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Contribution of Human -Defensin 1, 2, and 3 to the Anti-HIV-1 Activity of CD8 Antiviral Factor
Linqi Zhang,1*Wenjie Yu,1Tian He,1Jian Yu,1Rebecca E. Caffrey,2Enrique A. Dalmasso,2Siyu Fu,2Thang Pham,2Jianfeng Mei,2Jaclyn J. Ho,1Wenyong Zhang,1Peter Lopez,1David D. Ho1*
It has been known since 1986 that CD8 T lymphocytes from
certain HIV-1-infected individuals who are immunologically stablesecrete a soluble factor, termed CAF, that suppresses HIV-1
replication.However, the identity of CAF remained elusive despite an
extensivesearch. By means of a protein-chip technology, we identified
acluster of proteins that were secreted when CD8 T cells from
long-termnonprogressors with HIV-1 infection were stimulated. These
proteinswere identified as -defensin 1, 2, and 3 on the basis of
specificantibody recognition and amino acid sequencing. CAF activity
waseliminated or neutralized by an antibody specific for human
-defensins.Synthetic and purified preparations of -defensins
also inhibitedthe replication of HIV-1 isolates in vitro. Taken
together, ourresults indicate that -defensin 1, 2, and 3 collectively accountfor much of the anti-HIV-1 activity of CAF that
is not attributableto -chemokines.
1 Aaron Diamond AIDS Research Center, The
Rockefeller University, 455 First Avenue, New York, NY 10016, USA.
2 Ciphergen Biosystems, Inc., 6611 Dumbarton Circle,
Fremont, CA 94555, USA.
*
To whom correspondence should be addressed. E-mail:
lzhang{at}adarc.org (L.Z.); dho{at}adarc.org (D.D.H.)
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