Abstract
Purpose: :
Goblet cells produce mucins and are widely distributed in the mucosal keratinocytes. The development of goblet cells and the critical factors that regulate the differentiation of these cells are poorly understood. We tried to identify the critical factor for goblet cell differentiation.
Methods: :
Human conjunctival tissues were digested by collagenase and completely disaggregated single cells were cultured overnight in serum- and feeder cell-free medium containing B27 and epidermal growth factor (EGF) or fibroblast growth factor 2 (FGF2) in non-tissue culture dishes. Marker expressions on the adherent cells were investigated.
Results: :
We isolated progenitors from human conjunctival keratinocytes. Single progenitors from human conjunctival keratinocytes directly gave rise to goblet cells when incubated with FGF2, while they did not proliferate in the medium with B27 only and formed conjunctival keratinocyte colonies in the presence of EGF. Blockade of FGF receptor 1, but not receptor 2 suppressed differentiation to goblet cells from conjunctival keratinocyte progenitors. Cells from some mucosal keratinocytes (squamous cells) also showed differentiation to goblet cells with FGF2-stimulation.
Conclusions: :
Our findings demonstrate that single conjunctival keratinocyte progenitors can give rise to goblet cells after stimulation by FGF2, which seems to be a common inducer of goblet cell differentiation in keratinocyte progenitors of squamous cell family.
Keywords: conjunctiva • differentiation • growth factors/growth factor receptors