Jun-hwan Kim

Altered frequency and migration capacity of CD4+CD25+ regulatory T cells in systemic lupus erythematosus

OBJECTIVES To determine the frequency and chemokine receptor-related migratory capacity of CD4(+)CD25(+) regulatory T cells (Tregs) and their association with clinical parameters in patients with SLE. METHODS The expression of CD4, CD25, FoxP3 and CCR4 was examined with flow cytometry after staining with fluorescence-conjugated antibodies in 20 patients with SLE, 20 patients with RA and 21 age- and sex-matched healthy controls. For analysis of migration capacity in 24-well chemotaxis chambers, sorted cells were stimulated with ligands of CCR4, CCL17 and CCL22 and analysed with FACScan. Correlations between the number of Tregs and CCR4(+) Treg cells and clinical parameters were analysed. RESULTS The numbers of Tregs(bright) and CCR4(+) Tregs(bright) were significantly decreased in the patients with SLE compared with healthy controls. The number of Tregs(bright) was negatively correlated with the levels of anti-dsDNA antibody and the number of CCR4(+) Tregs(bright) had a positive correlation with the levels of C(3). Percentage of migrated Tregs(bright) by CCL17 or CCL22 was significantly decreased in the patients with SLE compared with healthy controls. CONCLUSIONS These results suggest that altered frequency of Tregs and CCR4(+) Tregs(bright) and decreased migratory capacity of Tregs might be involved in the pathogenesis of SLE and indicate that targeting the Tregs can be a new therapeutic strategy in SLE.

Kinetics of IL-6 and TNF-α changes in a canine model of sepsis induced by endotoxin.

Sepsis is a major cause of death in veterinary medicine, although a better prognosis can result from an early diagnosis. To speed the diagnosis, the biomarkers TNF-α and IL-6 can provide valuable information regarding systemic inflammatory response. The purpose of this study was to investigate the changes in cytokine levels in an experimental model of sepsis using ELISA and real-time PCR. Ten adult Beagles were studied; seven received an IV bolus of high dose lipopolysaccharide solution (1mg/kg) to induce sepsis. The remaining three beagles were the control group. Blood samples were collected before and 1, 3, 6, 12, 24 and 48 h after administering LPS. Serum IL-6 level peaked at 3h (1.89 ± 0.10 ng/ml) and serum TNF-α peaked at 1h (1.11 ± 0.01 ng/ml). The expression of IL-6 mRNA in peripheral blood mononuclear cells (PBMC) increased 62-fold compared to the control group at 1h; TNF-α mRNA increased by 4.5-fold at 1h. The expressions of IL-6 and TNF-α mRNA in PBMCs changed more rapidly than serum IL-6 and TNF-α concentrations. In addition, TNF-α mRNA levels in PBMCs remained elevated longer than serum TNF-α. Our study establishes the basis for future work aimed at a better understanding of the systemic inflammatory response to infection and sepsis in canine patients.

Serial Changes of CD4+CD25+FoxP3+ Regulatory T Cell in Canine Model of Sepsis Induced by Endotoxin

ABSTRACT Regulatory T cells (Tregs) suppress the immune system and maintain the homeostasis of the immune system in healthy dogs. In septic patients, the percentage of circulating Tregs is increasing, which may cause the sepsis-induced immunosuppression. This study was performed to investigate the changes of the percentage of Tregs in total lymphocytes of the peripheral blood in the experimental canine endotoxemia model. The animals injected with a high dose lipopolysaccharide (LPS) induced severe leukopenia followed by leukocytosis, but the total lymphocytes number was relatively consistent. As a result of flow cytometric analysis, the percentage of Tregs in total lymphocytes of the peripheral blood was 8.45 ± 1.30% (day 0), and it temporarily decreased 2.54 ± 1.16% (day 1) and increased continuously until the end of the experiment (14.34 ± 4.10% on day 3 and 25.70 ± 7.39% on day 7), respectively. This study provides basic information in physiologic and immunologic changes in Tregs in dogs with sepsis model.