Differential iNKT and T Cells Activation in Non-Alcoholic Fatty Liver Disease and Drug-Induced Liver Injury

Background: Non-alcoholic fatty liver disease (NAFLD) and idiosyncratic drug-induced liver injury (DILI) could share molecular mechanisms involving the immune system. We aimed to identify activation immunological biomarkers in invariant natural killer T (iNKT) and CD4/CD8+ T cells in NAFLD and DILI. Methods: We analyzed the activation profile (CD69, CD25, and HLA-DR) and natural killer group 2 member D (NKG2D) on iNKT cells, and CD4/CD8 T cells in peripheral blood mononuclear cells from NAFLD, with or without significant liver fibrosis, and DILI patients. Results: There was an increase in iNKT cells in NAFLD patients compared to DILI or control subjects. Regarding the cellular activation profile, NAFLD with significant liver fibrosis (F ≥ 2) displayed higher levels of CD69+iNKT cells compared to NAFLD with none or mild liver fibrosis (F ≤ 1) and control patients. CD69+iNKT positively correlated with insulin resistance, aspartate aminotransferase (AST) level, liver fibrosis-4 index (FIB4) and AST to Platelet Ratio Index (APRI). DILI patients showed an increase in CD69+ and HLA-DR+ in both CD4+ and CD8+ T cells, detecting the most relevant difference in the case of CD69+CD8+ T cells. Conclusions: CD69+iNKT may be a biomarker to assess liver fibrosis progression in NAFLD. CD69+CD8+ T cells were identified as a potential distinctive biomarker for distinguishing DILI from NAFLD.

SARS-CoV-2 Spike Protein and Its Receptor Binding Domain Promote a Proinflammatory Activation Profile on Human Dendritic Cells

Dendritic cells (DCs) are the most potent antigen-presenting cells, and their function is essential to configure adaptative immunity and avoid excessive inflammation. DCs are predicted to play a crucial role in the clinical evolution of the infection by the severe acute respiratory syndrome (SARS) coronavirus (CoV)-2. DCs interaction with the SARS-CoV-2 Spike protein, which mediates cell receptor binding and subsequent fusion of the viral particle with host cell, is a key step to induce effective immunity against this virus and in the S protein-based vaccination protocols. Here we evaluated human DCs in response to SARS-CoV-2 S protein, or to a fragment encompassing the receptor binding domain (RBD) challenge. Both proteins increased the expression of maturation markers, including MHC molecules and costimulatory receptors. DCs interaction with the SARS-CoV-2 S protein promotes activation of key signaling molecules involved in inflammation, including MAPK, AKT, STAT1, and NFκB, which correlates with the expression and secretion of distinctive proinflammatory cytokines. Differences in the expression of ACE2 along the differentiation of human monocytes to mature DCs and inter-donor were found. Our results show that SARS-CoV-2 S protein promotes inflammatory response and provides molecular links between individual variations and the degree of response against this virus.

566 ATOR-1017, a second generation 4–1BB antibody with potential to enhance efficacy of PD-1 therapies

BackgroundATOR-1017 is a Fcγ-receptor (FcγR) crosslinking dependent agonistic IgG4 antibody targeting the costimulatory receptor 4 1BB, designed for improved tolerability and efficacy. 4-1BB is highly expressed on tumor infiltrating CD8+ T effector cells (T effs) in several cancer indications. By binding to 4-1BB, ATOR-1017 enhances the activity of tumor reactive T effs and NK cells within the tumor and induces a potent anti-tumor response. 4-1BB is a promising candidate for immunotherapy and holds great potential for combination with other immunomodulatory antibodies, targeting e.g. the PD-1 pathway.MethodsHuman 4-1BB knock-in transgenic mice with established murine colon carcinoma MC38 tumors were used to demonstrate anti-tumor efficacy after systemic treatment with ATOR-1017 in combination with anti-PD-1. Further, the effect of combining ATOR-1017 with anti-PD-1 on T cell activation (measured as production of IFNγ) was evaluated in a mixed lymphocyte reaction (MLR) assay with human primary CD4+ T cells and mature monocyte-derived DCs (mDC) expressing endogenous levels of both 4-1BB and PD-1.ResultsATOR-1017 in combination with anti-PD-1 improved survival and reduced tumor growth signifcantly in human 4-1BB knock-in transgenic mice with established tumors compared with each monotherapy alone. The potential for combining ATOR-1017 and PD-1 was further supported by data from a MLR assay demonstrating that the combination of ATOR-1017 with anti-PD-1 induced a more potent CD4+ T cells activation than each monotherapy alone.The functional activation profile of ATOR-1017 is expected to minimize the risk of systemic immune activation and toxicity, by directing a potent immune response to immune cells in tumor tissue and tumor draining lymph nodes. This is supported by early data from the ongoing first-in-human phase I study where ATOR-1017 has been shown to be safe and tolerable.ConclusionsIn summary, these results support further clinical development of ATOR-1017 in combination with PD-1 antibodies. By combining ATOR-1017 with anti-PD-1, tumor infiltrating T cells can be more effectively activated and potentially increase the response rate in multiple indications.Ethics ApprovalAll animal procedures were in accordance to IACUC guidance

The benzene impact on programmed death of sperm cell

Introduction. Benzene and its derivatives enter organism from the natural environment are the sources of constant health danger, including reproductive system disorders. Purpose of the study. In vitro study of the modifying effect of benzene on the indices controlling the apoptosis of sperm cells. Materials and methods. The study includes data on 27 men from 41 to 51 years of age, apparently healthy, not in contact with harmful factors, and living in relatively favourable conditions. Using flow cytometry in the ejaculated semen, we determined CD25+ and CD95+ markers, p53, bax, caspase-3 activity, percentage of AnnexinV-FITC+PI-, and AnnexinV-FITC+PI+-spermatozoa. The seminal fluid samples were incubated with benzene at a concentration of 0.001 µg/ml (experimental samples) for 72 hours at 370C to evaluate the effect of aromatic hydrocarbons on the indices controlling the apoptosis. Sperm samples incubated under identical conditions without benzene addition were used as control samples. Results. p53 content, caspase-3 activity, and the number of dead male germ cells (AnnexinV-FITC+PI+-spermatozoa) were found to decrease statistically significantly (p=0.023-0.026) in experimental semen samples after the addition of benzene (by 50% of the initial levelon average). At the same time, the addition of benzene to the ejaculated semen samples did not change the early activation profile of gametes (according to CD25+ criteria), cells readiness to start FAS-dependent apoptosis (CD95+), and the number of spermatozoa marked for death by apoptosis (AnnexinV-FITC+PI- - spermatozoa). Conclusion. The results of immunological testing demonstrated that in vitro system benzene inhibits apoptosis and interferes with gamete life cycle . On the example of benzene, it was been demonstrated that haptenic contamination could alter sperm fertility associated with an imbalance of proapoptotic factors and impair ed male reproductive system function. The indices of programmed cell death bax, p53, caspase-3, CD25-positive, FAS-positive, AnnexinV-FITC+PI--sperm, and AnnexinV-FITC+PI+-sperm in the ejaculate are recommended for diagnosis and monitoring of sperm fertility disorders.

Slow manifolds within network dynamics encode working memory efficiently and robustly

Working memory is a cognitive function involving the storage and manipulation of latent information over brief intervals of time, thus making it crucial for context-dependent computation. Here, we use a top-down modeling approach to examine network-level mechanisms of working memory, an enigmatic issue and central topic of study in neuroscience. We optimize thousands of recurrent rate-based neural networks on a working memory task and then perform dynamical systems analysis on the ensuing optimized networks, wherein we find that four distinct dynamical mechanisms can emerge. In particular, we show the prevalence of a mechanism in which memories are encoded along slow stable manifolds in the network state space, leading to a phasic neuronal activation profile during memory periods. In contrast to mechanisms in which memories are directly encoded at stable attractors, these networks naturally forget stimuli over time. Despite this seeming functional disadvantage, they are more efficient in terms of how they leverage their attractor landscape and paradoxically, are considerably more robust to noise. Our results provide new hypotheses regarding how working memory function may be encoded within the dynamics of neural circuits.

Comparative Impact Study between Two Different Orthotic Clinical Approaches of Shank Vertical Angle Alignment on GRF Vectors and Activation Profile of Tibialis Anterior in Subjects with Post Stroke Hemiplegic using Solid Ankle Foot Orthosis: A Prospective Study

Background: Stroke is defined as the sudden onset of a focal neurologic deficit due to a presumed local disturbance in the blood supply to the brain. Orthotic treatment protocol in post stroke hemiplegic patients still is controversial topic. Numerous previous studies are concentrated upon providing the posterior heel wedge in outer side mainly with footwear’s heel rising associated with molded Solid Ankle Foot Orthosis (SAFO) but this is an attempt of this study to check the effects of insole posterior heel wedge as well as outsole posterior heel wedge in SAFO on temporal and kinetic gait parameters and activation profile of tibialis anterior muscle in post stroke hemiplegic patients. Aim & Objectives: The aim of the study was to compare between insole and outsole posterior heel wedge in molded solid ankle foot orthosis on working efficiency and activation profile of tibialis anterior muscle of the subject with post stroke hemiplegia. Materials and Methods: 30 subjects with post stroke hemiplegia were included in this study by convenient sampling method. The subjects were given with solid ankle foot orthosis with insole and outsole posterior heel wedge. The temporal and kinetic gait parameters and EMG of T.A muscle was measured using eWalk-NILD (MAT), Force plate and AD instrument power Lab. All the measurements were acquired at the time of measurement (Baseline data), time of discharge (Pre data) and after 4 weeks Post data was taken. Results: Pre-post conditions GRF Fx,Fy,Fz have significantly differences. Some parameters also have the non-significant differences. For all the cases to assist the parameters pre and post condition associated with and without AFO with insole posterior heel wedges on Group A and outsole Posterior heel wedge on Group B values are respected for GRF Fx pre without AFO (p= .147), pre with AFO (p= .037) and post without AFO (p= .253) with AFO (p=.009) For Fy pre without and with AFO (p=.025), (p =.682), post without and with AFO (p= .000), (p= .524) in case of Fz pre without and with AFO (p= .759) , (p= .999) post without and with AFO (p=.117), (p=.404 ). On TA muscle profile have also significant differences between two groups on pre without and with AFO (p=.005), (p= .613) and post without and with AFO (p= .000), (p= .000). Discussion & Conclusion: As per present perspective clinical evident report it is concluded that molded SAFO with outsole posterior heel wedge have a significance impact for positive influences on GRF, without any deficit contraction ( EMG signal) of T.A. muscle profile, as compare to insole posterior wedge with AFO. Key words: Hemiplegic, Gait kinetic parameters, Molded ankle foot orthosis, Insole and Outsole Posterior Heel Wedge.

Insulin resistance is linked to a specific profile of immune activation in human subjects

We tested the hypothesis that a particular immune activation profile might be correlated with insulin resistance in a general population. By measuring 43 markers of immune, endothelial, and coagulation activation, we have previously shown that five different immune activation profiles may be distinguished in 150 volunteers. One of these profiles, Profile 2, characterized by CD4+ T cell senescence, inflammation, monocyte, B cell, and endothelial activation, presented elevated insulinemia, glycemia, triglyceridemia, and γ-glutamyl transferase, a marker of liver injury, in comparison with other profiles. Our data are compatible with a model in which a particular immune activation profile might favor the development of insulin resistance and metabolic syndrome. In this hypothesis, identification of this profile, that is feasible with only 3 markers with an error rate of 5%, might allow to personalize the screening and prevention of metabolic syndrome-driven morbidities as liver steatosis.

Height, but not binding epitope, affects the potency of synthetic TCR agonists

Under physiological conditions, peptide-MHC (pMHC) molecules can trigger T-cell receptors (TCRs) as monovalent ligands, sparsely distributed on the plasma membrane of an antigen-presenting cell. TCR can also be activated by artificial clustering, such as with pMHC tetramers or antibodies; however, these strategies circumvent many of the natural ligand discrimination mechanisms of the T cell and can elicit non-physiological signaling activity. We have recently introduced a synthetic TCR agonist composed of an anti-TCRβ Fab′ antibody fragment covalently bound to a DNA oligonucleotide, which serves as a membrane anchor. This Fab′-DNA ligand efficiently activates TCR as a monomer when membrane-associated and exhibits a potency and activation profile resembling agonist pMHC. In this report, we explore the geometric requirements for effective TCR triggering and cellular activation by Fab′-DNA ligands. We find that T cells are insensitive to the ligand binding epitope on the TCR complex, but that length of the DNA tether is important. Increasing the intermembrane distance spanned by Fab′-DNA:TCR complexes decreases TCR triggering efficiency and T cell activation potency. These results establish design parameters for construction of synthetic TCR agonists that are able to activate polyclonal T cell populations, such as T cells from a human patient, in a similar manner as the native pMHC ligand.

Residual Viremia Is Linked to a Specific Immune Activation Profile in HIV-1-Infected Adults Under Efficient Antiretroviral Therapy

Chronic immune activation persists in persons living with HIV-1 even though they are aviremic under antiretroviral therapy, and fuels comorbidities. In previous studies, we have revealed that virologic responders present distinct profiles of immune activation, and that one of these profiles is related to microbial translocation. In the present work, we tested in 140 HIV-1-infected adults under efficient treatment for a mean duration of eight years whether low-level viremia might be another cause of immune activation. We observed that the frequency of viremia between 1 and 20 HIV-1 RNA copies/mL (39.5 ± 24.7% versus 21.1 ± 22.5%, p = 0.033) and transient viremia above 20 HIV-1 RNA copies/mL (15.1 ± 16.9% versus 3.3 ± 7.2%, p = 0.005) over the 2 last years was higher in patients with one profile of immune activation, Profile E, than in the other patients. Profile E, which is different from the profile related to microbial translocation with frequent CD38+ CD8+ T cells, is characterized by a high level of CD4+ T cell (cell surface expression of CD38), monocyte (plasma concentration of soluble CD14), and endothelium (plasma concentration of soluble Endothelial Protein C Receptor) activation, whereas the other profiles presented low CD4:CD8 ratio, elevated proportions of central memory CD8+ T cells or HLA-DR+ CD4+ T cells, respectively. Our data reinforce the hypothesis that various etiological factors shape the form of the immune activation in virologic responders, resulting in specific profiles. Given the type of immune activation of Profile E, a potential causal link between low-level viremia and atherosclerosis should be investigated.