bluuebunny/crossref_metadata_2025_split huggingface dataset:
The neuropeptide, neurokinin A, has divergent effects on mast cell function
Authors: Sumpter Tina L , Falo Louis D , Larregina Adriana T 
Published: January 2023

Abstract
Mast cells (MCs) play a critical role in initiation of cutaneous type 2 immune responses. In the cutaneous microenvironment, sensory nerve fibers form a cohesive unit with MCs. In this unit, MC function is likely affected by neuropeptides, such as neurokinin A (NKA). NKA is abundant in the skin, but the affects of NKA on cutaneous MCs have not been extensively reported. NKA signals preferentially through the neurokinin-2 receptor (NK2R). We hypothesized that NKA/NK2R interactions influence cutaneous MC function. The effect of NKA on MCs was evaluated in vivo using the MC/IgE-specific passive cutaneous anaphylaxis (PCA) model. NKA reduced IgE-initiated changes in ear thickness. Likewise, NK2R antagonism enhanced IgE-initiated ear thickness in the PCA model. Intracellular pathways mediating the effects of NKA were delineated using bone marrow derived MCs (BMMCs). BMMCs expressed NK2R protein constitutively and NK2R expression was up-regulated by IgE. Functionally, NKA increased the percentage of IgE-activated MCs releasing granules but repressed transcription and release of the type 2 cytokines, IL-4 and IL-13. Mechanistically, IgE-mediated granule release has been attributed to increased STAT3 activation, whilst IL-4 and IL-13 transcription in MCs is attributed to STAT5 activation. NKA augmented STAT3 phosphorylation in IgE-activated MCs but reduced STAT5 phosphorylation. In sum, NKA modifies IgE-initiated STAT3 and STAT5 activity, granule release and cytokine transcription in MCs in vitro and inhibits MC function in vivo. These data demonstrate a role for NKA in the regulation of MC processes involved in type 2 mediated allergic disorders.
Pyruvate dehydrogenase has a major role in mast cell function and its activity is regulated by mitochondrial MITF
Authors: Sharkia Israa , Erlich Tal Hadad , Landolina Nadine , Assayag Miri , Motzik Alex , Rachmin Inbal , Kay Gillian , Porat Ziv , Tshori Sagi , Berkman Neville , Levi-Schaffer Francesca , Razin Ehud 
Published: January 2023

Abstract

Background
We have recently observed that OXPHOS mediated ATP production is essential for mast cell function. Pyruvate dehydrogenase (PDH) is the main regulator of the Krebs cycle and is located upstream to the electron transport chain. However, the role of PDH in mast cell function has not been described. Microphthalmia transcription factor (MITF) regulates the development, number and function of mast cells. The localization of MITF to the mitochondria and its interaction with mitochondrial proteins has not been explored.

Objective
To explore the role played by PDH in mast cell exocytosis and to determine whether MITF is localized in the mitochondria and is involved in the regulation of PDH activity.

Methods
Experiments were performed in vitro using human and mouse mast cells and RBL cells and in vivo in mice. The effect of PDH inhibition on mast cell function was examined. PDH interaction with MITF was measured before and after immunological activation. Furthermore, mitochondrial localization of MITF and its effect on PDH activity were determined.

Results
PDH is essential for immunologically mediated degranulation of mast cells. Following activation PDH is serine dephosphorylated. In addition, we show for the first time that MITF is partially located in the mitochondria and interacts with PDH. This interaction is dependent on the phosphorylation state of PDH. Furthermore, mitochondrial MITF regulates PDH activity.

Conclusion
The association of mitochondrial MITF with PDH emerges as an important regulator of mast cell function. Our findings indicate that PDH could arise as a new target for the manipulation of allergic diseases.
Dendritic cell-based vaccine treated with polysorbitol transporter enhanced antigen-specific CD8+ T cell immune responses through cross-presentation
Authors: Kim Cheol Gyun , Kye Yoon Chul , Kim Narae , Kim Han Wool , Kim Girak , Han Seung Hyun , Yun Cheol-Heui 
Published: January 2023

Abstract
Cross-presentation of epitope from exogenous antigen onto MHC I molecule enhances CD8+ T cell activity is important in host protective immune responses against virus infections and cancer. We previously reported that polysorbitol transpoter (PST), prepared from sorbitol diacrylate and low-molecular-weight polyethylenimine, induces a long-term antigen specific B cell response and phagolysosomal escape of antigens in macrophages via mechanism called ‘proton-sponge effect’. Therefore, we hypothesize that PST could enhance the cross-presentation and antigen-specific CD8+ T cell immune responses.
In the present study, we tried to determine whether PST could enhance cross-presentation of DC using model antigen Ovalbumin (OVA). PST formed a nano-sized complex with OVA (OVA-PST) enhanced SIINFEKL peptide loading onto MHC I molecules. The results further showed that it enhanced OVA-specific CD8+ T cell proliferation and activation. However, PST was not able to upregulate co-stimulatory molecules and pro-inflammatory cytokines, which are necessary to induce adequate protective immune response. Together with OVA-PST, Monophospholipid A (MPLA), a nontoxic TLR4 agonist which is analog of lipid A also used as co-delivery agent in nanoparticle peptide vaccine, upregulated the effects of OVA-PST complexes. Finally, when PST-OVA and MPLA applied to DC-based vaccine for tumor therapy, survival enhanced in mouse engrafted with tumor. Collectively, these results suggested that the PST enhances cross-presentation in DCs together with antigen-specific CD8+ T cell immune responses. Therefore PST with MPLA could act to improve DC-based vaccine.
Peptidome Diversities of human leukocyte antigen (HLA-B) allotypes
Authors: Zaitouna Anita J , Basrur Venkatesha , Foster Leonard J , Carrington Mary , Raghavan Malini 
Published: January 2023

Abstract
The HLA class I genes encode proteins that present short peptide antigen to CD8 T cells, thereby alerting the immune system to the presence of intracellular pathogens and cancers. The HLA class I genes are highly polymorphic, and the polymorphisms influence their peptide-binding specificities. Each HLA variant binds to a diverse array of peptides, the peptidome. Much remains to be understood about HLA class I peptidome diversity variations and their influencing factors. Here we validate the use of Shannon entropy (SE) plots to quantify and compare the diversities of HLA class I peptidomes derived from multiple independently-derived mass spectrometric (MS) data sets. The intrinsic peptide-binding preferences of HLA class I molecules and/or their intracellular assembly characteristics could influence their peptidome diversities. In particular, tapasin is an assembly factor that edits and optimizes the peptide repertoire of many HLA class I molecules, but is non-essential for several other HLA class I molecules. It has been suggested that a tapasin-independent assembly pathway could result in a broader, more diverse peptide repertoire. However, MS-based comparisons indicate that, under cellular conditions of tapasin sufficiency, the peptidome of HLA-B*4405 (a prototypic tapasin-independent allotype) is not more diverse than that of HLA-B*4402 (a prototypic tapasin-dependent allotype). Rather, the intrinsic peptide-binding specificity of HLA-B4402 results in greater length and C-terminal sequence diversity of its peptidome. Together, these studies indicate that structural constraints imposed by MHC class I peptide binding grooves are key determinants of their peptidome diversities.
α-Galactosylceramide and all trans-retinoic acid work together to promote antigen presentation and antibody production
Authors: Chen Qiuyan , Wei Cheng-Hsin , Ross A. Catharine 
Published: January 2023

Abstract
α-galactosylceramide (αGalCer) and all trans-retinoic acid (RA) are both known as potent immune regulators on various steps of the immune responses. Our previous studies have shown that αGalCer and RA could regulate B cell differentiation in vitro and increase antibody production in vivo. To investigate the underlying mechanisms related to the antibody response, animal experiments (in 8-wk old female Balb/c mice) were performed to determine the antigen presentation and B cell response during primary immunization. In a one-day experiment, dextran-FITC or KLH-FITC was injected intravenously with or without αGalCer (2 μg in 100 μl PBS with antigen, iv) or RA (37.5 μg in 10 μl canola oil, oral dose); in a 10-day experiment, KLH was injected (100 μg/100 μl PBS) with or without αGalCer/RA treatment. Spleens were analyzed by flow cytometry and immunofluorescent staining. We observed that Dextran and KLH after 24h of injection were localized at the spleen marginal zone (MZ) area, with only KLH colocalized with the metallophilic macrophages; in the presence of αGalCer and RA, the band of metallophilic macrophages became wider. While dextran moved markedly toward the follicular area after treatment, KLH signal was not seen within the follicle, and also became weaker at the MZ area, suggesting the different presentation and processing mechanisms of the antigens. At day 10, substantially more active germinal centers were formed in the presence of αGalCer and RA, with more focused staining of CD23+GL-7+ cells, markers of germinal center B cells. B cell numbers were increased at both time points. Our study suggests that αGalCer and RA together may promote antigen presentation and induce B cell differentiation that ultimately increases antibody production.
Illuminating T cell – APC interactions using multispectral imaging flow cytometry.
Authors: Pugsley Haley Renee , Friend Sherree L. , Kong Raymond K. , Morrissey Philip 
Published: January 2023

Abstract
Interaction between antigen-specific T cells and antigen presenting cells (APC) cognate ligand involve reorganization of the cytoskeleton and recruitment of adhesive and signaling molecules to the site of intercellular contact. Sustained adhesion of T cells to APCs and formation of the immunological synapse after T cell receptor stimulation are required for the antigen-specific response. One way to measure an immunological synapse is by fluorescently labeling the molecules that have been recruited to the synapse and imaging by fluorescence microscopy. However, immunological synapses are rare and therefore difficult to analyze objectively and statistically by traditional microscopy methods. To overcome these problems, we employed the Amnis brand ImageStream to objectively collect imagery of large numbers of cells. In this study, Raji B cells loaded with Staphylococcal enterotoxin B (SEB) were incubated with human T cells to create T cell-APC conjugates. Cells were stained in various combinations for CD3, CD19, Actin, LFA-1, Lck and NFkB. Using multispectral imaging flow cytometry we demonstrate image-based parameters that were used to assess the frequency of conjugates with an organized immunological synapse, evaluate the specific location of the adhesion and signaling molecules LFA-1 and Lck within the immunological synapse complex and measure the nuclear localization of NFkB in the T cell-APC conjugates.
In vivo characterization of the immune response towards the pathogenic Escherichia coli antigen SslE and modulation of the intestinal microbiota
Authors: Naili Ilham , Baudner Barbara C , Bernalier-Donadille Annick , Pizza Mariagrazia , Desvaux Mickael , Jubelin Gregory , Buonsanti Cecilia 
Published: January 2023

Abstract
Pathogenic E. coli, both intestinal (InPEC) and extraintestinal (ExPEC), account for a wide range of diseases, which can be fatal across developing and developed countries. They can acquire a vast array of virulence factors which may dramatically increase the severity of the infection. Emergence of resistant strains often renders antibiotics inefficient; in the case of Shiga toxin-producing E. coli, antibiotics therapy can even be detrimental. Hence, an E. coli vaccine with broad coverage could be a promising alternative to prevent the spread of such diseases, while offering the potential for protection against several InPEC and ExPEC at once.
Using the «reverse vaccinology» approach on ExPEC strains, nine antigens were identified as protective against a murine sepsis model. With 82% protective efficacy, SslE (Secreted and Surface-associated Lipoprotein of E. coli) was the most potent candidate. Additional models showed SslE to also be cross-protective against other ExPEC strains. Functional assays have demonstrated in vitro and ex vivo that SslE is a mucinase which plays an important role in colonization and virulence of E. coli.
To better understand the mechanism behind such protection, we are investigating the intestinal and systemic immune responses obtained after immunization with SslE using different routes of administration. In-depth analysis of each regimen will allow us to determine the most efficient method of immunization for SslE to be protective. Further, using this selected model of immunization, we will evaluate the potential perturbation caused by SslE immunization on the murine intestinal microbiome. These findings will be important to help us optimize the development of a potential broad spectrum E. coli vaccine.
The human antibody 3E1 targets a novel epitope of the HA stem region to neutralize the H1N1 and H5N6 influenza A viruses
Authors: Sun Bing , wang Wen Shuai , Sun Xiao Yu , Li Yan bing , Chen Hua Lan , Ding Jian Ping 
Published: January 2023

Abstract
As influenza A viruses remain a major threat to human health worldwide, the discovery of broadly neutralizing monoclonal antibodies that recognize conserved epitopes would facilitate the development of antibody-based therapeutic strategies. In this study, we show that a novel VH4-4-encoded human mAb named 3E1 could neutralize H1 and H5 subtype viruses in vitro and protect mice against the H1N1 and H5N6 viruses by inhibiting the low pH-induced conformational rearrangement of hemagglutinin (HA), hence blocking membrane fusion. The crystal structures of 3E1 Fab in complex with HA of two H1N1 strains reveal that 3E1, with both heavy and light chains, binds to a novel epitope of the conserved HA stem region, comprising parts of the fusion peptide, the F subdomain and the outermost β-strand preceding helix A. Together, these data suggest the potential of 3E1 as a therapeutic drug and new strategies for the development of antiviral drugs and universal vaccines against H1 and H5 subtype viruses.
Macrophage selenoproteins restrict intracellular replication of Francisella tularensis
Authors: Markley R L. , Williamson David R. , Katkere Bhuvana , Dewan Kalyan K. , Shay Ashley E. , Sumner Sarah E. , Prabhu K. Sandeep , Kirimanjeswara Girish S 
Published: January 2023

Abstract
There has been a growing appreciation for the influence of dietary nutrients on the microbiome as well as host response to infectious disease. The micronutrient selenium (Se) is known to regulate immune functions via selenoproteins, a class of proteins that contain the 21st amino acid selenocysteine. However, the mechanisms by which selenoproteins regulate immune functions during an acute infection are not clear. Therefore, we investigated the role of macrophage (Mac) selenoproteins during an acute bacterial infection. Francisella tularensis (Ft.), the causative agent of tularemia, is a gram-negative intracellular bacterium. Since Ft. infects and replicates primarily in Macs, we measured the bacterial replication in Macs derived from TrspM mice that are unable to synthesize selenoproteins. TrspM Macs had uncontrolled replication of Ft. compared to wild-type (WT) Macs. Moreover, TrspM mice were more susceptible to Ft. infection and harbored significantly higher levels of bacteria in their livers and spleens as compared to WT mice, which suggests that Mac selenoproteins are essential for restricting bacterial replication and promoting host survival. Since Ft. replication is closely associated with autophagy, we investigated if the Mac selenoproteins had an effect on autophagy. In fact, our data indicates that selenoproteins inhibit autophagy, which may limit the availability of nutrients to the bacteria. Future studies will seek to establish the influence of selenoproteins on the microbiome and how these changes impact the infectious disease process. Our studies demonstrate that nutrients affect the outcome of an infection by influencing host immune response, and reveal potential novel targets for antibacterial therapies.
Protective effects of Δ9-Tetrahydrocannabinol (THC) results from alteration in lung dysbiosis mediated by SEB-induced acute lung injury
Authors: Mohammed Amira K. , Alghetaa Hasan F , Nagarkatti Prakash , Nagarkatti Mitzi 
Published: January 2023

Abstract
Inhalation of Staphylococcal Enterotoxin B (SEB) is known to induce acute lung injury (ALI) and studies from our laboratory have shown that THC, a psychoactive ingredient found in Cannabis sativa, can attenuate the ALI. In the current study, we investigated the role played by lung microbiota in ALI with or without THC treatment. A dual-dose of SEB was given to C3H/HeJ mice, which were then treated either with vehicle or THC. SEB-administration caused ALI and 100% mortality while all THC-treated mice survived and suppressed the inflammation in the lungs. Furthermore, lung microbiota was collected and 16S rRNA sequencing was performed. The data were analyzed to determine the alpha and beta diversity. The major phylum was Proteobacteria, class Alphaproteobacteria and orders were Caulobacterles and Rhodobacteralesin in the lungs of vehicle-treated SEB group. Moreover, THC treatment led to elevated Firmicutes phylum due to significant increase in the beneficial genus, Lactobacillus. Lipopolysaccharide (LPS), gram negative bacterial endotoxin was found at significantly higher concentration in the BALF of vehicle-treated group in comparison with THC-treated mice. Beneficial metabolome levels were significantly higher in the colonic flush of THC-treated mice when compared to vehicle-treated SEB group, specifically butyric, propionic and acetic acids. Together, our data suggest that THC attenuates SEB-induced mortality and ALI by altering the microbiota in the lungs (Supported by NIH grants P01AT003961, R01AT006888, R01ES019313, R01MH094755, P20GM103641, R01AI129788 to PN and MN and MoHESR fellowship for AKM).
House dust mite exposure upregulates C3a receptor expression in pulmonary innate immune cells during the sensitization phase of allergic asthma by an IL-33-dependent mechanism
Authors: Laumonnier Yves , Quell Katharina , Wiese Anna Valeska , Vollbrandt Tillman , Köhl Jörg 
Published: January 2023

Abstract
The anaphylatoxin C3a exerts its biologic functions through the activation of its cognate G-protein-coupled receptor C3a receptor (C3aR). C3aR mRNA expression has been described both in human and mouse lungs. However, no systematic analysis of C3aR expression at steady state and under pro-inflammatory conditions in the different pulmonary cell subsets has been done so far. Using a newly developed Tandem-dye (td)-Tomato-C3aR reporter knock-in mouse, we found C3aR expression in pulmonary eosinophils, resident CD11b+ conventional dendritic cells (cDC), and monocyte-derived DCs (moDC) at steady state. In contrast, pulmonary CD103+ cDCs and plasmacytoid DCs stained negative. Surprisingly, lung and bronchoalveolar alveolar macrophages (AMs), as well as neutrophils, lacked td-Tomato-C3aR. C3aR antibody staining revealed that only moDCs express the receptor at the cell surface.
House dust mite (HDM) is a potent allergen that drives the development of allergic asthma in humans. Using the td-Tomato-C3aR reporter mouse, we found that HDM exposure resulted in the upregulation of C3aR in AMs, eosinophils, CD11b+ cDCs, and moDCs during the early phase of HDM-induced allergic asthma. Further, C3aR translocated to the cell surface in eosinophils and AMs following HDM exposure. Importantly, intra-tracheal administration of IL-33, an alarmin released by epithelial cells upon allergen contact, recapitulated these results. In summary, our findings demonstrate that allergen contact triggers the upregulation of C3aR and its surface expression in previously negative innate immune cells from the lung by an IL-33 dependent mechanism. C3aR-mediated activation of innate immune cells may play a critical role for early asthma development.
Chronic stimulation results in NK cell function impairment mediated by NKG2D
Authors: Alvarez Maite , Baker Jeanette , Wenokur Arielle , Morrisson Alyssa R. , Pierini Antonio , Simonetta Federico , Negrin Robert S. 
Published: January 2023

Abstract
NK cell exhaustion (NCE) has been described as a defect of NK cell function due to sustained proliferation resulting in downregulation of eomesodermin and T-bet. Using murine models of chronic stimulation, we have identified here a molecular signature of NCE characterized by up-regulation of the terminal differentiation marker KLRG1 and down-regulation of eomesodermin and of the activating receptor NKG2D. We show that chronic stimulation of mice lacking NKG2D resulted in a minimized NCE compared to control mice, thus pointing to NKG2D as a crucial player in NCE. Interestingly, in vitro studies revealed that MULT1 and Rae1, stress molecules known as NKG2D ligands, are up-regulated during activation, leading to NKG2D cis-binding and to its internalization, and thus reducing NKG2D accessibility. In order to minimize the genotoxic stress caused by prolonged stimulation and prevent NCE, NK cells were treated with the ATM/ATR DNA damage pathway inhibitor KU55933 (KU). KU treatment during NK cell activation prevented NK cell exhaustion as revealed by preserved cell function, improved expression of activation markers and of genes involved in cell survival, and sustained expression of NKG2D. Importantly, the adoptive transfer of NK cells expanded ex vivo in the presence of KU resulted in better survival in A20 and B16F10 mouse models of cancer that can be eliminated in a NKG2D-dependent or -independent manner respectively. Collectively, these data demonstrate that NCE is indeed an intrinsic regulatory mechanism of NK cell activation regulated, at least in part, by NKG2D and that prevention of NCE is a promising strategy to improve NK cell-based immunotherapy.
Aging induced changes in the microbiome affect the crosstalk and activity of monocytes and B1a cells
Authors: Bodogai Monica , Moritoh Kanakoh , Kim Ki , Wu Jiejun , Mattison Julie , Biragyn Arya 
Published: January 2023

AbstractAging is thought to mostly dysregulate conventional B2 cells while leaving unaffected innate B1 cells. We recently questioned this assumption by providing evidence that upon aging, in humans, macaques and mice, B1a cells become converted into 4-1BBL+mTNFa+MHC class-IHiCD86Hi B cells (4BL cells) 1,2. Here we report that this conversion is induced by changes in the gut microbiota. Metabolites of the aging gut microbiota initiate monocyte infiltration in the omentum, where they convert B1a cells into 4BL cells. By utilizing 4-1BBL-41BB and mTNFa-TNFRII axes, 4BL cells further induce granzyme B (GrB)-expressing cytolytic CD8+T cells. Thus, for the first time, we provide a mechanistic proof that innate B1a cells also become dysregulated in aging of mammals, resulting in the loss of their immunosuppressive function and the gain of a new function – ability to induce potentially antitumor and autoimmune CD8+T cells. Our data shows the role of the microbiome/monocyte/B-cell/CD8-cell network in several aging-associated diseases.This work was supported by the Intramural Research Program, NIA/NIH, and CRADA with Janssen Research & Development, LLC, USA