Previous Article | Next Article 
Infection and Immunity, July 2001, p. 4667-4672, Vol. 69, No. 7
0019-9567/01/$04.00+0 DOI: 10.1128/IAI.69.7.4667-4672.2001
Copyright © 2001, American Society for Microbiology. All rights reserved.
Expression of Genes Encoding Th1 Cell-Activating Cytokines and
Lymphoid Homing Chemokines by Chlamydia-Pulsed Dendritic Cells
Correlates with Protective Immunizing Efficacy
Jennifer H.
Shaw,1
Vernon R.
Grund,2
Luke
Durling,1 and
Harlan
D.
Caldwell1,*
Laboratory of Intercellular Parasites, National Institute
of Allergy and Infectious Diseases, National Institutes of Health,
Rocky Mountain Laboratory, Hamilton, Montana
59840,1 and Department of Pharmaceutical
Sciences, University of Montana, Missoula, Montana
598012
Received 26 February 2001/Returned for modification 9 April
2001/Accepted 16 April 2001
 |
ABSTRACT |
We studied the expression of cytokines, chemokines, and chemokine
receptors by the RNase protection assay in chlamydia-pulsed dendritic
cells to better understand their potent anti-chlamydial immunizing
properties. We found that chlamydia-pulsed dendritic cells express a
complex profile of inflammatory and immunomodulatory molecules. These
include CCR-7, interleukin-12, and interferon-induced protein 10, molecules that might influence the homing of pulsed dendritic cells to
the site of chlamydial infection and the induction of a local
protective CD4+ Th1 cellular immunity.
| |
TEXT |
Chlamydia trachomatis is
an obligatory intracellular bacterial parasite that infects the
oculogenital mucosal epithelium, causing trachoma, the world's leading
cause of preventable blindness, and sexually transmitted diseases.
Pelvic inflammatory disease is a serious sequalae of C. trachomatis infection of the female genital tract that can result
in tubal blockage, infertility, or ectopic pregnancy (2, 4, 8,
13). The development of an efficacious vaccine against C. trachomatis oculogenital infection is likely to be key to the
control of both trachoma and chlamydial sexually transmitted diseases.
Despite considerable effort, however, there has been little favorable
progress toward this end. Conventional vaccination approaches have
produced disappointing results in their abilities to prevent infection
of the mouse female genital tract (12, 14, 19), despite a
modicum of success in controlling chlamydial infection of the
respiratory tract (20). Solid protective immunity to
genital rechallenge has been achieved only by infection or adoptive
immunization with dendritic cells (DC) pulsed ex vivo with inactivated
whole chlamydial organisms (6, 18). Interestingly, mice
immunized with chlamydia-pulsed DC exhibit equivalent levels of
protective immunity to that in mice that have spontaneously resolved a
primary genital infection (18). Both infection-mediated
protective immunity and immunity elicited following adoptive transfer
of antigen-pulsed DC correlate with a chlamydia-specific
CD4+ Th1-biased immune response characterized by the
secretion of high levels of gamma interferon from local and splenic
CD4+ T cells (6, 18). Recent studies have also
indicated an important cooperative role for both CD4+ T
cells and B cells in recall immunity in the murine model; however the
mechanism(s) that mediates this cooperative effector function has not
been described (11). Clearly, the use of ex vivo
antigen-pulsed DC as a practical chlamydial vaccine is unsuited for use
in humans. Nevertheless, the ability of ex vivo antigen-pulsed DC to
elicit solid antichlamydial protective immunity at the genital mucosae is gratifying because it demonstrates that a more complete
understanding of chlamydia-DC interactions may provide important
information applicable to the development of a conventional
antichlamydial vaccine.
In this work we have investigated cytokine, chemokine, and chemokine
receptor gene expression in chlamydia-pulsed DC by the RNase protection
assay (RPA). Our findings show that populations of chlamydia-pulsed DC
that provide solid protective immunity following adoptive transfer to
naive mice up regulate genes that mediate DC homing to lymphatic
tissues and the recruitment and activation of T cells.
Chlamydiae, mice, and DC.
The mouse pneumonitis (MoPn)
strain of C. trachomatis was grown in HeLa 229 cells.
Infectious elementary bodies (EBs) were purified by density gradient
centrifugation, and infection-forming units (IFU) were determined as
previously described (3). Female C57BL/10 mice were
purchased from The Jackson Laboratory (Bar Harbor, Maine) and used
between 8 and 12 weeks of age. Bone marrow-derived DC were generated
from C57BL/10 female mice (6 to 12 weeks old) using a modified version
of the Inaba technique (7). Briefly, femurs were removed
from mice and bone marrow cells were flushed from the femurs and
cultured in Iscove modified Dulbecco medium (IMDM) (Life Technologies)
supplemented with 10% fetal bovine serum, 10 µg of gentamicin
sulfate per ml, 10 ng of granulocyte-macrophage colony-stimulating
factor (GM-CSF), per ml, and 103 U of interleukin-4 (IL-4)
(PharMingen) per ml at 2 × 106 cells/ml in 100-mm
tissue culture dishes. On day 3 of culture, nonadherent cells were
removed and fresh medium containing GM-CSF and IL-4 was added. On day 5 of culture, DC were separated from the remaining contaminating
macrophages by transferring the nonadherent and loosely adherent DC
cells to new culturing plates and were then incubated at 37°C for
2 h. This procedure was repeated, and nonadherent DC were further
purified by density gradient centrifugation in metrizamide gradients
(Sigma) prepared in cell culture medium. The purity of density
gradient-purified DC was assessed by flow cytometry (Becton Dickinson)
after staining with anti-I-Ab, anti-CD86, anti-CD40,
anti-CD11b, anti-Gr1, anti-CD3, anti-CD19, and anti-Pan NK. Isolated DC
showed positive staining for I-Ab, CD86, CD40, and CD11b
and were negative for CD3, CD19, and Gr-1 (data not shown).
DC cultured for 5 days, panned, and isolated from density gradients
were washed and plated at 2.5 × 106 DC/well in
six-well tissue culture plates containing culture medium supplemented
with 10 ng of GM-CSF per ml. DC were divided into the following groups
and treated as follows: (i) no treatment (IMDM alone); (ii) 10 ng of
lipopolysaccharide (LPS) (Escherichia coli strain O26:B6
[Sigma]) per ml, which served as a positive control for DC
activation; (iii) latex beads (2.5% solids-latex, 0.585 µm in
diameter [Polysciences, Inc.]), which served as a negative control
for gene expression induced by endocytosis; and (iv) heat-inactivated
(56°C for 30 min) MoPn EBs. LPS, latex beads, and EBs were all
diluted in IMDM and the material added directly to the plates
containing DC. The materials were mixed with DC by gently swirling the
plates. The plates were then incubated at 37°C for 12 h, and DC
were harvested and prepared for flow cytometry, RPA, or adoptive immunization.
Immunization with chlamydia-pulsed DC.
Female mice (five to
eight animals per group) were immunized by the subcutaneous (s.c.),
intraperitoneal (i.p.), or intravenous (i.v.) route. Treated or
untreated DC were washed in cell culture medium without FBS and
resuspended in Hanks balanced salt solution (HBSS) at 2.5 × 107 cells/ml. A 0.2-ml volume of these suspensions (5 × 106 cells) was used to inoculate mice by the different
routes described above. Heat-inactivated EBs (2.5 × 108, an equivalent number of heat-inactivated HK EBs to
that used to pulse DC) resuspended in 0.2 ml of cell culture medium
without FBS or mice receiving no immunization were used as negative
controls. A second immunization was administered 14 days after the
primary immunization. One week following the second immunization, mice were injected s.c. with 2.5 mg of medroxyprogesterone acetate (Depo-Provera; Upjohn Co., Kalamazoo, Mich.) in 0.1 ml of saline to
synchronize estrous cycles. Seven days later, the mice were challenged
by injecting 5 µl of chlamydial MoPn (150 IFU, 10 50% infective
doses) 10mM phosphate (pH 7.2) containing 0.25 M sucrose and 5 mM
L-glutamic acid (SPG) directly into the vaginal vault by
using a narrow-bore pipette. Mice that had resolved a primary chlamydial genital infection were rechallenged vaginally and served as
a positive (infection immune) control. Protection was assessed by
quantifying recoverable infectious organisms from cervicovaginal swabs
at intervals following infectious challenge (days 3, 5, 7, 10, 14, 21, and 28). Briefly, mice were cultured by swabbing the vaginal vault
(Calgiswab type 1; Hardwood Products Co., Guilford, Maine), samples
were vortexed vigorously, and diluted in SPG. HeLa cells were
inoculated with all dilutions in triplicate in 96-well tissue culture
plates. The plates were centrifuged for 1 h at 700 × g and then rocked at 37°C for 30 min. Cells were washed with
HBSS three times and fed 100 µl of minimal essential medium
supplemented with 10% FBS and cycloheximide (10 ng/ml) per well.
Cultures were incubated for 24 h and fixed in methanol. Chlamydial
inclusions were detected by indirect-immunofluorescence staining using
the chlamydia-LPS genus-specific monoclonal antibody EVI-H1 and
quantified as IFU.
RPA.
DC total RNA was harvested by the TriZol RNA isolation
method (Life Technologies) at 2, 12, 24, 48, and 72 h
posttreatment. A multiprobe RPA system (PharMingen) was used to detect
DC expression of macrophage inflammatory protein 1
(MIP-1),
MIP-1
, MIP-2, MIP-3, MIP-3, monocyte chemotactic protein 1, lymphotactin, eotaxin, RANTES (regulated on activation, normal T-cell
expressed and secreted), interferon-induced protein 10 (IP-10), T-cell
activation gene 3 (TCA-3), chemokine receptor 1 (CCR1), CCR1, CCR3,
CCR4, CCR5, CCR6, CCR7, IL-1, IL-1, IL-1 receptor antagonist,
IL-6, IL-10, IL-12p35, IL-12p40, IL-18, gamma interferon, tumor
necrosis factor alpha (TNF-), migration inhibitory factor (MIF), and
constitutive genes (internal controls) L32 and
glyceraldehyd-3-phosphate dehydrogenase (GAPDH). Briefly, DNA templates
encoding exonic sequences of the genes of interest were fused to a T7
promoter and used for T7 RNA polymerase-directed synthesis of highly
specific 32P-labeled antisense RNA probes. Labeled RNA
probes were hybridized in excess overnight at 56°C with 4 µg of
target DC mRNA. The following day, free probe and other single-stranded
RNA molecules were digested with RNases T1 and A. The
remaining "RNase-protected" probes were purified, resolved on
denaturing polyacrylamide gels based on size, and imaged by
autoradiography. Protected probes at the appropriate sizes represent
specific DC mRNA.
Intravenous immunization with chlamydia-pulsed DC is the optimum
route for eliciting protective immunity.
We initially studied
whether the route of immunization with chlamydia-pulsed DC had an
effect on the level of antichlamydial protective immunity generated at
the genital mucosae. We found that i.v. immunization with
chlamydia-pulsed DC was superior to either the s.c. or i.p. route (Fig.
1). Compared to naive control animals,
mice immunized i.v. with chlamydia-pulsed DC exhibited a 5.6-log-unit
reduction in infectious burden following chlamydial challenge. Five of
the eight challenged mice in the i.v.-immunized group were culture
negative 7 days postchallenge, and the three culture-positive mice
exhibited a marked reduction in chlamydial burden compared to naive
controls. Interestingly, this level of protection was equivalent to
that found in mice that had resolved a primary genital infection and
were then rechallenged (4.6-log-unit reduction). Mice immunized by the
s.c. or i.p. route exhibited only marginal levels of protection (s.c. = 0.3 log unit) or were partially protected (i.p. = 2.4 log units),
respectively. There was also marked variation in the level of
protective immunity generated in mice immunized by the i.p. route;
three of five mice were highly protected, whereas no protection was
observed the other two. Mice immunized i.v. with heat-inactivated EBs
alone and challenged intravaginally were not protected.
View larger version (22K):
[in this window]
[in a new window]
|
FIG. 1.
Intravenous delivery of DC pulsed with nonviable
chlamydiae elicits strong protective immunity against infectious
intravaginal challenge. Mice received either no immunization (naive),
150 IFU of C. trachomatis EBs (MoPn strain) delivered
intravaginally (infected), 2.5 × 108 heat-inactivated
MoPn EBs in 0.2 ml of HBSS delivered i.v. (HK EB), or 5 × 106 DC pulsed with 2.5 × 108
heat-inactivated MoPn EBs (DC + HK EB) delivered in 0.2 ml of HBSS
s.c., i.p., and i.v. One week following the booster immunization, all
mice were challenged intravaginally with 150 IFU of MoPn EBs in 5 µl
of SPG. Protection was assessed by quantifying the chlamydial IFU
recovered from cervicovaginal swabs (shown on the x axis).
Day 4 postchallenge data are shown here. Triangles represent individual
mice.
|
|
We next assayed the sera of immunized mice by enzyme-linked
immunosorbent assay ELISA for chlamydia-specific immunoglobulin
G1
(IgG1) and IgG2a antibodies as a way of indirectly ascertaining
whether
they generated a CD4
+ Th1 immune response (Fig.
2). All mice in the infected and
rechallenged
group and the i.v.-immunized group produced a
chlamydia-specific
IgG2a response indicative of a type 1 CD4
+ response. In contrast, only three of the five mice
immunized
by the i.p. route had detectable antichlamydial antibodies
that
were exclusively of the IgG2a (Th1) isotype. The mice with
chlamydia-specific
IgG2a serum antibodies were the same animals that
exhibited significant
levels of protective immunity following
intravaginal challenge
(Fig.
1). All mice immunized s.c. with
chlamydia-pulsed EBs and
which were not protected following chlamydial
challenge were negative
by ELISA for chlamydial antibody (data not
shown). In conclusion,
the results clearly demonstrate that delivery of
chlamydia-pulsed
DC by the i.v. route is superior for eliciting a
protective immune
response against chlamydial infection of the genital
mucosae.
The reasons for these findings are not known, but it is
possible
that i.v.-administered antigen-pulsed DC home efficiently to
regional
or mesenteric lymph nodes, where they interact with T cells
that
are capable of homing to the genital mucosae.
View larger version (12K):
[in this window]
[in a new window]
|
FIG. 2.
Serum antibody titers following infection or
immunization with chlamydia-pulsed DC. Sera were collected from naive
mice, infected mice (35 days postinfection), and 14 days following two
immunizations (administered 14 days apart) with chlamydia-pulsed DC
(DC + HK EB) by i.v. and i.p. injection. Chlamydia-specific IgG1
and IgG2a titers were determined by ELISA. Naive mice did not elicit a
chlamydia-specific IgG1 or IgG2a response. Infected mice elicited a
predominantly IgG2a response. All mice immunized with chlamydia-pulsed
DC by i.v. injection elicited a strong chlamydia-specific IgG2a and
IgG1 response with higher titers than did mice that had been infected
and resolved infection for 35 days. Three of the five mice immunized by
i.p. injection elicited a chlamydia-specific IgG2a response. Ovals
represent individual mice (solid ovals, IgG2a; open ovals, IgG1). Solid
horizontal bars indicate the mean absorbance. Absorbance is shown on
the y axis; 1:256 dilution of all sera is indicated on the
x axis.
|
|
Chlamydia-pulsed DC differentially express genes that promote DC
migration, activation, and recruitment of T cells.
The ability of
immature DC to traffic from peripheral tissues such as the epithelium
to draining regional lymph nodes is critical for the generation of an
immune response (1, 5, 15-17). DC migration to lymphatic
tissue is regulated by chemokines, chemokine receptors, and cytokines
(1, 21). To ascertain if chlamydia-pulsed DC expressed
immunomodulatory molecules that function in the homing and induction of
T-cell immunity, we used RPA to examine the kinetics of DC chemokine,
chemokine receptor, and cytokine gene expression following endocytosis
of chlamydiae. Untreated DC, DC treated with E. coli LPS,
and DC that had endocytosed 500-nm-diameter latex beads were included
in the assays as negative and positive controls and as a control for
induction of gene expression by the phagocytic process, respectively.
Genes that were up regulated are identified in the figures by the
boxes. The results show that MIP-1, MIP-2, TNF-, IL-1,
IL-1, and IL-1RA were expressed by 2 h after treatment with
chlamydiae as well as LPS and remained continuously expressed for as
long as 48 h (Fig. 3 and 4A and B). In contrast, MIP-3 and IL-12p40
were expressed at 12 h and showed similar continuous expression
(Fig. 3 and 4B). IP-10 and IL-6 were transiently expressed, being
detected at 12 h but not at 48 h (Fig. 3 and 4A). CCR1,
CCR1, CCR2, CCR3, CCR4, CCR5, and CCR6 were not expressed at any
time points following the uptake of chlamydial organisms (Fig.
5). Expression of CCR7 by DC was observed
under all culture conditions; however, only chlamydia-pulsed DC
expressed CCR7 at 48 h (Fig. 5). The ability of EBs to
dramatically up regulate the expression of such a large number of
proinflammatory and immunomodulatory molecules is impressive. At
present it is unknown what components of the organism might mediate
this response. An obvious candidate is chlamydial LPS; however, we do
not believe this to be the case because chlamydial LPS differs
structurally from the positive-control enteric LPS in that it possess
unusual long-chain fatty acids that are known to result in its low to undetectable endotoxic activity (10). Nevertheless, we
cannot exclude this possibility, and wed did not test chlamydial LPS directly because of the difficulty in purifying sufficient amounts of
the molecule from native chlamydial organisms.
View larger version (112K):
[in this window]
[in a new window]
|
FIG. 3.
DC pulsed with chlamydiae differentially express
chemokines important for recruitment and activation of T cells and
immature DC. RNA was harvested from DC for RPA analysis at 2, 12, 24, and 48 h following no treatment (NT) or treatment with LPS,
chlamydiae (heat-inactivated MoPn EBs), or latex beads. Unprotected
mRNA probes for selected chemokines are shown in the left-hand lane and
named along the y axis. Treatment groups and time points are
listed at the top of the gel. L32 and GAPDH are constitutive genes that
serve as internal controls. Boxed bands represent differentially
expressed genes. *, no mRNA detected.
|
|
View larger version (73K):
[in this window]
[in a new window]
|
FIG. 4.
DC pulsed with chlamydiae differentially express Th1
cytokines. RNA was harvested from DC for RPA analysis at 2, 12, 24, and
48 h following no treatment (NT) or treatment with LPS, chlamydiae
(heat-inactivated MoPn EBs), or latex beads. Unprotected mRNA probes
for selected cytokines are shown in the left-hand lane in A and B. Treatment groups and time points are listed at the top of the gels. L32
and GAPDH are internal controls. Boxed bands represent differentially
expressed genes. *, no mRNA detected.
|
|
View larger version (53K):
[in this window]
[in a new window]
|
FIG. 5.
Expression of CCR7 mRNA by chlamydia-pulsed DC. RNA was
harvested from DC for RPA analysis at 2, 24, and 48 h following no
treatment (NT) or treatment with heat-inactivated chlamydial EBs or
latex beads (LB). Unprotected probes for chemokine receptors 1 to 7 are
shown in the left-hand lane. The boxed band indicates increased
longevity of expression of the CCR7 mRNA by DC pulsed with nonviable
chlamydiae for 48 h.
|
|
In summary, we show that DC pulsed with nonviable chlamydiae that
generate a potent protective immune response following i.v.
adoptive
transfer induce a wide spectrum of immunomodulatory genes
that includes
genes encoding MIP-1
, MIP-2, MIP-3
, TNF-
, IL-1
,
IL-1
,
IL-1RA, IP-10, IL-6, IL-12p40, and CCR7. We believe that
the most
notable of these genes, in terms of the protective immunizing
capabilities of antigen-pulsed DC, are likely to be CCR7, IL-12,
and
IP-10. The stable expression of CCR7 by chlamydia-pulsed DC
may extend
the duration of DC maturation following adoptive transfer,
thereby
allowing additional time for migration to local lymph
nodes. Expression
of IP-10 and IL-12 by chlamydia-pulsed DC, albeit
transient, implies an
ability to specifically traffic effector
T cells to the genital mucosae
and potentially promote their differentiation
toward a CD4
+
Th1 phenotype, a model that has recently been shown to function
in the
generation of protective immunity against the obligate
intracellular
eukaryotic pathogen
Toxoplasma gondii (
9).
Clearly,
however, these conclusions need to be supported by further
experimentation
that would include monitoring DC migration to the iliac
and mesenteric
lymph nodes and in vivo antibody-mediated depletion of
IL-10 following
adoptive immunization. Nevertheless, this work clearly
demonstrates
that DC pulsed with inactivated chlamydiae and
administered i.v.
elicit equivalent levels of protective immunity to
that achieved
by infection itself. These findings imply that eliciting
protective
immunity at the genital mucosae by more conventional vaccine
strategies
is feasible but will require both the identification of
chlamydial
protective antigens and the development of adjuvants capable
of
modulating local T-cell responses that favor the induction of
CD4
+ type 1
immunity.
| |
FOOTNOTES |
*
Corresponding author. Mailing address: Laboratory of
Intercellular Parasites, National Institute of Allergy and Infectious Diseases, NIH Rocky Mountain Laboratory, 903 South 4th St., Hamilton, MT 59840. Phone: (406) 363-9333. Fax: (406) 363-9355. E-mail: hcaldwell{at}niaid.nih.gov.
Editor:
W. A. Petri Jr.
| |
REFERENCES |
| 1.
|
Banchereau, J.,
F. Briere,
C. Caux,
J. Davoust,
S. Lebecque,
Y. J. Liu,
B. Pulendran, and K. Palucka.
2000.
Immunobiology of dendritic cells.
Annu. Rev. Immunol.
18:767-811[CrossRef][Medline].
|
| 2.
|
Brunham, R. C.,
R. Peeling,
I. Maclean,
M. L. Kosseim, and M. Paraskevas.
1992.
Chlamydia trachomatis-associated ectopic pregnancy: serologic and histologic correlates.
J. Infect. Dis.
165:1076-1081[Medline].
|
| 3.
|
Caldwell, H. D.,
J. Kromhout, and J. Schachter.
1981.
Purification and partial characterization of the major outer membrane protein of Chlamydia trachomatis.
Infect. Immun.
31:1161-1176[Abstract/Free Full Text].
|
| 4.
|
Chow, J. M.,
M. L. Yonekura,
G. A. Richwald,
S. Greenland,
R. L. Sweet, and J. Schachter.
1990.
The association between Chlamydia trachomatis and ectopic pregnancy. A matched-pair, case-control study.
JAMA
263:3164-3167[Abstract/Free Full Text].
|
| 5.
|
Dieu, M. C.,
B. Vanbervliet,
A. Vicari,
J. M. Bridon,
E. Oldham,
S. Ait-Yahia,
F. Briere,
A. Zlotnik,
S. Lebecque, and C. Caux.
1998.
Selective recruitment of immature and mature dendritic cells by distinct chemokines expressed in different anatomic sites.
J. Exp. Med.
188:373-386[Abstract/Free Full Text].
|
| 6.
|
Igietseme, J. U.,
G. A. Ananaba,
J. Bolier,
S. Bowers,
T. Moore,
T. Belay,
F. O. Eko,
D. Lyn, and C. M. Black.
2000.
Suppression of endogenous IL-10 gene expression in dendritic cells enhances antigen presentation for specific Th1 induction: potential for cellular vaccine development.
J. Immunol.
164:4212-4219[Abstract/Free Full Text].
|
| 7.
|
Inaba, K.,
M. Inaba,
N. Romani,
H. Aya,
M. Deguchi,
S. Ikehara,
S. Muramatsu, and R. M. Steinman.
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].
|
| 8.
|
Jones, R. B.,
B. R. Ardery,
S. L. Hui, and R. E. Cleary.
1982.
Correlation between serum antichlamydial antibodies and tubal factor as a cause of infertility.
Fertil. Steril.
38:553-558[Medline].
|
| 9.
|
Khan, I. A.,
J. A. MacLean,
F. S. Lee,
L. Casciotti,
E. DeHaan,
J. D. Schwartzman, and A. D. Luster.
2000.
IP-10 is critical for effector T cell trafficking and host survival in Toxoplasma gondii infection.
Immunity
12:483-494[CrossRef][Medline].
|
| 10.
|
Kosma, P.
1999.
Chlamydial lipopolysaccharide.
Biochim. Biophys. Acta.
1455:387-402[Medline].
|
| 11.
|
Morrison, S. G.,
H. Su,
H. D. Caldwell, and R. P. Morrison.
2000.
Immunity to murine chlamydia trachomatis genital tract reinfection involves B cells and CD4+ T cells but not CD8+ T cells.
Infect. Immun.
68:6979-6987[Abstract/Free Full Text].
|
| 12.
|
Pal, S.,
K. M. Barnhart,
Q. Wei,
A. M. Abai,
E. M. Peterson, and L. M. de la Maza.
1999.
Vaccination of mice with DNA plasmids coding for the Chlamydia trachomatis major outer membrane protein elicits an immune response but fails to protect against a genital challenge.
Vaccine
17:459-465[CrossRef][Medline].
|
| 13.
|
Schachter, J.
1978.
Chlamydial infections.
N. Engl. J. Med.
298:428-434[Medline].
|
| 14.
|
Schnorr, K. L.
1989.
Chlamydial vaccines.
J. Am. Vet. Med. Assoc.
195:1548-1561[Medline].
|
| 15.
|
Shaffer, A. L.,
X. Yu,
Y. He,
J. Boldrick,
E. P. Chan, and L. M. Staudt.
2000.
BCL-6 represses genes that function in lymphocyte differentiation, inflammation, and cell cycle control.
Immunity
13:199-212[CrossRef][Medline].
|
| 16.
|
Sozzani, S.,
P. Allavena,
A. Vecchi, and A. Mantovani.
1999.
The role of chemokines in the regulation of dendritic cell trafficking.
J. Leukoc. Biol.
66:1-9[Abstract].
|
| 17.
|
Steinman, R. M.,
M. Pack, and K. Inaba.
1997.
Dendritic cells in the T-cell areas of lymphoid organs.
Immunol. Rev.
156:25-37[CrossRef][Medline].
|
| 18.
|
Su, H.,
R. Messer,
W. Whitmire,
E. Fischer,
J. C. Portis, and H. D. Caldwell.
1998.
Vaccination against chlamydial genital tract infection after immunization with dendritic cells pulsed ex vivo with nonviable chlamydiae.
J. Exp. Med.
188:809-818[Abstract/Free Full Text].
|
| 19.
|
Ward, M. E.
1992.
Chlamydial vaccines future trends.
J. Infect.
25(Suppl. 1):11-26.
|
| 20.
|
Zhang, D.,
X. Yang,
J. Berry,
C. Shen,
G. McClarty, and R. C. Brunham.
1997.
DNA vaccination with the major outer-membrane protein gene induces acquired immunity to Chlamydia trachomatis (mouse pneumonitis) infection.
J. Infect. Dis.
176:1035-1040[Medline].
|
| 21.
|
Zlotnik, A., and O. Yoshie.
2000.
Chemokines: a new classification system and their role in immunity.
Immunity
12:121-127[CrossRef][Medline].
|
Infection and Immunity, July 2001, p. 4667-4672, Vol. 69, No. 7
0019-9567/01/$04.00+0 DOI: 10.1128/IAI.69.7.4667-4672.2001
Copyright © 2001, American Society for Microbiology. All rights reserved.
This article has been cited by other articles:
-
Bilenki, L., Wang, S., Yang, J., Fan, Y., Jiao, L., Joyee, A. G., Han, X., Yang, X.
(2006). Adoptive Transfer of CD8{alpha}+ Dendritic Cells (DC) Isolated from Mice Infected with Chlamydia muridarum Are More Potent in Inducing Protective Immunity Than CD8{alpha}- DC. J. Immunol.
177: 7067-7075
[Abstract]
[Full Text]
-
Nagarajan, U. M., Ojcius, D. M., Stahl, L., Rank, R. G., Darville, T.
(2005). Chlamydia trachomatis Induces Expression of IFN-{gamma}-Inducible Protein 10 and IFN-{beta} Independent of TLR2 and TLR4, but Largely Dependent on MyD88. J. Immunol.
175: 450-460
[Abstract]
[Full Text]
-
Rey-Ladino, J., Koochesfahani, K. M., Zaharik, M. L., Shen, C., Brunham, R. C.
(2005). A Live and Inactivated Chlamydia trachomatis Mouse Pneumonitis Strain Induces the Maturation of Dendritic Cells That Are Phenotypically and Immunologically Distinct. Infect. Immun.
73: 1568-1577
[Abstract]
[Full Text]
-
Gervassi, A., Alderson, M. R., Suchland, R., Maisonneuve, J. F., Grabstein, K. H., Probst, P.
(2004). Differential Regulation of Inflammatory Cytokine Secretion by Human Dendritic Cells upon Chlamydia trachomatis Infection. Infect. Immun.
72: 7231-7239
[Abstract]
[Full Text]
-
Steele, L. N., Balsara, Z. R., Starnbach, M. N.
(2004). Hematopoietic Cells Are Required to Initiate a Chlamydia trachomatis-Specific CD8+ T Cell Response. J. Immunol.
173: 6327-6337
[Abstract]
[Full Text]
-
Johnson, R. M.
(2004). Murine Oviduct Epithelial Cell Cytokine Responses to Chlamydia muridarum Infection Include Interleukin-12-p70 Secretion. Infect. Immun.
72: 3951-3960
[Abstract]
[Full Text]
-
Nakamura, Y., Suda, T., Nagata, T., Aoshi, T., Uchijima, M., Yoshida, A., Chida, K., Koide, Y., Nakamura, H.
(2003). Induction of Protective Immunity to Listeria monocytogenes with Dendritic Cells Retrovirally Transduced with a Cytotoxic T Lymphocyte Epitope Minigene. Infect. Immun.
71: 1748-1754
[Abstract]
[Full Text]
-
Sashinami, H., Nakane, A., Iwakura, Y., Sasaki, M.
(2003). Effective Induction of Acquired Resistance to Listeria monocytogenes by Immunizing Mice with In Vivo-Infected Dendritic Cells. Infect. Immun.
71: 117-125
[Abstract]
[Full Text]
-
Shaw, J., Grund, V., Durling, L., Crane, D., Caldwell, H. D.
(2002). Dendritic Cells Pulsed with a Recombinant Chlamydial Major Outer Membrane Protein Antigen Elicit a CD4+ Type 2 Rather than Type 1 Immune Response That Is Not Protective. Infect. Immun.
70: 1097-1105
[Abstract]
[Full Text]
-
Belay, T., Eko, F. O., Ananaba, G. A., Bowers, S., Moore, T., Lyn, D., Igietseme, J. U.
(2002). Chemokine and Chemokine Receptor Dynamics during Genital Chlamydial Infection. Infect. Immun.
70: 844-850
[Abstract]
[Full Text]
-
Darville, T., Andrews, C. W. Jr., Sikes, J. D., Fraley, P. L., Braswell, L., Rank, R. G.
(2001). Mouse Strain-Dependent Chemokine Regulation of the Genital Tract T Helper Cell Type 1 Immune Response. Infect. Immun.
69: 7419-7424
[Abstract]
[Full Text]
Top
Abstract
Text
