scholarly journals Genetically Modified Live Attenuated Leishmania donovani Parasites Induce Innate Immunity through Classical Activation of Macrophages That Direct the Th1 Response in Mice

2015 ◽  
Vol 83 (10) ◽  
pp. 3800-3815 ◽  
Author(s):  
Parna Bhattacharya ◽  
Ranadhir Dey ◽  
Pradeep K. Dagur ◽  
Michael Kruhlak ◽  
Nevien Ismail ◽  
...  

Visceral leishmaniasis (VL) causes significant mortality and there is no effective vaccine. Previously, we have shown that genetically modifiedLeishmania donovaniparasites, here described as live attenuated parasites, induce a host protective adaptive immune response in various animal models. In this study, we demonstrate an innate immune response upon infection with live attenuated parasites in macrophages from BALB/c mice bothin vitroandin vivo. In vitroinfection of macrophages with live attenuated parasites (compared to that with wild-type [WT]L. donovaniparasites) induced significantly higher production of proinflammatory cytokines (tumor necrosis factor alpha [TNF-α], interleukin-12 [IL-12], gamma interferon [IFN-γ], and IL-6), chemokines (monocyte chemoattractant protein 1/CCL-2, macrophage inflammatory protein 1α/CCL-3, and IP-10), reactive oxygen species (ROS), and nitric oxide, while concomitantly reducing anti-inflammatory cytokine IL-10 and arginase-1 activities, suggesting a dominant classically activated/M1 macrophage response. The classically activated response in turn helps in presenting antigen to T cells, as observed with robust CD4+T cell activationin vitro. Similarly, parasitized splenic macrophages from live attenuated parasite-infected mice also demonstrated induction of an M1 macrophage phenotype, indicated by upregulation of IL-1β, TNF-α, IL-12, and inducible nitric oxide synthase 2 and downregulation of genes associated with the M2 phenotype, i.e., the IL-10, YM1, Arg-1, and MRC-1 genes, compared to WTL. donovani-infected mice. Furthermore, anex vivoantigen presentation assay showed macrophages from live attenuated parasite-infected mice induced higher IFN-γ and IL-2 but significantly less IL-10 production by ovalbumin-specific CD4+T cells, resulting in proliferation of Th1 cells. These data suggest that infection with live attenuated parasites promotes a state of classical activation (M1 dominant) in macrophages that leads to the generation of protective Th1 responses in BALB/c mice.

Cells ◽  
2021 ◽  
Vol 10 (4) ◽  
pp. 868
Author(s):  
Fabiana Albani Zambuzi ◽  
Priscilla Mariane Cardoso-Silva ◽  
Ricardo Cardoso Castro ◽  
Caroline Fontanari ◽  
Flavio da Silva Emery ◽  
...  

Decitabine is an approved hypomethylating agent used for treating hematological malignancies. Although decitabine targets altered cells, epidrugs can trigger immunomodulatory effects, reinforcing the hypothesis of immunoregulation in treated patients. We therefore aimed to evaluate the impact of decitabine treatment on the phenotype and functions of monocytes and macrophages, which are pivotal cells of the innate immunity system. In vitro decitabine administration increased bacterial phagocytosis and IL-8 release, but impaired microbicidal activity of monocytes. In addition, during monocyte-to-macrophage differentiation, treatment promoted the M2-like profile, with increased expression of CD206 and ALOX15. Macrophages also demonstrated reduced infection control when exposed to Mycobacterium tuberculosis in vitro. However, cytokine production remained unchanged, indicating an atypical M2 macrophage. Furthermore, when macrophages were cocultured with lymphocytes, decitabine induced a reduction in the release of inflammatory cytokines such as IL-1β, TNF-α, and IFN-γ, maintaining IL-10 production, suggesting that decitabine could potentialize M2 polarization and might be considered as a therapeutic against the exacerbated immune response.


Blood ◽  
2019 ◽  
Vol 134 (Supplement_1) ◽  
pp. 5011-5011
Author(s):  
Haiping He ◽  
Atsuko Takahashi ◽  
Yuki Yamamoto ◽  
Akiko Hori ◽  
Yuta Miharu ◽  
...  

Background: Mesenchymal stromal cells (MSC) are known to have the immunosuppressive ability and have been applied in clinic to treat acute graft-versus-host disease (GVHD), as one of severe complications after hematopoietic stem cells transplantation (HSCT) in Japan. However, MSC are activated to suppress the immune system only upon the stimulation of inflammatory cytokines and the clinical results of MSC therapies for acute GVHD are varied. It is ideal that MSC are primed to be activated and ready to suppress the immunity (=priming) before administration in vivo. Triptolide (TPL) is a diterpene triepoxide purified from a Chinese herb - Tripterygium Wilfordii Hook F (TWHF). It has been shown to possess anti-inflammatory and immunosuppressive properties in vitro. In this study, we aim to use TPL as the activator for umbilical cord-derived MSC (UC-MSC) to entry stronger immunosuppressive status. Methods: The proliferation of UC-MSC with TPL at the indicated concentrations for different time of 24, 48, 72, and 96 hours. Cell counting kit-8(CCK-8) was added in the culture medium to detect cell toxicity and the absorbance was measured using microplate reader. Flow cytometry was used to identify the MSC surface markers expression. TPL-primed UC-MSC were once replaced with fresh medium and co-culture with mixed lymphocyte reaction (MLR) consisted with mononuclear cells (MNCs) stained with CFSE and irradiated allogenic dendritic cell line (PMDC05) in RPMI 1640 medium supplemented with 10 % FBS (complete medium). IDO-1, SOD1, and TGF-β gene expression in TPL-primed UC-MSC and UC-MSC induced by 10 ng/ml IFN-γ and/or 15 ng/ml TNF-α were evaluated by RT-PCR. PDL1 and PDL2 expression in TPL-primed UC-MSC and UC-MSC in response to IFN-γ and/or TNF-α were checked by Flowjo. Results: Exposure of TPL for UC-MSC for 72hour at the concentration above 0.1 μM resulted in the cell damage significantly. Therefore, we added TPL in UC-MSC at 0.01μM of TPL for up to 48 hours, then washed thourouphly for the following culture for experiments. To evaluate the influence of TPL on the surface markers of UC-MSC, we cultured UC-MSC for 4 hours in complete medium following culture with 0.01μM of TPL for 20 hours (TPL-primed UC-MSC). TPL-primed UC-MSC revealed positive for CD105, CD73, and CD90, negative for CD45, CD34, CD14 or CD11b, CD79α or CD19 and HLA-DR surface molecules as same as the non-primed UC-MSC. In MLR suppression by UC-MSC, the TPL-primed UC-MSC activity revealed stronger anti-proliferative effect on the CD4+ and CD8+ T cells activated by allogeneic DC than those of non-primed UC-MSC in MLR. Furthermore, the TPL-primed UC-MSC promoted the expression of IDO-1, SOD1 and TGF-β in response to IFN-γ+/-TNF-α by RT-PCR and enhanced the expression of PD-L1 by FACS analysis. Discussion:In this study, we found the TPL-primed UC-MSC showed stronger antiproliferative potency on CD4+ and CD8+ T cells compared with non-primed UC-MSC. TPL-primed UC-MSC promoted the expression of IDO-1, SOD1 and TGF-β stimulated by IFN-γ+/-TNF-α, although TPL alone did not induce these factors. Furthermore, we found that the PD1 ligand (PD-L1) was induced in TPL-primed UC-MSC, likely IFN-γ enhanced the PD-L1 expression, evaluated by flowcytometry. These results suggested that TPL-primed UC-MSC seemed more sensitive to be activated as the immunosuppressant. Here, we firstly report the new function of TPL to induce the upregulation of immunosuppressive effect, although the mechanisms of TPL inhibition to MSC need to be explore. Conclusively, TPL-primed UC-MSC might be applied for the immunosuppressive inducer of MSC. Figure Disclosures He: SASAGAWA Medical Scholarship: Research Funding; IMSUT Joint Research Project: Research Funding. Nagamura:AMED: Research Funding. Tojo:AMED: Research Funding; Torii Pharmaceutical: Research Funding. Nagamura-Inoue:AMED: Research Funding.


2017 ◽  
Vol 3 (2) ◽  
pp. 28
Author(s):  
Desie Dwi Wisudanti

Kefir is a functional foodstuff of probiotics, made from fermented milk with kefir grains containing various types of beneficial bacteria and yeast. There have been many studies on the effects of oral kefir on the immune system, but few studies have shown the effect of bioactive components from kefir (peptides and exopolysaccharides/ kefiran), on immune responses. The purpose of this study was to prove the effect of kefir supernatant from milk goat on healthy immune volunteer response in vitro. The study was conducted on 15 healthy volunteers, then isolated PBMC from whole blood, then divided into 5 groups (K-, P1, P2, P3 and P4) before culture was done for 4 days. The harvested cells from culture were examined for the percentage of CD4+ T cells, CD8+ T cells, IFN-γ, IL-4 using flowsitometry and IL-2 levels, IL-10 using the ELISA method. The results obtained that kefir do not affect the percentage of CD4+ T cells and CD8+ T cells. The higher the concentration of kefir given, the higher levels of secreted IFN- γ and IL-4, but a decrease in IL-2 levels. Significant enhancement occurred at levels of IL-10 culture PBMC given kefir with various concentrations (p <0.01), especially at concentrations of 1%. These results also show the important effects of kefir bioactive components on immune responses. The conclusion of this study is that kefir can improve the immune response, through stimulation of IL-10 secretion in vitro.


mSphere ◽  
2021 ◽  
Vol 6 (2) ◽  
Author(s):  
Jennifer H. Wilson-Welder ◽  
David P. Alt ◽  
Jarlath E. Nally ◽  
Steven C. Olsen

ABSTRACT This study examined the humoral and cellular response of cattle vaccinated with two commercial leptospiral vaccines, Leptavoid and Spirovac, and a novel bacterin vaccine using Seppic Montanide oil emulsion adjuvant. Vaccination was followed by experimental challenge. All vaccinated cattle were protected from colonization of the kidney and shedding of Leptospira in urine, as detected by culture and immunofluorescence assay. Agglutinating antibody titers were detected in vaccinated cattle at 4 weeks following vaccination, with small anamnestic response detected following experimental challenge. Only animals vaccinated with the oil emulsion-adjuvanted bacterin produced significant IgG2 titers following vaccination, and nonvaccinated animals produced serum IgA titers after experimental challenge. CD4+ and γδ T cells from vaccinated cattle proliferated when cultured with antigen ex vivo. Cellular responses included a marked proliferation of γδ T cells immediately following experimental challenge in vaccinated cattle and release of gamma interferon (IFN-γ), interleukin 17a (IL-17a), and IL-12p40 from stimulated cells. Proliferative and cytokine responses were found not just in peripheral mononuclear cells but also in lymphocytes isolated from renal lymph nodes at 10 weeks following experimental challenge. Overall, effects of leptospirosis vaccination and infection were subtle, resulting in only modest activation of CD4+ and γδ T cells. The use of Seppic Montanide oil emulsion adjuvants may shorten the initiation of response to vaccination, which could be useful during outbreaks or in areas where leptospirosis is endemic. IMPORTANCE Leptospirosis is an underdiagnosed, underreported zoonotic disease of which domestic livestock can be carriers. As a reservoir host for Leptospira borgpetersenii serovar Hardjo, cattle may present with reproductive issues, including abortion, birth of weak or infected calves, or failure to breed. Despite years of study and the availability of commercial vaccines, detailed analysis of the bovine immune response to vaccination and Leptospira challenge is lacking. This study evaluated immunologic responses to two efficacious commercial vaccines and a novel bacterin vaccine using an adjuvant chosen for enhanced cellular immune responses. Antigen-specific responsive CD4 and γδ T cells were detected following vaccination and were associated with release of inflammatory cytokines IFN-γ and IL-17a after stimulation. CD4 and γδ cells increased in the first week after infection and, combined with serum antibody, may play a role in clearance of bacteria from the blood and resident tissues. Additionally, these antigen-reactive T cells were found in the regional lymph nodes following infection, indicating that memory responses may not be circulating but are still present in regional lymph nodes. The information gained in this study expands knowledge of bovine immune response to leptospirosis vaccines and infection. The use of oil emulsion adjuvants may enhance early immune responses to leptospiral bacterins, which could be useful in outbreaks or situations where leptospirosis is endemic.


2015 ◽  
Vol 83 (8) ◽  
pp. 3074-3082 ◽  
Author(s):  
Nan Hou ◽  
Xianyu Piao ◽  
Shuai Liu ◽  
Chuang Wu ◽  
Qijun Chen

T cell immunoglobulin- and mucin-domain-containing molecule 3 (Tim-3) has been regarded as an important regulatory factor in both adaptive and innate immunity. Recently, Tim-3 was reported to be involved in Th2-biased immune responses in mice infected withSchistosoma japonicum, but the exact mechanism behind the involvement of Tim-3 remains unknown. The present study aims to understand the role of Tim-3 in the immune response againstS. japonicuminfection. Tim-3 expression was determined by flow cytometry, and increased Tim-3 expression was observed on CD4+and CD8+T cells, NK1.1+cells, and CD11b+cells from the livers ofS. japonicum-infected mice. However, the increased level of Tim-3 was lower in the spleen than in the liver, and no increase in Tim-3 expression was observed on splenic CD8+T cells or CD11b+cells. The schistosome-induced upregulation of Tim-3 on natural killer (NK) cells was accompanied by reduced NK cell numbersin vitroandin vivo. Tim-3 antibody blockade led to upregulation of inducible nitric oxide synthase and interleukin-12 (IL-12) mRNA in CD11b+cells cocultured with soluble egg antigen and downregulation of Arg1 and IL-10, which are markers of M2 macrophages. In summary, we observed schistosome-induced expression of Tim-3 on critical immune cell populations, which may be involved in the Th2-biased immune response and alternative activation of macrophages during infection.


2015 ◽  
Vol 83 (12) ◽  
pp. 4513-4527 ◽  
Author(s):  
Chrissy M. Leopold Wager ◽  
Camaron R. Hole ◽  
Karen L. Wozniak ◽  
Michal A. Olszewski ◽  
Mathias Mueller ◽  
...  

Cryptococcus neoformans, the predominant etiological agent of cryptococcosis, is an opportunistic fungal pathogen that primarily affects AIDS patients and patients undergoing immunosuppressive therapy. In immunocompromised individuals,C. neoformanscan lead to life-threatening meningoencephalitis. Studies using a virulent strain ofC. neoformansengineered to produce gamma interferon (IFN-γ), denoted H99γ, demonstrated that protection against pulmonaryC. neoformansinfection is associated with the generation of a T helper 1 (Th1)-type immune response and signal transducer and activator of transcription 1 (STAT1)-mediated classical (M1) macrophage activation. However, the critical mechanism by which M1 macrophages mediate their anti-C. neoformansactivity remains unknown. The current studies demonstrate that infection withC. neoformansstrain H99γ in mice with macrophage-specific STAT1 ablation resulted in severely increased inflammation of the pulmonary tissue, a dysregulated Th1/Th2-type immune response, increased fungal burden, deficient M1 macrophage activation, and loss of protection. STAT1-deficient macrophages produced significantly less nitric oxide (NO) than STAT1-sufficient macrophages, correlating with an inability to control intracellular cryptococcal proliferation, even in the presence of reactive oxygen species (ROS). Furthermore, macrophages from inducible nitric oxide synthase knockout mice, which had intact ROS production, were deficient in anticryptococcal activity. These data indicate that STAT1 activation within macrophages is required for M1 macrophage activation and anti-C. neoformansactivity via the production of NO.


2014 ◽  
Vol 82 (9) ◽  
pp. 3704-3712 ◽  
Author(s):  
Maria M. Figueiredo ◽  
Beatriz Deoti ◽  
Izabela F. Amorim ◽  
Aldair J. W. Pinto ◽  
Andrea Moraes ◽  
...  

ABSTRACTUsing flow cytometry, we evaluated the frequencies of CD4+and CD8+T cells and Foxp3+regulatory T cells (Tregs) in mononuclear cells in the jejunum, colon, and cervical and mesenteric lymph nodes of dogs naturally infected withLeishmania infantumand in uninfected controls. All infected dogs showed chronic lymphadenitis and enteritis. Despite persistent parasite loads, no erosion or ulcers were evident in the epithelial mucosa. The colon harbored more parasites than the jejunum. Frequencies of total CD4+, total Foxp3, and CD4+Foxp3+cells were higher in the jejunum than in the colon. Despite negative enzyme-linked immunosorbent assay (ELISA) serum results for cytokines, levels of interleukin-10 (IL-10), gamma interferon (IFN-γ), transforming growth factor beta (TGF-β), and tumor necrosis factor alpha (TNF-α) were higher in the jejunum than in the colon for infected dogs. However, IL-4 levels were higher in the colon than in the jejunum for infected dogs. There was no observed correlation between clinical signs and histopathological changes or immunological and parasitological findings in the gastrointestinal tract (GIT) of canines with visceral leishmaniasis. However, distinct segments of the GIT presented different immunological and parasitological responses. The jejunum showed a lower parasite load, with increased frequencies and expression of CD4, Foxp3, and CD8 receptors and IL-10, TGF-β, IFN-γ, and TNF-α cytokines. The colon showed a higher parasite load, with increasing expression of IL-4.Leishmania infantuminfection increased expression of CD4, Foxp3, IL-10, TGF-β, IFN-γ, and TNF-α and reduced CD8 and IL-4 expression in both the jejunum and the colon.


mBio ◽  
2020 ◽  
Vol 11 (2) ◽  
Author(s):  
Jennifer D. Helble ◽  
Rodrigo J. Gonzalez ◽  
Ulrich H. von Andrian ◽  
Michael N. Starnbach

ABSTRACT While there is no effective vaccine against Chlamydia trachomatis infection, previous work has demonstrated the importance of C. trachomatis-specific CD4+ T cells (NR1 T cells) in pathogen clearance. Specifically, NR1 T cells have been shown to be protective in mice, and this protection depends on the host’s ability to sense the cytokine gamma interferon (IFN-γ). However, it is unclear what role NR1 production or sensing of IFN-γ plays in T cell homing to the genital tract or T cell-mediated protection against C. trachomatis. Using two-photon microscopy and flow cytometry, we found that naive wild-type (WT), IFN-γ−/−, and IFN-γR−/− NR1 T cells specifically home to sections in the genital tract that contain C. trachomatis. We also determined that protection against infection requires production of IFN-γ from either NR1 T cells or endogenous cells, further highlighting the importance of IFN-γ in clearing C. trachomatis infection. IMPORTANCE Chlamydia trachomatis is an important mucosal pathogen that is the leading cause of sexually transmitted bacterial infections in the United States. Despite this, there is no vaccine currently available. In order to develop such a vaccine, it is necessary to understand the components of the immune response that can lead to protection against this pathogen. It is well known that antigen-specific CD4+ T cells are critical for Chlamydia clearance, but the contexts in which they are protective or not protective are unknown. Here, we aimed to characterize the importance of gamma interferon production and sensing by T cells and the effects on the immune response to C. trachomatis. Our work here helps to define the contexts in which antigen-specific T cells can be protective, which is critical to our ability to design an effective and protective vaccine against C. trachomatis.


2011 ◽  
Vol 79 (10) ◽  
pp. 3940-3946 ◽  
Author(s):  
Cuixia Shi ◽  
Bikash Sahay ◽  
Jennifer Q. Russell ◽  
Karen A. Fortner ◽  
Nicholas Hardin ◽  
...  

ABSTRACTLittle is known regarding the function of γδ T cells, although they accumulate at sites of inflammation in infections and autoimmune disorders. We previously observed that γδ T cellsin vitroare activated byBorrelia burgdorferiin a TLR2-dependent manner. We now observe that the activated γδ T cells can in turn stimulate dendritic cellsin vitroto produce cytokines and chemokines that are important for the adaptive immune response. This suggested thatin vivoγδ T cells may assist in activating the adaptive immune response. We examined this possibilityin vivoand observed that γδ T cells are activated and expand in number duringBorreliainfection, and this was reduced in the absence of TLR2. Furthermore, in the absence of γδ T cells, there was a significantly blunted response of adaptive immunity, as reflected in reduced expansion of T and B cells and reduced serum levels of anti-Borreliaantibodies, cytokines, and chemokines. This paralleled a greaterBorreliaburden in γδ-deficient mice as well as more cardiac inflammation. These findings are consistent with a model of γδ T cells functioning to promote the adaptive immune response during infection.


2015 ◽  
Vol 83 (5) ◽  
pp. 2118-2126 ◽  
Author(s):  
Truc Hoang ◽  
Else Marie Agger ◽  
Joseph P. Cassidy ◽  
Jan P. Christensen ◽  
Peter Andersen

Protein energy malnutrition (PEM) increases susceptibility to infectious diseases, including tuberculosis (TB), but it is not clear how PEM influences vaccine-promoted immunity to TB. We demonstrate that PEM during low-level steady-state TB infection in a mouse model results in rapid relapse ofMycobacterium tuberculosis, as well as increased pathology, in bothMycobacterium bovisBCG-vaccinated and unvaccinated animals. PEM did not change the overall numbers of CD4 T cells in BCG-vaccinated animals but resulted in an almost complete loss of antigen-specific cytokine production. Furthermore, there was a change in cytokine expression characterized by a gradual loss of multifunctional antigen-specific CD4 T cells and an increased proportion of effector cells expressing gamma interferon and tumor necrosis factor alpha (IFN-γ+TNF-α+and IFN-γ+cells). PEM duringM. tuberculosisinfection completely blocked the protection afforded by the H56-CAF01 subunit vaccine, and this was associated with a very substantial loss of the interleukin-2-positive memory CD4 T cells promoted by this vaccine. Similarly, PEM during the vaccination phase markedly reduced the H56-CAF01 vaccine response, influencing all cytokine-producing CD4 T cell subsets, with the exception of CD4 T cells positive for TNF-α only. Importantly, this impairment was reversible and resupplementation of protein during infection rescued both the vaccine-promoted T cell response and the protective effect of the vaccine againstM. tuberculosisinfection.


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