Abstract
Infectious mononucleosis (IM), a common disease in children, was often accompanied by excessive inflammatory response and organ damage. This study aimed to explore the CD26/ADA axis in the pathogenesis of acute Epstein-Barr virus (EBV)-associated IM. Thirty children with acute IM and thirty age-matched controls from Children’s Hospital of Soochow University were enrolled in this study. The CD26 and adenosine deaminase (ADA) mRNA were detected by real-time PCR in the peripheral blood. Meanwhile, the levels of plasma interferon gamma (IFN-γ), interleukin (IL)-4 and IL-10 were measured by ELISA, and the frequency of CD26-positive cells in CD4+ T cells and CD8+ T cells was analyzed by flow cytometry. Children with acute IM had significantly higher expression levels of CD26 mRNA and ADA mRNA than control group in peripheral blood (P < 0.05). Plasma IL-4, IL-10 and INF-γ level were markedly elevated compared to the control group (P < 0.05). Furthermore, the plasma CD26 protein level was positively correlated with ADA (r = 0.610, P<0.01) and INF-γ (r = 0.417, P = 0.022), and negatively correlated with the percentage of CD3+ CD4+ T cell (r = -0.446, P = 0.014) and CD4+ /CD8+ ratio (r = -0.414, P = 0.023) in acute IM group. In addition, the frequency of CD26-positive cells was elevated on CD8+ T cells but markedly decreased on CD4+ CD39+ regulatory T cells (P < 0.05). The peripheral blood CD26 and ADA mRNA levels were elevated in acute IM. Moreover, CD26 exhibited cell-specific alterations, being increased on CD8+ T cells but reduced on CD4+ CD39+ Tregs.
Data availability
The datasets generated during and/or analyzed during the current study are available from the corresponding author on reasonable request.
Abbreviations
- IM:
-
Infectious mononucleosis
- IFN-γ,:
-
Interferon gamma
- IL-4:
-
Interleukin-4
- EBV:
-
Epstein-Barr virus
- HLH:
-
Hemophagocytic lymphohistiocytosis
- ADA:
-
Adenosine deaminase
- VCA:
-
Capsid antigen
- EBNA:
-
Nuclear antigen
- APC:
-
Allophycocyanin
- PE:
-
phycoerythrin
- FITC:
-
Fluorescein isothiocyanate
- WBC:
-
Peripheral blood white blood cell
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Funding
This study was supported by the Science and Technology Project of Suzhou, China (2023ZDPY03).
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TS and WS collected data; LH analyzed and interpreted data; TS wrote the manuscript; WS prepared figures and tables; LH and JT revised critically the manuscript. All authors reviewed the manuscript.
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This study adheres to the ethical principles of the Declaration of Helsinki. It was approved by the Ethics Committee of Children’s Hospital of Soochow University (No.2023CS059). Given the pediatric population, special protections for child participants were implemented: Written informed consent was obtained from the legal guardians of all children, and additional verbal assent was obtained from children aged ≥ 7 years. The informed consent form was specifically revised to include: (i) explicit statements that only residual clinical specimens/routine data would be used to avoid additional procedures; (ii) clear emphasis on the child’s right to refuse participation or withdraw at any time without affecting clinical care; (iii) detailed description of data anonymization and privacy protection measures; (iv) contact information for an independent pediatrician (unaffiliated with the research team) for consultation regarding child participants’ rights.
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Shi, T., Shi, W., Tian, J. et al. Altered expression of the CD26/ADA axis in immune-mediated inflammation of infectious mononucleosis. Sci Rep (2026). https://doi.org/10.1038/s41598-026-38891-z
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DOI: https://doi.org/10.1038/s41598-026-38891-z
