Abstract
Background Chronic myeloid leukemia (CML) cells can suppress the immune system by secreting programmed death receptor ligand-1 (PDL-1) that acts as a coinhibitory molecule for T cells leading to T-cell exhaustion and disease progression.
Aim The aim of this study was to assess the plasma level of PDL-1 in patients with chronic myelogenous leukemia and its correlation with prognostic parameters and response to first-line therapy.
Patients and methods This study was carried out on 40 patients with CML in chronic phase and 40 control healthy participants. Patients with CML were subdivided into three subgroups, including 11 newly diagnosed patients, 17 imatinib mesylate-responding patients, and 12 imatinib-resistant cases. All patients were subjected to laboratory investigations including complete blood count, peripheral blood smear examination, bone marrow aspiration (if indicated), quantitative real-time PCR for Philadelphia chromosome, and plasma PDL-1 measurement by enzyme-linked immune sorbent assay.
Results Our results showed high plasma levels of PDL-1 in patients with CML. Plasma PDL-1 levels showed a negative correlation with total lymphocyte count in imatinib-resistant subgroup. Imatinib-resistant subgroup showed a significant decreased level of PDL-1 versus newly diagnosed subgroup of patients with CML. The suggested PDL-1 cut-off value for prediction of patients with CML was 1327.5 ng/l.
Conclusion Patients with chronic-phase CML (newly diagnosed, imatinib responding, and imatinib resistant) showed a highly significant increased PDL-1 level compared with the control group. Increased plasma PDL-1 level is a predictive risk factor for CML incidence and disease progression. (c) 2018 The Egyptian Journal of Haematology.