Role of Regulatory B Cells in the Progression of Cervical Cancer.

This study is to investigate the role of regulatory B (Breg) cells in cervical cancer. In total, 70 cases of cervical cancer, 52 cases of cervical intraepithelial neoplasia (CIN), and 40 normal controls were enrolled. The percentage of Breg cells was detected by flow cytometry. Serum levels of IL-10 were measured by ELISA. The correlation between Breg cells and the clinical characterizations of cervical cancer was analyzed. The inhibition effect of Breg cells on CD8+ T cells was tested by blocking IL-10 in vitro. The percentage of CD19+CD5+CD1d+ Breg cells and the level of IL-10 of patients with cervical cancer or CIN were significantly higher than those in the control group (P < 0.05). And the postoperative levels of Breg cells and IL-10 were significantly lower than the preoperative levels (P < 0.05). Breg cells and the IL-10 level were positively correlated in cervical cancer patients (r = 0.516). In addition, the Breg cell percentage was closely related to the FIGO stages, lymph node metastasis, tumor differentiation, HPV infection, and the tumor metastasis of cervical cancer (P < 0.05). The Breg cell percentage was negatively correlated with CD8+ T cells of cervical cancer patients (r = -0.669). The level of IL-10 in the culture supernatant of Bregs treated with CpG was significantly higher than that of non-Bregs (P < 0.05). After coculture with Bregs, the quantity of CD8+ T cells to secrete perforin and Granzyme B was significantly decreased, and this effect was reversed after blocking IL-10 by a specific antibody. Breg cells are elevated in cervical cancer and associated with disease progression and metastasis. Moreover, they can inhibit the cytotoxicity of CD8+ T cells.

Increased Circulating Th17 but Decreased CD4+Foxp3+ Treg and CD19+CD1dhiCD5+ Breg Subsets in New-Onset Graves' Disease.

Th17 and regulatory lymphocyte subsets such as Tregs and Bregs have been reported to play important roles in autoimmune diseases. The aim of this work was to perform quantitative studies of circulating Th17, Tregs, and Bregs in patients with new-onset Graves' disease (GD). Twenty GD patients and 20 healthy controls were involved in this study. Blood samples were taken for flow cytometry detection of CD4+IL-17+ Th17, CD4+Foxp3+ Tregs, and CD19+CD1dhiCD5+ Bregs and meanwhile, for real-time PCR measurement of gene expressions of RORγt, IL-17 and IL-10. The proportions of Tregs and Bregs as well as the Foxp3 gene expression but not IL-10 were significantly decreased in GD group compared with the healthy controls. The frequency of Th17 together with the gene expressions of RORγt and IL-17 were significantly increased in the GD group. Furthermore, the Th17/Treg ratio was also significantly higher in GD group. A significant positive correlation between Th17 and TSAb (r = 0.656, p < 0.001) but significant negative correlations between Treg/Breg and TSAb (r = -0.339, p = 0.032; r = -0.759, p < 0.001) were identified among the participants. This study indicated that increased Th17 and impaired Treg responses, along with a decreased number of CD19+CD1dhiCD5+ Breg cells, were involved in GD pathogenesis.

Quantitative and qualitative iNKT repertoire associations with disease susceptibility and outcome in macaque tuberculosis infection.

Correlates of immune protection that reliably predict vaccine efficacy against Mycobacterium tuberculosis (Mtb) infection are urgently needed. Invariant NKT cells (iNKTs) are CD1d-dependent innate T cells that augment host antimicrobial immunity through production of cytokines, including interferon (IFN)-γ and tumour necrosis factor (TNF)-α. We determined peripheral blood iNKT numbers, their proliferative responses and iNKT subset proportions after in vitro antigen expansion by α-galactosylceramide (αGC) in a large cohort of mycobacteria-naïve non-human primates, and macaques from Bacillus Calmette-Guerin (BCG) vaccine and Mtb challenge studies. Animals studied included four genetically distinct groups of macaques within cynomolgus and rhesus species that differ in their susceptibility to Mtb infection. We demonstrate significant differences in ex vivo iNKT frequency between groups, which trends towards an association with susceptibility to Mtb, but no significant difference in overall iNKT proliferative responses. Susceptible animals exhibited a skewed CD4+/CD8+ iNKT subset ratio in comparison to more Mtb-resistant groups. Correlation of iNKT subsets post BCG vaccination with clinical disease manifestations following Mtb challenge in the Chinese cynomolgus and Indian rhesus macaques identified a consistent trend linking increased CD8+ iNKTs with favourable disease outcome. Finally, a similar iNKT profile was conferred by BCG vaccination in rhesus macaques. Our study provides the first detailed characterisation of iNKT cells in macaque tuberculosis infection, suggesting that iNKT repertoire differences may impact on disease outcome, which warrants further investigation.

Invariant NKT cells contribute to chronic lymphocytic leukemia surveillance and prognosis.

Chronic lymphocytic leukemia (CLL) is characterized by the expansion of malignant CD5+ B lymphocytes in blood, bone marrow, and lymphoid organs. CD1d-restricted invariant natural killer T (iNKT) cells are innate-like T lymphocytes strongly implicated in tumor surveillance. We investigated the impact of iNKT cells in the natural history of the disease in the Eµ-Tcl1 (Tcl1) CLL mouse model and 68 CLL patients. We found that Tcl1-CLL cells express CD1d and that iNKT cells critically delay disease onset but become functionally impaired upon disease progression. In patients, disease progression correlates with high CD1d expression on CLL cells and impaired iNKT cells. Conversely, disease stability correlates with negative or low CD1d expression on CLL cells and normal iNKT cells, suggesting indirect leukemia control. iNKT cells indeed hinder CLL survival in vitro by restraining CD1d-expressing nurse-like cells, a relevant proleukemia macrophage population. Multivariable analysis identified iNKT cell frequency as an independent predictor of disease progression. Together, these results support the contribution of iNKT cells to CLL immune surveillance and highlight iNKT cell frequency as a prognostic marker for disease progression.

A naive-like population of human CD1d-restricted T cells expressing intermediate levels of promyelocytic leukemia zinc finger.

Rare CD1d-α-galactosylceramide-specific T cells that do not express the invariant Vα24 chain of human NKT cells were recently identified after expansion in vitro with the lipid Ag, but their phenotype and frequency in vivo and lineage relationship with NKT cells could not be elucidated. By using a CD1d tetramer-based method to enrich these cells from fresh peripheral blood, we demonstrated their naive-like CD62L(high)CD45RO(-)CD4(+) phenotype and relatively high frequency of ∼10(-5) in several healthy individuals. Notably, these cells expressed the NKT lineage-specific transcription promyelocytic leukemia zinc finger (PLZF), indicating a developmental relationship with NKT cells and ruling out the possibility that they were conventional MHC-restricted T cells cross-reacting against CD1d-α-galactosylceramide. Although PLZF is known to direct the effector program of NKT cells, we show in this study that the naive-like cells expressed it at a significantly lower amount than NKT cells. Further, we present mouse studies demonstrating a sharp PLZF expression threshold requirement for induction of the effector phenotype. These findings directly demonstrate in vivo the existence of naive-like CD1d-restricted human T cells marked by intermediate levels of PLZF.

Low levels of soluble CD1d protein alters NKT cell function in patients with rheumatoid arthritis.

CD1d molecules on the cell surface play a critical role in the presentation of glycolipid antigens to natural killer T (NKT) cells. We previously showed that the human CD1d gene has 8 splice variants, one of which is a soluble form lacking the beta2-m and transmembrane domains. This study focused on soluble CD1d (sCD1d) by generating recombinant sCD1d proteins and assaying them in plasma using a newly established ELISA method. The amount of sCD1d proteins in plasma was significantly decreased in rheumatoid arthritis (RA) patients (55.2+/-13.3 years, mean +/-SD) compared with healthy donors (31.2+/-7.4 years). Plasma sCD1d protein levels correlated with the number of NKT cells (TCR V alpha 24+ V beta 11+CD3+) in peripheral blood mononuclear cells (r(2)=0.061). Furthermore, sCD1d proteins induced IFN-gamma production from NKT cells, but neither IL-4 nor IL-10. These findings suggest that the low plasma levels of sCD1d protein in RA patients reduce the number and thus activation of peripheral NKT cells. It is therefore hypothesized that sCD1d stimulates NKT cells and low plasma sCD1d levels in RA reflect a pathogenic mechanism associated with a decrease in NKT cells.