Target activated microtransfer

Abstract

A method of removing a target from a biological sample which involves placing a transfer surface in contact with the biological sample, and then focally altering the transfer surface to allow selective separation of the target from the biological sample. In disclosed embodiments, the target is a cell or cellular component of a tissue section and the transfer surface is a film that can be focally altered to adhere the target to the transfer surface. Subsequent separation of the film from the tissue section selectively removes the adhered target from the tissue section. The transfer surface is activated from within the target to adhere the target to the transfer surface, for example by heating the target to adhere it to a thermoplastic transfer surface. Such in situ activation can be achieved by exposing the biological sample to an immunoreagent that specifically binds to the target (or a component of the target). The immunoreagent can alter the transfer surface directly (for example with a heat generating enzyme carried by the immunoreagent), or indirectly (for example by changing a characteristic of the target). In some embodiments, the immunoreagent deposits a precipitate in the target that increases its light absorption relative to surrounding tissue, such that the biological specimen can be exposed to light to selectively heat the target. Alternatively, the immunoreagent is an immunofluorescent agent that carries a fluorophore that absorbs light and emits heat.