bluuebunny/crossref_metadata_2025_split huggingface dataset:
Mechanisms governing human memory-like natural killer cell function.
Authors: Wagner Julia A , Berrien-Elliott Melissa M , Rosario Maximillian , Jewell Brea A , Leong Jeffrey W , Schappe Timothy K , Abdel-Latif Sara , Fehniger Todd A 
Published: January 2023

Abstract
Natural killer (NK) cells are innate lymphoid cells critical for host defense against viral infection and malignant transformation. NK cells exhibit innate immunologic memory in response to specific haptens, viruses, or combined cytokine pre-activation. Human cytokine-induced memory-like NK cells, generated by overnight pre-activation with IL-12, IL-15, and IL-18, respond more robustly to numerous stimuli (including leukemia target cells) for weeks to months following the initial activation. The mechanisms responsible for the enhanced effector function of human memory-like NK cells are poorly understood. We hypothesized that memory-like NK cell differentiation alters the balance of signal integration downstream of activating and inhibitory receptors. NK cells achieve functional competence through self-MHC class I interactions (licensing) during maturation; if this does not occur, NK cells remain anergic. We tested this hypothesis using normal donors with licensed and unlicensed NK cell populations. We observed that cytokine pre-activation increases IFN-γ production by both licensed and unlicensed NK cells in response to tumor targets, activating receptor (FcγRIIIa) ligation, or cytokine stimulation. In fact, in response to cytokine stimulation, memory-like NK cells produce significantly more IFN-γ than controls with no impact of licensing. We observed no difference in the expression level of several signaling adaptor molecules or in phospho-signaling downstream of FcγRIIIa ligation in memory-like vs. control NK cells. We are currently investigating epigenetic modification of the IFN-γ gene locus in memory-like NK cells as a potential mechanism for their enhanced function; updated results will be presented.
Influence of M2b macrophage elimination on the wound healing responses in severely burned mice
Authors: Ito Ichiaki , Herndon David N , Suzuki Fujio , Kobayashi Makiko 
Published: January 2023

Abstract
To restore the impaired antibacterial resistance of burn patients, we performed M2bMϕ elimination using CCL1 antisense ODN. However, our treatment with the M2bMϕ polarizer includes a concern about the delay or disturbance of wound healing, because M2a and M2cMϕ distributed in tissues surrounding the burn area are known to be indispensable for host wound healing responses. In this study, the influence of M2bMϕ elimination on wound healing responses was investigated in severely burned mice. Mice 10 days after burn injury (day-10 burn mice) were treated with the ODN (s.c., 10 μg/mouse). Dermal F4/80+ cells (Mϕ) from these mice were analyzed for the expression of IL-10 (a biomarker of M2Mϕ), Arg1 and Ym1 (biomarkers of M2a and M2cMϕ), and LIGHT (a biomarker of M2bMϕ). Also, these dermal Mϕ were tested for the production of fibronectin and collagen (wound healing-related soluble factors) by ELISA. In the results, the increased expression of IL-10, Arg1, Ym1, and LIGHT mRNA was shown in dermal F4/80+ cells of day-10 burn mice, as compared to that of normal mice. Similarly, Arg1 and Ym1 mRNAs, but not LIGHT mRNA, were expressed by the same cells of day-10 burned mice treated with the ODN. Similar amounts of wound healing-related soluble factors were produced by dermal Mϕ from day-10 burned mice and the same mice treated with the ODN. These results indicate that the delay or disturbance of wound healing is minimal in severely burned hosts with eliminated M2bMϕ.
IL-15 complex-stimulated NK cells protect mice from cerebral malaria
Authors: Burrack Kristina Stoermer , Hamilton Sara E. , Jameson Stephen C. 
Published: January 2023

Abstract
Cerebral malaria (CM) is one of the most lethal complications of Plasmodium falciparum infection, responsible for a large fraction of the nearly one million malaria-related deaths annually. Infection of susceptible mouse strains such as C57BL/6 with Plasmodium berghei ANKA (PbA) induces a fatal neurological syndrome from 6–10 days post-infection (dpi) resulting from CD8 T cell-mediated damage to the CNS. We found that treatment of C57BL/6 mice with interleukin (IL)-15 complexes (IL-15C; IL-15 bound to an IL-15Rα-Fc fusion protein) prevented the development of PbA-induced CM. Rescue from CM was not associated with reduced parasitemia at 5 dpi. Instead, IL-15C treatment resulted in reduced CD8 T cell activation in the brain at 6 dpi and reduced blood brain barrier breakdown. In addition, adoptive transfer of IL-15C-stimulated natural killer (NK) cells (but not CD8+ T cells) was sufficient to prevent CM. IL-15C and similar complexes formed with IL-2 (IL-2C; IL-2 bound to the anti-IL-2 S4B6 antibody) both cause robust expansion and activation of NK cells but, unexpectedly, NK cells from mice treated with IL-2C failed to protect against CM. Comparative RNAseq analysis of IL-15C and IL-2C-treated NK cells identified novel gene expression patterns, demonstrating previously unappreciated differences between these cytokine complex signaling cascades in NK cells; the functional significance of these differences is being assessed. These data indicate that NK cells – which are typically involved in promoting inflammatory responses – can restrain damaging immune responses, and that differences between the activation of NK cells by IL-2C and IL-15C regulates their capacity to control the inflammatory response to blood stage malaria infection.
NLRX1 modulates the balance between NLRP3 inflammasome activation and NF-kB signaling during Fusobacterium nucleatum infection.
Authors: Hung Shu-Chen , Huang Pei-Rong , Bui Fiona Q , Ojcius David 
Published: January 2023

Abstract
NOD-like receptors (NLRs) play an important role in regulation of host innate immunity, yet their role in periodontitis remains to be defined. NLRX1, a member of the NLR family that localizes to mitochondria, modulates mitochondrial ROS (mROS) generation. mROS has been shown to activate the NLRP3 inflammasome, yet the role of NLRX1 in NLRP3 inflammasome activation has not been examined. In this study, we revealed the mechanism by which NLRX1 positively regulates ATP-elicited NLRP3 inflammasome activation through mROS in gingival epithelial cells (GECs). Fluorescence microscopy showed that depletion of NLRX1 by shRNA attenuates ATP-induced mROS generation and redistribution of the NLRP3 inflammasome adaptor protein, ASC. Furthermore, depletion of NLRX1 inhibits Fusobacterium nucleatum infection-activated caspase-1, suggesting that it also inhibits the NLRP3 inflammasome. Therefore, we propose that NLRX1 may promote F. nucleatum-caused dysregulated pro-inflammatory responses in periodontitis. On the other hand, the mechanism by which F. nucleatum infection-induces IL-8 expression is still unclear. We showed that NLRX1 also acts as a negative regulator in NF-kB signaling to modulate IL-8 expression. Thus, NLRX1 stimulates detection of the pathogen F. nucleatum via the inflammasome, while dampening cytokine production. We expect that commensals should not activate the inflammasome, but NLRX1 should still decrease their ability to stimulate inflammation. We conclude that NLRX1 may act as a potential switch in regards to the virulence of F. nucleatum in healthy or diseased oral cavity.
Cytosolic entry of LPS and activation of noncanonical inflammasome via bacterial outer membrane vesicles
Authors: Rathinam Vijay , Vanaja Sivapriya Kailasan , Russo Ashley , Behl Bharat , Banerjee Ishita 
Published: January 2023

Abstract
Sensing of lipopolysaccharide (LPS) in the cytosol triggers caspase-11 activation and is central to host defense against Gram-negative bacterial infections and to the pathogenesis of sepsis. Most Gram-negative bacteria that activate caspase-11 however are not cytosolic and the underlying mechanism by which LPS from these bacteria gains access to caspase-11 in the cytosol remains elusive. Here we identify outer membrane vesicles (OMV) produced by Gram-negative bacteria as a vehicle that delivers LPS into the cytosol triggering caspase-11-dependent effector responses in vitro and in vivo. OMV are internalized by macrophages and LPS is released into the cytosol from early and late endosomes. The use of hypovesiculating bacterial mutants, compromised in their ability to generate OMV, reveal the importance of OMV in mediating the cytosolic localization of LPS. Collectively, these findings demonstrate a critical role for OMV in enabling the cytosolic entry of LPS and consequently caspase-11 activation during Gram-negative bacterial infections. In broader terms, our data reveal a fundamental mechanism that serves as a conduit to deliver pathogen-associated molecular patterns (PAMP) to the cytosol to alert the immune system. Our data suggest that OMV with the cargo of immunostimulatory PAMP represent a cardinal sign of infection with not only viable but also multiplying bacteria consistent with the “patterns of pathogenesis” hypothesis.
Unanchored Polyubiquitin Chains and Innate Immune Sensing of Influenza Virus Infection
Authors: Rajsbaum Ricardo , Bharaj Preeti 
Published: January 2023

Abstract
Innate immune responses are initiated when pattern recognition receptors detect incoming microbes and trigger signaling pathways leading to production of inflammatory cytokines and type-I interferons (IFNs). These signaling pathways are regulated by different cellular processes including the ubiquitin (Ub) system. Proteins covalently attached to K48-linked polyUb are targeted for degradation by the proteasome, whereas protein modification with K63-linked polyUb may have non-proteolytic-activating functions. Unanchored Ub chains that are not covalently attached to any protein are also important for kinase activation. We recently reported that the E3 ligase TRIM6 synthesizes unanchored K48-linked polyUb chains, which activate the IKKɛ kinase for induction of an antiviral response. To better understand the physiological role of unanchored polyUb during virus infection, we developed a system to isolate ubiquitin-interacting proteins from the lungs of influenza-infected mice. By using a proteomics approach we identified three RNA helicases that interact with unanchored polyUb chains in vivo. Knockdown analyses of these RNA helicases resulted in decreased IFN induction upon influenza virus infection, suggesting that they may be involved in viral RNA recognition. Therefore, unanchored polyUb chains are emerging as important players in viral sensing and innate immune signaling. Our approach provides a new strategy for the identification of Ub-binding proteins from in vivo samples.
The pro-apoptotic factor Bax regulates macrophage necrosis during Mycobacterial infection
Authors: Soler Francisco Jose Roca , Redmond Sarah , Ramakrishnan Lalita 
Published: January 2023

Abstract
In the zebrafish-Mycobacterium marinum model for tuberculosis infection, excess TNF triggers necrosis of infected macrophages which leads to exuberant extracellular bacterial growth and host susceptibility (Tobin et al., 2012; Roca and Ramakrishnan, 2013). It has been shown that in infected macrophages, excess TNF induces production of mitochondrial reactive oxygen species (ROS) which activate two death pathways that converge in macrophage necrosis: cyclophilin D-dependent mitochondrial transition pore and acid sphingomyelinase-dependent ceramide production that leads to lysosomal permeabilization.
In exploring the events downstream of lysosomal permeabilization, we found that ceramide acts in a Cathepsin D-dependent manner to induce cell death. In the cytosol Cathepsin D initiates the activation of pro-apoptotic factors including Bid and Bax. We engineered Bax mutants that lack its different functional domains and studied the ability of each mutant protein to regulate apoptosis and necrosis. Then we infected Bax-deficient zebrafish larvae expressing the Bax mutants that were unable to induce apoptosis. We found the BH3 domain, which is required for Bax oligomerization during apoptosis, not to be required for necrosis under excess TNF conditions. Rather, an N-terminal transmembrane helix suggested to be the first portion of Bax in contact with the mitochondrial membrane was found to be required for necrosis. Current studies are focused on understanding post-translational modifications of Bax that determine whether activation of the same protein promotes apoptosis or necrosis.
Influence of Ectromelia virus (ECTV-Mos) infection on mRNA transcript levels of selected genes encoding antiviral proteins in a macrophage cell line RAW 264.7 (in vitro studies).
Authors: Toka Felix N , Dolega Patryk , Gregorczyk Karolina , Bossowska Magdalena , Mielcarska Matylda , Szulc-Dabrowska Lidia 
Published: January 2023

Abstract
Poxviruses have evolved a number of mechanisms to avoid immune response by the infected host. We investigated the impact of poxvirus infection on the level of mRNA transcripts of selected genes encoding antiviral proteins in the macrophage cell line (RAW 264.7). We observed reduction of mRNA transcript level in four groups of signalling pathways (Toll-like receptor signalling, NOD-like receptor signalling, RIG-I-like receptor signalling, and Type I interferon signalling) involved in innate immune response. Seventy-three genes had a statistically significantly decreased mRNA expression, 4 genes had a statistically significantly sustained mRNA expression. Only Cxcl11 and Ifna2 were statistically significantly increased. The results confirmed that the mouse poxvirus ECTV may interfere with or inhibit many signalling pathways, which are involved in inducing an antiviral immune response in infected macrophages.
Neutrophilic inflammation promotes bacterial growth during Tuberculosis
Authors: Mishra Bibhuti B , Sassetti Christopher 
Published: January 2023

Abstract
Nitric oxide is generally assumed to protect from tuberculosis by inhibiting the growth of Mycobacterium tuberculosis (Mtb), thereby preventing tissue damage. In contrast, we report that nitric oxide protects the host by repressing a neutrophil recruitment cascade that requires IL-1, CXCR2 and 12-lipoxygenase (12-LOX)-derived eicosanoids. Inhibition of the neutrophil recruitment alone enables the susceptible NOS2 KO mice to control Mtb growth, suggesting that neutrophilic inflammation, not an intrinsic anti-bacterial defect, drives susceptibility. By using a library of bacterial transposon mutants as reporters of host derived stress conditions, we show that granulocytic inflammation generates a nutrient-replete growth-permissive environment for Mtb which obviates the need for essential virulence factors, including the siderophore, mycobactin, and the virulence-related lipid, phthiocerol dimycocerosate, that are otherwise indispensable for establishing infection. A similar inflammatory pathway promotes TB in humans, as human genetic polymorphism that increases 12-LOX expression is associated with TB risk. The concentration of 12-LOX products correlates with neutrophil numbers and bacterial burden in the bronchoalveolar lavage of patients with pulmonary tuberculosis. We propose that Mtb exploits the inflammatory response to preferentially replicate at sites of tissue damage that promote contagion.
A novel antimicrobial agent differentially impacts the immunological response of stimulated bovine monocytes.
Authors: Dawes Maisie Ernestene , Aguilar Jose S , Chitko-McKown Carol G. 
Published: January 2023

Abstract
Despite advances in anti-inflammatory therapy, the US cattle industry now loses over $1 billion annually due to Gram-negative infections. In light of reduced lymphocyte proliferation concurrent with decreased cyclooxygenase-2 and matrix metalloproteinase-9 expression in bovine lactoferrin (bLF)-supplemented cells, we intended to show that bLF and the lactoferricin B (LFcin B) peptide, proven antibiotic agents, can also serve as low-risk anti-inflammatory agents, and hypothesized their ability to influence p38 MAPK signaling which is critical in macrophage-mediated inflammation. While LF is present in neutrophils, it is anticipated that enzymatic activity within infective sites will heighten local LFcin B concentrations.
Following pre-treatment with either bLF, the selective p38 MAPK inhibitor SB203580 (SB), or LFcin B, monocytes isolated from healthy 1 wk. to 5 mo old cattle stimulated with either lipopolysaccharide (LPS) or anisomycin (Aniso), were evaluated for iNOS, IL-1β and TNF-α expression. Preliminary data show that like SB, both bLF and LFcin B significantly abrogate LPS- and Aniso-induced TNF- α expression. In contrast, iNOS expression was increased in cells co-cultured with either LPS or Aniso and each of the three inhibitors. While these results support our hypothesis, additional work is needed to decipher the mechanistic rationale for the immunomodulatory effects of bLF and LFcin B, and the basis for differential cytokine release.
CX3CR1 distinguishes three antigen-experienced CD8 T cell subsets with distinct migratory, functional and homeostatic properties
Authors: Gerlach Carmen , Moseman Ashley , Loughhead Scott , Alvarez David , von Andrian Ulrich H 
Published: January 2023

Abstract
Following infection, pathogen-specific T cells differentiate into diverse short-lived effectors (TEff) that give rise to long-lived memory (TMem) subsets. These T cell fate decisions and lineage relationships are poorly understood, in part, because available subset-defining markers do not adequately reflect existing heterogeneities. Here, we report that CX3CR1 identifies three distinct CD8+ TEff and TMem subsets.
CX3CR1 expression levels on TEff were indicative of TEff differentiation, and predictive of the magnitude and type of memory progeny. Classical central memory (TCM) and effector memory cells (TEM) were CX3CR1– and CX3CR1high, respectively. In addition, we identified a hitherto unrecognized CX3CR1int population. The fraction of CX3CR1int cells among antigen-experienced TMem was remarkably stable over the course of a year, while TEM gradually declined and TCM increased to be the largest subset by 10 months. Interestingly, CX3CR1int TMem had the highest proliferation rate of the three TMem subsets. While TCM and TEM were phenotypically stable over &gt;10 weeks at steady state, CX3CR1int TMem not only self-renewed, but also gave rise to bonafide TCM. This suggests that CX3CR1int TMem may contribute to the gradual increase in TCM. In contrast, re-infection resulted in unidirectional differentiation from TCM to CX3CR1int TMem to TEM.
The newly identified CX3CR1int TMem displayed unique migratory properties. Unlike CX3CR1high TEM, CX3CR1int gradually acquired lymph node homing capability. Moreover, parabiosis experiments and analysis of recirculating memory cells in thoracic duct lymph revealed that CX3CR1int TMem, not TEM, are the predominant T cell subset surveying non-lymphoid peripheral tissues.
High resolution phenotyping identifies NK cell subsets that distinguish healthy children and adults
Authors: Mahapatra Sanjana , Banerjee Pinaki , Minard Charles , Mace Emily , Vargas-Hernandez Alexander , Canter Debra , Forbes Lisa , Makedonas George , Lee Dean , Duryea Teresa , Shearer William T , Orange Jordan S 
Published: January 2023

Abstract
Natural killer (NK) cells possess an array of germline-encoded activating, inhibitory and adhesion receptors, the balance of which in concert with their developmental stage, determine their cytotoxic and cytokine-producing potential. Although NK cells develop in the bone marrow and secondary lymphoid tissues, substantive differentiation is apparent in the peripheral blood including known age-related variation. In order to gain greater insight into phenotypic and functional variation within peripheral blood NK cells across age groups, we used multi-parameter, polyfunctional flow cytometry to interrogate the NK cell variability in 20 healthy adults and 15 5–10, 11–15 and 16–20 year-old children. We found that the normative ranges in both adults and children displayed great inter-individual variation for most subsets. Children possessed &gt;76% unstimulated NK subsets coexpressing perforin and granzyme B as opposed to &gt;65% in adults. Children also had &gt;28% NK subsets expressing all adhesion receptors in our panel compared to half of that in adults. As examples, terminally differentiated CD16+CD57+CD11b+ NK cells were reduced after 16 years of age as well as NKp46, 2B4, CD107a and newly-synthesized perforin in adults. Although CD107a intensity and new perforin synthesis was lower in adults, induced levels of IFNγ (by intensity) was higher. Despite most receptors not differing in their overall expression levels, major phenotypic differences were revealed in the combinatorial expression of NK receptors between adults and children. Our findings identify previously unappreciated NK cell subsets potentially distinguishing children from adults and suggest functional correlates that may have relevance in age-specific host defense.
Broad analysis of MTB-specific CD4 T cell responses reveals long lasting effect from previous active TB
Authors: Lindestam Arlehamn Cecilia S , Carpenter Chelsea , McKinney Denise M. , Makgotlho Edward , Rozot Virginie , Hanekom Willem , Peters Bjoern , Scriba Thomas J , Sette Alessandro 
Published: January 2023

Abstract
We have performed a side-by-side comparison of the immunogenicity of 11 antigens currently in candidate TB vaccines in clinical trials and known CD4 epitopes using PBMCs from healthy individuals with latent M. tuberculosis (MTB) infection (LTBI, n=42) or with prior active TB disease (PATB, n=21). The PATB samples were further divided based on time since TB diagnosis; less or more than 6 years ago. The epitopes identified in these cohorts were categorized into (1) maintained latency (LTBI/PATB ratio &gt;2), (2) associated with continued control of MTB infection i.e. LTBI status, and (3) shared epitopes (LTBI/PATB ratio &lt;2). Interestingly, the response to the maintained latency epitopes was significantly higher in LTBIs and PATBs with a longer time since diagnosis compared to PATB less than 6 years ago, but no difference was observed for the shared epitopes. This suggests that progression to active TB and/or chemotherapy is associated with loss of recognition of the maintained latency epitopes, with reactivity gradually regained several years after TB treatment, when these individuals may have become re-infected. Differential reactivity in these cohorts was also revealed at the antigen level. The biological relevance of this was further demonstrated by phenotypic differences of MTB-specific T cells in these cohorts. These results demonstrate that a large panel of epitopes is required to reveal differences in immune reactivity between LTBIs and PATB and suggest that previous active TB disease provokes a long lasting influence on the immune response.