Franz H. Grus

Genome-wide association analyses identify multiple loci associated with central corneal thickness and keratoconus

Central corneal thickness (CCT) is associated with eye conditions including keratoconus and glaucoma. We performed a meta-analysis on >20,000 individuals in European and Asian populations that identified 16 new loci associated with CCT at genome-wide significance (P < 5 × 10−8). We further showed that 2 CCT-associated loci, FOXO1 and FNDC3B, conferred relatively large risks for keratoconus in 2 cohorts with 874 cases and 6,085 controls (rs2721051 near FOXO1 had odds ratio (OR) = 1.62, 95% confidence interval (CI) = 1.4–1.88, P = 2.7 × 10−10, and rs4894535 in FNDC3B had OR = 1.47, 95% CI = 1.29–1.68, P = 4.9 × 10−9). FNDC3B was also associated with primary open-angle glaucoma (P = 5.6 × 10−4; tested in 3 cohorts with 2,979 cases and 7,399 controls). Further analyses implicate the collagen and extracellular matrix pathways in the regulation of CCT.

The Role of Glia, Mitochondria, and the Immune System in Glaucoma

Author(s): Tezel, Gulgun; Fourth ARVO/Pfizer Ophthalmics Research Institute Conference Working Group

Two-dimensional analysis of tear protein patterns of diabetic patients

In diabetic patients, dry eye and other ocular surface diseases occur more often than in healthy subjects. The aim of this study was to analyze the tear protein patterns of patients suffering from diabetes mellitus type II (dia) and to compare them to the patterns of healthy volunteers (ctrl). Tear proteins of nonstimulated tears of 20 patients (ctrl n = 10, dia n = 10) were separated using two‐dimensional electrophoretic techniques. The protein patterns of each group were analyzed by a multivariate analysis of discriminance. Furthermore, for all spots of each gel, a 50×50 variables pH/Mr (molecular weight) array was generated and subsequently analyzed by a multivariate analysis of discriminance. Additionally, an artificial neural network was trained using the matrix data as input and a sensitivity analysis was performed to figure out, which spots were the most important to differentiate between the tear protein patterns. In both groups a complex staining pattern could be obtained. In diabetic patients significantly more spots were detected compared to the control group (P<0.02). The analysis of discriminance found a highly significant difference between dia and ctrl (P<0.00001). Using the matrix data, the analysis of discriminance showed a significant difference between the two groups, too (P<0.0001). The sensitivity analysis by means of the artificial neural network revealed several spots that were more expressed or more frequently present in the diabetic group. Our findings reveal that the composition of tear proteins of diabetic patients is different from that of healthy subjects. The use of the two‐dimensional electrophoretic technique could give more insight into the diabetic‐related changes in the tear film composition.

Proinflammatory cytokine profiling of tears from dry eye patients by means of antibody microarrays.

PURPOSE In the pathogenesis of keratoconjunctivitis sicca, immune processes are thought to play an important role. However, the exact details of the pathomechanisms are still unknown. In this study, the expression patterns of proinflammatory cytokines in the tears of patients with different subtypes of dry eye were analyzed. METHODS One hundred forty-three subjects subdivided into healthy controls (CTRL, n = 38), patients with aqueous-deficient dry eye (DRYaq, n = 35), patients with changes of the lipid layer (DRYlip, n = 36), and patients with a combination of both (DRYaplip, n = 34) were examined. Expression patterns of proteins (e.g., IL-1β, IL-6, ITNF-α, and IFN-γ) were examined using an advanced antibody microarray approach. RESULTS Several highly significant differences in the cytokine levels of dry eye patients compared with healthy controls were detected. Patients with DRYaq or those with DRYaplip showed elevated levels for most of the tested proteins. For example, IL-1β was found to be elevated 2.4-fold in DRYaq patients and 2.75-fold in DRYaqlip patients (both P < 8.00E-6). The detected amounts of protein in DRYlip patients and in healthy controls showed only minimal differences (fold increase/decrease for all proteins >1.2; P > 5.00E-1). CONCLUSIONS The similarity between the profiles of healthy controls and DRYlip patients justifies the assumption that the pathomechanism of this dry eye subtype is based on mechanisms other than inflammation, whereas it seems to be the case for DRYaq patients.

Autoantibodies in patients with glaucoma: a comparison of IgG serum antibodies against retinal, optic nerve, and optic nerve head antigens

PurposeThe aim of this study was to analyze and compare the entire IgG autoantibody patterns against different ocular antigens (retina, optic nerve, and optic nerve head) in sera of glaucoma patients and healthy subjects.MethodsSixty-six patients were included in this study: healthy volunteers without any ocular disorders (CO, n=30), patients with primary open-angle glaucoma (POAG, n=19), and patients with normal-tension glaucoma (NTG, n=17). The sera were tested for antibodies against retinal, optic nerve, and optic nerve head tissues. Immunodetection was performed using 4-chloro-1-naphthol staining. The autoantibody patterns were digitized and subsequently analyzed by multivariate statistical techniques.ResultsAll patients showed a complex repertoire of IgG antibodies against retinal, optic nerve, and optic nerve head antigens. The analysis of discriminance revealed a statistically significant differences between the patterns of all three groups. Our multivariate approach could quantify the differences in immunoreactivities of patient sera against the three antigens. The POAG group had the most significant difference against retinal antigens (P=0.0021) compared with the other antigens. In the NTG group the highest reactivity appeared against optic nerve head (P=0.00053) and optic nerve (P=0.0025).ConclusionsAll groups showed different and complex antibody patterns against the three ocular tissues. These autoantibodies are highly specific for each patient group. The analysis of these patterns could provide further information about possible autoimmune mechanisms in the pathogenesis of glaucoma.

Antibodies to α B-Crystallin, Vimentin, and Heat Shock Protein 70 in Aqueous Humor of Patients with Normal Tension Glaucoma and IgG Antibody Patterns Against Retinal Antigen in Aqueous Humor

Purpose: To show the existence of IgG antibodies against retinal antigens in aqueous humor of normal tension glaucoma patients. Methods: Forty-two patients were included in this study. Aqueous humor was collected from control subjects (CO; n = 21) and patients with normal tension glaucoma (NTG; n = 21). Western blot methods against bovine retinal antigens were used to detect the IgG antibody patterns. The complex antibody repertoires were analyzed by multivariate statistical techniques. Mass spectrometry was used to identify the most important antigens. Results: Very complex IgG antibody patterns against retinal antigens were found in all analyzed aqueous humor samples. Our multivariate approach could quantify differences in immunoreactivities, and including all peaks, the analysis of discriminance revealed a statistical significant difference between the patterns of the NTG and the CO group (p < 0.001). The antigen band at 21 kDa was identified as α B-crystallin, the 57-kDa antigen band as vimentin, and one at 70 kDa as heat shock protein 70. Conclusions: We could demonstrate that complex IgG antibody patterns against retina exist in aqueous humor. The significant differences in the antibody pattern of the glaucoma group compared with the nonglaucoma group in aqueous humor confirm the results of previous studies using sera of glaucoma patients. These differences in antibody patterns might be further evidence for an autoimmune involvement in the pathogenesis of some glaucoma patients.

Late opacification of the foldable hydrophilic acrylic lens SC60B-OUV

OBJECTIVE To investigate the cause of severe central opacification in 41 foldable acrylic intraocular lenses (IOLs) requiring explantation. Another IOL was opacified in the original sealed vial. DESIGN Case series and laboratory analysis. TESTING Light microscopy, high performance liquid chromatography, sodium dodecyl sulfate polyacoylamide gel electrophoresis, spectrometric analysis, and autoclaving. RESULTS Neither fatty acids nor proteins could be identified within the IOLs. Spectrometric analysis yielded absorption peaks in the ultraviolet spectral range. CONCLUSIONS The spectroscopic findings indicate premature aging of the ultraviolet blocking agent. The source of the opacification is a change in the IOL material itself.

Sera of glaucoma patients show autoantibodies against myelin basic protein and complex autoantibody profiles against human optic nerve antigens

BackgroundThe aim of this study was to gain more information about the possible immunological mechanisms in glaucoma. We analyzed the complex autoantibody patterns against human optic nerve antigens in sera of patients with glaucoma and tried to identify important antigens.MethodsSera of 133 patients were included: healthy control subjects (n = 44), primary open-angle glaucoma (n = 44), and normal tension glaucoma patients (n = 45). The sera were tested against Western blots of human optic nerve, and antibody bands were visualized with chloronaphthol. IgG antibody patterns were analyzed by multivariate statistical techniques, and the most significant antigens were identified by mass spectrometry (Maldi-TOFTOF).ResultsAll subjects, even healthy ones, showed different and complex antibody patterns. Glaucoma groups showed specific up- and down-regulations of antibody reactivities compared to the control group. The multivariate analysis of discriminance found significant differences (P < 0.05) in IgG antibody profiles against human optic nerve antigens between both glaucoma groups and healthy subjects. The identified antigens include: myelin basic protein (up-regulated in the POAG group), glial fibrillary acidic protein (down-regulated in the glaucoma groups), and vimentin (down-regulated in the glaucoma groups in comparison to controls).ConclusionsUsing human optic nerve antigen, we were able to demonstrate that complex IgG autoantibody patterns exist in sera of patients with glaucoma. Large correlations between the given and our previous studies using bovine optic nerve antigens could be seen. Furthermore, anti-myelin basic protein antibodies, which can also be detected in patients with multiple sclerosis, were found in sera of glaucoma patients.

Tears as a source of biomarkers for ocular and systemic diseases

The main focus in clinical proteomics is the discovery of new protein or peptide biomarkers which are correlated with a certain disease. Tear proteins have been investigated extensively in the past and distinct relations between the levels of certain tear proteins to different disorders have been demonstrated. In this review we attempt to summarize proteomic technologies for biomarker identification in tears and some disease related biomarkers in tear fluids that were discovered through different proteomic techniques in different conditions like dry eye, Sjogrens syndrome, contact lens wearers, glaucoma, diabetic retinopathy or cancer. Proteomic analysis of tear fluid has proven to be a promising to gain more information about the pathogenesis of diseases and lead to new diagnostic possibilities. Furthermore, biomarkers represent promising targets for drug development and can be used to monitor the disease state or treatment responses, and accordingly improve the standards of patient care.

Autoimmunity and glaucoma.

Elevated intraocular pressure does not explain glaucoma in all patients, but there is information that autoimmune mechanisms may be involved in this disorder. This review attempts to reveal the findings about specific changes in autoantibody profiles in glaucoma patients and their possible role in glaucoma. Considering that these changes in natural autoimmunity can be found consistently among different study populations, it might be a promising new tool for glaucoma detection.