An Antibody-Recruiting Small Molecule That Targets HIV gp120

Department of Chemistry, Yale University, 225 Prospect Street, P.O. Box 208107, New Haven, Connecticut 06520-8107, USA.
Journal of the American Chemical Society (Impact Factor: 11.44). 11/2009; 131(45):16392-4. DOI: 10.1021/ja9057647
Source: PubMed

ABSTRACT HIV/AIDS is a global pandemic for which new treatment strategies are desperately needed. We have designed a novel small molecule, designated as ARM-H, that has the potential to interfere with HIV survival through two mechanisms: (1) by recruiting antibodies to gp120-expressing virus particles and infected human cells, thus enhancing their uptake and destruction by the human immune system, and (2) by binding the viral glycoprotein gp120, inhibiting its interaction with the human protein CD4 and preventing virus entry. Here we demonstrate that ARM-H is capable of simultaneously binding gp120, a component of the Env surface viral glycoprotein (found on the surface of both HIV and virus-infected cells) and anti-2,4-dinitrophenyl antibodies (already present in the human bloodstream). The ternary complex formed between the antibody, ARM-H, and gp120 is immunologically active and leads to the complement-mediated destruction of Env-expressing cells. Furthermore, ARM-H prevents virus entry into human T-cells and should therefore be capable of inhibiting virus replication through two mutually reinforcing mechanisms (inhibition of virus entry and antibody-mediated killing). These studies demonstrate the viable anti-HIV activity of antibody-recruiting small molecules and have the potential to initiate novel paradigms in HIV treatment.

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