morphological changes in DC induced by C3 or Y-27632 would be secondary
to the inhibition of actin polymerization. Therefore, we examined
polymerized actin by TRITC-phalloidin staining. First of all, we
examined F-actin distribution at differentiation stages from Mo to
m-DC. Mo had two types of actin: subcortical actin band in a high plane
of focus, and circular actin swirls in a low plane, directly above the
attached plasma membrane (8). In im-DC, subcortical actin
band irregularly distributed in broad, many sheet-like structures at
cellular periphery (data not shown). Mature DC had strong staining at
cellular margin and many fine-needle like dendrites (Fig. 3A). DC/C3 showed that
F-actin-positive dendrites were lost and shrunk membrane processes were
negative for TRITC-phalloidin (Fig. 3B). In DC/Y, large
membrane expansion emerged with disappearing dendrites; F-actin
staining was markedly reduced at cellular periphery (Fig. 3C). Preincubation with cytochalasin D (2 µM, 3 h), a
specific inhibitor of actin polymerization, before F-actin staining
gave similar findings that the amount of F-actin was reduced (data not
shown). These results demonstrated that reduction of fine needle-like
dendrites by C3 and Y-27632 is secondary to inhibition of actin
polymerization.
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As C3 could irreversibly inactivate Rho and work for 5 days, as
described above, 5-day MLR was thought to be applicable to examine
whether or not C3 may affect the allogeneic T cell-stimulatory
capacity. [3H]Thymidine incorporation was
markedly suppressed C3 dose dependently when allogeneic T cells were
stimulated with C3-treated m-DC (Fig. 4).
Up to 80% reduction of allostimulatory capacity was observed in DC/C3
at 40 µg/ml. In time-dependency experiments, there was no significant
difference in the duration of C3 treatment (2–5 days; data not shown).
HLA disparity between responders and stimulators may affect the MLR
activity (13). Because we did not perform HLA typing in
our experiments, we repeated MLR in different combinations of
responders and stimulators with reproducible results (n
= 3, data not shown). As to the reversibility of functional and
morphological changes, functional and morphological changes by C3
treatment were preserved, whereas DC/Y restored to normal after 24
h (data not shown).
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Because Rho is known as a key regulator of cell adhesion, we
investigated the DC-T cell interaction by two methods. First, scanning
electron microscopy was performed to evaluate the physical interaction
between DC and CD4+ T cell. Fig. 5A shows that control DC could
interact with CD4+ T cells by their membrane
processes and veil, as reported (23), when DCs were
cocultured with allogeneic CD4+ T cells for
2 h. However, DC/C3 with reduced dendrites could react with
CD4+ T cells less efficiently (Fig. 5A). This suggests that physical
DC-CD4+ T cell interaction is insufficient when
Rho is inactive in DC. In conjugate formation assay (18),
as highest percentage of conjugated DCs of total DCs with
CD4+ T cells was observed after 7- to 12-min
incubation, all experiments were done after 10-min incubation of these
cells. PMA-treated DCs were used as a positive control. In control
m-DCs, 12.8 ± 1.7% DCs adhered to CD4+ T
cell, and 9.4 ± 1.9% in m-DC/C3 (Fig. 5B,
p = 0.04). Similar to basal adhesion, PMA-stimulated
m-DC/C3 exhibited the lower level of conjugation efficiency compared
with that of m-DC (12.4 ± 2.4 vs 18.8 ± 3.7,
p = 0.03). The results suggested that, when stimulated
with PMA, untreated control DCs had higher capacity of
DC-CD4+ T cell conjugation than that of m-DC/C3
(p = 0.03, Fig. 5B). Collectively,
C3 can affect both basal and activated adhesion between m-DC and
CD4+ T cell.
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Because allostimulatory capacity of DC was significantly inhibited
in C3-treated DC, we examined surface molecules that might be related
to allostimulation. C3 was added into m-DCs at graded concentrations
(0, 10, 20, and 40 µg/ml). Consistent with the previous reports
(11, 24, 25), m-DCs were strongly positive for HLA class I
and II, CD86 (B7-2), CD54 (ICAM-1), and CD11c. Majority of DCs were
positive for CD40, CD1a, CD58, and CD29 (integrin
1 chain), and some were positive for CD80
(B7-1), CD83, CD18 (integrin 2 chain), CD11b,
and CD49d. C3 treatment did not alter the expression level of these Ags
(Fig. 6). Mature DCs induced from
C3-treated (40 µg/ml, 24 h) im-DCs showed the same
immunophenotype as compared with that of C3-treated m-DCs (data not
shown). Mo expressed high level of CD11a (MHM24), and most were
positive for activated epitope of CD11a recognized by NKI-L16, which is
strongly associated with adhesion (14, 26). However,
expressions of both MHM24 and NKI-L16 decreased in parallel with the
maturation from Mo to m-DC, and C3 treatment did not affect expression
of NKI-L16 (Fig. 5
C). Inhibition of CD54 in MLR partially
reduced [3H]thymidine incorporation to the same
level as in C3 (10 µg/ml)-treated m-DCs (Fig. 5D).
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To further evaluate the impairment of T cell-stimulatory capacity
of DC/C3, we analyzed intracellular IL-12 production of DC. By 21-h
stimulation with LPS, intracellular IL-12-positive DCs were increased
approximately twice higher than that of untreated DCs by preincubation
with C3 before adding LPS (Fig. 7A). Similarly, IL-12 p70 in
the supernatant was increased by C3 when measured by ELISA (Fig. 7B). To confirm the effect of enhanced IL-12 production, we
examined the capacity of Th1 polarization for naive
CD4+ T cells. Naive CD4+ T
cells cocultured with m-DC/C3 contained 27.5% of IFN--positive
cells, whereas im-DCs and m-DCs had 4.7% and 13.4%, respectively
(Fig. 7C, left lower panel). Exogenous IL-12
directed T cells toward Th1 (IFN-) sufficiently in each condition
(Fig. 7C, right lower panel). m-DC/C3
significantly reduced the proportion of IL-2-producing T cells as
compared with that of untreated m-DC (Fig. 7C, left
upper panel). However, this differential effect disappeared by the
addition of exogenous IL-12 into the culture medium (Fig. 7C, right upper panel).
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Discussion |
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TopAbstractIntroductionMaterials and MethodsResultsDiscussionReferences |
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It is suggested that characteristic shapes of DCs, including dendrite
and veil, are important to make interaction effectively and to keep
contact area widely (1). Large membrane expansion is able
to wrap up CD4+ T cells and makes strong physical
interaction between them (23). The scanning electron
microscopy data showed that Rho dysfunction led to decreased physical
interaction between DC and CD4+ T cells,
suggesting that Rho plays an important role in controlling interaction
through regulating actin-mediated morphological change and motility.
The fact that large membrane expansion appeared only 30 min after
inhibiting p160ROCK may suggest that Rho-p160ROCK system contributes to
change wide-contacting area when DCs interact with T cells. In NIH-3T3
cells, C3 treatment induces formation of filopodia (4); in
contrast, membrane protrusions induced by Rho in fibroblasts are
closely related to Rho dependent (28). These reports
suggest that Rho-related morphological changes are not necessarily
uniform in different cell types and situations. In the signaling
pathways from Rho to the actin cytoskeleton, the main target is
p160ROCK that finally up-regulate actomyosin contractility
(29). Therefore, the inhibition of P160ROCK induces large
membrane expansion in DC by reduction of cell tension (Fig. 2C), and therefore, Rho-p160ROCK system positively regulates
dendrite formation in DC.
C3 treatment significantly inhibited T cell-stimulatory capacity of DCs
in allogeneic MLR (Fig. 4). We tried to address the issue of its
inhibitory mechanism in several ways. Despite our speculation, C3
treatment did not down-regulate cell surface Ags, including HLA,
costimulatory, and adhesion molecules, and did not disturb the
phenotypic maturation from im-DC to m-DC (Fig. 6). Fig. 5 (conjugate
formation, expression of NKI-L16, and blocking experiment in MLR)
suggests that Rho is associated with initial DC-T cell interaction. The
main partners of DC-T cell interaction are LFA-1 on T cells and ICAM-1
on DCs. LFA-1 provides an important costimulatory signal for
TCR-mediated activation of resting T cells (30, 31).
Adhesion molecules on DCs are closely related to T cell-stimulatory
capacity (32). Conjugate formation data in Fig. 5 suggest
that C3 may affect both basal and activated adhesion. Van Kooyk et al.
(14) reported that PMA activated LFA-1 immediate early in
T cell activation. However, the expression of both LFA-1 and activated
LFA-1 is decreased in m-DC (Fig. 5C), suggesting that LFA-1
on DC may not contribute to DC-T cell interaction in large part.
Therefore, we speculate that the function of ICAM-1 on DCs may be
inhibited by Rho inactivation. Indeed, Rho positively controls the
function of ICAM-1 by protein-protein interaction, but not
transcriptional level in endothelial cells (33). In HUVEC,
ICAM-1-mediated adhesion to Mo is inhibited by C3, and its inhibition
is mainly associated with receptor clustering of ICAM-1 at contacting
point (34). In addition, CD54 mAb-blocking test induced
the same level of inhibition of [3H]thymidine
incorporation as in DC/C3 (Fig. 5D). Based on these data, it
is likely that Rho regulates the function of ICAM-1 in DCs for
interaction to T cell.
We demonstrated that C3 treatment resulted in augmented LPS-induced
IL-12 production in DCs that has not been reported previously (Fig. 7, A and B). Its biological effect was assessed by
the interaction with T cells, and was confirmed by the increased
intracellular IFN- staining of naive CD4+ T
cell when cultured with DC/C3. Although IFN--producing T cells
increased, IL-2-producing T cells significantly decreased in DC/C3-T
cell interaction (Fig. 7C). By adding exogenous IL-12 into
the medium, IFN--producing Th1 cells were increased, whereas there
was no significant difference among IL-2-positive cells. Investigators
reported that the inhibition of costimulatory molecules reduced IL-2,
but not IFN- production in activated T cell (35, 36),
and that IL-12 promoted Th1 differentiation, but did not rescue IL-2
production and DNA synthesis in anergic T cell (37). Our
data, together with these reports, suggest that efficiency of Th1
polarization may be related to the soluble factors (mainly IL-12), but
T cell activation (IL-2 production and DNA synthesis) may be regulated
by the cell-to-cell interaction.
DCs may play an important role in various diseases, including infections, autoimmune diseases, and graft-vs-host disease (GVHD) in allogeneic stem cell transplantation (38, 39, 40). Among many strategies to prevent GVHD (41, 42), the suppression of DC function seems to be quite important. According to our data, Rho may be a possible target in controlling GVHD, because C3 may specifically inhibit these APCs in vivo and it may not enter cells freely except Mo and DC. In this study, although we cannot exclude the possibility that C3 may be affecting different functions in our different experiments, we demonstrate that characteristic functions of DC, such as changing shape, adhesion, IL-12 production, and T cell stimulation, are definitely regulated by Rho in vitro. Further study will be required to elucidate the role of Rho in vivo in clinical situations.
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Acknowledgments |
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Footnotes |
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2 Address correspondence and reprint requests to Dr. Eiichi Azuma, Department of Clinical Immunology, Mie University School of Medicine, 2-174 Edobashi, Tsu, Mie 514-8507, Japan. E-mail address: e-azuma{at}clin.medic.mie-u.ac.jp
3 Abbreviations used in this paper: DC, dendritic cell; DC/C3, DC treated with exoenzyme C3; DC/Y, Y-27632-treated DC; GVHD, graft-vs-host disease; im-DC, immature DC; m-DC, mature DC; Mo, monocyte; ROCK, Rho-associated coiled coil-containing kinase; TRITC, tetramethylrhodamine isothiocyanate.
Received for publication October 18, 2000. Accepted for publication July 19, 2001.
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I. Lindner, M. A. Kharfan-Dabaja, E. Ayala, D. Kolonias, L. M. Carlson, Y. Beazer-Barclay, U. Scherf, J. H. Hnatyszyn, and K. P. Lee Induced Dendritic Cell Differentiation of Chronic Myeloid Leukemia Blasts Is Associated with Down-Regulation of BCR-ABL J. Immunol., August 15, 2003; 171(4): 1780 - 1791. [Abstract] [Full Text] [PDF]
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T. Wachter, M. Averbeck, H. Hara, J. P. Tesmann, J. C. Simon, C. C. Termeer, and R. W. Denfeld Induction of CD4+ T Cell Apoptosis as a Consequence of Impaired Cytoskeletal Rearrangement in UVB-Irradiated Dendritic Cells J. Immunol., July 15, 2003; 171(2): 776 - 782. [Abstract] [Full Text] [PDF]
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P.-L. Tharaux, R. C. Bukoski, P. N. Rocha, S. D. Crowley, P. Ruiz, C. Nataraj, D. N. Howell, K. Kaibuchi, R. F. Spurney, and T. M. Coffman Rho Kinase Promotes Alloimmune Responses by Regulating the Proliferation and Structure of T Cells J. Immunol., July 1, 2003; 171(1): 96 - 105. [Abstract] [Full Text] [PDF]
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 Y. Yanagawa and K. Onoe CCR7 ligands induce rapid endocytosis in mature dendritic cells with concomitant up-regulation of Cdc42 and Rac activities Blood, June 15, 2003; 101(12): 4923 - 4929. [Abstract] [Full Text] [PDF]
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T. Senga, S. Iwamoto, T. Yoshida, T. Yokota, K. Adachi, E. Azuma, M. Hamaguchi, and T. Iwamoto LSSIG is a novel murine leukocyte-specific GPCR that is induced by the activation of STAT3 Blood, February 1, 2003; 101(3): 1185 - 1187. [Abstract] [Full Text] [PDF]
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