PCR clonality analysis.
CDR3-related PCR products were obtained by amplifying lymphoma biopsy DNA with consensus FW3 and JH1 primers. Small aliquots of the resultant products were also secondarily amplified with FW3 and more internal JH2 primer. Shown are products from both FW3-JH1 and FW3-JH2 reactions for 2 cases and a polyclonal control after electrophoresis in an 8% acrylamide gel and staining with ethidium bromide. Prominent single monoclonal bands are seen in each case, along with fainter polyclonal ladders that reflect background B cells with different sized CDR3s that are also invariably present. The smaller sizes of the FW3-JH2 generated monoclonal bands simply reflect the more 5′ location of JH2 relative to JH1. Secondary amplifications with JH2 were performed to potentially enhance weaker monoclonal signals relative to the polyclonal background and to determine whether the JH2 primer would work with the clonalVH gene in PCR reactions to obtained more full length VH products.