Studies on atherogenesis and corneal transplantation using cultured vascular and corneal endothelia

Transplantation of cultured rhesus monkey vascular endothelial cells to allogeneic cornea concomitant with stripping of Descemet's membrane

CONTEXT

In cases of damaged corneal endothelium cells (CECs) of the eye, transplantation of cultured vascular endothelial cells (VECs) may be a viable method to restore transparency.

AIMS

To evaluate the viability of replacing damaged primate CECs with cultured allogeneic VECs.

SUBJECTS AND METHODS

Rhesus monkey VECs (RMVECs) were cultured and proliferating cells were labeled with bromodeoxyuridine (BrdU) in vitro. RMs of the experimental group (n = 6) underwent manual Descemettt membrane stripping with transplantation of RMVECs labeled with BrdU; those in the control group received manual Descemetnt membrane stripping without transplantation. Postoperative evaluations included the transparency and appearance of the corneal graft; distribution and ultrastructural changes of RMVECs on the inner surface of the cornea using scanning and transmission electron microscopy, and immunohistological identification of BrdU.

RESULTS

At 90 days postsurgery, the corneal grafts of the monkeys in the experimental group retained better transparency than those of the controls, without corneal neovascularization or bullous keratopathy. A layer of cells with positive BrdU staining was found on the posterior surface of the treated corneas in the experimental group, while there was no VEC structure in corneal grafts from the monkeys of the control group.

CONCLUSIONS

RMVECs can grow on the posterior surface of the cornea without Descemet's membrane. Cultured and transplanted RMVECs appeared similar in ultrastructure. VECs can provide a barrier to maintain corneal dehydration and transparency to some extent.

Restoration of normal morphology and estrogen responsiveness in cultured vaginal and uterine epithelia transplanted with stroma

We have investigated the capacity of vaginal and uterine epithelia (VE and UE) to reexpress normal morphology and hormone responsiveness following cell culture. VE and UE from adult ovariectomized mice were grown in a collagen gel matrix with serum-free medium for 7-10 days. Proliferation of these cells occurs in the absence of 17 beta-estradiol and is not stimulated by 17 beta-estradiol; the VE usually does not keratinize or stratify in vitro. Cultured VE and UE were recombined with homologous vaginal or uterine stroma (VS and US, respectively) and these recombinants were grown under the renal capsule of female hosts for 4 weeks. The epithelium of the VS + VE recombinants cycled, proliferated and stratified in response to estrogen and mucified normally in response to progesterone. The UE that was grown in vivo with cultured US also showed normal morphology and estrogen responsiveness. These changes in the UE and VE were not simply a result of return to the in vivo environment, as epithelia alone in collagen gels transplanted under the renal capsule did not survive. These results indicate that both VE and UE, which are not estrogen-dependent in vitro, reexpress their estrogen dependency and normal morphology when recombined with homologous stroma and grown in vivo. Thus, the changes these cells show when grown in culture are the result of altered conditions in vitro rather than an irreversible alteration in the cells themselves or the selection of specific subpopulations that are not mitogenically or morphologically responsive to estrogen under any condition.