OPTIMAL PRIMER SELECTION FOR CLONALITY ASSESSMENT BY POLYMERASE CHAIN-REACTION ANALYSIS .2. FOLLICULAR LYMPHOMAS

Prior studies have shown variable success in amplification of monoclon al B-cell populations from follicular lymphomas (FLs) of germinal cent er cell origin using the polymerase chain reaction (PCR). We examined 60 FLs by the PCR to determine optimal primer selection for detection of clonal immunoglobulin heavy chain gene (IgH) rearrangements in this common group of B-cell lymphomas. Each primer set included a 3' IgH j oining region consensus primer; the 5' primer was different in each re action. The first-line panel included the following: Set 1, bcl-2 majo r breakpoint region (mbr) primer; Set 2, bcl-2 minor cluster region (m cr) primer; Set 3, IgH variable region framework III consensus primer; and Set 4, seven separate IgH variable region framework I family-spec ific primers. A reserve panel also was used. The efficiency of monoclo nal B-cell population amplification differed among primer sets. The bc l-2-targeted primer pairs (Sets 1 and 2) were most efficient and ampli fied 42 (70%) of 60 cases. Of these, the mbr and mcr primer sets detec ted monoclonality in 38 and four cases, respectively. Set 3 amplified monoclonal B-cell populations in 31 (52%) cases and Set 4 detected sim ilar populations in only 27 (45%) samples. When results from primer Se ts 1, 2, and 3 were combined, 49 of 60 (82%) FLs showed evidence of B- cell monoclonality by the PCR, Three of the 11 negative cases were doc umented as monoclonal with primer Set 4, and three additional samples were amplified only with our reserve panel. Overall, B-cell monoclonal ity was detected in 55 of 60 (92%) ms. Our data suggest that clonal B- cell populations from more than 80% of ms can be amplified with the us e of primer Sets 1 and 3. In initially nonamplifiable ms additional pr imer combinations, such as those directed at the other two framework r egions within the IgH variable region genes, can augment the detection rate to greater than 90% of cases. Copyright (C) 1994 by W.B. Saunder s Company