[Histonet] VEGF - question

[Andrea T. Hooper]

It is not unexpected that the endothelial cells should stain negative for VEGF.

VEGF normally acts through a paracrine mechanism, whereby endothelial 
cells express the receptors for VEGF and the surrounding tissue 
(often times tumor cells) are those that secrete VEGF itself. VEGF 
can be present in a soluble form or as an ECM bound form so it is 
likely that VEGF immunostaining would appear "messy" as you might be 
detecting that which is soluble, ECM bound, or even cytoplasmic VEGF 
which hasn't yet been secreted from the cell.

The only thing to consider is that many anti-VEGF antibodies are 
notorious for being non-specific so plan your experiments with 
careful controls.

May I ask the source of your VEGF antibody and if you are staining 
human or mouse?

Sincerely,
Andrea



At 5:57 PM +0200 6/19/05, Gudrun Lang wrote:
>Maybe a stupid question. Are endothel cells always stained positiv with
>vascular endothelial growth factor?
>
>I have got a tissue of a pyogenic granuloma as a positiv control from my
>pathologist. The endothel cells of  the vessels are clear negativ, the
>surrounding area is positiv.
>
>Is this the expected result or is there any mistake?
>
>
>
>Thanks for your help.
>
>Gudrun Lang

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