scholarly journals Parasite load, iNOS and cytokine profiles, and histopathological aspects of Leishmania infantum infection in dogs with different clinical presentations

2019 ◽  
Vol 49 (10) ◽  
Author(s):  
Tassia Cristina Bello de Vasconcelos ◽  
Sávio Freire Bruno ◽  
Luisa Helena Monteiro de Miranda ◽  
Fátima Conceição-Silva ◽  
Vinícius Silva Belo ◽  
...  
Keyword(s):  
Leishmania Infantum ◽  
Clinical Symptoms ◽  
Immunological Response ◽  
Parasite Load ◽  
Hepatic Tissue ◽  
Inos Mrna ◽  
White Pulp ◽  
Clinical Presentations ◽  
Ifn Γ

ABSTRACT: Visceral leishmaniasis (VL) is a zoonotic disease with a canine urban reservoir in South America. Dogs from an endemic area within Brazil, which were naturally infected with Leishmania infantum, and those presenting severe clinical (SC), mild, or no clinical (MNC) disease, were evaluated. Parasite load, histopathology, and cytokine and iNOS mRNA expressions were assessed in the spleen and liver in order to determine the potential markers for disease susceptibility or resistance. As a result, dogs with both SC and MNC had high parasite loads; IFN-γ was the most expressive cytokine in both organs, along with IL-6 and IL-4 being detected in the spleen and liver, and IL-10 only in liver. The hepatic tissue presented higher medians for IFN-γ and IL-10, and was the main organ to produce cytokines with hepatic IL-10 suggesting a regulatory follow up. Granulomas were detected in both organs; however, when absent in spleen, they were associated with elevated IL-6 levels, thus highlighting the anti-inflammatory role of IL-6. Microscopic lesions in the spleen were predominantly characterized by an extensively disorganized white pulp and splenic response was suggested as sub optimized. Parasite load, tissue damage, and immunological response may vary in the dogs with similar clinical symptoms, which may not be a good parameter for assessing the animal’s susceptibility to VL.

scholarly journals Vaccination with the Leishmania infantum Acidic Ribosomal P0 Protein plus CpG Oligodeoxynucleotides Induces Protection against Cutaneous Leishmaniasis in C57BL/6 Mice but Does Not Prevent Progressive Disease in BALB/c Mice

2005 ◽  
Vol 73 (9) ◽  
pp. 5842-5852 ◽  
Author(s):  
Salvador Iborra ◽  
Javier Carrión ◽  
Charles Anderson ◽  
Carlos Alonso ◽  
David Sacks ◽  
...  
Keyword(s):  
Cutaneous Leishmaniasis ◽  
Leishmania Infantum ◽  
Progressive Disease ◽  
Immunological Response ◽  
Parasite Load ◽  
Th2 Response ◽  
Suitable Alternative ◽  
Cpg Oligodeoxynucleotides ◽  
Potential Efficacy ◽  
Ifn Γ

ABSTRACT We have examined the efficacy of the administration in mice of a molecularly defined vaccine based on the Leishmania infantum acidic ribosomal protein P0 (rLiP0). Two different challenge models of murine cutaneous leishmaniasis were used: (i) subcutaneous inoculation of L. major parasites in susceptible BALB/c mice (a model widely used for vaccination analysis) and (ii) the intradermal inoculation of a low infective dose in resistant C57BL/6 mice (a model that more accurately reproduces the L. major infection in natural reservoirs and in human hosts). First, we demonstrated that C57BL/6 mice vaccinated with LiP0-DNA or rLiP0 protein plus CpG oligodeoxynucleotides (ODN) were protected against the development of dermal pathology and showed a reduction in the parasite load. This protection was associated with production of gamma interferon (IFN-γ) in the dermal site. Secondly, we showed that immunization with rLiP0 plus CpG ODN is able to induce only partial protection in BALB/c, since these mice finally developed a progressive disease. Further, we demonstrated that LiP0 vaccination induces a Th1 immunological response in both strains of mice. In both cases, the antibodies against LiP0 were predominantly of the immunoglobulin G2a isotype, which was correlated with an rLiP0-stimulated production of IFN-γ in draining lymph nodes. Finally, we demonstrated that LiP0 vaccination does not prevent the Th2 response induced by L. major infection in BALB/c mice. Taken together, these data indicate that the BALB/c model of cutaneous leishmaniasis may undervalue the potential efficacy of some vaccines based on defined proteins, making C57BL/6 a suitable alternative model to test vaccine candidates.

scholarly journals Absence of Bim sensitizes mice to experimental Trypanosoma cruzi infection

2021 ◽  
Vol 12 (7) ◽  
Author(s):  
Marcela Hernández-Torres ◽  
Rogério Silva do Nascimento ◽  
Monica Cardozo Rebouças ◽  
Alexandra Cassado ◽  
Kely Catarine Matteucci ◽  
...  
Keyword(s):  
T Cells ◽  
Trypanosoma Cruzi ◽  
Chagas Disease ◽  
Parasite Load ◽  
Peritoneal Macrophages ◽  
T Cell Response ◽  
No Production ◽  
Similar Reduction ◽  
Ifn Γ

AbstractChagas disease is a life-threatening disorder caused by the protozoan parasite Trypanosoma cruzi. Parasite-specific antibodies, CD8+ T cells, as well as IFN-γ and nitric oxide (NO) are key elements of the adaptive and innate immunity against the extracellular and intracellular forms of the parasite. Bim is a potent pro-apoptotic member of the Bcl-2 family implicated in different aspects of the immune regulation, such as negative selection of self-reactive thymocytes and elimination of antigen-specific T cells at the end of an immune response. Interestingly, the role of Bim during infections remains largely unidentified. To explore the role of Bim in Chagas disease, we infected WT, Bim+/−, Bim−/− mice with trypomastigotes forms of the Y strain of T. cruzi. Strikingly, our data revealed that Bim−/− mice exhibit a delay in the development of parasitemia followed by a deficiency in the control of parasite load in the bloodstream and a decreased survival compared to WT and Bim+/− mice. At the peak of parasitemia, peritoneal macrophages of Bim−/− mice exhibit decreased NO production, which correlated with a decrease in the pro-inflammatory Small Peritoneal Macrophage (SPM) subset. A similar reduction in NO secretion, as well as in the pro-inflammatory cytokines IFN-γ and IL-6, was also observed in Bim−/− splenocytes. Moreover, an impaired anti-T. cruzi CD8+ T-cell response was found in Bim−/− mice at this time point. Taken together, our results suggest that these alterations may contribute to the establishment of a delayed yet enlarged parasitic load observed at day 9 after infection of Bim−/− mice and place Bim as an important protein in the control of T. cruzi infections.

scholarly journals The Leishmania infantum Acidic Ribosomal Protein P0 Administered as a DNA Vaccine Confers Protective Immunity to Leishmania major Infection in BALB/c Mice

2003 ◽  
Vol 71 (11) ◽  
pp. 6562-6572 ◽  
Author(s):  
Salvador Iborra ◽  
Manuel Soto ◽  
Javier Carrión ◽  
Ana Nieto ◽  
Edgar Fernández ◽  
...  
Keyword(s):  
Ribosomal Protein ◽  
Leishmania Infantum ◽  
Leishmania Major ◽  
Parasite Burden ◽  
Immunological Response ◽  
Humoral Response ◽  
Ifn Γ ◽  
Immunogenic Properties ◽  
Ribosomal Protein P0 ◽  
Acidic Ribosomal Protein

ABSTRACT In this study, we examined the immunogenic properties of the Leishmania infantum acidic ribosomal protein P0 (LiP0) in the BALB/c mouse model. The humoral and cellular responses induced by the administration of the LiP0 antigen, either as soluble recombinant LiP0 (rLiP0) or as a plasmid DNA formulation (pcDNA3-LiP0), were determined. Also, the immunological response associated with a prime-boost strategy, consisting of immunization with pcDNA3-LiP0 followed by a boost with rLiP0, was assayed. Immunization with rLiP0 induced a predominant Th2-like humoral response, but no anti-LiP0 antibodies were induced after immunization with pcDNA3-LiP0, whereas a strong humoral response consisting of a mixed immunoglobulin G2a (IgG2a)-IgG1 isotype profile was induced in mice immunized with the prime-boost regime. For all three immunization protocols, rLiP0-stimulated production of gamma interferon (IFN-γ) in both splenocytes and lymph node cells from immunized mice was observed. However, it was only when mice were immunized with pcDNA3-LiP0 that noticeable protection against L. major infection was achieved, as determined by both lesion development and parasite burden. Immunization of mice with LiP0-DNA primes both CD4+ and CD8+ T cells, which, with the L. major challenge, were boosted to produce significant levels of IL-12-dependent, antigen-specific IFN-γ. Taken together, these data indicate that genetic vaccination with LiP0 induces protective immunological effector mechanisms, yet the immunological response elicited by LiP0 is not sufficient to keep the infection from progressing.

scholarly journals Role of Gamma Interferon in Helicobacter pylori Induction of Inflammatory Mediators during Murine Infection

2002 ◽  
Vol 70 (6) ◽  
pp. 3295-3299 ◽  
Author(s):  
Marygorret Obonyo ◽  
Donald G. Guiney ◽  
Julia Harwood ◽  
Joshua Fierer ◽  
Sheri P. Cole
Keyword(s):  
Helicobacter Pylori ◽  
Gene Knockout ◽  
Gamma Interferon ◽  
Epithelial Cell Line ◽  
Inos Mrna ◽  
Inflammatory Protein ◽  
Ifn Γ ◽  
H Pylori ◽  
Oxide Synthase

ABSTRACT Gamma interferon (IFN-γ) has been proposed to play an important role in Helicobacter-related gastritis. Using the IFN-γ gene knockout (IFN-γ−/−) mouse model and a murine gastric epithelial cell line, GSM06, we demonstrated that Helicobacter pylori maximally induced macrophage inflammatory protein-2 (MIP-2) and inducible nitric oxide synthase (iNOS) mRNA only in wild-type mice. MIP-2 and iNOS mRNA were also induced by H. pylori in GSM06 cells. Induction of cyclooxygenase 2 mRNA through IFN-γ was demonstrated in GSM06 cells. These data indicate that IFN-γ mediates the induction of MIP-2 and iNOS mRNA expression by H. pylori in mice.

scholarly journals Expression of Regulatory T Cells in Jejunum, Colon, and Cervical and Mesenteric Lymph Nodes of Dogs Naturally Infected with Leishmania infantum

2014 ◽  
Vol 82 (9) ◽  
pp. 3704-3712 ◽  
Author(s):  
Maria M. Figueiredo ◽  
Beatriz Deoti ◽  
Izabela F. Amorim ◽  
Aldair J. W. Pinto ◽  
Andrea Moraes ◽  
...  
Keyword(s):  
T Cells ◽  
Regulatory T Cells ◽  
Lymph Nodes ◽  
Leishmania Infantum ◽  
Parasite Load ◽  
Mesenteric Lymph Nodes ◽  
Content Type ◽  
Mesenteric Lymph ◽  
Tnf Α ◽  
Ifn Γ

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.

scholarly journals Protective Role of Nitric Oxide inStaphylococcus aureus Infection in Mice

1998 ◽  
Vol 66 (3) ◽  
pp. 1017-1022 ◽  
Author(s):  
Sanae Sasaki ◽  
Tomisato Miura ◽  
Shinsuke Nishikawa ◽  
Kyogo Yamada ◽  
Mayuko Hirasue ◽  
...  
Keyword(s):  
Nitric Oxide ◽  
Spleen Cell ◽  
Cell Cultures ◽  
Protective Role ◽  
Inos Mrna ◽  
No Production ◽  
Necrosis Factor Alpha ◽  
Tnf Α ◽  
Ifn Γ

ABSTRACT This study was carried out to determine the role of nitric oxide (NO) in Staphylococcus aureus infection in mice. NO production in spleen cell cultures was induced by heat-killed S. aureus. Expression of mRNA of the inducible isoform of NO synthase (iNOS) was induced in the spleens and kidneys of S. aureus-infected mice. When mice were treated with monoclonal antibodies (MAbs) against tumor necrosis factor alpha (TNF-α) or gamma interferon (IFN-γ) before S. aureus infection, the induction of iNOS mRNA expression in the kidneys was inhibited. These MAbs also inhibited NO production in spleen cell cultures stimulated with heat-killed S. aureus. NO production in the spleen cell cultures and levels of urinary nitrate plus nitrite were suppressed by treatment with aminoguanidine (AG), a selective inhibitor of iNOS. The survival rates of AG-treated mice were significantly decreased by either lethal or sublethal S. aureusinfections. However, an effect of AG administration on bacterial growth was not observed in the spleens and kidneys of mice during either type of infection. Production of TNF-α and IFN-γ was not affected by AG treatment in vitro and in vivo. These results suggest that NO plays an important role in protection from lethality by the infection, but the protective role of NO in host resistance against S. aureusinfection was not proved. Moreover, our results show that TNF-α and IFN-γ regulate NO production while NO may not be involved in the regulation of the production of these cytokines during S. aureus infection.

scholarly journals TMPRSS2 As an Influential Human Gene for COVID-19

2021 ◽  
Vol 4 (1) ◽  
Author(s):  
Sepideh Abdollahi ◽  
Pantea Izadi
Keyword(s):  
Risk Factors ◽  
Clinical Symptoms ◽  
Epidemiological Studies ◽  
Therapeutic Approaches ◽  
Diverse Range ◽  
Angiotensin Converting Enzyme 2 ◽  
Clinical Presentations ◽  
Health System Efficiency ◽  
Almost All

: In December 2019, the new virus, COVID-19, emerged and led to a pandemic respiratory acute disease. Almost all countries have experienced different rates of morbidity and mortality. These differences can be attributed to factors such as a diagnostic test capacity for COVID-19 and the health system efficiency. Besides the differences between countries related to the COVID-19 management, different patients represent a diverse range of clinical symptoms, from outpatient to patients admitted to the intensive care unit (ICU) due to the severity of symptoms. To gain deeper insights into such disparities in the severity of COVID-19 clinical presentations, epidemiological studies have reported risk factors such as old age, male sex, underlying chronic diseases such as diabetes, inflammatory and cardiovascular diseases, which have a bearing on susceptibility to COVID-19. In addition to these risk factors, the molecular mechanism involved in the virus entry process has been under investigation. Apart from a well-known protein called ACE2 (angiotensin-converting enzyme 2), which plays the receptor role for COVID-19, another essential protein in this pathway is TMPRSS2 (transmembrane protease, serine 2). This protease has a crucial role in effective membrane integration between the virus and the target cell. This process can affect the severity of the infection and the mortality rate of the disease. Thus, it seems that understanding the role of TMPRSS2 in COVID-19 infection can help better management by designing TMPRSS2 inhibitors drugs. Given the variants of the TMPRSS2 gene, which are associated with the severity of symptoms, people exposed to severe forms of this disease can be identified before the deterioration of the disease to adopt appropriate therapeutic approaches. Therefore, this study focused on the different levels of the TMPRSS2 interactions with COVID-19 virus and disease severity.

scholarly journals The Significance of Toll-Like Receptors in the Neuroimmunologic Background of Alcohol Dependence

2022 ◽  
Vol 12 ◽  
Author(s):  
Agnieszka Czerwińska-Błaszczyk ◽  
Edyta Pawlak ◽  
Tomasz Pawłowski
Keyword(s):  
Inflammatory Reaction ◽  
Clinical Symptoms ◽  
Behavioral Control ◽  
Immunological Response ◽  
Alcohol Addiction ◽  
Specific Response ◽  
Toll Like Receptors ◽  
Specific Immunity ◽  
The Family

Toll-like receptors (TLR) are a group of protein belonging to the family of Pattern Recognition Receptors (PRR) which have the ability to distinguish between an organism's own antigens and foreign ones and to induce immunological response. TLR play a significant part in non-specific immunity but at the same time they are also a vital element linking non-specific response to the specific one. A growing number of data seems to indicate that the non-specific immunity mechanisms affect the development and sustenance of alcohol addiction. Alcohol damages the organism's cells not only directly but also through an increase inintestinal permeability which induces innate immune response of peripheral blood cells. The signaling pathway of Toll-like receptors located on the surface of brain immune cells intensifies the inflammatory reaction and, through modifying gene expression of proinflammatory factors, unnaturally supports it. This overly protracted “sterile inflammatory reaction” positively correlates with alcohol craving affecting also the functioning of the reward system structures and increasing the risk of relapse of alcoholism. Recurrent alcoholic binges sensitize the microglia and cause an escalation in inflammatory reaction which also leads to neurodegeneration. The induction of innate immunity signaling pathways exposes clinical symptoms of alcohol addiction such as increased impulsivity, loss of behavioral control, depressive-anxiety symptoms and cognitive dysfunctions. Traditional methods of treating alcohol addiction have tended to focus predominantly on reducing symptoms which—given the frequency of relapses—seems insufficient. The aim of the present paper is to discuss the role of toll-like receptors as elements of the immunity system which, together with the nervous system, plays a crucial part in the pathogenesis of alcohol addiction. We also wish to present pharmacotherapeutic perspectives targeted at the neuroimmunological mechanisms of alcohol addiction.

scholarly journals Genome-Wide Association Study of Cell-Mediated Response in Dogs Naturally Infected by Leishmania infantum

2016 ◽  
Vol 84 (12) ◽  
pp. 3629-3637 ◽  
Author(s):  
Luís F. S. Batista ◽  
Yuri T. Utsunomiya ◽  
Thaís B. F. Silva ◽  
Raíssa A. Dias ◽  
Thaise Y. Tomokane ◽  
...  
Keyword(s):  
Lymph Nodes ◽  
Association Study ◽  
Leishmania Infantum ◽  
Genome Wide Association Study ◽  
Parasite Load ◽  
Genome Wide Association ◽  
Content Type ◽  
Genome Wide ◽  
Tnf Α ◽  
Ifn Γ

A genome-wide association study (GWAS) could unravel the complexity of the cell-mediated immunity (CMI) to canine leishmaniasis (CanL). Therefore, we scanned 110,165 single-nucleotide polymorphisms (SNPs), aiming to identify chromosomal regions associated with the leishmanin skin test (LST), lymphocyte proliferation assay (LPA), and cytokine responses to further understand the role played by CMI in the outcome of naturalLeishmania infantuminfection in 189 dogs. Based on LST and LPA, four CMI profiles were identified (LST−/LPA−, LST+/LPA−, LST−/LPA+, and LST+/LPA+), which were not associated with subclinically infected or diseased dogs. LST+/LPA+dogs showed increased interferon gamma (IFN-γ) and tumor necrosis factor alpha (TNF-α) levels and mild parasitism in the lymph nodes, whereas LST−/LPA+dogs, in spite of increased IFN-γ, also showed increased interleukin-10 (IL-10) and transforming growth factor β (TGF-β) levels and the highest parasite load in lymph nodes. Low T cell proliferation under low parasite load suggested thatL. infantumwas not able to induce effective CMI in the early stage of infection. Altogether, genetic markers explained 87%, 16%, 15%, 11%, 0%, and 0% of phenotypic variance in TNF-α, TGF-β, LST, IL-10, IFN-γ, and LPA, respectively. GWAS showed that regions associated with TNF-α include the following genes:IL12RB1,JAK3,CCRL2,CCR2,CCR3, andCXCR6, involved in cytokine and chemokine signaling; regions associated with LST, includingCOMMD5andSHARPIN, involved in regulation of NF-κB signaling; and regions associated with IL-10, includingLTBP1andRASGRP3, involved in T regulatory lymphocytes differentiation. These findings pinpoint chromosomic regions related to the cell-mediated response that potentially affect the clinical complexity and the parasite replication in canineL. infantuminfection.

scholarly journals Hemostatic assessment of dogs associated with hepatic parasite load of Leishmania infantum chagasi

2016 ◽  
Vol 25 (2) ◽  
pp. 244-247
Author(s):  
Mariana de Medeiros Torres ◽  
Arleana do Bom Parto Ferreira de Almeida ◽  
Daphine Ariadne Jesus de Paula ◽  
Adriane Jorge Mendonça ◽  
Luciano Nakazato ◽  
...  
Keyword(s):  
Visceral Leishmaniasis ◽  
Leishmania Infantum ◽  
Rank Correlation ◽  
Immunological Response ◽  
Parasite Load ◽  
Serum Biochemistry ◽  
Screening Tests ◽  
Hemorrhagic Diathesis ◽  
Spearman’S Rank Correlation ◽  
Leishmania Infantum Chagasi

Abstract Leishmania infantum chagasi liver parasite load was compared to hemostatic abnormalities, as well as to clinical, laboratorial, and histopathological findings in dogs with visceral leishmaniasis. The liver parasite load of 30 dogs L. infantum chagasi naturally-infected was evaluated by quantitative real- time PCR and the results were compared with serum biochemistry and primary and secondary hemostasis findings. Moreover, hepatic histological lesions were described in these dogs. Prolonged bleeding time, prothrombin time (PT), and activated partial thromboplastin time (APTT), were observed in the group with visceral leishmaniasis. Eleven dogs presented inflammatory liver lesions, with predominance of mild multifocal mononuclear periportal hepatitis. No association between the presence of parasites and abnormalities in screening tests was observed by Spearman’s rank correlation coefficient. The clinical progression in leishmaniasis is associated with the occurrence of hemorrhagic diathesis, which depends not only on the presence of the parasite but also the inflammatory process, compromised immunological response, hepatic and renal failure in symptomatic dogs.

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