Kazuhiko Umazume

Profile of intraocular immune mediators in patients with age-related macular degeneration and the effect of intravitreal bevacizumab injection.

Purpose: To measure intraocular cytokine levels in patients with exudative age-related macular degeneration and analyze changes in the cytokine profile 2 days after intravitreal bevacizumab injection. Methods: This prospective case–control study enrolled 37 patients (37 eyes) with age-related macular degeneration including polypoidal choroidal vasculopathy. Twenty-eight age-matched patients (28 eyes) who underwent cataract surgery were used as controls. Undiluted aqueous humor samples were collected after intravitreal bevacizumab injection. Two days after intravitreal bevacizumab injection, cataract surgery was performed and undiluted aqueous humor samples were collected at the beginning of surgery (10 eyes). Twenty-three cytokines were measured using flow cytometry. P values were corrected in multiple comparisons using the conservative Bonferroni–Holm method. The level of significance was set at 0.0022 (0.05/23). Results: At baseline, aqueous humor levels of vascular endothelial growth factor, angiogenin, interferon gamma-inducible protein (IP)-10, macrophage inflammatory protein (MIP)-1&bgr;, monokine induced by interferon &ggr; (Mig), and monocyte chemotactic protein (MCP)-1 were significantly higher in the age-related macular degeneration group than in the control group (P < 0.0022). The result of exploratory multivariate analysis showed that elevated angiogenin level was an important factor that discriminates the two groups (P = 0.0004). Two days after intravitreal bevacizumab injection, vascular endothelial growth factor levels tended to be reduced (P = 0.049), whereas interleukin (IL)-6 and IL-8 levels increased significantly (P < 0.0022). Conclusion: Vascular endothelial growth factor and also angiogenin, IP-10, MCP-1, MIP-1&bgr;, and Mig may be related to the pathogenesis of age-related macular degeneration. Intravitreal bevacizumab injection increases inflammatory cytokine levels, suggesting the induction of an inflammatory process.

Efficacy Of The Inverted Internal Limiting Membrane Flap Technique With Vitrectomy For Retinal Detachment Associated With Myopic Macular Holes

Purpose: To evaluate the anatomical and functional outcome of the inverted internal limiting membrane (ILM) flap technique with vitrectomy for retinal detachment associated with macular hole (MHRD) in highly myopic eyes. Methods: In this retrospective observational study, 21 eyes with MHRD that underwent vitrectomy with conventional ILM peeling (ILM-peeling group, n = 11) or the inverted ILM flap technique (ILM flap group, n = 10) combined with C3F8 tamponade were enrolled in this study. The initial retinal reattachment rate, macular hole closure rate, and postoperative visual acuity at the final visit were compared between the ILM-peeling group and ILM flap group. Results: There was no significant difference in the retinal reattachment rate between ILM-peeling and ILM flap groups (91% and 100%, respectively). The macular hole closure rate in the ILM flap group was 80% (8 of 10 eyes), and was significantly higher than 36% (4 of 11 eyes) in the ILM-peeling group (P = 0.039). Among 12 eyes that achieved macular hole closure, there was no significant difference in median visual acuity after vitrectomy between the ILM flap group and ILM-peeling group (logMAR unit [Snellen acuity]: 1.0 [20/200] and 0.76 [20/125], respectively, P = 0.300). Conclusion: Compared with conventional ILM peeling, the inverted ILM flap technique was more effective for macular hole closure after vitrectomy for MHRD in myopic eye but showed no advantage in the postoperative visual outcome in this study.

Axial length as a factor associated with visual outcome after vitrectomy for diabetic macular edema.

PURPOSE To investigate whether axial length predicts visual acuity outcome after vitrectomy for diffuse macular edema secondary to diabetic retinopathy. METHODS Fifty-one eyes of 41 patients with diabetic macular edema (DME) who underwent vitrectomy were reviewed retrospectively. Clinical data, including axial length measured by partial coherence interferometry, postoperative best-corrected visual acuity (BCVA), and postoperative status of integrity of the photoreceptor layer observed by optical coherence tomography, were recorded. The relationship between axial length and postoperative BCVA or visibility of the junction between the inner and outer segment (IS/OS) line at 12 months after surgery were analyzed. Logistic regression analyses were performed to examine predictors related to postoperative BCVA. RESULTS Median BCVA improved significantly (P < 0.0001) after surgery (0.4 logMAR units; range, 0-1.5) compared to baseline (0.69 logMAR units; range, 0.22-1.22). Median axial length was significantly longer (P = 0.017) when postoperative BCVA was below 0.4 logMAR units (23.51 mm; range, 22.30-26.10) compared to over 0.4 logMAR units (23.02 mm; range, 22.10-24.65). A significant negative correlation was observed between postoperative logMAR and axial length (n = 51, rs = -0.35, P = 0.012). Median axial length was significantly longer (P = 0.039) in eyes with visible IS/OS line (23.54 mm; range, 22.39-26.10) than in those without visible IS/OS line (23.02 mm; range, 22.13-24.65) at 12 months after surgery. Multivariate logistic regression analysis showed that short axial length (odds ratio: 0.3, P = 0.009) increased the risk of poor visual outcome after surgery. CONCLUSIONS Longer axial length predicts better postoperative BCVA after vitrectomy for diffuse macular edema secondary to diabetic retinopathy.

Possible Relation between Lack of Posterior Vitreous Detachment and Severe Endogenous Endophthalmitis

Purpose. Endogenous endophthalmitis (EE) is a rare ocular disease caused by bacterial or fungal infection of intraocular spaces by hematogenous spread of pathogens from distant infectious loci in the body. We investigated the clinical characteristics and management of eyes with EE in ten consecutive patients. Methods. Ten patients (10 eyes) with EE treated at Tokyo Medical University Hospital in 2014 were reviewed. We retrospectively studied the causative organisms, systemic complications, pre/postoperative mean best-corrected visual acuity (BCVA), and status of posterior vitreous detachment (PVD). Results. The 10 patients comprised 8 males and 2 females, with mean age of 71.2 years. The causative organisms were bacteria in 6 eyes and fungi in 4 eyes. Systemic complications included septicemia or disseminated intravascular coagulation in 5 patients and diabetes mellitus in 4 patients. Postoperative BCVA was improved by 0.2log⁡MAR or greater in 4 eyes and decreased in 4 eyes. Vitrectomy was performed in all eyes, and 4 required multiple surgeries. During vitrectomy, PVD was absent in 8 eyes, 4 of which showed retinal necrosis. The mean age of patients with no PVD was 71.2 years. Conclusion. Despite an advanced age, PVD was absent in the majority of patients with EE. PVD may be related to the pathogenesis and aggravation of EE.

Dasatinib affects focal adhesion and myosin regulation to inhibit matrix contraction by Müller cells.

Epiretinal membrane (ERM) contraction is associated with a variety of ocular diseases that cause macular dysfunction. Trans-differentiated Müller cells have been identified in ERMs, and have been implicated to be involved in the contractile process. In this study, we tested the effect of dasatinib, an FDA-approved tyrosine kinase inhibitor, on matrix contraction caused by Müller cells, and examined molecular mechanism of action. Type I collagen matrix contraction assays were used to examine the effect of drugs on matrix contraction by trans-differentiated Müller cells. Fluophore-conjugated phalloidin was used for the detection of actin cytoskeleton, and Western-blot analyses were carried out to examine protein expression and phosphorylation status. Dasatinib inhibited collagen matrix contraction by trans-differentiated Müller cells that was associated with decreased cell spreading and reduction of actomyosin stress fibers. Concomitantly, dasatinib-treated Müller cells had reduced phosphorylation of Src family kinase, paxillin, as well as myosin II light chain. Specific inhibitors of Rho/ROCK and myosin II confirmed the critical role played by this pathway in Müller cell contraction. Our data demonstrate that dasatinib significantly reduced matrix contraction by Müller cells via inhibition of focal adhesion, as well as actomyosin contraction.

PERSISTENT OVERPRODUCTION OF INTRAOCULAR VASCULAR ENDOTHELIAL GROWTH FACTOR AS A CAUSE OF LATE VITREOUS HEMORRHAGE AFTER VITRECTOMY FOR PROLIFERATIVE DIABETIC RETINOPATHY.

Purpose: The purpose of this study was to investigate whether vitreous levels of vascular endothelial growth factor (VEGF) predict late vitreous hemorrhage (VH) after vitrectomy for proliferative diabetic retinopathy, and how VEGF level changes in patients with postoperative late VH. Methods: Eighty-five eyes of 68 patients with proliferative diabetic retinopathy who underwent vitrectomy were analyzed retrospectively. Vitreous samples were collected from eyes undergoing primary vitrectomy and from eyes with late VH undergoing second vitrectomy. Vitreous VEGF levels were measured using enzyme-linked immunosorbent assay. The relationship between VEGF level and late VH (>4 weeks) occurring during follow-up as well as clinical findings, and changes in VEGF level in eyes with late VH undergoing second vitrectomy were analyzed. Results: Late VH occurred in 20 (24%) of 85 eyes, and 9 eyes required second vitrectomy. Vitreous levels of VEGF were significantly higher (median: 1,945 pg/mL; P < 0.0001) in eyes with late VH than in those without. Preexisting iris neovascularization (P < 0.0001), hypertension (P = 0.002), and proteinuria (P = 0.040) were also significant risk factors of late VH. Multivariate logistic regression analysis showed that a higher vitreous VEGF level was independently associated with a risk of postoperative late VH in patients with proliferative diabetic retinopathy (odds ratio: 20.8, 95% confidence interval: 2.72–159.47; P = 0.003). Vitreous VEGF level at second vitrectomy in patients with late VH was significantly lower compared with that at primary vitrectomy, but remained elevated (median: 1,610 pg/mL; P = 0.023). Conclusion: In patients with proliferative diabetic retinopathy, high intraocular VEGF level at primary vitrectomy was identified as an independent risk factor of postoperative late VH. Persistent overproduction of intraocular VEGF may be associated with postoperative late VH.

Comprehensive polymerase chain reaction assay for detection of pathogenic DNA in lymphoproliferative disorders of the ocular adnexa.

Infectious agents have been identified as a major cause of specific types of human cancers worldwide. Several microorganisms have been identified as potential aggravators of ocular adnexal neoplasms; however, given the rarity of these neoplasms, large epidemiological studies are difficult to coordinate. This study aimed to conduct an exhaustive search for pathogenic DNA in lymphoproliferative disorders (LPD) of the ocular adnexa in a total of 70 patients who were diagnosed with LPD of the ocular adnexa between 2008 and 2013. Specimens were screened for bacterial, viral, fungal, and parasitic DNA by multiplex polymerase chain reaction (PCR) and quantitative real-time PCR. Among cases of conjunctival mucosa-associated lymphoid tissue lymphoma, human herpes virus (HHV)-6, HHV-7, chlamydia, Epstein-Barr virus (EBV) and bacterial 16S ribosomal DNA were detected. In cases of IgG4-related ocular disease, similar pathogens were detected but in a larger number of patients. Our PCR assays detected DNAs of various infectious agents in tumor specimens, especially HHV6, HHV7, and EBV, with different positive rates in various types of LPD. Chronic inflammatory stimulation or activation of oncogenes from these infectious agents might be involved in the pathogenesis of LPD of the ocular adnexa.

Aqueous immune mediators in malignant uveal melanomas in comparison to benign pigmented intraocular tumors.

BackgroundTo examine the usefulness of measuring immune mediators in aqueous humor samples for differentiating malignant uveal melanoma from benign pigmented intraocular tumors.MethodsThirteen eyes of 13 patients with uveal melanoma were studied, and 13 eyes of 13 patients with benign pigmented intraocular tumors served as controls. Undiluted samples of aqueous humor were collected, and a cytometric bead array was used to determine the aqueous humor concentrations of 35 immune mediators comprising 14 interleukins (IL), interferon-γ, interferon-γ-inducible protein-10, monocyte chemoattractant protein (MCP)-1, macrophage inflammatory protein (MIP)-1α, MIP-1β, regulated on activation normal T cell expressed and secreted, monokine induced by interferon-γ, basic fibroblast growth factor, Fas ligand, granzyme A, granzyme B, eotaxin, interferon-inducible T-cell alpha chemoattractant, fractalkine, granulocyte macrophage colony-stimulating factor, granulocyte colony-stimulating factor, vascular endothelial growth factor, angiogenin, tumor necrosis factor-α, lymphotoxin-α, and CD40L.ResultsAqueous humor levels of angiogenin, IL-8, and MCP-1 were significantly higher in eyes with malignant melanoma than in those with benign tumors (p < 0.05).ConclusionsAngiogenin, IL-8, and MCP-1 levels in aqueous humor may be potential markers for distinguishing malignant uveal melanoma from benign pigmented intraocular tumors, and may be a useful adjunct to histomorphology, diagnostic imaging, and other biomarkers for the diagnosis and appropriate clinical management of malignant uveal melanoma.

Focal adhesion kinase family is involved in matrix contraction by transdifferentiated Müller cells

ABSTRACT Transdifferentiated Müller cells that adopt a fibroblastic/myofibroblastic phenotype have been identified in epiretinal membranes (ERMs) in several ocular disorders, and have been implicated to play a role in the formation and/or the contraction of ERMs. We have previously demonstrated that dasatinib, a dual inhibitor of Src‐family kinases and Abl kinase, can prevent matrix contraction by transdifferentiated Müller cells. In this study, we examined molecules involved in matrix contraction downstream of primary dasatinib targets. Tyrosine phosphorylation of focal adhesion kinase (FAK) family members FAK and PYK2 was significantly reduced by dasatinib, and select inhibitors for these kinases PF431396, which inhibits both FAK and PYK2, and PF573228, which only inhibits FAK and not PYK2, significantly reduced matrix contraction by transdifferentiated Müller cells. Dasatinib and PF431396 significantly reduced phosphorylation of Hic‐5, a protein implicated to play a role in focal adhesions and cell signaling. Our data shows that FAK family members are involved in matrix contraction by transdifferentiated Müller cells, and also implicates that Hic‐5 is situated downstream of the FAK family within the signaling pathway. HighlightsDasatinib, which prevents Muller cell matrix contraction, inhibits FAK/PYK2.Other FAK/PYK2 inhibitors significantly inhibited Muller cell matrix contraction.Phosphorylation of focal adhesion protein Hic‐5 is reduced by FAK/PYK2 inhibition.