LF 15-0195 Inhibits the Development of Rat Central Nervous System Autoimmunity by Inducing Long-Lasting Tolerance in Autoreactive CD4 T Cells

Abstract

Experimental autoimmune encephalomyelitis (EAE) is a T cell-dependent autoimmune disease induced in susceptible animals by a single immunization with myelin basic protein (MBP). LF 15-0195 is a novel immunosuppressor that has been shown to have a potent immunosuppressive effect in several pathological manifestations. The purpose of this study was to investigate the effect of this drug on the induction and progression of established rat EAE and to dissect the mechanisms involved. We show that LF 15-0195 administration at the time of MBP immunization reduces the incidence and severity of EAE in Lewis rats. This drug also inhibits ongoing and passively induced EAE, indicating that LF 15-0195 affects already differentiated pathogenic lymphocytes. Compared with lymph node cells from untreated rats, lymphocytes from MBP-immunized rats treated with LF 15-0195 proliferated equally well in response to MBP in vitro, while their ability to produce effector cytokines and to transfer EAE into syngeneic recipients was significantly reduced. This phenomenon is stable and long-lasting. Indeed, neither IL-12 nor repeated stimulation with naive APC and MBP in vitro rendered MBP-specific CD4 T cells from protected rats encephalitogenic. In conclusion, LF 15-0195 treatment suppresses EAE by interfering with both the differentiation and effector functions of autoantigen-specific CD4 T cells.

Targeting Experimental Autoimmune Encephalomyelitis Lesions to a Predetermined Axonal Tract System Allows for Refined Behavioral Testing in an Animal Model of Multiple Sclerosis

“…24,25 Rats were anesthetized by inhalation anesthesia and injected subcutaneously at the base of the tail with a total volume of 100 l of MBP (10 to 50 g per rat diluted in saline) emulsified in complete Freund's adjuvant (CFA) containing 5 mg/ml of mycobacterium tuberculosis H37RA (250 g per rat; Difco, Detroit, MI). For control experiments rats were injected subcutaneously at the base of tail with a total volume of 100 l of saline emulsified in CFA.…”

LF 15-0195 Treatment Protects against Central Nervous System Autoimmunity by Favoring the Development of Foxp3-Expressing Regulatory CD4 T Cells

“…We previously demonstrated that the reduced ability of MBP-specific CD4 T cells from LF 15-0195-treated rats to transfer EAE is a stable phenomenon and could not be explained by a difference in cytokine production (17). Indeed, LFMBP lines generated in the presence of IL-12 have a cytokine profile comparable to encephalitogenic MBP lines but are nevertheless incapable of transferring EAE.…”

“…LF 15-0195 has demonstrated therapeutic efficacy in animal models of allotransplantion (9 -12), xenotransplantation (13,14), and autoimmune diseases (15)(16)(17). In EAE, we previously demonstrated that LF 15-0195 inhibits the effector phase of EAE by reducing the encephalitogenicity of MBP-specific CD4 T cells (17).…”

“…We previously reported that both clinical and histological manifestations of EAE were significantly suppressed by s.c. administration of LF 15-0195 to MBP-immunized LEW rats (17). In this study, we investigated the effect of this treatment on the resistance phase of EAE (Table I).…”

“…In some experiments, the recipients were lightly irradiated (250 rad). LF 15-0195 (Fournier Laboratories) was prepared in saline solution, adjusted at pH 7.2, and 300 l was administered s.c. using a protocol previously shown to fully prevent EAE (17). The animals were injected daily with LF 15-0195 at 1 mg/kg for 30 days, starting the day of immunization.…”