Use of high-resolution confocal imaging of the vaginal epithelial microstructure to detect microbicide toxicity.
OBJECTIVE
High-resolution optical imaging by confocal reflectance microscopy (CRM) was investigated for its ability to delineate the epithelial microstructure of the vaginal tract and detect alterations that may result from the use of vaginal microbicides.


METHODS
The vaginal tracts of Swiss Webster mice treated with medroxyprogesterone acetate were exposed in vivo to a 4% nonoxynol-9 (N-9)-containing gel or saline. The vaginal tract was removed 4 h, 16 h, or 48 h after treatment and imaged by CRM without staining, and biopsy specimens were obtained from the imaged regions and processed for histological analysis.


RESULTS
In control mice, CRM revealed a columnar epithelium and lamina propria with features resembling those observed via histological analysis. CRM revealed an exfoliated epithelium 4 h and 16 h after N-9 treatment, and quantitative measurement of epithelial thickness revealed a mean thickness (+/- standard error of the mean) of approximately ~41.7 +/- 1.7 mum in control specimens, compared with 14.9 +/- 4.5 mum for specimens obtained 4 h after treatment and 24.4 +/- 2.1 mum for specimens obtained 16 h after treatment. Inflammation 4 h after treatment was indicated through detection of inflammatory infiltrates. In samples collected 48 h after treatment, the epithelium was regenerating. The time line of changes in the morphological structure and epithelial thickness detected by CRM closely resembled that of changes revealed by histological analysis.


CONCLUSIONS
This study demonstrates that CRM can delineate the epithelial structure and detect indicators of inflammation after treatment with N-9 and that it may be a useful imaging tool for evaluating the effects of vaginal microbicides.
Center for Biomedical Engineering , The University of Texas Medical Branch, Galveston, TX 77555, USA. grvargas@utmb.edu
Gracie
G
Vargas
Tuya
T
Shilagard
Rebecca
R
Johnston
Brent
B
Bell
Rachael L
RL
Stegall
Kathleen
K
Vincent
Lawrence
L
Stanberry
Massoud
M
Motamedi
Nigel
N
Bourne
D000818:Animals; D000890:Anti-Infective Agents / Q000633:toxicity*; D002455:Cell Division / Q000187:drug effects; D004847:Epithelial Cells / Q000187:drug effects / Q000473:pathology* / Q000648:ultrastructure; D005260:Female; D017258:Medroxyprogesterone Acetate / Q000494:pharmacology; D051379:Mice; D018613:Microscopy, Confocal; D009092:Mucous Membrane / Q000187:drug effects / Q000648:ultrastructure; D017137:Nonoxynol / Q000633:toxicity; D012680:Sensitivity and Specificity; D014621:Vagina / Q000187:drug effects / Q000473:pathology*
D000890:Anti-Infective Agents; D017137:Nonoxynol; D017258:Medroxyprogesterone Acetate