Uveitis is a diverse group of diseases, including infectious, autoimmune, autoinflammatory, and malignant diseases, with large variations. Different responses to treatment and prognoses call attention to the importance of human immunology research and the elucidation of diverse disease pathologies. In recent years, advanced technologies such as single cell analysis and next-generation sequencing (NGS) have developed, which enable us to obtain a great extent of information from a limited amount of clinical specimens. They are powerful tools in elucidating the pathogenesis and stratification of inflammatory diseases. In order to clarify the factors involved in the ocular inflammation and treatment responsiveness, and to develop diagnostic techniques and optimal therapeutics, our laboratory is analyzing intraocular fluid and blood specimens of uveitis at the gene expression, protein, and cellular levels using these state-of-the-art technologies.
We are also collaborating with uveitis treatment specialists and research institutions across the country to advance our research.
Simultaneous comprehensive analysis of uveitis specimens using Cytometry Time by Flight (CyTOF)
Infrequent subsets of peripheral blood mononuclear cells
in the Vogt-Koyanagi-Harada
disease with persistent inflammation have been found.
Yamana et al, Mucosal Immunol 2022
Analysis of cytomegalovirus gene polymorphisms in intraocular fluids and peripheral blood using NGS
Distributions of cytomegalovirus gene polymorphisms in intraocular fluids and peripheral blood differs.
Cytomegaloviruses in intraocular fluids possess higher capacity to escape both from innate and adaptive immunity utilizing HLA-E.
Shirane et al, Front Immunol 2022
Uveitis is one of the refractory eye diseases leading cause of severe loss of vision. It is defined as inflammation of the uvea, which has infectious or non-infectious causes. The precise immunologic mechanisms of uveitis with systemic or autoimmune diseases still remain unclear. Our research group has shown that both Th1 and Th17 cells are responsible for the pathogenesis of uveitis using the rodent model of uveitis (Experimental Autoimmune Uveitis: EAU). (Sonoda KH et al. Acta Ophthalmol. 2011). We recently elucidated that mucosal-associated invariant T (MAIT) cells (Yamana S et al. Mucosal Immunol. 2022) are related to the pathogenesis of uveitis. MAIT cells are an innate-like T cell subset that harbors unique invariant TRAV1-TRAJ33+ chains paired with limited T cell receptor (TCR) β chains. An EAU experiment revealed that genetic depletion of MAIT cells exacerbated retinal pathology. An intravitreal administration of an antigenic metabolite of MAIT cells into EAU mice induced retinal MAIT cell expansion, leading to an improvement in retinal pathology. Further research is currently underway to develop novel therapies for uveitis targeting MAIT cells.
Genetic depletion of MAIT cells exacerbated retinal pathology.
Administration of an antigenic metabolite of MAIT cells improved
Yamana et al, Mucosal Immunol 2022
Intraocular proliferative diseases such as diabetic retinopathy (DR), age-related macular degeneration (AMD) and proliferative vitreoretinopathy (PVR) are a leading cause of decreased vision and blindness in Japan. In those diseases, retinal fibro(vascular) membrane formation above and beneath the retina plays a pivotal role in the primary pathology (Figure 1).
In order to identify genes responsible for intraocular proliferation, we first determined the gene expression profiling of human retina, ERMs associated with proliferative diabetic retinopathy (PDR-ERMs), and PVR (PVR-ERMs) (Figure 2). We next determined "highly expressed genes in PDR- and in PVR-ERMs" by comparing the gene expression profiles between PDR-, PVR-ERMs and the retina. Subsequent analyses identified matricellular proteins, including periostin and tenascin C as important molecules whose expressions are enhanced specifically in proliferating ERMs compared to the retina (Ishikawa K et al. IOVS 2015).
We found increased periostin and tenascin C expression in the vitreous of patients with both PDR and PVR. Immunohistochemical analysis showed colocalization of periostin and α-SMA in PDR- and PVR-ERMs (Kobayashi Y et al. Mol Vis 2016; Ishikawa K et al. FASEB J 2014; Yoshida S et al. IOVS 2012). In vitro, both periostin and tenascin C increased proliferation, adhesion, migration and collagen production in RPE cells. Periostin blockade suppressed migration and adhesion induced by transforming growth factor-β2 (TGF-β2) and PVR vitreous. In vivo, periostin and tenascin C inhibition had the inhibitory effect on experimental retinal and choroidal fibrovascular formation, and progression of experimental PVR without affecting the viability of retinal cells (Kobayashi Y et al. Lab Invest 2016; Ishikawa K et al. FASEB J 2014). These results identified periostin and tenascin C as a pivotal molecule for fibro(vascular) formation. Thus, developing the novel antibody and/or innovative could be a potential therapeutic strategy for inhibiting the progression of intraocular proliferative diseases including DR and AMD.
In the pathogenesis of intraocular fibrosis associated with AMD and PVR, epithelial to mesenchymal transition (EMT) of RPE is one of the important steps; that is, RPE that undergo EMT acquire a fibroblast phenotype with increased capacity to proliferate and migrate and with the ability to produce ECM, which facilitate the formation of fibrotic membrane (Ishikawa K et al. Am J Pathol. 2016). Our comprehensive gene expression analyses of surgically resected human fibrous membranes associated with PDR and PVR revealed the significant EMT-related molecules (Ishikawa K et al. IOVS 2015).
We study the underlying mechanisms in EMT of RPE by investigating the expression and functions of those EMT-related molecules in human samples and/or the animal models of both pre- and subretinal fibrosis (rabbit PVR model and mouse laser-induced CNV model) by real-time PCR, ELISA, Western blot and IHC, etc (Figure 3) (Ishikawa K et al. Sci Rep. 2015; Ishikawa K et al. Exp Eye Res. 2016). Moreover, we explore the biological function and the underlying molecular pathways related to EMT in vitro and seek to establish EMT targeting therapy to prevent fibrosis associated with AMD and PVR (Figure 4).
Inherited retinal diseases (IRDs) are currently incurable disorders with which more than 200 causal genes are associated. Our team aims to elucidate the genotype-phenotype relationships in IRDs as well as to clarify the mechanisms of retinal degeneration, thereby delivering new tools and medicine (e.g. gene therapy, nano-particle medicine, and novel compounds) to IRDs patients with a significant unmet needs. One major interest of our lab is the mechanisms of cell death and neuroinflammation in retinitis pigmentosa (RP), a form of IRDs with rod-cone dystrophy. For example, we have recently identified that circulating blood inflammatory monocytes contribute to the progression of RP, and we are now developing nano-particle medicine that attenuates inflammatory monocytes and peripherally engrafted macrophages (Fig. 1).
Based on our basic and clinical studies, we are now conducting Phase 1/2a clinical trial of neuroprotective gene therapy for patients with RP. In this trial, lentiviral vector encoding pigment epithelium-derived factor (PEDF) is injected into the subretinal space for the purpose of delaying the disease progression (Fig. 2). We are also developing gene therapy agents against other IRDs that are frequent in Asian populations.
Ocular tumor is the life-threatening disease. Our department is one of the specialized institutions for the diagnosis and treatment of ocular tumors in Japan. In the Kyushu university hospital, we treat ocular tumors including orbital tumors, lacrimal gland tumors, eyelid tumors, conjunctival tumors, and intraocular tumors. The number of new cases with ocular tumors is about 250 cases per year. As well as the clinical practice, we are conducting basic research.
Recent advantages in genomic analysis expand our understandings of cancer genomes. These studies can provide us with a novel approach for the selection of the treatment drugs, and sub-classifications of the tumors based on molecular level information. Nevertheless, genomic analyses have been performed in a few tumors in the ophthalmologic field. We have started the genomic analysis of the ocular tumors by comprehensive DNA and RNA sequencing using the next-generation sequencer.
We have also launched a new project using the artificial intelligence (AI). Since the majority of the ocular tumors were rare, the diagnosis of ocular tumor is not easy for the family doctors and general ophthalmologists. Now, our department have the computational server which contains graphic processing units (GPU) in order to develop a deep learning system for the precise diagnosis of ocular tumors.
The town of Hisayama is a suburb of Fukuoka city in Japan. The population rate increase of Japan from 1960 to 2010 is similar to that of Hisayama. Age distribution was almost the same across all age categories in both 1960 and 2010, similar to that of all of Japan. Moreover, distribution of the labor population was also similar between Japan nationally and Hisayama. Therefore, we can say that Hisayama’s population is a good sample for Japan as a whole.
The Hisayama Study is an ongoing, long-term cohort study on cardiovascular disease and its risk factors in the town of Hisayama. As a part of the overall study, an epidemiologic study of eye disease among residents of the town has been under way since 1998.The purpose of our group is to clarify the prevalence, incidence and risk factors for common ocular disease, which cause visual impairment and vision loss, in a general Japanese population.
We started a new glaucoma incidence study from 2012-2013 in partnership with Oita and Akita universities. Several systemic and environmental factors related with the incidence of glaucoma are expected to be revealed. Furthermore, focusing on the potential of retinal imaging technology leading to early detection and diagnosis of dementia, we conduct to examine the relationship between the retina and the brain, and confirm its utility in community-dwelling elderly.
It is a dream of an ophthalmologist to regenerate photoreceptor cells damaged by retinal diseases such as retinal detachment and diabetic retinopathy.
In recent years retinal regenerative medicine using iPS cells has attracted much attention, but we aim to develop retinal regeneration therapy by direct reprogramming, i.e. nerve regeneration therapy not dependent on cell transplantation. The strategy of future retinal regeneration therapy that we consider is to perform radical therapy for the causative disease and retinal regeneration therapy at the same time by injection of medicine into the vitreous at the end of surgery.
We have already developed a method to change astrocytes and Müller cells into progenitor cells by stimulation with a cocktail of small molecular compounds under in vitro environment and then induce differentiation into neurons. Now we are conducting comprehensive compound screening to select the combination of cocktails that lead to more efficient differentiation into neuronal cells.
Young researchers interested in our research, please contact us at any time!