Pulmonary Hydatid Infection (Echinococcus granulosus larvae) as a Possible Inducer of Alveolar Adenocarcinoma and Immune Cell Response in Ovine Lung Tissue

Document Type : Original Articles

Authors

1 Department of Biology, College of Sciences, Diyala University, Baqubah, Iraq.

2 Department of Biology, College of Education for Pure Sciences, University of Diyala, Baqubah, Iraq.

10.32598/ijvm.20.3.1005866

Abstract

Background: Pulmonary hydatidosis infection, caused by Echinococcus granulosus larvae, is a zoonotic disease that stimulates remarkable histological and immunological alterations in infected host tissues.
Objectives: This study investigated the link between hydatid infection and alveolar adenocarcinoma in sheep lungs, alongside the localized immune response, including CD4+ and CD8+ T cells and PD-L1 expression. 
Methods: A total of 24 hydatid-infected and 10 non-infected ovine lung samples were examined using histopathological (H&E, PAS, Masson’s trichrome) and immunohistological (CD4, CD8, and PD-L1) techniques. 
Results: Results demonstrated that 36% of infected lungs revealed adenocarcinoma, accompanied by notable inflammation, necrosis, and fibrosis. Immunohistological tests demonstrated an increase in CD4+ and CD8+ T-cell infiltration in infected tissues, with PD-L1 expression significantly higher in adenocarcinoma-associated samples compared to non-infected and hydatid-only lungs. 
Conclusion: These results suggest that chronic hydatid infection may contribute to oncogenic transformation through modulation of immune response, particularly via exhaustion of PD-L1-mediated T-cells. This study also highlights the possible role of E. granulosus in pulmonary carcinogenesis and emphasizes the importance role of immune checkpoint molecules in parasitic and neoplastic evasion mechanisms.

Keywords

Iranian Journal of Veterinary Medicine
Volume 20, Issue 3
May and June 2026
Pages 563-576

Files

Share

How to cite

Statistics