Immunocytochemistry for identifying vascular smooth muscle cells - (Aug/08/2005 )

I have performed immunocytochemistry on vascular smooth muscle cells.
We used an antibody against alfa-actin and had a positive stain showing the lamelar structure in the cytosol.

But is this specific for VSMC's?

Thank you for your time

i don't have an answer, just joining the club hoping someone else will help. i find alpha-actin quite unspecific, even the producers agree this would cross-react with at least endothelial cells and macrophages. unfortunately all articles on cultured smooth muscle cells seem to use this method to assess purity of culture. i thought it might be a good idea to stain for alpha actin AND some macrophage marker (e.g.CD163)

so I add my own question: how can I be sure how many SMCs and how many macrophages are in my explant murine "SMC" culture?

thank you very much!

adrian

I work on HVSMC, and I use the alpha actin monoclonal antibody form sigma, these antibody is specific of the smooth muscle cells, it recognizes the alpha actin isoform. So it can reacts with normal myoepithelial cells and pericyte, but I'm not sure that you find these cells in your culture (it depend of the tissue origin). If you are using the migration form explan to get your SMC, you can have fibroblast contamination, with actin you can make easily the difference between fibroblast and SMC.
For the macrophage marker I never use it , but I know the MOMA witch is specific of macrophage.

I hope these answer will help you