Objective Analysis of Corneal Nerves and Dendritic Cells. / Objektive Analyse von Hornhautnerven und dendritischen Zellen.

Corneal nerves and dendritic cells are increasingly being visualised to serve as clinical parameters in the diagnosis of ocular surface diseases using intravital confocal microscopy. In this review, different methods of image analysis are presented. The use of deep learning algorithms, which enable automated pattern recognition, is explained in detail using our own developments and compared with other established methods.

Outcomes and complications of cataract surgery in patients with chronic ocular graft-versus-host-disease-a multicenter, retrospective analysis.

PURPOSE: To evaluate the outcome of phacoemulsification in patients with chronic ocular Graft-versus-host disease (oGVHD) after allogeneic hematopoietic stem cell transplantation (aHSCT). METHODS: Retrospective, observational multicenter study from 1507 oGVHD patients. From the patient files, data were collected including best-corrected visual acuity (BCVA), intraocular pressure (IOP), Schirmer's test I, tear film break-up time (TFBUT), corneal fluorescein staining score, postoperative complications, and pre- and post-operative topical therapy. RESULTS: Seventy-three patients underwent cataract surgery in 104 eyes. In n = 84 eyes, the oGVHD NIH grade was documented; 12% (n = 12) of analyzed eyes were staged oGVHD NIH grade 1, 31% (n = 32) NIH 2 and 39% (n = 41) NIH 3. The mean BCVA improved in 82% of the eyes (n = 86 eyes). BCVA significantly increased from 0.7 ± 0.5 to 0.4 ± 0.4 LogMAR after surgery independent from oGVHD severity. The mean IOP decreased from 14 ± 4 to 13 ± 4 mmHg after surgery. Visual acuity was moderately correlated to the pre-operative degree of corneal staining (Pearson p = 0.26, p = 0.002, Cohen's effect size f = 0.29). The visual acuity decreased by 0.078 LogMar units (95% CI = 0.027-0.141) with each increase of corneal staining by one grade (p = 0.05). After surgery, corneal epitheliopathy increased significantly in 42% (n = 44) of the eyes. Postoperative complications included corneal perforation (n = 6, 6%), cystoid macular edema (n = 4, 4%), and endophthalmitis (n = 1, 1%). CONCLUSION: Phacoemulsification in patients with chronic oGVHD significantly improves visual acuity, but is associated with an increased risk of complications in particular corneal epitheliopathy and corneal perforations.

Detection of systemic immunosuppressants in autologous serum eye drops (ASED) in patients with severe chronic ocular graft versus host disease.

PURPOSE: Chronic graft versus host disease is a major consequence after allogeneic stem cell transplantation (allo-SCT) and has great impact on patients' morbidity and mortality. Besides the skin, liver, and intestines, the eyes are most commonly affected, manifesting as severe ocular surface disease. Treatment protocols include topical steroids, cyclosporine, tacrolimus, and ASED. Since these patients often receive systemic immunosuppressant therapy from their oncologists, a topical re-administration of these drugs via ASED with potentially beneficial or harmful effects is possible. The purpose of the study was to determine whether and to which extent systemic immunosuppressants are detectable in ASED. METHODS: A total of 34 samples of ASED from 16 patients with hemato-oncological malignancies after allo-SCT were collected during the manufacturing process and screened for levels of cyclosporine, mycophenolic acid, everolimus, and tacrolimus via liquid chromatography coupled with tandem mass spectrometry (LC-MS/MS). The study followed the tenets of the Declaration of Helsinki and informed consent was obtained from the subjects after explanation of the nature and possible consequences of the study. RESULTS: Cyclosporine was found in 18 ASED samples in concentrations ranging from 6.5-105.0 ng/ml (32.0 ± 22.8 ng/ml, mean ± SD). The concentration range of mycophenolic acid in 19 samples was 0.04-25.0 mg/l (4.0 ± 5.4 mg/l, mean ± SD). Everolimus and tacrolimus concentrations were well below the respective limits of quantification (< 0.6 and < 0.5 ng/ml) of the established LC-MS/MS method in all samples. CONCLUSIONS: Our study suggests that orally administered cyclosporine and mycophenolic acid for the treatment of systemic GvHD, but not everolimus and tacrolimus, are distinctly detectable in ASED in relevant concentrations. It is highly likely that these agents affect topical therapy of ocular GvHD. However, the extent of this effect needs to be evaluated in further studies.

Tolerance and Adherence to Cationic 0.1% Cyclosporine in Ocular Graft-versus-Host Disease.

INTRODUCTION: Anti-inflammatory, topical therapy of severe keratitis in dry eye disease (DED) and ocular graft-versus-host disease (oGvHD) includes steroids, cyclosporine (Cs), and others. In Germany, a commercial product containing 0.1% Cs in a cationic formulation is available since 2015. OBJECTIVE: The aim of this study was to present real-life data using cationic 0.1% Cs in oGvHD patients. METHODS: This was a retrospective study of 26 oGvHD and 41 DED patients with corneal staining of at least Oxford grade III. Parameters analyzed were Ocular Surface Disease Index, corneal staining, intraocular pressure, tear film break-up time, Schirmer, and visual acuity. In addition, it was evaluated how different Cs formulations were tolerated. RESULTS: Corneal staining improved significantly in 1 eye in DED but not in oGvHD. In DED, cationic 0.1% Cs was not tolerated by 32% of the patients, in contrast to 0.05% Cs in castor oil not tolerated by 47% and liposomal 0.05% Cs by 63%. In oGvHD patients, cationic 0.1% Cs was not tolerated by 62%, 0.05% Cs in castor oil by 33%, and liposomal 0.05% Cs by 39% of the patients. CONCLUSIONS: This study demonstrates differences between the tolerance of different Cs formulations depending on the underlying cause of severe keratitis. Cationic 0.1% Cs is considerably less tolerated in oGvHD, and its use should be considered with care.

Development of a Questionnaire for Detecting Changes in Dry Eye Disease-Related Symptoms.

OBJECTIVES: Determining the changes in symptomatology suffered by dry eye disease (DED) patients after an intervention is difficult because there is only one validated questionnaire specifically designed to measure these changes and it is somewhat complex. This work uses a simplified questionnaire to evaluate the changes in DED-related symptoms. METHODS: A new questionnaire based on a global rating of change scale was designed. The Change in Dry Eye Symptoms Questionnaire (CDES-Q) consists of 2 questions: CDES-Q1 asks for the change in symptoms ("better," "same," or "worse") relative to a determined previous time and CDES-Q2 quantifies this change (range: 0 to +100). To evaluate the CDES-Q, a prospective observational study was performed. At baseline (V1; day-0), DED-related symptoms were evaluated using the ocular surface disease index (OSDI). In the post-treatment visit (V2; day-90), OSDI, Symptoms Assessment Questionnaire in Dry Eye (SANDE) II, and CDES-Q were used. Also, clinical evaluations were performed in each visit. RESULTS: Thirty-six patients were included. At V2, OSDI, SANDE II, and CDES-Q showed a significant reduction in symptoms (-7.17±12.73, P=0.0021; -11.29±20.95, P=0.0035; -25.28±42.28, P=0.0011, respectively). Patients who answered "better" in CDES-Q1 showed a significantly lower SANDE II than those who answered "same" or "worse," while SANDE II did not discriminate between these groups. CONCLUSIONS: CDES-Q can be a useful tool for the evaluation of changes in DED-related symptoms. It is simple and better discriminates patients without changes from those who suffered a worsening than SANDE II.

Meibomian Gland Dysfunction in Ocular Graft vs. Host Disease: A Need for Pre-Clinical Models and Deeper Insights

Despite decades of experience with hematopoietic stem cell transplantation, we are still faced with the delicate equipoise of achieving stable ocular health post-transplantation. This is because ocular graft-versus-host disease (oGvHD) following hematopoietic stem cell transplantation frequently occurs (≥50%) among transplant patients. To date, our understanding of the pathophysiology of oGvHD especially the involvement of the meibomian gland is still limited as a result of a lack of suitable preclinical models among other. Herein, the current state of the etiology and, pathophysiology of oGvHD based on existing pre-clinical models are reviewed. The need for additional pre-clinical models and knowledge about the involvement of the meibomian glands in oGvHD are emphasized.

Ocular Graft-versus-Host Disease in a Chemotherapy-Based Minor-Mismatch Mouse Model Features Corneal (Lymph-) Angiogenesis.

Ocular graft-versus-host disease (oGVHD) is a fast progressing, autoimmunological disease following hematopoietic stem cell transplantation, leading to severe inflammation of the eye and destruction of the lacrimal functional unit with consecutive sight-threatening consequences. The therapeutic "window of opportunity" is narrow, and current treatment options are limited and often insufficient. To achieve new insights into the pathogenesis and to develop new therapeutic approaches, clinically relevant models of oGVHD are desirable. In this study, the ocular phenotype was described in a murine, chemotherapy-based, minor-mismatch GVHD model mimicking early-onset chronic oGVHD, with corneal epitheliopathy, inflammation of the lacrimal glands, and blepharitis. Additionally, corneal lymphangiogenesis was observed as part of oGVHD pathogenesis for the first time, thus opening up the investigation of lymphangiogenesis as a potential therapeutic and diagnostic tool.

Semifluorinated Alkane Eye Drops in Chronic Ocular Graft-versus-Host Disease: A Prospective, Multicenter, Noninterventional Study.

PURPOSE: Ocular graft-versus-host disease (oGvHD) following allogeneic hematopoietic stem cell transplantation develops as severe dry eye disease (DED) and is initially treated with lubricants, although no clinical trials are available using artificial tears in oGvHD. This trial was set up to test perfluorohexyloctane (NovaTears®) as nonpreserved layer-forming agent for the treatment of DED in oGvHD. METHODS: 25 patients with severe DED due to oGvHD received 1 drop perfluorohexyloctane 4 times daily during a prospective, multicenter, observational 12-week study on top of established topical therapy. Clinical parameters included Schirmer test, tear film breakup time, corneal staining, meibum secretion and ocular surface disease index. Adverse events, visual acuity and intraocular pressure were key safety parameters. RESULTS: From 25 patients recruited, 23 presented for the second visit. Perfluorohexyloctane treatment did not lead to any changes in clinical or safety parameters but led to fast relief in symptoms in 57% of the patients. One adverse reaction occurred. CONCLUSIONS: This study showed no change in clinical signs in severe DED due to oGvHD, which was not unexpected due to the underlying pathomechanisms. However, the study showed improvement of symptoms in individual patients allowing application of perfluorohexyloctane as an additional symptomatic therapy in oGvHD.

Disease-Specific Expression of Conjunctiva Associated Lymphoid Tissue (CALT) in Mouse Models of Dry Eye Disease and Ocular Allergy.

Conjunctiva-associated tissue (CALT) is assumed to play a crucial role in the immune system of the ocular surface. Its function in several ocular surface diseases (OSD) is still not fully understood. This study investigates the function of CALT in mouse models of dry-eye disease and ocular allergy. Since antigen-presentation is the central similarity in the pathologies, this study focuses on antigen-presentation in CALT Morphology and the expression of CALT, which was investigated in mice after induction of dry-eye, ocular allergy, topical antigen-stimulation, and after local depletion of phagocytic cells. Antigen uptake was investigated after the application of fluorescent ovalbumin (OVA). OSD influences the appearance and morphology of CALT in a disease-dependent manner. Ocular allergy leads to an increase and dry-eye disease to a decrease in number and size of CALT. The development of CALT is dependent on the presence of APCs. Professional APCs are present in CALT, and soluble antigen is transported into the follicle. CALT appearance is disease-specific and indicative of differing functions. Although the specific involvement of CALT in OSD needs further study, the existence of functional APCS and antigen-uptake supports the hypothesis that CALT is an immunological key player at the ocular surface.

Obese Mice with Dyslipidemia Exhibit Meibomian Gland Hypertrophy and Alterations in Meibum Composition and Aqueous Tear Production.

BACKGROUND: Dyslipidemia may be linked to meibomian gland dysfunction (MGD) and altered meibum lipid composition. The purpose was to determine if plasma and meibum cholesteryl esters (CE), triglycerides (TG), ceramides (Cer) and sphingomyelins (SM) change in a mouse model of diet-induced obesity where mice develop dyslipidemia. METHODS: Male C57/BL6 mice (8/group, age = 6 wks) were fed a normal (ND; 15% kcal fat) or an obesogenic high-fat diet (HFD; 42% kcal fat) for 10 wks. Tear production was measured and meibography was performed. Body and epididymal adipose tissue (eAT) weights were determined. Nano-ESI-MS/MS and LC-ESI-MS/MS were used to detect CE, TG, Cer and SM species. Data were analyzed by principal component analysis, Pearson's correlation and unpaired t-tests adjusted for multiple comparisons; significance set at p ≤ 0.05. RESULTS: Compared to ND mice, HFD mice gained more weight and showed heavier eAT and dyslipidemia with higher levels of plasma CE, TG, Cer and SM. HFD mice had hypertrophic meibomian glands, increased levels of lipid species acylated by saturated fatty acids in plasma and meibum and excessive tear production. CONCLUSIONS: The majority of meibum lipid species with saturated fatty acids increased with HFD feeding with evidence of meibomian gland hypertrophy and excessive tearing. The dyslipidemia is associated with altered meibum composition, a key feature of MGD.

[Second Survey on Patient-centred Care of Ocular Graft-versus-Host Disease in Germany]. / Zweite Umfrage zur Versorgungsstruktur der okulären Graft-versus-Host Disease in Deutschland.

BACKGROUND: graft-versus-host disease (GvHD) is a common complication after allogeneic haematopoietic stem cell transplantation (allo-SCT) and causes immunological rejection of host tissues, which can occur both acute or chronically. Approximately 40 - 80% of patients with the diagnosis of chronic GvHD (cGvHD) also develop ocular GvHD. For these patients, immediate and uncomplicated access to interdisciplinary patient-centred care is important. We performed this survey to improve understanding of the structure of patient-centred care in Germany. METHODS: The GvHD working party of the Cornea Section of the German Society of Ophthalmology sent the "Survey of ocular GvHD 2016" to all university and specialised hospitals in Germany. We evaluated the data and compared the information with survey results from 2014, in order to draw conclusions about the structure and process of patient-centred care in ocular GvHD. Besides the questions from 2014 on the numbers of allo-SCT, frequency of examinations, etc. there were additional questions on the prescription of ciclosporin and autologous serum eye drops. The question on frequency examination was further expanded to include examinations of paediatric patients. RESULTS: Of 30 participating hospitals, 22 had already taken part in the first survey. According to the information they provided, approx. 1860 allo-SCTs were performed in the transplantation units of the participating eye hospitals in 2016. This was more than half of the transplantations performed in Germany. Ophthalmologists examined between 2 and 250 Patients per year per centre. Eight clinics provide a specialised outpatient clinic for ocular GvHD. Nearly all the participating clinics prescribe ciclosporin eye drops. About ⅔ provide autologous serum eye drops, seven obtain them from external sources. Overall approx. 125 - 140 children were examined in 2016. CONCLUSIONS: Due to the potential severity of ocular GvHD with immobilisation of the patients and the imminent loss of sight, further improvements in eye care are required. For example, offers such as special consultations, with expertise located close to any transplantation unit are recommended. This requires in particular ophthalmologists to participate in the patient care to enhance quality of life after allo-SCT. In summary, we conclude that the present structures are not sufficient to treat all patients suffering from ocular GvHD in Germany, but the situation has evidently improved.

A Clinical Phase II Study to Assess Efficacy, Safety, and Tolerability of Waterfree Cyclosporine Formulation for Treatment of Dry Eye Disease.

PURPOSE: To compare the efficacy, safety, and tolerability of waterfree cyclosporine formulation (CyclASol) at 2 concentrations (0.1% and 0.05% of cyclosporine [CsA]) to vehicle when applied twice daily for 16 weeks in patients with dry eye disease (DED). An open-label Restasis (Allergan, Irvine, CA) arm was included to allow a direct comparison with an approved therapy. DESIGN: An exploratory phase II, multicenter, randomized, vehicle-controlled clinical trial, double-masked between CyclASol and vehicle with an open-label comparator. PARTICIPANTS: Two hundred and seven eligible patients with a history of dry eye disease were randomized 1:1:1:1 to 1 of 4 treatment arms (CyclASol 0.05%, n = 51; CyclASol 0.1%, n = 51; vehicle, n = 52, and Restasis, n = 53). METHODS: After a 2-week run-in period with twice-daily dosing of Systane Balance (Alcon, Fort Worth, TX), patients were randomized to the respective treatment arm and dosed twice daily for 16 weeks. MAIN OUTCOME MEASURES: The study was set up to explore efficacy on a number of sign and symptom end points including total and subregion corneal fluorescein staining, conjunctival staining, visual analog scale (VAS) for dry eye symptoms VAS severity, and Ocular Surface Disease Index (OSDI) questionnaire. RESULTS: CyclASol showed a consistent reduction in corneal and conjunctival staining compared with both vehicle and Restasis over the 16-week treatment period, with an early onset of effect (at day 14). A mixed-effects model-based approach demonstrated that the CyclASol drug effect was statistically significant over vehicle (total corneal staining P < 0.1, central corneal staining P < 0.001, conjunctival staining P < 0.01). This model-based analysis suggests a significant CyclASol effect for OSDI as symptom parameter (P < 0.01). The numbers of ocular adverse events were low in all treatment groups. CONCLUSIONS: CyclASol showed efficacy, safety, and tolerability at 2 concentrations in moderate-to-severe DED. In a direct head-to-head against open-label Restasis, CyclASol was found to have an earlier onset of action, as early as after 2 weeks of treatment, in relieving the signs of DED, as measured by corneal and conjunctival staining. The central region of the cornea, an important area for visual function in dry eye sufferers, was shown to have the most benefit from treatment. Excellent safety, tolerability, and comfort profile supports this new CsA formulation as having a positive benefit-to-risk ratio.

Dyslipidemia and Meibomian Gland Dysfunction: Utility of Lipidomics and Experimental Prospects with a Diet-Induced Obesity Mouse Model.

Meibomian gland dysfunction (MGD) is the leading cause of dry eye disease and loss of ocular surface homeostasis. Increasingly, several observational clinical studies suggest that dyslipidemia (elevated blood cholesterol, triglyceride or lipoprotein levels) can initiate the development of MGD. However, conclusive evidence is lacking, and an experimental approach using a suitable model is necessary to interrogate the relationship between dyslipidemia and MGD. This systematic review discusses current knowledge on the associations between dyslipidemia and MGD. We briefly introduce a diet-induced obesity model where mice develop dyslipidemia, which can serve as a potential tool for investigating the effects of dyslipidemia on the meibomian gland. Finally, the utility of lipidomics to examine the link between dyslipidemia and MGD is considered.

Assessment of meibomian glands using a custom-made meibographer in dry eye patients in Ghana.

BACKGROUND: Meibomian Gland Dysfunction (MGD) is a leading cause of evaporative Dry Eye Disease (DED). This makes non-invasive meibography an important procedure in the clinical evaluation of DED patients. Our purpose was to conduct a lead-off investigation focused on the practicality of performing meibography in a developing country, with limited access to complex ophthalmic imaging systems, using a custom meibographer, as a step to future comparative studies on meibomian glands and DED in Africa. METHODS: Meibomian glands(MG) in 76 upper eyelids (UL) and 49 lower eyelids (LL) in 1 eye each of 125 patients randomly selected from a patient population presenting with subjective DED symptoms at a clinic were photographed using a custom meibographer. Single frames were captured, and the MG area determined by intensity threshold segmentation and area calculation using Image J software. MG loss (MGL) was quantified by outlining its area and expressing it as a percentage of the total MG per Pult's grading scheme. Dry eye measures included Tear Film Break Up - Time (TUBT), Schirmer's test and Ocular Surface Staining (OSS). Symptoms were evaluated using the SPEED II questionnaire. Correlations between MGL and age, ocular signs and symptoms were analyzed by Pearson's. Differences between comparable groups were analyzed by Mann - Whitney test; p < 0.05 was considered significant. RESULTS: Overall mean MGL was 32.10% ± 25.0% (26.25% ± 22.40% for UL and 40.33% ± 26.70% for LL). MGL correlated significantly with age [r = 0.91, p = 0.001], SPEED scores [r = 0.90, p = 0.001], OSS [r = 0.75, p = 0.001] and TBUT [r = - 0.81, p = 0.001]. MGL scores were significantly higher in the UL than LL [U = 1293.5 p = 0.004]. CONCLUSION: This study for the first time presents data on the status of Meibomian glands in Africa. It furthermore suggests that it is feasible to examine Meibomian glands using a custom meibographer in developing countries with limited access to complex imaging systems. It also demonstrates the benefit and cost-effectiveness of a simple device by the observed significant relations between meibomian gland loss and DED in these patients.

A semifluorinated alkane (F4H5) as novel carrier for cyclosporine A: a promising therapeutic and prophylactic option for topical treatment of dry eye.

PURPOSE: Cyclosporine A (Cs) has been used as effective topical therapy for inflammatory dry eye disease since more than a decade. However, due to its lipophilic character, Cs is formulated as emulsions or oily solutions for topical application. This experimental study aimed to test if the use of semifluorinated alkanes (SFAs) as a preservative-free, well-tolerated non-stinging or burning vehicle maintains or even improves the benefits of Cs in the topical therapy of dry-eye disease. METHODS: Desiccating stress was applied to C57BL/6 mice for 14 consecutive days to induce experimental dry-eye. Cs dissolved in SFA (perfluorobutylpentane = F4H5with 0.5% Ethanol), F4H5 with 0.5% ethanol only, 0.05% Cs (Restasis®), and dexamethasone (Monodex®) were applied three times daily beginning either at day 4 or day 11 of desiccating stress for up to 3 weeks after end of dry-eye induction. RESULTS: In comparison to other groups, Cs/F4H5 demonstrated high efficacy and earlier reduction of corneal staining. In this study, Cs/F4H5 had the ability to maintain conjunctival goblet cell density once applied on day 4. Flow cytometry analysis from cervical lymphnodes demonstrated a significantly lower CD4+ and CD8+ T-cells in the Cs/F4H5 group following 3 weeks of therapy than at baseline, but no difference in regulatory T cells from regional lymphnodes were seen. CONCLUSIONS: Overall, compared to a commercially available Cs formulation (Restasis®) and dexamethasone, Cs/F4H5 was shown to be equally effective but with a significantly faster therapeutic response in reducing signs of dry-eye disease in an experimental mouse model.

[Influence of Aging on Severity and Anti-Inflammatory Treatment of Experimental Dry Eye Disease]. / Einfluss von Alterung auf Schweregrad und antientzündliche Therapie des experimentellen Trockenen Auges.

Purpose Aging is an important factor in dry-eye disease that has not been studied in the context of therapeutic measures. Aging-associated modifications of the ocular immune system implicate that anti-inflammatory therapies may act differently among younger individuals in terms of onset and effect of different substances. The goal of this study was to determine differences in clinical phenotype and topical anti-inflammatory therapy using a desiccating stress mouse model. Methods An experimental dry-eye disease (desiccating stress model) was induced in 12-week and 12-month-old female BALB/c mice. Topical therapy included 0.05% cyclosporine/F4H5 (Novaliq), F4H5, 0.05% cyclosporine (Restasis®, Allergan) and dexamethasone (Monodex®, Thea Pharma) for 3 consecutive weeks. A control group received no therapy whatsoever. Readout parameters included tear secretion, corneal fluorescein staining at 5 timepoints and histological analysis of goblet cell count at the end of the experiments. Results The older mice demonstrated a significantly stronger dry eye phenotype than the younger mice. Following therapy, the older mice responded to topical anti-inflammatory therapy significantly later than the younger individuals. Regarding the different substances used, cyclosporine/F4H5 showed a significantly faster decrease in corneal fluoresceine staining after only 1 week of therapy in comparison to all other groups. This substance was also superior regarding tear secretion and goblet cell count in age matched groups and in comparison to younger mice. Conclusions These experimental data support the implication that aging should be considered as an important factor in daily clinical practice. Furthermore, the differences found between substance classes, such as calcineurin antagonists and steroids, as well as different drug formulations, should be considered in future pre-clinical and clinical trials.

[New Therapeutic Approaches in Inflammatory Diseases of the Eye - Targeting Lymphangiogenesis and Cellular Immunity: Research Unit FOR 2240 Presents Itself]. / Neue Therapieansätze bei entzündlichen Augenerkrankungen durch Modulation von Lymphangiogenese und zellulärer Immunität: Die DFG-Forschergruppe 2240 stellt sich vor.

Background Ophthalmology, principally, is a very successful subdiscipline in medicine. Nonetheless, there are still unmet medical needs which necessitate translational research. Methods The funding instrument of a Research Unit (RU) of the German Research Foundation (DFG) is presented as exemplified by the RU 2240 at the Department of Ophthalmology at the University of Cologne. Results The Research Unit integrates different research groups working on pathologic ocular inflammation, macrophages/microglia and (lymph)angiogenesis to collaborate in a synergistic way. Rotation positions allow young clinicians to rotate into research labs for a defined period of time. A Research Unit is also a powerful strategic tool to strengthen clinical and experimental ophthalmology at individual medical faculties. Conclusions The funding instrument of a Research Unit is highly suitable for fostering translational research in a medical subdiscipline such as ophthalmology, supporting the next generation of (clinician) scientists in ophthalmology and finding new cures for our patients.

Detection of graft detachments immediately following Descemet membrane endothelial keratoplasty (DMEK) comparing time domain and spectral domain OCT.

PURPOSE: Correct early graft attachment is believed to be crucial for final visual outcome after Descemet membrane endothelial keratoplasty (DMEK). Nonetheless, it is not yet known which imaging technique gives superior results for examining early postoperative graft adherence status. We compared imaging data taken with two different OCT devices to examine the development of graft adherence immediately after DMEK and to determine the superior device in terms of visualization of graft adherence. METHODS: Ten consecutive patients (1 man/9 women) were examined three times postoperatively within the first 7 h after DMEK surgery using spectral domain OCT (SD-OCT) and time domain OCT (TD-OCT), as prospective case series and retrospective image data analyses. The parameters analyzed were localization and number, visibility and size of graft detachments. RESULTS: TD-OCT was able to detect a greater number of graft detachments after DMEK; however, SD-OCT provided better resolution of minor detachments. Graft detachments varied in position and degree at different time points immediately after surgery. All patients had some graft detachment within the first 7 h after DMEK surgery. CONCLUSIONS: TD-OCT enabled better overall analysis of graft detachments, even in the periphery, whereas SD-OCT allowed for the detection of even minor detachments, which suggests that a combination of the two techniques is optimal. Our results indicate that dynamic processes affecting the DMEK graft immediately after transplantation are responsible for changes in the attachment of donor tissue at an early postoperative stage. Modulation of early graft attachment may improve the final graft attachment.

Activated CD4+ T cells enter the splenic T-cell zone and induce autoantibody-producing germinal centers through bystander activation.

CD4(+) T (helper) cells migrate in huge numbers through lymphoid organs. However, little is known about traffic routes and kinetics of CD4(+) T-cell subsets within different organ compartments. Such information is important because there are indications that CD4(+) T cells may influence the function of microenvironments depending on their developmental stage. Therefore, we investigated the migration of resting (naïve), activated, and recently activated (memory) CD4(+) T cells through the different compartments of the spleen. Resting and recently activated CD4(+) T cells were separated from thoracic duct lymph and activated CD4(+) T cells were generated in vitro by cross-linking the T-cell receptor and CD28. The present study shows that all three CD4(+) T-cell subsets selectively accumulate in the T-cell zone of the spleen. However, only activated T cells induce the formation of germinal centers (GCs) and autoantibodies in rats and mice. Our results suggest that in a two-step process they first activate B cells independent of the T-cell receptor repertoire and CD40 ligand (CD154) expression. The activated B cells then form GCs whereby CD154-dependent T-cell help is needed. Thus, activated T cells may contribute to the development of autoimmune diseases by activating autoreactive B cells in an Ag-independent manner.