Homogeneity of mesothelial cells with lymphatic endothelium: expression of lymphatic endothelial markers by mesothelial cells.
BACKGROUND
Mesothelial cell monolayers cover the serous cavities and internal organs, and provide a protective low-friction interface between apposed organs and tissues. The mesothelium also regulates inflammation, fluid and cell exchange, and tissue repair in these compartments and possibly tumor metastasis. In the present study, a stable pleural mesothelial cell line (MIM) was isolated and characterized, and the expression of several lymphatic specific markers by these cells examined.


RESULTS
MIM were isolated from mice stably expressing a temperature-sensitive SV40 large T antigen ('Immortomouse', strain: H-2K(b)-tsA58). These cells were compared with lymphatic endothelial cells (LEC) derived from the mesenteric adventitia of the Immortomouse. MIM and LEC expression of lymphatic-specific markers (Flt-4, LYVE-1, and Prox-1) was examined, and the tight junction protein (ZO-1) was studied by immunofluorescence and immunoblotting in these cells.


RESULTS
LYVE-1, Prox-1, and Flt-4 were detected in both MIM and LEC, with Prox-1 and LYVE-1 more strongly expressed on LEC than MIM. Conversely, Flt-4 was more densely expressed on MIM than on LEC. Spatially, ZO-1 was prominent at MIM junctions, but was less well organized in LEC.


CONCLUSIONS
MIM and LEC share several characteristic markers usually associated with lymphatic endothelium. MIM might be useful for studying the biology and pathology of mesothelial cells in vitro and help in the development of therapies for mesothelial-related diseases, such as mesothelioma and pleural effusion.
Ando
T
T
Department of Molecular and Cellular Physiology, Louisiana State University Health Sciences Center, Shreveport, Louisiana 71130-3932, USA.
Jordan
P
P
Wang
Y
Y
Jennings
M H
MH
Harper
M H
MH
Houghton
J
J
Elrod
J
J
Alexander
J S
JS
D000818:Animals; D000952:Antigens, Polyomavirus Transforming / Q000235:genetics / Q000378:metabolism; D015415:Biomarkers / Q000378:metabolism*; D015153:Blotting, Western; D002460:Cell Line / Q000187:drug effects / Q000378:metabolism; D004729:Endothelium, Lymphatic / Q000166:cytology / Q000378:metabolism*; D004848:Epithelium / Q000378:metabolism; D006023:Glycoproteins / Q000235:genetics / Q000378:metabolism; D018398:Homeodomain Proteins / Q000378:metabolism; D015151:Immunoblotting; D008168:Lung / Q000166:cytology / Q000378:metabolism*; D008565:Membrane Proteins / Q000235:genetics / Q000378:metabolism; D026901:Membrane Transport Proteins; D051379:Mice; D008807:Mice, Inbred BALB C; D008810:Mice, Inbred C57BL; D008811:Mice, Inbred DBA; D008856:Microscopy, Fluorescence; D010750:Phosphoproteins / Q000235:genetics / Q000378:metabolism; D025521:Tumor Suppressor Proteins; D040321:Vascular Endothelial Growth Factor Receptor-3 / Q000378:metabolism; D062826:Zonula Occludens-1 Protein; D000098551:Prospero-Related Homeobox 1 Protein
D000952:Antigens, Polyomavirus Transforming; D015415:Biomarkers; D006023:Glycoproteins; D018398:Homeodomain Proteins; D008565:Membrane Proteins; D026901:Membrane Transport Proteins; D010750:Phosphoproteins; D025521:Tumor Suppressor Proteins; D040321:Vascular Endothelial Growth Factor Receptor-3; D062826:Zonula Occludens-1 Protein; D000098551:Prospero-Related Homeobox 1 Protein; C569043:Tjp1 protein, mouse; C492273:LYVE1 protein, mouse