scholarly journals Chronic Aerobic Training at Different Volumes in the Modulation of Macrophage Function and in vivo Infection of BALB/c Mice by Leishmania major

2021 ◽  
Vol 12 ◽  
Author(s):  
T. T. Guimarães ◽  
S. M. R. Gomes ◽  
R. A. A. C. Albuquerque ◽  
A. K. C. Lima ◽  
G. F. Braga ◽  
...  
Keyword(s):  
Leishmania Major ◽  
Aerobic Training ◽  
Clinical Manifestations ◽  
High Volume ◽  
Strenuous Exercise ◽  
Macrophage Infection ◽  
Th2 Response ◽  
Th1 Response ◽  
Very High

Physical inactivity is one of the main causes of chronic diseases; however, strenuous exercise can induce immunosuppression. Several studies suggest that moderate amounts of exercise lead to a Th1 response, favoring the resolution of infections caused by intracellular microorganisms, while high volumes of exercise tend to direct the response to Th2, favoring infection by them. Leishmaniasis is a parasitic disease promoted by parasites of the Leishmania genus, with clinical manifestations that vary according to the species of the parasite and the immune response of the host. The experimental Leishmania major–BALB/C mouse model provides a good model for the resistance (Th1 response) or susceptibility (Th2 response) that determines the progression of this infection. The aim of this study was to evaluate the effect of aerobic training at different volumes on modulation of in vitro macrophage infection by L. major, as well as to assess the effect of high volume (HV) aerobic training on the development of L. major in vivo in BALB/c mice. Uninfected animals were submitted to various exercise volumes: none (SED), light (LV), moderate (MV), high (HV), very high (VHV), and tapering (TAP). The macrophages of these animals were infected by L. major and the LV and MV groups showed a decrease in the infection factor, while the VHV showed an increase in the infection factor, when treated with LPS. The cytokine concentration pattern measured in the supernatants of these macrophages suggested a predominant Th1 response profile in the LV and MV groups, while the Th2 profile predominated in the VHV and TAP groups. Groups of BALB/C mice infected with L. major were subjected to high volume (iHV) or non-periodized high volume (iNPHV) exercise or kept sedentary (iSED). The exercised animals suffered a significant increase in injuries caused by the parasites. The animals in the group submitted to high volume exercise (iHV) showed visceralization of the infection. These data strongly suggest that a very high volume of aerobic training increased the susceptibility of BALB/C mice to L. major infection, while moderate distribution of training loads promoted immunological balance, better controlling the infection by this parasite.

scholarly journals Early Enhanced Th1 Response after Leishmania amazonensis Infection of C57BL/6 Interleukin-10-Deficient Mice Does Not Lead to Resolution of Infection

2002 ◽  
Vol 70 (4) ◽  
pp. 2151-2158 ◽  
Author(s):  
Douglas E. Jones ◽  
Mark R. Ackermann ◽  
Ulrike Wille ◽  
Christopher A. Hunter ◽  
Phillip Scott
Keyword(s):  
Leishmania Major ◽  
Chronic Phase ◽  
Leishmania Amazonensis ◽  
Delayed Type Hypersensitivity ◽  
Cell Mediated Immunity ◽  
Th2 Response ◽  
Th1 Response ◽  
Response Expression ◽  
Deficient Mice

ABSTRACT C3H and C57BL/6 mice are resistant to Leishmania major but develop chronic lesions with persistent parasite loads when they are infected with Leishmania amazonensis. These lesions develop in the absence of interleukin-4 (IL-4), indicating that susceptibility to this parasite is not a result of development of a Th2 response. Expression of the cytokine IL-10 during infection could account for the lack of IL-12 expression and poor cell-mediated immunity towards the parasite. Therefore, we tested the hypothesis that IL-10 plays a central role in downmodulating the Th1 response after L. amazonensis infection. Infection of C57BL/6 IL-10-deficient mice indicated that in the absence of IL-10 there was early enhancement of a Th1 response, which was downregulated during the more chronic stage of infection. In addition, although there were 1- to 2-log reductions in the parasite loads within the lesions, the parasites continued to persist, and they were associated with chronic lesions whose size was similar to that of the control lesions. These experiments indicated that L. amazonensis resistance to killing in vivo is only partially dependent on expression of host IL-10. However, IL-10-deficient mice had an enhanced delayed-type hypersensitivity response during the chronic phase of infection, indicating that there were Th1 type effector cells in vivo at this late stage of infection. These results indicate that although IL-10 plays a role in limiting the Th1 response during the acute infection phase, other immunomodulatory factors are responsible for limiting the Th1 response during the chronic phase.

scholarly journals Low Dose Leishmania major Promotes a Transient T Helper Cell Type 2 Response That Is Down-regulated by Interferon γ–producing CD8+ T Cells

2004 ◽  
Vol 199 (11) ◽  
pp. 1559-1566 ◽  
Author(s):  
Jude E. Uzonna ◽  
Karen L. Joyce ◽  
Phillip Scott
Keyword(s):  
T Cells ◽  
Cd8 T Cells ◽  
Low Dose ◽  
Leishmania Major ◽  
Interferon Γ ◽  
Th2 Response ◽  
Th1 Response ◽  
Th Cell

An unresolved issue in the field of T helper (Th) cell development relates to the findings that low doses of antigen promote Th2 cell development in vitro, whereas several classic in vivo studies suggest the opposite. Here we resolve this paradox by studying the early immune response in mice after infection with different doses of Leishmania major. We found that low parasite doses induced a Th2 response in C57BL/6 (B6) mice, whereas high doses induced a Th1 response. However, the Th2 response in low dose–infected mice was transient and the animals healed. The appearance of a Th1 response after low dose infection was dependent upon the concomitant activation of interferon γ–producing CD8+ T cells. In the absence of CD8+ T cells, the Th2 response was maintained. However, either neutralization of interleukin (IL)-4 or administration of IL-12 promoted a Th1 response after low dose infection of CD8-deficient mice, indicating that the required role for CD8+ T cells was limited to modulation of CD4+ T cell responses. Thus, the discrepant results seen between in vivo and in vitro studies on the effects of antigen dose on Th cell differentiation may depend upon whether CD8+ T cells participate in the immune response.

scholarly journals Polarized Helper-T-Cell Responses againstLeishmania major in the Absence of B Cells

1999 ◽  
Vol 67 (1) ◽  
pp. 266-270 ◽  
Author(s):  
Daniel R. Brown ◽  
Steven L. Reiner
Keyword(s):  
T Cell ◽  
B Cells ◽  
Leishmania Major ◽  
Immunoglobulin M ◽  
Wild Type ◽  
Th2 Response ◽  
Th1 Response ◽  
Cell Responses ◽  
Th Cell ◽  
Th2 Responses

ABSTRACT B-cell-to-T-cell signaling can shape helper T (Th) cell responses. During infection with Leishmania major, Th response is critical in determining the outcome of disease. Resistance depends on the generation of a protective Th1 response, while susceptibility is mediated by the generation of a Th2 response. In this study, we determined whether B cells are required for the development of polarized Th1 and Th2 responses during infection with L. major. Mice lacking B cells due to disruption of the immunoglobulin M locus (μMT) were infected with L. major, and disease progression and Th cell development were assessed. On the genetically resistant C57BL background, both wild-type and μMT mice controlled the infection and mounted a Th1 response. On the genetically susceptible BALB/c background, both wild-type and μMT mice were susceptible to infection and generated Th2 responses. Thus, duringL. major infection, neither direct antigen presentation or costimulation by B cells nor antibody-mediated effector functions are essential for the development of polarized Th responses.

scholarly journals Development of a New Antileishmanial Aziridine-2,3-Dicarboxylate-Based Inhibitor with High Selectivity for Parasite Cysteine Proteases

2015 ◽  
Vol 60 (2) ◽  
pp. 797-805 ◽  
Author(s):  
Caroline Schad ◽  
Ulrike Baum ◽  
Benjamin Frank ◽  
Uwe Dietzel ◽  
Felix Mattern ◽  
...  
Keyword(s):  
Leishmania Major ◽  
Neglected Tropical Diseases ◽  
Cathepsin L ◽  
Selective Inhibition ◽  
Cysteine Proteases ◽  
Host Cells ◽  
Th2 Response ◽  
Content Type

ABSTRACTLeishmaniasis is one of the major neglected tropical diseases of the world. Druggable targets are the parasite cysteine proteases (CPs) of clan CA, family C1 (CAC1). In previous studies, we identified two peptidomimetic compounds, the aziridine-2,3-dicarboxylate compounds 13b and 13e, in a series of inhibitors of the cathepsin L (CL) subfamily of the papain clan CAC1. Both displayed antileishmanial activityin vitrowhile not showing cytotoxicity against host cells. In further investigations, the mode of action was characterized inLeishmania major. It was demonstrated that aziridines 13b and 13e mainly inhibited the parasitic cathepsin B (CB)-like CPC enzyme and, additionally, mammalian CL. Although these compounds induced cell death ofLeishmaniapromastigotes and amastigotesin vitro, the induction of a proleishmanial T helper type 2 (Th2) response caused by host CL inhibition was observedin vivo. Therefore, we describe here the synthesis of a new library of more selective peptidomimetic aziridine-2,3-dicarboxylates discriminating between host and parasite CPs. The new compounds are based on 13b and 13e as lead structures. One of the most promising compounds of this series is compound s9, showing selective inhibition of the parasite CPsLmaCatB (a CB-like enzyme ofL. major; also namedL. majorCPC) andLmCPB2.8 (a CL-like enzyme ofLeishmania mexicana) while not affecting mammalian CL and CB. It displayed excellent leishmanicidal activities againstL. majorpromastigotes (50% inhibitory concentration [IC50] = 37.4 μM) and amastigotes (IC50= 2.3 μM). In summary, we demonstrate a new selective aziridine-2,3-dicarboxylate, compound s9, which might be a good candidate for futurein vivostudies.

scholarly journals Immunization with a Toll-Like Receptor 7 and/or 8 Agonist Vaccine Adjuvant Increases Protective Immunity against Leishmania major in BALB/c Mice

2008 ◽  
Vol 76 (8) ◽  
pp. 3777-3783 ◽  
Author(s):  
Wen-Wei Zhang ◽  
Greg Matlashewski
Keyword(s):  
Protective Immunity ◽  
Leishmania Major ◽  
Challenge Infection ◽  
Innate Immune ◽  
Infection Model ◽  
Vaccine Adjuvants ◽  
Th2 Response ◽  
Th1 Response ◽  
Potential Vaccine ◽  
Antigen Presenting

ABSTRACT Activation of Toll-like receptors (TLRs) on antigen-presenting cells of the innate immune system initiates, amplifies, and directs the antigen-specific acquired immune response. Ligands that stimulate TLRs therefore represent potential vaccine adjuvants. In the present study, we determined whether imiquimod and its related compound R848, which are TLR7 and/or TLR8 agonists, represent potential vaccine adjuvants when delivered topically, subcutaneously, or intramuscularly. Using the Leishmania major infection model in BALB/c mice, vaccination with crude Leishmania antigen was not protective against subsequent challenge infection unless it was administered with R848 or a topical application of imiquimod containing cream on the skin. Subcutaneous vaccination with these adjuvants mediated a TH1 response against L. major antigen, which appeared to suppress the TH2 response following a challenge infection. Protective immunity was generated following subcutaneous vaccination but not intramuscular vaccination. These observations suggest that topically administered imiquimod or subcutaneously injected R848 represent potential vaccine adjuvants to enhance the TH1 response, which can be used with existing or new vaccine formulations.

scholarly journals Combined Treatment with Interleukin-12 and Indomethacin Promotes Increased Resistance in BALB/c Mice with Established Leishmania major Infections

2002 ◽  
Vol 70 (10) ◽  
pp. 5715-5720 ◽  
Author(s):  
Jian Li ◽  
Udaikumar M. Padigel ◽  
Phillip Scott ◽  
Jay P. Farrell
Keyword(s):  
Leishmania Major ◽  
Combined Treatment ◽  
Interleukin 4 ◽  
Th2 Cells ◽  
Interleukin 12 ◽  
Th2 Response ◽  
Enhanced Production ◽  
Time Of Infection

ABSTRACT Following infection of susceptible BALB/c mice with Leishmania major, early production of interleukin-4 (IL-4) is associated with the development of a nonprotective Th2 response and the development of progressive disease. Treatment of mice with IL-12 at the time of infection can promote the activation of a protective Th1 response; however, IL-12 treatment of mice with established infections has little effect on the progress of lesion development. This may be due to a down-regulation of the IL-12 receptor β2 chain (IL-12Rβ2) that accompanies the expansion of IL-4-producing Th2 cells. We have examined whether prostaglandins function to regulate in vivo responsiveness to IL-12. Mice treated with indomethacin are responsive to treatment with exogenous IL-12 through at least the first 2 weeks of infection and, unlike control mice treated with IL-12, develop an enhanced Th1-type response associated with increased enhanced resistance to infection. Cells from indomethacin-treated mice also exhibit enhanced production of gamma interferon (IFN-γ) following in vitro stimulation with IL-12. Although in vivo indomethacin treatment did not appear to influence IL-12 production in infected mice, cells from indomethacin-treated mice did express higher levels of IL-12Rβ2, suggesting that prostaglandins may play a role in the loss of IL-12 responsiveness observed during nonhealing L. major infections.

scholarly journals Interleukin-12 Is Capable of Generating an Antigen-Specific Th1-Type Response in the Presence of an Ongoing Infection-Driven Th2-Type Response

1999 ◽  
Vol 67 (5) ◽  
pp. 2166-2171 ◽  
Author(s):  
Lisa R. Schopf ◽  
Judy L. Bliss ◽  
Liz M. Lavigne ◽  
Charles L. Chung ◽  
Stanley F. Wolf ◽  
...  
Keyword(s):  
Leishmania Major ◽  
Keyhole Limpet Hemocyanin ◽  
Interleukin 12 ◽  
Th2 Response ◽  
Th1 Response ◽  
Specific Immunoglobulin ◽  
Ifn Γ ◽  
Type Response ◽  
Visceral Disease ◽  
Ongoing Infection

ABSTRACT Previously we demonstrated that recombinant murine interleukin-12 (rmIL-12) administration can promote a primary Th1 response while suppressing the Th2 response in mice primed with 2,4,6-trinitrophenyl–keyhole limpet hemocyanin (TNP-KLH). The present studies examined the capacity of rmIL-12 to drive a Th1 response to TNP-KLH in the presence of an ongoing Th2-mediated disease. To establish a distinct Th2 response, we used a murine model of leishmaniasis. Susceptible BALB/c mice produce a strong Th2 response when infected with Leishmania major and develop progressive visceral disease. On day 26 postinfection, when leishmaniasis was well established, groups of mice were immunized with TNP-KLH in the presence or absence of exogenous rmIL-12. Even in the presence of overt infection, TNP-KLH-plus-rmIL-12-immunized mice were still capable of generating KLH-specific gamma interferon (IFN-γ) as well as corresponding TNP-specific immunoglobulin G2a (IgG2a) titers. In addition, the KLH-specific IL-4 was suppressed in infected mice immunized with rmIL-12. However, parasite-specific IL-4 and IgG1 production with a lack of parasite-specific IFN-γ secretion were maintained in all infected groups of mice including those immunized with rmIL-12. These data show that despite the ongoing infection-driven Th2 response, rmIL-12 was capable of generating an antigen-specific Th1 response to an independent immunogen. Moreover, rmIL-12 administered with TNP-KLH late in infection did not alter the parasite-specific cytokine or antibody responses.

scholarly journals Expression of Multiple CPB Genes Encoding Cysteine Proteases Is Required for Leishmania mexicana Virulence In Vivo

2003 ◽  
Vol 71 (6) ◽  
pp. 3190-3195 ◽  
Author(s):  
Hubert Denise ◽  
Kathryn McNeil ◽  
Darren R. Brooks ◽  
James Alexander ◽  
Graham H. Coombs ◽  
...  
Keyword(s):  
Gene Array ◽  
Cysteine Proteases ◽  
Parasite Growth ◽  
Interleukin 4 ◽  
Leishmania Mexicana ◽  
Th2 Response ◽  
Th1 Response ◽  
Genes Encoding ◽  
Lesion Growth

ABSTRACT Leishmania mexicana mutants deficient in the multicopy CPB gene array have reduced virulence, demonstrated by poor lesion growth in BALB/c mice and induction of a protective Th1 response. Reinsertion of the amastigote-specific CPB2.8 or metacyclic stage-specific CPB2 gene into a CPB-deficient mutant L. mexicana failed to restore either a Th2 response or sustained virulence. However, reexpression of multiple CPB genes from a cosmid significantly restored virulence. This was characterized by increased lesion and parasite growth and the acquisition of a Th2 response, as determined by measuring interleukin-4 production and immunoglobulin G1 (IgG1) and IgE levels. These studies confirm that L. mexicana cysteine proteases are important virulence factors and provide an explanation for the presence in L. mexicana of a multicopy tandem array of CPB genes.

Interleukin-18 attracts plasmacytoid dendritic cells (DC2s) and promotes Th1 induction by DC2s through IL-18 receptor expression

Blood ◽  
2004 ◽  
Vol 103 (2) ◽  
pp. 648-655 ◽  
Author(s):  
Arthur Kaser ◽  
Susanne Kaser ◽  
Nicole C. Kaneider ◽  
Barbara Enrich ◽  
Christian J. Wiedermann ◽  
...  
Keyword(s):  
Dendritic Cells ◽  
Receptor Expression ◽  
Interleukin 18 ◽  
Th2 Response ◽  
Th1 Response ◽  
Initiation Phase ◽  
Helper Cell Type

Abstract In vivo evidence suggests that interleukin-18 (IL-18) shapes the development of adaptive immunity toward T-helper cell type 1 (Th1) responses. Monocyte-derived dendritic cells 1 (DC1s) preferentially induce a Th1 response, while plasmacytoid DC-derived DC2s have been linked to a Th2 response. We analyzed the role of IL-18 during the initiation phase of a Th response in vitro to elucidate the basis of these in vivo observations. IL-18 was constitutively released from DC1s, but not DC2s. Neutralization of IL-18 in coculture experiments of DC1s with allogeneic naive T lymphocytes did not alter the Th1/Th2 phenotype, while anti–IL-12 efficiently down-regulated the Th1 response. Unexpectedly, IL-18 receptor (IL-18R) α and β chains were expressed on DC2 lineage. IL-18R expression was functional, as IL-18 induced chemotaxis in plasmacytoid DCs (pre-DC2s) and enhanced the allostimulatory capacity of IL-3–differentiated DC2s. Pre-DC2s exposed to IL-18 skewed the development of Th cells toward Th1 in coculture experiments of DC2s and allogeneic naive T cells, which was inhibited by IL-12 p70 neutralization. IL-18 might have a profound role during the initiation phase of an immune response by recruiting pre-DC2s and modulating the function of DC2s.

scholarly journals Heterologous Expression of Trypanosoma cruzi trans-Sialidase in Leishmania major Enhances Virulence

2000 ◽  
Vol 68 (5) ◽  
pp. 2728-2734 ◽  
Author(s):  
M. Belen Carrillo ◽  
Wenda Gao ◽  
Macario Herrera ◽  
Joseph Alroy ◽  
Jeffrey B. Moore ◽  
...  
Keyword(s):  
Trypanosoma Cruzi ◽  
Heterologous Expression ◽  
Leishmania Major ◽  
Protozoan Parasite ◽  
Macrophage Infection ◽  
Cutaneous Lesions ◽  
New Approach ◽  
Extracellular Milieu ◽  
Expression Construct

ABSTRACT Earlier studies showed that mice primed for a few hours with thetrans-sialidase (TS) of Trypanosoma cruzi, the agent of Chagas' disease, become highly susceptible to trypanosomal infection. These studies suggest that TS affects parasite virulence independent of antigenic stimulation. Potentially, TS could enhance or reduce the virulence of heterologous microbes depending on the mechanism of TS action and on the type of immune response elicited by the particular parasite. We tested this hypothesis by expressing heterologous TS in Leishmania major, a protozoan parasite that causes cutaneous leishmaniasis and lacks TS and the TS product α2-3-linked sialic acid. Leishmania cells transfected with a T. cruzi TS expression construct made high levels of active enzyme, which was present in the promastigotes and shed into the extracellular milieu. TS expression did not affect L. majorbinding to and entry into cultured macrophages or its tropism for macrophage infection in vivo. However, TS-expressing L. major exhibited elevated virulence in BALB/c mice, as determined by lesion progression, parasite numbers, and macro- and microscopic examination of cutaneous lesions. Several genetic tests proved that the enhanced virulence was directly attributable to TS expression. The results are consistent with TS functioning to sabotage the mouse immune system to confer a growth advantage on T. cruzi and transgenic L. major. These data suggest that heterologous expression of T. cruzi virulence factors inLeishmania may provide a new approach for dissecting their function in vivo.

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