Tissue disaggregation of human kidney cells followed by purification on isokinetic and isopyknic gradients.

Five normal human kidneys were disaggregated with three combinations of enzymes. The combination of collagenase 0.5 mg per ml of 11 additional kidneys. The viability of cells in suspension ranged from 75 to 94 per cent with a mean viability of 85.3 +/- 1.6 per cent. Disaggregated kidney cells were fractionated in isopyknic and isokinetic gradients. After isokinetic sedimentation, kidney tubule cells were predominantly in fraction 22 +/- 1 whereas lymphocytes were consistently located in fraction 8 +/- 1. Kidney epithelial cells were enriched to a 90.4 +/- 2.2 per cent (79.0 to 96.0 per cent) purity by isokinetic gradient centrifugation. Controlled rate freezing of cells provided material for repeated experiments, and short-term tissue culture before cell separation increased the proportion of viable cells in suspension.