Increased sensitivity of the rosette-forming reaction of human T lymphocytes with sheep erythrocytes afforded by papain treatment of the sheep cells.

Human T lymphocytes are known to adhere to sheep erythrocytes. This affinity reaction was found to be consistently increased following treatment of the sheep cells with papain. Reactions with treated erythrocytes were more stable and involved higher percentages of lymphocytes. Using a double marker system of papain-treated sheep erythrocytes together with Fc rosettes as a presumptive B-cell marker, there was an overlap population of only 1% lymphocytes. Sheep erythrocytes treated with papain therefore appear to remain specifically adherent to human T lymphocytes.