bluuebunny/crossref_metadata_2025_split huggingface dataset:
Unique properties of GC B cells permit optimal BCR affinity discrimination
Authors: Kwak Kihyuck , Quizon Nicholas , Sohn Haewon , Manzella-Lapeira Javier , Spillane Katelyn , Holla Prasida , Lu Jinghua , Tolar Pavel , Pierce Susan K. 
Published: January 2023

Abstract
Upon encountering pathogens, B cells within lymphoid organs enter specialized micro-environments of germinal centers (GCs). In the dark zones (DZ) of GCs, B cells proliferate and undergo somatic hypermutation, and subsequently migrate to the light zone (LZ) of the GC where selection of B cells that express the highest affinity B cell receptors (BCRs) occurs. Affinity selection is driven by the ability of BCRs to signal and extract antigen from the surfaces of follicular dendritic cells. Here we provide evidence that human tonsil LZ GC B cells are inherently better able to undergo affinity selection as compared to naïve tonsil B cells. LZ GC B cells engaged membranes that contained F(ab’)2 anti-light chain as a surrogate antigen through highly dynamic F-actin-containing pod-like structures that concentrated BCRs at their contact points. Using DNA-based mechanical force nano-sensors we observed robust pulling forces localized to the contact sites of the pods with the membrane. In contrast naïve B cells formed flat stable contacts with the membranes and showed only defuse weak pulling forces. Using antikappa antibodies of low (KD=3.9×10−7) versus high (KD=2.4×10−9) affinities as surrogate antigens, we show that LZ GC B cells were able to discriminate between these and responded only to the high affinity antigen. In contrast, naïve B cells responded equally to both antigens. Both LZ GC B cells and naive B cells were able to extract and internalize membrane-bound antigen, however, only in LZ GC B cells was the subsequent trafficking of the antigen to acidic intracellular compartments for processing highly dependent on the amount of antigen internalized. Thus, LZ GC B cells appear to be intrinsically programmed for optimal affinity selection.
TLR/BCR co-engagement induces mature and protective T-cell independent antibody responses through MyD88 and PI(3)K signalings
Authors: Rivera Carlos Eduardo , Xu Zhenming , Casali Paolo 
Published: January 2023

Abstract
B cells are central to immune responses to infections and vaccines by producing high-affinity and class-switched protective antibodies, often in a T cell-dependent manner. Prompted by our findings that dual TLR/BCR engagement induces efficient CSR in vitro, to a high level comparable to that induced by CD40 engagement, here we have analyzed induction of T cell-independent CSR/SHM and antibody responses by TLR-BCR co-engagement. Immunization of wildtype C57 mice with NP hapten conjugated to TLR4-engaging LPS (NP-LPS), but not NP-Ficoll admixed with LPS, elicits high-affinity and class-switched IgGs (IgG1, IgG2a, IgG2b, IgG3), at levels comparable to those elicited by a T cell-dependent antigen NP-CGG. NP-LPS also induces sustained and high levels of IgG2a, IgG2b and IgG3, but not IgG1, in Tcrβ−/−Tcrδ−/− mice, which are devoid of T cells and, as expected, fail to mount any response to NP-CGG. Immunization of both wildtype and Tcrβ−/−Tcrδ−/− mice with highly purified Salmonella typhimurium (S. typhimurium) flagellin, which has dual BCR and TLR5 engaging activities, elicits flagellin-specific antibodies that can opsonize S. typhimurium. T cell-independent immune responses, which are impaired in mice lacking Myd88 or Pik3r1 in B cells, are associated with high mutation loads in VH genes, generation of switched B cells, and B cell differentiation into long-lived plasma cells and memory B cells, which can be re-activated for anamnestic antibody responses. Thus, SHM/CSR and B cell differentiation into plasma cells and memory B cells can occur independently of T cells, leading to protective mature antibody responses.
Toll-like receptor 9 signaling antagonizes antigen-specific B cell-helper T cell interactions
Authors: Akkaya Munir , Akkaya Billur , Kim Ann S , Miozzo Pietro , Sohn Haewon , Pena Mirna , Skinner Jeff , Kabat Juraj , Pierce Susan K 
Published: January 2023

Abstract
Key events in T cell-dependent antibody responses are dependent on the ability of B cells to capture antigen and process and present it to follicular helper T cells. Despite its importance, little is known about the regulation of this critical B cell function. Here we focus on the impact of signaling through the innate immune receptor, Toll like receptor 9 (TLR9), on the outcome of a B cell’s encounter with antigen. We show that although TLR9 signaling induced B cell proliferation, and secretion of cytokines and IgM, it blocked the ability of antigen-specific B cells to capture, process and present antigen. In the presence of the TLR9 agonist, CpG, B cells were less able to form synapses with antigen-containing membranes and to pull antigen from them. CpG also diminished the ability of the BCR to traffick antigen within the cell to antigen processing compartments resulting in fewer MHC-peptide complexes on the B cell surface. TLR signaling also antagonized the BCR-induced increases in the expression of both MHC class II and important co-receptors, including CD86, resulting in a decrease in the duration of antigen-specific B cell-T helper cell interaction and the inability of B cells to activate antigen-specific T cells. Chimeric mice that contained either wild type B cells or B cells deficient in TLR signaling when immunized with antigen adjuvanted with CpG showed that the loss of the B cells’ ability to respond to CpG resulted in lower antigen-specific IgM responses but enhanced high affinity antigen-specific IgG responses. Thus, B cell intrinsic TLR9 signaling may ensure rapid B cell expansion and antibody secretion at the expense of the ability of B cells to engage in germinal center events that are highly dependent antigen capture and presentation.
Dynamic regulation of T Follicular Regulatory (Tfr) cell responses by Interleukin-2 (IL-2) during influenza infection
Authors: Ballesteros-Tato Andre , Botta Davide , Fuller Michael J , Bachus Holly , Bradley John E , Zajac Allan J , Randall Troy D , Lund Frances E , Ruiz Beatriz León 
Published: January 2023

Abstract
IL-2 promotes FoxP3+ regulatory T (Treg) cell responses, but inhibits the differentiation of T follicular helper (Tfh) cells. However, it is not clear how IL-2 affects T follicular regulatory (Tfr) cells, a cell type with properties of both Treg and Tfh cells. Here we show that IL-2 prevents, rather than promotes, the development of Tfr cells. Using an influenza infection model, we found that Tfr cells were barely detectable at the peak of the infection, but accumulated as the immune response resolved. High levels of IL-2 at the peak of the infection promoted the expression of Blimp-1 in Treg cells, which suppressed Bcl6 expression and thereby precluded Tfr cell development. However, as IL-2 levels declined some CD25+ Treg cells down-regulated CD25, up-regulated Bcl6 and differentiated into Tfr cells, which prevented the accumulation of self-reactive antibody-secreting cells. Thus, unlike its effects on conventional Treg cells, IL-2 inhibits Tfr cell responses.
The RNA transcriptome of in vivo influenza virus infection reveals unique gene expression profiles in type 2 alveolar epithelial cells.
Authors: Stairiker Christopher , Hancock Aidan S , Boesteanu Alina C , Monzon-Casanova Elisa , Lukasiak Sebastian , Stubbs Andrew , Turner Martin John Charles , Katsikis Peter D 
Published: January 2023

Abstract
Globally, influenza virus outbreaks represent a serious threat to public health. Influenza virus infects type 2 alveolar epithelial cells (AEC) and utilizes cellular machinery in order to produce new infectious virions. During infection, multiple cell types release cytokines and other soluble factors that influence gene expression in both infected and uninfected cells. Here, the unique in vivo gene expression profiles between infected and uninfected bystander AEC from influenza virus infected mice are compared via next generation RNA-sequencing analysis. Mice were infected with PR8-expressing GFP virus (PR8-GFP). On day 3 post infection, GFP positive and negative AEC were FACS sorted from influenza virus infected mouse lungs. Transcriptome next generation RNA-sequencing analysis was performed comparing influenza-infected GFP-positive cells versus uninfected bystander GFP-negative cells from influenza virus-infected mouse lungs. Results from the sequencing data suggest a number of genes and associated pathways that are significantly differentially expressed in GFP-positive versus GFP-negative AEC. Pathways such as interferon signaling and cell death were found to be increased while Wnt signaling was decreased specifically within GFP-positive infected cells. RNA sequencing also identifies unique genes that are upregulated during virus infection, such as heatr9, that have yet to characterized during the response to influenza.
Sterile-activated cDC1 cells in neonatal lung induce T cell IL-4 production and lymph node maturation
Authors: Silva-Sanchez Aaron , Meza-Perez Selene , Stone Sara L , Randall Troy 
Published: January 2023

Abstract
Neonates are susceptible to respiratory tract infections, possibly due to immature pulmonary dendritic cells (cDCs). Here we assessed the development and function of conventional DCs in the lung and the lung-draining mediastinal lymph node (MedLN). We found that neonatal lungs, from days 3 to 10 of life, contained a higher proportion of CD103+ cDC1 cells than adult lungs and that these cells could be divided into a small population of CD103hi cDC1 and a larger population of CD103int cDC1, which were not found in adult lungs. A similar expansion of cDC1 cells was observed in the MedLN migratory cDCs during the first 2 weeks after birth. Transcriptional and functional assays showed that neonatal CD103int cDC1 cells had an activated phenotype and efficiently migrated to the MedLN, their formation was dependent on the transcription factor Batf3 but CD103int cDC1 cells developed independently of the microbiota or MyD88 signaling. Neonatal cDC1 cells express high levels of OX-40L and produce IL-12p40, but not IL-12p70, and stimulated the differentiation of IL-4-producing OT-II cells. Importantly, the MedLNs of neonatal Batf3−/− had poorly developed HEVs and FRCs, which were restored by transfer of neonatal lung CD103int into Batf3−/− mice. These changes were not observed following transfer of CD103hi or CCR7−/− CD103int DCs. Overall our results indicate that neonatal lung CD103int cDCs are activated as part of a developmental program that promotes MedLN maturation and biases CD4 T cell activation towards IL-4 production.
Gp120 transgenic mice infected with LP-BM5 virus show exacerbated symptoms compared to LP-BM5 murine AIDS alone
Authors: Arabatzis Taxiarhia J , Wakley Alexa A , McLane Virginia D , Rau Sanjay , Cao Ling 
Published: January 2023

Abstract
It is estimated that 36.7million people live with HIV/AIDS globally, and nearly half of them suffer from HIV associated neurocognitive disorder (HAND). The LP-BM5 virus murine AIDS (MAIDs) model and HIV gp120 transgenic (tg) mice are two distinct and well characterized models for investigating the pathophysiology of HIV/AIDS in mice. The LP-BM5 virus does not contain any HIV viral components, while gp120tg mice develop only CNS-related pathology without brain region differences. To generate a more clinically relevant murine HAND model, we examined the progression of LP-BM5 infection in gp120tg mice. Gp120tg (+) mice showed an exacerbation of the disease following infection when compared to their gp120tg (−) littermate controls and wild type (WT) C57BL/6 controls. At 12 wks post infection, all infected mice showed splenomegaly, and infected gp120tg (+) mice had higher IgG2a serum levels and an increased viral burden in hippocampi compared to the gp120tg (−) and WT controls. CCL5 expression in the hippocampus and striatum was also increased in all infected mice, with gp120 (+) mice showing the greatest elevation of hippocampal CCL5 expression. Interestingly, LP-BM5 appeared to induce brain region-dependent changes in type I interferons in gp120tg (+) mice. In addition, infected gp120tg (+) mice trended towards more errors in the spontaneous alternation T-maze test suggesting an association between a higher viral load in the hippocampus and greater memory and learning deficits. These results suggest that gp120tg mice can be productively infected with the LP-BM5 virus and display more severe MAIDS and HAND associated changes, representing a clinically relevant HAND model.
Isolation and characterization of a novel bacteriophage SH1 and optimizing PFGE to determine the molecular weight of SH1 bacteriophage’s DNA
Authors: Hoda Smriti , Greguske Elizabeth 
Published: January 2023

Abstract
Discovery of antibiotics has revolutionized the 20th century medicine, and has been one of the most potent methods to treat bacterial infections. Before antibiotics, infectious disease was the number one killer worldwide, in fact, bacterial infections killed more people than World War I. Hence, it took the world by a storm when certain bacteria started to develop their own defense in their war against antibiotics. Through a phenomenon called antibiotic resistance many bacteria commonly known as “superbugs” are able to overcome the treatment, and still can pose a threat to humanity.
Dr. Greguske’s research team at Saint Anselm College are turning to a novel approach of phage therapy to combat these lethal infections. The aim of the lab is to study the host-pathogen interface pathogenesis in order to utilize that mechanism the virus uses to specifically target and kill the bacteria, to ultimately treat the bacterial infection.
We isolated, purified, and conducted a biostability test of the newly found bacteriophage from the environmental sample. We extracted the phage’s DNA and optimized a protocol so that Pulse Field Gel Electrophoresis (PFGE) can be used to determine the bacteriophage DNA’s molecular weight. Upon doing so, we also have registered the phage into the virus database as SH1, and our next step is to get the bacteriophages’ genome sequenced at Dartmouth College, cross examine the database for the phage, and annotate its genome.
Intravenous immunoglobulin G (IVIg) concurrently promotes Th2 and T regulatory cell development while abrogating Th17 cells
Authors: Dembele Marieme , Tao Shao , Xue Di , Kaufman Gabriel Nathan , Mendonca Laura , Divangahi Maziar , Mazer Bruce David 
Published: January 2023

Abstract
We aimed to further elucidate the mechanisms by which IVIg modulates the balance between Th17, Th2, and Treg.
Using an OVA-driven murine model of allergic airway disease exhibiting a mixed Th17/Th2 response, we examined lung inflammation by H & E staining and histology, and performed cellular phenotyping of lung homogenates using flow cytometry. In addition, we assessed cytokine production by intracellular staining and ELISA, and performed co-culture studies.
IVIg treatment reduced lung inflammation and diminished the frequency and absolute number of lung Th17 cells, IL-17A production, and neutrophilia. In contrast, the frequency and absolute number of eosinophils and basophils was increased, while IgE production was abrogated in the IVIg group. This was accompanied by a significant increase in IL-13+ and IL-5+ T cells and in IL-5 concentration in the BAL. The frequency of Foxp3+IL10+ + cells within CD4+ T cells (1.43 % ± .061 vs 2.57 % ± .30, p &lt; .01) and IL-10 secreting dendritic cells (0.28 % ± 0.060 vs 1.20 % ± 0.27, p &lt; .05) was augmented. We also observed an increase in the frequency of CD206 expressing macrophages, or M2 macrophages, in the IVIg group (10.81% ± 2.21 vs 19.80 % ± 1.81, p &lt; .01).
Using an in vitro DC: T cell co-culture, IVIg-treated DC inhibited IL-17A production by T cells and increased IL-13 production and Treg differentiation.
In conclusion, IVIg modulates Th2/Th17/Treg balance by favoring Treg and Th2 cells while inhibiting Th17 cells. Furthermore, IVIg renders both dendritic cells and macrophages tolerogenic.
Vitamin D supplementation modulates Th2 immune response by inducing T regulatory cells in allergic conjunctivitis
Authors: Lee Hyun Soo , Kwon Ji Young , Joo Choun-Ki 
Published: January 2023

Abstract
Allergic conjunctivitis (AC) is one of the most common diseases encountered in eye clinics. Recently, Vitamin D deficiency has been shown to be associated with allergic AC. This present study was designed to evaluate the efficacy of vitamin D to suppress ovalbumin (OVA)-sensitized AC in a murine model. BALB/c mice were sensitized with OVA and aluminum hydroxide. Two weeks later, mice were challenged by OVA eyedrops for 12 days with intraperitoneal injection of vehicle or 1,25(OH)2D3. We evaluated clinical signs, the infiltration of inflammatory cells, regulatory T cells (Treg), serum IgE, and Th2 cytokines through flow cytometry and ELISA. In addition, to evaluate inhibitory function of Treg cells, anti–CD25 blocking antibody or isotype control antibody was injected intravenously during topical OVA challenge. AC development and conjunctival infiltration of eosinophils and mast cells were significantly impaired with 1,25(OH)2D3 treatment. In addition, 1,25(OH)2D3 suppressed production of OVA-specific IgE in serum and Th2 cytokines in vitro T cell assays, such as IL-4 and IL-13, compared to vehicle group. Interestingly, 1,25(OH)2D3 led to increase Treg cells population in draining LNs and suppressive levels of clinical signs and inflammatory cells infiltration into conjunctivae were reversed by depleting Treg cells. Our results suggest that vitamin D supplement alleviate allergic conjunctivitis, indicated by suppressing Th2 response in draining LNs and inflammatory cells infiltration into conjunctiva through increasing population of Treg cells in draining LNs. Therefore our results demonstrated the therapeutic potential of vitamin D for allergic diseases including asthma or atopic dermatitis.
Diagnosis of red meat allergy with antigen-specific IgE tests in serum
Authors: Brestoff Jonathan R , Zaydman Mark A. , Scott Mitchell G. , Gronowski Ann M. 
Published: January 2023

Abstract
Red meat allergy is a tick-associated hypersensitivity reaction to galactose-α-1,3-galactose (α-gal) and is characterized by anaphylaxis, angioedema, urticaria and/or gastrointestinal symptoms occurring 3–6 hours after ingesting red meat such as beef, pork, or lamb. Diagnosis of red meat allergy is challenging due to the unusually long delay in symptom onset and poor sensitivity of skin prick tests with commercial meat extracts. The primary diagnostic tools available for this disease are quantification of α-gal-, beef-, pork-, and/or lamb-specific IgE in serum, however the diagnostic performance of these tests has not been reported. Using patient data for n=135 patients with red meat allergy and n=37 controls, we found that measurement of α-gal-specific IgE using the bovine thyroglobulin (bTG) ImmunoCAP method had the best overall sensitivity (100%) and specificity (92.3%) for diagnosis of red meat allergy. Measuring α-gal-specific IgE using the streptavidin (SA)-CAP technique or beef- or pork-specific IgE using ImmunoCAP were also effective tests with high sensitivities (89–92%) and variable specificities (65–82%). Lamb-specific IgE and total IgE had essentially no diagnostic value for red meat allergy. Positive and negative predictive values mirrored these trends. Taken together, these findings indicate that the α-gal-specific IgE test by bTG ImmunoCAP is the most useful for establishing a diagnosis of red meat allergy, although α-gal-specific IgE by SA-CAP and beef- and pork-specific IgE by ImmunoCAP are also effective tests.
RNA binding protein HuR is required for robust antigen-mediated CD4+ T cell allergic airway inflammation
Authors: Atasoy Ulus , Ellis Jason S , Techisintana Patsharaporn , Glascock Jacqueline , Ridenhour Suzanne 
Published: January 2023

Abstract
RNA binding protein HuR (ELAVL1) controls helper T cell differentiation by modulating the stability of multiple target mRNAs through interactions with 3′ UTR AU-rich elements. We hypothesized that HuR regulates antigen induced T cell activation and initiation of Th2 driven allergic airway inflammation. HuR was conditionally ablated in developing T cells prior to thymic egress (distal Lck-Cre ROSA HuRfl/fl mouse). Upon in vitro activation, YFP+ (HuR KO) T cells produced significantly less IL-4, IL-5, and IL-13 than control cells and considerably more IL-2. We also observed reductions in Gata-3, IL-4 and IL-2Rα (CD25) nascent transcription. The OVA challenge model of airway inflammation was used to ascertain the effects of HuR KO in vivo. While only 50% of CD4+ T cells in HuR KO mice lack HuR, there was total suppression of Th2 responses and these mice had complete amelioration of lung inflammation. Lung infiltrating CD4+ T cells had reductions in IL-2 and CD25 expression, and OVA challenged HuR KO mice had significantly reduced BAL IL-13. In parallel, mice were immunized with either OVA or KLH, boosted 10 days later, and antigen specific proliferative responses measured in vitro to investigate antigen-specific T cell responses in the absence of HuR. HuR KO T cells had profound proliferation defects compared to controls, and CD3/CD28 stimulation only partially restored proliferation defects. HuR KO T cells had reductions in STAT5/STAT6 signaling, pathways which are key for Th2 differentiation and function. We conclude HuR plays an indispensable role in regulating antigen specific allergic airway inflammation and Th2 differentiation.
EMPD-specific chimeric antigen receptor mediates T cell cytotoxicity to B cells expressing membrane IgE
Authors: Ma Zhengyu (Mark) , Fay Brittany F 
Published: January 2023

Abstract
IgE is the key mediator of allergic immune responses. Targeting the source of IgE, the IgE-expressing B cells, using adoptive T cell therapy (ACT) represents an attractive therapeutic approach for severe allergic diseases such as severe allergic asthma. To develop ACT for allergy, we designed chimeric antigen receptors (CARs) that recognize the extracellular membrane-proximal domain (EMPD) of membrane IgE (mIgE). EMPD serves as an ideal marker for IgE-expressing B ells since it exists only on mIgE but not on secreted IgE, and all IgE-expressing B cells express mIgE, although at varying levels. To construct EMPD-specific CARs, variable regions of four EMPD-specific monoclonal antibodies were cloned to assemble single chain variable fragments (scFvs) for EMPD binding. EMPC-specific CARs were efficiently expressed on the surface of primary human T cells. One of the CARs, 2E3E10, mediated potent cytotoxicity and INFγ production in response to U266 cells and Daudi cells expressing mIgE. The responses to U266 cells are especially encouraging since the cells express very low levels of mIgE. Our study demonstrates the proof of concept for using T cells expressing EMPD-specific CARs to eliminate IgE-expressing B cells. The rapid advances in the efficacy and safety of ACT should facilitate the development of CAR T cell immunotherapy for severe allergic diseases. Taking advantage of the ability of CAR T cells to persist and continuously eliminate IgE-expressing B cells, the approach may relieve symptoms for an extended period of time with a single treatment.