Abstract
Purpose: :
Epithelial cells from several mucosal sites (including conjunctiva) have been shown to actively participate during inflammatory episodes by producing and secreting cytokines and chemokines. The aim of this study was to determine the pattern of cytokines/chemokine secretion from conjunctival epithelial cells under the effect of Th1 and Th2–type cytokines to further clarify the role of conjunctival epithelium in ocular surface inflammation.
Methods: :
IOBA–NHC (normal human conjunctival) epithelial cells were exposed to Th1– (IFN–γ and TNF–α) or Th2– (IL–4 and IL–13) derived cytokines for 48 h. Time dependency (30 min, 2 h and 24 h) of TNF–α induced cytokine/chemokine secretion was additionally studied. Cytokine/chemokine production was determined in supernatants by a 22–multiplex bead–based assay in a Luminex 100–IS. Additionally, eotaxin–2 and –3 production was analyzed with by ELISA.
Results: :
After 48 h of Th1 stimulation, cells produced high levels of IL–1α, IL–6, IL8, RANTES and IP10; moderate levels of IL–12p40, eotaxin–1, IL–3, IL–7 and MCP1; low levels of GM–CSF, MIP–1α, IL–1ß and IL–15; and non–detectable levels of IL–2, IL–5, IL–10, IL–12 p70, eotaxin–2 and eotaxin–3. In general, TNF–α produced the highest level of cell stimulation, which was shown to be time–dependent. Th2–cytokines induced a low increase of RANTES, MCP–1, IL–3, IL–6, IL–12p40 and IP10 secretion.
Conclusions: :
Under inflammatory–like conditions, cultured conjunctival epithelial cells secreted proinflammatory cytokines/chemokines molecules that may have a role in initiating and/or amplifying ocular surface inflammation. Therapeutic interventions may therefore need to also target epithelial cells.
Keywords: conjunctiva • cytokines/chemokines