title: A novel high throughput quantum dot-based fluorescence assay for quantitation of virus binding and attachment.
abstract: Quantum dots (QDots) are fluorescent semiconductor nanocrystals with a narrow emission spectrum, high quantum yield, and excellent photostability. These unique properties of QDots have been utilized to develop a fluorescent binding assay using biotinylated human T cell leukemia virus type 1 (biot-HTLV-1) conjugated with streptavidin-coated QDots that enabled both qualitative and quantitative analyses of viral binding. The specificity and linearity of the assay was demonstrated utilizing T cells, the primary HTLV-1-susceptible cell population. Furthermore, differential binding of HTLV-1 was analyzed in additional cell types of clinical relevance including primary CD4(+) and CD8(+) T cells, dendritic cells (DCs), monocytes, bone marrow progenitor cells, and epithelial cells. DCs exhibited maximum binding affinity when compared to other examined cell types except the Jurkat and SUP-T1 T cell lines. Finally, blocking antibodies directed against a putative HTLV-1 receptor on DCs; DC-SIGN (dendritic cell-specific ICAM-3-grabbing non-integrin), were utilized to study the inhibition of HTLV-1 binding to target cells. Overall, these results demonstrated that this novel high throughput assay can be utilized to study the binding of a biotinylated virus and has implications for screening of viral binding inhibitors as well as host membrane proteins that may serve as receptors for viral entry.
authors.affiliation: Department of Microbiology and Immunology, Institute for Molecular Medicine and Infectious Disease, Center for Molecular Virology and Neuroimmunology, Center for Cancer Biology, Drexel University College of Medicine, Philadelphia, PA 19102, USA.
authors.forename: Karan
authors.initials: K
authors.lastname: Kampani
authors.forename: Kevin
authors.initials: K
authors.lastname: Quann
authors.forename: Jaya
authors.initials: J
authors.lastname: Ahuja
authors.forename: Brian
authors.initials: B
authors.lastname: Wigdahl
authors.forename: Zafar K
authors.initials: ZK
authors.lastname: Khan
authors.forename: Pooja
authors.initials: P
authors.lastname: Jain
mesh_terms: D019921:Biotinylation; D002460:Cell Line; D002478:Cells, Cultured; D005453:Fluorescence; D015368:Human T-lymphotropic virus 1 / Q000502:physiology*; D006801:Humans; D007963:Leukocytes, Mononuclear; D018613:Microscopy, Confocal / Q000379:methods*; D045663:Quantum Dots; D053585:Virus Attachment