6ce0
From Proteopedia
Crystal structure of a HIV-1 clade B tier-3 isolate H078.14 UFO-BG Env trimer in complex with broadly neutralizing Fabs PGT124 and 35O22 at 4.6 Angstrom
Structural highlights
FunctionQ2N0S5_9HIV1 The envelope glyprotein gp160 precursor down-modulates cell surface CD4 antigen by interacting with it in the endoplasmic reticulum and blocking its transport to the cell surface.[RuleBase:RU004292][SAAS:SAAS00139820] The gp120-gp41 heterodimer allows rapid transcytosis of the virus through CD4 negative cells such as simple epithelial monolayers of the intestinal, rectal and endocervical epithelial barriers. Both gp120 and gp41 specifically recognize glycosphingolipids galactosyl-ceramide (GalCer) or 3' sulfo-galactosyl-ceramide (GalS) present in the lipid rafts structures of epithelial cells. Binding to these alternative receptors allows the rapid transcytosis of the virus through the epithelial cells. This transcytotic vesicle-mediated transport of virions from the apical side to the basolateral side of the epithelial cells does not involve infection of the cells themselves.[SAAS:SAAS00140087] Publication Abstract from PubMedOvercoming envelope metastability is crucial to trimer-based HIV-1 vaccine design. Here, we present a coherent vaccine strategy by minimizing metastability. For 10 strains across five clades, we demonstrate that the gp41 ectodomain (gp41ECTO) is the main source of envelope metastability by replacing wild-type gp41ECTO with BG505 gp41ECTO of the uncleaved prefusion-optimized (UFO) design. These gp41ECTO-swapped trimers can be produced in CHO cells with high yield and high purity. The crystal structure of a gp41ECTO-swapped trimer elucidates how a neutralization-resistant tier 3 virus evades antibody recognition of the V2 apex. UFO trimers of transmitted/founder viruses and UFO trimers containing a consensus-based ancestral gp41ECTO suggest an evolutionary root of metastability. The gp41ECTO-stabilized trimers can be readily displayed on 24- and 60-meric nanoparticles, with incorporation of additional T cell help illustrated for a hyperstable 60-mer, I3-01. In mice and rabbits, these gp140 nanoparticles induced tier 2 neutralizing antibody responses more effectively than soluble trimers. HIV-1 vaccine design through minimizing envelope metastability.,He L, Kumar S, Allen JD, Huang D, Lin X, Mann CJ, Saye-Francisco KL, Copps J, Sarkar A, Blizard GS, Ozorowski G, Sok D, Crispin M, Ward AB, Nemazee D, Burton DR, Wilson IA, Zhu J Sci Adv. 2018 Nov 21;4(11):eaau6769. doi: 10.1126/sciadv.aau6769. eCollection, 2018 Nov. PMID:30474059[1] From MEDLINE®/PubMed®, a database of the U.S. National Library of Medicine. See AlsoReferences
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