This study was designed to assess the binding of glycophorin A-specific antibodies to polyethylene glycol (PEG)-modified red blood cells (RBCs) and evaluate their resistance to invasion by Plasmodium falciparum malaria parasites. RBCs were conjugated with a range of concentrations (0.05 to 7.5 mM) of activated PEG derivatives of either 3.35 or 18.5 kd molecular mass. The binding of glycophorin A-specific antibodies was assessed by hemagglutination and flow cytometry. PEG-modified RBCs were assessed for their ability to form rosettes around Chinese hamster ovary (CHO) cells transiently expressing the glycophorin A binding domain of EBA-175, a P falciparum ligand crucial to RBC invasion. PEG-RBCs were also tested for their ability to be invaded by the malaria parasite. RBCs coated with 3.35 and 18.5 kd PEG demonstrated a dose-dependent inhibition of glycophorin A-specific antibody binding, CHO cell rosetting, and P falciparum invasion. These results indicate that glycophorin A epitopes responsible for antibody and parasite binding are concealed by PEG coating, rendering these cells resistant to P falciparum invasion. These studies confirm the effectiveness of PEG modification for masking RBC-surface glycoproteins. This may provide a means to prevent alloimmunization in the setting of RBC transfusion and suggests a novel method to enhance the effectiveness of exchange transfusion for the treatment of cerebral malaria.
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http://dx.doi.org/10.1182/blood.v97.2.551 | DOI Listing |
Acute monoblastic leukemia (AMoL) is characterized by cells with highly undifferentiated morphology. Cytochemistry with non-specific esterases is negative in up to 20% of cases. Immunophenotyping by flow cytometry has an essential role in diagnosing such a subtype of leukemia and a multiparametric approach with a wide monoclonal antibody panel is necessary.
View Article and Find Full Text PDFFASEB J
February 2018
Cellular Signalling Laboratory, Institute of Human Anatomy, Dipartimento di Scienze Biomediche e NeuroMotorie, University of Bologna, Bologna, Italy.
PI-PLCβ1 is involved in cell proliferation, differentiation, and myelodysplastic syndrome (MDS) pathogenesis. Moreover, the increased activity of PI-PLCβ1 reduces the expression of PKC-α, which, in turn, delays the cell proliferation and is linked to erythropoiesis. Lenalidomide is currently used in low-risk patients with MDS and del(5q), where it can suppress the del(5q) clone and restore normal erythropoiesis.
View Article and Find Full Text PDFBiophys J
August 2017
Department of Structural Engineering, University of California, San Diego, La Jolla, California. Electronic address:
Prospects of vesiculation occurring during splenic flow of erythrocytes are addressed via model simulations of RBC flow through the venous slits of the human spleen. Our model is multiscale and contains a thermally activated rate-dependent description of the entropic elasticity of the RBC spectrin cytoskeleton, including domain unfolding/refolding. Our model also includes detail of the skeleton attachment to the fluidlike lipid bilayer membrane, including a specific accounting for the expansion/contraction of the skeleton that may occur via anchor protein diffusive motion, that is, band 3 and glycophorin, through the membrane.
View Article and Find Full Text PDFZhongguo Shi Yan Xue Ye Xue Za Zhi
August 2016
Department of Hematology, Affiliated Hospital of Qinghai University, Xining 810001, Qinghai Province, China.
Unlabelled: Objective: To study the effect of PD98059, a specific inhibitor of Ras/Raf/MEK/ERK signaling pathway, on the proliferation and apoptisis of bone marrow CD71(+), CD235a(+) nucleated erythrocytes in patients with high altitude polycythemia (HAPC) and the pathogenesis of HAPC.
Methods: The CD71(+) and CD235a(+) nucleated erythrocytes in HAPC patients and controls (patients with simple obsolete stracture) were sorted by using the immunemagnetic beads, then were added with 5, 10, 20 µmol/L of PD98059 and DMSO (as control) and were cultured for 72 h under hypoxia. The cell apoptosis was detected by flow cytometry with Annexin V and PI double staining, the cell proliferation was detected by CCK8 method, at same time the erythroid colong-formation ability of bone marrow mononuclear cells (BMMNC) treated with 5, 10, 20 µmol/L of PD98059 and DMSO was observed.
Med Mol Morphol
March 2016
Department of Anatomy and Molecular Histology, Interdisciplinary Graduate School of Medicine and Engineering, University of Yamanashi, 1110 Shimokato, Chuo City, Yamanashi, Japan.
Membrane skeletal networks form a two-dimensional lattice structure beneath erythrocyte membranes. 4.1R-MPP (membrane palmitoylated protein) 1-glycophorin C is one of the basic molecular complexes of the membrane skeleton.
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