Vol 3, No 1 (2018)
Original paper
Published online: 2018-07-20

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Reactivity of corneal and conjunctival epithelial cells to lipopolysaccharide (LPS) and/or irradiation with visible light in vitro

Roman Paduch, Anna Matysik-Woźniak, Ryszard Maciejewski, Anselm G. Jünemann, Robert Rejdak
Ophthalmol J 2018;3(1):1-7.


INTRODUCTION. Visible light and inflammation caused by bacterial endotoxins strongly influence direct cell interactions and modulate the expression of selected factors, such as nitric oxide (NO) and cyclooxygenase-2 (COX-2). The aim of the study is to establish whether exposition of corneal or conjunctival epithelial cells to visible light and/ or LPS may change their viability, direct cellular interactions and expression of NO and COX-2.

MATERIALS AND METHODS. In vitro cultured human corneal and conjunctival epithelial cells were used in the study. The following assays were performed: Neutral Red (NR) uptake, nitric oxide (NO) quantification by the Griess method, cytoskeletal F-actin organization by fluorescent staining, and COX-2 expression by immunofluorescence.

RESULTS. LPS reduced the viability of the cells, especially conjunctival epithelial cells. All cell stimulation variants tested (visible light and/or LPS treatment) led to decreased nitric oxide (NO) production both by corneal and conjunctival epithelial cells. No changes in cytoskeletal F-actin filaments were observed after the cells had been treated with light or the endotoxin. LPS slightly increased COX-2 expression, but light had no, or a slightly reducing, effect on the level of this enzyme.

CONCLUSIONS. Visible light and/or bacterial endotoxin (LPS) may, depending on the local microenvironmental conditions, cooperate or interfere with each other’s activity in inducing ocular surface inflammation.

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