Expression of the fms-like tyrosine kinase 4 gene becomes restricted to lymphatic endothelium during development.

A Kaipainen, J Korhonen, T Mustonen… - Proceedings of the …, 1995 - National Acad Sciences
A Kaipainen, J Korhonen, T Mustonen, VW Van Hinsbergh, GH Fang, D Dumont, M Breitman…
Proceedings of the National Academy of Sciences, 1995National Acad Sciences
We have recently cloned the human fms-like tyrosine kinase 4 gene FLT4, whose protein
product is related to two vascular endothelial growth factor receptors FLT1 and KDR/FLK1.
Here the expression of FLT4 has been analyzed by in situ hybridization during mouse
embryogenesis and in adult human tissues. The FLT4 mRNA signals first became
detectable in the angioblasts of head mesenchyme, the cardinal vein, and extraembryonally
in the allantois of 8.5-day postcoitus (pc) embryos. In 12.5-day pc embryos, the FLT4 signal …
We have recently cloned the human fms-like tyrosine kinase 4 gene FLT4, whose protein product is related to two vascular endothelial growth factor receptors FLT1 and KDR/FLK1. Here the expression of FLT4 has been analyzed by in situ hybridization during mouse embryogenesis and in adult human tissues. The FLT4 mRNA signals first became detectable in the angioblasts of head mesenchyme, the cardinal vein, and extraembryonally in the allantois of 8.5-day postcoitus (p.c.) embryos. In 12.5-day p.c. embryos, the FLT4 signal decorated developing venous and presumptive lymphatic endothelia, but arterial endothelia were negative. During later stages of development, FLT4 mRNA became restricted to vascular plexuses devoid of red cells, representing developing lymphatic vessels. Only the lymphatic endothelia and some high endothelial venules expressed FLT4 mRNA in adult human tissues. Increased expression occurred in lymphatic sinuses in metastatic lymph nodes and in lymphangioma. Our results suggest that FLT4 is a marker for lymphatic vessels and some high endothelial venules in human adult tissues. They also support the theory on the venous origin of lymphatic vessels.
National Acad Sciences