Temporal expression of alternatively spliced forms of tissue factor pathway inhibitor in mice.

BACKGROUND: Mouse tissue factor pathway inhibitor (TFPI) is produced in three alternatively spliced isoforms that differ in domain structure and mechanism for cell surface binding. Tissue expression of TFPI isoforms in mice was characterized as an initial step for identification of their physiological functions. METHODS AND RESULTS: Sequence homology demonstrates that TFPIalpha existed over 430 Ma while TFPIbeta and TFPIgamma evolved more recently. In situ hybridization studies of heart and lung did not reveal any cells exclusively expressing a single isoform. Although our previous studies have demonstrated that TFPIalpha mRNA is more prevalent than TFPIbeta or TFPIgamma mRNA in mouse tissues, western blot studies demonstrated that TFPIbeta is the primary protein isoform produced in adult tissues, while TFPIalpha is expressed during embryonic development and in placenta. Consistent with TFPIbeta as the primary isoform produced within adult vascular beds, the TFPI isoform in mouse plasma migrates like TFPIbeta in SDS-PAGE and mice have a much smaller heparin-releasable pool of plasma TFPIalpha than humans. CONCLUSIONS: The data demonstrate that alternatively spliced isoforms of TFPI are temporally expressed in mouse tissues at the level of protein production. TFPIalpha and TFPIbeta are produced in embryonic tissues and in placenta while adult tissues produce almost exclusively TFPIbeta

Temporal expression of alternatively spliced forms of tissue factor pathway inhibitor in mice.

BACKGROUND: Mouse tissue factor pathway inhibitor (TFPI) is produced in three alternatively spliced isoforms that differ in domain structure and mechanism for cell surface binding. Tissue expression of TFPI isoforms in mice was characterized as an initial step for identification of their physiological functions. METHODS AND RESULTS: Sequence homology demonstrates that TFPIalpha existed over 430 Ma while TFPIbeta and TFPIgamma evolved more recently. In situ hybridization studies of heart and lung did not reveal any cells exclusively expressing a single isoform. Although our previous studies have demonstrated that TFPIalpha mRNA is more prevalent than TFPIbeta or TFPIgamma mRNA in mouse tissues, western blot studies demonstrated that TFPIbeta is the primary protein isoform produced in adult tissues, while TFPIalpha is expressed during embryonic development and in placenta. Consistent with TFPIbeta as the primary isoform produced within adult vascular beds, the TFPI isoform in mouse plasma migrates like TFPIbeta in SDS-PAGE and mice have a much smaller heparin-releasable pool of plasma TFPIalpha than humans. CONCLUSIONS: The data demonstrate that alternatively spliced isoforms of TFPI are temporally expressed in mouse tissues at the level of protein production. TFPIalpha and TFPIbeta are produced in embryonic tissues and in placenta while adult tissues produce almost exclusively TFPIbeta

Endothelial progenitor cells restore renal function in chronic experimental renovascular disease

Background—Endothelial progenitor cells (EPC) promote neovascularization and endothelial repair. Renal artery stenosis (RAS) may impair renal function by inducing intra-renal microvascular (MV) injury and remodeling. We investigated whether replenishment with EPC would protect the renal microcirculation in chronic experimental renovascular disease. Methods and results—Single-kidney hemodynamics and function were assessed using multidetector CT in-vivo in pigs with RAS, RAS 4 weeks after intra-renal infusion of autologous EPC, and controls. Renal MV remodeling and angiogenic pathways were investigated ex-vivo using micro- CT, histology, and Western-blotting. EPC increased renal expression of angiogenic factors, stimulated proliferation and maturation of new vessels, and attenuated renal MV remodeling and fibrosis in RAS. Furthermore, EPC normalized the blunted renal MV and filtration function. Conclusions—The current study shows that a single intra-renal infusion of autologous EPC preserved MV architecture and function and decreased MV remodeling in experimental chronic RAS. Likely, restoration of the angiogenic cascade by autologous EPC involved not only generation of new vessels, but also acceleration of their maturation and stabilization. This contributed to preserving the blood supply, hemodynamics, and function of the RAS kidney, supporting EPC as a promising therapeutic intervention for preserving the kidney in renovascular disease

Poly (lactic-co-glycolic acid) as a controlled release delivery device

10.1007/s10856-009-3727-zJournal of Materials Science: Materials in Medicine2081669-167