Ankylosing spondylitis (AS) is a chronic inflammatory rheumatic disease strongly associated with HLA-B*27, an major histocompatibility complex (MHC) molecule that presents peptide antigen to T cells. Previously, regulatory B cells were found to suppress T cell-mediated autoimmunity induction and chronic inflammation, partially through interleukin (IL)-10 production. Here, we examined the role of regulatory B cells in AS pathogenesis. Apheresis samples from HLA-B*27-positive AS patients and non-AS healthy controls were collected. We found that although AS patients and non-AS controls presented similar frequencies of CD24(+)CD38(+) B cells, compared to non-AS controls, those from AS patients produced less IL-10 under ex vivo condition and after CD40 and B-cell receptor (BCR) stimulation. Purified T cell-B cell cocultures showed that compared to non-AS controls, CD24(+)CD38(+) B cells from AS patients were defective at suppressing naive and memory CD8(+) T cell activation. The suppression of memory CD8(+) T cells in non-AS controls appeared to be mediated by IL-10, since the addition of IL-10 mAb suppressed CD24(+)CD38(+) B cell-mediated downregulation of proinflammatory cytokine production and proliferation. To rescue the defect in AS patients, CD24(+)CD38(+) B cells were pretreated by CD40 and BCR stimulation, which enhanced CD24(+)CD38(+) B cell-mediated memory CD8(+) T cell suppression. Together, our data discovered a regulatory B cell defect in AS patients.
Rheumatoid arthritis (RA) is characterized by a chronic inflammatory process that targets the synovial lining of diarthrodial joints. TIM-3 plays a key role in the negative regulation of the immune response. In this study, we investigated the expression of TIM-3 on CD4+ and CD8+ T cells from systemic (peripheral blood) and local (synovial fluid) perspectives of RA. Level of TIM-3+ cells from peripheral blood and synovial fluid of patients as well as peripheral blood of healthy controls was measured by flow cytometry. Results showed that TIM-3 expression was significantly increased in both CD4+ and CD8+ T cells in the peripheral blood of RA (p < 0.001 and p < 0.001, respectively). Furthermore, patients revealed even higher expression of TIM-3 in CD4+ and CD8+ T cells in synovial fluid than in peripheral blood. When comparing TIM-3 level with the severity of RA, we identified that the percentage of TIM-3 on both peripheral CD4+ and peripheral CD8+ T cells was negatively correlated with disease activity score 28 (DAS28) of the patients. Similarly, TIM-3 on synovial fluid CD4+ and CD8+ T cells also revealed inverse correlation with DAS28 of the cases. Our data demonstrate a negative correlation between TIM-3 and the disease progression of RA.
A series of novel
N
-alkyl-1-deoxynojirimycin derivatives
25 ∼ 44
were synthesised and evaluated for their in vitro α-glucosidase inhibitory activity to develop α-glucosidase inhibitors with high activity. All twenty compounds exhibited α-glucosidase inhibitory activity with IC
50
values ranging from 30.0 ± 0.6 µM to 2000 µM as compared to standard acarbose (IC
50
= 822.0 ± 1.5 µM). The most active compound
43
was ∼27-fold more active than acarbose. Kinetic study revealed that compounds
43
,
40
, and
34
were all competitive inhibitors on α-glucosidase with
K
i
of 10 µM, 52 µM, and 150 µM, respectively. Molecular docking demonstrated that the high active inhibitors interacted with α-glucosidase by four types of interactions, including hydrogen bonds, π–π stacking interactions, hydrophobic interactions, and electrostatic interaction. Among all the interactions, the π–π stacking interaction and hydrogen bond played a significant role in a various range of activities of the compounds.
Chlorogenic acid and its derivatives (CADs) are valuable bioactive plant secondary metabolites with many health benefits. In the present study, Stevia rebaudiana hairy root cultures were established, and the culture conditions for the production of CADs were optimized. The hairy roots were induced by coculture of S. rebaudiana leaves and Agrobacterium rhizogenes (C58C1) after infection, which were further verified by PCR detection of rolB and rolC genes. HPLC-MS and HPLC analysis showed that chlorogenic acid (3-caffeoylquinic acid, 3-CQA), 3,5-dicaffeoylquinic acid (3,5-CQA), and 4,5-dicaffeoylquinic acid (4,5-CQA) were the major CADs in the hairy roots. Eight single roots with rapid growth rate were selected. Among them, T3 had the highest yield of CADs. B5 medium supplemented with 40 g/L sucrose was more suitable for the production of CADs than others. Under optimal culture conditions, the total content of these three compounds reached 105.58 mg/g and total yield was 234.40 mg/100 mL.
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