PATTERNS AND DISTRIBUTION OF EUCHRYSINE-BINDING GRAINS IN NONSTIMULATED HUMAN PERIPHERAL T-LYMPHOCYTES AND NON-T-LYMPHOCYTES

The patterns of supravital staining with euchrysine, a fluorescent stain thought to bind selectively to lysosomal membranes, were evaluated in resting human lymphocytes separated on the basis of their ability to form spontaneous rosettes with sheep red blood cells in thymus-dependent (T) and thymus-independent (non-T) subpopulations. Two basic staining patterns were found in unseparated lymphocyte populations: type I, small fluorescent granules in a conglomerate form, usually located in a single spot close to the cell membrane; and type II, discrete fluorescent granules dispersed over the entire cytoplasm. The overwhelming majority of non-T lymphocytes displayed the type II pattern. Within the T cell subpopulations type I and type II patterns were found in proportions which were subject to donor-to-donor variability.