DIFFERENT T-CELL ACTIVATION BY STREPTOZOTOCIN AND FREUNDS-ADJUVANT INPOPLITEAL LYMPH-NODE (PLN)

A popliteal lymph node (PLN) test was further validated for predictive screening of autoimmunity-inducing drugs. Autoimmune-like T-cell acti vation of streptozotocin (STZ) was compared with the effect of Freund' s complete adjuvant (FCA), injected locally into the foot pad of BALB/ c mice. Early cell activation in enlarged PLN was monitored by flow cy tometry. Injection of both STZ and FCA markedly increased the absolute PLN cell number as well as specific T-helper (CD4(+)), T-suppressor/c ytotoxic (CD8(+)), and B (Ig(+)) subsets. However, quantitative analys is of early T-cell activation revealed important differences between S TZ-induced PLN reaction and FCA-related lymphoproliferation. At 72 h, the number of cells stained with anti-early activation marker (EAM(+); CD69(+)) increased over 10 times in STZ-enlarged nodes and only 3 tim es in the FCA-inflamed nodes. Furthermore, different cytometric profil es were noted for STZ-activated and FCA-activated cells stained with a nti-interleukin-2 receptor (IL-2R) (CD25(+)). The data suggest the app licability of early cytometric screening of enlarged PLN for predictiv e analysis detection of chemicals inducing an autoimmune-like reaction .