Abstract Background: Adaptive immune cells, including CD4+CD69+ and CD4+CD25+FoxP3+ regulatory T (Treg) cells, are important for maintaining immunological tolerance. In human systemic lupus erythematosus (SLE), CD4+CD25+FoxP3+ Treg cells are reduced, whereas CD69 expression is increased, resulting in a homeostatic immune imbalance that may intensify autoreactive T cell activity. To analyze the mechanisms implicated in autotolerance failure, we evaluated CD4+CD69+ and CD4+CD25+FoxP3+ T cells and interleukin profiles in a pristane-induced SLE experimental model. Methods: For lupus induction, 26 female Balb/c mice received a single intraperitoneal 0.5 ml dose of pristane, and 16 mice received the same dose of saline. Blood and spleen samples were collected from euthanized mice 90 and 120 days after pristane or saline inoculation. Mononuclear cells from peripheral blood (PBMC), peritoneal lavage (PL) and splenocytes were obtained by erythrocyte lysis and cryopreserved for further evaluation by flow cytometry using the GuavaEasyCyte TM HT. After thawing, cells were washed and stained with monoclonal antibodies against CD3, CD4, CD8, CD25, CD28, CD69, FoxP3, CD14 and Ly6C (BD Pharmingen TM). Interleukins were quantified using Multiplex® MAP. The Mann-Whitney test and the Pearson coefficient were used for statistical analysis, and p < 0.05 considered significant. Results: Compared with the controls, SLE-induced animals presented increased numbers of CD4+CD69+ T cells in the blood on T90 and T120 (p = 0.022 and p = 0.008) and in the spleen on T120 (p = 0.049), but there were decreased numbers in the PL (p = 0.049) on T120. The percentage of Treg was lower in blood (p < 0.005 and p < 0.012) on T90 and T120, in spleen (p = 0.043) on T120 and in PL (p = 0.001) on T90. Increased numbers of CD4+ CD69+ T cells in the PL were positively associated with high IL-2 (p = 0.486) and IFN-γ (p = 0.017) levels, whereas reduced Treg cells in the blood were negatively correlated with TNFα levels (p = 0.043) and positively correlated with TGFβ1 (p = 0.038). Conclusion: Increased numbers of CD4+CD69+ T cells and reduced numbers of CD4+CD25+FoxP3+ Treg cells with an altered interleukin profile suggests loss of autotolerance in pristane-induced lupus mice, which is similar to human lupus. Therefore, this model is useful in evaluating mechanisms of cellular activation, peripheral tolerance and homeostatic immune imbalance involved in human SLE.

OBJECTIVES: To analyse the frequency of metabolic syndrome in young adult female dermatomyositis patients and its possible association with clinical and laboratory dermatomyositis-related features and serum adipocytokines. METHOD: This cross-sectional study included 35 dermatomyositis patients and 48 healthy controls. Metabolic syndrome was defined according to the 2009 Joint Interim Statement. RESULTS: Patient age was comparable in the dermatomyositis and control groups, and the median disease duration was 1.0 year. An increased prevalence of metabolic syndrome was detected in the dermatomyositis group (34.3% vs. 6.3%; p=0.001). In addition, increased serum adiponectin and resistin levels were noted in contrast to lower leptin levels. In dermatomyositis patients, adipocytokine levels were correlated with the levels of total cholesterol, low-density cholesterol, triglycerides and muscle enzymes. A comparison of dermatomyositis patients with (n=12) and without (n=23) syndrome metabolic revealed that adipocytokine levels were also correlated with age, and that dermatomyositis patients with metabolic syndrome tended to have more disease activity despite similar adipocytokine levels. CONCLUSIONS: Metabolic syndrome is highly prevalent in young adult female dermatomyositis patients and is related to age and disease activity. Moreover, increased serum adiponectin and resistin levels were detected in dermatomyositis patients, but lower serum leptin levels were observed.

OBJECTIVE: To evaluate the effect of low dose methotrexate alone or in combination with glucocorticoid treatment on titanium implant osseointegration. METHODS: Groups of 6-8 adult New Zealand White rabbits were treated for 18 weeks with saline (control), methotrexate, glucocorticoid, or methotrexate plus glucocorticoid. The animals received a titanium implant in the tibia at week 6. Lumbar spine and tibia bone mineral densities were analyzed before and after treatment. Histomorphometric analysis of bone cortical thickness, total bone area around the implant, and % of bone to implant contact was performed. RESULTS: After 18 weeks, the change in the bone mineral density in the lumbar spines and tibias in the methotrexate group was comparable to the control group (0.035 vs. 0.055 g/cm² and 0.021 vs. 0.041 g/cm², respectively). In contrast, both the glucocorticoid group and glucocorticoid plus methotrexate group had significant reductions at both sites. Histomorphometric analysis of the tibia in the control and methotrexate groups revealed no significant changes in cortical thickness (133 vs. 126 μm), total bone area around the implant (33 vs. 30%), or bone to implant contact (40 vs. 38%). In contrast, glucocorticoid group had significant reductions compared to controls in tibia cortical thickness (99 vs. 133 μm), total bone area around the implant (24 vs. 33%), and bone to implant contact (27 vs. 40%). Similar reductions were observed in the glucocorticoid plus methotrexate group. CONCLUSIONS: Our results demonstrate that low dose methotrexate treatment does not affect titanium implant osseointegration, suggesting that this therapy is safe for surgical procedures requiring a titanium implant.