A new method to make nuclei or cell microarrays.

We invented a new method to make microarrays using nuclei extracted from paraffin-embedded tissues or cultured cells. A blank recipient paraffin block with 10 x 10 cores was constructed and sectioned to make the mold for the cell arrays. The sections of paraffin were mounted on poly-L-lysine-coated slides. Prepared nuclei or cells were injected into the cores of the paraffin mold. The slides were dried and dewaxed and nuclei or cell arrays were made. Using this method, we successfully made microarrays of nuclei extracted from diffuse large B-cell lymphoma paraffin-embedded tissues, nasopharyngeal cancer and lymphoma cell lines. This technique resulted in a paraffin-embedded cell preparation that yielded a cell density of approximately 500 to 1000 or 800 cells on average per 0.6-mm-diameter core. The microarrays were successfully used in fluorescence in situ hybridization, mRNA in situ hybridization, and cytohistochemical staining.