CD8(+) T cells secreting type 2 lymphokines are defective in protection against viral infection

Effector T cells secreting type 1 and/or type 2 lymphokines (Tc1, Tc0, Tc2) were generated in vitro from CD8(+) T cells of mice with a transgenic TCR recognizing lymphocytic choriomeningitis virus (LCMV) glycoprotein to compa re their effector function in vitro and in vivo, Tc1, Tc2, and Tc0 showed s imilar Fas- and perforin-mediated cytotoxicity in vitro. Upon adoptive tran sfer, Tc2 and Tc0 effecters were less efficient than Tc1 at controlling LCM V or recombinant vaccinia virus expressing the LCMV glycoprotein in vivo, T c2 and Tc0 had decreased surface VLA-4 density and deficient activation-ind uced LFA-1/ICAM-1-dependent homotypic adhesion in vitro, Therefore, the red uced antiviral activity in vivo of Tc2 and Tc0 compared with Tc1 is not due to reduced cytotoxic activity or IFN-gamma secretion but may be explained by defective homing to the target organ due to decreased expression and/or lower activity of adhesion molecules. (C) 2000 Academic Press.