DefinePK

Abstract

Background & objective: Patients with chronic myeloid leukemia (CML) are at risk of Hepatitis B Virus (HBV) reactivation during tyrosine kinase inhibitor (TKI) therapy. Programmed death-ligand 1 (PD-L1) polymorphisms may influence immune evasion and disease pathogenesis; however, their interaction with HBV in CML, particularly in Iraqi population, remains uncharacterized. This study aimed to investigate PD-L1 genetic variations, serum PD-L1 levels, and HBV infection.
Methodology: It was a case-control study of 120 patients with CML and 100 apparently healthy controls (AHC). Serum PD-L1 and HBV markers were quantified by Enzyme-Linked Immunosorbent Assay (ELISA), Genomic DNA was extracted, and specific regions of the PD-L1 gene and HBV DNA were amplified by polymerase chain reaction (PCR). PD-L1 amplicons were sequenced to identify genetic variants.
Results: CML patients exhibited significantly lower serum PD-L1 levels than controls (mean 268.8 ± 89 vs. 470.6 ± 288, P = 0.0032). No HBV DNA was detected in any participant. A novel C>T substitution in PD-L1 was identified, with TT and CT genotypes being more frequent in CML patients than in controls. The T allele showed a borderline significant association with a reduced CML risk (P = 0.01, OR=0.22, 95% CI: 0.06–0.73).
Conclusion: The PD-L1 T allele may confer protection against CML, while suppression of serum PD-L1 suggests distinct regulatory mechanisms. The absence of HBV highlights regional epidemiological patterns. PD-L1 genotyping can inform risk stratification of patients with Iraqi CML.
Abbreviations: AHC: apparently healthy controls, CML: chronic myeloid leukemia, ELISA: Enzyme-Linked Immunosorbent Assay, HBV: Hepatitis B virus, HSC: hematopoietic stem cell, PD-L1: Programmed death-ligand 1,
Keywords: Chronic Myeloid Leukemia; Programmed Death-Ligand 1; Hepatitis B Virus; Immune Checkpoint
Citation: Hassan DO, Jawad AH, Al. Alwany SHM. Immunogenetic study of programmed death-ligand 1 variation and hepatitis B virus in Iraqi patients with chronic myeloid leukemia. Anaesth. pain intensive care 2025;29(6):573-580. DOI: 10.35975/apic.v29i6.2917
Received: June 12, 2025; Revised: July 09, 2025; Accepted: July 10, 2025