Abstract
Human whole blood is made up of 93-96% red blood cells (RBCs), 4-7% platelets and 0.1-0.2% leukocytes consisting mainly of granulocytes, lymphocytes and monocytes. Due to the low frequency of lymphocyte subsets within whole blood, their isolation typically requires a pre-processing step such as Lymphoprep™ or hypotonic lysis to deplete RBCs prior to cell isolation. We have therefore developed a new, fully immunomagnetic method for the negative selection of untouched cells directly from whole blood, without the need for any pre-processing steps. The EasySep™ Direct procedure involves labeling RBCs, platelets and unwanted leukocytes present in human whole blood with antibody complexes and magnetic particles. The magnetically labelled unwanted cells are separated from the untouched desired cells using an EasySep™ magnet by simply pouring or pipetting the desired cells into a new tube. In just 25 minutes, purities of 92-99% total lymphocytes, 93-98% T cells, 87-97% CD4+ T cells, 75-91% CD8+ T cells, 91-99% B cells, 87-98% naïve B cells and 65-84% NK cells can be achieved with little to no residual RBC contamination. The isolation of cells directly from whole blood will enable rapid access to highly purified cells immediately ready for downstream functional assays with minimal sample handling.