Active in vitro reduction of antigen presenting cells in human corneal grafts using different chemokines.
BACKGROUND
For the fate of a graft the antigen presenting cells play an important role. Chemokines can lead to enhanced migration of these cells. We therefore investigated if fresh human corneas bear the chemokine receptor 7 (CCR7) and if its ligands can force the emigration of dendritic cells in an in vitro model.


METHODS
We used human corneas excluded for transplantation and performed migration tests using chemokine ligands 19 (CCL19) and 21 (CCL21) or the complement factor 5a (C5a). Emigrated cells were collected up to 35 days and stained by immunofluorescent double labeling in triple layer technique with Langerin/CD207, DC-SIGN/CD209, CD14, and HLA-DR. In parallel, fresh and cultured human corneas were stained for CCR7.


RESULTS
We found in fresh human corneas, as well as in long-term cultured ones, a low CCR7 expression that nearly diminished after 28 days. In vitro Langerhans cell emigration could be enhanced only by CCL19, whereas dendritic cells were strongly influenced by CCL19, CCL21, and C5a. HLA-DR(+) cells showed numerically the highest in vitro emigration rate. Macrophages/monocytes were not influenced by the used chemokines.


CONCLUSIONS
Although human corneas reduce their antigen presenting cells numbers during long-term culture, this effect could be significantly enhanced by using chemokines.
Department of Ophthalmology, Innsbruck Medical University, Austria.
Ulrike M
UM
Irschick
Wolfgang J
WJ
Mayer
Nicole
N
Kranebitter
Nikolaus
N
Romani
Hartwig P
HP
Huemer
Eveline U
EU
Irschick
D000368:Aged; D000369:Aged, 80 and over; D000938:Antigen-Presenting Cells / Q000166:cytology* / Q000378:metabolism; D002465:Cell Movement / Q000187:drug effects; D054415:Chemokine CCL19 / Q000494:pharmacology; D054421:Chemokine CCL21 / Q000494:pharmacology; D018925:Chemokines / Q000494:pharmacology*; D015936:Complement C5a / Q000494:pharmacology; D003315:Cornea / Q000166:cytology* / Q000378:metabolism; D016039:Corneal Transplantation; D005260:Female; D019084:Fluorescent Antibody Technique, Indirect; D006684:HLA-DR Antigens / Q000378:metabolism; D006801:Humans; D008297:Male; D008875:Middle Aged; D009924:Organ Culture Techniques; D054400:Receptors, CCR7 / Q000378:metabolism*; D012867:Skin / Q000166:cytology
C515370:CCR7 protein, human; D054415:Chemokine CCL19; D054421:Chemokine CCL21; D018925:Chemokines; D006684:HLA-DR Antigens; D054400:Receptors, CCR7; D015936:Complement C5a