Induction of cellular NF-κB and NFAT activation leads to BLyS protein expression in normal B lymphocytes and low-grade follicular lymphoma (FL) cells. (A) EMSA analysis of normal G0 and activated peripheral blood B cells using the NF-κB or NFAT binding site oligonucleotides from the BLYS promoter. (B) RT-PCR analysis of BLyS expression in normal peripheral blood B cells. (C) Western blot analysis of BLyS in normal peripheral blood B cells. (D) EMSA analysis of tumor cells from a patient with follicular lymphoma (> 90% small cleaved cells: grade 1 FL) using oligonucleotide probes from BLYS-NF-κBor BLYS-NFAT binding sites on the BLYS promoter. (E) RT-PCR analysis of BLyS expression in the FL cells (described in panel D). (F) Western blot analysis of BLyS expression in follicular lymphoma (small cleaved cell lymphoma, grade 1) patient biopsy cells. Actin was used as loading control. BLyS protein expression levels were analyzed by BioMax 1D software as before.