Effect of phytohaemagglutinin in the leucocyte migration inhibition test as a measure of cell-mediated immunity.

Evaluation of responsiveness to phytohaemagglutinin (PHA) in the leucocyte-migration inhibition test has been extended to a greater number of patients and control subjects to explore the range of the test. The patients, mainly with sarcoidosis, were found to be less responsive than controls. The conditions of the test in terms of concentration of PHA, duration of culture, and serum concentration used were investigated and standards suggested. Intraperson variation and the influence of age were also evaluated.