We have been using Novocastra's mAb (clone 1F6) following high pH retrieval, along with DAKO's EnVision+ detection and their DAB+ for chromogen.  The antibody (in our hands) does not have a high titer; we it at 1:20 for 30' or 1:100 overnight.  CD4 is one of the more difficult antigens to label in formalin-fixed, paraffin-embedded tissue.  It's my opinion that freshly cut tissue sections produce optimal labeling.

R. Cartun

>>> Aneeta Patel  01/08/02 12:51PM >>>
Hi
Does anybody have a method/source of antibody for CD4 on human paraffin embedded tissues.
thanks