Abstract:
:We have developed human cervicovaginal organ culture systems to examine the initiating events in HIV transmission after exposure to various sources of HIV infectivity, including semen. Newly infected cells were detected in the cervical submucosa 3-4 days after exposure to a primary HIV isolate. At earlier times, extensive and stable binding occurred when cervical surfaces were exposed to virions or seminal cells. Cervical mucus provided some protection for the endocervical surface, by physically trapping virions and seminal cells. Confocal microscopy combined with 3D surface reconstruction revealed that virions could both bind to the external surface of the cervical epithelium and actually penetrate beneath the epithelial surface. In quantitative assays, pretreatment with a blocking antibody directed against beta1 integrin reduced HIV virion binding. Collectively, these results highlight a continuum of complex interactions that occurs when natural sources of HIV infectivity are deposited onto mucosal surfaces in the female reproductive tract.
journal_name
Proc Natl Acad Sci U S Aauthors
Maher D,Wu X,Schacker T,Horbul J,Southern Pdoi
10.1073/pnas.0500848102keywords:
subject
Has Abstractpub_date
2005-08-09 00:00:00pages
11504-9issue
32eissn
0027-8424issn
1091-6490pii
0500848102journal_volume
102pub_type
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