Those yellow/brown granules are probably hemosiderin, a type of iron pigment that is abundant in mouse spleens.  I don't think you can do anything to get rid of them, but maybe someone else on this list knows. Kim Merriam, MA, HT(ASCP)Cambridge, MA----- Original Message ----From: Émilie Bélanger Trudelle =0ATo: histonet@lists.utsouthwestern.eduSent: Wednesday, January 31, 2007 11:25:51 AMSubject: [Histonet] F4/80 helpHi, I'm using F4/80 (Serotec) for IHC on frozen mouse spleen. I'm using biotinylatedanti-rat IgG from Vector and Vectastain ABC kit and DAB also from Vector . I=0Ahave try a lot of different protocols and incubation time with F4/80 and ialways obtain yellow granules around my positive cells and on my isotypicnegative control as well. Does any one know what these granules are and how toblock their coloration????Thanks Emilie Bélanger=0AUniversité de Montréal    _______________________________________________Histonet mailing listHistonet@lists.utsouthwestern.edu=0Ahttp://lists.utsouthwestern.edu/mailman/listinfo/histonet ____________________________________________________________________________________8:00? 8:25? 8:40? Find a flick in no time with the Yahoo! Search movie showtime shortcut.http://tools.search.yahoo.com/shortcuts/#news
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