Pathogen-specific kinetics of oxidative burst in camel leukocytes: Influence of serum opsonization on reactive oxygen species production

Vet World Vol.18 August-2025 Article - 9

Research Article

Veterinary World, 18(8): 2252-2263

https://doi.org/10.14202/vetworld.2025.2252-2263

Salma Al Adwani¹

, Nardin Al Kindi¹, Abeer Al Hamrashdi¹, Samir Al Bulushi²

, Salim M Al Hajri²

, Jamal Hussen³

, Waleed Al Marzooqi¹

, and Yasmin El Tahir¹

1. Department of Animal and Veterinary Sciences, Sultan Qaboos University, Muscat, Oman.

2. Laboratories and Animal Research Center, Directorate General of Veterinary Services, Royal Court Affairs, Muscat, Sultanate of Oman.

3. Department of Microbiology, College of Veterinary Medicine, King Faisal University, Al-Ahsa, Saudi Arabia.

Background and Aim: Dromedary camels exhibit unique immune adaptations that enable survival in harsh environments with high microbial exposure. However, the cellular mechanisms underpinning their innate immune responses, particularly oxidative respiratory bursts, remain underexplored. This study aimed to investigate the kinetics of reactive oxygen species (ROS) production in camel leukocytes in response to selected bacterial and fungal pathogens and to assess the effect of serum opsonization on ROS generation.

Materials and Methods: Whole blood from six clinically healthy female dromedary camels was stimulated with opsonized and non-opsonized Staphylococcus aureus, Pseudomonas aeruginosa, Escherichia coli, Klebsiella pneumoniae (three strains), and Candida albicans. Luminol-enhanced chemiluminescence (CL) assays were used to quantify ROS production over a 3-h period. Colony-forming units were evaluated to confirm microbial viability post-opsonization. Key ROS metrics included area under the curve, peak emission (relative light unit), and time to peak.

Results: Camel neutrophils demonstrated distinct pathogen-specific ROS kinetics. P. aeruginosa and K. pneumoniae 1705 elicited the highest total ROS on serum opsonization, whereas S. aureus and C. albicans showed minimal ROS induction. E. coli failed to induce a measurable ROS response. Serum opsonization significantly enhanced total ROS production and shortened peak response time for K. pneumoniae strains. In contrast, it reduced total ROS output for S. aureus and C. albicans without significantly affecting their peak kinetics.

Conclusion: This study provides the first comprehensive analysis of microbial-specific ROS production in camel whole blood using a luminol-based CL assay. The findings underscore the variability in camel innate immune responses to different pathogens and highlight the modulatory role of serum opsonization. These insights could inform future strategies in camel immunotherapy, vaccine development, and disease diagnostics.

Keywords: Camelus dromedaries, luminol chemiluminescence, microbial pathogens, neutrophils, oxidative burst, reactive oxygen species, serum opsonization.

How to cite this article: Adwani SA, Kindi NA, Hamrashdi AA, Bulushi SA, Hajri SMA, Hussen J, Marzooqi WA, and Tahir YE (2025) Pathogen-specific kinetics of oxidative burst in camel leukocytes: Influence of serum opsonization on reactive oxygen species production, Veterinary World, 18(8): 2252-2263.

Received: 09-04-2025 Accepted: 27-06-2025 Published online: 09-08-2025

Corresponding author: Salma Al Adwani E-mail: aladwani@squ.edu.om

DOI: 10.14202/vetworld.2025.2252-2263

Copyright: Adwani, et al. This article is an open access article distributed under the terms of the Creative Commons Attribution 4.0 International License (http://creativecommons.org/licenses/by/4.0/), which permits unrestricted use, distribution, and reproduction in any medium, provided you give appropriate credit to the original author(s) and the source, provide a link to the Creative Commons license, and indicate if changes were made. The Creative Commons Public Domain Dedication waiver (http:// creativecommons.org/publicdomain/zero/1.0/) applies to the data made available in this article, unless otherwise stated.