DBA.44 works very well in our hands... using mild 0.5% pepsin digestion,
10-12min... @ 1:200 with Powervision+ detection.  Please note that this is a
IgM isotype monoclonal so it might be important that your seconday link
antibody include some anti-IgM.
It's important to have a "known positive" case to use as a control. 

DBA.44, a B subset antibody, also CD72, reacts with very few normal
cells...however, 50-97%(depending who you read) of hairy cell leukemias(HCL)
cases are positive; about 35% of low grade B-cell lymphomas are positive;
and about 30-80%(depending on who you read) of splenic lymphomas are
positive.

The antibody is NOT specific for HCL since it is positve also in some
marginal cell lymphomas(MZL) and large cell lymphomas.

TRAP(tartrate-resistant acid phosphatase) by IHC is a very good way to
detect HCL's... the combination of +HBA.44 and +TRAP is considered
specific??(what is specific?) for HCL.

Robert L. Lott, HTL(ASCP)
      Manager, Anatomic Pathology
      Baptist Health System
      800 Montclair Road
      Birmingham, AL  35213
      205-592-5388
      205-592-5646 (fax)
      robert.lott@bhsala.com