ENDOTOXIN-INDUCED UVEITIS IN MICE .2. ENHANCEMENT OF EIU BY INTERLEUKIN-1

In our previous study we reported that the systemic injection of endot oxin in C3H/HeN mice produces uveitis (endotoxin-induced uveitis, EIU) , and that CD4+ T lymphocytes play an important role in its developmen t. In the present study, we tried to induce EIU in various strains of mice and investigated the effect of pretreatment with interleukin-1 (I L-1) on EIU. C3H/HeN, C3H/HeJ, BALB/c and BALB/c-nu/nu mice were injec ted with endotoxin into the hind footpads. Twenty-four hours later, th e cell number and protein concentration in aqueous humor were determin ed. In some mice of each strain, IL-1 was injected subcutaneously and/ or anti-Thy-1.2 antibody was administered intraperitoneally, prior to the injection of endotoxin. In C3H/HeN and BALB/c mice, EIU was induce d and was markedly enhanced by IL-1, while the enhancement of EIU in C 3H/HeN mice was significantly suppressed by pretreatment with anti-Thy -1.2 antibody. Very mild EIU developed in BALB/c-nu/nu mice, but this EIU was not enhanced by IL-1. In C3H/HeJ mice, EIU was not induced eve n after pretreatment with IL-1. These results indicate that T lymphocy tes play an important role in EIU induced by endotoxin alone as well a s in EIU enhanced by pretreatment with IL-1 in C3H/HeN and BALB/c mice . However, other factors appear also to be involved in the development of EIU.