PCR of microdissected bcl-2⁺ and bcl-2⁻follicles from 5 cases.

(A-E) IgH⁻ FRIII PCR. (F) BCL2/JHPCR. (A,F) Case no. 17. (B) Case no. 8. (C) Case no. 11. (D) Case no. 6. (E) Case no. 2. MW indicates molecular weight standard; +, microdissected bcl-2⁺ follicles; –, microdissected bcl-2⁻ follicles; W, whole intact tissue section without microdissection. In case nos. 17, 8, 11, and 6, reproducible single or double discrete clonal bands (arrows) with or without a background ladder were generated from bcl-2⁺ GCs, whereas a polyclonal ladder was generated from bcl-2⁻ GCs. Case no. 11 (C) contained 2 separate distinct clonal bands. Case no. 2 (E) showed a polyclonal ladder pattern from both bcl-2⁺ and bcl-2⁻ follicles. (F) A BCL-2 gene rearrangement at the major breakpoint region was identified from microdissected bcl-2⁺ GCs (+) and the whole (W) intact tissue section without microdissection, but was negative in bcl-2⁻ (−) GCs (case no. 17).