Evidence that Nectin-3 is the soybean agglutinin binding protein on rat corneal endothelium cell surfaces.

The means by which the lectin soybean agglutinin (SBA) binds to the corneal endothelium cell surface following explantation into organ culture was investigated using Sprague-Dawley rats. SBA binding does not occur in freshly isolated and fixed rat corneal endothelium. However, after 48 h in organ culture, SBA binding occurs in a punctate pattern that clearly outlines all endothelial cells of the tissue monolayer.

Insulin and IGF-2 support rat corneal endothelial cell growth and wound repair in the organ cultured tissue.

The ability of insulin and IGF-2 to support wound repair in the organ-cultured rat corneal endothelium was investigated. Corneas given a circular transcorneal freeze injury, were explanted into organ cultures containing either insulin or IGF-2 and cultured up to72 h. Both factors increased [H]-thymidine incorporation and mitotic levels compared to controls.

Rat corneal endothelial cell migration during wound repair on the basement membrane depends more on the PI-3K pathway than the cdc-42 pathway or actin stress fibers.

Following a central transcorneal circular freeze injury, organ-cultured rat corneal endothelial cells surrounding the wound reorganize peripheral actin bands into stress fibers and migrate individually into the wound. To ascertain the significance of this rearrangement relative to morphological changes accompanying migration and wound repair, some tissues were incubated overnight in 4 μM TRITC-conjugated phalloidin to stabilize actin and prevent its reorganization. After a freeze injury to the endothelium tissues were histologically observed at 24 h post-wounding and demonstrated that despite a lack of actin organization, cells responding to the injury appeared morphologically similar to their control counterparts.

Fibronectin antibody labels corneal stromal collagen fibrils in situ along their length and circumference and demonstrates distinct staining along the cell and stromal interfaces of Descemet's membrane.

Purpose/aim Of The Study: An immunoperoxidase cytochemical study of fibronectin localization in the rat corneal stroma and Descemet's membrane was conducted following organ culture to determine whether stromal swelling allowed better primary antibody penetration into the normally tough fibrous corneal stroma.

Materials And Methods: Following 24 h organ culture, corneas were fixed in 4% paraformaldehyde, washed and stained overnight at 4 °C in anti-fibronectin followed by washing and incubation in an appropriate secondary antibody and exposure to protein A-HRP. Cytochemical processing was carried out in a DAB-containing medium followed by dehydration and Epon embedding.

The effects of soybean agglutinin binding on the corneal endothelium and the re-establishment of an intact monolayer following injury--a short review.

This short review summarizes the localization and effects of the plant lectin soybean agglutinin (SBA) on the injured and non-injured organ-cultured rat corneal endothelium. Although the tissue exists as a non-cycling monolayer on the posterior corneal surface a circular freeze injury promotes wound repair as cells initiate DNA synthesis, mitosis and migration. As a result, by 24 h post-injury, endothelial cells express a surface protein that binds SBA in a diffuse punctate pattern, which by 48 h after injury, becomes confined to the cell periphery.

Soybean agglutinin binding to corneal endothelial cell surfaces disrupts in situ monolayer integrity and actin organization and interferes with wound repair.

Rat corneal endothelium demonstrates cell-surface soybean agglutinin (SBA) binding during organ-culture or injury. When organ-cultured in medium containing SBA, the endothelial monolayer is disrupted because of cell-cell and cell-matrix alterations. SBA binding disorganizes the circumferential microfilament bundles (CMBs), an effect that is partially prevented by phallacidin preincubation.

5-Fluorouracil interferes with actin organization, stress fiber formation and cell migration in corneal endothelial cells during wound repair along the natural basement membrane.

Corneal endothelial cells respond to a circular freeze wound by undergoing actin cytoskeletal reorganization that is mainly characterized by the disappearance of circumferential microfilament bundles (CMBs) and the subsequent appearance of distinct stress fibers. This cytoskeletal rearrangement is associated with changes in cell shape as migrating cells lose their polyhedral appearance, spread out, and assume a stellate morphology with cell processes extending outward into the injured area. We report here that in the presence of low concentrations (0.

Microfilament disruption in a noncycling organized tissue, the corneal endothelium, initiates mitosis.

The adult corneal endothelium represents a noncycling cell population that resides as a monolayer on its basement membrane, Descemet's membrane. Evidence is presented for the first time, showing that mitotic regulation in this organized tissue, residing on its natural basement membrane, is coupled to microfilament integrity. When mitotically quiescent rat corneal endothelia are organ cultured in medium containing serum and cytochalasin B, low levels of mitosis are initiated.