Disclosed is a method of making a composition comprising cells, comprising: (a) contacting said cells with a solution comprising dextran and human serum albumin (HSA) to form a cell-containing solution； (b) filtering the cell-containing solution； (c) if said cell-containing solution comprises greater than 10 ± 3 x 106 cells per milliliter, diluting said cells to no more than 10 ± 3 x 106 cells per milliliter with a first dilution solution comprising dextran； and (d) optionally diluting the cell-containing solution with a second dilution solution comprising dextran but not comprising HSA, thereby making a composition comprising cells.
