Full Text Available

Note: Clicking the button above will open the full text document at the original institutional repository in a new window.

The role of Cysteinyl leukotriene receptor-1 during experimental helminth infections in murine model

Cysteinyl leukotrienes (cysLTs) are potent inflammatory lipid mediators that play a major role in the pathophysiology of inflammatory diseases. They signal primarily through cysteinyl leukotriene receptor-1 (cysLTR1) and have been reported to drive Th2 immune responses. Initiation and amplification...

Full description

Saved in:
Bibliographic Details
Main Author: Mosala, Paballo Pertunia
Other Authors: Brombacher, Frank
Format: Thesis
Language:English
Published: Department of Clinical Laboratory Sciences 2021
Subjects:
Tags: Add Tag
No Tags, Be the first to tag this record!
_version_ 1867613219372138496
access_status_str Open Access
author Mosala, Paballo Pertunia
author2 Brombacher, Frank
author_browse Brombacher, Frank
Mosala, Paballo Pertunia
author_facet Brombacher, Frank
Mosala, Paballo Pertunia
author_sort Mosala, Paballo Pertunia
collection Thesis
description Cysteinyl leukotrienes (cysLTs) are potent inflammatory lipid mediators that play a major role in the pathophysiology of inflammatory diseases. They signal primarily through cysteinyl leukotriene receptor-1 (cysLTR1) and have been reported to drive Th2 immune responses. Initiation and amplification of robust Th2 immune responses is crucial for conferring protective immunity to helminth (Schistosoma mansoni and Nippostrongylus brasiliensis) infection in mice. The role played by cysLTs in the development of protective immune responses to helminth infections is not well documented. Hence in the present study, we investigated the role of cysLTs during helminth infection using cysteinyl leukotriene receptor-1 deficient (cysLTR1-/- ) mice. Under steady state conditions, young naïve cysLTR1-/- mice did not reveal any significant alteration of the cellular, tissue and phenotypic profile although we did observe expansion of central memory T cells (Tcm) in secondary lymphoid organs in cysLTR1-/- as compared to wildtype mice. Primary infection with N. brasiliensis indicated increased worm burden in cysLTR1-/- mice at day 7 post infection and a delay in the resolution of infection by day 9 post infection when compared to wild type mice. Furthermore, we observed reduced Th2 immune responses as well as impaired contractility of the small intestine, which are key features required for protective immunity to N. brasiliensis infection. Furthermore, recall of memory responses to N. brasiliensis was abrogated in cysLTR1 -/- mice, with higher numbers of adult worms recovered at day 5 post re-infection in cysLTR1-/- mice comparison with wild type mice. Additionally, cysLTR1-/- mice exhibited impaired production of IL-13 in the lungs and draining lymph nodes compared with wildtype mice. Finally, there was reduced recruitment of effector CD4+ T cells and central memory CD4+ T cells in the lungs of cysLTR1 deficient mice compared to control mice. Taken together, these data demonstrated an essential role played by cysLTR1 in clearance and resolution of N. brasiliensis infection. CysLTR1-/- mice survived acute S. mansoni infection similarly to wildtype mice. In addition, cysLTR1-/- mice displayed reduced granulomatous inflammation and reduced cellular responses in the liver compared with wildtype mice. Further analysis revealed reduced gut fibrosis but cytokine production, immune cell recruitment in the gut and both type 1 and type 2 antibodies were found to be comparable between wildtype and knockout mice, demonstrating that cysLTs signaling through cysLTR1 contribute to granuloma formation in the liver. Similar to acute schistosomiasis, cysLTR1-/- mice were not susceptible to chronic schistosomiasis and indicated by prolonged host survival. This increased host survival observed in cysLTR1-/- mice was associated with reduced granulomatous inflammation, reduced fibrosis and hepatocellular damage, impaired production of IL-4 in the liver, and reduced intracellular secretion of IL4 by CD4+ T cells and ILC2s in cysLTR1-/- mice compared with wildtype mice. Furthermore, we observed reduced granulomatous inflammation in the lungs of chronically infected cysLTR1-/- mice despite the heightened Th2 immune response in the lungs. Collectively, these data revealed that disruption of cysLTR1 leads to reduced granulomatous inflammation and reduced production of IL-4 in the liver during chronic schistosomiasis. In conclusion, the current study demonstrated both positive and negative roles for cysLTs signaling through cysLTR1 during different helminth infection models. Absence of cysLTR1 during N. brasiliensis leads to delayed expulsion of adult worms and impaired recall of memory responses, indicating that cysteinyl leukotriene signaling via cysLTR1 is essential for orchestrating host protective responses. On the other hand, signaling via cysLTR1 appears to be dispensable for the development of host protective responses during acute schistosomiasis in mice. However, mice deficient of cysLTR1 had reduced liver pathology during chronic schistosomiasis, suggesting that inhibition of this receptor could be a potential therapy for reducing granulomatous liver pathology.
format Thesis
id oai:open.uct.ac.za:11427/33872
institution University of Cape Town (South Africa)
language eng
last_indexed 2026-06-10T12:32:39.476Z
license_str Not specified — see source repository
provenance_str_mv Harvested via OAI-PMH from UCTD — University of Cape Town Open Access Repository
publishDate 2021
publishDateRange 2021
publishDateSort 2021
publisher Department of Clinical Laboratory Sciences
publisherStr Department of Clinical Laboratory Sciences
record_format dspace
source_str UCTD — University of Cape Town Open Access Repository
spelling oai:open.uct.ac.za:11427/33872 The role of Cysteinyl leukotriene receptor-1 during experimental helminth infections in murine model Mosala, Paballo Pertunia Brombacher, Frank Ndlovu, Hlumani Clinical Science and Immunology Cysteinyl leukotrienes (cysLTs) are potent inflammatory lipid mediators that play a major role in the pathophysiology of inflammatory diseases. They signal primarily through cysteinyl leukotriene receptor-1 (cysLTR1) and have been reported to drive Th2 immune responses. Initiation and amplification of robust Th2 immune responses is crucial for conferring protective immunity to helminth (Schistosoma mansoni and Nippostrongylus brasiliensis) infection in mice. The role played by cysLTs in the development of protective immune responses to helminth infections is not well documented. Hence in the present study, we investigated the role of cysLTs during helminth infection using cysteinyl leukotriene receptor-1 deficient (cysLTR1-/- ) mice. Under steady state conditions, young naïve cysLTR1-/- mice did not reveal any significant alteration of the cellular, tissue and phenotypic profile although we did observe expansion of central memory T cells (Tcm) in secondary lymphoid organs in cysLTR1-/- as compared to wildtype mice. Primary infection with N. brasiliensis indicated increased worm burden in cysLTR1-/- mice at day 7 post infection and a delay in the resolution of infection by day 9 post infection when compared to wild type mice. Furthermore, we observed reduced Th2 immune responses as well as impaired contractility of the small intestine, which are key features required for protective immunity to N. brasiliensis infection. Furthermore, recall of memory responses to N. brasiliensis was abrogated in cysLTR1 -/- mice, with higher numbers of adult worms recovered at day 5 post re-infection in cysLTR1-/- mice comparison with wild type mice. Additionally, cysLTR1-/- mice exhibited impaired production of IL-13 in the lungs and draining lymph nodes compared with wildtype mice. Finally, there was reduced recruitment of effector CD4+ T cells and central memory CD4+ T cells in the lungs of cysLTR1 deficient mice compared to control mice. Taken together, these data demonstrated an essential role played by cysLTR1 in clearance and resolution of N. brasiliensis infection. CysLTR1-/- mice survived acute S. mansoni infection similarly to wildtype mice. In addition, cysLTR1-/- mice displayed reduced granulomatous inflammation and reduced cellular responses in the liver compared with wildtype mice. Further analysis revealed reduced gut fibrosis but cytokine production, immune cell recruitment in the gut and both type 1 and type 2 antibodies were found to be comparable between wildtype and knockout mice, demonstrating that cysLTs signaling through cysLTR1 contribute to granuloma formation in the liver. Similar to acute schistosomiasis, cysLTR1-/- mice were not susceptible to chronic schistosomiasis and indicated by prolonged host survival. This increased host survival observed in cysLTR1-/- mice was associated with reduced granulomatous inflammation, reduced fibrosis and hepatocellular damage, impaired production of IL-4 in the liver, and reduced intracellular secretion of IL4 by CD4+ T cells and ILC2s in cysLTR1-/- mice compared with wildtype mice. Furthermore, we observed reduced granulomatous inflammation in the lungs of chronically infected cysLTR1-/- mice despite the heightened Th2 immune response in the lungs. Collectively, these data revealed that disruption of cysLTR1 leads to reduced granulomatous inflammation and reduced production of IL-4 in the liver during chronic schistosomiasis. In conclusion, the current study demonstrated both positive and negative roles for cysLTs signaling through cysLTR1 during different helminth infection models. Absence of cysLTR1 during N. brasiliensis leads to delayed expulsion of adult worms and impaired recall of memory responses, indicating that cysteinyl leukotriene signaling via cysLTR1 is essential for orchestrating host protective responses. On the other hand, signaling via cysLTR1 appears to be dispensable for the development of host protective responses during acute schistosomiasis in mice. However, mice deficient of cysLTR1 had reduced liver pathology during chronic schistosomiasis, suggesting that inhibition of this receptor could be a potential therapy for reducing granulomatous liver pathology. 2021-09-14T14:27:06Z 2021-09-14T14:27:06Z 2021 2021-09-14T07:02:55Z Doctoral Thesis Doctoral PhD http://hdl.handle.net/11427/33872 eng application/pdf Department of Clinical Laboratory Sciences Faculty of Health Sciences
spellingShingle Clinical Science and Immunology
Mosala, Paballo Pertunia
The role of Cysteinyl leukotriene receptor-1 during experimental helminth infections in murine model
thesis_degree_str Doctoral
title The role of Cysteinyl leukotriene receptor-1 during experimental helminth infections in murine model
title_full The role of Cysteinyl leukotriene receptor-1 during experimental helminth infections in murine model
title_fullStr The role of Cysteinyl leukotriene receptor-1 during experimental helminth infections in murine model
title_full_unstemmed The role of Cysteinyl leukotriene receptor-1 during experimental helminth infections in murine model
title_short The role of Cysteinyl leukotriene receptor-1 during experimental helminth infections in murine model
title_sort role of cysteinyl leukotriene receptor 1 during experimental helminth infections in murine model
topic Clinical Science and Immunology
url http://hdl.handle.net/11427/33872
work_keys_str_mv AT mosalapaballopertunia theroleofcysteinylleukotrienereceptor1duringexperimentalhelminthinfectionsinmurinemodel
AT mosalapaballopertunia roleofcysteinylleukotrienereceptor1duringexperimentalhelminthinfectionsinmurinemodel