Leucocyte migration inhibition test and tuberculin hypersensitivity. "Escape" and some other factors influencing the clinical use.

Tuberculin hypersensitivity was evaluated in 71 Mantoux-positive and 58 Mantoux-negative persons by the leucocyte migration inhibition test. The capillary tube technique discriminated these two groups, but variability of results and overlapping of the groups were considerable. The shorter the incubation period, the better discrimination between the groups. Only after short incubation (2 h) was the correlation between the intensities of Mantoux reactions and migration inhibitions evident. The observed variability in migration areas, similar in the Mantoux-positives and controls, was the result of technical causes and variations in cells' ability to migrate. Further, in Mantoux-positive persons the migration progression (per min) increased during the first 2 h, but slowed down later on, more in controls than in chambers with antigen. Smaller migration areas in controls (early intervals) tended to produce lower migration indices than the larger ones. Finally, it was possible, using the standard score zeta, to calculate whether each individual result differed significantly from controls. By this procedure the intensity of cell-mediated immunity in individual patients could be estimated.