Monoclonal IgM Antiphosphatidylserine Antibody Reacts Against Cytoskeleton-Like Structures in Cultured Human Umbilical Cord Endothelial Cells
Version of Record online: 9 MAY 2013
American Journal of Reproductive Immunology
Volume 33, Issue 1, pages 97–107, January 1995
How to Cite
Lin, L., Shroyer, L., Walter, A., Lyden, T. W., Ng, A. K. and Rote, N. S. (1995), Monoclonal IgM Antiphosphatidylserine Antibody Reacts Against Cytoskeleton-Like Structures in Cultured Human Umbilical Cord Endothelial Cells. American Journal of Reproductive Immunology, 33: 97–107. doi: 10.1111/j.1600-0897.1995.tb01145.x
- Issue online: 9 MAY 2013
- Version of Record online: 9 MAY 2013
- Accepted July 27, 1994
- Antiphospholipid antibody;
- intermediate filament
PROBLEM: It has been proposed that antibodies against phospholipid-dependent antigens (aPLs), induce recurrent pregnancy loss and thrombosis through modulation of endothelial cell function, yet aPLs have not been conclusively shown to bind with endothelial cells.
METHOD: Using indirect immunofluorescence we investigated the anti-endothelial cell reactivity of three monoclonal antibodies that differentiate between the phospholipids cardiolipin (CL) and phosphatidylserine (PS): BA3B5C4 (CL+/PS+); 3SB9b (CL-/PS+); and D11A4 (CL+/PS-). Cultured umbilical cord endothelial cells were prepared without fixation or with cold acetone fixation.
RESULTS: None of the aPLs reacted with endothelial cells prepared without fixation. 3SB9B reacted strongly with cytoskeletal-like components in acetone-fixed cells, whereas BA3B5C4 and D11A4 were unreactive. The cytoskeletal-like binding of 3SB9b was completely blocked by a monoclonal antibody against vimentin, whereas antibodies against tubulin or actin were not inhibitory. Lipid extraction of the cells destroyed the 3SB9b reactive antigen without affecting the reactivity of anti-vimentin.
CONCLUSION: These results suggest that phospholipid-dependent antigenic determinants are not expressed on the surface of resting endothelial cells but that a PS-dependent antigenic determinant is associated with endothelial cell intermediate filaments.