Dataset Information

Blocking effect of an immuno-suppressive agent, cynarin, on CD28 of T-cell receptor.

ABSTRACT: Cynarin, a potential immunosuppressant that blocks the interaction between the CD28 of T-cell receptor and CD80 of antigen presenting cells, was found in Echinacea purpurea by a new pharmaceutical screening method: After Flowing Through Immobilized Receptor (AFTIR; Dong et al., J Med Chem, 49: 1845-1854, 2006). This Echinacea component is the first small molecule that is able to specifically block "signal 2" of T-cell activation.In this study, we used the AFTIR method to further confirm that cynarin effectively blocked the binding between CD80 of B-cells and CD28 of T-cells, and provide details of its mechanism of action.The experimental results showed that cynarin blocked about 87% of the CD28-dependent "signal 2" pathway of T-cell activation under the condition of one to one ratio of T-cell and B-cell in vitro. Theoretical structure modeling showed that cynarin binds to the "G-pocket" of CD28 (Evans et al., Nat Immunol, 6:271-279, 2005), and thus interrupts the site of interaction between CD28 and CD80.These results confirm both that AFTIR is a promising method for screening selective active compounds from herbal medicine and that cynarin has great potential as an immuno-suppressive agent.

SUBMITTER: Dong GC

PROVIDER: S-EPMC2701378 | biostudies-literature | 2009 Feb

REPOSITORIES: biostudies-literature

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Blocking effect of an immuno-suppressive agent, cynarin, on CD28 of T-cell receptor.

Dong Guo-Chung GC Chuang Ping-Hsien PH Chang Kai-chun KC Jan Pey-shynan PS Hwang Pei-Ing PI Wu Huan-Bin HB Yi Myunggi M Zhou Huan-Xiang HX Chen Hueih Min HM

Pharmaceutical research 20081107 2

<h4>Purpose</h4>Cynarin, a potential immunosuppressant that blocks the interaction between the CD28 of T-cell receptor and CD80 of antigen presenting cells, was found in Echinacea purpurea by a new pharmaceutical screening method: After Flowing Through Immobilized Receptor (AFTIR; Dong et al., J Med Chem, 49: 1845-1854, 2006). This Echinacea component is the first small molecule that is able to specifically block "signal 2" of T-cell activation.<h4>Methods</h4>In this study, we used the AFTIR me ...[more]

PMID: 18989760

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Dataset Information

Blocking effect of an immuno-suppressive agent, cynarin, on CD28 of T-cell receptor.

Publications

Blocking effect of an immuno-suppressive agent, cynarin, on CD28 of T-cell receptor.

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