Previous Article | Next Article 
Infection and Immunity, August 2000, p. 4752-4758, Vol. 68, No. 8
Department of Veterinary Pathobiology,
University of Minnesota, St. Paul, Minnesota 55108
Received 23 November 1999/Returned for modification 29 March
2000/Accepted 27 April 2000
Respiratory infection by Actinobacillus
pleuropneumoniae causes a highly pathogenic necrotizing
pleuropneumonia with severe edema, hemorrhage and fever. Acute
infection is characterized by expression of inflammatory cytokines,
including interleukin-1 (IL-1), IL-6 and IL-8. To determine if high
level production of inflammatory cytokines contributed to disease
pathogenesis, we investigated if inhibiting macrophage activation with
adenovirus type 5-expressed IL-10 (Ad-5/IL-10) reduced the severity of
acute disease. Porcine tracheal epithelial cells infected with
Ad-5/IL-10 produced bioactive human IL-10. When pigs were
intratracheally infected with A. pleuropneumoniae, pigs
pretreated with Ad-5/IL-10 showed a significant reduction in the amount
of lung damage when compared to adenovirus type 5-expressing
Overproduction of inflammatory
cytokines has been suggested to be a major factor in several diseases
that are associated with tissue damage. This is especially true in
various models of pulmonary disease, such as sepsis-induced lung injury
and acute respiratory distress syndrome (34, 35, 38). In
pigs, one such disease is pleuropneumonia caused by the gram-negative
bacterium Actinobacillus pleuropneumoniae (25).
This disease is characterized by high fever and respiratory distress,
with 10 to 30% of infected animals dying within 24 to 48 h and
the remainder obtaining a chronic persistent infection (10,
30). Lungs from pigs infected with A. pleuropneumoniae
show necrosis, fibrin, hemorrhagic lesions, and pleurisy (25, 27,
30). Lesioned areas of the lungs have high numbers of neutrophils
in the alveolar sacs (19, 20, 25). These neutrophils are
thought to be responsible for the lung damage associated with
pleuropneumonia (34).
In pigs experimentally challenged with A. pleuropneumoniae,
high levels of inflammatory cytokines are present in lung lavages. The
primary source of tumor necrosis factor (TNF), interleukin-1 (IL-1),
and IL-8 is the alveolar macrophage, which is the predominant immune
cell in the lung (4, 21, 29). IL-6 is produced in lung
tissue (4). IL-1 and IL-6 bioactivities in lung lavage fluid
samples of A. pleuropneumoniae-infected pigs are elevated 1,000-fold (4, 16). TNF alpha (TNF- IL-10 is an anti-inflammatory cytokine that is produced by T cells, B
cells, monocytes, and macrophages and which functions generally to
suppress immune and inflammatory reactions (26, 32). It not
only inhibits TNF- To test the hypothesis that macrophage activation, resulting in the
excessive production of inflammatory cytokines, exacerbates the
pathogenesis of bacterial lung infection, IL-10 was administered to the
lung via a recombinant, replication-deficient adenovirus which
expressed IL-10. The results showed that IL-10 expression in the lung
substantially reduced inflammatory cytokine expression and pathological
signs of bacterial pleuropneumonia.
Pigs.
Four- to six-week-old (8 to 10 kg) male pigs were
obtained from a pleuropneumonia-negative commercial herd. Animals were
anesthetized with telazole (10 mg/kg of body weight) (Fort Dodge
Laboratories, Fort Dodge, Iowa) and treatments were administered
intratracheally via the CO2 port of an ETCO2
tracheal tube (Sheridan Catheter Corp., Argyle, N.Y.) as previously
described (3).
0019-9567/00/$04.00+0
Copyright © 2000, American Society for Microbiology. All rights reserved.
Interleukin-10 Gene Therapy-Mediated
Amelioration of Bacterial Pneumonia
ABSTRACT
Top
Abstract
Introduction
Materials and Methods
Results
Discussion
References
-galactosidase (Ad-5/-Gal)-treated and untreated pigs. In
addition, serum zinc levels were unchanged, the lung weight/body weight
ratio (an indicator of vascular leakage) was significantly reduced, and
lung pathology scores were reduced. Myeloperoxidase activity in lung
lavage fluid samples, an indicator of neutrophil invasion, was
decreased to levels similar to that seen in pigs not infected with
A. pleuropneumoniae. Reduction in inflammatory cytokine
levels in lung lavage fluid samples correlated with the clinical
observations in that pigs pretreated with Ad-5/IL-10 showed a
corresponding reduction of IL-1 and tumor necrosis factor (TNF)
compared with untreated and Ad-5/-Gal-treated pigs. IL-6 levels were
unaffected by pretreatment with Ad-5/IL-10, consistent with
observations that IL-6 was not derived from alveolar macrophages. Since
inflammatory cytokines are expressed at high levels in acute bacterial
pleuropneumonia, these results indicate that macrophage activation,
involving overproduction of IL-1 and TNF, is a prime factor in
infection-related cases of massive lung injury.
INTRODUCTION
Top
Abstract
Introduction
Materials and Methods
Results
Discussion
References
) levels also may be profoundly elevated but show greater variation (4, 16).
Because TNF and IL-1 induce vascular permeability, injure endothelial cells, and cause death in sepsis-induced lung injury (11,
34), we hypothesize that the overproduction of inflammatory
cytokines plays a key role in the lung damage associated with pleuropneumonia.
and IL-1 expression directly in alveolar
macrophages but also up-regulates other anti-inflammatory cytokines,
including IL-1Ra from fibroblasts and sTNF-RI (12, 13, 36).
The anti-inflammatory and immunoregulatory properties of IL-10 are
consistent with a therapeutic role for IL-10 in diseases characterized
by exuberant production of inflammatory cytokines (17).
MATERIALS AND METHODS
Top
Abstract
Introduction
Materials and Methods
Results
Discussion
References
-galactosidase
[Ad-5/-Gal]) or the human IL-10 gene (Ad-5/IL-10) per pig. Pigs
were monitored for clinical signs daily for 6 days. On the sixth day, 5 ml of 5% BSA in PBS (control pigs) or 5 ml of 5% BSA in PBS
containing 104 CFU of A. pleuropneumoniae was
instilled intratracheally. Twenty-four hours after instillation of the
bacteria, pigs were sacrificed. Euthanasia was performed with
Beuthanasia-D Special (Schering-Plough Animal Health, Kenilworth,
N.J.). Treatment groups were housed in separate isolation rooms
throughout the experiment. All animal protocols were approved by the
Institutional Animal Care and Use Committee, University of Minnesota.
TABLE 1.
Effect of IL-10 treatment on serum zinc levels in pigs
infected with A. pleuropneumoniae
Adenoviruses, A. pleuropneumoniae inoculation, and
cell culture.
Nonreplicating Ad-5/-Gal and Ad-5/IL-10 driven by
the Rous sarcoma virus early promoter were supplied by Beverly Davidson (Vector Core Laboratory, University of Iowa, Iowa City). Virus titers
were determined with a limiting-dilution assay on 293 cells (23). Porcine tracheal epithelial (PTE) cells were supplied by Lance Bouen (University of Minnesota, St. Paul, Minn.) and were
maintained in Dulbecco's modified Eagle medium (DMEM) containing 10%
fetal bovine serum (FBS).
-NAD. Bacteria were grown overnight at 37°C in
5% CO2. A single colony was picked and used to inoculate 3% tryptic soy broth containing 1% NZ amine, 0.1% yeast extract, and
0.001% -NAD. Log-phase growing bacteria were washed one time with
PBS and resuspended in PBS containing 5% BSA. Animals received 5 × 104 CFU in a volume of 5 ml per inoculation. Bacterial
plate counts were performed immediately after instillation to verify
the number of viable bacteria.
PTE cells were treated with Ad-5/IL-10 at a multiplicity of infection
of 10:1 in six-well plates (1.5 × 105 cells/well) in
a total volume of 0.5 ml DMEM-10% FBS for 2 h at 37°C. Control
wells were treated with medium only. After 2 h, the cells were
washed three times with DMEM-10% FBS and overlaid with 1 ml of
DMEM-10% FBS. Day 0 samples were removed immediately after addition
of medium (day 0) and at daily intervals up to 10 days postinfection.
After removal, the medium was frozen in dry ice-ethanol and stored at
70°C. RNA was processed immediately after removal of the medium
(see below).
Clinical and gross pathology. Pigs were observed for signs of sickness throughout the experiment. Signs included diarrhea, coughing, nasal discharge, respiratory distress, clinical depression, inappetence, and inactivity.
Percent lung weight/body weight ratio (%L/B) was determined from heart and lung plucks. Lungs were scored using a method described by Bertram (4, 6). Lung pathology scores were confirmed by two different individuals according to the following scale: 0, no lesions; 1, not more than two lesions, each less than 15 mm in diameter; 2, not more than two lesions, each less than 50 mm in diameter, or a few scattered loci; 3, two or more lesions greater than 50 mm in diameter or numerous scattered loci but not involving more that one-third of the lung; 4, more lesions or lung involvement than described for 0 to 3. Serum zinc level determinations and A. pleuropneumoniae reisolation from lung tissue were performed by the Minnesota Diagnostic Laboratory.RNA isolation, semiquantitative reverse transcription (RT)-PCR, and Northern blotting. RNA was isolated from cultured cells (9 × 106 cells) using Trizol (Gibco BRL) and from 108 lung lavage macrophages or 0.5 g of lung tissue using acid-guanidinium extraction (9). RNA was quantitated by UV spectroscopy at 260 nm.
Semiquantitative RT-PCR was performed using 1 µg of RNA. The RNA was reverse-transcribed using a 1 mM concentration of each deoxynucleoside triphosphate, 5 mM MgCl2, and Superscript reverse transcriptase (2.5 U/µl; Life Technologies). Incubations were at 25°C for 10 min, 42°C for 15 min, 99°C for 5 min, and 5°C for 5 min. Control reactions to check for DNA contamination were run without reverse transcriptase. PCRs were performed with 2.5 µl of the cDNA products in a final volume of 25 µl with an annealing temperature of 55°C (30 s), an elongation temperature of 72°C (45 s), and a melting temperature of 93°C (45 s) for 30 cycles (-actin) or 35 cycles (IL-10).
Amplification from mRNA and not DNA was achieved by using primers which
spanned introns in genomic DNA. Reaction products were electrophoresed in 1.5% agarose gels and quantitated using NIH Image software. Relative IL-10 levels were determined after normalization to -actin.
For Northern blotting, RNA (20 µg/lane) was electrophoresed in a 1%
agarose-2.2 M formaldehyde gel and transferred onto a nylon membrane
in 20× SSC (1× SSC is 0.15 M NaCl plus 0.015 M sodium citrate).
Probes were produced with the Prime-It II kit (Stratagene) and 25 ng of
the appropriate cDNA insert as a template and purified using the Qiagen
nucleotide removal kit. Overnight hybridizations were performed in
Quik-Hyb (Stratagene) at 68°C. The membranes were washed once with
2× SSC containing 1% sodium dodecyl sulfate at room temperature and
then with 0.2× SSC containing 1% sodium dodecyl sulfate at 42°C.
Membranes were quantified by phosphorimaging (Molecular Dynamics,
Sunnyvale, Calif.).
Cytokine quantitation.
IL-10 was quantitated using an
enzyme-linked immunosorbent assay (ELISA) (Biosource International)
which recognized human IL-10 (hIL-10) but not porcine IL-10
(unpublished observation). TNF- levels were determined by ELISA
specific for porcine TNF- (Endogen). IL-6 was quantitated using a
B-9 cell bioassay (1), and IL-1 was quantitated using a
D-10S cell (American Type Culture Collection) bioassay (15).
IL-1Ra was quantitated using a hIL-1Ra ELISA (R & D Systems).
IL-10 bioactivity.
IL-10 activity was determined by
measuring inhibition of lipopolysaccharide (LPS)-induced TNF-
expression from porcine alveolar lavage fluid sample cells. Lavage
fluid sample cells were plated at a density of 2 × 105 cells/well in a 96-well plate, washed, and incubated
overnight at 37°C. The medium was removed and 100 µl of fresh
medium containing recombinant hIL-10 (R & D Systems) or medium from
untreated or Ad-5/IL-10-treated PTE cells was added to each well. Cells
were incubated for 1 h, and then LPS was added to a final
concentration of 0.16 µg/ml for 6 h at 37°C. TNF in the medium
was quantitated by ELISA.
MPO activity. Neutrophils were quantified by myeloperoxidase (MPO) activity (8). Briefly, 50 µl of lung lavage fluid diluted in PBS was placed in wells of a 96-well plate and enzymatic activity was determined with tetramethylbenzidine and H2O2 (Kirkegaard & Perry Laboratories, Inc.).
Statistical analysis. Group differences were analyzed for significance by unpaired t tests or the Mann-Whitney test (see Fig. 5A) using Prism software (GraphPad Software, San Diego, Calif.).
| |
RESULTS |
|---|
|
Top
Abstract
Introduction
Materials and Methods
Results
Discussion
References
|
|---|
In vitro expression of IL-10.
PTE cells infected with
Ad-5/IL-10 showed no difference in gross morphology from normal
untreated cells during 10 days of incubation. Untreated PTE cells
secreted no detectable IL-10 over a 10-day time course, while those
treated with Ad-5/IL-10 secreted IL-10 throughout, reaching a final
concentration of 390 ± 75 pg/ml (Fig.
1A). RNA isolated from these cells was
also analyzed by semiquantitative RT-PCR to determine the time course
of IL-10 mRNA expression (Fig. 1B). IL-10 mRNA was detectable at low
levels 2 h after treatment with Ad-5/IL-10 and peaked at 8 days.
|
from porcine alveolar macrophages. Pretreatment of alveolar macrophages with IL-10 at concentrations from 10 pg/ml to 10 ng/ml inhibited TNF- secretion in a dose-dependent manner (Fig.
2A). Culture supernatants from
Ad-5/IL-10-treated PTE cells, but not untreated ones, also inhibited
LPS-induced TNF- secretion by porcine alveolar macrophages (Fig.
2B).
|
In vivo expression of Ad-5/-Gal and Ad-5/IL-10.
The
distribution of Ad-5-delivered proteins in the lungs of pigs following
intratracheal administration was determined by immunohistochemical
labeling of -Gal in lung tissue isolated from pigs treated with
1010 PFU of Ad-5/-Gal (Fig.
3). -Gal labeling was detected in lung tissue sections taken from the caudal and middle lobes of the right
lung and caudal lobe of the left lung but not from the cranial lobe of
either lung. Labeling was evident in the epithelial cells of the
alveoli and bronchioles (Fig. 3). No labeling was seen in tissue
sections incubated with nonimmune antisera (Fig. 3B and D). The
production of IL-10 in the lungs of Ad-5/IL-10-treated pigs was
confirmed by ELISA. Lung lavage fluid from animals pretreated with
Ad-5/IL-10 and challenged with A. pleuropneumoniae contained significant levels of IL-10, while that from Ad-5/-Gal-treated or
nontreated animals did not (Fig. 4).
|
|
Alteration of A. pleuropneumoniae pathogenesis by
Ad-5/IL-10: clinical observations, lung pathology, and serum zinc
levels.
In order to determine if IL-10 delivered to the lung by
Ad-5 prior to infection with A. pleuropneumoniae would
ameliorate the resulting disease, we pretreated pigs with either
Ad-5/IL-10, Ad-5/-Gal, or vehicle. After 6 days, half of each group
was challenged with A. pleuropneumoniae. All pigs appeared
generally healthy prior to and after Ad-5 treatment up to the time of
A. pleuropneumoniae instillation. Twenty-four hours after
challenge, pigs pretreated with vehicle or pretreated with Ad-5/-Gal
exhibited nasal discharge, labored breathing, depression, and
listlessness. In marked contrast, A. pleuropneumoniae-infected pigs pretreated with Ad-5/IL-10 showed no clinical signs of disease. A. pleuropneumoniae was
reisolated from the lungs of all pigs that were inoculated, including
those pretreated with Ad-5/IL-10 which did not show clinical signs. A. pleuropneumoniae was not isolated from any of the animals
pretreated with vehicle.
-Gal had extensive fibrin deposits on the
visceral and parietal pleura and extensive consolidation, edema, and
hemorrhage of the lungs. A. pleuropneumoniae-infected pigs
pretreated with Ad-5/IL-10 had no fibrin deposits, and lung lesions
were far less severe than those in the lungs from the other A. pleuropneumoniae-infected pigs. Pretreatment with Ad-5/IL-10
significantly reduced the median lung score from 4 (with a range of 3 to 4) to 2 (with a range of 1 to 2) (P = 0.018) (Fig.
5A).
|
-Gal averaged 3.7 ± 0.89% of body
weight, compared to 2.5 ± 0.26% for non-A.
pleuropneumoniae-infected pigs (P = 0.02) (Fig.
5B). Pretreatment with Ad-5/IL-10 tended to reduce the effect of
A. pleuropneumoniae on lung weight (2.8 ± 0.38%; P = 0.055).
Neutrophil invasion.
The influx of neutrophils, a common
response to bacterial infection, was substantial in pigs infected with
A. pleuropneumoniae without exposure to adenovirus or
treated with Ad-5/-Gal. MPO activity, a measure of neutrophilia
(8), was approximately 8.5-fold higher in infected pigs than
in noninfected pigs (Fig. 5C) (P = 0.003). By contrast,
pretreatment with Ad-5/IL-10 completely suppressed neutrophil influx,
since MPO activity was the same as that in noninfected pigs (Fig. 5C).
Serum zinc levels.
Zinc levels in serum taken prior to and
immediately before the introduction of A. pleuropneumoniae
in virus-treated pigs (groups 3 to 6) were comparable to that seen in
pigs receiving no virus; approximately 1 ppm (Table 1). Twenty-four
hours following A. pleuropneumoniae instillation, serum zinc
levels in pigs pretreated with vehicle (groups 1 and 2) dropped
significantly from 1.01 ± 0.01 ppm in pigs not infected with
A. pleuropneumoniae (group 1) to 0.66 ± 0.08 ppm in
A. pleuropneumoniae-infected pigs (group 2) (P = 0.027). Similarly, pigs pretreated with Ad-5/-Gal (groups 3 and
4) exhibited a significant drop in serum zinc from 0.93 ± 0.05 ppm in pigs not infected with A. pleuropneumoniae to
0.65 ± 0.12 ppm in A. pleuropneumoniae-infected pigs
(P = 0.013). However, in pigs pretreated with
Ad-5/IL-10 (groups 5 and 6) serum zinc did not decrease significantly
when infected with A. pleuropneumoniae (0.92 ± 0.07 ppm in pigs not infected with A. pleuropneumoniae to
0.81 ± 0.17 ppm in A. pleuropneumoniae-infected pigs;
P = 0.180).
Alteration of A. pleuropneumoniae pathogenesis by
Ad-5/IL-10: effects on lung cytokines.
IL-1, TNF-, and IL-6
levels were examined in lung lavage fluid samples to correlate the
clinical results with cytokine production (Fig.
6). Both IL-1 and TNF- were elevated
upon infection with A. pleuropneumoniae in pigs pretreated
with vehicle or pretreated with Ad-5/-Gal. IL-1 levels were 88 ± 57 pg/ml in pigs not infected with A. pleuropneumoniae
and 702 ± 47 pg/ml in A. pleuropneumoniae-infected pigs (Fig. 6A). Similarly, TNF- levels were 1.3 ± 1.3 and
73 ± 8.2 pg/ml in noninfected and A. pleuropneumoniae-infected pigs, respectively (Fig. 6B). In
contrast, pretreatment of infected pigs with Ad-5/IL-10 resulted in
levels of IL-1 and TNF- that were the same as in pigs not infected
with A. pleuropneumoniae (85 ± 25 pg/ml versus 60 ± 83 pg/ml for IL-1 and 3.2 ± 0.1 pg/ml versus 3.2 ± 1.9 pg/ml for TNF-, respectively). In contrast to IL-1 and TNF-,
IL-6 levels were not significantly altered by Ad-5/IL-10 pretreatment
(Fig. 6C).
|
| |
DISCUSSION |
|---|
|
Top
Abstract
Introduction
Materials and Methods
Results
Discussion
References
|
|---|
Excessive inflammatory reactions triggered by expression of proinflammatory cytokines contribute to the severity of bacterial infections of the lung, which may result in life-threatening disease (4, 5, 7, 41). Marked elevations of IL-1, IL-6, and TNF occurred acutely after A. pleuropneumoniae infection in swine and were coincident with the onset of clinical disease (4, 16). Similarly, murine models of bacterial pneumonia indicate that proinflammatory cytokine expression is amplified acutely following infection and that overexpression of TNF exacerbates disease (22, 33). While high levels of inflammatory cytokines are associated with increased disease severity, moderate levels of these cytokines, especially TNF, are implicated in effective control of lung infection. Endogenous TNF appears to be required for murine defense to acute Klebsiella pneumoniae infection, whereas high levels of expression were not beneficial (18, 33).
In order to determine if excessive proinflammatory cytokine production exacerbates the pathogenesis of bacterial lung infection in pigs, we used in vivo gene therapy with recombinant Ad-5/IL-10 to suppress the production of cytokines in macrophages. IL-10 inhibits TNF and IL-1 production in macrophages and monocytes and also up-regulates other anti-inflammatory cytokines, including sTNF-R1 and IL-1Ra from fibroblasts (2, 12, 13, 36). hIL-10 was also demonstrated to attenuate TNF expression in porcine monocytes (14).
Pretreatment of pigs by instillation of Ad-5/IL-10 into the lungs
reduced the severity of pleuropneumonia. Lung damage (lung pathology
scores), lung edema (%L/B), acute phase response (serum zinc), and
neutrophil influx (MPO) were all significantly reduced. The
amelioration of disease severity was associated with reduced expression
of IL-1 and TNF in pigs treated with Ad-5/IL-10 but not with
Ad-5/-Gal. We showed that IL-10 blocks the expression of
inflammatory cytokines in macrophages induced by LPS, that Ad-5/IL-10
infects porcine endothelial cells, and that Ad-5/IL-10 expresses
biologically active protein.
The inhibition of LPS-stimulated TNF- expression from porcine
alveolar macrophages by IL-10 showed dose dependence similar to that
observed in human and mouse cells. Recombinant hIL-10 has a 50%
effective dose (ED50) of 0.5 to 1.0 ng/ml using a murine mast cell proliferation assay (37). Similarly, hIL-10
inhibits LPS-stimulated TNF- expression in human macrophages by 40%
(36) and in synovial fluid macrophages and monocytes by 75%
(12, 13) at a concentration of 10 ng/ml. hIL-10 also
inhibited porcine TNF- expression by 70% at a concentration of 10 ng/ml with an ED50 of ~1.2 ng/ml.
The lack of effect of Ad-5/IL-10 on IL-6 expression in lungs of swine acutely infected with A. pleuropneumoniae was consistent with previous observations that IL-6 is not produced to a significant degree by macrophages in lung (4). IL-10 also does not suppress LPS-induced expression of IL-6 by human alveolar macrophages (42). Thus, it appears that IL-10 reduces the severity of acute pneumonia by preventing activation of macrophages, the expression of proinflammatory cytokines, and the recruitment of neutrophils.
The effect of IL-10 treatment on outcome of bacterial pneumonia in mice may be similar to or different from the protective effect in pigs. Systemic IL-10 decreased lung injury in mice given cytotoxic strains of Pseudomonas aeruginosa, an effect which required the presence of gamma interferon (28). Local expression of IL-10 in lung also improved survival against K. pneumoniae infection, enhanced lung clearance, and reduced dissemination (33). By contrast, IL-10 impaired the murine host defense against streptococcal pneumonia, including attenuation of proinflammatory cytokine expression (39). The variability in effect of IL-10 on disease severity and outcome is likely dependent on the pathogen. For example, A. pleuropneumoniae in our experimental model induces an extremely acute pleuropneumonia, whereas P. aeruginosa in mice is a model of chronic infection. Since resolution of infection requires a balance between proinflammatory and anti-inflammatory responses, differences in the model organism and its interaction with the host might affect treatment outcomes (22). IL-10 also may have somewhat different functions in swine and mice similar to other differences in innate immune responses to acute bacterial infection. Pigs readily express the principal neutrophil chemoattractant, IL-8, in alveolar macrophages and in the lungs (4, 16, 21), whereas mice lack the IL-8 gene. Swine do not express inducible nitric oxidase synthase activity in the lung, whereas inducible nitric oxidase synthase is an important innate immune component in mice (24).
The presence of adenovirus alone did not adversely affect lung pathology or induce an inflammatory response. The dose of virus was in the range which caused little or no response in baboons or humans (31, 40). Our results show that immunologic manipulation of cytokine expression can be an important adjunct therapy in the treatment of serious lung infections. The anti-inflammatory and immunoregulatory properties of IL-10 are consistent with a therapeutic role in diseases characterized by exuberant production of inflammatory cytokines, including bacterial infections and autoimmune inflammatory diseases (17).
| |
ACKNOWLEDGMENTS |
|---|
This work was supported by United States Department of Agriculture grant 96-35204-3389 (M.P.M.).
We thank Beverly Davidson for providing Ad-5/IL-10 and Ad-5/-Gal
viral stocks.
| |
FOOTNOTES |
|---|
* Corresponding author. Mailing address: Department of Veterinary Pathobiology, University of Minnesota, 205 VSB, 1971 Commonwealth Ave., St Paul, MN 55108. Phone: (612) 625-6735. Fax: (612) 625-5203. E-mail: murta001{at}tc.umn.edu.
Editor: R. N. Moore
| |
REFERENCES |
|---|
|
Top
Abstract
Introduction
Materials and Methods
Results
Discussion
References
|
|---|
| 1. | Aarden, L. A., E. R. De Groot, O. L. Schaap, and P. M. Lansdorp. 1987. Production of hybridoma growth factor by human monocytes. Eur. J. Immunol. 17:1411-1416[Medline]. |
| 2. |
Armstrong, L.,
N. Jordan, and A. Millar.
1996.
Interleukin 10 (IL-10) regulation of tumour necrosis factor alpha (TNF-alpha) from human alveolar macrophages and peripheral blood monocytes.
Thorax
51:143-149 |
| 3. | Baarsch, M. J., D. L. Foss, and M. P. Murtaugh. Pathophysiological correlates of acute porcine pleuropneumonia. Am. J. Vet. Res., in press. |
| 4. | Baarsch, M. J., R. W. Scamurra, K. Burger, D. L. Foss, S. K. Maheswaran, and M. P. Murtaugh. 1995. Inflammatory cytokine expression in swine experimentally infected with Actinobacillus pleuropneumoniae. Infect. Immun. 63:3587-3594[Abstract]. |
| 5. |
Bergeron, Y.,
N. Ouellet,
A. M. Deslauriers,
M. Simard,
M. Olivier, and M. G. Bergeron.
1998.
Reduction by cefodizime of the pulmonary inflammatory response induced by heat-killed Streptococcus pneumoniae in mice.
Antimicrob. Agents Chemother.
42:2527-2533 |
| 6. | Bertram, T. A. 1985. Quantitative morphology of peracute pulmonary lesions in swine induced by Haemophilus pleuropneumoniae. Vet. Pathol. 22:598-609[Abstract]. |
| 7. | Braciak, T. A., S. K. Mittal, F. L. Graham, C. D. Richards, and J. Gauldie. 1993. Construction of recombinant human type 5 adenoviruses expressing rodent IL-6 genes. An approach to investigate in vivo cytokine function. J. Immunol. 151:5145-5153[Abstract]. |
| 8. | Bradley, P. P., D. A. Priebat, R. D. Christensen, and G. Rothstein. 1982. Measurement of cutaneous inflammation: estimation of neutrophil content with an enzyme marker. J. Investig. Dermatol. 78:206-209[CrossRef][Medline]. |
| 9. | Chomczynski, P., and N. Sacchi. 1987. Single-step method of RNA isolation by acid guanidinium thiocyanate-phenol-chloroform extraction. Anal. Biochem. 162:156-159[Medline]. |
| 10. | Desrosiers, R. 1986. Therapeutic control and economic aspect of porcine pleuropneumonia in finishing units. Vet. Rec. 119:89-90[Medline]. |
| 11. |
Goldblum, S. E.,
B. Hennig,
M. Jay,
K. Yoneda, and C. J. McClain.
1989.
Tumor necrosis factor alpha-induced pulmonary vascular endothelial injury.
Infect. Immun.
57:1218-1226 |
| 12. | Hart, P. H., M. J. Ahern, M. D. Smith, and J. J. Finlay-Jones. 1995. Comparison of the suppressive effects of interleukin-10 and interleukin-4 on synovial fluid macrophages and blood monocytes from patients with inflammatory arthritis. Immunology 84:536-542[Medline]. |
| 13. | Hart, P. H., C. A. Jones, and J. J. Finlay-Jones. 1995. Monocytes cultured in cytokine-defined environments differ from freshly isolated monocytes in their responses to IL-4 and IL-10. J. Leukoc. Biol. 57:909-918[Abstract]. |
| 14. |
Hofstetter, C.,
M. Kleen,
O. Habler,
A. M. Allmeling,
F. Krombach, and B. Zwissler.
1998.
Recombinant human interleukin-10 attenuates TNF production by porcine monocytes.
Eur. J. Med. Res.
3:299-303[Medline].
|
| 15. | Hopkins, S. J., and M. Humphreys. 1989. Simple, sensitive and specific bioassay of interleukin-1. J. Immunol. Methods 120:271-276[CrossRef][Medline]. |
| 16. | Huang, H., A. A. Potter, M. Campos, F. A. Leighton, P. J. Willson, D. M. Haines, and W. D. Yates. 1999. Pathogenesis of porcine Actinobacillus pleuropneumonia, part II: roles of proinflammatory cytokines. Can. J. Vet. Res. 63:69-78[Medline]. |
| 17. | Keystone, E. C., J. C. Wherry, and P. Grint. 1998. IL-10 as a therapeutic strategy in the treatment of rheumatoid arthritus. Rheum. Dis. Clin. N. Am. 24:629-639[CrossRef][Medline]. |
| 18. | Laichalk, L. L., S. L. Kunkel, R. M. Strieter, J. M. Danforth, M. B. Bailie, and T. J. Standiford. 1996. Tumor necrosis factor mediates lung antibacterial host defense in murine Klebsiella pneumonia. Infect. Immun. 64:5211-5218[Abstract]. |
| 19. | Liggett, A. D., L. R. Harrison, and R. L. Farrell. 1986. Acute inflammatory effects of intratracheally instilled Escherichia coli endotoxin and sonicated suspension of Haemophilus pleuropneumoniae in swine. Can. J. Vet. Res. 50:526-531[Medline]. |
| 20. | Liggett, A. D., L. R. Harrison, and R. L. Farrell. 1987. Sequential study of lesion development in experimental Haemophilus pleuropneumonia. Res. Vet. Sci. 42:204-212[Medline]. |
| 21. |
Lin, G.,
A. E. Pearson,
R. W. Scamurra,
Y. Zhou,
M. J. Baarsch,
D. J. Weiss, and M. P. Murtaugh.
1994.
Regulation of interleukin-8 expression in porcine alveolar macrophages by bacterial lipopolysaccharide.
J. Biol. Chem.
269:77-85 |
| 22. | Moore, T. A., and T. J. Standiford. 1998. The role of cytokines in bacterial pneumonia: an inflammatory balancing act. Proc. Assoc. Am. Phys. 110:297-305[Medline]. |
| 23. | O'Reilly, D. R., L. K. Miller, and V. A. Luckow. 1992. Baculovirus expression vectors: a laboratory manual. W. H. Freeman and Co., New York, N.Y. |
| 24. | Pampusch, M. S., A. M. Bennaars, S. Harsch, and M. P. Murtaugh. 1998. Inducible nitric oxide synthase expression in porcine immune cells. Vet. Immunol. Immunopathol. 61:279-289[CrossRef][Medline]. |
| 25. | Pattison, I. H., D. G. Howell, and J. Elliot. 1957. A haemophilus-like organism isolated from pig lung and the associated pneumonic lesion. J. Comp. Pathol. 67:320-324[Medline]. |
| 26. |
Rennick, D. M.,
M. M. Fort, and N. J. Davidson.
1997.
Studies with IL-10 / mice: an overview.
J. Leukoc. Biol.
61:389-396[Abstract].
|
| 27. | Rosendal, S., O. P. Miniats, and P. Sinclair. 1986. Protective efficacy of capsule extracts of Haemophilus pleuropneumoniae in pigs and mice. Vet. Microbiol. 12:229-240[CrossRef][Medline]. |
| 28. | Sawa, T., D. B. Corry, M. A. Gropper, M. Ohara, K. Kurahashi, K. Wiener, and J. P. Kronish. 1997. IL-10 improves lung injury and survival in Pseudomonas aeruginosa pneumonia. J. Immunol. 159:2858-2866[Abstract]. |
| 29. | Scamurra, R. W., C. Arriaga, L. Sprunger, M. J. Baarsch, and M. P. Murtaugh. 1996. Regulation of interleukin-6 expression in porcine immune cells. J. Interferon Cytokine Res. 16:289-296[Medline]. |
| 30. | Sebunya, T. N., and J. R. Saunders. 1983. Haemophilus pleuropneumoniae infection in swine: a review. J. Am. Vet. Med. Assoc. 182:1331-1337[Medline]. |
| 31. | Simon, R. H., J. F. Engelhardt, Y. Yang, M. Zepeda, S. Weber-Pendleton, M. Grossman, and J. M. Wilson. 1993. Adenovirus-mediated transfer of the CFTR gene to lung of nonhuman primates: toxicity study. Hum. Gene Ther. 4:771-780[Medline]. |
| 32. | Spits, H., and R. de Waal Malefyt. 1992. Functional characterization of human IL-10. Int. Arch. Allergy Immunol. 99:8-15[Medline]. |
| 33. | Standiford, T. J., J. M. Wilkowski, T. H. Sisson, N. Hattori, B. Mehrad, K. A. Bucknell, and T. A. Moore. 1999. Intrapulmonary tumor necrosis factor gene therapy increases bacterial clearance and survival in murine gram-negative pneumonia. Hum. Gene Ther. 10:899-909[CrossRef][Medline]. |
| 34. | Stephens, K. E., A. Ishizaka, Z. H. Wu, J. W. Larrick, and T. A. Raffin. 1988. Granulocyte depletion prevents tumor necrosis factor-mediated acute lung injury in guinea pigs. Am. Rev. Respir. Dis. 138:1300-1307[Medline]. |
| 35. | Suter, P. M., S. Suter, E. Girardin, P. Roux-Lombard, G. E. Grau, and J. M. Dayer. 1992. High bronchoalveolar levels of tumor necrosis factor and its inhibitors, interleukin-1, interferon, and elastase, in patients with adult respiratory distress syndrome after trauma, shock, or sepsis. Am. Rev. Respir. Dis. 145:1016-1022[Medline]. |
| 36. | Thomassen, M. J., L. T. Divis, and C. J. Fisher. 1996. Regulation of human alveolar macrophage inflammatory cytokine production by interleukin-10. Clin. Immunol. Immunopathol. 80:321-324[CrossRef][Medline]. |
| 37. |
Thompson-Snipes, L.,
V. Dhar,
M. W. Bond,
T. R. Mosmann,
K. W. Moore, and D. M. Rennick.
1991.
Interleukin 10: a novel stimulatory factor for mast cells and their progenitors.
J. Exp. Med.
173:507-510 |
| 38. | Tran, V. N., B. Misset, F. Lebargy, J. Carlet, and J. F. Bernaudin. 1993. Expression of tumor necrosis factor-alpha gene in alveolar macrophages from patients with the adult respiratory distress syndrome. Am. Rev. Respir. Dis. 147:1585-1589[Medline]. |
| 39. | Van der Poll, T., A. Marchant, C. V. Keogh, M. Goldman, and S. F. Lowry. 1996. Interleukin-10 impairs host defense in murine pneumococcal pneumonia. J. Infect. Dis. 174:994-1000[Medline]. |
| 40. | Wilson, J. M., J. F. Engelhardt, M. Grossman, R. H. Simon, and Y. Yang. 1994. Gene therapy of cystic fibrosis lung disease using E1 deleted adenoviruses: a phase I trial. Hum. Gene Ther. 5:501-519[Medline]. |
| 41. | Xing, Z., T. Braciak, M. Jordana, K. Croitoru, F. L. Graham, and J. Gauldie. 1994. Adenovirus-mediated cytokine gene transfer at tissue sites. Overexpression of IL-6 induces lymphocytic hyperplasia in the lung. J. Immunol. 153:4059-4069[Abstract]. |
| 42. | Zissel, G., J. Schlaak, M. Schlaak, and J. Muller-Quernheim. 1996. Regulation of cytokine release by alveolar macrophages treated with interleukin-4, interleukin-10, or transforming growth factor beta. Eur. Cytokine Netw. 7:59-66[Medline]. |
Infection and Immunity, August 2000, p. 4752-4758, Vol. 68, No. 8
0019-9567/00/$04.00+0
Copyright © 2000, American Society for Microbiology. All rights reserved.
This article has been cited by other articles:
-
Azevedo, M. S. P., Yuan, L., Pouly, S., Gonzales, A. M., Jeong, K. I., Nguyen, T. V., Saif, L. J.
(2006). Cytokine Responses in Gnotobiotic Pigs after Infection with Virulent or Attenuated Human Rotavirus. J. Virol.
80: 372-382
[Abstract] [Full Text] -
Franco-Penteado, C. F., De Souza, I. A., Camargo, E. A., Teixeira, S. A., Muscara, M. N., De Nucci, G., Antunes, E.
(2005). Mechanisms Involved in the Enhancement of Allergic Airways Neutrophil Influx by Permanent C-Fiber Degeneration in Rats. J. Pharmacol. Exp. Ther.
313: 440-448
[Abstract] [Full Text] -
Dumasius, V., Mendez, M., Mutlu, G. M., Factor, P.
(2002). Acute Lung Injury Does Not Impair Adenoviral-Mediated Gene Transfer to the Alveolar Epithelium. Chest
121: 33S-34S
[Abstract] [Full Text] -
FACTOR, P., MENDEZ, M., MUTLU, G. M., DUMASIUS, V.
(2002). Acute Hyperoxic Lung Injury Does Not Impede Adenoviral-mediated Alveolar Gene Transfer. Am. J. Respir. Crit. Care Med.
165: 521-526
[Abstract] [Full Text]
| |||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||
Copyright © 2009 by the American Society for Microbiology. For an alternate route to Journals.ASM.org, visit: http://intl-journals.asm.org | More Info»