Cell therapy for Parkinson's disease with induced pluripotent stem cells

Parkinson’s disease (PD) is the second most common neurodegenerative disease and a prime target of cell therapies. In fact, aborted fetal tissue has been used as donor material for such therapies since the 1980s. These cell therapies, however, suffer from several problems, such as a short supply of donor materials, quality instability of the tissues, and ethical restrictions. The advancement of stem cell technologies has enabled the production of donor cells from pluripotent stem cells with unlimited scale, stable quality, and less ethical problems. Several research groups have established protocols to induce dopamine neural progenitors from pluripotent stem cells in a clinically compatible manner and confirmed efficacy and safety in non-clinical studies. Based on the results from these non-clinical studies, several clinical trials of pluripotent stem cell-based therapies for PD have begun. In the context of immune rejection, there are several modes of stem cell-based therapies: autologous transplantation, allogeneic transplantation without human leukocyte antigen-matching, and allogeneic transplantation with matching. In this mini-review, several practical points of stem cell-based therapies for PD are discussed

The Role of Kallikrein-Related Peptidases in Atopic Dermatitis

Excessive protease activity is a characteristic abnormality that affects the epidermal barrier in patients with atopic dermatitis (AD). Kallikrein-related peptidases (KLKs) are excessively expressed in AD lesions, and it is suggested that the abnormal action of KLKs is involved in the skin barrier dysfunction in AD. In other words, overexpressed KLKs disrupt the normal barrier function, and due to that breakdown, external substances that can become antigens of AD easily invade the epidermis, resulting in dermatitis, coupled with the induction of Th2 cytokines. Further investigations are required to elucidate the role of KLKs in AD; this knowledge could contribute to the design of new therapeutic and prophylactic drugs for AD

Glycocalyx Degradation in Retinal and Choroidal Capillary Endothelium in Rats with Diabetes and Hypertension

Endothelial glycocalyx (GCX) has been reported as a protective factor for vascular endothelial cells (VEC) in diabetes and hypertension. However, the involvement of GCX impairment in ocular vasculopathy remains unclear. We evaluated the changes in the GCX thicknesses of the retinal and choroidal capillaries in rats with diabetes and hypertension by cationic colloidal iron staining using a transmission electron microscope. In the control group, the mean (standard error of the mean) thicknesses of retinal and choroidal GCX were 60.2 (1.5) nm and 84.3 (3.1) nm, respectively. The diabetic rats showed a significant decrease of GCX thickness in the retina, but not in the choroid, compared to controls (28.3 (0.3) nm, p＜0.01 and 77.8 (1.4) nm, respectively). In the hypertensive rats, both retinal and choroidal GCX were significantly decreased compared to the control values (10.9 (0.4) nm and 13.2 (1.0) nm, respectively, both p＜0.01). Moreover, we could visualize the adhesion of leukocytes and platelets on the luminal surface of VEC, at the site where the GCX was markedly degraded. These findings suggest that the GCX prevents adhesion of leukocytes and platelets to the VEC surface, and this impairment may lead to ocular vasculopathy in diabetes and hypertension

Surgical Treatment of Epiretinal Membrane

Epiretinal membrane (ERM) is a common retinal disease characterized by cellular proliferation and metaplasia that lead to the formation of a pathological fibrocellular membrane immediately superjacent to the inner retinal surface. The vast majority of ERMs are considered idiopathic. However, ERM formation can result from various primary intraocular diseases, including retinal breaks and detachment, retinal vascular diseases, and vitreoretinal inflammatory conditions. Although ERMs are generally asymptomatic or cause mild metamorphopsia and/or a modest decrease in visual acuity, some can cause severe macular distortion and macular edema, resulting in significantly impaired function. Surgical removal of ERM is the only treatment, and improvements in vitrectomy systems have enabled less invasive treatment. However, there are currently no standardized criteria for ERM surgery, and the indications for surgery are determined from the patient’s subjective symptoms. Another problem with ERM surgery is that not all patients show satisfactory postoperative recovery of visual function. Thus, further research is needed to determine the criteria for ERM surgery and methods to improve the postoperative prognosis

Evading the Immune System: Immune Modulation and Immune Matching in Cell Replacement Therapies for Parkinson’s Disease

Stem cell-based therapies for Parkinson’s disease are now being applied clinically. Notably, studies have shown that controlling the graft-induced immune response improves the results. In this mini-review, we concisely summarize current approaches used for this control. We focus on four modes of stem cell-based therapies: autologous transplantation, allogeneic transplantation with human leukocyte antigen-matching and allogeneic transplantation without, and finally the application of “universal” pluripotent stem cells. We also discuss immuno-suppressive treatments and the monitoring of immune reactions in the brain

Bilateral Blunt Ocular Trauma Caused by an Exercise Resistance Band during Muscle Building Exercise for Swimming

An 18-year-old male high school student presented to our clinic with bilateral blunt ocular trauma caused by an exercise resistance band (ERB) during a muscle-building exercise. Best-corrected decimal visual acuities (BCVAs) for right and left eyes were light perception and 0.15, respectively. The right eye was operated 10 days after injury for persistent vitreous hemorrhage, and the left eye 5 months later because of macular hole onset. After 36 months, the right eye showed extensive retinal degeneration (BCVA 0.04), and the left eye macular hole closure (BCVA 1.2). ERBs should be used cautiously as they can cause serious ocular trauma

Embedding of Epiretinal Proliferation for a Secondary Lamellar Macular Hole 12 Years after Rhegmatogenous Retinal Detachment Repair

A 58-year-old Japanese man underwent vitrectomy for rhegmatogenous retinal detachment (RRD) in 2002. Twelve years later, optical coherence tomography revealed the development of a lamellar macular hole; the visual acuity was 20/200. Two years later, because metamorphopsia and the foveal retina thinning were aggravated, epiretinal proliferation embedding was performed to restore the foveal structure by transplanting glial cells to the foveal cavity. The patient was followed-up for 4 years, and his macular morphology and visual acuity (20/66) improved. No complications occurred. This appears to be the first report of epiretinal proliferation embedding for a lamellar macular hole post-RRD repair

Assessment of epiretinal membrane formation using en face optical coherence tomography after rhegmatogenous retinal detachment repair

Purpose　To investigate epiretinal membrane (ERM) formation using en face optical coherence tomography (OCT) after vitrectomy for rhegmatogenous retinal detachment (RRD). Methods　We retrospectively reviewed the medical records of 64 consecutive eyes (64 patients) with RRD treated by vitrectomy without ERM and internal limiting membrane peeling. ERMs and retinal folds were detected by B-scan and en face imaging. The maximum depth of retinal folds (MDRF) was quantified using en face imaging. ERM severity was staged using B-scan imaging. Main outcome measures were ERM detection rate with B-scan and en face imaging, MDRF, ERM staging, postoperative best-corrected visual acuity (BCVA; logarithm of the minimum angle of resolution), and risk factors for ERM formation. Results　The detection rate for ERM formation was significantly higher with en face imaging (70.3%) than with B-scan imaging (46.9%; P = 0.007). There was no significant difference in postoperative BCVA between eyes with ERM formation (0.06 ± 0.26) and those without ERM formation (0.01 ± 0.14; P = 0.298). Forty of 45 (88.9%) eyes with ERM formation were classified as stage 1. Twenty-seven of 45 (60.0%) eyes with ERM formation developed parafoveal retinal folds. The mean MDRF was 27.4 ± 32.2 μm. Multiple retinal breaks and a maximum retinal break size of ≥ 2 disc diameters were significantly associated with ERM formation (P = 0.033 and P = 0.031, respectively). Conclusion　Although ERM formation was observed in 70.3% patients after RRD repair, the formed ERM was not severe and had minimal impact on the postoperative visual acuity

Development of Atmospheric Monitoring System at Akeno Observatory for the Telescope Array Project

We have developed an atmospheric monitoring system for the Telescope Array experiment at Akeno Observatory. It consists of a Nd:YAG laser with an alt-azimuth shooting system and a small light receiver. This system is installed inside an air conditioned weather-proof dome. All parts, including the dome, laser, shooter, receiver, and optical devices are fully controlled by a personal computer utilizing the Linux operating system. It is now operated as a back-scattering LIDAR System. For the Telescope Array experiment, to estimate energy reliably and to obtain the correct shower development profile, the light transmittance in the atmosphere needs to be calibrated with high accuracy. Based on observational results using this monitoring system, we consider this LIDAR to be a very powerful technique for Telescope Array experiments. The details of this system and its atmospheric monitoring technique will be discussed.Comment: 24 pages, 13 figures(plus 3 gif files), Published in NIM-A Vol.488, August 200