Detection of dying cells using lectin‐conjugated fluorescent and luminescent nanoparticles

Abstract

Constantly increasing sector of industry of biomedical diagnostics requires photosensitive and stable nanomaterials which can be specifically bio-labeled for targeting selected cells in the body. Here we describe two types of novel nanomaterials conjugated with specific proteins recognized by dying (apoptotic and necrotic) cells. They are luminescent GaN:Eu 3+ -doped nanoparticles with wide green emission and very narrow red emission and fluorescent green-emitting fluorescein-containing polystyrene nanoparticles. These nanoparticles were conjugated with carbohydrate recognizing proteins -the lectins -that are targeting specific cell surface glycoproteins which were recently shown to be novel markers of dying cells (Bilyy et al., 2003, Bilyy et al., 2007. Both luminescent and fluorescent nanoparticles possessed high brightness and low level of photobleaching and efficiently interacted with dying cells, thus discriminating them from the intact ones.

Sweet taste of cell death: role of carbohydrate recognition systems

“…β-D-galactose specific lectins isolated from Ricinus communis (RCA) and Viscum album (VAA), were also better bound to the apoptotic cells [32]. At the same time, binding of α2,3-sialic-specific MAA-II lectin with the surface of apoptotic cells was decreased (demonstrated by Azuma et al [33], Batisse et al [34], as well as our group [35]). Similar apoptosis-related decrease in binding of α2,6-sialil-specific lectin SNA isolated from Sambucus nigra, was shown in U-937 cells [34], but not in Jurkat T-cells [33].…”

Oligomannose-Rich Membranes of Dying Intestinal Epithelial Cells Promote Host Colonization by Adherent-Invasive E. coli

“…Confocal microscopy was performed using a Carl Zeiss LSM 780 microscope equipped with five lasers (405, 458, 488, 514, and 633 nm). Fluorescent labeling of lectins was done according to the general principles of lectin chemistry and bioconjugate techniques, as described (Bilyy et al, 2009 ).…”

Magnetic separation of apoptotic cells with lectin‐conjugated microparticles

“…Desialylated and oligomannose glycans are other markers of apoptotic cells reported by us few years ago . Lectin‐conjugated nano‐ and microparticles, recognizing corresponding apoptotic glycans were effectively exploited to detect dying cells . We have demonstrated that phosphatidylserine and its receptors on macrophages; desialylated glycans and asialoglycoprotein macrophageal receptors; oligomannose glycans and mannose specific macrophageal receptors acts as three independent recognitions pairs, and there is a complementary effect among pairs during the clearance of dying (apoptotic) cells .…”