Direct fluorescent labeling of cells with fluorescein or rhodamine isothiocyanate. II. Potential application to studies of lymphocyte migration and maturation.

The effect of direct cell labeling with fluorescein or tetramethyl rhodamine isothiocyanate on lymphocyte migration is examined. In vitro conditions of labeling are defined which (1) do not significantly affect immediate or long term viability of lymphocytes (up to 2 weeks after transfer in vivo), (2) do not alter normal lymphocyte migration, (3) do not affect expression or detectability of surface antigens, and (4) permit direct visualization and counter-staining with fluorescent antibody reagents for days after intravenous injection. The potential application of this method to studies of lymphocyte migration and maturation is discussed.