DIFFERENTIAL-EFFECTS OF INTERLEUKIN-12 TREATMENT ON GENE-EXPRESSION BY ALLOSTIMULATED T-CELLS FROM YOUNG AND AGED MICE

Alloantigen stimulation was used to examine the effect of interleukin (IL-12) treatment of stimulated cells from young and aged mice on the expression of mRNAs for perforin and granzyme B, two proteins known to be intimately involved in an important lytic pathway used by CTL, and mRNA for interferon (IFN)-gamma, production of which is highly stimul ated by IL-12 As reported previously, IL-12 augmented the lytic activi ty by cells from both young and aged mice, although the relative incre ase was greater for the latter. The mRNAs encoding perforin and granzy me B were both marginally enhanced at early time points (for cells fro m young mice) or throughout the stimulation (for cells from aged mice) following allo-stimulation in the presence of IL-12. The levels of au gmentation of these mRNAs was consistent with the augmentation of lyti c activity. In contrast, mRNA encoding IFN-gamma was markedly enhanced throughout stimulation in cells from animals of both age groups, corr esponding to the more substantial increase in interferon protein in re sponse to IL-12.