Effect of Short-term TNF-α-stimulation of MC3T3-E1

Tumor necrosis factor-alpha (TNF-α) is an inflammatory cytokine known to cause bone resorption, swelling and edema during tissue organization. Conversely, TNF-α has also been shown to participate in tissue regeneration during the wound healing process. We have previously investigated the effects of TNF-α on human dental pulp cell differentiation. Dental pulp cells are composed of different cell types including primary odontoblasts and fibroblasts. We determined that the ratio of stem cells within the pulp cell population was increased following short-term stimulation with TNF-α. The aim of this study therefore was to investigate the effect of short-term stimulation with TNF-α on osteoblast-like MC3T3-E1 cell growth and differentiation. MC3T3-E1 cells were cultured in standard growth medium and on reaching sub-confluence were exposed to recombinant TNF-α (10 and 100 ng/ml) for 2 days prior to assessing their cell proliferation and differentiation properties in comparison to non-stimulated MC3T3-E1 cells (control). Although no significant differences in cell proliferation were observed between the TNF-α-stimulated and control groups, cell differentiation was delayed in the TNF-α-stimulated groups. In summary, short-term stimulation of cultured MC3T3-E1 cells with TNF-α had only minimal effect on their growth and differentiation

JunB Is Critical for Survival of T Helper Cells

Clonal expansion and differentiation of various T helper subsets, such as Th1, Th2, and Th17 cells, depend on a complex of transcription factors, IRF4 and a BATF-containing AP-1 heterodimer. A major BATF heterodimeric partner, JunB, regulates Th17 differentiation, but the role of JunB in other T helper subsets is not well understood. Here we demonstrate that JunB is required for clonal expansion of Th1, Th2 and Th17 cells. In mice immunized with lipopolysaccharide (LPS), papain, or complete Freund’s adjuvant (CFA), which induce predominantly Th1, Th2 and Th17 cells, respectively, accumulation of antigen-primed, Junb-deficient CD4+ T cells is significantly impaired. TCR-stimulated Junb-deficient CD4+ T cells are more sensitive to apoptosis, although they showed largely normal proliferation and cellular metabolism. JunB directly inhibits expression of genes involved in apoptosis, including Bcl2l11 (encoding Bim), by promoting IRF4 DNA binding at the gene locus. Taken together, JunB serves a critical function in clonal expansion of diverse T helper cells by inhibiting their apoptosis

Human immune and gut microbial parameters associated with inter-individual variations in COVID-19 mRNA vaccine-induced immunity

COVID-19 mRNA vaccines induce protective adaptive immunity against SARS-CoV-2 in most individuals, but there is wide variation in levels of vaccine-induced antibody and T-cell responses. However, the mechanisms underlying this inter-individual variation remain unclear. Here, using a systems biology approach based on multi-omics analyses of human blood and stool samples, we identified several factors that are associated with COVID-19 vaccine-induced adaptive immune responses. BNT162b2-induced T cell response is positively associated with late monocyte responses and inversely associated with baseline mRNA expression of activation protein 1 (AP-1) transcription factors. Interestingly, the gut microbial fucose/rhamnose degradation pathway is positively correlated with mRNA expression of AP-1, as well as a gene encoding an enzyme producing prostaglandin E2 (PGE2), which promotes AP-1 expression, and inversely correlated with BNT162b2-induced T-cell responses. These results suggest that baseline AP-1 expression, which is affected by commensal microbial activity, is a negative correlate of BNT162b2-induced T-cell responses.journal articl

JunB regulates homeostasis and suppressive functions of effector regulatory T cells

Foxp3-expressing CD4(+) regulatory T (Treg) cells need to differentiate into effector Treg (eTreg) cells to maintain immune homeostasis. T-cell receptor (TCR)-dependent induction of the transcription factor IRF4 is essential for eTreg differentiation, but how IRF4 activity is regulated in Treg cells is still unclear. Here we show that the AP-1 transcription factor, JunB, is expressed in eTreg cells and promotes an IRF4-dependent transcription program. Mice lacking JunB in Treg cells develop multi-organ autoimmunity, concomitant with aberrant activation of T helper cells. JunB promotes expression of Treg effector molecules, such as ICOS and CTLA4, in BATF-dependent and BATF-independent manners, and is also required for homeostasis and suppressive functions of eTreg. Mechanistically, JunB facilitates the accumulation of IRF4 at a subset of IRF4 target sites, including those located near Icos and Ctla4. Thus, JunB is a critical regulator of IRF4-dependent Treg effector programs, highlighting important functions for AP-1 in Treg-mediated immune homeostasis

Kinetic Energy and the Free Energy Principle in the Birth of Human Life

The retrospective noninterventional study investigated the kinetic energy of video images of 18 fertilized eggs (7 were normal and 11 were abnormal) recorded by a time-lapse device leading up to the beginning of the first cleavage. The norm values of cytoplasmic particles were measured by the optical flow method. Three phase profiles for normal cases were found regarding the kinetic energy: 2.199 × 10−24 ± 2.076 × 10−24, 2.369 × 10−24 ± 1.255 × 10−24, and 1.078 × 10−24 ± 4.720 × 10−25 (J) for phases 1, 2, and 3, respectively. In phase 2, the energies were 2.369 × 10−24 ± 1.255 × 10−24 and 4.694 × 10−24 ± 2.996 × 10−24 (J) (mean ± SD, p = 0.0372), and the time required was 8.114 ± 2.937 and 6.018 ± 5.685 (H) (p = 0.0413) for the normal and abnormal cases, respectively. The kinetic energy change was considered a condition for applying the free energy principle, which states that for any self-organized system to be in equilibrium in its environment, it must minimize its informational free energy. The kinetic energy, while interpreting it in terms of the free energy principle suggesting clinical usefulness, would further our understanding of the phenomenon of fertilized egg development with respect to the birth of human life

Effect of Short Term TNF-α Stimulation of BMSCs

Bone marrow-derived mesenchymal stem cells (BMSCs) have considerable potential for self-renewal and multi-differentiation. Tumor necrosis factor-α (TNF-α) is an inflammatory cytokine and is involved in tissue regeneration during wound healing. It was already reported that cultured human dental pulp cells acquire stem cell properties following short-term stimulation by TNF-α. However, it has not been clarified if BMSCs acquire stem cell properties after TNF-α treatment. The purpose of this study was to investigate the effect of short-term stimulation with TNF-α on BMSCs. Rat BMSCs were cultured up to 60% confluence and then incubated with 1–100 ng/ml of recombinant rat TNF-α (rTNF-α) for a further 2 days. After reaching subconfluence, cells were passaged once to remove rTNF-α completely before subsequent assays. Cells in the control group were passaged without stimulation. Expression levels of Nanog and Oct4 stem cell markers were significantly increased in the rTNF-α 10 ng/ml stimulation group. rTNF-α stimulation did not affect cell proliferation compared with the control group. However, rTNF-α stimulation led to a delay in cell differentiation. This study suggests that short-term TNF-α stimulation of BMSCs significantly increased their stem cell phenotype, but delayed their osteogenic cell differentiation

Phosphoenolpyruvate regulates the Th17 transcriptional program and inhibits autoimmunity

Aerobic glycolysis, a metabolic pathway essential for effector T cell survival and proliferation, regulates differentiation of autoimmune T helper (Th) 17 cells, but the mechanism underlying this regulation is largely unknown. Here, we identify a glycolytic intermediate metabolite, phosphoenolpyruvate (PEP), as a negative regulator of Th17 differentiation. PEP supplementation or inhibition of downstream glycolytic enzymes in differentiating Th17 cells increases intracellular PEP levels and inhibits interleukin (IL)-17A expression. PEP supplementation inhibits expression of signature molecules for Th17 and Th2 cells but does not signif-icantly affect glycolysis, cell proliferation, or survival of T helper cells. Mechanistically, PEP binds to JunB and inhibits DNA binding of the JunB/basic leucine zipper transcription factor ATF-like (BATF)/interferon regula-tory factor 4 (IRF4) complex, thereby modulating the Th17 transcriptional program. Furthermore, daily admin-istration of PEP to mice inhibits generation of Th17 cells and ameliorates Th17-dependent autoimmune encephalomyelitis. These data demonstrate that PEP links aerobic glycolysis to the Th17 transcriptional program, suggesting the therapeutic potential of PEP for autoimmune diseases.journal articl