A comparative study of interleukin-1beta production and p2x7 expression after ATP stimulation by peripheral blood mononuclear cells isolated from rheumatoid arthritis patients and normal healthy controls.
Interleukin 1 beta (IL-1beta) is a proinflammatory cytokine that is considered to play an important role in the progression of rheumatoid arthritis (RA). A stimulus such as ATP is necessary to cause the release of mature IL-1beta, via activation of the P2X(7) receptor on monocytes. In this study, the production of IL-1beta in whole blood after ATP stimulation and expression of P2X(7) receptors in RA and healthy subjects were examined. Blood samples from RA patients or healthy controls were stimulated with ATP in the presence of lipopolysaccharide (LPS). Supernatants were harvested and IL-1beta levels were measured by enzyme-linked immunosorbent assay (ELISA). Expression of P2X(7) receptors was measured using flow cytometry. ATP induced significantly higher levels of IL-1beta in LPS-activated RA blood samples compared to controls. A significant up-regulation of P2X(7) receptor expression on mononuclear cells was observed after overnight incubation with ATP without any significant differences between RA patients and normals. These data suggest that RA patient mononuclear cells are more sensitive to ATP stimulation than healthy individuals perhaps due to genetic polymorphism in the P2X(7) gene.
Al-Shukaili
Ahmed
A
Department of Microbiology and Immunology, College of Medicine and Health Sciences, Sultan Qaboos University, P.O. Box 35, PC 123, Muscat, Sultanate of Oman. shukaily@squ.edu.om
Al-Kaabi
Juma
J
Hassan
Batool
B
D000255:Adenosine Triphosphate / Q000378:metabolism*; D000328:Adult; D001172:Arthritis, Rheumatoid / Q000276:immunology / Q000378:metabolism*; D016022:Case-Control Studies; D002478:Cells, Cultured; D004797:Enzyme-Linked Immunosorbent Assay; D005260:Female; D005434:Flow Cytometry; D006801:Humans; D053583:Interleukin-1beta / Q000097:blood / Q000378:metabolism*; D007963:Leukocytes, Mononuclear / Q000187:drug effects / Q000276:immunology / Q000378:metabolism*; D018950:Lipopolysaccharide Receptors / Q000032:analysis; D008070:Lipopolysaccharides / Q000494:pharmacology; D008297:Male; D008875:Middle Aged; D018048:Receptors, Purinergic P2 / Q000378:metabolism*; D058486:Receptors, Purinergic P2X7; D013997:Time Factors
D053583:Interleukin-1beta; D018950:Lipopolysaccharide Receptors; D008070:Lipopolysaccharides; C546468:P2RX7 protein, human; D018048:Receptors, Purinergic P2; D058486:Receptors, Purinergic P2X7; C482199:lipopolysaccharide, E coli O55-B5; D000255:Adenosine Triphosphate