scholarly journals Within-host mechanisms of immune regulation explain the contrasting dynamics of two helminth species in both single and dual infections

2020 ◽  
Vol 16 (11) ◽  
pp. e1008438
Author(s):  
Chiara Vanalli ◽  
Lorenzo Mari ◽  
Lorenzo Righetto ◽  
Renato Casagrandi ◽  
Marino Gatto ◽  
...  
Keyword(s):  
Immune Responses ◽  
Immune Regulation ◽  
General Trend ◽  
Laboratory Data ◽  
Helminth Species ◽  
Multiple Infections ◽  
Host Immune Responses ◽  
Parasitic Helminths ◽  
Helminth Infections ◽  
Dual Infections

Variation in the intensity and duration of infections is often driven by variation in the network and strength of host immune responses. While many of the immune mechanisms and components are known for parasitic helminths, how these relationships change from single to multiple infections and impact helminth dynamics remains largely unclear. Here, we used laboratory data from a rabbit-helminth system and developed a within-host model of infection to investigate different scenarios of immune regulation in rabbits infected with one or two helminth species. Model selection suggests that the immunological pathways activated against Trichostrongylus retortaeformis and Graphidium strigosum are similar. However, differences in the strength of these immune signals lead to the contrasting dynamics of infections, where the first parasite is rapidly cleared and the latter persists with high intensities. In addition to the reactions identified in single infections, rabbits with both helminths also activate new pathways that asymmetrically affect the dynamics of the two species. These new signals alter the intensities but not the general trend of the infections. The type of interactions described can be expected in many other host-helminth systems. Our immune framework is flexible enough to capture different mechanisms and their complexity, and provides essential insights to the understanding of multi-helminth infections.

Excretory–secretory products of helminth parasites: effects on host immune responses

Parasitology ◽  
1988 ◽  
Vol 96 (S1) ◽  
pp. S123-S166 ◽  
Author(s):  
M. W. Lightowlers ◽  
M. D. Rickard
Keyword(s):  
Immune Responses ◽  
Inflammatory Responses ◽  
Helminth Parasites ◽  
Host Immune Responses ◽  
Parasitic Helminths ◽  
Protective Antigens ◽  
Helminth Infections ◽  
Secretory Products ◽  
Antigen Presenting ◽  
Host Parasite

SUMMARYParasitic helminths excrete or secrete (ES) a variety of molecules into their mammalian hosts. The effects of these ES products on the host's immune responses are reviewed. Investigations into the source of antigenic or immunoregulatory ES products have identified the cuticular and tegumental surfaces of some nematodes and trematodes respectively as being important sources of ES products; other ES molecules are released through specialized excretory or secretory organs. It is proposed that the active shedding of surface antigens may serve as an important source of parasite antigens available to the immune system in a form in which they can be taken up and processed by antigen-presenting dendritic cells, macro-phages and certain B cells for presentation to T helper cells. The ES products of nematodes, trematodes and cestodes contribute to immune evasion strategies of the parasites through mechanisms including shedding of surface-bound ligands and cells, alteration of lymphocyte, macrophage and granulocyte functions and modulation of complement and other host inflammatory responses. Immunopathology may be induced by ES products as in the development of granulomas around entrapped schistosome eggs. In some host – parasite systems ES antigens may induce host-protective immune responses and this source of protective antigens has been utilized in the successful vaccination against helminth infections, particularly against infection with trichurid nematodes and the metacestode stage of cestode parasites. The use of ES antigens in immunodiagnosis of helminth infection is also briefly discussed.

scholarly journals Prevalence, Intensity and Risks Involved in Helminth Infections in Domestic Mountain Pony and Balkan Donkey in Nature Park Stara Planina, Serbia

2021 ◽  
Author(s):  
Slavica Živković ◽  
Ivan Pavlović ◽  
Bojana Mijatović ◽  
Ivana Trailović ◽  
Dragiša Trailović
Keyword(s):  
Risk Factors ◽  
Helminth Species ◽  
Parasitic Helminths ◽  
Gastrointestinal Helminth ◽  
Helminth Infections ◽  
Helminthic Infections ◽  
Faecal Egg Count ◽  
Nature Park ◽  
The Mean ◽  
And Gender

Background: This study aimed to investigate the prevalence, intensity and risk factors (age and gender) promoting the intestinal helminthic infections of the Domestic mountain ponies and Balkan donkeys in Serbia. Methods: Prevalence, intensity and risk factors influencing helminth infection in horses (n=39) and donkeys (n=18) at the site of Nature Park Stara Planina, were studied from May to Sep 2015. The presence of one or several gastrointestinal helminth species was confirmed by faecal flotation in 97.43% of horses and 88.88% of donkeys included in the monitoring. The identified helminth species were Trichostrongylus axei, Strongylus edentatus, S. vulgaris, Parascaris equorum, Dictyocaulus arnfieldi and Anoplocephala magna in 84.61%, 46.15%, 5.13%, 58.97%, 94.87% and 38.46% of horses, respectively. The significant association of infection with P. equorum and sex of horses was established. (χ2=13.33, P<0.01). Results: The prevalence of parasitic helminths identified in donkeys was the following: D. arnfieldi, T. axei, Pa. equorum, S. vulgaris, A. margna and Strongyloides westeri in 55.55%, 38.89%, 27.78%, 22.22% and 22.22% of donkeys, respectively. Moreover, the mean faecal egg count was higher in donkeys (369.9 EPG - egg per gram) than in horses (250.2 EPG). The association between the age and the mean EPG was significant (P<0.05) in both equine species. Conclusion: The results of the investigation provided basic information that can be helpful for planning strategic control of nematode infection in equine population in Nature Reserves in Serbia.

scholarly journals Comprehensive Transcriptome Meta-analysis to Characterize Host Immune Responses in Helminth Infections

2016 ◽  
Vol 10 (4) ◽  
pp. e0004624 ◽  
Author(s):  
Guangyan Zhou ◽  
Mary M. Stevenson ◽  
Timothy G. Geary ◽  
Jianguo Xia
Keyword(s):  
Immune Responses ◽  
Meta Analysis ◽  
Host Immune Responses ◽  
Helminth Infections

scholarly journals Modulation of Specific and Allergy-Related Immune Responses by Helminths

2011 ◽  
Vol 2011 ◽  
pp. 1-18 ◽  
Author(s):  
Emilia Daniłowicz-Luebert ◽  
Noëlle L. O'Regan ◽  
Svenja Steinfelder ◽  
Susanne Hartmann
Keyword(s):  
Immune Responses ◽  
Immune Regulation ◽  
Host Response ◽  
Allergic Inflammation ◽  
Master Regulators ◽  
Host Immune Responses ◽  
Complex Mechanisms ◽  
Underlying Mechanisms ◽  
The Impact

Helminths are master regulators of host immune responses utilising complex mechanisms to dampen host protective Th2-type responses and favour long-term persistence. Such evasion mechanisms ensure mutual survival of both the parasite and the host. In this paper, we present recent findings on the cells that are targeted by helminths and the molecules and mechanisms that are induced during infection. We discuss the impact of these factors on the host response as well as their effect in preventing the development of aberrant allergic inflammation. We also examine recent findings on helminth-derived molecules that can be used as tools to pinpoint the underlying mechanisms of immune regulation or to determine new anti-inflammatory therapeutics.

Role of convalescent plasma therapy in new Coronavirus disease (nCOVID-19): A review

2020 ◽  
Vol 11 (SPL1) ◽  
pp. 546-549
Author(s):  
Shweta Dadarao Parwe ◽  
Milind Abhimanyu Nisargandha ◽  
Rishikesh Thakre
Keyword(s):  
Clinical Trial ◽  
Immune Responses ◽  
Indian Population ◽  
Preventive Treatment ◽  
The Body ◽  
Therapeutic Antibodies ◽  
Plasma Therapy ◽  
Host Immune Responses ◽  
Transparent Liquid

Hitherto, there is no proper line of treatment for the new (nCOVID19). The development of unique antiviral drugs has taken precedence. Therapeutic antibodies () will be a significantly beneficial agent against nCOVID-19. Here the host immune responses to new discussed in this review provide strategy and further treatment and understanding of clinical interventions against nCOVID-19. Plasma therapy uses the antibodies found in the blood of people recovering (or convalesced) from an infection to treat infected patients. When an infection occurs, the body begins producing proteins specially made to kill the germ, called antibodies. Those antibodies coat specifically plasma in the blood of survivors, the yellow transparent liquid blood portion for months or even years. research assesses plasma use from Convalescent patients of infected with nCOVID-19 as a possible preventive treatment. But it is not yet recommended as a line of treatment, and it is used as a clinical trial in the new in Indian population.

scholarly journals Extracellular Vesicles of Mesenchymal Stem Cells: Therapeutic Properties Discovered with Extraordinary SuccessOK

Biomedicines ◽  
2021 ◽  
Vol 9 (6) ◽  
pp. 667
Author(s):  
Gabriella Racchetti ◽  
Jacopo Meldolesi
Keyword(s):  
Stem Cells ◽  
Mesenchymal Stem Cells ◽  
Immune Responses ◽  
Extracellular Vesicles ◽  
Immune Regulation ◽  
Great Increase ◽  
The Body ◽  
Cell Aging ◽  
Therapeutic Effects ◽  
Therapeutic Properties

Mesenchymal stem cells (MSCs), the cells distributed in the stromas of the body, are known for various properties including replication, the potential of various differentiations, the immune-related processes including inflammation. About two decades ago, these cells were shown to play relevant roles in the therapy of numerous diseases, dependent on their immune regulation and their release of cytokines and growth factors, with ensuing activation of favorable enzymes and processes. Such discovery induced great increase of their investigation. Soon thereafter, however, it became clear that therapeutic actions of MSCs are risky, accompanied by serious drawbacks and defects. MSC therapy has been therefore reduced to a few diseases, replaced for the others by their extracellular vesicles, the MSC-EVs. The latter vesicles recapitulate most therapeutic actions of MSCs, with equal or even better efficacies and without the serious drawbacks of the parent cells. In addition, MSC-EVs are characterized by many advantages, among which are their heterogeneities dependent on the stromas of origin, the alleviation of cell aging, the regulation of immune responses and inflammation. Here we illustrate the MSC-EV therapeutic effects, largely mediated by specific miRNAs, covering various diseases and pathological processes occurring in the bones, heart and vessels, kidney, and brain. MSC-EVs operate also on the development of cancers and on COVID-19, where they alleviate the organ lesions induced by the virus. Therapy by MSC-EVs can be improved by combination of their innate potential to engineering processes inducing precise targeting and transfer of drugs. The unique properties of MSC-EVs explain their intense studies, carried out with extraordinary success. Although not yet developed to clinical practice, the perspectives for proximal future are encouraging.

scholarly journals Effect of intensive treatment for schistosomiasis on immune responses to vaccines among rural Ugandan island adolescents: randomised controlled trial protocol A for the ‘POPulation differences in VACcine responses’ (POPVAC) programme

BMJ Open ◽  
2021 ◽  
Vol 11 (2) ◽  
pp. e040426
Author(s):  
Gyaviira Nkurunungi ◽  
Ludoviko Zirimenya ◽  
Jacent Nassuuna ◽  
Agnes Natukunda ◽  
Prossy N Kabuubi ◽  
...  
Keyword(s):  
Immune Responses ◽  
Low Income ◽  
Controlled Trial ◽  
Interferon Γ ◽  
Population Differences ◽  
Vaccine Response ◽  
Vaccine Responses ◽  
Helminth Infections ◽  
Registration Number ◽  
Randomised Controlled

IntroductionSeveral licensed and investigational vaccines have lower efficacy, and induce impaired immune responses, in low-income versus high-income countries and in rural, versus urban, settings. Understanding these population differences is essential to optimising vaccine effectiveness in the tropics. We suggest that repeated exposure to and immunomodulation by chronic helminth infections partly explains population differences in vaccine response.Methods and analysisWe have designed an individually randomised, parallel group trial of intensive versus standard praziquantel (PZQ) intervention against schistosomiasis, to determine effects on vaccine response outcomes among school-going adolescents (9–17 years) from rural Schistosoma mansoni-endemic Ugandan islands. Vaccines to be studied comprise BCG on day ‘zero’; yellow fever, oral typhoid and human papilloma virus (HPV) vaccines at week 4; and HPV and tetanus/diphtheria booster vaccine at week 28. The intensive arm will receive PZQ doses three times, each 2 weeks apart, before BCG immunisation, followed by a dose at week 8 and quarterly thereafter. The standard arm will receive PZQ at week 8 and 52. We expect to enrol 480 participants, with 80% infected with S. mansoni at the outset.Primary outcomes are BCG-specific interferon-γ ELISpot responses 8 weeks after BCG immunisation and for other vaccines, antibody responses to key vaccine antigens at 4 weeks after immunisation. Secondary analyses will determine the effects of intensive anthelminthic treatment on correlates of protective immunity, on waning of vaccine response, on priming versus boosting immunisations and on S. mansoni infection status and intensity. Exploratory immunology assays using archived samples will enable assessment of mechanistic links between helminths and vaccine responses.Ethics and disseminationEthics approval has been obtained from relevant ethics committes of Uganda and UK. Results will be shared with Uganda Ministry of Health, relevant district councils, community leaders and study participants. Further dissemination will be done through conference proceedings and publications.Trial registration numberISRCTN60517191.

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