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Although survival from breast cancer has dramatically increased, many will develop recurrent, metastatic disease. Unfortunately, survival for this stage of disease remains very low. Activating the immune system has incredible promise since it has the potential to be curative. However, immune checkpoint blockade (ICB) which works through T cells has been largely disappointing for metastatic breast cancer. One reason for this is a suppressive myeloid immune compartment that is unaffected by ICB. Cholesterol metabolism and proteins involved in cholesterol homeostasis play important regulatory roles in myeloid cells. Here, we demonstrate that NR0B2, a nuclear receptor involved in negative feedback of cholesterol metabolism, works in several myeloid cell types to impair subsequent expansion of regulatory T cells (T regs); T regs being a subset known to be highly immune suppressive and associated with poor therapeutic response. Within myeloid cells, NR0B2 serves to decrease many aspects of the inflammasome, ultimately resulting in decreased IL1β; IL1β driving T reg expansion. Importantly, mice lacking NR0B2 exhibit accelerated tumor growth. Thus, NR0B2 represents an important node in myeloid cells dictating ensuing T reg expansion and tumor growth, thereby representing a novel therapeutic target to re-educate these cells, having impact across different solid tumor types. Indeed, a paper co-published in this issue demonstrates the therapeutic utility of targeting NR0B2. • Regulatory T cells (Tregs) are associated with poor prognosis in several tumor types including breast cancer. • NR0B2 in myeloid cells suppresses several aspects of the inflammasome, culminating in decreased IL1β. • IL1β works to promote T reg expansion. • Loss of NR0B2 results in increased growth of mammary and melanoma tumors in mice. • NR0B2 represents a way to re-educate myeloid immune cells and relieve the immune-suppressive microenvironment of solid tumors. [ABSTRACT FROM AUTHOR]

Sepsis is characterized by the extensive release of cytokines and other mediators. It results in a dysregulated immune response and can lead to organ damage and death. Curcumin has anti-inflammatory properties and immunoregulation functions in various disorders such as sepsis, cancer, rheumatoid arthritis, cardiovascular diseases, lung fibrosis, gallstone formation, and diabetes. This paper investigates the effects of curcumin on immune status and inflammatory response in mice subjected to cecal ligation and puncture (CLP). Inflammatory tissue injury was evaluated by histological observation. Magnetic microbeads were used to isolate splenic CD4 + CD25 + regulatory T cells (Tregs), and phenotypes were then analyzed by flow cytometry. The levels of Foxp3 were detected by Western blot and real-time PCR and cytokine levels were determined by enzyme-linked immunosorbent assay. We found that the administration of curcumin significantly alleviated inflammatory injury of the lung and kidney in septic mice. The suppressive function of Treg cells was enhanced and the plasma levels of IL-10 increased after treatment with curcumin. Furthermore, the secretion of plasma TNF-α and IL-6 was notably inhibited in septic mice treated with curcumin and administration with curcumin could improve survival after CLP. These data suggest that curcumin could be used as a potential therapeutic agent for sepsis. [ABSTRACT FROM AUTHOR]

[Display omitted] • IDO1 induces immune tolerance within TME. • Serum profiling of IDO1 metabolites is of prognostic value. • IDO1 upregulation occurs after ICI therapy. • IDO1 inhibitors can be used safely with ICI therapy. • Epacadostat plus ICI renders promising clinical responses. • Clinical efficacy of anti-PD-L1/IDO inhibitor vaccination is promising. Metabolic alterations occur commonly in tumor cells as a way to adapt available energetic sources for their proliferation, survival and resistance. Indoleamine 2,3-dioxygenase 1 (IDO1) is an intracellular enzyme catalyzing tryptophan degradation into kynurenine. IDO1 expression shows a rise in the stroma of many types of human cancers, and it provides a negative feedback mechanism for cancer evasion from immunosurveillance. Upregulation of IDO1 correlates with cancer aggression, poor prognosis and shortened patient survival. The increased activity of this endogenous checkpoint impairs effector T cell function, increases regulatory T cell (Treg) population and induces immune tolerance, so its inhibition potentiates anti-tumor immune responses and reshapes immunogenic state of tumor microenvironment (TME) presumably through normalizing effector T cell activity. A point is that the expression of this immunoregulatory marker is upregulated after immune checkpoint inhibitor (ICI) therapy, and that it has inducible effect on expression of other checkpoints. These are indicative of the importance of IDO1 as an attractive immunotherapeutic target and rationalizing combination of IDO1 inhibitors with ICI drugs in patients with advanced solid cancers. In this review, we aimed to discuss about the impact of IDO1 on tumor immune ecosystem, and the IDO1-mediated bypass of ICI therapy. The efficacy of IDO1 inhibitor therapy in combination with ICIs in advanced/metastatic solid tumors is also a focus of this paper. [ABSTRACT FROM AUTHOR]

Zukamu granules (ZKMG), as the preferred drug for the treatment of colds in Uygur medical theory, has been used for 1500 years. It is also widely used in China and included in the National Essential Drugs List (2018 edition). It has unique anti-inflammatory, antitussive and analgesic effects. Aiming at the research of traditional Chinese medicine (TCM) with the characteristics of overall regulation of body diseases and the immune regulation mechanism with the concept of integrity, this paper put forward the integrated application of network composite module analysis and animal experiment verification to study the immune regulation mechanism of TCM. The active components and targets of ZKMG were predicted, and network module analysis was performed to explore their potential immunomodulatory mechanisms. Then acute lung injury (ALI) mice and idiopathic pulmonary fibrosis (IPF) rats were used as pathological models to observe the effects of ZKMG on the pathological conditions of infected ALI and IPF rats, determine the contents of Th1, Th2 characteristic cytokines and immunoglobulins, and study the intervention of GATA3/STAT6 signal pathway. The results of network composite module analysis showed that ZKMG contained 173 pharmacodynamic components and 249 potential targets, and four key modules were obtained. The immunomodulatory effects of ZKMG were related to T cell receptor signaling pathway. The validation results of bioeffects that ZKMG could carry out bidirectional immune regulation on Th1/Th2 cytokines in the stage of ALI and IPF, so as to play the role of regulating immune homeostasis and organ protection. The network composite module analysis and verification method is an exploration to study the immune regulation mechanism of TCM by combining the network module prediction analysis with animal experiments, which provides a reference for subsequent research. [Display omitted] [ABSTRACT FROM AUTHOR]

A recent paper by Shi et al. defines the role of regulatory T cells (Tregs) in white matter recovery after ischemic stroke. This study elucidates the mechanisms by which Tregs direct microglia to alter their phenotype to support oligodendrogenesis, thereby improving white matter integrity and functional recovery after stroke in mice. [ABSTRACT FROM AUTHOR]

Establishment and maintenance of pregnancy represents a challenge for the maternal immune system since it has to defend against pathogens and tolerate paternal alloantigens expressed in fetal tissues. Regulatory T (Treg) cells, a subset of suppressor CD4 + T cells, play a dominant role in the maintenance of immunological self-tolerance by preventing immune and autoimmune responses against self-antigens. Although localized mechanisms contribute to fetal evasion from immune attack, in the last few years it has been observed that Treg cells are essential in promoting fetal survival avoiding the recognition of paternal semi-allogeneic tissues by maternal immune system. Several functional studies have shown that unexplained infertility, miscarriage and pre-clampsia are often associated with deficit in Treg cell number and function while normal pregnancy selectively stimulates the accumulation of maternal forkhead-box-P3 + (FoxP3 + ) CD4 + Treg cells with fetal specificity. Some papers have been reported that the number of Treg cells persists at elevated levels long after delivery developing an immune regulatory memory against father's antigens, moreover these memory Treg cells rapidly proliferate during subsequent pregnancies, however, on the other hand, there are several evidence suggesting a clear decline of Treg cells number after delivery. Different factors such as cytokines, adipokines, pregnancy hormones and seminal fluid have immunoregulatory activity and influence the success of pregnancy by increasing Treg cell number and activity. The development of strategies capable of modulating immune responses toward fetal antigens through Treg cell manipulation, could have an impact on the induction of tolerance against fetal antigens during immune-mediated recurrent abortion. [ABSTRACT FROM AUTHOR]