Send to

Choose Destination
See comment in PubMed Commons below
J Pharmacol Exp Ther. 2003 Jun;305(3):1150-62. Epub 2003 Mar 6.

An assessment of the mechanistic differences between two integrin alpha 4 beta 1 inhibitors, the monoclonal antibody TA-2 and the small molecule BIO5192, in rat experimental autoimmune encephalomyelitis.

Author information

  • 1Biogen, Inc., 12 Cambridge Center, Cambridge, MA 02142, USA.


Integrin alpha 4 beta 1 plays an important role in inflammatory processes by regulating the migration of lymphocytes into inflamed tissues. Here we evaluated the biochemical, pharmacological, and pharmacodynamic properties and efficacy in experimental autoimmune encephalomyelitis (EAE), a model of multiple sclerosis, of two types of alpha 4 beta 1 inhibitors, the anti-rat alpha 4 monoclonal antibody TA-2 and the small molecule inhibitor BIO5192 [2(S)-[[1-(3,5-dichloro-benzenesulfonyl)-pyrrolidine-2(S)-carbonyl]-amino]-4-[4-methyl-2(S)-(methyl-[2-[4-(3-o-tolyl-ureido)-phenyl]-acetyl]-amino)-pentanoylamino]-butyric acid]. TA-2 has been extensively studied in rats and provides a benchmark for assessing function. BIO5192 is a highly selective and potent (KD of <10 pM) inhibitor of alpha 4 beta 1. Dosing regimens were identified for both inhibitors, which provided full receptor occupancy during the duration of the study. Both inhibitors induced leukocytosis, an effect that was used as a pharmacodynamic marker of activity, and both were efficacious in the EAE model. Treatment with TA-2 caused a decrease in alpha 4 integrin expression on the cell surface, which resulted from internalization of alpha 4 integrin/TA-2 complexes. In contrast, BIO5192 did not modulate cell surface alpha 4 beta 1. Our results with BIO5192 indicate that alpha 4 beta 7 does not play a role in this model and that blockade of alpha 4 beta 1/ligand interactions without down-modulation is sufficient for efficacy in rat EAE. BIO5192 is highly selective and binds with high affinity to alpha 4 beta 1 from four of four species tested. These studies demonstrate that BIO5192, a novel, potent, and selective inhibitor of alpha 4 beta 1 integrin, will be a valuable reagent for assessing alpha 4 beta 1 biology and may provide a new therapeutic for treatment of human inflammatory diseases.

[PubMed - indexed for MEDLINE]
Free full text
PubMed Commons home

PubMed Commons

How to join PubMed Commons

    Supplemental Content

    Full text links

    Icon for HighWire
    Loading ...
    Write to the Help Desk