Soluble HLA-G Molecules Are Increased during Acute Leukemia, Especially in Subtypes Affecting Monocytic and Lymphoid Lineages'

• Main Authors: Frédéric Gros, Yasmine Sebti, Sophie de Guiber, Bernard Branger, Marc Bernard, Renée Fauchet, Laurence Amiot
• Format: Article
• Language: English
• Published: Elsevier 2006-03-01
• Series: Neoplasia: An International Journal for Oncology Research
• Subjects: Soluble human leukocyte antigen G (sHLA-G); acute myeloblastic leukemia (AML); acute lymphoblastic leukemia (ALL); myelodysplasia; immunomodulation
• Online Access: http://www.sciencedirect.com/science/article/pii/S1476558606800515
• ISSN: 1476-5586; 1522-8002

Human leukocyte antigen G (HLA-G) molecules corresponding to nonclassic class I genes of the major histocompatibility complex exhibit immunomodulatory properties. They are either membrane-bound or solubly expressed during certain tumoral malignancies. Soluble human leukocyte antigen G (sHLA-G) molecules seem more frequently expressed than membranebound isoforms during hematologic malignancies, such as lymphoproliferative disorders. Assay of these molecules by enzyme-linked immunosorbent assay in patients suffering from another hematologic disorder (acute leukemia) highlights increased sHLA-G secretion. This increased secretion seems more marked in acute leukemia subtypes affecting monocytic and lymphoid lineages such as FABM4 and FABM5, as well as both B and T acute lymphoblastic leukemia (ALL). Moreover, this study uses in vitro cytokine stimulations and reveals the respective potential roles of granulocyte-macrophage colony-stimulating factor and interferon-γ in increasing this secretion in FABM4 and ALL. Correlations between sHLA-G plasma level and clinical biologic features suggest a link between elevated sHLA-G level and 1) the absence of anterior myelodysplasia and 2) high-level leukocytosis. All these findings suggest that sHLA-G molecules could be a factor in tumoral escape from immune survey during acute leukemia.