Myeloid cell-like transcript 2 is related to liver inflammation and the pathogenesis of hepatitis B via the involvement of CD8+T cell activation

TREML2 enhances sensitivity of acute myeloid leukemia cells to chemotherapy by inhibiting the NF-κB/CXCL10 pathway

The triggering receptors expressed on myeloid cells (TREMs) family of cell surface receptors are mainly expressed by myeloid cells. The expression profile of TREM-like 2 (TREML2), a TREM family member, in patients with acute myeloid leukemia (AML) is unknown. In this study, we aimed to elucidate the role of TREML2 in the development of AML. We analyzed the TREML2 expression profile in patients with AML. TREML2 was expressed at lower levels in patients with AML than in healthy individuals. The partial remission (PR) + no remission (NR) group showed lower TREML2 expression levels and a poorer chemotherapy response than that observed in the complete remission group. Overall survival was significantly shorter in the group with low TREML2 expression levels than in the group with high TREML2 expression levels. TREML2 inhibited the proliferation of AML cells and enhanced the sensitivity of AML cells to doxorubicin. Mechanistically, TREML2 reduced C-X-C motif chemokine ligand 10 expression levels by inhibiting the nuclear factor kappa B pathway. Taken together, we demonstrate that TREML2 has diagnostic value as a potential indicator of AML and that upregulation of TREML2 may be a new strategy to overcome doxorubicin resistance for AML treatment.

Programming effects of intrauterine hyperthermia on adrenal gland development

Maternal heat stress during late pregnancy can lead to intrauterine hyperthermia and affect fetal hypothalamic-pituitary-adrenal axis development and function. Herein, we investigated the effects of chronic environmental heat stress exposure of Holstein cows in the last 2 mo of gestation on their offspring's adrenal gland histomorphology and transcriptome. Cows in their last 54 ± 5 d of gestation were either heat stressed (housed under the shade of a freestall barn) or provided heat stress abatement via active cooling (via water soakers and fans) during a subtropical summer (temperature-humidity index >68). Respiration rate (RR) and skin temperature (ST) were elevated in heat-stressed dams relative to the cows with access to heat abatement (23 breaths/min and 2°C higher for RR and ST, respectively). Heifers born to heat-stressed cows experienced heat stress in utero (HS), whereas heifers born to actively cooled cows did not (CL). The adrenal gland was harvested from 6 heifers per group that were euthanized at birth (d 0; n = 12) or 1 wk after weaning (d 63; n = 12). Circulating cortisol was measured from blood samples collected weekly throughout the preweaning period. At d 63, heifers that experienced HS while developing in utero had heavier adrenal glands, with a greater total tissue surface area and thickness of the zona glomerulosa (ZG), fasciculata (ZF), and reticularis (ZR), compared with CL heifers. In addition, the adrenal gland of HS heifers had fewer cells in the ZG, more and larger cells in the ZF, and larger cells in the ZR, relative to CL heifers. Although no changes in circulating cortisol were observed through the preweaning period, the transcriptomic profile of the adrenal tissue was altered by fetal exposure to hyperthermia. Both at birth and on d 63, approximately 30 pathways were differentially expressed in the adrenal glands of HS heifers relative to CL. These pathways were associated with immune function, inflammation, prolactin signaling, cell function, and calcium transport. Upstream regulators significantly activated or inhibited in the adrenal glands of heifers exposed to intrauterine hyperthermia were identified. Maternal exposure to heat stress during late gestation caused an enlargement of their offspring's adrenal glands by inducing ZG and ZF cell hypertrophy, and caused gene expression changes. These phenotypic, histological, and molecular changes in the adrenal gland might lead to alterations in stress, immune, and metabolic responses later in life.

Who is who within the universe of TREM-like transcripts (TREML)?

The Triggering Receptor Expressed on Myeloid Cells (TREM) family of receptors plays a crucial role in the immune response across various species. Particularly, TREM-1 and TREM-2 have been extensively studied, both in terms of their applications and their expression sites and signaling pathways. However, the same is not observed for the other family members collectively known as TREM-like-transcripts (TREML). The TREML family consists of eight receptors, with TREML1-5 identified in humans and mice, TREML-6 exclusive found in mice, TREML-7 in dogs and horses, and TREML-8 in rabbits and opossums. Despite the limited data available on the TREML members, they have been implicated in different immune and non-immune activities, which have been proposed to display both pro and anti-inflammatory activities, and to influence fundamental biological processes such as coagulation, bone and neurological development. In this review, we have compiled available information regarding the already discovered members of the family and provided foundational framework for understanding the function, localization, and therapeutic potential of all TREML members. Additionally, we hope that this review may shed light on this family of receptors, whose underlying mechanisms are still awaiting elucidation, while emphasizing the need for future studies to explore their functions and potential therapeutic application.

Toll- like receptor 2 polymorphism and IL-6 profile in relation to disease progression in chronic HBV infection: a case control study in Egyptian patients

Chronic hepatitis B (CHB) has a wide range of outcomes depending on host immune responses mainly Toll-like receptors (TLRs) signaling and released cytokines. Toll-like receptor 2 (TLR2) single nucleotide polymorphisms (SNPs) and interleukin 6 (IL-6) may influence the course of CHB. We aimed to elucidate the relation between TLR-2 polymorphism, IL-6 profile, and CHB progression. We analyzed TLR-2 polymorphism (SNP; rs3804099) in 185 CHB patients and 60 controls using TaqMan allelic discrimination assay. Serum IL-6 levels were assessed by ELISA. IL-6 levels were considerably higher in active CHB and cirrhotic patients compared with inactive carriers and controls (P < 0.001). IL-6 showed positive correlation with ALT and advanced fibrosis in active CHB patients (r = 0.31, P = 0.02). A significant positive correlation was noticed between IL-6 and HBV DNA PCR in all CHB groups. TT genotype of rs3804099/TLR-2 was significantly more prevalent in inactive carriers compared to active hepatitis patients (P = 0.04, OR = 0.39 and 95% CI: 0.16-0.95). Both heterozygous CT and mutant TT genotypes were significantly more frequent among inactive carriers compared to cirrhotic patients (P = 0.01, OR = 0.33, 95% CI: 0.13-0.81 and P = 0.009, OR = 0.32, 95% CI: 0.13-0.77). TT genotype was significantly related to lower IL-6 levels in active hepatitis and cirrhotic groups (P = 0.005 and P = 0.001, respectively) showing that TLR mutations would be associated with milder hepatitis activity and lower possibility for disease progression. There may be a positive association between TLR2 rs3804099 polymorphism and hepatitis B activity. IL-6 is a good indicator of CHB disease progression.

Immune checkpoint of B7-H3 in cancer: from immunology to clinical immunotherapy

Immunotherapy for cancer is a rapidly developing treatment that modifies the immune system and enhances the antitumor immune response. B7-H3 (CD276), a member of the B7 family that plays an immunoregulatory role in the T cell response, has been highlighted as a novel potential target for cancer immunotherapy. B7-H3 has been shown to play an inhibitory role in T cell activation and proliferation, participate in tumor immune evasion and influence both the immune response and tumor behavior through different signaling pathways. B7-H3 expression has been found to be aberrantly upregulated in many different cancer types, and an association between B7-H3 expression and poor prognosis has been established. Immunotherapy targeting B7-H3 through different approaches has been developing rapidly, and many ongoing clinical trials are exploring the safety and efficacy profiles of these therapies in cancer. In this review, we summarize the emerging research on the function and underlying pathways of B7-H3, the expression and roles of B7-H3 in different cancer types, and the advances in B7-H3-targeted therapy. Considering different tumor microenvironment characteristics and results from preclinical models to clinical practice, the research indicates that B7-H3 is a promising target for future immunotherapy, which might eventually contribute to an improvement in cancer immunotherapy that will benefit patients.

Immunomodulatory Properties of Immune Checkpoint Inhibitors-More than Boosting T-Cell Responses?

The approval of immune checkpoint inhibitors (ICI) that serve to enhance effector T-cell anti-tumor responses has strongly improved success rates in the treatment of metastatic melanoma and other tumor types. The currently approved ICI constitute monoclonal antibodies blocking cytotoxic T-lymphocyte-associated protein (CTLA)-4 and anti-programmed cell death (PD)-1. By this, the T-cell-inhibitory CTLA-4/CD80/86 and PD-1/PD-1L/2L signaling axes are inhibited. This leads to sustained effector T-cell activity and circumvents the immune evasion of tumor cells, which frequently upregulate PD-L1 expression and modulate immune checkpoint molecule expression on leukocytes. As a result, profound clinical responses are observed in 40-60% of metastatic melanoma patients. Despite the pivotal role of T effector cells for triggering anti-tumor immunity, mounting evidence indicates that ICI efficacy may also be attributable to other cell types than T effector cells. In particular, emerging research has shown that ICI also impacts innate immune cells, such as myeloid cells, natural killer cells and innate lymphoid cells, which may amplify tumoricidal functions beyond triggering T effector cells, and thus improves clinical efficacy. Effects of ICI on non-T cells may additionally explain, in part, the character and extent of adverse effects associated with treatment. Deeper knowledge of these effects is required to further develop ICI treatment in terms of responsiveness of patients to treatment, to overcome resistance to ICI and to alleviate adverse effects. In this review we give an overview into the currently known immunomodulatory effects of ICI treatment in immune cell types other than the T cell compartment.

The Role of TREML2 in Alzheimer's Disease

Late-onset Alzheimer's disease (AD) accounts for most of all AD casesand is currently considered a complex disorder caused by a combination of environmental and genetic factors. As an important family member of triggering receptor expressed on myeloid cells (TREM), TREM-like transcript 2 gene (TREML2) locates on human chromosome 6p21.1, a newly-identified hot zone for AD susceptibility, and encodes atransmembrane immune receptor. Emerging evidence implied a potential role of TREML2 in the susceptibility and pathogenesis of AD. Here, we review the recent literature about the association of TREML2 variants with AD risk and disease endophenotypes. Moreover, we summarize the latest findings regarding cellular localization and biological functions of TREML2 and speculate its possible role in AD pathogenesis. In addition, we discuss future research directions of TREML2 and AD.

Entecavir add-on Peg-interferon therapy plays a positive role in reversing hepatic fibrosis in treatment-naïve chronic hepatitis B patients: a prospective and randomized controlled trial

BACKGROUND

The efficacy of entecavir (ETV) add-on peg-interferon therapy compared with ETV monotherapy in treatment-naïve hepatitis B virus (HBV) patients remains controversial. We investigated whether adding peg-interferon to ongoing ETV treatment leads to a better curative effect or not.

METHODS

All patients have been recruited between August 2013 and January 2015 from the Shanghai Public Health Clinical Center and Zhongshan Hospital (China). Eligible HBV patients (n = 144) were randomly divided (1:1) to receive either ETV monotherapy (n = 70) or peg-interferon add-on therapy from week 26 to 52 (n = 74). Patients were followed-up for at least 2 years. Indexes including hepatitis B surface antigen (HBsAg) and hepatitis B e antigen (HBeAg) seroconversion rate, sustained virologic response, transient elastography value, and histological scores were evaluated every 3 months until the end of the study. The rate of patients with HBsAg loss was defined as the primary endpoint criteria.

RESULTS

At week 26, no patient achieved HBsAg seroconversion in either group. At week 52, one patient in the monotherapy group was HBsAg-negative but there was none in the combination therapy group. The monotherapy group showed significantly better liver function recovery results than the combination therapy group. At week 78, one patient in the combination group had HBsAg seroconverted. At week 104, only three patients in the combination therapy group were HBsAg-negative compared with one patient in monotherapy. The mean alanine aminotransferase and aspartate aminotransferase levels and transient elastography values decreased significantly compared with baseline. Both groups showed a favorable decrease in alpha-fetoprotein (monotherapy: 4.5 [2.8, 7.1] vs. 2.2 [1.8, 3.1] ng/mL, P < 0.001; combination therapy: 5.7 [3.0, 18.8] vs. 3.2 [2.0, 4.3] ng/mL, P < 0.001) and an improved result of liver biopsy examination scores. The combination group showed a better improvement in histology compared with the monotherapy group (mean transient elastography value 6.6 [4.9, 9.8] vs. 7.8 [5.4, 11.1] kPa, P = 0.028). But there was no significant difference in HBsAg conversion rate (1.8% [1/56] vs. 4.1% [3/73], P = 0.809) and HBeAg conversion rate (12.5% [7/56] vs. 11.0% [8/73], P = 0.787), as well as HBV-DNA, sustained virologic response (93.2% vs. 98.5%, P = 0.150) between the two groups.

CONCLUSIONS

Both therapies supported liver function recovery and histology improvement. Combination therapy did not show better anti-viral efficacy in HBsAg or HBeAg seroconversion compared with monotherapy. However, combination therapy played a more positive role in reversing hepatic fibrosis compared with monotherapy.

TRIAL REGISTRATION

ClinicalTrials.gov: NCT02849132; https://clinicaltrials.gov/ct2/show/NCT02849132.