Highly potent, fully recombinant anti-HIV chemokines: reengineering a low-cost microbicide.
New prevention strategies for use in developing countries are urgently needed to curb the worldwide HIV/AIDS epidemic. The N-terminally modified chemokine PSC-RANTES is a highly potent entry inhibitor against R5-tropic HIV-1 strains, with an inhibitory mechanism involving long-term intracellular sequestration of the HIV coreceptor, CCR5. PSC-RANTES is fully protective when applied topically in a macaque model of vaginal HIV transmission, but it has 2 potential disadvantages related to further development: the requirement for chemical synthesis adds to production costs, and its strong CCR5 agonist activity might induce local inflammation. It would thus be preferable to find a recombinant analogue that retained the high potency of PSC-RANTES but lacked its agonist activity. Using a strategy based on phage display, we set out to discover PSC-RANTES analogs that contain only natural amino acids. We sought molecules that retain the potency and inhibitory mechanism of PSC-RANTES, while trying to reduce CCR5 signaling to as low a level as possible. We identified 3 analogues, all of which exhibit in vitro potency against HIV-1 comparable to that of PSC-RANTES. The first, 6P4-RANTES, resembles PSC-RANTES in that it is a strong agonist that induces prolonged intracellular sequestration of CCR5. The second, 5P12-RANTES, has no detectable G protein-linked signaling activity and does not bring about receptor sequestration. The third, 5P14-RANTES, induces significant levels of CCR5 internalization without detectable G protein-linked signaling activity. These 3 molecules represent promising candidates for further development as topical HIV prevention strategies.
Gaertner
Hubert
H
Department of Structural Biology and Bioinformatics, Faculty of Medicine, University of Geneva, 1 Rue Michel Servet, 1211 Geneva 4, Switzerland.
Cerini
Fabrice
F
Escola
Jean-Michel
JM
Kuenzi
Gabriel
G
Melotti
Astrid
A
Offord
Robin
R
Rossitto-Borlat
Irène
I
Nedellec
Rebecca
R
Salkowitz
Janelle
J
Gorochov
Guy
G
Mosier
Donald
D
Hartley
Oliver
O
D000890:Anti-Infective Agents / Q000191:economics* / Q000494:pharmacology*; D000998:Antiviral Agents / Q000494:pharmacology*; D018946:Chemokine CCL5 / Q000737:chemistry; D018925:Chemokines / Q000494:pharmacology*; D004705:Endocytosis / Q000187:drug effects; D006678:HIV / Q000187:drug effects*; D006367:HeLa Cells; D006801:Humans; D007963:Leukocytes, Mononuclear / Q000187:drug effects / Q000821:virology; D015202:Protein Engineering; D019713:Receptors, CCR5 / Q000378:metabolism; D011991:Receptors, Virus / Q000378:metabolism; D011994:Recombinant Proteins / Q000494:pharmacology*; D015203:Reproducibility of Results; D015398:Signal Transduction / Q000187:drug effects
D000890:Anti-Infective Agents; D000998:Antiviral Agents; D018946:Chemokine CCL5; D018925:Chemokines; D019713:Receptors, CCR5; D011991:Receptors, Virus; D011994:Recombinant Proteins