title: Nanoscale organization of CD4 molecules of human T helper cell mapped by NSOM and quantum dots.
abstract: CD4 molecule, the surface marker of T helper cell, has been confirmed to be the main cellular receptor for the human immunodeficiency viruses HIV-1, HIV-2 and SIV. Recent research demonstrated the importance of the spatial arrangement of CD4 on the cell membrane to its binding efficiency to virus. In this article, the combined near-field scanning optical microscopy (NSOM) and quantum dots (QDs) fluorescent labeling technology were performed to investigate the nanoscale organization of CD4 molecules with a spatial resolution about 100 nm. Simultaneous topographic image of the T helper cell and fluorescent image of QDs have been directly gained by NSOM/QDs-based system. Intensity- and size-distribution histograms of the QDs fluorescent spots verify that approximately 80% of the CD4 molecules are organized in nanosized domains randomly distributed on the cell surface. Intensity-size correlation analysis revealed heterogeneity in the molecular packing density of the domains. Our results also illustrated the combination of NSOM imaging and QDs labeling is an ultrasensitive, high-resolution technique to probe nanoscale organization of molecules on the cell surface.
authors.affiliation: College of Life Science and Technology, Jinan University, Guangzhou, China.
authors.forename: Jianan
authors.initials: J
authors.lastname: Chen
authors.forename: Yangzhe
authors.initials: Y
authors.lastname: Wu
authors.forename: Chenxi
authors.initials: C
authors.lastname: Wang
authors.forename: Jiye
authors.initials: J
authors.lastname: Cai
mesh_terms: D000954:Antigens, Surface / Q000378:metabolism; D015704:CD4 Antigens / Q000378:metabolism*; D006801:Humans; D020527:Microscopy, Scanning Probe / Q000295:instrumentation* / Q000379:methods*; D036103:Nanotechnology / Q000295:instrumentation*; D045663:Quantum Dots; D006377:T-Lymphocytes, Helper-Inducer / Q000378:metabolism* / Q000648:ultrastructure
chemical_list: D000954:Antigens, Surface; D015704:CD4 Antigens