title: Investigation of red blood cell antigens with highly fluorescent and stable semiconductor quantum dots.
abstract: We report a new methodology for red blood cell antigen expression determination by a simple labeling procedure employing luminescent semiconductor quantum dots. Highly luminescent and stable core shell cadmium sulfide/cadmium hydroxide colloidal particles are obtained, with a predominant size of 9 nm. The core-shell quantum dots are functionalized with glutaraldehyde and conjugated to a monoclonal anti-A antibody to target antigen-A in red blood cell membranes. Erythrocyte samples of blood groups A+, A2+, and O+ are used for this purpose. Confocal microscopy images show that after 30 min of conjugation time, type A+ and A2+ erythrocytes present bright emission, whereas the O+ group cells show no emission. Fluorescence intensity maps show different antigen expressions for the distinct erythrocyte types. The results obtained strongly suggest that this simple labeling procedure may be employed as an efficient tool to investigate quantitatively the distribution and expression of antigens in red blood cell membranes.
authors.affiliation: Biofosica e Radiobiologia, Federal University of Pernambuco, Recife, Pernambuco, Brazil. pmaf@ufpe.br
authors.forename: Patrícia Maria Albuquerque
authors.initials: PM
authors.lastname: de Farias
authors.forename: Beate Saegesser
authors.initials: BS
authors.lastname: Santos
authors.forename: Frederico Duarte
authors.initials: FD
authors.lastname: de Menezes
authors.forename: Ricardo
authors.initials: R
authors.lastname: de Carvalho Ferreira
authors.forename: Maria Lourdes
authors.initials: ML
authors.lastname: Barjas-Castro
authors.forename: Vagner
authors.initials: V
authors.lastname: Castro
authors.forename: Paulo Roberto Moura
authors.initials: PR
authors.lastname: Lima
authors.forename: Adriana
authors.initials: A
authors.lastname: Fontes
authors.forename: Carlos Lenz
authors.initials: CL
authors.lastname: Cesar
mesh_terms: D001789:Blood Group Antigens / Q000097:blood*; D002478:Cells, Cultured; D004910:Erythrocyte Membrane / Q000276:immunology* / Q000648:ultrastructure*; D015200:Fluoroimmunoassay / Q000379:methods*; D006801:Humans; D018613:Microscopy, Confocal / Q000379:methods*; D008856:Microscopy, Fluorescence / Q000379:methods*; D045663:Quantum Dots; D012666:Semiconductors
chemical_list: D001789:Blood Group Antigens