In situ hybridization analysis of synovial and systemic cytokine messenger RNA expression in superantigen-mediated Staphylococcus aureus arthritis.
OBJECTIVE
To investigate patterns of synovial and systemic cytokine messenger RNA (mRNA) expression in mice with superantigen-mediated Staphylococcus aureus arthritis.


METHODS
Mice were inoculated intravenously with 1 x 10(7) colony-forming units of toxic shock syndrome toxin-1-producing S aureus LS-1. Synovial tissues and spleens were obtained at varying time intervals after bacterial inoculation, and examined for mRNA expression of interleukin-1beta (IL-1beta), IL-4, IL-10, IL-12, tumor necrosis factor alpha (TNFalpha), TNFbeta, interferon-gamma (IFN-gamma), transforming growth factor beta, and perforin, by an in situ hybridization technique.


RESULTS
In situ hybridization revealed early synovial up-regulation of TNFalpha and IL-1 beta mRNA expression. Peak frequencies of these proinflammatory cytokines were observed at the second and third week of the infection. Expression of T cell-derived cytokine mRNAs was detected later, and in a relatively low frequency. Notably, induction and peak numbers of Th2 cytokine (IL-4 and IL-10) mRNA expression preceded Th1 cytokine (IFNgamma and TNFbeta) mRNAs. In comparison with synovial tissues, peak spleen cytokine mRNA expression of IL-1beta, TNFalpha, TNFbeta, IL-12, and IFNgamma occurred earlier, but displayed a clearly lower magnitude of expression.


CONCLUSIONS
These findings demonstrate synovial and systemic up-regulation of cytokine mRNA expression during S aureus arthritis, indicating that both monocyte/macrophage and T cell-derived products are involved in the pathogenesis of this disease.
Zhao
Y X
YX
University of Göteborg, Sweden.
Ljungdahl
A
A
Olsson
T
T
Tarkowski
A
A
D000818:Animals; D001170:Arthritis, Infectious / Q000209:etiology / Q000378:metabolism*; D001427:Bacterial Toxins; D016207:Cytokines / Q000378:metabolism*; D004195:Disease Models, Animal; D004768:Enterotoxins; D005260:Female; D017403:In Situ Hybridization; D007378:Interleukins / Q000378:metabolism; D008297:Male; D051379:Mice; D008969:Molecular Sequence Data; D012333:RNA, Messenger / Q000378:metabolism*; D013154:Spleen / Q000378:metabolism*; D013203:Staphylococcal Infections / Q000209:etiology / Q000378:metabolism*; D018089:Superantigens; D013583:Synovial Membrane / Q000378:metabolism*; D014409:Tumor Necrosis Factor-alpha / Q000378:metabolism
D001427:Bacterial Toxins; D016207:Cytokines; D004768:Enterotoxins; D007378:Interleukins; D012333:RNA, Messenger; D018089:Superantigens; D014409:Tumor Necrosis Factor-alpha; C030107:enterotoxin F, Staphylococcal