bluuebunny/crossref_metadata_2025_split huggingface dataset:
Regulation of TLR9 signaling by N-glycosylation of UNC93B1
Authors: Song Hyun-Sup , Huh Ji-Won , Lee Yu-Ran , Jung Da-Jung , Yang Chorong , Kim You-Me 
Published: February 2023

Abstract
Nucleotide-sensing Toll-like receptors (TLRs), such as TLR3, 7, and 9, reside in the endolysosomal compartments to avoid activation by host DNA or RNA. Proper intracellular localization and signaling by these TLRs depend on the physical interaction with UNC93B1. Specific amino acid residues in UNC93B1 have been identified to affect the functions of endosolysomal TLRs. However, it is largely unknown how UNC93B1 differentially regulates individual TLRs.
Protein N-glycosylation controls folding, maturation, stability, localization and protein-interaction of target glycoproteins. In this study, we examined whether the N-glycosylation of UNC93B1 affects its properties and molecular function.
Using mutagenesis, we found that the N251 and N272 residues of UNC93B1 become N-glycosylated. We expressed wild type (WT) and N-glycosylation-defective UNC93B1 mutants (N251Q and N272Q) in UNC93B1-deficient cells and found that signaling of TLR9, but not that of other TLRs, were defective in UNC93B1 N272Q-expressing cells. The N272Q mutation did not affect the protein stability, localization, interaction of UNC93B1 and TLRs, nor did it prevent the CpG DNA-binding of TLR9. Nonetheless, upon CpG DNA stimulation, the recruitment of MyD88 to TLR9 was significantly inhibited in UNC93B1 N272Q-expressing cells compared to WT cells. Consequently, poor phosphorylation and degradation of I_B were observed in UNC93B1 N272Q-expressing cells. Combined, our data show that N-glycosylation of UNC93B1 specifically regulates TLR9 signaling by modulating the recruitment of MyD88 to TLR9.
In silico mapping of 14-3-3ζ and Human TRAF interaction
Authors: Gupta Anish U , Gupta Shrey , McGowan Jenna , Chakravarti Ritu 
Published: February 2023

Abstract
Recent advances show that the 14-3-3ζ protein participates in several immune regulations and is a unique regulator of IL-17A signal transduction. The IL-17A signal transduction triggers a 14-3-3ζ-TRAF5 dependent and a 14-3-3ζ-TRAF6 dependent intracellular pathway responsible for producing CXCL-1 and IL-6, respectively. Improved IL-17A signaling blockers are desirable in treating autoimmune diseases such as rheumatoid arthritis and lupus. Due to its unique role, 14-3-3ζ is an attractive target to regulate CXCL-1 and IL-6 levels. The aim of this study is to determine interaction sites between the 14-3-3ζ and TRAF (5 and 6) proteins using bioinformatic tools. We used 6EF5.pdb for 14-3-3ζ, 4GJH.pdb for TRAF5, and ILB6.pdb for TRAF6. Using ZDock, we examined the putative site of the 14-3-3ζ interactions on TRAF (5 and 6) with restrictions and without restrictions. The mapped interacting residues were mutated, and an effect on the interaction with 14-3-3ζ was observed. To further evaluate the interaction quality, we utilized Prodigy to measure the binding energy for several possible structures and narrow down the selected interaction sites further. Results indicate that site 479–485 is the putative target site of the 14-3-3ζ-TRAF5 complex with a ΔG of −10.1 kcal/mol and a Kd of 4.00×10−8. By comparison, residues 483–488 on TRAF6 interact with 14-3-3ζ with a ΔG of −19.1 kcal/mol and a Kd of 9.50×10−15. Our results demonstrate the putative binding sites between the 14-3-3ζ and TRAF (5 and 6) proteins. However, our study has the limitation of using the available but incomplete TRAF structures; therefore, lab studies should be used to confirm these results. Our results provide a rationale to investigate the 14-3-3ζ and TRAF proteins further.
A role of B-cells and antibodies in generation of protective immune responses against a vaccinating antigen during non-albicans Candida mediated systemic candidiasis
Authors: Rohatgi Soma , Shukla Manisha 
Published: February 2023

Abstract
While cellular immunity is acknowledged to be critical for vaccine-mediated protection during systemic candidiasis, the role of humoral immunity is not clear. We investigated the role of B cells and antibodies in conferring protective advantage during Candida tropicalis mediated murine systemic candidiasis, using a lead vaccine candidate, Sap2 (secreted aspartyl proteinase 2) obtained from C. parapsilosis. Compared to sham-immunized mice, Sap2-parapsilosis vaccinated mice exhibited significantly improved survival outcomes (p=0.02) and reduced organ fungal burdens (p&lt;0.05). Sap2-parapsilosis vaccination induced high titres of Sap2-specific antibodies, and a fraction of antibodies could bind whole fungus (of predominantly IgM isotype). Notably, sera from Sap2-parapsilosis-vaccinated mice exhibited increased C. tropicalis biofilm inhibition ability and enhanced neutrophil-mediated fungal killing in vitro. Sap2-specificity was further confirmed by depleting antigen-specific antibodies. Passive transfer of Sap2-parapsilosis immune serum significantly reduced fungal burdens in naive mice, as compared to mice receiving sham-immune serum, upon infection. Higher numbers of total CD19+ B cells, plasma cells and Candida-binding B cells in Sap2-vaccinated mice indicate towards a role of B cells during early stages of Sap2-mediated immune response. Epitope analysis performed using identified B cell epitopes provides insights about including important IgM and IgG epitopes, when designing multivalent or multiepitope anti-Candida vaccine/s. In summary, our results establishes a role of B cells and antibodies in contributing towards protective efficacy of Sap2 vaccine antigen during murine systemic candidiasis.
Metallothioneins reprograms T cell response towards pulmonary Histoplasma capsulatum through altering their metabolic profile
Authors: Alrefai Hani , Vignesh Kavitha Subramanian , Deepe George S 
Published: February 2023

Abstract
Histoplasma capsulatum (Hc) is a dimorphic fungus that is affected by environmental temperature. Hc is distributed worldwide. When inhaled, the microconidia and spores reach the lung and are converted to the pathogenic yeast phase within the phagosomes of macrophages. The Hc replicates intracellularly until these phagocytes are activated by cytokines, typically from activated T cells. Excluding iron, the effect of trace metals on Hc interaction with innate immune cells has been inadequately studied. The cells’ metabolic processes are altered, and the cytokine macro/microenvironment change in the pathogen’s face. Zn2+ metalloproteins constitute about 10% of the mammalian proteome, and many transcription factors and enzymes use this metal. Metalloproteins are linked to many energy-producing pathways, including carbohydrate metabolism, amino acid metabolism, and the redox chain. Our experiments showed that ablation of Metallothioneins 1 and 2 (MT1/2) decreases the immune system’s ability to clear Hc from the lungs. The numbers of T cells are not affected by the MT1/2 ablation; rather, the cells’ activity is decreased. MT1/2 ablated dendritic cells (DC) are not defective. MT1/2 ablated CD4 T cells show an alternative metabolic profile. MT1/2 ablated CD4 T cells show a decrease in their genome acetylation.
Pseudomonas aeruginosa Outer Membrane Vesicles (OMVs) Cause Inflammation and Cardiomyocyte Contractile Dysfunction
Authors: Rajaram Murugesan , Kumar Naresh , Pestrak Matthew Pestrak , Wu Qian , Nolan Sheri Dellos , Lafuse William , Ganesan Latha P. , Wozniak Daniel J. 
Published: February 2023

Abstract
P. aeruginosa (P.a) infection causes severe pneumonia, which can lead to cardiac inflammation and severe cardiac complication. Growing evidence indicates that cardiac resident macrophages are important regulators of inflammation and steady state heart function. On the other hand, pathogen secreted OMVs carry bacterial immunogens that activate the host immune system and alter the homeostasis of normal organ function. Our published results showed that P.a. infection causes cardiac inflammation, fibrosis, and cardiac dysfunction without the bacteria disseminating into heart tissue. However, the mechanism of P.a. induced cardiac inflammation and dysfunction is not known and understanding this is critical for the development of host directed therapy. Thus, we hypothesize that cardiac damage caused by P.a infection is mainly due to the release of bacterial toxins and/or OMVs or by inflammatory mediators released by immune cells. To test our hypothesis we have used human monocyte derived macrophages (hMDMs) and human induced pluripotent stem cell-derived cardiomyocytes (hiPSC-CMs). Our results show that conditioned media from P.a. infected hMDMs causes contractile dysfunction in hiPSC-CMs. In addition, we found that P.a. OMVs induce similar contractile dysfunction in hiPSC-CMs. Notably, we also found that OMV stimulation activates classical inflammatory signaling pathways and enhances hMDM inflammatory cytokine production. These findings demonstrated that P.a OMVs induce inflammatory cytokine production and subsequent myocyte contractile dysfunction. Studies are ongoing to determine the mechanism of OMV induced contractile dysfunction as well as the impact of OMVs on cardiac dysfunction in a mouse model.
Complement Receptor 3, but not Fcγ Receptor III, abolishes the intracellular survival advantage of virulent Rhodococcus equi in murine macrophages
Authors: Silveira Bibiana Petri da , Cohen Noah D. , Bray Jocelyne M. , Barhoumi Rola , Bordin Angela Ilha 
Published: February 2023

Abstract
Complement receptor 3 (CR3) and Fc gamma receptor III (FcγRIII) are proposed to be essential for mediating Rhodococcus equi entry and killing in macrophages, respectively. Our objective was to investigate the role of each of these receptors in phagocytosis and intracellular replication of R. equi by macrophages. Wild-type (WT), CR3−/−, and FcγRIII−/− J774A.1 macrophages were infected with either virulent or avirulent opsonized R. equi. Quantitative culture was performed immediately post-infection (T0) and after 48 h (T48). Data were analyzed using mixed-effects modeling with the following outcomes: 1) ratio of inoculum:T0 (phagocytosis); and, 2) ratio of T48:T0 (intracellular survival). Additionally, WT, CR3−/−, and FcγRIII−/− macrophages were infected with virulent or avirulent GFP+ R. equi to confirm intracellular infection by confocal microscopy. Our results demonstrate that phagocytosis of either virulent or avirulent R. equi was unaffected by knocking out CR3 or FcγRIII, and imaging revealed that CR3−/− and FcγRIII−/− internalized both R. equi strains similarly to WT macrophages. As expected, intracellular survival in WT was significantly higher for virulent than avirulent R. equi. In CR3−/−, however, no significant difference in survival between virulent and avirulent strains was observed. Knocking out FcγRIII did not alter R. equi intracellular replication. Our findings demonstrate that CR3 is not necessary for R. equi infection and show that CR3 deletion eliminated the intracellular survival advantage of virulent strains. Last, FcγRIII-mediated phagocytosis does not improve intracellular killing as previously suggested.
Microbiota regulate the induction and proliferation of revival intestinal stem cells through inflammatory cytokines
Authors: Tsang Derek K.L. , Wang Ryan J. , Maisonneuve Charles , Ayyaz Arshad , Trcka Daniel , Wana Jeffrey L. , Girardin Stephen E. , Philpott Dana J. 
Published: February 2023

Abstract
Gut microbiota are critical mediators of inflammation and regeneration of the intestinal epithelium. Intestinal restitution is a coordinated response that involves the dedifferentiation of mature epithelial cell lineages, the proliferation of Lgr5+ intestinal stem cells, and the induction of Clu+ revival stem cells (RSCs). How the gut microbiota directly impacts this regenerative process remains unclear. Using irradiation as a model for small intestinal epithelium restitution, we demonstrate that microbiota regulate the induction and subsequent proliferation of Clu+ RSCs. Our results report that specific pathogen-free (SPF) mice induce greater RSCs 3 days post-IR in comparison to germ-free (GF) mice. This microbiota-dependent increase in RSCs was matched by an increase in BrdU+ proliferating cells and an increase in TUNEL+ apoptotic cells in SPF mice. Using intestinal organoids as an in vitro model of intestinal restitution, SPF and GF intestinal crypts demonstrated equal propensity to generate mature organoids. Transcriptional analysis of GF and SPF RSCs by single-cell RNA sequencing highlighted unique regenerative and inflammatory gene signatures. The altered regeneration kinetics observed in SPF mice was accompanied by an increase in Tnfa and Cxcl1 at the peak of RSC induction and an increase in Ifnγ post RSC induction. Altogether, these findings suggest that microbiota-dependent expression of inflammatory cytokines may be key regulators in facilitating the expansion and proliferation of RSCs to efficiently repair the intestinal epithelium following damage.
Defective Humoral Immunity Disrupts Bile Acid Homeostasis Which Promotes Inflammatory Disease of the Small Bowel
Authors: Mohammed Ahmed Dawood , Kubinak Jason L. 
Published: February 2023

Abstract
Mucosal antibodies maintain gut homeostasis by promoting spatial segregation between host tissues and luminal microbes. Whether and how mucosal antibody responses influence gut health through modulation of microbiota composition is unclear. One critical metabolic function carried out exclusively by bacteria in the gut is bio-transformation of host bile acids (BAs), and dysregulation of BAs metabolism has been linked to numerous inflammatory and metabolic diseases in humans. Here, we use a CD19−/− mouse model of antibody-deficiency to demonstrate that a relationship exists between dysbiosis, defects in BA homeostasis, and enteropathy of the small intestine (SI). SI enteropathy that develops in CD19−/− mice is associated with alterations to the luminal BA pool in the SI, marked by significant reductions in the abundance of conjugated BAs. Manipulation of BA availability, adoptive transfer of functional B cells, and ablation of bacterial bile salt hydrolase (bsh) activity all influence the severity of SI enteropathy in CD19−/− mice. Collectively, results from our experiments support a model whereby mucosal humoral immune responses limit inflammatory disease of the small bowel by regulating bacterial BA metabolism.
Lack of bone marrow stromal cell antigen-1 (BST-1)/CD157 ameliorated colitis induced by dextran sodium sulfate (DSS)
Authors: Ishihara Katsuhiko , Yahagi Ayano , Katsumata Ryo , Shiotani Akiko , Iseki Masanori 
Published: February 2023

Abstract
Bone marrow stromal cell antigen-1(BST-1)/CD157 is GPI-anchored ectoenzyme having adenosine diphosphate(ADP)-ribosyl cyclase and cyclic ADP-ribose hydrolase activities. BST-1 also functions as a receptor for signal transduction. Recently, various groups reported novel functions of BST-1, such as regulation of intestinal or mesenchymal stem cells. Re-analyses of BST-1 deficient mice (Bst1KO) in C57BL/6 background revealed roles in defense against tuberculosis, and prevention of depressive or anxious behaviors. Thus, BST-1 is now appreciated as an entero-neuro-immune regulator. Since expression of BST-1 in the intestines is common in human and mouse, we examined the roles for BST-1 in DSS-induced colitis using Bst1KO.
Drinking water containing 3% DSS was supplied ad libitum to Bst1KO and C57BL/6 (WT) in SPF condition for 5 days, and then water without DSS for 2 days. Decreases of body weights in Bst1KO were similar to WT until day 5, but since then they became significantly slower than WT. Clinical scores based on bleeding and diarrhea were similar in both genotypes. Histological analyses with HE staining revealed the ratio of destroyed epitheliums in the total colon of Bst1KO was 15% whereas that of WT was 50%. Flow cytometrical analyses revealed no difference in the cell numbers of neutrophils and macrophages increased in the colon at day 7. Quantitative real-time PCR revealed that increases of Bst1 expression in the colons of WT started on day 1 and reached to the level more than thousand times at day 5. In the colons of Bst1KO, increases of Il6 expression at day 5 were markedly decreased compared with those of WT.
These data indicate that BST-1 has pro-inflammatory roles in DSS-induced colitis through positive regulation of IL-6 production.
Lymph node stromal cells drive MHCI-restricted CD8 T cell lineage plasticity
Authors: Honan Amanda , Vazquez Emily , Chen Zhibin 
Published: February 2023

Abstract
CD8+ T cells have been shown to convert to CD4+ T cells in the gut environment producing a unique population of MHCI-restricted CD4+ T cells. MHCI-restricted CD4+ T cells then have the ability to further differentiate into MHCI-restricted CD4+Foxp3+ T cells (CI-Treg). Here, we show several factors which facilitate the conversion from the CD8+ T celllineage to the CD4+ T cell lineage in the gut environment. Intrinsic MHCII expression by lymph node stromal cells (LNSC) is an important factor in this process. Both the conversion from CD8+ T cells to CD4+ T cells and the differentiation of CI-Treg are impaired when MHCII is deleted. Furthermore, in vitro co-culture experiments show that LNSC are vital in the expansion of both MHCI-restricted CD4+ T cells and CI-Treg. This population of regulatory T cells also exhibits an atypical phenotype which may contribute to the ability to control inflammation within the gut environment and beyond, and thus may add a new possibility to the arsenal of immune cell therapy for tolerance induction.
Evolution of immunogenetic components used to form ultralong VH CDR3 antibodies in Bovidae
Authors: Mitchell Christian D. , Marchand Ashley J , Head Kelly , Haakenson Jeremy K , Kelley Abigail , Deiss Thaddeus C , Derr James N , Smider Vaughn V , Criscitiello Michael F 
Published: February 2023

Abstract
Cattle has a restricted repository of immunoglobulin heavy chain gene segments with only one family of V, 4 J and 16 D segments functional. Among these segments are a V and D that, together, encode a heavy chain with an ultralong CDR3 region which manifests as a “stalk” supporting a “knob” domain of which only the knob has antigen binding capability. This antibody structure has boundless therapeutic potential, including for treatment of HIV and other antigens with veiled epitopes. Upon the discovery of this ultralong antibody in Bos taurus, speculation of its origin began. The components that should facilitate ultralong CDR3H antibodies appear in more species than just Bos taurus; they expand throughout the bovine subfamily as evidence by the presence of a V motif “TTVHQ” crested by an 8 base-pair (bp) duplication, and a comparatively long D segment. Several closely-related species encode the ultralong V segments gene in their germline IgH locus. Phylogenetically bookending the cluster that is genomically equipped for the ultralong cattlebody are the species Bos taurus and Bison bison with Bos mutus, indicus, and grunniens in between. The added length of the D segment is less consistent throughout the group as none of the species encode as long of segment as Bos taurus at 50 amino acids. Two species studied, Bos mutus and Bos grunniens, have 15 and 22 amino acids, respectively, encoded by their longest D segment, and Bison bison has 23. Though we do know the germline encodes the ultralong antibody, it is imperative to know if the gene rearrangement is actually expressed and employed in the mature repertoire.
SARS-CoV-2 spike binding peptides: A potential therapeutic approach for COVID-19
Authors: Ramasamy Santhamani , Zain Siddiqui , Roy Abhishek , Kumar Ranjeet , Kolloli Afsal , Chang Theresa Li-Yun , Kumar Vivek , Subbian Selvakumar 
Published: February 2023

Abstract
SARS-CoV-2, the causative agent of COVID-19, has infected about 100 million people and resulted in 2.6% mortality worldwide since late 2019. Various anti-viral agents, such as Remdesivir and hydroxychloroquine, have been used empirically to treat COVID-19. However, efficient therapeutics for COVID-19 are yet to be developed. SARS-CoV-2 enters the host cells by binding its envelope spike protein to the cellular receptors, like the ACE2. Here, we report the assessment of a panel of SARS-CoV-2 spike-binding synthetic, self-assembling peptides for their therapeutic potential. A HIV-1 pseudo typed virus (pNL-Luc.R-E-) expressing full-length SARS-CoV-2 spike protein was used to evaluate the anti-viral effect of these peptides. Briefly, pseudoviruses were treated with nine peptides at 0.01μM, 0.1μM, 1μM, 10μM concentrations before infecting 293T cells overexpressing ACE2. Viral infection was determined by measuring the luciferase activity of the infected cells. The anti-SARS-CoV2 activity of tested peptides was also evaluated by plaque-forming assay using replication-competent viruses. All the tested peptides showed SARS-CoV-2 neutralization, and five of the nine peptides showed IC50 values ≤ 0.01μM. In a rat model, we showed that the peptides, administered at 1mM daily-dosing for 10 days, was non-toxic and well-tolerated, indicating their potential therapeutic use for COVID-19. Further study warrants in vivo efficacy testing of selected peptides in preclinical animal models.
DEC-205 is essential for control of WNV infection and immunity in the CNS during WNV encephalitis
Authors: Ho Justin , Khatri Hemisha , Santana Anthony , Durrant Douglas 
Published: February 2023

Abstract
West Nile Virus (WNV) is the leading cause of mosquito-borne neuroinvasive disease in the United States. Upon entry into the central nervous system (CNS), WNV infects neurons, causing neuronal injury and inflammation, potentially resulting in long-term sequelae and death. Studies have shown that infiltrating virus-specific CD8+ T cells are dependent on dendritic cell-mediated reactivation in the CNS to restrict viral replication and pathogenesis within the CNS. Previous reports have shown that CD8+DEC-205+ dendritic cells (DCs) rapidly accumulate within the CNS during WNV encephalitis; however, their specific role in host defense has not been demonstrated. DEC-205, an endocytic receptor expressed by DC subsets, is responsible for cross-presentation and can promote either antigen (Ag) specific effector T cell activation or immunological T cell tolerance. Using a mouse model of WNV encephalitis, we show that DEC-205 critically regulates effector T cell responses within the CNS. DEC-205−/− mice exhibited enhanced mortality compared to wild-type (WT) controls. The enhanced susceptibility of the DEC-205−/− mice arose from an increased viral burden; however, this was associated with increased numbers of infiltrating and activated T cells and increased inflammatory myeloid cells suggesting that DEC-205 promotes protective immune responses within the CNS that limit immunopathology during a neurotropic viral infection. These data clarify the role of DEC-205+ DCs in the restriction of viral pathogenesis and implicate DEC-205+ DCs as a key regulator of protective immune responses within the CNS.