Engineering Stable, Soluble, and Trimeric HIV gp140 by Paired Cys Scanning

描述（由申请人提供）：当提供合适的抗原包膜（Env）结构时，人体免疫系统可以产生HIV无法逃避的保护性抗体。迄今为止鉴定的许多最有效的中和HIV抗体优先结合Env的三聚体结构。因此，概括了Env的原生三聚体结构

DESCRIPTION (provided by applicant): When presented with a suitable antigenic Envelope (Env) structure, the human immune system can produce protective antibodies that HIV is unable to evade. Many of the most potently neutralizing HIV antibodies identified to date preferentially bind the trimeric structure of Env. Thus, recapitulating the native trimeric structure of Env as it exists on the virus and cell surface is a primary objective in developing an immunogen capable of generating broadly protective humoral immunity. The development of a soluble, trimeric Env structure that recapitulates the native, pre-fusion structure of Env has become a major goal for HIV vaccine advancement. However, the inherent instability of the gp120 and gp41subunit complex has posed a major obstacle in designing a soluble Env trimer (gp140) capable of presenting an effective antigenic structure to the immune system. The goal of this project is to engineer a gp140 variant with disulfide bonds that stabilize the trimer to yield conformationally intact, trimeric gp140. To accomplish the Aims of this project, we will engineer and test up to 10,000 gp140 variants that have been systematically mutated to contain paired disulfide bonds designed to covalently stabilize the protein. Each mutant will be individually expressed in human cells to maintain native post-translational processing, and each mutant will be tested for retention of its pre-fusion conformation, antigenic integrity, and trimeric structure. PUBLIC HEALTH RELEVANCE: This project will contribute to human health by identifying improved gp140 immunogens as vaccine candidates. An improved gp140 immunogen that is stable as a pure, covalently associated trimer and that represents the native gp160 structure as it exists on virions and cells in its pre-receptor binding, pre-fusion conformation is likely to elcit a potent and broadly neutralizing antibody response against HIV.