Teri, 
I just tried DAKO's polyclonal CD117 (also called C-kit) in December and had
good results with a 1:100 dilution with citrate buffer pH6 antigen
retrieval. We microwave 1 rack for 5 minutes, add 50 ml of distilled water,
and microwave another 5 minutes. I used gastrointestinal stromal tumor
(GIST) as a control. 
Best of luck, 
Rachel Stock

>Hi out there in histoland!  Is anyone using CD117, polyclonal antibody?  We
>are titering it and have noticed some non-specific staining in muscle. The
>spec sheet says to avoid proteolytic enzymes (so we avoided them).  It also
>indicates that the antibody can be used "without the antigen retrieval,
>while pretreatment by heating sometimes gives better staining."  What in
the
>heck is that supposed to mean?