In situ amplification: detection of target sequences in whole tissues

Using the polymerase chain reaction (PCR) specific gene target sequences can be routinely amplified from isolated nucleic acids. However, this does not allow the investigator the option of correlating the presence of amplified product with cellular localization. When PCR is performed in situ and coupled with either a direct or indirect method of detecting amplified product, a powerful investigative tool exists. Owing to variability in results, the features of in situ PCR which are most likely to contribute to these effects are described. Also described is an amplification chamber for localized in situ amplification (LISA) which utilizes tissue culture cloning rings and allows for the amplification of gene target sequences in specific regions of paraffin-embedded tissue sections.