Randall S. Davis, M.D. University of Alabama at Birmingham

THERAPY/ PROGNOSTIC

Potential Role of FCRL2 as a Surrogate Marker of IgVH Mutation in CLL

Update:

Over the last 9 months we have made substantial progress in our effort to define the biological importance of FCRL2 in CLL. We were fortunate to publish our initial results concerning this receptor last February in the journal Blood which was highlighted by an accompanying commentary. This publication was the first to identify the FCRL2 protein as a useful prognostic marker in CLL. Since CLL Global funding commenced, we have been continually recruiting blood samples from individuals with CLL and testing additional reagents to optimize staining for the FCRL2 molecule on CLL B cells. So far our initial anti-FCRL2 reagent remains the best for staining purposes. Recruitment of additional CLL patients into the study has revealed consistency with our original observations that a higher level of FCRL2 staining on the surface of CLL cells is predictive of a more favorable clinical course.

We have also been extensively surveying different human tissues to define the normal expression pattern of the FCRL2 protein. We have made a very interesting observation concerning FCRL2 expression by a distinct population of blood cells involved in immune system memory. FCRL2 appears to mark a unique type of memory B cell with features similar to mutated CLL subtype B cells. Thus, in addition to its promise as a useful prognostic marker, FCRL2 could also be helpful for defining a pre-transformed CLL counterpart.