Involvement of P-glycoprotein in the release of cytokines from peripheral blood mononuclear cells treated with methotrexate and dexamethasone.
P-glycoprotein (P-gp), a product of the MDR1 gene, is an important factor in the turnover of many drugs and xenobiotics. Recent reports have suggested that P-gp can also be involved in the transport of cytokines. The aim of this study was to examine the role of P-gp in cytokine release from phytohaemagglutinin (PHA)-stimulated peripheral blood mononuclear cells (MNCs) as well as in the release of cytokines from MNCs treated with methotrexate (MTX) and dexamethasone (DEX). The study was carried out on PHA-stimulated MNC from 10 healthy subjects. Flow cytometry was applied to measure interleukin (IL)-2, IL-4, IL-6, IL-10, interferon (IFN)-gamma and tumour necrosis factor (TNF)-alpha levels in the culture supernatants. In the experiments verapamil (VER) and P-gp specific monoclonal antibodies (mAb) (clone 17F9) were used to inhibit P-gp function. P-gp inhibitors suppressed the release of IL-2, IL-4, IFN-gamma and TNF-alpha from PHA-stimulated MNC, whereas release of IL-6 and IL-10 remained unaffected. VER and mAb significantly decreased the release of IL-2, IL-4, TNF-alpha and INF-gamma in MNC cultures treated with MTX or DEX. The results of this study suggest that P-gp may be involved in the transmembrane transport of some cytokines. Moreover, it seems that blocking of P-gp function may influence the release of some cytokines from MNCs, displaying an additive inhibitory effect to DEX and MTX.
Pawlik
A
A
Department of Pharmacokinetics and Therapeutic Drug Monitoring, Pomeranian Medical University, al. Powstańców Wlkp. 72, 70-111 Szczecin, Poland. pawand@poczta.onet.pl
Baśkiewicz-Masiuk
M
M
Machaliński
B
B
Safranow
K
K
Gawrońska-Szklarz
B
B
D020168:ATP Binding Cassette Transporter, Subfamily B, Member 1 / Q000037:antagonists & inhibitors / Q000276:immunology / Q000494:pharmacology*; D000893:Anti-Inflammatory Agents; D000911:Antibodies, Monoclonal; D002478:Cells, Cultured; D016207:Cytokines / Q000378:metabolism*; D003907:Dexamethasone; D004305:Dose-Response Relationship, Drug; D006801:Humans; D007371:Interferon-gamma / Q000378:metabolism; D007378:Interleukins / Q000378:metabolism; D007963:Leukocytes, Mononuclear / Q000187:drug effects / Q000378:metabolism*; D008727:Methotrexate; D010835:Phytohemagglutinins; D014409:Tumor Necrosis Factor-alpha / Q000378:metabolism; D014700:Verapamil / Q000494:pharmacology
D020168:ATP Binding Cassette Transporter, Subfamily B, Member 1; D000893:Anti-Inflammatory Agents; D000911:Antibodies, Monoclonal; D016207:Cytokines; D007378:Interleukins; D010835:Phytohemagglutinins; D014409:Tumor Necrosis Factor-alpha; D003907:Dexamethasone; D007371:Interferon-gamma; D014700:Verapamil; D008727:Methotrexate