A minority of Th1 and Tfh effector cells express survival genes shared by memory cell progeny that require IL-7 or TCR signaling to persist.

It is not clear how CD4 memory T cells are formed from a much larger pool of earlier effector cells. We found that transient systemic bacterial infection rapidly generates several antigen-specific T helper (Th)1 and T follicular helper (Tfh) cell populations with different tissue residence behaviors. Although most cells of all varieties had transcriptomes indicative of cell stress and death at the peak of the response, some had already acquired a memory cell signature characterized by expression of genes involved in cell survival.

Initial stage of titanium oxidation in Ti/CuO thermites: a molecular dynamics study using ReaxFF forcefields.

The paper elucidates the main driving mechanisms at play during the early stage of the Ti/CuO thermite reaction using reactive forcefields in the frame of molecular dynamics calculations. Results show that TiO preferentially forms in immediate contact to pure Ti at temperatures as low as 200 K rather than TiO. Increasing the temperature to 700 K, the 2 nm TiO in contact to Ti is found to be homogeneously depleted from half of its oxygen atoms.

Anisotropic atomistic shock response mechanisms of aramid crystals.

Aramid fibers composed of poly(p-phenylene terephthalamide) (PPTA) polymers are attractive materials due to their high strength, low weight, and high shock resilience. Even though they have widely been utilized as a basic ingredient in Kevlar, Twaron, and other fabrics and applications, their intrinsic behavior under intense shock loading is still to be understood. In this work, we characterize the anisotropic shock response of PPTA crystals by performing reactive molecular dynamics simulations.

Immune tolerance of food is mediated by layers of CD4 T cell dysfunction.

Gastrointestinal health depends on the adaptive immune system tolerating the foreign proteins in food. This tolerance is paradoxical because the immune system normally attacks foreign substances by generating inflammation. Here we addressed this conundrum by using a sensitive cell enrichment method to show that polyclonal CD4 T cells responded to food peptides, including a natural one from gliadin, by proliferating weakly in secondary lymphoid organs of the gut-liver axis owing to the action of regulatory T cells.

Dietary antigens suppress the proliferation of type 2 innate lymphoid cells by restraining homeostatic IL-25 production.

Dietary antigens affect the adaptive immunity of the host by inducing regulatory T cells and IgE-producing B cells. However, their roles in innate immune compartments such as innate lymphoid cells (ILCs) and intestinal epithelial cells (IECs) are unclear. Here, using antigen-free (AF) mice, which are germ-free (GF) mice fed with amino-acid-based diet, we found dietary proteins suppress the development of GATA-3-expressing ILC2s independent of the adaptive immune cells.

Atomic-level investigation on the oxidation efficiency and corrosion resistance of lithium enhanced by the addition of two dimensional materials.

Understanding the oxidation and corrosion characteristics of Lithium (Li)-based systems is critical to their successful use as a solid fuel in spacecraft, powerplants, rechargeable batteries, submarines, and many other aquatic and corrosive environments. This study offers a systematic roadmap for engineering the oxidation efficiency and corrosion resistance of Li-based systems using ReaxFF-based Reactive Molecular Dynamics (RMD) simulations for the first time. First, we explored the oxidation mechanism of bare Li (Li/O) at 1200 K, noticing that the oxidation process quickly ceases due to the creation of a passive oxide film on the Li surface.

Novel virus-like nanoparticle vaccine effectively protects animal model from SARS-CoV-2 infection.

The key to battling the COVID-19 pandemic and its potential aftermath is to develop a variety of vaccines that are efficacious and safe, elicit lasting immunity, and cover a range of SARS-CoV-2 variants. Recombinant viral receptor-binding domains (RBDs) are safe vaccine candidates but often have limited efficacy due to the lack of virus-like immunogen display pattern. Here we have developed a novel virus-like nanoparticle (VLP) vaccine that displays 120 copies of SARS-CoV-2 RBD on its surface.

Photoluminescence of blood by acidic hydrogen peroxide-A preliminary test.

In this study, the authors found that treating blood with 1 M HCl and 2% (w/v) 5-sulfosalicylic acid (SSA) in 1% (v/v) hydrogen peroxide mixture can produce photoluminescence of blood. SSA was added as a blood fixer. The photoluminescence was induced by irradiation of a forensic light source at 505 nm, which was detected using a 550 nm barrier filter.

Establishes Commensalism in Germ-Free Mice Through the Reversible Downregulation of Virulence Gene Expression.

The intestine harbors a complex community of bacterial species collectively known as commensal microbiota. Specific species of resident bacteria, as known as pathobiont, have pathogenic potential and can induce apparent damage to the host and intestinal inflammation in a certain condition. However, the host immune factors that permit its commensalism under steady state conditions are not clearly understood.

Two sequential activation modules control the differentiation of protective T helper-1 (Th1) cells.

Interferon-γ (IFN-γ)-producing CD4 T helper-1 (Th1) cells are critical for protection from microbes that infect the phagosomes of myeloid cells. Current understanding of Th1 cell differentiation is based largely on reductionist cell culture experiments. We assessed Th1 cell generation in vivo by studying antigen-specific CD4 T cells during infection with the phagosomal pathogen Salmonella enterica (Se), or influenza A virus (IAV), for which CD4 T cells are less important.

Characterization of the mechanical properties of van der Waals heterostructures of stanene adsorbed on graphene, hexagonal boron-nitride and silicon carbide.

Stanene has revealed a new horizon in the field of quantum condensed matter and energy conversion devices but its significantly lower tensile strength limits its further applications and effective operation in these nanodevices. Van der Waals heterostructures have given substantial flexibility to integrate different two-dimensional (2D) layered materials over the past few years and have proven highly functional with exceptional features, appealing applications, and innovative physics. Considerable efforts have been made for the preparation, thorough understanding, and applications of van der Waals heterostructures in the fields of electronics and optoelectronics.

Sulfurization of MoO in the Chemical Vapor Deposition Synthesis of MoS Enhanced by an HS/H Mixture.

The typical layered transition metal dichalcogenide (TMDC) material, MoS, is considered a promising candidate for the next-generation electronic device due to its exceptional physical and chemical properties. In chemical vapor deposition synthesis, the sulfurization of MoO powders is an essential reaction step in which the MoO reactants are converted into MoS products. Recent studies have suggested using an HS/H mixture to reduce MoO powders in an effective way.

Cutting Edge: Mouse SARS-CoV-2 Epitope Reveals Infection and Vaccine-Elicited CD8 T Cell Responses.

The magnitude of SARS-CoV-2-specific T cell responses correlates inversely with human disease severity, suggesting T cell involvement in primary control. Whereas many COVID-19 vaccines focus on establishing humoral immunity to viral spike protein, vaccine-elicited T cell immunity may bolster durable protection or cross-reactivity with viral variants. To better enable mechanistic and vaccination studies in mice, we identified a dominant CD8 T cell SARS-CoV-2 nucleoprotein epitope.

Growth Kinetics and Atomistic Mechanisms of Native Oxidation of ZrSSe and MoS Crystals.

A thorough understanding of native oxides is essential for designing semiconductor devices. Here, we report a study of the rate and mechanisms of spontaneous oxidation of bulk single crystals of ZrSSe alloys and MoS. ZrSSe alloys oxidize rapidly, and the oxidation rate increases with Se content.

Hybrid Fc-fused interleukin-7 induces an inflamed tumor microenvironment and improves the efficacy of cancer immunotherapy.

Objectives: Emerging oncotherapeutic strategies require the induction of an immunostimulatory tumor microenvironment (TME) containing numerous tumor-reactive CD8 T cells. Interleukin-7 (IL-7), a T-cell homeostatic cytokine, induces an antitumor response; however, the detailed mechanisms underlying the contributions of the IL-7 to TME remain unclear. Here, we aimed to investigate the mechanism underlying the induction of antitumor response by hybrid Fc-fused long-acting recombinant human IL-7 (rhIL-7-hyFc) through regulation of both adaptive and innate immune cells in the TME.

Dietary Glucose Consumption Promotes RALDH Activity in Small Intestinal CD103CD11b Dendritic Cells.

Retinal dehydrogenase (RALDH) enzymatic activities catalyze the conversion of vitamin A to its metabolite Retinoic acid (RA) in intestinal dendritic cells (DCs) and promote immunological tolerance. However, precise understanding of the exogenous factors that act as initial trigger of RALDH activity in these cells is still evolving. By using germ-free (GF) mice raised on an antigen free (AF) elemental diet, we find that certain components in diet are critically required to establish optimal RALDH expression and activity, most prominently in small intestinal CD103CD11b DCs (siLP-DCs) right from the beginning of their lives.

TCB2, a new anti-human interleukin-2 antibody, facilitates heterodimeric IL-2 receptor signaling and improves anti-tumor immunity.

IL-2 is a pleiotropic cytokine that plays an essential role in the survival, expansion, and function of CD8 T cells, regulatory T cells (Tregs), and natural killer (NK) cells. Previous studies showed that binding IL-2 with an anti-IL-2 monoclonal antibody (mAb) with a particular specificity could block its interaction with IL-2Rα, which is mainly expressed on Tregs. This selectivity can enhance the anti-tumor effects of IL-2 by activating CD8 T and NK cells, while disfavoring Treg stimulation.

Synergistically Chemical and Thermal Coupling between Graphene Oxide and Graphene Fluoride for Enhancing Aluminum Combustion.

Metal combustion reaction is highly exothermic and is used in energetic applications, such as propulsion, pyrotechnics, powering micro- and nano-devices, and nanomaterials synthesis. Aluminum (Al) is attracting great interest in those applications because of its high energy density, earth abundance, and low toxicity. Nevertheless, Al combustion is hard to initiate and progresses slowly and incompletely.

Bcl11b prevents catastrophic autoimmunity by controlling multiple aspects of a regulatory T cell gene expression program.

Foxp3 and its protein partners establish a regulatory T (T) cell transcription profile and promote immunological tolerance. However, molecular features contributing to a T-specific gene expression program are still incompletely understood. We find that the transcription factor Bcl11b is a prominent Foxp3 cofactor with multifaceted functions in T biology.

Food antigens drive spontaneous IgE elevation in the absence of commensal microbiota.

Immunoglobulin E (IgE), a key mediator in allergic diseases, is spontaneously elevated in mice with disrupted commensal microbiota such as germ-free (GF) and antibiotics-treated mice. However, the underlying mechanisms for aberrant IgE elevation are still unclear. Here, we demonstrate that food antigens drive spontaneous IgE elevation in GF and antibiotics-treated mice by generating T helper 2 (T2)-skewed T follicular helper (T) cells in gut-associated lymphoid tissues (GALTs).

Defect Healing in Layered Materials: A Machine Learning-Assisted Characterization of MoS Crystal Phases.

Monolayer MoS is an outstanding candidate for a next-generation semiconducting material because of its exceptional physical, chemical, and mechanical properties. To make this promising layered material applicable to nanostructured electronic applications, synthesis of a highly crystalline MoS monolayer is vitally important. Among different types of synthesis methods, chemical vapor deposition (CVD) is the most practical way to synthesize few- or mono-layer MoS on the target substrate owing to its simplicity and scalability.

Interleukin-2/antibody complex expanding Foxp3 regulatory T cells exacerbates Th2-mediated allergic airway inflammation.

Foxp3＋ regulatory CD4＋ T (Treg) cells play an essential role in preventing overt immune responses against self and innocuous foreign antigens. Selective expansion of endogenous Treg cells in response to the administration of interleukin (IL)-2/antibody complex, such as the IL-2/JES6-1 complex (IL-2C) in mice, is considered an attractive therapeutic approach to various immune disorders. Here, we investigated the therapeutic potential of IL-2C in allergic airway inflammation models.

Unregulated antigen-presenting cell activation by T cells breaks self tolerance.

T cells proliferate vigorously following acute depletion of CD4 Foxp3 T regulatory cells [natural Tregs (nTregs)] and also when naive T cells are transferred to syngeneic, nTreg-deficient hosts. Here, using mice raised in an antigen-free (AF) environment, we show that proliferation in these two situations is directed to self ligands rather than food or commensal antigens. In both situations, the absence of nTregs elevates B7 expression on host dendritic cells (DCs) and enables a small subset of naive CD4 T cells with high self affinity to respond overtly to host DCs: bidirectional T/DC interaction ensues, leading to progressive DC activation and reciprocal strong proliferation of T cells accompanied by peripheral Treg (pTreg) formation.

Cost-effective production of tag-less recombinant protein in Nicotiana benthamiana.

Plants have recently received a great deal of attention as a means of producing recombinant proteins. Despite this, a limited number of recombinant proteins are currently on the market and, if plants are to be more widely used, a cost-effective and efficient purification method is urgently needed. Although affinity tags are convenient tools for protein purification, the presence of a tag on the recombinant protein is undesirable for many applications.