Infliximab regulates monocytes and regulatory T cells in Kawasaki disease.

BACKGROUND: The effect of infliximab (IFX) on immune cells has not been fully reported in Kawasaki disease (KD). To investigate the mechanism of IFX in KD, we examined changes in the abundance of CD14+ CD16+ activated monocytes, regulatory T cells (Treg ) cells, and T-helper type 17 (Th17) cells following treatment with IFX. METHODS: We collected peripheral blood from patients with i.v. immunoglobulin (IVIG)-resistant KD and analyzed absolute CD14+ CD16+ monocyte, Treg (CD4+ CD25+ FOXP3+ ) and Th17 cell (CD4+ IL-17A+ ) counts on flow cytometry. We also measured changes in serum soluble interleukin (IL)-2 receptor (IL-2R), IL-6, and tumor necrosis factor (TNF)-α on enzyme-linked immunosorbent assay. RESULTS: Treg cells and Th17 cells significantly increased after IFX treatment compared with baseline (126 ± 85 cells/µL vs 62 ± 53 cells/µL, P < 0.01; 100 ± 111 cells/µL vs 28 ± 27 cells/µL, P < 0.05, respectively). In contrast, in a subgroup of patients with CD14+ CD16+ monocytes above the normal range before IFX, the CD14+ CD16+ monocytes significantly decreased following IFX treatment (72 ± 51 cells/µL vs 242 ± 156 cells/µL, P < 0.05).. Serum TNF-α did not change, but soluble IL-2R and IL-6 decreased after IFX treatment. CONCLUSION: IFX could downregulate activated monocytes and upregulate Treg cells towards the normal range. IFX treatment thus contributes to the process of attenuating inflammation in KD.

Plasma Exchange Downregulates Activated Monocytes and Restores Regulatory T Cells in Kawasaki Disease.

In Kawasaki disease (KD), the effect of plasma exchange (PE) on immune cells has not been fully elucidated. Therefore, we examined the changes in the number of CD14+ CD16+ activated monocytes, regulatory T (Treg ), and T-helper type 17 (Th17) cells in KD patients treated with PE. The percentage of total monocytes and subclasses of lymphocytes, including CD4+ and CD8+ T cells, and CD19+ B cells, showed no significant difference before and after PE. However, the percentage of CD14+ CD16+ monocytes in total leukocytes decreased significantly after PE (1.1% ± 1.5% vs. 2.1% ± 2.3%, P < 0.05). Furthermore, while the percentage of Th17 cells in CD4+ T cells did not change, the percentage of Treg cells in CD4+ T cells increased significantly after PE (11.1% ± 5.1% vs. 8.0% ± 4.4%, P < 0.05). Therefore, PE downregulates activated monocytes and upregulates Treg cells toward normal levels and thus attenuates inflammation in KD.

Local level of TGF-ß1 determines the effectiveness of dexamethasone through regulating the balance of Treg/Th17 cells in TNBS-induced mouse colitis.

Transforming growth factor ß1 (TGF-ß1) has a crucial role in regulating the balance of type 17 T-helper cells (Th17) and T regulatory cells (Tregs) that are involved in the pathogenesis of inflammatory bowel disease, while the function of local TGF-ß1 in this process has remained to be fully elucidated. The present study investigated the effects of different local TGF-ß1 levels on the Treg/Th17 balance and on the dexamethasone efficacy in mice with 2,4,6-trinitrobenzenesulfonic acid (TNBS)-induced colitis. Various TGF-ß1 levels in colon tissue were achieved by enema delivery of a high, medium or low amount of adenovirus expressing TGF-ß1 (107, 108 or 109 pfu, denoted as AdTGF-1, AdTGF-2 and AdTGF-3, respectively). Dexamethasone further decreased colon damage and myeloperoxidase activity in TNBS mice receiving AdTGF-1 and AdTGF-2. When AdTGF-1 was administered, dexamethasone enhanced its effect by reducing interferon (IFN)-γ and increasing interleukin (IL)-10 production. In TNBS mice receiving AdTGF-2, the increase in IFN-γ, tumor necrosis factor-α, IL-6, IL-17 and IL-23 was significantly prevented by dexamethasone treatment. In comparison with the lower doses, AdTGF-3 exerted the opposite effect on regulating the cytokine production in TNBS mice, which was not affected by dexamethasone treatment. In mesenteric lymph nodes, AdTGF-1 prevented the TNBS-induced reduction of Tregs and IL-10, and potentially increased the efficacy of dexamethasone. In addition, dexamethasone further decreased the levels of activated caspase3 in TNBS mice receiving adenoviral TGF-ß1, particularly in the AdTGF-1 group. The activation of the p38 mitogen-activated protein kinase/c-Jun N-terminal kinase/c-Jun pathway was significantly inhibited by a low amount of TGF-ß1 administered to TNBS-treated mice, which was further decreased by dexamethasone. The present study provided evidence that the therapeutic effect of dexamethasone may depend on the local levels of TGF-ß1 in TNBS-induced colitis and may be mediated, at least partially, through promoting the differentiation of Tregs and thus altering the balance of pro- and anti-inflammatory cytokines.

Early Changes in Circulatory T Helper Type 1, 2, and 17 Cells of Patients with Out-of-Hospital Cardiac Arrest after Successful Cardiopulmonary Resuscitation.

BACKGROUND: Immune disorder is an important feature of patients with out-of-hospital cardiac arrest (OHCA) after the return of spontaneous circulation (ROSC). We investigated the expression of circulatory T helper type (Th) 1, Th2, and Th17 cells to explore the early immune alteration in OHCA patients after ROSC. METHODS: During July-September 2016 and March-September 2017, 65 consecutive OHCA patients with ROSC >12 h and 30 healthy individuals were enrolled in this study. Clinical and 28-day survival data were collected. Peripheral blood samples were analyzed to evaluate the expression of Th1/Th2/Th17 cells by flow cytometry from OHCA patients after ROSC on days 1 and 3 and from healthy individuals. RESULTS: Compared with healthy individuals, T lymphocyte counts and Th1 cell counts decreased on days 1 and 3 after ROSC (1464 [1198, 2152] vs. 779 [481, 1140] vs. 581 [324, 1118]/µl, χ2 = 30.342, P < 0.001; 154 [90, 246] vs. 39 [19, 78] vs. 24 [12, 53]/µl, χ2 = 42.880, P < 0.001), and Th2 and Th17 cell counts decreased on day 3 (17.0 [10.8, 24.0] vs. 9.0 [3.0, 15.5]/µl, Z = -3.228, P = 0.001; 4.7 [2.7, 9.1] vs. 2.7 [1.0, 6.5]/µl, Z = -2.294, P = 0.022). No change in CD4+/CD3+ lymphocyte ratio was seen on day 1 or day 3 (57.9 [49.4, 63.0] vs. 55.4 [46.5, 66.5] vs. 55.4 [50.2, 67.0]%, χ2 = 0.171, P = 0.918). Th1/CD4+ lymphocyte ratio decreased on days 1 and 3 (19.0 [14.0, 24.9] vs. 9.3 [4.6, 13.9] vs. 9.5 [4.9, 13.6]%, χ2 = 25.754, P < 0.001), and Th2/CD4+ lymphocyte ratio increased on day 1 and decreased on day 3 (1.9 [1.2, 2.5] vs. 2.5 [1.6, 4.0] vs. 1.9 [1.6, 3.8]%, χ2 = 6.913, P = 0.032). Th1/Th2 cell ratio also decreased on both days (9.4 [7.3, 13.5] vs. 3.1 [1.9, 5.6] vs. 4.2 [2.8, 5.9], χ2 = 44.262, P < 0.001). Despite an upward trend in the median of Th17/CD4+ lymphocyte ratio in OHCA patients, there was no significant difference compared with healthy individuals (0.9 [0.4, 1.2] vs. 0.7 [0.4, 1.2] vs. 0.6 [0.3, 1.0]%, χ2 = 2.620, P = 0.270). The dynamic expression of Th1/Th2/Th17 cells on days 1 and 3 were simultaneously analyzed in 28/53 OHCA patients who survived >3 days; patients were divided into survivors (n = 10) and nonsurvivors (n = 18) based on 28-day survival. No significant differences in Th1/Th2/Th17 cell counts, ratios in CD4+ lymphocytes, and Th1/Th2 cell ratio were seen between survivors and nonsurvivors on both days (all P > 0.05). There was no difference over time in both survivors and nonsurvivors (all P > 0.05). CONCLUSION: Downregulated T lymphocyte counts, including Th1/Th2/Th17 subsets and Th1/Th2 cell ratio imbalance, occur in the early period after ROSC, that may be involved in immune dysfunction in OHCA patients.