Cell experiment:

Purified CD11b+ cells from laquinimod- or vehicle-treated mice are cultured with naive CD4+ cells isolated from laquinimod- or vehicle-treated 2D2 mice and antigen (MOG p35-55, 20 μg/mL). Cells are cultured in 96-well microtitre plates at a concentration of 0.25×106 cells/mL. Culture medium consisted of RPMI 1640 supplemented with L-glutamine (2 mM), sodium pyruvate (1 mM), penicillin (100 U/mL), streptomycin (0.1 mg/mL), 2-mercaptoethanol (5×10-5 M) and 10% (v/v) fetal bovine serum. Cells are incubated for 48 h and pulsed for 18 h with 1 μCi per well of [3H]-thymidine before harvesting.

Animal experiment:

Seven to 10-week-old female C57BL/6, DBA/1 or SJL/J mice are injected subcutaneously with 50 μg MOG p35-55, 50 μg rMOG or 100 μg PLP p139-151, respectively, in complete Freund's adjuvant. After immunization and 2 days later, mice receive 200 ng (C57BL/6) or 100 ng (SJL/J) pertussis toxin intraperitoneally (i.p.). For adoptive transfer, donor SJL/J mice are immunized as described above and treated daily with laquinimod or vehicle. 10 days later, cells from draining lymph nodes and spleen are isolated, re-stimulated for 48 h (20 μg/mL PLP p139-151), and injected i.p. into naive SJL/J recipients (107 cells per mouse). Animals are observed daily and clinical scores are assessed as follows: 0, no signs; 1, decreased tail tone; 2, mild monoparesis or paraparesis; 3, severe paraparesis; 4, paraplegia and/or quadraparesis; and 5, moribund or death.

ABR-215062 is an orally active immunoregulator. Experimental autoimmune encephalomyelitis (EAE) is an inflammatory autoimmune disease of the CNS that can be elicited in rodents and represents the major animal model for the study of multiple sclerosis (MS).

In vitro: ABR-215062 was shown to completely inhibit the development of murine acute experimental autoimmune encephalomyelitis (EAE) [1].

In vivo: ABR-215062 dose-dependently inhibited disease and showed better disease inhibitory effects as compared to roquinimex (Linomide). Furthermore, ABR-215062 inhibited the inflammation of both CD4+ T cells and macrophages into central nervous tissues [2].

Clinical trial: Randomized, controlled clinical trials in relapsing MS demonstrate a dose–response effect of ABR-215062 on disease activities, indicated by reduced clinical relapse rate, number of brain MRI active lesions, and sustained disability and brain atrophy [3].

References:
[1] Brunmark C, Runstrom A, Ohlsson L, Sparre B, Brodin T, Astrom M, Hedlund G.  The new orally active immunoregulator laquinimod (ABR-215062) effectively inhibits development and relapses of experimental autoimmune encephalomyelitis. J Neuroimmunol. 2002 Sep;130(1-2):163-72.
[2] Yang JS, Xu LY, Xiao BG, Hedlund G, Link H.  Laquinimod (ABR-215062) suppresses the development of experimental autoimmune encephalomyelitis, modulates the Th1/Th2 balance and induces the Th3 cytokine TGF-beta in Lewis rats. J Neuroimmunol. 2004 Nov;156(1-2):3-9.
[3] Haggiag S, Ruggieri S, Gasperini C.  Efficacy and safety of laquinimod in multiple sclerosis: current status. Ther Adv Neurol Disord. 2013 Nov;6(6):343-52.