title: Caveolar endocytosis is required for human PSGL-1-mediated enterovirus 71 infection.
abstract: Enterovirus 71 (EV71) causes hand, foot, and mouth disease and severe neurological disorders in children. Human scavenger receptor class B member 2 (hSCARB2) and P-selectin glycoprotein ligand-1 (PSGL-1) are identified as receptors for EV71. The underling mechanism of PSGL-1-mediated EV71 entry remains unclear. The endocytosis required for EV71 entry were investigated in Jurkat T and mouse L929 cells constitutively expressing human PSGL-1 (PSGL-1-L929) or human rhabdomyosarcoma (RD) cells displaying high SCARB2 but no PSGL-1 by treatment of specific inhibitors or siRNA. We found that disruption of clathrin-dependent endocytosis prevented EV71 infection in RD cells, while there was no influence in Jurkat T and PSGL-1-L929 cells. Disturbing caveolar endocytosis by specific inhibitor or caveolin-1 siRNA in Jurkat T and PSGL-1-L929 cells significantly blocked EV71 infection, whereas it had no effect on EV71 infection in RD cells. Confocal immunofluorescence demonstrated caveola, and EV71 was directly colocalized. pH-dependent endosomal acidification and intact membrane cholesterol were important for EV71 infection, as judged by the pretreatment of inhibitors that abrogated the infection. A receptor-dominated endocytosis of EV71 infection was observed: PSGL-1 initiates caveola-dependent endocytosis and hSCARB2 activates clathrin-dependent endocytosis.
authors.affiliation: Institute of Infectious Disease and Vaccinology, National Health Research Institutes, Zhunan, Miaoli County, Taiwan.
authors.forename: Hsiang-Yin
authors.initials: HY
authors.lastname: Lin
authors.forename: Ya-Ting
authors.initials: YT
authors.lastname: Yang
authors.forename: Shu-Ling
authors.initials: SL
authors.lastname: Yu
authors.forename: Kuang-Nan
authors.initials: KN
authors.lastname: Hsiao
authors.forename: Chia-Chyi
authors.initials: CC
authors.lastname: Liu
authors.forename: Charles
authors.initials: C
authors.lastname: Sia
authors.forename: Yen-Hung
authors.initials: YH
authors.lastname: Chow
mesh_terms: D000818:Animals; D051242:Caveolin 1 / Q000378:metabolism; D002460:Cell Line; D004705:Endocytosis; D029821:Enterovirus A, Human / Q000502:physiology*; D055785:Gene Knockdown Techniques; D006801:Humans; D008562:Membrane Glycoproteins / Q000378:metabolism*; D051379:Mice; D018613:Microscopy, Confocal; D011991:Receptors, Virus / Q000378:metabolism*; D053586:Virus Internalization
chemical_list: D051242:Caveolin 1; D008562:Membrane Glycoproteins; C084882:P-selectin ligand protein; D011991:Receptors, Virus