Summary
VEGF-C is a recently characterised endothelial growth factor structurally related
to vascular endothelial growth factor (VEGF). We studied the expression of VEGF-C
and VEGF in the cells of peripheral blood and in the umbilical cord blood CD 34+ cells,
representing haematopoietic progenitor cells. Expression of VEGF-C was detected in
the CD34+ cells. In peripheral blood VEGF-C mRNA was restricted to platelets and T-cells.
In contrast to the expression pattern of VEGF-C, VEGF mRNA was detected in all peripheral
blood cell fractions studied, and also in CD34+ cells. VEGF-C mRNA was also detected
in fresh bone marrow samples of acute leukaemia patients, but the expression did not
show lineage specificity. VEGF-C and VEGF polypeptides were present in platelets and
they were released from activated platelets together with the release of β-thromboglobulin,
suggesting that VEGF-C and VEGF reside in the α-granules of platelets. VEGF-C and
VEGF, released from activated platelets, may have a role in angiogenesis during wound
healing, and possibly also in other pathological conditions, such as atherosclerosis,
tumour growth, and metastasis formation.