[Histonet] how tissue perfusion affects IHC results

[Subratab]

Dear All,
I am staining renal tissue sections for detection of macrophages (ED1
positive cells). I am getting high number (about 10 folds) of positive cells
in perfused tissue sections (perfused with saline followed by methacarn)
than non-perfused tissue.

My question is what happens with perfusion that makes such a great
difference. Is it only the better preservation of tissue structure/antigens
or there is something associated with the procedure of perfusion that brings
more macrophages during the procedure? Can the tissue handling (like
dissection for identification and canulation of vessels), intrarenal
pressure fluctuations or relative ischemia be responsible for migration of
macrophages into the tissue during perfusion procedure? I am looking for
some expert opinion. Please let me know if there is any related articles on
how tissue perfusion affects IHC results.

Subrata Biswas
PhD Student
UNICAMP, SP, Brazil.