Three-dimensional in vitro culture of endometrial explants mimics the early stages of endometriosis.
OBJECTIVE
To reproduce the earliest phases of endometriosis using a new in vitro model in which cells from a cultured endometrial fragment can proliferate, invade, reconstitute new endometrial-like tissue, and generate blood vessels.


METHODS
Experimental in vitro study.


METHODS
A hospital-based academic research institute.


METHODS
Five normal ovulating women undergoing surgery for various benign gynecological indications.


METHODS
Endometrial samples obtained from the fundus of the uterine cavity were placed in a three-dimensional fibrin matrix culture system.


METHODS
Degree of proliferation of stromal cells and invasion of the fibrin matrix, gland, and stroma formation, vessel sprouting, and immunohistochemical characterization of various cellular components.


RESULTS
During the first week of culture, an endometrial cell outgrowth was observed from the original fragments in 120 of 144 wells (83.3%). Subsequently, cell outgrowths could be quantified in 132 (91.6%), 129 (89.5%), and 127 (88.1%) of the wells after 15, 60, and 90 days, respectively. An invasion of the matrix by the human endometrial cells led to the formation of tubular structures that coalesced into tissue, architecturally resembling endometrium and in which the glands were immunohistochemically positive for cytokeratin. New capillaries, immunohistochemically positive for CD31 and vimentin, sprouted from the endometrial outgrowths at the beginning of the fifth week of culture.


CONCLUSIONS
These data show that cells from endometrial explants can proliferate and invade a fibrin matrix in vitro generating new glands, stroma, and vessels consistent with endometriosis. The three-dimensional fibrin matrix used in the present study provides an opportunity to observe the earliest biological events of endometriosis in a quantifiable way.
Fasciani
Alessandro
A
Department of Obstetrics and Gynecology, Samuel Lunenfeld Research Institute, Mount Sinai Hospital, Toronto, Ontario, Canada.
Bocci
Guido
G
Xu
Jing
J
Bielecki
Ryszard
R
Greenblatt
Ellen
E
Leyland
Nicholas
N
Casper
Robert F
RF
D002455:Cell Division; D046508:Culture Techniques; D004715:Endometriosis / Q000473:pathology*; D004717:Endometrium / Q000098:blood supply / Q000166:cytology* / Q000378:metabolism / Q000473:pathology; D005260:Female; D006652:Histological Techniques; D006801:Humans; D007091:Image Processing, Computer-Assisted; D007150:Immunohistochemistry; D018919:Neovascularization, Physiologic; D019408:Platelet Endothelial Cell Adhesion Molecule-1 / Q000378:metabolism; D013997:Time Factors; D014746:Vimentin / Q000378:metabolism
D019408:Platelet Endothelial Cell Adhesion Molecule-1; D014746:Vimentin