PGF and preeclampsia: Formed by alternative splicing of the pre-mRNA encoding VEGF-R1. It can bind circulating VEGF and PlGF as it lacks the cytoplasmic and transmembrane domain, thus preventing their interactions with endogenous receptors. Increased in maternal plasma in preeclampsia (Taylor et al., 2003; Levine et al., 2004,2006; Chaiworapongsa et al., 2005; Steinberg et al., 2009)