Nnanna Isaiah Ibeh¹*, Onyiyechi Cynthia Okeke¹, Micheal Awo Okungbowa² and Isaiah Nnanna Ibeh³

¹Department of Veterinary Anatomy, Faculty of Veterinary Medicine, University of Benin, Nigeria
²Department of Physiology, Igbinedion University, Edo State, Nigeria
³Department of Medical Laboratory Science, School of Basic Medical Sciences, University of Benin, Nigeria

*Corresponding Author: Nnanna Isaiah Ibeh, Department of Veterinary Anatomy, Faculty of Veterinary Medicine, University of Benin, Nigeria.

Received: June 12, 2024; Published: July 15, 2024

Abstract

Background: Trypanosoma evansi, the parasite responsible for surra, a disease affecting livestock and occasionally humans, has evolved strategies to evade the host immune system. A key mechanism involves extracellular vesicles (EVs) that contain proteins and molecules impacting host immune cells. Understanding these interactions is essential for developing effective treatments.

Aim: This study explores how T. evansi-derived EVs affect the expression of immune-related proteins CD200 and AKT/TLR2 in host cells, aiming to understand their role in immune evasion.

Method: We used RAW 264.7 and THP-1 cell lines, stimulating them with T. evansi EVs for 24 to 72 hours. Flow cytometry assessed CD200 expression. Quantitative real-time polymerase chain reaction (qRT-PCR) measured the expression of CD200 and AKT/TLR2, while enzyme-linked immunosorbent assays (ELISA) quantified pro-inflammatory cytokines IL-6 and TNF-α.

Results: Flow cytometry showed a significant upregulation of CD200 after 72 hours of stimulation with T. evansi EVs. ELISA revealed elevated IL-6 and TNF-α levels, suggesting an inflammatory response to the EVs. qRT-PCR indicated increased expression of TLR2 and AKT.

Conclusion: The findings suggest that T. evansi EVs may contribute to immune evasion by upregulating CD200, which can suppress host immune responses. The simultaneous increase in IL-6 and TNF-α implies that immune pathways are activated, indicating a complex host response to T. evansi infection. These insights into the parasite's immune evasion tactics could guide the development of new therapeutic strategies for surra and other parasitic diseases. Further research into CD200's role in immune modulation is warranted.

 Keywords: Trypanosoma evansi; Extracellular Vesicles (EVs); Immune Evasion; CD200 Expression; Pro-inflammatory Cytokines; Host-Pathogen Interactions

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Citation

Citation: Nnanna Isaiah Ibeh., et al. “Exploring Immune Evasion Strategies: CD200 And ATK/TLR2 Upregulation in Response to Chronic T. evansi Vesicular Fraction Stimulation”.Acta Scientific Medical Sciences 8.8 (2024): 88-94.

Copyright

Copyright: © 2024 Nnanna Isaiah Ibeh., et al. This is an open-access article distributed under the terms of the Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original author and source are credited.