Hamadan University of Medical Sciences Avicenna Journal of Dental Research 2423-7582 18 2 2026 06 30 Comparison of Salivary Levels of Adenosine Deaminase and Interleukin-10 in COVID-19 Vaccine Recipients and Non-Vaccinated Individuals 81 86 10.34172/ajdr.5636 EN Yasamin Barakian https://orcid.org/0000-0001-9860-9313 Sara Nouriani https://orcid.org/0009-0004-2051-2393 Mohammad Ebrahim Ghaffari https://orcid.org/0000-0002-8301-8710 Fatemeh Ahmadi-Motamayel https://orcid.org/0000-0002-7138-7690 Journal Article 10.34172/ajdr.5636 2025 11 02 2026 06 08 Introduction: Global efforts to combat COVID-19 have led to the rapid development and widespread administration of various vaccines, including AstraZeneca. While vaccination remains a pivotal strategy for controlling the virus’s spread, it is crucial to explore its potential immunomodulatory effects on salivary biomarkers. Adenosine deaminase (ADA) and interleukin-10 (IL-10), both implicated in immune responses, serve as vital indicators of the host’s immune status. ADA is a marker related to purine metabolism and cellular immune activity, while IL-10 is a regulatory cytokine involved in limiting inflammatory responses. Therefore, this study aimed to compare the salivary levels of ADA and IL-10 between COVID-19–vaccinated and unvaccinated individuals. Methods: Overall, 41 individuals with a history of at least two doses of the AstraZeneca vaccine and 41 unvaccinated individuals were included in this case-control study. Non-stimulated saliva samples were collected in sterile test tubes. Then, IL-10 levels in the saliva were measured by the enzyme-linked immunosorbent assay, and the total amount of ADA in the saliva was calculated using specific ADA kits. Finally, data were analyzed by SPSS 28 using ANCOVA test (P=0.05). Results: The average ADA level was higher in COVID-19 vaccine recipients (20.26±3.20) than in unvaccinated individuals (18.37±2.12). Moreover, the average IL-10 level was higher in the vaccinated group (31.05±8.32) compared to the unvaccinated group (21.12±9.50). Conclusion: AstraZeneca vaccination could alter the immune system’s homeostasis compared to unvaccinated individuals. Our findings confirmed that COVID-19 vaccination significantly increases salivary IL-10 and ADA levels in vaccine recipients.