Difco trypsin solution

vCTB were isolated from first-trimester trophoblast (n = 3 early first trimester, n = 3 late first trimester) and normotensive term placentae (n = 3). Purification took place according to the protocol previously detailed by Bischof et al.^{44 (link)} Briefly, isolation of small placental tissue pieces was followed by enzymatic tissue digestion with a Difco Trypsin solution (BD, Le Pont de Claix, France). Next, cell separation was performed in a Percoll gradient (GE Healthcare, Uppsala, Sweden), and immunopurification of the vCTB was performed using monoclonal mouse anti-human CD45 immobilised antibodies (Dako, Glostrup, Denmark).

vCTB were isolated from term normotensive and preeclamptic placentae and from first-trimester trophoblast. Purification took place according to the protocol described by Bischof et al.^{34 (link)}. Briefly, small pieces of placental tissue were isolated and the tissue was enzymatically digested with a Difco Trypsin solution (BD, Le pont de Claix, France). After separation in a Percoll gradient (GE Healthcare, Uppsala, Sweden), the vCTB were immunopurified using monoclonal mouse anti-human CD45 immobilized antibodies (Dako, Glostrup, Denmark).