Comparison of the hemocytometer and tube modifications of the leukocyte adherence inhibition assay -- II. Application of both modifications for detection of anti-tumor immunity in man.

The hemocytometer and the tube modifications of the leukocyte adherence inhibition (LAI) assay were compared under identical experimental conditions in patients with carcinoma of the larynx. In the direct test, both modifications showed adherence inhibition if patients peripheral blood leukocytes (PBL) were incubated with a larynx cancer antigen preparation. Cell-free supernatants obtained by cocultivation of patients PBL with the antigenic extract yielded positive results only in the hemocytometer modification. Those supernatants inhibited the adherence of both normal human PBL and guinea pig peritoneal cells. Human encephalitogenic protein used as antigenic preparation in both direct and indirect hemocytometer modifications caused changes in adherence too. The presented results confirm the opinion that the hemocytometer and tube LAI assays base on different mechanisms.