PCR analysis of microdissected specimens.
(A) Example of a monoclonal pattern of JH gene rearrangement of cells within the follicles after laser-based microdissection in 1 patient with FCL (patient 9). Lanes: 1 to 5, 5 different follicles; 6 to 11, 6 different interfollicular areas; 12, negative control (no DNA, external PCR run); 13, positive control (cutaneous B-cell lymphoma); 14, negative control (no DNA, internal PCR run); 15, molecular ladder. (B) Example of a polyclonal pattern of JH gene rearrangement of follicle center cells and interfollicular cells after laser-based microdissection in 1 patient with FCL (patient 6). Lanes: 1, molecular ladder; 2 to 7, 6 different follicles; 8 to 12, 5 different interfollicular areas; 13, negative control (no DNA, external PCR run); 14, positive control (cutaneous B-cell lymphoma). (C) Marginal zone lymphoma reveals monoclonality of interfollicular cells and polyclonal pattern of reactive germinal centers. Lanes: 1 to 4, reactive germinal centers; 5 to 9, interfollicular areas; 10, molecular ladder. One of the bands in lane 4 may represent follicular colonization by neoplastic marginal zone cells.
