Lymphokine production by peripheral blood leucocytes: quantitation of T-cell growth factor activity for assessment of immune response capability.

Mitogen stimulation of as few as 200,000 human peripheral blood leucocytes (PBL) in 0.2 ml volumes produces highly active lymphokine supernatants. The lymphokine activity measured is T-cell growth factor. Under optimum conditions of PHA-P concentration, serum source and concentration, and time, activity is detectable to a dilution of between 1/250 and 1/700 for lymphokine supernatants from PBL of normal donors. Lymphokine supernatants prepared from PBL of donors previously treated with the immunosuppressive regimes of radiotherapy and/or chemotherapy had activities that were between 13% and 66% of normal controls. Lymphokine production as a quantitative measure of immune capability is discussed.