Abstract
Background. Flt-1 is secreted by various cells and elevated concentrations are present in preeclampsia affecting vascular function. Microparticles from these cells may expose Flt-1. We evaluated whether Flt-1 is microparticle-associated in preeclampsia, and established the origin of Flt-1-exposing microparticles. Methods. The concentration of Flt-1 was measured in samples from preeclamptic patients, pregnant and nonpregnant women by enzyme-linked immunosorbent assay. Microparticles were analyzed by flow cytometry. Western blot determined the different forms of Flt-1. Results. Noncell bound Flt-1 was elevated in preeclampsia compared to controls. A fraction (5%) was associated with microparticles in preeclampsia. Flt-1-exposing microparticles were increased in preeclampsia compared to normotensive pregnancy (p = 0.02). Full-length Flt-1, was identified in microparticles of platelet and placental origin. Conclusion. Full-length Flt-1 is associated with platelet and placenta-derived microparticles. Possibly, the presentation of Flt-1 on the membrane of a microparticle might alter its function, particularly if it acts in synergism with other exposed vasoactive molecules.
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Lok, C.A.R., Böing, A.N., Sargent, I.L. et al. Circulating Platelet-derived and Placenta-derived Microparticles Expose Flt-1 in Preeclampsia. Reprod. Sci. 15, 1002–1010 (2008). https://doi.org/10.1177/1933719108324133
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DOI: https://doi.org/10.1177/1933719108324133