The novel calcineurin inhibitor CN585 has potent immunosuppressive properties in stimulated human T cells.
The Ca2+/calmodulin-dependent protein phosphatase calcineurin is a key mediator in antigen-specific T cell activation. Thus, inhibitors of calcineurin, such as cyclosporin A or FK506, can block T cell activation and are used as immunosuppressive drugs to prevent graft-versus-host reactions and autoimmune diseases. In this study we describe the identification of 2,6- diaryl-substituted pyrimidine derivatives as a new class of calcineurin inhibitors, obtained by screening of a substance library. By rational design of the parent compound we have attained the derivative 6-(3,4-dichloro-phenyl)-4-(N,N-dimethylaminoethylthio)-2-phenyl-pyrimidine (CN585) that noncompetitively and reversibly inhibits calcineurin activity with a K(i) value of 3.8 mum. This derivative specifically inhibits calcineurin without affecting other Ser/Thr protein phosphatases or peptidyl prolyl cis/trans isomerases. CN585 shows potent immunosuppressive effects by inhibiting NFAT nuclear translocation and transactivation, cytokine production, and T cell proliferation. Moreover, the calcineurin inhibitor exhibits no cytotoxicity in the effective concentration range. Therefore, calcineurin inhibition by CN585 may represent a novel promising strategy for immune intervention.
Erdmann
Frank
F
Max Planck Research Unit for Enzymology of Protein Folding, Weinbergweg 22, D-06120 Halle/Saale. erdmann@enzyme-halle.mpg.de
Weiwad
Matthias
M
Kilka
Susann
S
Karanik
Magdalena
M
Pätzel
Michael
M
Baumgrass
Ria
R
Liebscher
Jürgen
J
Fischer
Gunter
G
D019703:Calcineurin / Q000378:metabolism; D065095:Calcineurin Inhibitors; D049109:Cell Proliferation / Q000187:drug effects; D016207:Cytokines / Q000096:biosynthesis; D004353:Drug Evaluation, Preclinical; D004791:Enzyme Inhibitors / Q000737:chemistry / Q000276:immunology / Q000378:metabolism / Q000494:pharmacology*; D006801:Humans; D007114:Immunization; D007166:Immunosuppressive Agents / Q000737:chemistry / Q000276:immunology / Q000378:metabolism / Q000494:pharmacology*; D042541:Intracellular Space / Q000187:drug effects / Q000378:metabolism; D019169:Jurkat Cells; D007963:Leukocytes, Mononuclear / Q000276:immunology; D050778:NFATC Transcription Factors / Q000378:metabolism; D010766:Phosphorylation / Q000187:drug effects; D011743:Pyrimidines / Q000737:chemistry / Q000276:immunology / Q000378:metabolism / Q000494:pharmacology*; D013379:Substrate Specificity; D013601:T-Lymphocytes / Q000166:cytology / Q000187:drug effects* / Q000276:immunology*
C546889:6-(3,4-dichlorophenyl)-4-(N,N-dimethylaminoethylthio)-2-phenylpyrimidine; D065095:Calcineurin Inhibitors; D016207:Cytokines; D004791:Enzyme Inhibitors; D007166:Immunosuppressive Agents; D050778:NFATC Transcription Factors; D011743:Pyrimidines; D019703:Calcineurin; C030986:pyrimidine