Presence of alpha smooth muscle actin in lens epithelial cells of aphakic rabbit eyes.

AIMS: To determine whether alpha smooth muscle actin (alpha-SMA), a marker for myofibroblastic cells, is present in lens epithelial cells (LECs) in rabbit aphakic eyes. METHODS: Phacoemulsification was performed in rabbit eyes, which were enucleated after surgery. Immunohistochemical methods were used to detect alpha-SMA in LECs. RESULTS: Five days after surgery, the presence of alpha-SMA positive LECs was observed mainly around the adhesive portion of the anterior capsule margin and the posterior capsule. The posterior capsule was wrinkled at the adhesive portion. The alpha-SMA positive LECs were flattened with spindle-shaped cross sections. Seven days after surgery, the alpha-SMA positive LECs covered most of the central posterior capsule. They disappeared 10 days after surgery. On the other hand, the cuboidal LECs in the capsular bag were negative for alpha-SMA. CONCLUSION: The flattened LECs with spindle-shaped cross sections observed 5 days after cataract surgery contained alpha-SMA. Such LECs were distinguished biochemically from the cuboidal LECs, which lacked alpha-SMA.     

Efficacy and safety of the soft-shell technique in cases with a hard lens nucleus

PURPOSE: To evaluate the efficacy and safety of the soft-shell technique in reducing corneal endothelial cell damage during cataract surgery in patients with a hard lens nucleus. SETTING: Miyata Eye Hospital, Miyakonojo, Miyazaki, Japan. METHODS: Sixty eyes of 57 cataract patients with a hard lens nucleus (Emery-Little classification grade 3 or higher) had phacoemulsification using the soft-shell technique with Healon((R)) (sodium hyaluronate 1%) and Viscoat (sodium hyaluronate 3.0%-chondroitin sulfate 4.0%) (soft-shell group) or with Healon alone (control group). The visual acuity, intraocular pressure (IOP), flare intensity in the anterior chamber, central corneal thickness, and corneal endothelial cell density were evaluated postoperatively. RESULTS: There were no significant IOP elevations in either group. The mean central corneal thickness in the control group was 539 microm +/- 26.0 (SD) preoperatively and 578 +/- 52.0 microm 1 day after surgery; the increase was significant (P =.0154). There was no significant change in the central corneal thickness in the soft-shell group. There were no statistically significant differences between the 2 groups in uncorrected visual acuity, best corrected visual acuity, IOP, flare intensity in the anterior chamber, and central corneal thickness throughout the follow-up. The rate of endothelial cell loss 3 months after surgery was 6.4% +/- 9.6% in the soft-shell group and 16.3% +/- 9.8% in the control group (P =.0003). CONCLUSION: The results suggest that the soft-shell technique is safe and effective in protecting corneal endothelial cells during cataract surgery in patients with a hard lens nucleus.     

The promotion of hepatic maturation of human pluripotent stem cells in 3D co-culture using type I collagen and Swiss 3T3 cell sheets

Hepatocyte-like cells differentiated from human embryonic stem cells (hESCs) or human induced pluripotent stem cells (hiPSCs) are known to be a useful cell source for drug screening. We recently developed an efficient hepatic differentiation method from hESCs and hiPSCs by sequential transduction of FOXA2 and HNF1α. It is known that the combination of three-dimensional (3D) culture and co-culture, namely 3D co-culture, can maintain the functions of primary hepatocytes. However, hepatic maturation of hESC- or hiPSC-derived hepatocyte-like cells (hEHs or hiPHs, respectively) by 3D co-culture systems has not been examined. Therefore, we utilized a cell sheet engineering technology to promote hepatic maturation. The gene expression levels of hepatocyte-related markers (such as cytochrome P450 enzymes and conjugating enzymes) and the amount of albumin secretion in the hEHs or hiPHs, which were 3D co-cultured with the Swiss 3T3 cell sheet, were significantly up-regulated in comparison with those in the hEHs or hiPHs cultured in a monolayer. Furthermore, we found that type I collagen synthesized in Swiss 3T3 cells plays an important role in hepatic maturation. The hEHs or hiPHs that were 3D co-cultured with the Swiss 3T3 cell sheet would be powerful tools for medical applications, such as drug screening.