Trefoil factor family peptide 3 (TFF3) is upregulated under experimental conditions similar to dry eye disease and supports corneal wound healing effects in vitro.
OBJECTIVE
To elucidate the role of trefoil family peptide (TFF) 3 at the ocular surface under conditions similar to dry eye disease (DED) and in tears of patients suffering from DED.


METHODS
Trefoil family peptide 3 levels in tear samples from non-Sjögren's DED patients with moderate dry eye were analyzed by ELISA and compared with tears from healthy volunteers. A human corneal epithelial (HCE) cell line was treated with proinflammatory cytokines IL-1β and TNF-α, hyperosmolar medium, or scratching for up to 24 hours. Trefoil family peptide 3 gene expression and protein biosynthesis were analyzed by RT-PCR, immunofluorescence, and ELISA. Migration and proliferation of HCE cells under recombinant (r) human (h) trefoil factor family peptide 3 (TFF3) stimulation were investigated by scratching and bromodeoxyuridine (BrdU) proliferation assays.


RESULTS
Tears of patients suffering from DED contained significantly higher TFF3 levels than tears from healthy volunteers. Stimulation of HCE cells with proinflammatory cytokines, culture under hyperosmolar conditions, or scratching resulted, with the exception of hyperosmolar conditions, in an increase in TFF3 expression and elevated secretion level of TFF3. Cell proliferation decreased and cell migration increased after 24-hours stimulation with rhTFF3.


CONCLUSIONS
These results suggest that inflammatory factors or ocular surface damage as they occur in DED, lead to an increase of TFF3 tear film concentration, whereas hyperosmolarity does not. Our data underline a potential role for TFF3 as a candidate therapeutic for the ocular surface damage observed in DED.
Department of Anatomy and Cell Biology, Martin Luther University Halle-Wittenberg, Halle (Saale), Germany.
Ute
U
Schulze
Ulrike
U
Hampel
Saadettin
S
Sel
Laura
L
Contreras-Ruiz
Martin
M
Schicht
Julia
J
Dieckow
Yolanda
Y
Diebold
Friedrich
F
Paulsen
D000704:Analysis of Variance; D016022:Case-Control Studies; D002465:Cell Movement / Q000187:drug effects; D049109:Cell Proliferation / Q000187:drug effects; D002478:Cells, Cultured; D016207:Cytokines / Q000494:pharmacology; D015352:Dry Eye Syndromes / Q000378:metabolism*; D004797:Enzyme-Linked Immunosorbent Assay; D004847:Epithelial Cells / Q000187:drug effects / Q000378:metabolism; D019573:Epithelium, Corneal / Q000187:drug effects / Q000502:physiology*; D006801:Humans; D010455:Peptides / Q000032:analysis / Q000378:metabolism* / Q000494:pharmacology; D016133:Polymerase Chain Reaction; D013666:Tears / Q000737:chemistry / Q000378:metabolism*; D000071165:Trefoil Factor-3; D015854:Up-Regulation; D014945:Wound Healing / Q000187:drug effects / Q000502:physiology*
D016207:Cytokines; D010455:Peptides; C082495:TFF3 protein, human; D000071165:Trefoil Factor-3
ITF; TFF3; dry eye syndrome; ocular surface