CLONALITY ANALYSIS OF DEFINED B-CELL POPULATIONS IN ARCHIVAL TISSUE-SECTIONS USING MICRODISSECTION AND THE POLYMERASE CHAIN-REACTION

A simple microdissection technique involving the use of a drawn-out gl ass pipette was developed for isolation of defined cell subsets from t issue sections. Using this technique and the polymerase chain reaction (PCR), clonally rearranged immunoglobulin (Ig) heavy chain genes were reliably amplified in single neoplastic follicles or few hundreds of tumour cells isolated from archival haematoxylin and eosin or immunost ained sections of B-cell lymphomas. A polyclonal nature was consistent ly demonstrated in reactive lymphoid follicles or interfollicular reac tive B-cells within the same lymphoma sections. Microdissection of lym phoma cells from within foci of chronic inflammation improved the reso lution of tumour-specific PCR products by reducing amplification of ba ckground polyclonal B-cell sequences. The combination of microdissecti on and PCR techniques, therefore, provides an important tool for the i nvestigation of B-cell lymphomas and also allows simple and specific a ccess for other molecular genetic analyses of different cell subsets o n tissue sections.