Cookies on this website
We use cookies to ensure that we give you the best experience on our website. If you click 'Continue' we'll assume that you are happy to receive all cookies and you won't see this message again. Click 'Find out more' for information on how to change your cookie settings.

The production, purification and characterisation of recombinant gp140 oligomeric envelope glycoproteins derived from six primary isolates of HIV-1 (covering clades A, B, C, D, F and O) are described. Using a Chinese hamster ovary cell expression system, expression levels of between 0.1 and 1 mg/l cell-conditioned culture media were obtained, and purified to >95% by affinity chromatography. A, B, D, F and O clade gp 140s were found to be multimeric, bind to a panel of defined env-specific monoclonal antibodies and interact with CD4 and CXCR4, demonstrating correct folding. Their immunogenicity was confirmed by the generation of high-titre anti-gp140 antibodies in rabbits. The C clade gp140 was incorrectly folded and poorly antigenic. Despite the presence of an unmodified gp120/41 cleavage site, only the B clade gp140 showed significant processing to gp120 and gp41. Each gp140 has a specific pattern of oligomerisation, and varies in its resistance to reducing agents and salt concentration. The binding of gp140 to soluble and cell-surface CD4 and CXCR4 is related to the degree of oligomerisation. The C1 and C5 regions, CD4 binding domain and the epitope defined by the 2G12 monoclonal antibody were well exposed, but the C-terminal region of the extracellular domain of gp41 appears to be occluded by oligomerisation. These reagents have potential as immunogens for use in vaccine development.

Original publication

DOI

10.1016/j.vaccine.2003.08.042

Type

Journal article

Journal

Vaccine

Publication Date

25/02/2004

Volume

22

Pages

1032 - 1046

Keywords

Animals, Antibodies, Monoclonal, CHO Cells, Cricetinae, Cricetulus, Gene Products, env, HIV Antigens, HIV Envelope Protein gp120, HIV-1, Immune Sera, Immunoblotting, Protein Subunits, Rabbits, Receptors, CXCR4, env Gene Products, Human Immunodeficiency Virus