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1.
Int J Mol Sci ; 22(20)2021 Oct 09.
Article in English | MEDLINE | ID: mdl-34681561

ABSTRACT

Chagas disease is a human infectious disease caused by Trypanosoma cruzi and can be transmitted by triatomine vectors, such as Rhodnius prolixus. One limiting factor for T. cruzi development is the composition of the bacterial gut microbiota in the triatomine. Herein, we analyzed the humoral immune responses of R. prolixus nymphs treated with antibiotics and subsequently recolonized with either Serratia marcescens or Rhodococcus rhodnii. The treatment with antibiotics reduced the bacterial load in the digestive tract, and the recolonization with each bacterium was successfully detected seven days after treatment. The antibiotic-treated insects, recolonized with S. marcescens, presented reduced antibacterial activity against Staphylococcus aureus and phenoloxidase activity in hemolymph, and lower nitric oxide synthase (NOS) and higher defensin C gene (DefC) gene expression in the fat body. These insects also presented a higher expression of DefC, lower prolixicin (Prol), and lower NOS levels in the anterior midgut. However, the antibiotic-treated insects recolonized with R. rhodnii had increased antibacterial activity against Escherichia coli and lower activity against S. aureus, higher phenoloxidase activity in hemolymph, and lower NOS expression in the fat body. In the anterior midgut, these insects presented higher NOS, defensin A (DefA) and DefC expression, and lower Prol expression. The R. prolixus immune modulation by these two bacteria was observed not only in the midgut, but also systemically in the fat body, and may be crucial for the development and transmission of the parasites Trypanosoma cruzi and Trypanosoma rangeli.


Subject(s)
Anti-Bacterial Agents/therapeutic use , Rhodnius/microbiology , Rhodococcus/immunology , Serratia marcescens/immunology , Animals , Anti-Bacterial Agents/pharmacology , Defensins/metabolism , Fat Body/metabolism , Gastrointestinal Microbiome/drug effects , Gene Expression Regulation/drug effects , Immunity, Humoral , Insect Proteins/metabolism , Monophenol Monooxygenase/metabolism , Nitric Oxide Synthase/metabolism , Rhodnius/drug effects , Rhodnius/immunology , Rhodnius/metabolism , Staphylococcus aureus/physiology
2.
Comp Immunol Microbiol Infect Dis ; 73: 101540, 2020 Dec.
Article in English | MEDLINE | ID: mdl-32911379

ABSTRACT

Rhodococcus equi causes suppurative pneumonia in foals aged 1-3 months; moreover, it has emerged as a pathogenic cause of zoonotic diseases. After the initial report of the ruminant-pathogenic factor VapN encoded by the novel virulence plasmid pVAPN, several reports have described ruminant infections caused by vapN-harboring R. equi. Herein, we conducted a serological epidemiological surveillance in goats at a breeding farm (Farm A) and characterized the vapN-harboring R. equi isolates from this farm. First, we established a simple screening enzyme-linked immunosorbent assay (ELISA) using recombinant glutathione S-transferase-tagged VapN as an immobilized antigen. This method revealed that the VapN antibody titers were elevated in 12 of 42 goats. Subsequently, we attempted to isolate R. equi from the goat feces and soil of Farm A. choE+/vapN+R. equi was isolated from the feces of Goat No. 27 and a soil sample near the shed. The pulsed-field gel electrophoresis (PFGE) patterns of five vapN-harboring R. equi strains isolated from Farm A in 2013 and 2019 were investigated and found to be the same except for the strain (OKI2019F1). However, no difference was observed in VapN expression and growth in macrophages among these vapN-harboring R. equi isolates. Our results revealed that some goats had histories of vapN-harboring R. equi infections, and two genomic types of vapN-harboring R. equi were found in isolates from Farm A. Ruminant-specific (pVAPN-carrying) R. equi might be an unrecognized pathogen in Japan and further studies are required to determine its prevalence and distribution.


Subject(s)
Actinomycetales Infections/veterinary , Goat Diseases/epidemiology , Rhodococcus equi/immunology , Rhodococcus/immunology , Actinomycetales Infections/epidemiology , Animals , Antibodies, Bacterial/blood , Cattle , Cattle Diseases/microbiology , Female , Goat Diseases/microbiology , Goats , Japan , Rhodococcus equi/genetics
3.
N Biotechnol ; 32(6): 559-68, 2015 Dec 25.
Article in English | MEDLINE | ID: mdl-25796474

ABSTRACT

Actinobacteria of the genus Rhodococcus produce trehalolipid biosurfactants with versatile biochemical properties and low toxicity. In recent years, these biosurfactants are increasingly studied as possible biomedical agents with expressed immunological activities. Applications of trehalolipids from Rhodococcus, predominantly cell-bound, in biomedicine are also attractive because their cost drawback could be less significant for high-value products. The review summarizes recent findings in immunomodulatory activities of trehalolipid biosurfactants from nonpathogenic Rhodococcus and related actinobacteria and compares their biomedical potential with well-known immunomodifying properties of trehalose dimycolates from Mycobacterium tuberculosis. Molecular mechanisms of trehalolipid interactions with immunocompetent cells are also discussed.


Subject(s)
Immunologic Factors/biosynthesis , Immunologic Factors/immunology , Lipids/immunology , Rhodococcus/classification , Rhodococcus/metabolism , Surface-Active Agents/metabolism , Animals , Mice , Rhodococcus/immunology , Species Specificity
4.
J Interferon Cytokine Res ; 35(3): 222-31, 2015 Mar.
Article in English | MEDLINE | ID: mdl-25291432

ABSTRACT

Interleukin (IL)-4 promotes the regression of granulomas during the late phase of Rhodococcus aurantiacus infection. In this study, the contribution of IL-4 to the initial response against this bacterium was investigated using IL-4-deficient mice. Compared with wild-type (WT) mice, IL-4-deficient mice displayed remarkably lower tumor necrosis factor (TNF)-α and IL-6 secretion in the liver, spleen, and blood at the initial phase of infection, along with improved survival. IL-4-deficient mice also showed diminished IL-10 secretion in the spleen and blood; however, hepatic IL-10 levels were similar to those observed in WT animals, and were concomitant with augmented interferon (IFN)-γ production and decreased bacterial burden in the liver at the early infection phase. Histological examination revealed reduced hepatic granuloma formation in infected IL-4-deficient mice. On challenge with heat-killed R. aurantiacus, IL-4-deficient mouse macrophages showed reduced expression of TNF-α, IL-6, and IL-10 at both the gene and protein levels compared with WT mouse cells. These findings indicate that during the initiation of R. aurantiacus-induced inflammation, IL-4 deficiency attenuates cytokine responses in macrophages, which contributes to amelioration in mouse survival and reduction of granulomatous inflammation, and augments a hepatic IFN-γ response which transiently accelerates bacterial elimination.


Subject(s)
Actinomycetales Infections/immunology , Granuloma/immunology , Immunotherapy/methods , Interleukin-4/metabolism , Rhodococcus/immunology , Sarcoidosis/immunology , Actinomycetales Infections/therapy , Animals , Bacterial Load , Female , Granuloma/prevention & control , Humans , Immunity, Innate , Inflammation , Interleukin-4/genetics , Mice , Mice, Inbred C57BL , Mice, Knockout , Sarcoidosis/therapy
5.
Immunotherapy ; 3(4): 577-83, 2011 Apr.
Article in English | MEDLINE | ID: mdl-21463197

ABSTRACT

This article describes the first use of heat-killed, borate-buffered preparations of aerobic actinomycetales to immunize pregnant animals in order to determine the effect on their pregnancy and fertility and the survival coefficients of their offspring. Pregnant rats received three injections of Gordonia bronchialis, Rhodococcus coprophylus or physiological saline and a proportion of their offspring were challenged with live Trypanosoma cruzi at the time of weaning. Levels of parasitemia and, in some animals, of the cytokines IFN-γ and IL-10 were measured. The progress of pregnancy, fertility and survival of offspring were unaffected by the maternal immunizations. The offspring of rats immunized with G. bronchialis displayed significantly reduced parasitemias, with increased levels of IFN-γ and reduced levels of IL-10, 4 days after challenge. The offspring of rats immunized with R. coprophylus displayed greater parasitemias than did those of the control group. These unexpected results are discussed and their causation considered.


Subject(s)
Actinomycetales/immunology , Chagas Disease/prevention & control , Immunologic Factors/administration & dosage , Immunologic Factors/immunology , Parasitemia/prevention & control , Trypanosoma cruzi/pathogenicity , Animals , Antibodies, Protozoan/blood , Chagas Disease/immunology , Chagas Disease/parasitology , Disease Models, Animal , Female , Gordonia Bacterium/immunology , Interferon-gamma/blood , Interleukin-10/blood , Male , Maternal-Fetal Exchange , Parasitemia/immunology , Parasitemia/parasitology , Pregnancy , Rats , Rhodococcus/immunology
6.
J Immunol ; 185(1): 376-86, 2010 Jul 01.
Article in English | MEDLINE | ID: mdl-20519644

ABSTRACT

The CD1 family of Ag-presenting molecules is able to display lipids to T cells by binding them within a hydrophobic groove connected to the protein surface. In particular, the CD1b isotype is capable of binding ligands with greatly varying alkyl chain lengths through a complex network of interconnected hydrophobic pockets. Interestingly, mycobacterial lipids such as glucose monomycolate exclusively bind to CD1b. We determined the crystal structure of one of the three expressed bovine CD1b proteins, CD1b3, in complex with endogenous ligands, identified by mass spectrometry as a mixture of phosphatidylcholine and phosphatidylethanolamine, and analyzed the ability of the protein to bind glycolipids in vitro. The structure reveals a complex binding groove architecture, similar to the human ortholog but with consequential differences. Intriguingly, in bovine CD1b3 only the A', C' and F' pockets are present, whereas the T' pocket previously described in human CD1b is closed. This different pocket conformation could affect the ability of boCD1b3 to recognize lipids with long acyl chains such as glucose monomycolate. However, even in the absence of a T' tunnel, bovine CD1b3 is able to bind mycolates from Rhodococcus ruber in vitro.


Subject(s)
Antigens, CD1/chemistry , Antigens, CD1/metabolism , Amino Acid Sequence , Animals , Cattle , Crystallography, X-Ray , Glycolipids/chemistry , Glycolipids/metabolism , Humans , Ligands , Models, Molecular , Molecular Sequence Data , Mycolic Acids/chemistry , Mycolic Acids/metabolism , Phosphatidylcholines/chemistry , Phosphatidylcholines/metabolism , Phosphatidylethanolamines/chemistry , Phosphatidylethanolamines/metabolism , Protein Binding/immunology , Protein Structure, Tertiary , Rhodococcus/immunology , Rhodococcus/metabolism , Sequence Homology, Amino Acid , Tandem Mass Spectrometry
7.
Angiology ; 61(5): 437-42, 2010 Jul.
Article in English | MEDLINE | ID: mdl-20498142

ABSTRACT

We assessed the effect of novel immunotherapeutic heat-killed bacterial (Actinomycetales) preparations on the development of myointimal hyperplasia (MIH) in a rat carotid balloon trauma model and the effect on the immune response by measuring the expression of interferon gamma (IFN-gamma; (Th1) and interleukin 4 (IL-4; Th2). There was a significant reduction (P < .001) in intima/media ratios (mean +/- SEM) in the rats treated by immunomodulation (0.52 +/- 0.03 Gordonia bronchialis, 0.60 +/- 0.03 Rhodococcus coprophilus, 0.43 +/- 0.03 Tsukamurella inchonensis, 0.37 +/- 0.03 Mycobacterium vaccae), in comparison with untreated controls (0.91 +/- 0.05). Postballoon trauma G bronchialis increased messenger RNA (mRNA) IFN-gamma (P < .02) and reduced mRNA IL-4 (P < .05). R coprophilus, T inchonensis, and M vaccae significantly increased production of mRNA IFN-gamma (P < .001). R coprophilus and M vaccae also decreased production of mRNA IL-4 (P < .05, P < .01). Treatment with heat-killed Actinomycetales inhibits MIH through a combination of enhanced Th1 and attenuated Th2 response. Immunomodulation may provide a novel therapeutic option to prevent restenosis.


Subject(s)
Carotid Stenosis/prevention & control , Catheterization/adverse effects , Fibromuscular Dysplasia/prevention & control , Immunologic Factors/pharmacology , Interferon-gamma/blood , Interleukin-4/blood , Actinomycetales/immunology , Animals , Bacterial Vaccines/immunology , Carotid Stenosis/immunology , Carotid Stenosis/pathology , Fibromuscular Dysplasia/immunology , Fibromuscular Dysplasia/pathology , Gordonia Bacterium/immunology , Male , Rats , Rats, Sprague-Dawley , Rhodococcus/immunology , Th1 Cells/drug effects , Th1 Cells/immunology , Th2 Cells/drug effects , Th2 Cells/immunology , Tunica Intima/immunology , Tunica Intima/pathology , Tunica Media/immunology , Tunica Media/pathology
8.
Microbes Infect ; 10(14-15): 1450-8, 2008.
Article in English | MEDLINE | ID: mdl-18834949

ABSTRACT

The interaction between interleukin-10 (IL-10) and interleukin-6 (IL-6) was investigated in the inflammatory response to Rhodococcus aurantiacus (R. aurantiacus) infection, in which both cytokines act as anti-inflammatory cytokines. Compared with wild-type (WT) counterparts, IL-6 gene-deficient (IL-6(-)/(-)) mice mounted a more robust production of IL-10 and tumor necrosis factor-alpha (TNF-alpha) during the initial phase of infection. Administration of anti-IL-10 antibody resulted in all the mice dying within 3 days post-infection as well as a further elevated TNF-alpha release. In vitro challenge of the macrophages from IL-6(-)/(-) and WT mice with heat-killed R. aurantiacus also showed similar results. Addition of exogenous IL-6 depressed IL-10 and TNF-alpha production by either IL-6(-)/(-) mice or IL-6(-)/(-) mouse macrophages. Likewise, WT mouse macrophages pretreated with anti-IL-10 or anti-IL-6 antibody exhibited increased production of TNF-alpha and IL-6 or IL-10 respectively. Moreover, neutralization of both IL-10 and IL-6 induced a further increase in TNF-alpha production by WT mouse cells. Overall, we conclude that IL-10 is a key element in protecting mice against mortality, and that IL-10 and IL-6 production are negatively regulated by each other although they are additive in suppressing TNF-alpha release in R. aurantiacus-infected mouse model.


Subject(s)
Actinomycetales Infections/immunology , Interleukin-10/immunology , Interleukin-6/immunology , Rhodococcus/immunology , Animals , Female , Interleukin-6/deficiency , Macrophages/microbiology , Male , Mice , Mice, Inbred C57BL , Mice, Knockout , Survival Analysis , Tumor Necrosis Factor-alpha/metabolism
9.
Ann Allergy Asthma Immunol ; 98(3): 294-8, 2007 Mar.
Article in English | MEDLINE | ID: mdl-17378264

ABSTRACT

BACKGROUND: The functional importance of CD2 in vivo is currently the subject of discussion. OBJECTIVE: To describe a 47-year-old white man with systemic Rhodococcus infection, a rarely observed opportunistic disease, secondary to severe lymphopenia. METHODS: We extensively characterized lymphocyte phenotype and function. RESULTS: Both CD4+ and CD8+ T cells were severely diminished, with a particular reduction in alpha:beta T cells. Human immunodeficiency virus infection was excluded. CD2 expression was decreased not only on T cells but also on nonaffected natural killer cells. Production of interferon-gamma interleukin 2, and tumor necrosis factor a was normal. Neither B-cell numbers nor humoral immune responses were affected. In addition, adhesion molecules CD11a, CD54, and CD154 were normally expressed, as were the costimulatory molecules CD28, CD80, and CD86. CONCLUSIONS: We hypothesize that prolonged disturbance of CD2 expression led to an acquired severe cellular immunodeficiency. This underlines the importance of CD2 in vivo, where it may play a role in the fine regulation of T-cell proliferation.


Subject(s)
Actinomycetales Infections/immunology , CD2 Antigens , Lymphopenia/immunology , Rhodococcus/immunology , T-Lymphocytes/pathology , Actinomycetales Infections/complications , CD2 Antigens/biosynthesis , Cells, Cultured , Humans , Lymphopenia/etiology , Male , Middle Aged , T-Lymphocytes/immunology , T-Lymphocytes/metabolism
10.
Int Immunopharmacol ; 6(9): 1441-50, 2006 Sep.
Article in English | MEDLINE | ID: mdl-16846838

ABSTRACT

In a search for novel immunostimulating substances we detected that culture supernatants of the gram-positive phytopathogenic bacterium, Rhodococcus fascians, were able to induce cytokine release (TNF(alpha)) from mouse peritoneal macrophages. Monoclonal antibodies were generated against the active principle, and were employed for its isolation and partial characterization as a high molecular (MW>100 kDa) glycoprotein. In addition, methods practicable for its biotechnological preparation and several ELISA variants for its determination were developed.


Subject(s)
Glycoproteins/isolation & purification , Immunologic Factors/isolation & purification , Rhodococcus/chemistry , Rhodococcus/immunology , Animals , Antibodies, Bacterial/biosynthesis , Antibodies, Bacterial/chemistry , Antibodies, Monoclonal/biosynthesis , Antibodies, Monoclonal/chemistry , Antigens, Bacterial/chemistry , Antigens, Bacterial/immunology , Antigens, Bacterial/isolation & purification , Cell Line , Chromatography, Affinity , Chromatography, Gel , Chromatography, Ion Exchange , Female , Glycoproteins/chemistry , Glycoproteins/immunology , Immunologic Factors/biosynthesis , Immunologic Factors/chemistry , Mice
11.
J Immunol ; 177(1): 642-50, 2006 Jul 01.
Article in English | MEDLINE | ID: mdl-16785562

ABSTRACT

After i.v. inoculation with Rhodococcus aurantiacus, wild-type (WT) mice develop nonnecrotic, epithelioid granulomas. Because a high level of TNF-alpha is observed during the initial phase postinfection, we examined the extent to which TNF-alpha contributes to granulomatous inflammation using TNF-alpha gene-deficient (TNF-alpha(-/-)) mice. Despite a lack of R. aurantiacus proliferation, TNF-alpha(-/-) mice displayed high mortality rates within 5 days postinfection, as well as a high level of IL-6 in their spleens. Histological examination showed an absence of granuloma formation in TNF-alpha(-/-) mice. Pretreatment of TNF-alpha(-/-) mice with rTNF-alpha failed to restore this granuloma formation but accelerated bacterial removal and cellular recruitment. This rTNF-alpha administration also attenuated IL-6 production, resulting in increased survival rates of TNF-alpha(-/-) mice. Heat-killed R. aurantiacus induced in vitro enhanced mRNA expression and production of IL-6 in macrophages and DCs from TNF-alpha(-/-) mice when compared with WT controls, and treatment of TNF-alpha(-/-) mouse cells with rTNF-alpha decreased the IL-6 secretion. Moreover, anti-TNF-alpha or anti-IL-6 treatment increased IL-6 or TNF-alpha production by WT mouse cells, respectively. These data suggest that the production of TNF-alpha and IL-6 can be negatively regulated by each other. Administration of rIFN-gamma to TNF-alpha(-/-) mice caused immature granulomas in livers, and treatment with both rTNF-alpha and rIFN-gamma led to the formation of mature granulomas. Overall, TNF-alpha appears crucial for bacterial clearance, cellular recruitment, and granuloma formation. The balance between TNF-alpha and IL-6 during the early phase of infection controls the development of the inflammatory response to R. aurantiacus infection.


Subject(s)
Actinomycetales Infections/immunology , Granuloma/immunology , Granuloma/microbiology , Interleukin-6/physiology , Rhodococcus/immunology , Tumor Necrosis Factor-alpha/physiology , Actinomycetales Infections/genetics , Actinomycetales Infections/mortality , Animals , Cells, Cultured , Cytokines/biosynthesis , Cytokines/genetics , Cytokines/metabolism , Down-Regulation/genetics , Down-Regulation/immunology , Female , Granuloma/genetics , Granuloma/mortality , Inflammation/genetics , Inflammation/immunology , Inflammation/microbiology , Inflammation/mortality , Interleukin-6/antagonists & inhibitors , Interleukin-6/biosynthesis , Kinetics , Liver/immunology , Liver/metabolism , Liver/microbiology , Liver/pathology , Mice , Mice, Inbred C57BL , Mice, Knockout , RNA, Messenger/biosynthesis , Rhodococcus/growth & development , Spleen/immunology , Spleen/metabolism , Spleen/microbiology , Spleen/pathology , Tumor Necrosis Factor-alpha/deficiency , Tumor Necrosis Factor-alpha/genetics
12.
Immunology ; 110(4): 501-6, 2003 Dec.
Article in English | MEDLINE | ID: mdl-14632648

ABSTRACT

After intravenous injection of Rhodococcus aurantiacus normal mice develop non-necrotic granulomas, the formation of which is dependent on endogenous interferon-gamma (IFN-gamma). In the early phase of R. aurantiacus infection a high level of endogenous interleukin-6 (IL-6) is detected in the spleen extracts, though its importance is unknown. Using IL-6 knockout (IL-6-/-) mice, we studied the role of IL-6 in granulomatous inflammation induced by R. aurantiacus. The size of granulomas generated in IL-6-/- mice was significantly larger than that of wild-type (IL-6+/+) mice at 2 weeks postinjection (p.i). Moreover, central necrosis of the granuloma was observed in IL-6-/- mice but not in IL-6+/+ controls. Titres of endogenous IFN-gamma and tumour necrosis factor-alpha (TNF-alpha) were markedly increased in the spleens and livers of IL-6-/- mice in comparison with IL-6+/+ mice at days 1 through 3 p.i. In vivo administration of either an anti-IFN-gamma monoclonal antibody (mAb) or anti-TNF-alpha mAb to IL-6-/- mice reduced the number and size of granulomas, and prevented formation of necrotic granulomas. In addition, the production of endogenous IFN-gamma and TNF-alpha in the early phase of R. aurantiacus infection by IL-6-/- mice was suppressed by treatment with recombinant IL-6 (rIL-6). This suppression of IFN-gamma and TNF-alpha production was followed by a reduction in the number and size of central necrotic granulomas at 2 weeks p.i. These findings suggest that overproduction of IFN-gamma and TNF-alpha induces central necrotic granuloma formation in IL-6-/- mice, and that IL-6 down-regulates granulomatous inflammation reaction in response to R. aurantiacus infection by modulating production of IFN-gamma and TNF-alpha.


Subject(s)
Actinomycetales Infections/immunology , Granuloma/immunology , Interleukin-6/immunology , Rhodococcus/immunology , Actinomycetales Infections/pathology , Animals , Antibodies, Monoclonal/immunology , Enzyme-Linked Immunosorbent Assay/methods , Granuloma/pathology , Immunosuppression Therapy , Inflammation/immunology , Inflammation/pathology , Interferon-gamma/analysis , Interferon-gamma/immunology , Interleukin-6/analysis , Kinetics , Liver/immunology , Liver/pathology , Mice , Mice, Knockout , Necrosis , Rhodococcus/growth & development , Spleen/immunology , Tumor Necrosis Factor-alpha/analysis , Tumor Necrosis Factor-alpha/immunology , Up-Regulation/immunology
14.
J Med Microbiol ; 50(8): 688-694, 2001 Aug.
Article in English | MEDLINE | ID: mdl-11478672

ABSTRACT

Intravenous injection of Rhodococcus aurantiacus into mice causes granulomatous inflammation dependent on endogenous interferon-gamma (IFN-gamma). This study investigated the mechanism of granuloma formation with an adoptive transfer system in IFN-gamma knockout (IFN-gamma(-/-)) mice. IFN-gamma(-/-) mice infected with R. aurantiacus did not develop granulomas, and high titres of endogenous interleukin-10 (IL-10) were detected in spleen extracts at 2 weeks after infection. The adoptive transfer of splenocytes from infected wild-type (IFN-gamma(+/+)) mice did not restore granuloma formation, although this treatment diminished IL-10 production in IFN-gamma(-/-) mice. Adoptive transfer of splenocytes from infected IFN-gamma(-/-) mice into infected IFN-gamma(+/+) reduced granuloma formation. These results suggest that splenocytes of IFN-gamma(-/-) mice suppress granuloma formation. On the other hand, although IFN-gamma production induced by R. aurantiacus infection was detected in nude mice, which are deficient in T cells, granuloma formation was not induced in them. However, adoptive transfer of immune splenocytes from either IFN-gamma(+/+) mice or IFN-gamma(-/-) mice could induce granuloma formation. This means that splenocytes of IFN-gamma(-/-) mice have the ability to both induce and suppress granuloma formation. Induction of granuloma is probably dependent on both T cells and IFN-gamma produced by non-T cells. It is suggested that the role of T cells in granuloma formation is not dependent on their IFN-gamma production.


Subject(s)
Actinomycetales Infections/immunology , Granuloma/immunology , Interferon-gamma/biosynthesis , Rhodococcus/physiology , T-Lymphocytes/immunology , Animals , Colony Count, Microbial , Female , Granuloma/microbiology , Granuloma/prevention & control , Immunotherapy, Adoptive , Interferon-gamma/genetics , Interferon-gamma/immunology , Interleukin-10/biosynthesis , Interleukin-10/immunology , Kinetics , Liver/cytology , Liver/pathology , Mice , Mice, Inbred BALB C , Mice, Inbred C57BL , Mice, Knockout , Mice, Nude , Rhodococcus/immunology , Spleen/cytology , Spleen/immunology , T-Lymphocytes/cytology
15.
Microbiol Immunol ; 43(8): 785-93, 1999.
Article in English | MEDLINE | ID: mdl-10524797

ABSTRACT

Antibody production against the trehalose 6,6'-dimycolate (TDM, cord factor) of Rhodococcus ruber, a non-pathogenic species of the Actinomycetales group, was investigated in mice by repeated intraperitoneal injection of TDM in water-in-oil-in-water micelles without carrier protein. The antigenic TDM was isolated and purified chromatographically from the chloroform-methanol extractable lipids of R. ruber. The hydrophobic moiety of this TDM was composed of two molecules of monoenoic or dienoic alpha-mycolic acids with a carbon chain length ranging from C44 to C48 centering at C46. To detect the antibody, an enzyme-linked immunosorbent assay (ELISA) system was employed using plastic plates coated with TDM. The antibody reacted against the TDM of R. ruber. The antibody was reactive in similar fashion against glycosyl monomycolates differing in the carbohydrate moiety, such as that of glucose mycolate (GM) and mannose mycolate (MM), obtained from R. ruber. Moreover, the antibody reacted against mycolic acid methyl ester itself when it was used as the antigen in ELISA, and trehalose did not absorb the antibody to TDM or inhibit the reaction. These results indicate that the epitope of TDM recognized by the antibody is mycolic acid, an extremely hydrophobic part of the molecule. Next, we prepared monoclonal anti-TDM antibody (moAb) in mice myeloma cells to examine its biological activities and the role of humoral immunity in mycobacterial infection. MoAb reacted against the TDM, glycosyl mycolate, and mycolic acid methyl ester in ELISA in the same manner as our polyclonal antibody did. The administration of moAb suppressed granuloma formation in the lungs, spleen, and liver induced by TDM and inhibited the production of interleukin-1 (IL-1) and chemotactic factor, which is reported to precede granuloma formation.


Subject(s)
Antibodies, Bacterial/immunology , Cord Factors/immunology , Rhodococcus/immunology , Absorption , Animals , Antibodies, Bacterial/biosynthesis , Antibodies, Monoclonal/immunology , Carbohydrates/immunology , Chemotactic Factors/biosynthesis , Cord Factors/adverse effects , Glycolipids/immunology , Granuloma/etiology , Granuloma/immunology , Interleukin-1/biosynthesis , Male , Mice , Mice, Inbred ICR , Mycolic Acids/immunology
16.
Vet Microbiol ; 65(3): 241-54, 1999 Mar 12.
Article in English | MEDLINE | ID: mdl-10189199

ABSTRACT

The aim of this study was to evaluate the influence of age and plasma treatment on neutrophil phagocytosis, CD18 expression and serum opsonic capacity in foals in field settings. Microbial infections constitute a large threat in young foals and neutrophil functions are crucial for the defense. Blood samples were obtained from 13 foals at seven time points between the ages of 2 and 56 days and once from 16 adult horses. Six of the foals were treated with adult plasma at the age of 1 week. Neutrophil phagocytosis of yeast after various opsonizations and the expression of complement adhesion receptor CD18 were analysed by flow cytometry. Autologous serum opsonization resulted in 52+/-6.1% phagocytic neutrophils in 2-day-old foals (n = 12), a significantly lower rate than in adult horses (mean 84+/-3.1%; n = 16). In foals, yeast ingestion per neutrophil was also lower than in adults. Opsonic capacity increased with age (p < 0.05), reaching adult levels at 3-4 weeks. An increase in serum opsonic capacity followed plasma treatment (p < 0.05). The phagocytic capacity of foal neutrophils at the time-points studied was equal to or higher than that in the adults, when pooled adult horse serum or anti-yeast IgG was used as opsonin. In foals, serum IgG concentration was negatively correlated to serum opsonic capacity. CD18 receptor expression was higher in neutrophils from foals (<21 days old) than in those from adult horses (p < 0.05). The results indicate that foals are transiently deficient in serum opsonic capacity, which negatively affects their capacity for neutrophil phagocytosis. These changes in serum opsonins, unrelated to IgG, may be important factors in susceptibility to infections in foals.


Subject(s)
CD18 Antigens/biosynthesis , Gene Expression Regulation , Horse Diseases/immunology , Neutrophils/immunology , Phagocytosis/immunology , Actinomycetales Infections/prevention & control , Age Factors , Animals , CD18 Antigens/genetics , CD18 Antigens/immunology , Electrophoresis, Agar Gel/veterinary , Female , Flow Cytometry/veterinary , Horses , Immunoglobulin G/blood , Male , Opsonin Proteins/blood , Opsonin Proteins/immunology , Plasma/immunology , Rhodococcus/immunology , Saccharomyces cerevisiae/immunology
17.
Curr Microbiol ; 33(1): 26-30, 1996 Jul.
Article in English | MEDLINE | ID: mdl-8661681

ABSTRACT

By sequence analysis, a gene encoding a homolog of the 17-kDa protein antigen of the Gram-negative pathogen Brucella abortus (Hemmen et al., Clin Diagn Lab Immunol 2: 263, 1995) was identified in the nocardioform actinomycete Rhodococcus sp. NI86/21. Database searching also revealed a partial human cDNA sequence for a putative eukaryotic homolog of this presumptive Brucella-specific protein. These proteins display a low but significant level of similarity with lumazine synthases involved in bacterial riboflavin biosynthesis. In the upstream region, a Rhodococcus gene for a putative regulatory protein of the AsnC family is located.


Subject(s)
Antigens, Bacterial/genetics , Bacterial Proteins/genetics , Brucella/genetics , Brucella/immunology , Genes, Bacterial , Multigene Family , Rhodococcus/genetics , Amino Acid Sequence , Antigens, Bacterial/chemistry , Base Sequence , DNA, Bacterial/genetics , DNA, Complementary/genetics , Humans , Molecular Sequence Data , Molecular Weight , Open Reading Frames , Rhodococcus/immunology , Sequence Homology, Amino Acid
18.
J Clin Microbiol ; 29(3): 439-43, 1991 Mar.
Article in English | MEDLINE | ID: mdl-2037660

ABSTRACT

Antigens of Rhodococcus equi were analyzed by immunoblotting with naturally infected foal sera. Immunoblots of whole-cell antigen preparations of clinical isolates of R. equi revealed that major protein bands with molecular masses of 15 to 17 kDa were present in all clinical isolates tested and all isolates virulent for mice. In contrast, the 15- to 17-kDa antigens were not identified by immunoblotting in ATCC 6939, a type strain of R. equi that was avirulent for mice. Whole-cell antigens of 102 environmental isolates were investigated by immunoblotting and the mouse pathogenicity test. Twenty-five of these isolates were demonstrated to contain the 15- to 17-kDa antigens by immunoblotting and were virulent for mice. The remaining 77 environmental isolates lacked the 15- to 17-kDa antigens and were avirulent for mice. These data suggest that the diffuse 15- to 17-kDa proteins are virulence-associated antigens with immunogenicity in foals and that they may be useful in marking virulent R. equi contamination in the environment of a horse-breeding farm.


Subject(s)
Actinomycetales Infections/veterinary , Antigens, Bacterial/isolation & purification , Horse Diseases/immunology , Rhodococcus/immunology , Actinomycetales Infections/immunology , Animals , Antigens, Bacterial/chemistry , Biomarkers , Horses , Immunoblotting , Lung/immunology , Lymph Nodes/immunology , Mice , Molecular Weight , Rhodococcus/isolation & purification , Rhodococcus/pathogenicity , Serotyping , Soil Microbiology , Virulence/immunology
19.
Vet Microbiol ; 26(4): 323-33, 1991 Feb 15.
Article in English | MEDLINE | ID: mdl-2031302

ABSTRACT

Rhodococcus equi produces two exoenzymes (REE), a cholesterol oxidase in large amounts and a phospholipase C, which cause lysis of sheep red blood cells (SRBC) sensitized with Staphylococcus aureus beta toxin. Two immunization studies were done in foals to determine the role of antibody to REE in protection against R. equi pneumonia. In the first study, three foals (mean age 10 days) were vaccinated four times at 2-week intervals with over 1 million units of partially purified exoenzymes (PREE). In the second study, three foals (mean age 19 days) were administered plasma from an adult horse vaccinated with PREE. Relatively low titres (16-32) of neutralizing antibody were detected in the foals of the former group, and passive transfer of neutralizing antibody (titres 32-64) occurred in the latter. Following immunization, principal foals and an equal number of similarly aged nonimmunized foals were challenged by aerosol with 1 x 10(10) live R. equi per day for 5 consecutive days. No severe clinical pneumonia developed in either group and, with one exception, only minor and resolving lung abscesses developed in these foals. These studies showed that antibody response of foals to immunization with PREE was poor, antibody to PREE did not prevent foals from developing lung abscesses following experimental infection, and that foals even as young as 3 weeks of age may be largely refractory to aerosol challenge with virulent R. equi.


Subject(s)
Actinomycetales Infections/veterinary , Antibodies, Bacterial/immunology , Horse Diseases/prevention & control , Pneumonia/veterinary , Rhodococcus/immunology , Actinomycetales Infections/prevention & control , Animals , Antibodies, Bacterial/biosynthesis , Antigens, Bacterial/immunology , Antigens, Bacterial/isolation & purification , Bacterial Proteins/immunology , Bacterial Proteins/isolation & purification , Bacterial Vaccines/immunology , Cholesterol Oxidase/immunology , Cholesterol Oxidase/isolation & purification , Chromatography, Gel , Electrophoresis, Polyacrylamide Gel , Horses , Immunization, Passive , Lung/pathology , Pneumonia/prevention & control , Type C Phospholipases/immunology , Type C Phospholipases/isolation & purification , Vaccination/veterinary
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