Immunophenotypic and IL-17 Genetic Evaluation in Iraqi Patients with Chronic Myeloid Leukemia

This study was designed to shed light on the association between the genetic variations in IL-17A and IL-17F genes, and their levels in chronic myeloid leukemia (CML).Sixty two patients (38 males, and 24 females), with an age range 21 – 73 years old, were diagnosed with chronic myeloid leukemia, and 28 healthy individuals (18 males and 10 females), with an age range 24 – 72 years old, were enrolled in this study. Blood samples were collected from Oncology Teaching Hospital and Baghdad Teaching Hospital – Baghdad Medical City, and National Center of Blood diseases – Al-Mustansiriya University.
Cytokine gene polymorphism analysis by sequencing revealed 13 registered variants for IL-17A exon 1; the rs199815459 SNP in IL-17A exon 1, which linked specifically to the CML with a genotype TG while healthy subject showed a GG genotype. The rs749745973 detected with GA genotype with (100%) frequency in CML and healthy unlike the registered genotype, which was GC. Also, results showed some unregistered genetic variations detected in IL-17A exon1, first one was in the promoter, the second and third variations were recorded in the coding sequence, while the last one was an intronic variation. These variations were detected in CML and healthy. IL-17F exon 3 sequencing results showed a registered rs2397084, which was found in AG genotype in (9.1%) frequency in CML and AA genotypes which was detected in CML with frequency (90.9%) and (100%) in healthy.Also, serum level of IL-17A and IL-17F were estimated by ELISA.  Results exhibited IL-17A level in newly diagnosed recorded a significant elevation in comparing with healthy individuals, while the level was significantly lower in noncomplete treatment patients compared with healthy individuals (P≤0.05). Serum IL-17F levels in newly diagnosed showing a significant increase while the under treatment patients showed a significant lower level compared with pretreated.Also, immunophenotypic features of CD4+ and CD8+ were calculated by flow cytometer in this study. Results revealed CD4 and CD8 count in newly diagnosed and under treatment CML patients’ blood was also different from the healthy, giving a significant increase count in newly diagnosed patients and a significant decrease count in non-complete treatment patients.