FIG. 4.
(A) TEM showing lymphocyte adherence to I407 epithelial monolayer (original magnification, ×7,800). Experiments representative of a minimum of five explants for each condition. (B) TEM showing ultrastructure of stratified cervical ectocervical epithelium following exposure to PM-1 T cells infected with HIV-1BaL (original magnification, ×260). The epithelial sheet has been removed from underlying stroma following overnight treatment with dispase. Epithelial tissue was exposed to cell-associated virus for 2 h in the described diffusion chamber and gently washed before processing for TEM. There is no evidence of adherence or penetration of PM-1 T cells into the epithelium (experiment representative of three). (C) TEM showing single endocervical epithelial monolayer following exposure to PBMC infected with HIV-1BaL (original magnification, ×1,200). Epithelial cells contain multiple mucus-containing vesicles and express multiple microvilli on their apical surface. Endogenous mononuclear cells can be seen in the underlying stromal tissue. The epithelial tissue was exposed to PBMC infected with HIV-1BaL for 2 h and processed as described above. There is no evidence of adherence of paracellular migration of donor PBMC (experiment representative of five).