bluuebunny/crossref_metadata_2025 huggingface dataset:
Intrahepatic Vα14iNKT cells Promote Liver Pathology during Adenovirus infection by Regulating Hepatic CCL5 and Intrahepatic γδT cell Activation: Implications for Vaccine Development (89.2)
Authors: Ajuebor Maureen , Chen Qingling
Published: January 2023

Replication-defective recombinant Adenoviruses are potential innovative viral vaccine vectors for treating many inherited and acquired human diseases. Broad clinical application of Adenoviruses in vaccine development is being hindered by the induction of vigorous innate and adaptive immune responses against the vector resulting in loss of Adenovirus transgene and deleterious effects in the liver. Vα14iNKT cells are thymic-derived innate T cells at the interface between the two arms of the immune response. The pathophysiological role of Vα14iNKT cells during replication-defective Adenovirus infection is not known, and is therefore a focus of our study. Our results revealed that Vα14iNKT cells were activated in response to Adenovirus infection to produce hepatic CCL5. In vivo studies utilizing CCL5 deficient mice showed that CCL5 deficiency caused reduced liver pathology and Adenovirus transgene loss. Similar results were also seen after blocking the biological effects of CCL5 receptors. Additionally, our data also revealed a novel and previously unrecognized pro-inflammatory role for activated intrahepatic Vα14iNKT cells in promoting liver pathology by positively regulating intrahepatic γδT cell activation. In summary, we have identified a novel and important pro-inflammatory role for activated intrahepatic Vα14iNKT cells in positively regulating both hepatic CCL5 and activated intrahepatic γδT cells to induce liver pathology without loss of Adenovirus transgene.
A protein superantigen, Staphylococcal Enterotoxin B (SEB), directly activates invariant Natural Killer T cells and leads to Acute Lung Injury and Acute Respiratory Distress Syndrome (ARDS) (89.37)
Authors: Rieder Sadiye , Nagarkatti Prakash , Nagarkatti Mitzi
Published: January 2023

Invariant Natural Killer T (iNK T) express T and NK cell markers and secrete a variety of pro- and anti-inflammatory cytokines. Glycolipids such as alpha-galactosylceramide (α-GalCer) are potent activators of iNK T cells when presented by the antigen presenting molecule, CD1d. In this study, we investigated a novel protein antigen, SEB, for the activation of iNK T cells, using ARDS model in mice. In general, SEB activates T cells that posses T cell receptors (TCR) with Vβ8, -7 or -2 chains, and since iNK T cells also have this particular TCR, we hypothesized that SEB can directly activate iNK T cells. We demonstrate that after intranasal administration of SEB, vascular leak and infiltration of lymphocytes were significantly reduced in the lungs of Jα18-/- and CD1d-/- mice as compared to WT mice. The pore size in the endothelial cells of the capillaries of the lung was greater than 500nm for WT mice, while it was between 100 and 500nm for Jα18-/- and Cd1d-/- mice. We also show that cytokine storm induced by SEB was significantly reduced in the serum and bronchialveolar fluid of Jα18-/- and CD1d-/- mice. In vitro cultures that contained SEB-pulsed bone marrow derived dendritic cells (BMDCs) and FACS purified iNK T cells produced significant amounts of IFN-γ and IL-4, comparable to the α-GalCer-pulsed BMDC and iNK T cell cultures. We show for the first time that iNK T cells are activated by a protein antigen, and they are innate responders in Acute Respiratory Distress Syndrome.
The connection between Serum Amyloid P/Pentraxin-2 and IL-10 in the treatment of kidney fibrosis (89.43)
Authors: Castano Ana , Lupher Jr Mark , Duffield Jeremy
Published: January 2023

In models of kidney fibrosis, systemic administration of Serum amyloid P or Pentraxin-2 (PTX-2) significantly inhibits fibrosis through a monocyte/macrophage-dependent mechanism, and as such represents a potential novel therapy for the treatment of chronic inflammation with fibrosis. In transgenic Coll-GFP reporter mice, PTX-2 inhibited myofibroblast synthesis of collagen, but myofibroblast numbers were unaffected. PTX-2 is deposited on injured tissue and debris in the kidney, and is detected in endosomes/phagosomes of macrophages (Mϕs). It does not bind to, or inhibit collagen production by, fibroblasts in vitro, but it binds with high affinity to activating Fcγ receptors on monocytes/ Mϕs. Purified Mϕs from fibrotic kidney are less activated and produce 20 fold more IL10 in mice treated with PTX-2. To test the direct role of IL10 in the inhibition of fibrosis mediated by PTX-2, we systemically administered IL10 producing adenovirus (Ad-IL10 and control virus (Ad-mock) in models of kidney fibrosis. Ad-IL10 resulted in high levels of systemic IL10 and markedly attenuated fibrosis accumulation in the kidney. Systemic IL10 inhibited both monocyte/ Mϕ activation and myofibroblast proliferation and activation in vivo. We propose that the major mechanism of action of PTX-2 is to switch M2 or wound healing Mϕs into regulatory Mϕs. Local generation of IL10 blocks Mϕs driven fibrosis and directly inhibits myofibroblasts.
Characterization of the therapeutic increases in natural killer (NK) activity of xenotropic murine leukemia virus-related virus (XMRV)-positive chronic fatigue syndrome (CFS) patients effected by poly (I): poly (C12U) (Ampligen) (89.49)
Authors: Silvestre Isabel , Marshall Maria , Hagen Kathryn , Pfost Max , Strayer David , Peterson Daniel , Hudig Dorothy , Mikovits Judy
Published: January 2023

Chronic Fatigue Syndrome (CFS) is a debilitating disease of unknown etiology that affects ~17 million people worldwide. Patients suffer persistent viral infections and may develop hematopoietic malignancies. The patients have reduced Natural Killer (NK) cell activities which could contribute to the diseases, and, if restored, potentially reduce symptoms. We characterized the in vitro effects on NK cells of the interferon inducer poly (I): poly (C12U) (Ampligen) which in some CFS patients abates disease symptoms. The 30 CFS patients were infected with the gammaretrovirus xenotropic murine leukemia virus-related virus (XMRV). We cultured their peripheral blood mononuclear cells with the drug for 24 hrs and monitor NK activity to K562 cells by flow cytometry, concurrently measuring degranulation by externalization of CD107a, and expression of Grz B and perforin. Treatment markedly increased CD107a externalization in the NK cell population as indicated by 5-fold increases in CD107a-positive cell frequencies and 3-fold increases in their CD107a MFI, with slight positive shifts in intracellular Grz B and perforin. In contrast, T cells showed little change in CD107a externalization. Our results suggest that degranulation rates may be more affected than the levels of cytotoxic proteins, indicating a novel mechanism by which NK activity was affected by the drug. The increase in degranulation per NK cell indicates a mechanism by which Ampligen treatment can improve NK cell function.
Immunoregulatory Activities of Self-Nanoparticle Forming CpG ODN (89.52)
Authors: Gursel Ihsan , Tincer Gizem , Karatepe Kutay , Gursel Mayda
Published: January 2023

CpG ODN patterned after bacterial DNA can be harnessed in different clinical settings to provide an advantage to host. Several challenges hampers utilization of synthetic ODNs in the clinic. There are at least three distinct classes of CpGODNs displaying differential immune activation. Of note, the efficacy of these synthetic ODNs is reduced under physiological conditions due to premature clearance, nuclease digestion and low levels of internalization. Moreover, D-ODN as one of the most potent IFNα inducer has a large-scale production problem due to 3’polyG-runs hampering its entry into clinics. A novel class of ODN (NP-ODN420) devoid of polyGs that can undergo nanoparticle formation necessary for its IFNα induction is designed. Ex vivo stimulation of mouse splenocytes and in vivo administration of NP-ODN420 have revealed that it exhibits higher immunostimulatory potential due to higher internalization and nuclease resistance. The PO backbone is at least as potent as its more stable counterpart with the modified PS backbone. Furthermore, it combines superior properties of conventional classes of K and D-ODNs. These results have been reproduced in human peripheral blood mononuclear cells by various assays. NP-ODN420 induced significantly higher level of Th1-mediated anti-Ova response than conventional ODNs. In the tumor xenograft model, it promoted partial remission of the tumors. This knowledge will pave the way for more effective immunotherapeutic approaches.
Cigarette smoke modulates release of CXCL8 through the inflammasome signaling in human bronchial epithelial cells (16HBE14o) (89.57)
Authors: Mortaz Esmaeil , Kraneveld Aletta , Nijkamp Frans , Folkerts Gert
Published: January 2023

Chronic obstructive pulmonary disease (COPD) is a major health problem and cigarette smoke (CS) is the main risk factor for the development of COPD. Exposure to cigarette smoke activates inflammatory cells for production of CXCL8 with accompanying damage to the lung epithelium and recruitment of macrophages and neutrophils. The Inflammasome is a multiprotein complex consisting of caspase-1, and NALP molecules and promotes the maturation of inflammatory cytokines such as interleukin 1-β and IL-18. The role of IL-1β in induction of CXCL8 has been reported. The epithelium is a barrier to the entry of pathogens, and as a dynamic system for host response. The epithelium can produce natural antimicrobial factors and release pro-inflammatory cytokines. Therefore it is thought that the airway epithelium plays a role in modulating innate immunity. In this study we studied the effects of CS on the regulation of CXCL8 release via inflammasome signaling by HBE-14o cell lines. We found that in HBE-14o preincubation with anti-caspase-1 (Z-VAD-FMK) suppressed the release of CXCL8 induced by CSE. Moreover, CSE induced maturation of IL-1β (17 KD) and activates NALP3 molecules which is demonstrated by Western blotting. In conclusion this study indicates that inflammasome signaling may directly or indirectly promote the production of CXCL8 by human bronchial epithelial cells.
Stat3 and Th17-mediated colitis promotes regional tumorigenesis in response to a common commensal bacterium: role of Foxp3+ Treg/Th17 balance (90.17)
Authors: Geis Abby , Wolfe Jamie , Wu Shaoguang , Wu Xinqun , Pardoll Drew , Sears Cynthia , Housseau Franck
Published: January 2023

Enterotoxigenic Bacteroides fragilis (ETBF) is an inducer of inflammatory diarrheal disease with acute colitis, and may even be linked to chronic colitis and colorectal cancer in humans. The pathogenesis of ETBF can largely be attributed to the secretion of a toxin, BFT (B. fragilis toxin), which has a profound effect on the colonic microenvironment. BFT promotes cleavage of E-cadherin, activates NF-kB and Wnt/b-catenin signaling, and stimulates the secretion of pro-inflammatory cytokines, such as IL-6, IL-8, and TNF-a. The inflammation associated with ETBF is characterized by widespread colonic Stat3 activation and IL-17 cytokine secretion. In Min mice, the Th17-mediated inflammation promotes the formation of distal colon tumors, as demonstrated by reduced tumorigenesis in response to IL-17 blockade. Our research has been focused on elucidating the immunologic differences between the distal and proximal colon in an attempt to determine why tumorigenesis is so regional. We have found that the proximal colon has a greater density of Foxp3+ Tregs than the distal colon. Furthermore, preliminary data suggests that the Th17 cytokines are differentially expressed in the two regions. We propose that increased Treg density in the proximal colon restrains Th17-mediated inflammation relative to the distal colon. We are currently studying the relationship between the Treg cells and infiltrating effector cells and how that affects tumorigenesis in response to ETBF.
Identification, phenotype, migration, and function of c-kit-expressing dendritic cells in vivo (91.12)
Authors: Oriss Timothy , Krishnamoorthy Nandini , Poe Stephanie , Yarlagadda Manohar , Qi Zengbiao , Ray Prabir , Ray Anuradha
Published: January 2023

We previously reported c-kit induction on total lung DCs by in vitro treatment with Th2/Th17- (ovalbumin plus cholera toxin; OVA/CT) but not Th1-inducing (CpG) factors. Furthermore, we showed that c-kit plays a contributory role to Th2, and in particular to Th17, immune responses. Therefore, we sought to determine what, if any DC subset(s) upregulate c-kit after in vivo treatment. A basal level of c-kit expression was found on CD11c-positive, low autofluorescent DCs expressing CD11b/CX3CR1, which was upregulated following intratracheal administration of OVA/CT. Surprisingly, OVA/CpG also upregulated c-kit on CD11b/CX3CR1 DCs in vivo to an extent even greater than OVA/CT. DC expression of c-kit was highest where MHC Class II expression was also highest (i.e. following OVA/CpG treatment) suggesting that it may be linked to the activation state. However, c-kit on DCs migrating to the lung-draining lymph nodes (LNs) was markedly higher on cells from OVA/CT- versus OVA/CpG-treated animals. LN resident DCs also expressed c-kit, but it was not different between naïve and treated animals. Importantly, c-kit does appear to have functional consequences since c-kit-deficient DCs induce less IL-17 production in particular from naïve T cells, possibly due to their own decreased production of IL-6. These data suggest that c-kit expression, and possibly interaction with its ligand, stem cell factor, is important for migration to draining LNs and for skewing naïve T cell priming by DCs.
Mast Cells Expression of the ADAM-10 Protease is Inhibited BY IL-10 and TGFb1 (91.13)
Authors: Ryan John , Vance Bretton , Williams Kathryn , Morales Johanna
Published: January 2023

Asthma is an inflammatory lung disease that is caused in part by mast cell activation via IgE and antigen. B cell-mediated IgE secretion is suppressed by the low affinity IgE receptor, CD23. Recent data have demonstrated that CD23 function can be blocked by its cleavage with the protease ADAM-10. We demonstrate that mouse mast cells abundantly express surface ADAM-10 in vitro and in vivo. ADAM-10 surface expression is suppressed by the cytokines IL-10 and TGFb1, with approximately 50% inhibition after 3 days of culture. IL-10-mediated effects were Stat3-dependent and correlated with reduced ADAM-10 mRNA. These data suggest that IL-10 and TGFb1 may suppress allergic disease in part by reducing the effects of ADAM-10, allowing for CD23-mediated negative feedback. Supported by NIH grants 1R01 AI59638 and U19A1077435.
Antigen persistence and the control of local T cell memory by migrant respiratory dendritic cells following acute virus infection (92.11)
Authors: Kim Taeg , Hufford Matthew , Sun Jie , Braciale Thomas
Published: January 2023

Acute viral infections induce robust adaptive immune responses resulting in virus clearance. Recent evidence suggests that there may be depots of viral antigen which persist in draining lymph nodes following virus clearance and could therefore affect the adaptive immune response and memory formation. The nature of these residual antigen depots, the mechanism of antigen persistence and impact of the persistent antigen on memory T cells remains ill-defined. Employing a murine model of influenza virus infection of the respiratory tract, we have identified respiratory dendritic cells (RDC) as an essential cell responsible for both sampling and presenting residual viral antigen. RDC in the previously infected lung capture residual viral antigen deposited in an irradiation resistant cell type(s) and transport the viral antigen to the local lymph nodes draining the site of infection where the migrant RDC present the antigen to T cells. Furthermore, we demonstrate that there is preferential localization of memory T cells to the DLN following virus clearance as a consequence of presentation of residual viral antigen by the migrant RDC to T cells in the DLN. This enriched population of antigen-specific T cells maintained in the antigen draining LN would likely provide a more rapid and robust recall T cell response to a re-infection.
Immune Response to Seasonal Influenza Vaccination (92.18)
Authors: Ramakrishnan Amritha , Altoff Keri , Pekosz Andrew , Bream Jay
Published: January 2023

The emergence of new pandemic strains of influenza highlights the need to better understand the immune response to vaccination in order to develop novel vaccine strategies. The goal of our study was to identify and assess novel markers of immune activation after vaccination. To this end, 100 healthy adults who received either the seasonal Live Attenuated Vaccine (LAIV) or the Inactivated Vaccine (TIV) were enrolled from 2006-2008. First, we measured the serum antibody titers against vaccine strains of the virus. We found that while TIV induced a robust increase in anti-influenza serum antibody titers, LAIV induced only a modest increase. We next measured the levels of 10 cytokines in the serum of vaccine recipients. Vaccination with TIV resulted in a significant reduction in the levels of TNF-α while LAIV had no effect on any of the measured cytokines. Finally, we assessed the ability of seasonal vaccination to induce neutralizing antibody titers against the pandemic 2009 H1N1 strain. Vaccination with TIV was able to induce a significant increase in cross reactive antibodies against different seasonal H1N1 strains but not against the 2009 pandemic H1N1 strain. In all, these data suggest that 1) different influenza A vaccine formulations induce unique cytokine responses in the periphery and 2) seasonal influenza vaccination does not illicit strong cross-reactive serum antibodies with 2009 H1N1.
Failure to generate protective T-cells coupled with enhanced inflammation exacerbates lung damage in a pediatric model of influenza infection (92.21)
Authors: Verhoeven David , Farber Donna
Published: January 2023

Influenza virus causes severe morbidity/mortality in young children; however the exact mechanisms driving increased pathogenesis in children, as compared to adults, is not fully defined. We determined that pediatric mice (21 days old), were actively generating memory T-cells as would be expected in young children, while memory populations were firmly established in older “adult” mice. We infected pediatric and adult mice with influenza PR8 and found pediatric mice had elevated morbidity as measured by enhanced weight loss and lower oxygen saturation levels throughout infection thus modeling higher morbidity observed in children. Early viral loads were comparable but pediatric mice failed to clear virus by 10 days post-infection that coupled with apoptosis and poor lung recruitment of the responding T-cells while adult mice generated a strong antiviral response and cleared virus. In contrast to adult mice, IL-10 was not detected in the lungs of pediatric mice thus favoring a pro-inflammatory environment predominated by innate anti-viral responses. In addition, pediatric mice had extensive lung damage and pathology throughout infection that coupled with higher levels of pro-inflammatory innate cytokines. Reciprocal T-cell transfers revealed that both the T-cells and the inflammatory lung environment contribute to lung damage in pediatric mice. Therefore, this study highlights the key inflammatory mechanisms that drive enhanced morbidity in children infected with influenza.
Development and differentiation of memory CD8+ T cells in influenza infection (92.25)
Authors: Rutigliano John , Morris Melissa , Doherty Peter , Thomas Paul
Published: January 2023

Many questions still linger regarding the development and differentiation of memory CD8+ T cells during influenza infection. Previously, it has been shown that an inverse relationship exists between virus inoculum size and the CD8+ T cell response. To this end, we examined the development and differentiation of CD8+ T cell memory populations based on specificity and effector function in a mouse model system comparing high and low pathological infections of influenza. Our findings reveal that viral titer was not the determining factor in the outcome of disease. Instead, differences in CD8+ T cell inflammation and effector function were observed for each infection dose, and these differences correlated with disease outcome. These phenotypic and functional analyses have revealed distinct effector memory CD8+ T cell populations in the context of influenza infection.
Escaping neutralization and gaining adaptation of highly pathogenic avian influenza (HPAI) H5N1 virus in interspecies evolution. (92.5)
Authors: He Wei , Li Zheng , Liu Zhonghua , Zhang Linqi , Su Yuelong , Gao George F , Li Zi , Cui Lianxian
Published: January 2023

Limited amount of mutations in hemagglutinin (HA) of highly pathogenic avian influenza (HPAI) virus H5N1 would greatly facilitate cross-species transmission of avian influenza virus from birds to human. Neutralizing antibodies (nAbs) and receptor adaptation could drive interspecies transmission. In order to investigate the contemporaneous strain-specific and cross-strain nAb response against H5N1 pseudotype viruses and HA proteins, 10 human sera and 4 bird sera were collected to analyze their neutralization and binding activities using 4 H5N1 Has. Neutralization and binding activities of mAbs against QH and XJ H5N1 Has were observed. We found that some mutations appear in the outside of the receptor binding domain (RBD) of H5N1 hemagglutinin (HA), for example at aa 90 on QH H5N1 HA, which might induce a conformational change of the RBD to escape from nAb and change receptor preference simultaneously. These mutations were deemed as “key events” particularly during interspecies transmission to ensure the original invasion successful. They were the result of positive selection caused by antibodies. Some mutations in the RBD that only induce the change of receptor preference were deemed as “maintaining adaptation” to ensure influenza variants circulating in a new species. They were the result of adaptation caused by receptor. Our results suggest that continuing appearance of these two types of mutation made the variants persist in new species.
IL-33 administration promotes both Th2 and Th17 responses and improves resolution during influenza infection (92.7)
Authors: Wissinger Erika , Vekaria Seema , Edwards Lorna , Lyonga Daphne , Godlee Alexandra , Lloyd Clare , Liew Foo , Hussell Tracy
Published: January 2023

A number of acute and chronic immunopathological diseases are driven by excessive Th1 cytokine responses. During influenza infection, Th1 cells and CTL dominate in the lungs. Whilst important for viral clearance, these cells may also cause damaging immune pathology. We now show for the first time that a newly-described cytokine, IL-33, drives Th2 cell polarization during influenza infection, and may be used to counter excessive pathology caused by Th1 cells. We show a change in expression of both endogenous IL-33 and its receptor, ST2L, in the influenza-inflamed lung. IL-33 administration improves resolution of disease and reduces the number of TNF-α and IFN-γ-secreting CD4 and CD8 T cells in the airways of influenza-infected animals. Critically, this reduction in anti-viral T cell number does not impair viral clearance nor alter the recall response. Surprisingly, IL-33 treatment during influenza infection also promotes Th17 cell development. Our data suggest that IL-33 mediates these effects via respiratory epithelium-derived TSLP. This interaction drives a Th17-promoting cytokine cascade involving IL-23 and IL-21. Though viral-induced illness is lessened by IL-33 treatment alone, further improvements are observed when IL-33 is given in combination with IL-17A depletion. These results have important implications for pathologies associated with both Th1 and Th17 cytokine profiles and may explain how an increase of IL-33 correlates with a worsening of disease.
CD8+ T cell effector activity is localized within the pulmonary interstititum, not the airspaces, during influenza infection (92.9)
Authors: Hufford Matthew , Kim Taeg , Sun Jie , Braciale Thomas
Published: January 2023

CD8+ cytolytic T lymphocytes (CTLs) play a crucial role in the resolution of respiratory viral infections through their ability to eliminate infected cells and to release potent anti-viral cytokines. In the influenza viral model, CD8+ CTL effector activity is believed to be focused on respiratory epithelial cells, since these cells are the principal cell types supporting influenza replication. Utilizing the prototypical T cell anti-viral cytokine, IFNγ, as a measure of CD8+ CTL effector activity, we evaluated the tempo of the CD8+ CTL response to influenza infection in vivo in two compartments, the airways overlying the respiratory epithelium and the infected lung interstitium. Surprisingly, CD8+ CTL effector activity was localized not to the respiratory epithelium but within the pulmonary interstitium. We were able to establish, utilizing bone marrow chimeric mice, that infiltrating inflammatory cells of hematopoietic origin were the primary stimulus of CD8+ CTL effector activity. Additionally, we further demonstrated that lung resident CD11c+ cells, likely macrophages and/or dendritic cells, were triggering CD8+ CTL anti-viral activity. These observations suggest that inflammatory mononuclear cells are serving as the primary antigen presenting cells for effector CD8+ CTLs responding within the lungs to infection. CD8+ CTL recognition of infected respiratory epithelial cells appears to serve only a secondary role in orchestrating the pro-inflammatory T cell response.
A CD23+/CD21high B cell population selectively accumulates in the lymph nodes draining inflamed joints in the human TNF- α transgenic mouse model of rheumatoid arthritis (93.18)
Authors: Moshkani Safiehkhatoon , Li Jie , Kuzin Igor , Proulx Steven , Xing Lianping , Schwarz Edward , Bottaro Andrea
Published: January 2023

Clinical benefits from anti-TNF and B cell depletion therapy in the treatment of rheumatoid arthritis (RA) highlight the important roles of both TNF-α and B cells in the pathogenesis of RA. However, the precise role of B cells in pathogenesis of RA is not yet defined. Human TNF-α transgenic mice (hTNFtg) develop a chronic inflammatory-erosive joint disease similar to RA, and provide a useful model for studying disease pathogenesis. During progression of the disease in the knee of hTNFtg mice, the adjacent popliteal lymph node (PLN) increases in volume and cellularity and undergoes significant histological changes. These changes are accompanied by a major expansion in a polyclonal B cell subset with a unique surface phenotype (CD23+, CD21high, IgMhigh, IgD+, CD1d+), which is found specifically in the nodes draining affected joints. Interestingly, the same B cell population is also found in PLNs of K/BxN mice with an etiologically distinct, autoantigen-dependent form of arthritis. Here we will discuss the features of this new population in the context of arthritis and other inflammatory conditions.
Transgenic Expression of the RNA-sensing Molecule MDA-5 Accelerates Autoimmunity in the Lupus-prone FcgammaR2-Deficient Mouse (93.20)
Authors: Crampton Steve , Deane Jonathan , Hasty Karen , Otubusin Owokunile , Bolland Silvia
Published: January 2023

Nucleic-acid sensing molecules provide a first line of defense against microbial infections, but recent studies have shown that their inappropriate activation could promote autoimmunity. MDA-5 senses virally-derived RNA in the cytoplasm, which leads to type one interferon (IFN) production, recently shown to be associated with systemic lupus erythematosus. Here, we have generated mice with multiple copies of Ifih1, the gene that encodes MDA-5, and crossed them to the lupus-prone FcgammaRIIB-/- mouse. Mice with enhanced MDA-5 expression and FcgammaRIIB deficiency have accelerated autoimmunity with splenomegaly and anti-nuclear antibodies in their serum compared to FcgammaRIIB-deficient mice alone. They also display elevated levels of splenic plasma and germinal center B cells, indicating possible early autoreactive B cell formation. Bone marrow and splenic macrophage/monocytes from MDA5 transgenic animals also display an activated phenotype, characterized by elevated Ly6A/E, PDCA-1 and CD80 expression. B cells from MDA-5-transgenic animals also express elevated levels of type one IFN signature genes. These results suggest that increased expression of MDA-5 could exacerbate lupus, possibly through the early production of type one IFN.
Lung antigen presenting cells in human emphysema (93.21)
Authors: Shan Ming , Cheng Han-Fang , Corry David , Kheradmand Farrah
Published: January 2023

Exposure to tobacco smoke activates innate and adaptive immune responses that in long-term smokers have been linked to diseases of the lungs, cardiovascular system, joints, and other organs. The destruction of lung tissue that underlies smoking-induced emphysema has been associated with T helper 1 cells that recognize the matrix protein elastin. Factors that result in the development of such autoreactive T cells in smokers remain unknown but are crucial for further understanding the pathogenesis of systemic inflammatory diseases in smokers. Here, we show that lung myeloid dendritic cells were sufficient to induce T helper 1 and T helper 17 responses in CD4 T cells. T helper 1 and 17 cells are invariably present in lungs from patients with emphysema but not in lungs from normal individuals. Interleukin-17A, a canonical T helper 17 cytokine, enhanced secretion of CCL20, a chemoattractant for dendritic cells, and matrix metalloproteinase 12, a potent elastolytic proteinase, from lung macrophages. Thus, although diverse lung factors potentially contribute to T helper effector differentiation in vivo, lung myeloid dendritic cells direct the generation of pathogenic T cells and support a feedback mechanism that sustains both inflammatory cell recruitment and lung destruction. This mechanism may underlie disease in other elastin-rich organs and tissues.
Chronic autoimmune activation in patients with mucopolysaccharidosis III (93.22)
Authors: Fu Haiyan , Killedar Smruti , al-Dahhak Roula , Rankin Chelsea , Wu Yee-Ling , Zhou Bi , Yu Chack-Yung , DiRosario Julianne , McCarty Douglas
Published: January 2023

Mucopolysaccharidosis (MPS) III are a group of four lysosomal storage diseases with severe neurological manifestation. While the primary pathology of MPS III is the lysosomal storage of heparan sulfates, detailed mechanisms of neuropathology are unclear. Using a mouse model, we showed that a profound neuroimmune response contributes to the CNS disease progression of MPS IIIB. Immune status in MPS III patients remains unexplored. Here, we tested peripheral blood from 12 patients with MPS III, including MPS IIIA and IIIB, to assess their immune status. White blood cell differential showed higher lymphocyte ratio (48-70%) in majority tested MPS III patients than healthy control children (41-54%). PBWC from all patients exhibited significant increase in 3H-thymidine-incorporation when stimulated ex vivo with an anti-CD3 or anti-CD40 antibody, suggesting the activation of T-cells and B-cells. Complement deposition assays showed increased levels of RBC-C4d and/or reticulocyte-C4d in majority patients, indicating an ongoing activation of the classical complement pathway. In addition, antinuclear antibodies were detected in the serum of 6 patients. No association was seen between immune activation and age/gender/disease forms. This is the first study that has demonstrated a chronic autoimmune status in MPS III patients, which may also contribute to the disease progression and may have potential as therapeutic target in these patients, as demonstrated in MPS IIIB mice.
Sydenham Chorea-derived brain autoantibody expressed in transgenic (Tg) mice targets dopaminergic neurons and reveals crossreactive anti-neuronal specificities. (93.24)
Authors: Cox Carol , Cunningham Madeleine
Published: January 2023

Mechanisms of pathogenesis of brain autoantibodies are not well defined as to functional aspects and targets in disease. We utilized V genes of Sydenham chorea derived mAb to investigate crossreactive specificities and in vivo targets after expression in Tg mice. Novel human mAb 24.3.1, derived from group A streptococcal autoimmune sequela, targeted dopamine D1 and D2 receptors and reacted with group A streptococcal carbohydrate epitope N-acetyl-beta-D-glucosamine. Anti-neuronal brain specificities included lysoganglioside on neuronal cell surface and abundant intracellular brain protein tubulin. Human mAb 24.3.1 has been shown to induce signal transduction in neuronal cells with increased Ca++ calmodulin dependent protein kinase II. Expression of chimeric IgG1a antibody in Tg mouse sera conferred reactivity with D1/D2 dopamine receptors and led to deposition on dopaminergic neurons in vivo in Tg mouse brain. IgG1a transgene was detected in vivo and in vitro with anti-allotypic antibodies against IgG1a. Immunofluorescent co-localization of allotype specific Tg antibodies and tyrosine hydroxylase demonstrated chimeric IgG1a 24.3.1 deposited and bound to dopaminergic neurons in Tg mouse brain in vivo. Tg sera and IgG1a reacted with neuronal antigens lysoganglioside, tubulin and dopamine receptors D1/D2. Our data support the hypothesis that in human disease, antibodies may bind neurons and alter brain function to induce movement and behavioral disorders such as SC and PANDAS.
Role of NK cells in TLR7-induced systemic autoimmune disease (93.30)
Authors: Voynova Elisaveta , Bolland Silvia
Published: January 2023

An inappropriate activation of innate immune pathways can lead to systemic autoimmune disease, as illustrated by the phenotype of TLR7-overexpressing transgenic mice characterized by anti-RNA antibody production, glomerulonephritis, anemia, and a pro-inflammatory interferon signature in B cells and dendritic cells. Mixed bone marrow reconstitution experiments show that NK cells expand in TLR7tg because of the NK cell intrinsic sensitivity to TLR7 stimulation. NK cells in TLR7tg mice have an unusual phenotype: most NK1.1+ cells are DX5-, CD11c+ even though they have been confirmed to be bona fide NK cells by their cytotoxic responses and lack of T cell specific markers. In vitro stimulation of TLR7tg NK cells with TLR7 agonists induced production of TNFα, MCP-1, IFNγ and particularly IL-10. To assess the function of NK cells in developing the TLR7-induced autoimmune inflammatory condition, we have bred our TLR7tg mice to IL15-deficient mice IL-15 is necessary for development of NK cells and memory CD8 cells. We have observed that in the absence of IL15 some of the pro-inflammatory subsets such as CD11c+NK cells, Ly6C+monocytes, granulocytes, conventional DCs and memory T cells are reduced compared to TLR7tg. On the other hand, spontaenous germinal centers and lymphocyte activation occur at the same rate in the absence of IL15. This results suggest that the development of spontaneous autoreactive germinal centers is independent from the myeloid expansion in TLR7tg mice.
Crystal structure of an autoimmune TCR with optimal binding to its self-antigen - an alternative strategy for escaping negative selection (93.32)
Authors: Yin Yiyuan , Li Yili , Martin Roland , Mariuzza Roy
Published: January 2023

The failure to eliminate self-reactive T cells during thymic selection is a prerequisite for autoimmunity. To escape deletion, autoreactive T cell receptors (TCRs) usually form relatively unstable complexes with their self-peptide/MHC ligands. As shown previously, these TCRs adopt suboptimal binding topologies as opposed to anti-microbial TCRs. In other cases, escape can be mediated by weak binding between self-peptides and MHC. Here, we determined the crystal structure, to 2.7 Å resolution, of a human MHC class II-restricted autoimmune TCR (3C8) bound to its self-antigen, MBP 114-126/HLA-DR4. TCR 3C8, which was originally isolated from a multiple sclerosis patient, has demonstrated pathogenic potential in humanized transgenic mice. The MBP self-peptide binds HLA-DR4 with unusually low affinity. The structure showed a loose accommodation of MBP in the peptide binding groove. By contrast, 3C8 binds to MBP/HLA-DR4 at the high end of the affinity range for TCR-peptide/MHC interactions. Moreover, 3C8 engages its self-ligand via a docking mode that closely resembles the optimal binding topology of anti-foreign TCRs, but is distinct from that of other autoreactive TCRs. Thus, the 3C8-MBP/HLA-DR4 complex reveals the structural basis for an alternative strategy by which autoreactive T cells escape negative selection, yet still retain the ability to become sufficiently activated in the periphery to be pathogenic.
HLA motifs associated with autoantibody production and cross-racial similarities in systemic sclerosis using the SFVT approach (93.37)
Authors: Marthandan Nishanth , Guidry Paula , Thomson Glenys , Helmberg Wolfgang , Marsh Steven , Arnett Frank , Karp David , Scheuermann Richard
Published: January 2023

Significant associations have been found between specific HLA alleles and a variety of autoimmune diseases. Current studies treat each HLA allele as a single complete unit, which does not distinguish the parts of the molecule associated with disease or the production of particular autoantibodies. This approach also cannot uncover similarities in different predisposing alleles across races. We previously developed a novel approach for genetic association analysis in which HLA proteins are broken down into smaller sequence features (SF) with polymorphisms in these features categorized as variant types (VT). Using the SFVT approach, we analyzed DRB1, DQA1 and DQB1 typing data in a cohort of patients with Systemic Sclerosis (SSc) and demographically matched controls. We found similar predisposing and protective SFVTs in African Americans, Caucasians and Hispanics (e.g. the predisposing 67F_70D_71R peptide binding/TCR recognition motif) despite differences in the frequencies of predisposing and protective alleles that carry these SFVTs in these populations. In addition, we found that SFVTs that differ by only a few amino acids are significantly associated with the presence or absence of different autoantibodies in SSc patients (e.g. the antigen binding motif 9W_57D_60Y_67L was associated with anti-centromere, while 9E_57D_60Y_67F was associated with anti-topoisomerase). These results highlight the ability of the SFVT approach to shed light on the role of HLA in autoimmune disease.
Inhibition of type 1 diabetes by a Lactobacillus johnsonii mediated Th17 bias (93.4)
Authors: Lau Kenneth , Benitez Patrick , Ardisone Alexandria , Lorca Graciela , Li Nan , Sankar Dhyana , Neu Josef , Atkinson Mark , Larkin Joseph
Published: January 2023

Although it is known that resident gut flora contribute to immune system function and homeostasis, the role of gut flora in the progression of autoimmune disease is poorly understood. It has recently been shown that distinct bacterial populations are present within rodent models prone (DP) and resistant (DR) to Type 1 Diabetes (T1D). Oral Transfer of Lactobacillus johnsonii (N62) from DR rodent to DP rodents conferred T1D resistance to DP rodents. Diabetes resistance in N62 fed DP rodents was correlated to a TH17 bias within the mesenteric lymph nodes which was associated with high levels of IL6 and IL23. Moreover, In vitro assays show that Lactobacillus Johnsonii mediates high IL6 and IL10 levels in antigen presenting cells which can mediate TH17 differentiation in the presence of sufficient TCR stimulation. Together, these data suggest an interesting paradigm whereby autoimmunity can be circumvented by gut flora mediated, T cell differentiation.
Role of T cell mediated inflammation in lupus-like glomerulonephritis (GN) (93.40)
Authors: Bagavant Harini , Scindia Yogesh , Nandula Seshagiri , Deshmukh Umesh
Published: January 2023

Renal involvement in lupus is characterized by glomerular immune complexes, acute proliferative GN and progressive renal failure. To investigate the pathogenic role of T cells in renal lupus, an antigen-specific model of GN was established. A novel, anti-α8 integrin immunoliposomal delivery system (α8ILs) was designed for targeted delivery to the renal glomerulus. Ovalbumin loaded α8ILs (ova-α8ILs) were injected i.v. into C57BL/6 mice leading to a rapid delivery of ova in the glomerular mesangium. Injection of ova-α8ILs followed by ova-reactive transgenic OT2 cells activated in vitro, resulted in GN. On day 7 after injection, the renal cortex showed T cell, macrophage and dendritic cell infiltration. To mimic lupus GN, mice were injected with ova-α8ILs and mouse anti-ova serum forming glomerular immune complexes. This was followed by injection of naïve CSFE labeled OT2 cells. Two days after cell transfer, mice with glomerular immune complexes showed dividing OT2 cells preferentially in renal lymph nodes compared to mice given ova-α8ILs alone. Recently, macrophage infiltration into the renal interstitium has been identified as the harbinger of renal failure. Our data suggest that glomerular antigen-specific T cell infiltration may be sufficient for recruitment of macrophages into the renal cortex and the onset of progressive renal inflammation. In addition, glomerular immune complexes lead to a rapid, local activation of glomerular antigen reactive T cells.
CD4+ T cells are required for CD8+ T-cell activation but not for CD8+ T cell effector function for induction of thyrocyte hyperplasia (TEC H/P) and fibrosis (93.7)
Authors: Yu Shiguang , Sharp Gordon C. , Braley-Mullen Helen
Published: January 2023

IFN-γ-/-NOD.H-2h4 mice develop TEC H/P and fibrosis characterized by abnormal proliferation of thyrocytes and infiltration of thyroids by CD4+ and CD8+ T cells. CD8+ T cells are the primary effector cells for TEC H/P. CD4-/- and CD8-/- IFN-γ-/- NOD.H-2h4 mice were generated to determine if CD4+ T cells were required for activation of CD8+ T cells that induce TEC H/P and fibrosis. 60-70% of IFN-γ-/- mice given NaI water for 6-7 mo develop severe TEC H/P and fibrosis, compared to 11 of 53 (21%) CD4-/- mice and only 2 of 42 (5%) CD8-/- mice. TEC H/P incidence in CD4-/- mice given splenocytes from CD8-/- mice is similar to that of IFN-γ-/- mice (60%). Splenocytes from IFN-γ-/- donors with severe TEC H/P transfer severe TEC H/P to SCID recipients after culture in vitro for 72 hr, and purified CD8+ T cells from the same donors also transfer severe TEC H/P to SCID recipients. Splenocytes from some CD4-/- donors with severe TEC H/P can transfer severe TEC H/P to SCID recipients, but more often they transfer only minimal disease. These results suggest that CD4+ T cells are required for optimal activation of CD8+ T cells that induce TEC H/P, and they may also be important for optimal in vitro activation of CD8+ T cells that induce severe TEC H/P. In contrast, after CD8+ T cells are fully activated, CD4+ T cells are not required for their mobilization to thyroids or for effector function leading to TEC H/P and fibrosis.
Development of a novel anti-FimH vaccine using a mast cell activator as the adjuvant. (94.1)
Authors: Shelburne Christopher , Li Guojie , Staats Herman , Abraham Soman
Published: January 2023

Urinary tract infections (UTIs) are one of the most common bacterial infections of man. Because of their high rate of recurrence and the increase in resistance of bacteria to antibiotics, there is great interest in developing a prophylactic vaccine to limit UTIs. Unfortunately, efforts to develop such a vaccine have failed in humans, quite possibly due to the use of alum as the vaccine adjuvant which does not induce protective immune responses along the urinary tract. Here, we demonstrate that a novel anti-UTI vaccine formulation consisted of the UTI vaccine antigen FimH and a mucosal mast cell activating adjuvant compound, mastoparan-7 is able to evoke protective immune responses against UTI. This vaccine formulation induced high titer anti-FimH IgA and IgG in both the urine and serum of immunized mice that were protective against subsequent challenge of the bladder site with uropathogenic E. coli. These anti-FimH responses were comparable to those elicited by FimH vaccine formulations containing cholera toxin as the adjuvant, and superior to those elicited by formulations containing the adjuvants CpGs or alum. These studies suggest that formulation of an anti-UTI vaccine with a MC activator and the FimH antigen might result in a successful anti-UTI vaccine in humans.
β-arrestins mediate lipopolysaccharide-induced inflammatory response and endotoxemia in mice (94.10)
Authors: Parameswaran Narayanan , Gonipeta Babu , Parvataneni Sitaram , Appledorn Daniel , Patial Sonika , Gangur Venugopal , Amalfitano Andrea , Porter Katie
Published: January 2023

β-arrestins are scaffolding proteins recently implicated as negative regulators of Toll-like receptor-4 (receptor for lipopolysaccharide from gram-negative bacteria) signaling in macrophages and fibroblasts. Unexpectedly, we find that β-arrestin-1 (β-arr-1) and -2 knockout mice are protected from endotoxic shock and lethality. Consistent with this, LPS-induced inflammatory cytokine (IL-1β, IL-12p40, IL-4, IL-5 and IFNγ) levels in the plasma are markedly inhibited in both β-arr-1 and -2 knockout mice, compared to the wild types. To identify the possible mechanisms involved, we examined the effect of LPS-induced cytokine production in CD11b+ and CD11b- splenocytes. Both splenocyte populations from β-arr-2 knockout mice showed a marked decrease LPS-induced IL1-β, IL-12p40, IL-5 and IFNγ whereas these cytokines were inhibited in the β-arr-1 knockout only in the CD11b- cells, when compared to wild type splenocytes. Further experiments on the signaling pathways indicate that the role of β-arrestins is independent of MAPK and IκBα pathways in both splenocyte populations. Interestingly LPS-induced increase in histone acetyl transferase activity in the spleen is significantly inhibited in both β-arr-1 and -2 knockout mice, suggesting chromatin modification as one potential mechanism. Taken together, these results indicate that both β-arrestins have overlapping but non-redundant and cell-type-specific roles in regulating LPS-induced inflammatory cytokine production in vivo.
Innate Immune Signaling Pathways in Reactome (94.13)
Authors: Haw Robin , Caudy Michael , Croft David , Garapati Phani , Gillespie Marc , Jassal Bijay , Jupe Steven , Kanapin Alexander , Mahajan Shahana , Matthews Lisa , May Bruce , O'Kelly Gavin , Schmidt Esther , Shamovsky Veronica , Wu Guanming , Birney Ewan , Hermjakob Henning , D'Eustachio Peter , Stein Lincoln
Published: January 2023

Toll-like receptors (TLR) play a key role in the innate immune system, providing vertebrates with a critical first line of defense against invading microbial pathogens. With the increasing body of molecular data relating to TLR function, organizing this information is useful to biologists and immunologists. We have used Reactome (www.reactome.org), a manually curated pathway database, to organize TLR data so that it can be viewed like an electronic textbook. TLR signaling cascades were authored by experts, maintained by the Reactome editorial staff and cross-referenced to publicly available bioinformatics resources. The Reactome data model generalizes the concept of a biochemical reaction to encompass any transformation of an input set of physical entities into an output set, and thus allows us to integrate TLR cascades with other innate immune processes, adaptive immunity, metabolic pathways, and other signaling processes. Since TLR-signaling molecules and pathways and the signaling pathways they initiate are highly conserved, Reactome provides pathway inference for 22 species based upon improved orthology prediction methods. A new entity-level pathway viewer and pathway analysis tools facilitate searching and visualizing pathway data and the analysis of user-supplied high-throughput data sets. All data content and software can be freely used and redistributed under open source terms.