Increased responsiveness to toll-like receptor 4 stimulation in peripheral blood mononuclear cells from patients with recent onset rheumatoid arthritis.
BACKGROUND
Cell signaling via Toll-like receptors (TLRs) leads to synovial inflammation in rheumatoid arthritis (RA). We aimed to assess effects of TLR2 and TLR4 stimulation on proinflammatory cytokine production by peripheral blood mononuclear cells (PBMCs) from patients with recent-onset RA, osteoarthrosis (OA), and healthy control (HC).


METHODS
PBMCs were stimulated with LPS, biglycan and cytokine mix. Cytokines were analyzed in supernatants with ELISA. Expression of toll-like receptors mRNA in leukocytes was analyzed using real-time qPCR.


RESULTS
PBMCs from RA patients spontaneously produced less IL-6 and TNFalpha than cells from OA and HC subjects. LPS increased cytokines' production in all groups. In RA patients increase was dramatic (30 to 48-fold and 17 to 31-fold, for respective cytokines) compared to moderate (2 to 8-fold) in other groups. LPS induced 15-HETE generation in PBMCs from RA (mean 251%) and OA patients (mean 43%), although only in OA group, the increase was significant. TLR2 and TLR4 gene expressions decreased in response to cytokine mix, while LPS enhanced TLR2 expression in HC and depressed TLR4 expression in OA patients.


CONCLUSIONS
PBMCs from recent-onset RA patients are overresponsive to stimulation with bacterial lipopolysaccharide. TLR expression is differentially regulated in healthy and arthritic subjects.
Kowalski
M L
ML
Department of Immunology, Rheumatology and Allergy, Chair of Immunology, Medical University of Lodz, Pomorska 251, 92-213 Lodz, Poland. marek.kowalski@csk.umed.lodz.pl
Wolska
A
A
Grzegorczyk
J
J
Hilt
J
J
Jarzebska
M
M
Drobniewski
M
M
Synder
M
M
Kurowski
M
M
D000328:Adult; D000368:Aged; D001172:Arthritis, Rheumatoid / Q000097:blood*; D058578:Biglycan; D002478:Cells, Cultured; D017077:Culture Media, Conditioned / Q000378:metabolism; D004797:Enzyme-Linked Immunosorbent Assay; D016326:Extracellular Matrix Proteins / Q000494:pharmacology; D005260:Female; D015870:Gene Expression / Q000187:drug effects; D006801:Humans; D015850:Interleukin-6 / Q000378:metabolism / Q000494:pharmacology; D007963:Leukocytes, Mononuclear / Q000166:cytology / Q000187:drug effects / Q000378:metabolism*; D008070:Lipopolysaccharides / Q000494:pharmacology; D008297:Male; D008875:Middle Aged; D010003:Osteoarthritis / Q000097:blood; D011509:Proteoglycans / Q000494:pharmacology; D012333:RNA, Messenger / Q000235:genetics / Q000378:metabolism; D020133:Reverse Transcriptase Polymerase Chain Reaction; D051195:Toll-Like Receptor 2 / Q000235:genetics / Q000378:metabolism; D051197:Toll-Like Receptor 4 / Q000235:genetics* / Q000378:metabolism; D014409:Tumor Necrosis Factor-alpha / Q000378:metabolism / Q000494:pharmacology
C546884:BGN protein, human; D058578:Biglycan; D017077:Culture Media, Conditioned; D016326:Extracellular Matrix Proteins; D015850:Interleukin-6; D008070:Lipopolysaccharides; D011509:Proteoglycans; D012333:RNA, Messenger; C495345:TLR4 protein, human; D051195:Toll-Like Receptor 2; D051197:Toll-Like Receptor 4; D014409:Tumor Necrosis Factor-alpha