Expression of extracellular matrix proteins fibulin-1 and fibulin-2 by human corneal fibroblasts.
OBJECTIVE
The fibulins are a family of extracellular matrix (ECM) molecules that regulate the organ shape along with other growth factors and stromal cells. We report here the in vitro expression of ECM proteins fibulin-1 and fibulin-2 by human corneal fibroblasts. The ability of fibulin-1 to modulate cell motility was investigated.


METHODS
Fibulin-1 and fibulin-2 mRNA and proteins expression were analyzed in primary and immortalized human corneal fibroblasts (CHN) respectively by gene array, RT-PCR, and immunocytochemistry. The motility and adhesion of the cells transfected with fibulin-1 siRNA were analyzed on tissue culture polystyrene coated with Matrigel or ECM secreted by those fibroblasts.


RESULTS
(1) The microarray analysis shows the expression of fibulin-1, fibulin-2, and their binding partners (i.e., fibronectin, nidogen-1, aggrecan, fibrilin-1, endostatin, and laminin alpha-2 chain). Interestingly, a matrix metalloprotease, ADAMTS-1, for which fibulin-1 acts as a cofactor, was also detected in CHN. (2) The synthesis by CHN of fibulin-1 and 2 mRNA and proteins was confirmed respectively by RT-PCR and immunocytochemistry. (3) Transfection of CHN by fibulin-1 siRNA has no effect on cell adhesion but increases cell migration compared with that of the control cells. This observation suggests an important role of fibulin-1 on cell motility.


CONCLUSIONS
The expression of fibulins and that of their binding partners by human corneal fibroblasts indicate the important role of these proteins in the organization of supramolecular ECM structures of cornea. The variation of their expression and the structural changes of fibulins remain to be determined in corneal pathology.
Ducros
E
E
UMRS 736 INSERM - Université Pierre et Marie Curie (Paris 6), Faculté de Médecine Paris VI, Paris, France.
Berthaut
A
A
Mirshahi
P
P
Lemarchand
S
S
Soria
J
J
Legeais
J M
JM
Mirshahi
M
M
D051722:ADAM Proteins / Q000235:genetics; D000071097:ADAMTS1 Protein; D053674:Aggrecans / Q000235:genetics; D002135:Calcium-Binding Proteins / Q000235:genetics* / Q000378:metabolism; D002448:Cell Adhesion / Q000502:physiology; D002465:Cell Movement / Q000502:physiology; D002478:Cells, Cultured; D003319:Corneal Stroma / Q000166:cytology*; D043169:Endostatins / Q000235:genetics; D016326:Extracellular Matrix Proteins / Q000235:genetics* / Q000378:metabolism; D000071837:Fibrillins; D005347:Fibroblasts / Q000378:metabolism*; D005353:Fibronectins / Q000235:genetics; D019084:Fluorescent Antibody Technique, Indirect; D015870:Gene Expression; D006801:Humans; D007797:Laminin / Q000235:genetics; D008562:Membrane Glycoproteins / Q000235:genetics; D008840:Microfilament Proteins / Q000235:genetics; D020411:Oligonucleotide Array Sequence Analysis; D012333:RNA, Messenger / Q000378:metabolism; D034741:RNA, Small Interfering / Q000235:genetics; D020133:Reverse Transcriptase Polymerase Chain Reaction; D014162:Transfection
C508319:ACAN protein, human; D053674:Aggrecans; D002135:Calcium-Binding Proteins; D043169:Endostatins; D016326:Extracellular Matrix Proteins; D000071837:Fibrillins; D005353:Fibronectins; D007797:Laminin; D008562:Membrane Glycoproteins; D008840:Microfilament Proteins; D012333:RNA, Messenger; D034741:RNA, Small Interfering; C060820:fibulin; C084612:fibulin 2; C102645:laminin alpha 2; C029967:nidogen; D051722:ADAM Proteins; D000071097:ADAMTS1 Protein; C103859:ADAMTS1 protein, human