scholarly journals Morphological Findings in Trophozoites during Amoebic Abscess Development in Misoprostol-Treated BALB/c Mice

2015 ◽  
Vol 2015 ◽  
pp. 1-7 ◽  
Author(s):  
Andrés Aceves-Cano ◽  
Rocío Gaytán-Ochoa ◽  
Ernesto Ramos-Martínez ◽  
Gilberto Erosa de la Vega ◽  
Carmen González-Horta ◽  
...  
Keyword(s):  
Immune Response ◽  
Image Analysis ◽  
Inflammatory Process ◽  
Resistance Mechanisms ◽  
Natural Resistance ◽  
Amoebic Liver Abscess ◽  
Prostaglandin E ◽  
Male Mice ◽  
Morphological Findings ◽  
Amoebic Abscess

During amoebic liver abscess (ALA) formation in susceptible animals, immune response is regulated by prostaglandin E2(PGE2) dependent mechanisms. The aim of this study was to analyze the effect of misoprostol (MPL), a PGE1analogue, on ALA formation in BALB/c mice. Male mice from BALB/c strain were intrahepatically infected with7.5×105trophozoites ofE. histolyticastrain HM1:IMSS and treated with 10−4 M of MPL daily until sacrifice at 2, 4, and 7 days postinfection (p.i.). ALA formation was evaluated at 2, 4, and 7 days postinfection; trophozoite morphology was analyzed using immunohistochemistry and image analysis. Results showed an increase in frequency of ALA formation in infected and MPL-treated mice only at 2 days p.i. (P=0.03). A significant diminution in the size of trophozoites was detected in abscesses from mice independently of MPL treatment (from5.8±1.1 µm at 2 days p.i. to2.7±1.9 µm at 7 days p.i.) compared with trophozoites dimensions observed in susceptible hamsters (9.6±2.7 µm) (P<0.01). These results suggest that MPL treatment may modify the adequate control of inflammatory process to allow the persistence of trophozoites in the liver; however, natural resistance mechanisms cannot be discarded.

scholarly journals Mechanisms of natural resistance of Balb/c mice to experimental liver amoebiasis

2019 ◽  
Vol 39 (5) ◽  
Author(s):  
Azucena Cortes ◽  
Mario Nequiz ◽  
Janeth Sandoval ◽  
Edith Mendoza ◽  
Marco Gudiño ◽  
...  
Keyword(s):  
Mouse Liver ◽  
Resistance Mechanisms ◽  
Chemotactic Activity ◽  
Natural Resistance ◽  
Amoebic Liver Abscess ◽  
Temporal Course ◽  
Experimental Liver

AbstractEntamoeba histolytica is the parasite responsible for human amoebiasis. The analysis of the natural resistance mechanisms of some rodents to amoebic liver abscess (ALA) may reveal alternative pathogenicity mechanisms to those previously discovered in the experimental model of ALA in hamsters. In this work the natural resistance of BALB/c mice to ALA was explored by performing: (i) in vivo chemotaxis analysis with a specifically designed chamber; (ii) in vitro amoebic survival in fresh and decomplemented serum; (iii) histological temporal course analysis of ALA development in mice with different treatments (hypocomplementemic, hyperimmune and treated with iNOS and NADPH oxidase inhibitors) and (iv) mouse liver amoebic infection by both in situ implantation of ALA from hamsters and inoculation of parasites into the peritoneal cavity. The results show that E. histolytica clearance from the mouse liver is related to a low chemotactic activity of complement, which results in poor inflammatory response and parasite inability to cause tissue damage. Also, the absence of amoebic tropism for the mouse liver is correlated with resistance to experimental liver amoebiasis.

scholarly journals Complement is a rat natural resistance factor to amoebic liver infection

2018 ◽  
Vol 38 (5) ◽  
Author(s):  
Alfonso Olivos-García ◽  
Mario Nequiz ◽  
Scarlet Liceaga ◽  
Edith Mendoza ◽  
Porfirio Zúñiga ◽  
...  
Keyword(s):  
Alternative Pathway ◽  
Resistance Mechanisms ◽  
Factor H ◽  
Natural Resistance ◽  
Amoebic Liver Abscess ◽  
Rat Serum ◽  
Poor Countries ◽  
Membrane Complex ◽  
Novel Therapeutic Strategies

Amoebiasis is a parasitic disease caused by Entamoeba histolytica. This illness is prevalent in poor countries causing 100,000 deaths worldwide. Knowledge of the natural resistance mechanisms of rats to amoebic liver abscess (ALA) development may help to discover new pathogenic factors and to design novel therapeutic strategies against amoebiasis. In this work, histologic analyses suggested that the complement system may play a central role in rat natural resistance to ALA. E. histolytica trophozoites disappeared from rat liver within 6 h post-infection with minimal or no inflammatory infiltrate. In vitro findings indicate that rat complement was lethal for the parasite. Furthermore, hamsters became resistant to ALA by intravenous administration of fresh rat serum before infection. The amoebicidal potency of rat complement was 10 times higher than hamster complement and was not related to their respective CH50 levels. The alternative pathway of complement plays a central role in its toxicity to E. histolytica since trypan blue, which is a C3b receptor inhibitor, blocks its amoebicidal activity. These results suggest that amoebic membrane affinity, high for C3b and/or low for Factor H, in comparison with the hamster ones, may result in higher deposition of membrane complex attack on parasite surface and death.

scholarly journals Combining mTOR Inhibitors and T Cell-Based Immunotherapies in Cancer Treatment

Cancers ◽  
2021 ◽  
Vol 13 (6) ◽  
pp. 1359
Author(s):  
Alexandre el Hage ◽  
Olivier Dormond
Keyword(s):  
Immune Response ◽  
T Cell ◽  
Antitumor Immunity ◽  
Tumor Development ◽  
Mtor Inhibitors ◽  
Resistance Mechanisms ◽  
Cancer Cell Growth ◽  
Anticancer Effects ◽  
Therapeutic Opportunity ◽  
Control Tumor

mTOR regulates several processes that control tumor development, including cancer cell growth, angiogenesis and the immune response to tumor. Accordingly, mTOR inhibitors have been thoroughly explored in cancer therapy but have failed to provide long-lasting anticancer benefits. Several resistance mechanisms that counteract the antitumor effect of mTOR inhibitors have been identified and have highlighted the need to use mTOR inhibitors in combination therapies. In this context, emerging evidence has demonstrated that mTOR inhibitors, despite their immunosuppressive properties, provide anticancer benefits to immunotherapies. In fact, mTOR inhibitors also display immunostimulatory effects, in particular by promoting memory CD8+ T cell generation. Hence, mTOR inhibitors represent a therapeutic opportunity to promote antitumor CD8 responses and to boost the efficacy of different modalities of cancer immunotherapy. In this context, strategies to reduce the immunosuppressive activity of mTOR inhibitors and therefore to shift the immune response toward antitumor immunity will be useful. In this review, we present the different classes of mTOR inhibitors and discuss their effect on immune cells by focusing mainly on CD8+ T cells. We further provide an overview of the different preclinical studies that investigated the anticancer effects of mTOR inhibitors combined to immunotherapies.

Development of A First-Responder Fluorescence Reader for Microarray Cytokine Assay of Human Immune Response to Disease

2007 ◽  
Vol 1004 ◽  
Author(s):  
David B. Fenner ◽  
David I Rosen ◽  
Anthony A Ferrante ◽  
Amy E Stevens ◽  
Chad E Bigelow ◽  
...  
Keyword(s):  
Immune Response ◽  
Image Analysis ◽  
Optical Design ◽  
Human Saliva ◽  
Minimally Processed ◽  
Portable Apparatus ◽  
New Apparatus ◽  
Human Immune Response ◽  
Human Immune ◽  
Cytokine Assay

AbstractDevelopment of field portable apparatus and methods for cytokine assay of human saliva by fluorescent-reporting microarray plates is described. Multiplexed assay of 12 cytokines for minimally-processed saliva is read with a CCD-based imager under LED excitation. Immune responsive cytokines are measured at levels significant for indication of human disease state. The motivational context for the new apparatus development, the general optical design issues, saliva protocol, and image analysis are described.

scholarly journals Clinicopathological study on presentation, diagnosis and management of liver abscess in Bhopal region

2017 ◽  
Vol 4 (8) ◽  
pp. 2572
Author(s):  
Anshul Siroliya ◽  
Mahendra Damor ◽  
M. C. Songra
Keyword(s):  
Observational Study ◽  
Liver Abscess ◽  
Prospective Observational Study ◽  
Pyogenic Liver Abscess ◽  
Amoebic Liver Abscess ◽  
Age Group ◽  
Catheter Drainage ◽  
Liver Abscesses ◽  
Male Preponderance ◽  
Amoebic Abscess

Background: This prospective observational study is carried out to study cases of liver abscess and to determine demographic profile, spectrum of clinical presentations, aetiology, laboratory investigations. The objective of the study was to evaluate efficacy of Ultrasonographic (radiological) studies in determining the aetiology and in differentiating from other liver pathologies which may change the treatment outcome, bacteriological and serological characteristics, to study the influence of alcohol, diabetics and immunocompromised diseases (esp. HIV) leading to increased incidence of liver abscess and to evaluate efficacy, recurrence rate, complications, morbidity and mortality, duration of hospital stay associated with different management Strategies.Methods: This prospective observational study was carried out in Department of Surgery, Gandhi Medical College Bhopal and Associated Hamidia Hospital, Bhopal between July 2015 to October 2016.Results: Amoebic abscess (74%) is more common than pyogenic abscess (26%). Amoebic abscess is common in the age group of 31-50 years (73%), pyogenic in the age group of 51-70 years (73.1%). Male preponderance is found in case of amoebic liver abscess (90.5%). Right lobe involvement in common. Right upper quadrant pain, tenderness and fever are the most common clinical features. Alcoholism is most common risk factor (71.6%) and diabetes mellitus has strong association with pyogenic liver abscess (15.4%). E coli (19.2%) and klebsiella (11.5%) are the most common organisms cultured. Medical therapy is more useful in case of amoebic liver abscess (58.1%) while catheter drainage is more useful in case of pyogenic liver abscess (61.5%). Pleuropulmonary complications are much more common and complications rate is more common among pyogenic group.Conclusions: In our study, alcohol was found to be the most common predisposing factor for liver abscesses (68%), this underpin the finding of other studies. Amoebic liver abscess is a medically treated common infection prevailing in unhygienic condition, affecting people mostly between 30-40 years of age whereas pyogenic liver abscess patient commonly falls between 50-70 years age group. Both liver abscesses show a male preponderance. The present study also corroborates the catheter drainage procedure as a superior modality in treating pyogenic liver abscess.

Natural Resistance Mechanisms to Viruses in Barley

2007 ◽  
pp. 465-501 ◽  
Author(s):  
Michael C. Edwards ◽  
Jennifer Bragg ◽  
Andrew O. Jackson
Keyword(s):  
Resistance Mechanisms ◽  
Natural Resistance

A new view of prostaglandin E regulation of the immune response

1991 ◽  
Vol 12 (10) ◽  
pp. 349-352 ◽  
Author(s):  
Richard P. Phipps ◽  
Sidney H. Stein ◽  
Rachel L. Roper
Keyword(s):  
Immune Response ◽  
Prostaglandin E ◽  
New View

scholarly journals Innate Immune Receptors and Defense Against Primary Pathogenic Fungi

Vaccines ◽  
2020 ◽  
Vol 8 (2) ◽  
pp. 303
Author(s):  
Theo N. Kirkland ◽  
Joshua Fierer
Keyword(s):  
Immune Response ◽  
Pathogenic Fungi ◽  
Vital Role ◽  
Innate Immune ◽  
Natural Resistance ◽  
Opportunistic Fungi ◽  
Immune Receptors ◽  
Invasive Infections ◽  
Paracoccidioides Spp ◽  
Human Infections

The innate immune system is critical for natural resistance to all pathogenic microorganisms, including fungi. The innate response plays a vital role in resistance to infections before the antigen-specific immune response and also influences antigen-specific adaptive immunity. There are many different receptors for the innate immune response to fungi, and some receptors have been found to play a significant role in the response to human infections with opportunistic fungi. Most human infections are caused by opportunistic fungi, but a small number of organisms are capable of causing infections in normal hosts. The primary pathogenic fungi that cause invasive infections include Blastomyces spp., Cryptococcus gattii, Coccidioides spp., Histoplasma spp., and Paracoccidioides spp. In this review of innate immune receptors that play a role in infections caused by these organisms, we find that innate immunity differs between organisms.

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