Contributions
Abstract: PB1856
Type: Publication Only
Background
CD177 is a glycosyl-phosphatidylinositol (GPI)-linked cell surface glycoprotein that has been shown to be a counter-receptor for platelet endothelial cell adhesion molecule-1 (PECAM-1). The interaction of CD177 with endothelial PECAM-1 supports neutrophil transendothelial migration. The phenotype of neutrophils can change in patients with malignant diseases of the hematopoiesis system. Several studies have confirmed the overexpression of neutrophil CD177 mRNA in polycythemia rubra vera, and two other myleoproliferative disorders, essential thrombocythemia and idiopathic myelofibrosis. It was also shown that CD177 is absent from neutrophils from paroxysmal nocturnal hemoglobinurea patients who are deficient in the ability to synthesize GPI linkages. Neutrophils from patients with chronic lymphoproliferative diseases (CLD) are characterized by increased CD54 expression, which is associated with cell activation. Little is known about the level of CD177 expression in patients with CLD.
Aims
The aim of the study was to evaluate and compare the expression level of CD 177 in donors and patients with CLD and myeloid neoplasias (MNP).
Methods
Blood samples of 144 healthy donors (group 1), 94 patients with CLD: chronic lymphocytic leukemia, Hodgkin's lymphomas, non-Hodgkin's lymphomas, multiple myeloma patients (group 2), and 61 patients with MNP, including chronic idiopathic myelofibrosis, chronic myelogenous leukemia, essential thrombocytosis, polycythemia vera patients (group 3) were included in the study. The mean age of patients in groups 2 and 3 was 64 years (range, 22 to 84) and 65 years (range, 21 to 81), respectively. Flow cytometry immunophenotyping analysis of CD 177 was performed using anti-human CD 177-PE, clone MEM-166. The level of CD177 expression was evaluated using mean fluorescence intensity (MFI) rate. MFI for CD 177-PE in group 1 was taken as the reference value.
Results
MFI for anti-CD 177-PE in group 1 was 31.8 to 149 (median 79.2). MFI in groups 2 and 3 was significantly higher (p = 0.000001) than in group 1 (median 114, CI: 38.58 - 706.7 and median 131.1, CI: 40.39-360.2 vs median 79.2, CI: 41.25-136.37, respectively). No significant differences were revealed when MFI between groups 2 and 3 were compared (p = 0.19).
Conclusion
The expression level of CD 177 is increased in patients with CLD and MNP compared to healthy donors. Neutrophils in patients with CLD have an activated phenotype, probably associated with a systemic inflammation. The presence of a chronic systemic inflammatory response may also explain the increase in CD 177 expression in patients with MNP.
Session topic: 5. Chronic lymphocytic leukemia and related disorders – Biology & Translational Research
Abstract: PB1856
Type: Publication Only
Background
CD177 is a glycosyl-phosphatidylinositol (GPI)-linked cell surface glycoprotein that has been shown to be a counter-receptor for platelet endothelial cell adhesion molecule-1 (PECAM-1). The interaction of CD177 with endothelial PECAM-1 supports neutrophil transendothelial migration. The phenotype of neutrophils can change in patients with malignant diseases of the hematopoiesis system. Several studies have confirmed the overexpression of neutrophil CD177 mRNA in polycythemia rubra vera, and two other myleoproliferative disorders, essential thrombocythemia and idiopathic myelofibrosis. It was also shown that CD177 is absent from neutrophils from paroxysmal nocturnal hemoglobinurea patients who are deficient in the ability to synthesize GPI linkages. Neutrophils from patients with chronic lymphoproliferative diseases (CLD) are characterized by increased CD54 expression, which is associated with cell activation. Little is known about the level of CD177 expression in patients with CLD.
Aims
The aim of the study was to evaluate and compare the expression level of CD 177 in donors and patients with CLD and myeloid neoplasias (MNP).
Methods
Blood samples of 144 healthy donors (group 1), 94 patients with CLD: chronic lymphocytic leukemia, Hodgkin's lymphomas, non-Hodgkin's lymphomas, multiple myeloma patients (group 2), and 61 patients with MNP, including chronic idiopathic myelofibrosis, chronic myelogenous leukemia, essential thrombocytosis, polycythemia vera patients (group 3) were included in the study. The mean age of patients in groups 2 and 3 was 64 years (range, 22 to 84) and 65 years (range, 21 to 81), respectively. Flow cytometry immunophenotyping analysis of CD 177 was performed using anti-human CD 177-PE, clone MEM-166. The level of CD177 expression was evaluated using mean fluorescence intensity (MFI) rate. MFI for CD 177-PE in group 1 was taken as the reference value.
Results
MFI for anti-CD 177-PE in group 1 was 31.8 to 149 (median 79.2). MFI in groups 2 and 3 was significantly higher (p = 0.000001) than in group 1 (median 114, CI: 38.58 - 706.7 and median 131.1, CI: 40.39-360.2 vs median 79.2, CI: 41.25-136.37, respectively). No significant differences were revealed when MFI between groups 2 and 3 were compared (p = 0.19).
Conclusion
The expression level of CD 177 is increased in patients with CLD and MNP compared to healthy donors. Neutrophils in patients with CLD have an activated phenotype, probably associated with a systemic inflammation. The presence of a chronic systemic inflammatory response may also explain the increase in CD 177 expression in patients with MNP.
Session topic: 5. Chronic lymphocytic leukemia and related disorders – Biology & Translational Research