Figure 2. Isolation of human primary CD4T⁺ cells by histopaque density gradient.

A. Slowly layer the blood (containing the RosetteSep Cocktail and diluted to half with PBS + 2% FBS) on top of histopaque density gradient. Centrifuge for 20 min at 800 × g, RT, with brake off. B. CD4⁺ T cells are contained in the white ring, below the plasma phase, but above the histopaque and red cell phases. Carefully pipet out the ring.