From: Proceedings 10th World Congress of Cryosurgery
Enhanced Cryo-destruction with Antifreeze Proteins.
Homayoon Koushafar, Linda Pham, Boris Rubinsky
Cryosurgery employs freezing to destroy undesirable tissues. However, it is well established that indiscriminant freezing does not
necessarily destroy tissue and that tissue destruction depends on the thermal conditions during freezing. Usually, tissues survive the
thermal conditions on the outer edge of the frozen lesion and usually, the extent of freezing does not necessarily correspond to the extent
of tissue destruction. We have discovered that a family of protein's known as "antifreeze proteins: (AFP), have the ability to induce
complete frozen tissue destruction regardless of the thermal conditions during freezing. The effect of the AFP's is only a function of their
concentration in tissue. It appears at a dose of about 10mg/ml and higher, the AFP's modify the structure of ice crystals to needle like,
micron size crystals. These spicular ice crystals are only a function of concentration, are independent on the thermal conditions during
freezing and induce complete cell destruction by freezing. The effects of the antifreeze proteins will be shown in cellular suspensions and in
tissues and their mechanism of action discussed. It will be shown that in AFP adjuvant cryosurgery the extent of freezing corresponds
with the extent of tissue destruction. Combining new imaging techniques with the effect of antifreeze proteins could make cryosurgery the
most precise minimally invasive surgical technique currently known.