scholarly journals Protective Live Oral Brucellosis Vaccines Stimulate Th1 and Th17 Cell Responses

2011 ◽  
Vol 79 (10) ◽  
pp. 4165-4174 ◽  
Author(s):  
Beata Clapp ◽  
Jerod A. Skyberg ◽  
Xinghong Yang ◽  
Theresa Thornburg ◽  
Nancy Walters ◽  
...  
Keyword(s):  
Brucella Melitensis ◽  
Natural Infection ◽  
Oral Immunization ◽  
Oral Route ◽  
Interleukin 17 ◽  
Content Type ◽  
Unpasteurized Milk ◽  
Ifn Γ ◽  
Feral Animals ◽  
Immunocompetent Mice

ABSTRACTZoonotic transmission of brucellosis often results from exposure toBrucella-infected livestock, feral animals, or wildlife or frequently via consumption of unpasteurized milk products or raw meat. Since natural infection of humans often occurs by the oral route, mucosal vaccination may offer a means to confer protection for both mucosal and systemic tissues. Significant efforts have focused on developing a live brucellosis vaccine, and deletion of theznuAgene involved in zinc transport has been found to attenuateBrucella abortus. A similar mutation has been adapted forBrucella melitensisand tested to determine whether oral administration of ΔznuAB. melitensiscan confer protection against nasalB. melitensischallenge. A single oral vaccination with ΔznuAB. melitensisrapidly cleared from mice within 2 weeks and effectively protected mice upon nasal challenge with wild-typeB. melitensis16M. In 83% of the vaccinated mice, no detectable brucellae were found in their spleens, unlike with phosphate-buffered saline (PBS)-dosed mice, and vaccination also enhanced the clearance of brucellae from the lungs. Moreover, vaccinated gamma interferon-deficient (IFN-γ−/−) mice also showed protection in both spleens and lungs, albeit protection that was not as effective as in immunocompetent mice. Although IFN-γ, interleukin 17 (IL-17), and IL-22 were stimulated by these live vaccines, only RB51-mediated protection was codependent upon IL-17 in BALB/c mice. These data suggest that oral immunization with the live, attenuated ΔznuAB. melitensisvaccine provides an attractive strategy to protect against inhalational infection with virulentB. melitensis.

scholarly journals Pulmonary Interleukin-17-Positive Lymphocytes Increase during Pneumocystis murina Infection but Are Not Required for Clearance of Pneumocystis

2017 ◽  
Vol 85 (7) ◽  
Author(s):  
Chiara Ripamonti ◽  
Lisa R. Bishop ◽  
Joseph A. Kovacs
Keyword(s):  
T Cells ◽  
Fungal Infections ◽  
Intracellular Cytokine Staining ◽  
Γδ T Cells ◽  
Interleukin 17 ◽  
Content Type ◽  
Immunosuppressed Patients ◽  
Ifn Γ ◽  
Immunocompetent Mice ◽  
Deficient Mice

ABSTRACT Pneumocystis remains an important pathogen of immunosuppressed patients, causing a potentially life-threatening pneumonia. Despite its medical importance, the immune responses required to control infection, including the role of interleukin-17 (IL-17), which is important in controlling other fungal infections, have not been clearly defined. Using flow cytometry and intracellular cytokine staining after stimulation with phorbol myristate acetate and ionomycin, we examined gamma interferon (IFN-γ), IL-4, IL-5, and IL-17 production by lung lymphocytes in immunocompetent C57BL/6 mice over time following infection with Pneumocystis murina. We also examined the clearance of Pneumocystis infection in IL-17A-deficient mice. The production of both IFN-γ and IL-17 by pulmonary lymphocytes increased during infection, with maximum production at approximately days 35 to 40, coinciding with peak Pneumocystis levels in the lungs, while minimal changes were seen in IL-4- and IL-5-positive cells. The proportion of cells producing IFN-γ was consistently higher than for cells producing IL-17, with peak levels of ∼25 to 30% of CD3+ T cells for the former compared to ∼15% for the latter. Both CD4+ T cells and γδ T cells produced IL-17. Administration of anti-IFN-γ antibody led to a decrease in IFN-γ-positive cells, and an increase in IL-5-positive cells, but did not impact clearance of Pneumocystis infection. Despite the increases in IL-17 production during infection, IL-17A-deficient mice cleared Pneumocystis infection with kinetics similar to C57BL/6 mice. Thus, while IL-17 production in the lungs is increased during Pneumocystis infection in immunocompetent mice, IL-17A is not required for control of Pneumocystis infection.

scholarly journals Animal Model To Study Klebsiella pneumoniae Gastrointestinal Colonization and Host-to-Host Transmission

2020 ◽  
Vol 88 (11) ◽  
Author(s):  
Taylor M. Young ◽  
Andrew S. Bray ◽  
Ravinder K. Nagpal ◽  
David L. Caudell ◽  
Hariom Yadav ◽  
...  
Keyword(s):  
Klebsiella Pneumoniae ◽  
Close Contact ◽  
Epidemiological Studies ◽  
Multidrug Resistant ◽  
Transmission Efficiency ◽  
Oral Route ◽  
Human Infection ◽  
Gi Tract ◽  
Content Type ◽  
Immunocompetent Mice

ABSTRACT An important yet poorly understood facet of the life cycle of a successful pathogen is host-to-host transmission. Hospital-acquired infections (HAI) resulting from the transmission of drug-resistant pathogens affect hundreds of millions of patients worldwide. Klebsiella pneumoniae, a Gram-negative bacterium, is notorious for causing HAI, with many of these infections difficult to treat, as K. pneumoniae has become multidrug resistant. Epidemiological studies suggest that K. pneumoniae host-to-host transmission requires close contact and generally occurs through the fecal-oral route. Here, we describe a murine model that can be utilized to study mucosal (oropharynx and gastrointestinal [GI]) colonization, shedding within feces, and transmission of K. pneumoniae through the fecal-oral route. Using an oral route of inoculation, and fecal shedding as a marker for GI colonization, we showed that K. pneumoniae can asymptomatically colonize the GI tract in immunocompetent mice and modifies the host GI microbiota. Colonization density within the GI tract and levels of shedding in the feces differed among the clinical isolates tested. A hypervirulent K. pneumoniae isolate was able to translocate from the GI tract and cause hepatic infection that mimicked the route of human infection. Expression of the capsule was required for colonization and, in turn, robust shedding. Furthermore, K. pneumoniae carrier mice were able to transmit to uninfected cohabitating mice. Lastly, treatment with antibiotics led to changes in the host microbiota and development of a transient supershedder phenotype, which enhanced transmission efficiency. Thus, this model can be used to determine the contribution of host and bacterial factors toward K. pneumoniae dissemination.

scholarly journals Coinfection with Enterohepatic Helicobacter Species Can Ameliorate or Promote Helicobacter pylori-Induced Gastric Pathology in C57BL/6 Mice

2011 ◽  
Vol 79 (10) ◽  
pp. 3861-3871 ◽  
Author(s):  
Zhongming Ge ◽  
Yan Feng ◽  
Sureshkumar Muthupalani ◽  
Laura Lemke Eurell ◽  
Nancy S. Taylor ◽  
...  
Keyword(s):  
Helicobacter Pylori ◽  
Interleukin 17 ◽  
Mrna Levels ◽  
Cytokine Mrna ◽  
Content Type ◽  
Time Points ◽  
Gastric Pathology ◽  
Tnf Α ◽  
Ifn Γ ◽  
H Pylori

ABSTRACTTo investigate how different enterohepaticHelicobacterspecies (EHS) influenceHelicobacter pylorigastric pathology, C57BL/6 mice were infected withHelicobacter hepaticusorHelicobacter muridarum, followed byH. pyloriinfection 2 weeks later. Compared toH. pylori-infected mice, mice infected withH. muridarumandH. pylori(HmHp mice) developed significantly lower histopathologic activity index (HAI) scores (P< 0.0001) at 6 and 11 months postinoculation (MPI). However, mice infected withH. hepaticusandH. pylori(HhHp mice) developed more severe gastric pathology at 6 MPI (P= 0.01), with a HAI at 11 MPI (P= 0.8) similar to that ofH. pylori-infected mice.H. muridarum-mediated attenuation of gastritis in coinfected mice was associated with significant downregulation of proinflammatory Th1 (interlukin-1beta [Il-1β], gamma interferon [Ifn-γ], and tumor necrosis factor-alpha [Tnf-α]) cytokines at both time points and Th17 (Il-17A) cytokine mRNA levels at 6 MPI in murine stomachs compared to those ofH. pylori-infected mice (P< 0.01). Coinfection withH. hepaticusalso suppressedH. pylori-induced elevation of gastric Th1 cytokinesIfn-γandTnf-α(P< 0.0001) but increased Th17 cytokine mRNA levels (P= 0.028) at 6 MPI. Furthermore, mRNA levels ofIl-17Awere positively correlated with the severity of helicobacter-induced gastric pathology (HhHp>H. pylori>HmHp) (at 6 MPI,r2= 0.92,P< 0.0001; at 11 MPI,r2= 0.82,P< 0.002). Despite disparate effects on gastritis, colonization levels of gastricH. pyloriwere increased in HhHp mice (at 6 MPI) and HmHp mice (at both time points) compared to those in mono-H. pylori-infected mice. These data suggest that despite consistent downregulation of Th1 responses, EHS coinfection either attenuated or promoted the severity ofH. pylori-induced gastric pathology in C57BL/6 mice. This modulation was related to the variable effects of EHS on gastric interleukin 17 (IL-17) responses toH. pyloriinfection.

scholarly journals Role of the Aryl Hydrocarbon Receptor in the Immune Response Profile and Development of Pathology during Plasmodium berghei Anka Infection

2014 ◽  
Vol 82 (8) ◽  
pp. 3127-3140 ◽  
Author(s):  
Fatima Brant ◽  
Aline S. Miranda ◽  
Lisia Esper ◽  
David Henrique Rodrigues ◽  
Lucas Miranda Kangussu ◽  
...  
Keyword(s):  
Aryl Hydrocarbon Receptor ◽  
Plasmodium Berghei ◽  
Transforming Growth Factor ◽  
Interleukin 17 ◽  
High Morbidity ◽  
Content Type ◽  
Aryl Hydrocarbon ◽  
Tnf Α ◽  
Ifn Γ ◽  
The Brain

ABSTRACTInfection withPlasmodium falciparummay result in severe disease affecting various organs, including liver, spleen, and brain, resulting in high morbidity and mortality.Plasmodium bergheiAnka infection of mice recapitulates many features of severe human malaria. The aryl hydrocarbon receptor (AhR) is an intracellular receptor activated by ligands important in the modulation of the inflammatory response. We found that AhR-knockout (KO) mice infected withP. bergheiAnka displayed increased parasitemia, earlier mortality, enhanced leukocyte-endothelial cell interactions in the brain microvasculature, and increased inflammation in brain (interleukin-17 [IL-17] and IL-6) and liver (gamma interferon [IFN-γ] and tumor necrosis factor alpha [TNF-α]) compared to infected wild-type (WT) mice. Infected AhR-KO mice also displayed a reduction in cytokines required for host resistance, including TNF-α, IL-1β, and IFN-γ, in the brain and spleen. Infection of AhR-KO mice resulted in an increase in T regulatory cells and transforming growth factor β, IL-6, and IL-17 in the brain. AhR modulated the basal expression of SOCS3 in spleen and brain, andP. bergheiAnka infection resulted in enhanced expression of SOCS3 in brain, which was absent in infected AhR-KO mice. These data suggest that AhR-mediated control of SOCS3 expression is probably involved in the phenotype seen in infected AhR-KO mice. This is, to our knowledge, the first demonstration of a role for AhR in the pathogenesis of malaria.

scholarly journals Interleukin-17 Drives Pulmonary Eosinophilia following Repeated Exposure to Aspergillus fumigatus Conidia

2012 ◽  
Vol 80 (4) ◽  
pp. 1424-1436 ◽  
Author(s):  
Benjamin J. Murdock ◽  
Nicole R. Falkowski ◽  
Andrew B. Shreiner ◽  
Amir A. Sadighi Akha ◽  
Roderick A. McDonald ◽  
...  
Keyword(s):  
Inflammatory Response ◽  
Aspergillus Fumigatus ◽  
Minor Role ◽  
Interleukin 17 ◽  
T Helper ◽  
Content Type ◽  
Pulmonary Inflammatory Response ◽  
Ifn Γ ◽  
A Minor ◽  
Goblet Cell Metaplasia

ABSTRACTPrevious research in our laboratory has demonstrated that repeated intranasal exposure toAspergillus fumigatusconidia in C57BL/6 mice results in a chronic pulmonary inflammatory response that reaches its maximal level after four challenges. The inflammatory response is characterized by eosinophilia, goblet cell metaplasia, and T helper TH2 cytokine production, which is accompanied by sustained interleukin-17 (IL-17) expression that persists even after the TH2 response has begun to resolve. TH17 cells could develop in mice deficient in gamma interferon (IFN-γ), IL-4, or IL-10. In the lungs of IL-17 knockout mice repeatedly challenged withA. fumigatusconidia, inflammation was attenuated (with the most significant decrease occurring in eosinophils), conidial clearance was enhanced, and the early transient peak of CD4+CD25+FoxP3+cells blunted. IL-17 appeared to play only a minor role in eosinophil differentiation in the bone marrow but a central role in eosinophil extravasation from the blood into the lungs. These observations point to an expanded role for IL-17 in driving TH2-type inflammation to repeated inhalation of fungal conidia.

scholarly journals GI-19007, a Novel Saccharomyces cerevisiae-Based Therapeutic Vaccine against Tuberculosis

2017 ◽  
Vol 24 (12) ◽  
Author(s):  
Thomas H. King ◽  
Crystal A. Shanley ◽  
Zhimin Guo ◽  
Donald Bellgrau ◽  
Timothy Rodell ◽  
...  
Keyword(s):  
Bacterial Load ◽  
Therapeutic Vaccine ◽  
Lung Damage ◽  
Clinical Strain ◽  
Interleukin 17 ◽  
Lung Pathology ◽  
Content Type ◽  
Secondary Lesion ◽  
Ifn Γ ◽  
Class Ii Antigen

ABSTRACT As yet, very few vaccine candidates with activity in animals against Mycobacterium tuberculosis infection have been tested as therapeutic postexposure vaccines. We recently described two pools of mycobacterial proteins with this activity, and here we describe further studies in which four of these proteins (Rv1738, Rv2032, Rv3130, and Rv3841) were generated as a fusion polypeptide and then delivered in a novel yeast-based platform (Tarmogen) which itself has immunostimulatory properties, including activation of Toll-like receptors. This platform can deliver antigens into both the class I and class II antigen presentation pathways and stimulate strong Th1 and Th17 responses. In mice this fusion vaccine, designated GI-19007, was immunogenic and elicited strong gamma interferon (IFN-γ) and interleukin-17 (IL-17) responses; despite this, they displayed minimal prophylactic activity in mice that were subsequently infected with a virulent clinical strain. In contrast, in a therapeutic model in the guinea pig, GI-19007 significantly reduced the lung bacterial load and reduced lung pathology, particularly in terms of secondary lesion development, while significantly improving survival in one-third of these animals. In further studies in which guinea pigs were vaccinated with BCG before challenge, therapeutic vaccination with GI-19007 initially improved survival versus that of animals given BCG alone, although this protective effect was gradually lost at around 400 days after challenge. Given its apparent ability to substantially limit bacterial dissemination within and from the lungs, GI-19007 potentially can be used to limit lung damage as well as facilitating chemotherapeutic regimens in infected individuals.

scholarly journals Partial Protection against Brucella Infection in Mice by Immunization with Nonpathogenic Alphaproteobacteria

2007 ◽  
Vol 14 (10) ◽  
pp. 1296-1301 ◽  
Author(s):  
M. Victoria Delpino ◽  
Silvia M. Estein ◽  
Carlos A. Fossati ◽  
Pablo C. Baldi
Keyword(s):  
Brucella Abortus ◽  
Sinorhizobium Meliloti ◽  
Brucella Melitensis ◽  
Oral Immunization ◽  
Positive Control ◽  
Oral Route ◽  
Partial Protection ◽  
Mesorhizobium Loti ◽  
The Moment ◽  
Phosphate Buffered Saline

ABSTRACT Previous findings indicate that Brucella antigens and those from nonpathogenic alphaproteobacteria (NPAP) are cross-recognized by the immune system. We hypothesized that immunization with NPAP would protect mice from Brucella infection. Mice were immunized subcutaneously with heat-killed Ochrobactrum anthropi, Sinorhizobium meliloti, Mesorhizobium loti, Agrobacterium tumefaciens, or Brucella melitensis H38 (standard positive control) before intravenous challenge with Brucella abortus 2308. Cross-reacting serum antibodies against Brucella antigens were detected at the moment of challenge in all NPAP-immunized mice. Thirty days after B. abortus challenge, splenic CFU counts were significantly lower in mice immunized with O. anthropi, M. loti, and B. melitensis H38 than in the phosphate-buffered saline controls (protection levels were 0.80, 0.66, and 1.99 log units, respectively). In mice immunized intraperitoneally with cytosoluble extracts from NPAP or Brucella abortus, protection levels were 1.58 for the latter, 0.63 for O. anthropi, and 0.40 for M. loti. To test whether the use of live NPAP would increase protection further, mice were both immunized and challenged by the oral route. Immunization with NPAP induced a significant increase in serum immunoglobulin G (IgG), but not serum or fecal IgA, against Brucella antigens. After challenge, anti-Brucella IgA increased significantly in the sera and feces of mice orally immunized with O. anthropi. For all NPAP, protection levels were higher than those obtained with systemic immunizations but were lower than those obtained by oral immunization with heat-killed B. abortus. These results show that immunization with NPAP, especially O. anthropi, confers partial protection against Brucella challenge. However, such protection is lower than that conferred by immunization with whole Brucella or its cytosoluble fraction.

scholarly journals Recruitment of Neutrophils Mediated by Vγ2 γδ T Cells Deteriorates Liver Fibrosis Induced by Schistosoma japonicum Infection in C57BL/6 Mice

2017 ◽  
Vol 85 (8) ◽  
Author(s):  
Li Zheng ◽  
Yuan Hu ◽  
Yanjuan Wang ◽  
Xibao Huang ◽  
Yuxin Xu ◽  
...  
Keyword(s):  
T Cells ◽  
T Cell ◽  
Liver Fibrosis ◽  
Schistosoma Japonicum ◽  
Γδ T Cells ◽  
T Cell Subsets ◽  
Interleukin 17 ◽  
Content Type ◽  
Ifn Γ

ABSTRACT Conventional adaptive T cell responses contribute to the pathogenesis of Schistosoma japonicum infection, leading to liver fibrosis. However, the role of gamma-delta (γδ) T cells in this disease is less clear. γδ T cells are known to secrete interleukin-17 (IL-17) in response to infection, exerting either protective or pathogenic functions. In the present study, mice infected with S. japonicum are used to characterize the role of γδ T cells. Combined with the infection of S. japonicum, an extremely significant increase in the percentage of neutrophils in the CD45+ cells was detected (from approximately 2.45% to 46.10% in blood and from 0.18% to 7.34% in spleen). Further analysis identified two different γδ T cell subsets that have different functions in the formation of granulomas in S. japonicum-infected mice. The Vγ1 T cells secrete gamma interferon (IFN-γ) only, while the Vγ2 T cells secrete both IL-17A and IFN-γ. Both subtypes lose the ability to secrete cytokine during the late stage of infection (12 weeks postinfection). When we depleted the Vγ2 T cells in infected mice, the percentage of neutrophils in blood and spleen decreased significantly, the liver fibrosis in the granulomas was reduced, and the level of IL-17A in the serum decreased (P < 0.05). These results suggest that during S. japonicum infection, Vγ2 T cells can recruit neutrophils and aggravate liver fibrosis by secreting IL-17A. This is the first report that a subset of γδ T cells plays a partial role in the pathological process of schistosome infection.

scholarly journals Bacterial Stimulation of Toll-Like Receptor 4 Drives Macrophages To Hemophagocytose

2015 ◽  
Vol 84 (1) ◽  
pp. 47-55 ◽  
Author(s):  
Erin M. McDonald ◽  
M. Carolina Pilonieta ◽  
Heidi J. Nick ◽  
Corrella S. Detweiler
Keyword(s):  
Salmonella Enterica ◽  
Prolonged Exposure ◽  
Acute Infection ◽  
White Blood Cells ◽  
Lipoteichoic Acid ◽  
Toll Like Receptor ◽  
Toll Like Receptor 4 ◽  
Content Type ◽  
Ifn Γ ◽  
Immunocompetent Mice

During acute infection with bacteria, viruses or parasites, a fraction of macrophages engulf large numbers of red and white blood cells, a process called hemophagocytosis. Hemophagocytes persist into the chronic stage of infection and have an anti-inflammatory phenotype.Salmonella entericaserovar Typhimurium infection of immunocompetent mice results in acute followed by chronic infection, with the accumulation of hemophagocytes. The mechanism(s) that triggers a macrophage to become hemophagocytic is unknown, but it has been reported that the proinflammatory cytokine gamma interferon (IFN-γ) is responsible. We show that primary macrophages become hemophagocytic in the absence or presence of IFN-γ upon infection with Gram-negative bacterial pathogens or prolonged exposure to heat-killedSalmonella enterica, the Gram-positive bacteriumBacillus subtilis, orMycobacterium marinum. Moreover, conserved microbe-associated molecular patterns are sufficient to stimulate macrophages to hemophagocytose. Purified bacterial lipopolysaccharide (LPS) induced hemophagocytosis in resting and IFN-γ-pretreated macrophages, whereas lipoteichoic acid and synthetic unmethylated deoxycytidine-deoxyguanosine dinucleotides, which mimic bacterial DNA, induced hemophagocytosis only in IFN-γ-pretreated macrophages. Chemical inhibition or genetic deletion of Toll-like receptor 4, a pattern recognition receptor responsive to LPS, prevented bothSalmonella- and LPS-stimulated hemophagocytosis. Inhibition of NF-κB also prevented hemophagocytosis. These results indicate that recognition of microbial products by Toll-like receptors stimulates hemophagocytosis, a novel outcome of prolonged Toll-like receptor signaling, suggesting hemophagocytosis is a highly conserved innate immune response.

scholarly journals Chronic Brucella Infection Induces Selective and Persistent Interferon Gamma-Dependent Alterations of Marginal Zone Macrophages in the Spleen

2017 ◽  
Vol 85 (11) ◽  
Author(s):  
Arnaud Machelart ◽  
Abir Khadrawi ◽  
Aurore Demars ◽  
Kevin Willemart ◽  
Carl De Trez ◽  
...  
Keyword(s):  
Interferon Gamma ◽  
Marginal Zone ◽  
Brucella Melitensis ◽  
Late Phase ◽  
Systemic Infection ◽  
Antigen Delivery ◽  
Content Type ◽  
Ifn Γ ◽  
Macrophage Populations ◽  
The Impact

ABSTRACTThe spleen is known as an important filter for blood-borne pathogens that are trapped by specialized macrophages in the marginal zone (MZ): the CD209+MZ macrophages (MZMs) and the CD169+marginal metallophilic macrophages (MMMs). Acute systemic infection strongly impacts MZ populations and the location of T and B lymphocytes. This phenomenon has been linked to reduced chemokine secretion by stromal cells.Brucellaspp. are the causative agent of brucellosis, a widespread zoonotic disease. Here, we usedBrucella melitensisinfection as a model to investigate the impact of chronic stealth infection on splenic MZ macrophage populations. During the late phase ofBrucellainfection, we observed a loss of both MZMs and MMMs, with a durable disappearance of MZMs, leading to a reduction of the ability of the spleen to take up soluble antigens, beads, and unrelated bacteria. This effect appears to be selective as every other lymphoid and myeloid population analyzed increased during infection, which was also observed followingBrucella abortusandBrucella suisinfection. Comparison of wild-type and deficient mice suggested that MZ macrophage population loss is dependent on interferon gamma (IFN-γ) receptor but independent of T cells or tumor necrosis factor alpha receptor 1 (TNF-αR1) signaling pathways and is not correlated to an alteration of CCL19, CCL21, and CXCL13 chemokine mRNA expression. Our results suggest that MZ macrophage populations are particularly sensitive to persistent low-level IFN-γ-mediated inflammation and thatBrucellainfection could reduce the ability of the spleen to perform certain MZM- and MMM-dependent tasks, such as antigen delivery to lymphocytes and control of systemic infection.

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