Establishing human lacrimal gland cultures from biopsy-sized tissue specimens.

OBJECTIVES: To establish cultures of human lacrimal gland from patient-derived, biopsy-sized, tissue specimens. METHODS: Tissue was obtained after surgical removal from patients without dry eye disease undergoing routine procedures. Samples were subjected to mechanical and enzymatic digestion and resulting cell suspensions were plated onto collagen-coated glass coverslips and grown for up to 21 days. Cultures were analysed by immunocytochemistry and light microscopy, and resultant cellular distributions were compared to those in sections of fixed human lacrimal gland tissue. RESULTS: Dissociation of biopsy-sized pieces of human lacrimal gland and seeding onto coated surfaces allowed development of a mixed population of cells in vitro. Within 7-14 days, cellular aggregation was observed and by 21 days many cells had organised themselves into distinct three-dimensional complexes. Immunohistochemistry revealed a heterogeneous population of cells, including epithelial, myoepithelial, mesenchymal and progenitor cells. Some of the epithelia labelled positively for lysozyme and lactoferrin. CONCLUSIONS: Collection and dissociation of biopsy-sized pieces of human lacrimal gland leads to a cellular preparation that can proliferate in vitro and organise into three-dimensional structures. This is the first report detailing that biopsy-collected specimens of human lacrimal gland can be used to establish cell cultures.

Histochemical Comparison of Human and Rat Lacrimal Glands: Implications for Bio-Engineering Studies.

Purpose: The purpose of this study was to determine whether rodent lacrimal glands (LGs) represent a suitable surrogate for human tissue in bio-engineering research, we undertook a meticulous histological and histochemical comparison of these two tissues. Methods: Histological techniques and immunohistochemistry were used to compare the structure of adult human and rat LG tissues and the expression of key functional tissue elements. Results: Compared with humans, the rat LG is comprised of much more densely packed acini which are devoid of an obvious central lumen. Myoepithelial, fibroblasts, dendritic cells, T cells, and putative progenitor cells are present in both tissues. However, human LG is replete with epithelium expressing cytokeratins 8 and 18, whereas rat LG epithelium does not express cytokeratin 8. Furthermore, human LG expresses aquaporins (AQPs) 1, 3, and 5, whereas rat LG expresses AQPs 1, 4, and 5. Additionally, mast cells were identified in the rat but not the human LGs and large numbers of plasma cells were detected in the human LGs but only limited numbers were present in the rat LGs. Conclusions: The cellular composition of the human and rat LGs is similar, although there is a marked difference in the actual histo-architectural arrangement of the tissue. Further variances in the epithelial cytokeratin profile, in tissue expression of AQPs and in mast cell and plasma cell infiltration, may prove significant. Translational Relevance: The rat LG can serve as a useful surrogate for the human equivalent, but there exist specific tissue differences meaning that caution must be observed when translating results to patients.

Recurrent orbital inflammation associated with VEXAS syndrome.

VEXAS (Vacuoles, E1 enzyme, X-linked, Autoinflammatory, Somatic) syndrome is a newly recognised adult-onset multisystem autoinflammatory disease caused by a somatic mutation in the UBA1 gene in myeloid or erythroid precursor cells. This report describes an atypical presentation of recurrent dacryoadenitis associated with VEXAS syndrome and provides a review of the literature. A 68-year-old male presented with three episodes of unilateral alternating dacryoadenitis followed by bilateral involvement over a 4-year period. Each episode of orbital inflammation was characterised by upper lid swelling, oedema and enlarged lacrimal glands. In addition, he experienced intermittent flares of angioedema-like lesions involving the face and extremities, recurrent jaw aches, rash, progressive pulmonary fibrosis, and myelodysplastic syndrome. His inflammatory symptoms lessened with prednisolone but were refractory to methotrexate. Mycophenolate was subsequently trialled with a reasonable clinical response. Genetic testing established the diagnosis of VEXAS syndrome and tofacitinib, a JAK inhibitor, was commenced with resolution of inflammatory symptoms.

Pseudocystic appearance of an orbital carcinoid metastasis.

Carcinoid tumours are a low-grade neuroendocrine malignancy that infrequently metastisizes to orbital structures. The typical radiological appearance of carcinoid is a solid, well-circumscribed mass that enhances with contrast. We present a case of orbital carcinoid metastasis with pseudocystic radiological appearance and review of the literature.