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.

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.

Dry eye (DED) is a prevalent disease with immune-mediated inflammation as the principal pathophysiological etiology. Olive pomace, the major by-product of the olive oil industry, is rich in high-value polyphenols. Their anti-inflammatory and immunomodulatory activities were determined on human CD4+ T cells (hTCD4+) and in a DED animal model. The viability of hTCD4+ cells isolated from peripheral blood and activated with phytohemagglutinin-M was evaluated after treatment for 48 h with an olive pomace extract (OPT3, 0.10–0.40 mg/mL) and its major compound, hydroxytyrosol (25–100 μM). Regarding the DED animal model, 100 μM hydroxytyrosol, 0.20 mg/mL OPT3, or vehicle (borate buffer) were topically administered to 14 days-desiccating stress-exposed (constant airflow/scopolamine administration) C57BL/6 mice. Tear volume, corneal fluorescein staining (CFS), CD4+, and CD8+ T cell count in lymph nodes (flow cytometry), and IP-10 and TNF-α gene expression (qRT-PCR) in the cornea, conjunctiva, and lacrimal glands were evaluated. OPT3 (0.2–0.4 mg/mL) and hydroxytyrosol (100 μM) significantly reduced hTCD4+ proliferation. In mice, both treatments reduced lacrimal gland IP-10 gene expression. OPT3 also decreased CFS, and conjunctival IP-10 and corneal TNF-α gene expression. In lymph nodes, hydroxytyrosol reduced CD3+, OPT3, and CD8+ count. Thus, a high-value application as a promising DED protection was proposed for olive pomace.

Hintergrund Alterung ist ein wichtiger, bislang in Bezug auf therapeutische Maßnahmen jedoch nur unzureichend berücksichtigter Faktor beim Trockenen Auge. Altersabhängige Änderungen in der Funktion des Immunsystems lassen uns davon ausgehen, dass antientzündliche Therapiemaßnahmen Schwankungen in Bezug auf Wirkstoff, Wirkeintritt und Wirkstärke nach sich ziehen. Ziel der Studie war es, am Modell des experimentellen Trockenen Auges altersbezogene Unterschiede der antientzündlichen Therapie zu analysieren. Methoden Ein experimentelles Trockenes Auge (sog. Desiccating Stress Model) wurde an 12 Wochen („jung“) und 12 Monate („alt“) alten weiblichen BALB/c-Mäusen induziert. Das Trockene Auge wurde anschließend mit 0,05% Ciclosporin/F4H5 (Novaliq), F4H5 allein, 0,05% Ciclosporin (Restasis^®, Allergan) und Dexamethason (Monodex^®, Thea Pharma) über 3 Wochen behandelt. Eine Kontrollgruppe erhielt keine Therapie. Es wurden Tränensekretion, Fluoresceinanfärbbarkeit der Hornhaut an insgesamt 5 Zeitpunkten sowie die Becherzellzahl der Konjunktiva histologisch am Ende des Versuchs analysiert. Ergebnisse Im Vergleich zu nicht behandelten Tieren zeigen alte Mäuse ein signifikant stärkeres Trockenes Auge als junge Tiere. In der Therapie sprechen alte Tiere signifikant später an als junge Tiere. Im Vergleich der verwendeten Substanzen zeigt Ciclosporin/F4H5 in Bezug auf die Fluoresceinanfärbbarkeit ein schnelleres Ansprechen schon nach 1 Woche Therapie gegenüber den anderen Gruppen. Ebenso war diese Substanz bei der Tränensekretion und der Zahl der Becherzellen den anderen Gruppen und auch gegenüber jungen Tieren überlegen. Schlussfolgerungen Diese experimentellen Daten implizieren, dass Alterung in der klinischen Beurteilung von Patienten mit Trockenem Auge berücksichtigt werden sollten. Weiterhin bestehen experimentelle Unterschiede zwischen Substanzklassen wie Calcineurinantagonisten und Steroiden, aber auch Unterschiede zwischen unterschiedlichen Substanzformulierungen, die in präklinischen und klinischen Studien berücksichtigt werden sollten. 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.