TRAIL, DR4 and DR5 are upregulated in kidneys from patients with lupus nephritis and exert proliferative and proinflammatory effects.
We have previously reported that TRAIL is upregulated on T cells from patients with lupus and that T cell associated TRAIL enhances autoimmune parameters in a murine model of lupus. Whether TRAIL/TRAIL-R interaction plays a role in organ involvement such as lupus nephritis has not yet been assessed. We demonstrate here that TRAIL, DR4 and DR5 are upregulated in proximal and distal tubules of patients with proliferative lupus nephritis. In vitro, expression of TRAIL, DR4 and DR5 on primary proximal tubular epithelial cells (PTEC) was induced by TNFalpha and IFNgamma. Functionally, TRAIL did not induce apoptosis but rather enhanced the proliferation of PTEC through activation of PI3 kinase/AKT and ERK1/2, increased IL-8 production and upregulated ICAM-1 expression. These data demonstrate that cytokine induced upregulation of TRAIL, DR4 and DR5 in tubules from patients with proliferative lupus nephritis may play a protective role by enhancing PTEC survival while also exerting a proinflammatory effect that may contribute to local inflammation and injury.
Division of Rheumatology and Clinical Immunology, Department of Medicine, University of Maryland School of Medicine, Baltimore, MD 21201, USA.
Vinh
V
Nguyen
Cornelia
C
Cudrici
Valentina
V
Zernetkina
Florin
F
Niculescu
Horea
H
Rus
Cynthia
C
Drachenberg
Violeta
V
Rus
D000293:Adolescent; D000328:Adult; D017209:Apoptosis; D015153:Blotting, Western; D049109:Cell Proliferation; D002470:Cell Survival; D002478:Cells, Cultured; D004797:Enzyme-Linked Immunosorbent Assay; D004847:Epithelial Cells / Q000166:cytology / Q000378:metabolism; D005260:Female; D005434:Flow Cytometry; D006801:Humans; D007150:Immunohistochemistry; D018836:Inflammation Mediators / Q000378:metabolism; D007371:Interferon-gamma / Q000494:pharmacology; D007668:Kidney / Q000378:metabolism* / Q000473:pathology; D007687:Kidney Tubules, Proximal / Q000166:cytology / Q000378:metabolism; D008181:Lupus Nephritis / Q000378:metabolism* / Q000473:pathology; D008297:Male; D008875:Middle Aged; D053220:Receptors, TNF-Related Apoptosis-Inducing Ligand / Q000378:metabolism*; D018124:Receptors, Tumor Necrosis Factor / Q000378:metabolism*; D053221:TNF-Related Apoptosis-Inducing Ligand / Q000378:metabolism*; D014409:Tumor Necrosis Factor-alpha / Q000494:pharmacology; D055815:Young Adult
D018836:Inflammation Mediators; D053220:Receptors, TNF-Related Apoptosis-Inducing Ligand; D018124:Receptors, Tumor Necrosis Factor; D053221:TNF-Related Apoptosis-Inducing Ligand; C105190:TNFRSF10A protein, human; C505653:TNFSF10 protein, human; D014409:Tumor Necrosis Factor-alpha; D007371:Interferon-gamma