A theta-defensin composed exclusively of D-amino acids is active against HIV-1.
The ability of certain theta-defensins, including retrocyclin-1, to protect human cells from infection by HIV-1 marks them as potentially useful molecules. Theta-defensins composed of L-amino acids are likely to be unstable in environments that contain host and microbial proteases. This study compared the properties of two enantiomeric theta-defensins, retrocyclin-1, and RC-112. Although these peptides have identical sequences, RC-112 is composed exclusively of D-amino acids, whereas retrocyclin-1 contains only L-amino acids. We compared the ability of these peptides to protect JC53-BL human cells from infection by 30 primary HIV-1 isolates. JC53-BL cells are modified HeLa cells that express surface CD4, CXCR4, and CCR5. They also contain reporter cassettes that are driven by the HIV-1 LTR, and express beta-galactosidase and luciferase. The HIV-1 isolates varied in co-receptor specificity and included subtypes A, B, C, D, CRF01-AE, and G. RC-112 was several fold more potent than retrocyclin-1 across the entire HIV-1 panel. Although RC-112 bound immobilized gp120 and CD4 with lower affinity than did retrocyclin-1, surface plasmon resonance experiments performed with 1 microg/mL of RC-112 and retrocyclin-1 revealed that both glycoproteins were bound to a similar extent. The superior antiviral performance of RC-112 most likely reflected its resistance to degradation by surface-associated or secreted proteases of the JC53-BL target cells. Theta-defensins composed exclusively of D-amino acids merit consideration as starting points for designing microbicides for topical application to the vagina or rectum.
Owen
S M
SM
Division of AIDS, STD, and TB Laboratory Research National Center for HIV, STD, and TB Prevention, Centers for Disease Control and Prevention, Public Health Services, US Department of Health and Human Services, Atlanta, GA 30333, USA. smo2@cdc.gov
Rudolph
D
D
Wang
W
W
Cole
A M
AM
Sherman
M A
MA
Waring
A J
AJ
Lehrer
R I
RI
Lal
R B
RB
D000596:Amino Acids / Q000737:chemistry; D000818:Animals; D019380:Anti-HIV Agents / Q000494:pharmacology; D023082:Defensins / Q000737:chemistry* / Q000378:metabolism / Q000494:pharmacology*; D015658:HIV Infections / Q000188:drug therapy; D015497:HIV-1 / Q000187:drug effects*; D006801:Humans; D013237:Stereoisomerism
D000596:Amino Acids; D019380:Anti-HIV Agents; D023082:Defensins; C450142:theta-defensin