Detection of relapse by sequential monitoring of chimerism in circulating XXXX + cells.

@entity1 @entity8 @entity1861 @entity41 @entity5 @entity3052 @entity1778 @entity2280 @entity2213
Relapse of the underlying @entity5 represents one of the major causes of treatment failure in @entity1 treated with @entity8 , especially in @entity1 with @entity3052 . Detection of @entity41 ( @entity41 ) after allogenic @entity8 ( @entity8 ) is important to schedule therapeutic intervention, e.g. donor lymphocyte infusion. We asked, whether chimerism analysis in circulating @entity2280 + cells might be a feasible method to monitor @entity41 in @entity1 after allogeneic @entity8 . Eighty-seven @entity1 undergoing allogeneic @entity8 were prospectively analyzed. @entity2280 + cells were prepared from peripheral blood samples and sorted after immunomagnetic preenrichment. Results were correlated to overall chimerism and results of nested RT-PCR for the @entity1861 rearrangement in Ph1-cases. In the 87 @entity1 a median of 8 analyses (range 2-22) covering a median period of 295 days (range 28-1152) were performed. A hematological relapse was observed in 22/84 engrafting @entity1 (26%). In twenty @entity1 , the relapse was detected in the @entity2280 + fraction, in 14 of these @entity1 , donor chimerism in @entity2280 + cells decreased 12-97 days (median 52 days) before the clinical diagnosis. In two cases, @entity2280 + chimerism failed to demonstrate the relapse. In @entity1 with relapsing CML, the decrease of donor @entity2280 + cells was associated with reappearance of @entity1861 transcripts. Treatment (reduction of immunosuppression, DLI or @entity2213 ) was associated with an increase of donor derived @entity2280 + cells and clearance of @entity1861 positive cells. Sequential chimerism analysis in @entity2280 + cells is feasible and sensitive, allowing early detection of relapse and monitoring of therapeutic intervention. This method appears especially useful in @entity1 with high risk @entity1778 lacking other markers for detection of @entity41 .
