Efficient recovery of clonogenic stem cells from solid tumors and occult metastatic deposits

We describe the use of enzymes combined with brief, sequential mechanical disruptions in a Tekmar Stomacher blender for the recovery of clonogenic neoplastic cells from solid tumors, lungs, and livers. The method has yielded 3 X 10(8) to 5 X 10(8) total cells and 1.2 X 10(6) to 17 X 10(6) clonogenic cells per gram of tissue from three different mouse mammary tumor subpopulations growing in the subcutis. The clonogenic cell yields represent a 4- to 13-fold increase over our previous best method of tumor disaggregation. The increase in total cells recovered, while not as dramatic (up to 3-fold), was statistically significant for two of the three tumor lines. We were also able to efficiently recover 125I-iododeoxyuridine labelled neoplastic cells from lungs and livers after injecting the cells intravenously. Over half of the total radiolabel present in these organs prior to disaggregation could be recovered in the cell suspensions obtained.