pinecone/core-2020-05-10-deduplication huggingface dataset:
Pulmonary innate lymphoid cells are major producers of IL-5 and IL-13 in murine models of allergic asthma

Allergic asthma is characterized by chronic airway inflammation and hyperreactivity and is thought to be mediated by an adaptive T helper-2 (Th2) cell-type immune resp-onse. Here, we demonstrate that type 2 pulmonary innate lymphoid cells (ILC2s) significantly contribute to production of the key cytokines IL-5 and IL-13 in experimental asthma. In naive mice, lineage-marker negative ILC2s expressing IL-7Rα, CD25, Sca-1, and T1/ST2(IL-33R) were present in lungs and mediastinal lymph nodes (MedLNs), but not in broncho-alveolar lavage (BAL) fluid. Upon intranasal administration of IL-25 or IL-33, an asthma phenotype was induced, whereby ILC2s accumulated in lungs, MedLNs, and BAL fluid. After IL-25 and IL-33 administration, ILC2s constituted ~50 and ~80% of IL-5 +/IL-13 + cells in lung and BAL, respectively. Also in house dust mite-induced or ovalbumin-induced allergic asthma, the ILC2 population in lung and BAL fluid increased significantly in size and ILC2s were a major source of IL-5 or IL-13. Particularly in OVA-induced asthma, the contribution of ILC2s to the total population of intracellular IL-5 + and IL-13 + cells in the lung was in the same range as found for Th2 cells. We conclude that both ILC2s and Th2 cells produce large amounts of IL-5 and IL-13 that contribute to allergic airway inflammation
Impact of Mycobacterium tuberculosis and HIV-1 on innate immune mechanisms

Human immunodeficiency virus type 1 (HIV-1), a causative agent of 
acquired immunodeficiency syndrome (AIDS), and Mycobacterium tuberculosis (Mtb), 
a causative agent of tuberculosis (TB), are among the leading causes of death from 
infectious disease worldwide. Interplay between HIV-1 and Mtb leads to the 
detrimental dysregulation of immune system mechanisms, which provides the 
conditions facilitating progression of the disease in co-infected individuals. 



In order to investigate the impact of Mtb and HIV-1 on innate immune 
responses we set up in vitro infection models comprising human monocyte-derived
macrophages (Mφs) and dendritic cells (DCs). Firstly, we examined the influence of 
mycobacterial cell wall-derived glycolipids on the function of DCs. We found that 
two cell wall components, ManLAM and PIM, modulate DC function in an opposite 
manner, where ManLAM stimulates the production of pro-inflammatory cytokines, 
while PIM inhibits cytokine production triggered by activated DCs. Next, we 
analyzed several clinical Mtb isolates causing a large TB outbreak in Sweden. We 
found that the clinical isolates are characterized  by the ability to trigger increased 
production of TNF from  in vitro infected Mφs, above that triggered by the Mtb 
reference strain. Knowing that different mycobacterial glycolipids may differently 
impact DC and having several Mtb clinical isolates  characterized, we investigated 
the effects of ongoing Mtb infection on the function of bystander DCs. Here we 
demonstrated that mycobacteria-infected Mφs create  a pro-inflammatory milieu in 
which DCs undergo partial maturation, produce pro-inflammatory cytokines and 
additionally increase their ability to mediate HIV-1 trans-infection of T cells. Finally, 
we investigated mechanisms behind the altered cytokine response to Mtb during 
concurrent HIV-1 infection. We observed that the levels of cytokines released from 
Mtb-infected Mφs are lower after HIV-1 pre-exposure than those observed from 
singly Mtb-infected Mφs. Next, we measured levels of miR-146a, a microRNA 
known to inhibit signaling cascades leading to production of pro-inflammatory 
cytokines. We found that miR-146a was up-regulated upon Mtb infection and also 
after HIV-1 exposure, suggesting that HIV-triggered miR-146a expression may be 
responsible for cross-tolerance of Mφs to following Mtb infection. Furthermore, we 
showed that exposure to the HIV-1 envelope glycoprotein gp120 is sufficient to upregulate miR-146a, which in turn is paralleled by down-modulated responsiveness 
of Mφs to a secondary stimulus, i.e. the Mtb glycolipid ManLAM.



In conclusion, this thesis highlights that several innate immune mechanisms 
are modulated by either HIV-1 or Mtb, which may hamper adequate immune 
responses against the two pathogens. These studies also suggest that the effects may 
be triggered in a bystander manner, where impacted cells are not infected and may 
be even localized distantly from the site of infection
Improved adjuvanting of seasonal influenza vaccines: Pre-clinical studies of MVA-NP+M1 co-administration with inactivated influenza vaccine.

Licensed seasonal influenza vaccines induce antibody responses against influenza hemagglutinin that are limited in their ability to protect against different strains of influenza. Cytotoxic T lymphocytes (CTLs) recognizing the conserved internal nucleoprotein (NP) and matrix protein (M1) are capable of mediating a cross-subtype immune response against influenza. Modified vaccinia virus Ankara encoding NP and M1 (MVA-NP+M1) is designed to boost pre-existing T-cell responses in adults in order to elicit a cross-protective immune response. We examined the co-administration of hemagglutinin (HA) protein formulations and candidate MVA-NP+M1 influenza vaccines in murine, avian, and swine models. Antibody responses post-immunization were measured by ELISA and pseudotype neutralization assays. Here we demonstrate that MVA-NP+M1 can act as an adjuvant enhancing antibody (Ab) responses to HA while simultaneously inducing potent T-cell responses to conserved internal antigens. We show that this regimen leads to the induction of cytophilic Ab isotypes that are capable of inhibiting hemagglutination and in the context of H5 exhibit cross-clade neutralization. The simultaneous induction of T cells and antibody responses has the potential to improve seasonal vaccine performance and could be employed in pandemic situations
Naturally occurring mutation affecting the MyD88-binding site of TNFRSF13B impairs triggering of class switch recombination

Mutations in the transmembrane activator and calcium-modulating cyclophilin ligand interactor (TACI) were previously found to be associated with hypogammaglobulinemia in humans. It has been shown that proliferation inducing ligand (APRIL) elicits class switch recombination (CSR) by inducing recruitment ofMyD88 to a TACI highly conserved cytoplasmic domain (THC). We have identified a patient with hypogammaglobulinemia carrying a missense mutation (S231R) predicted to affect the THC. Aiming to evaluate the relevance of this novel mutation of TACI in CSR induction, we tested the ability of TACI, TLR9, or/and CD40 ligands to trigger CSR in naive B cells and B-cell lines carrying S231R. IgG secretion was impaired when triggered by TACI or/and TLR9 ligands on S231R-naive B cells. Likewise, these stimuli induced less expression of activation-induced cytidine deaminase, I(γ)1-C(μ), and I(γ)1-C(μ), while induction by optimal CD40 stimulation was indistinguishable from controls. These cells also showed an impaired cooperation between TACI and TLR9 pathways, as well as a lack of APRIL-mediated enhancement of CD40 activation in suboptimal conditions. Finally, after APRIL ligation, S231R-mutated TACI failed to colocalize withMyD88. Collectively, these results highlight the requirement of an intact MyD88-binding site in TACI to trigger CSR.Fil: Almejún, María Belén. Gobierno de la Ciudad de Buenos Aires. Hospital de Pediatría "Juan P. Garrahan". Laboratorio de Investigación; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas; ArgentinaFil: Cols, Montserrat. Mount Sinai School of Medicine. Department of Medicine; Estados UnidosFil: Zelazko, Marta. Gobierno de la Ciudad de Buenos Aires. Hospital de Pediatría "Juan P. Garrahan". Laboratorio de Investigación; ArgentinaFil: Oleastro, Matías. Gobierno de la Ciudad de Buenos Aires. Hospital de Pediatría "Juan P. Garrahan". Laboratorio de Investigación; ArgentinaFil: Cerutti, Andrea. Mount Sinai School of Medicine. Department of Medicine; Estados UnidosFil: Oppezzo, Pablo. Instituto Pasteur. Unidad de Proteínas Recombinantes; UruguayFil: Cunningham Rundles, Charlotte. Mount Sinai School of Medicine. Department of Medicine; Estados UnidosFil: Danielian, Silvia. Gobierno de la Ciudad de Buenos Aires. Hospital de Pediatría "Juan P. Garrahan". Laboratorio de Investigación; Argentin
The site of allergen expression in hematopoietic cells determines the degree and quality of tolerance induced through molecular chimerism

The transplantation of allergens (e.g. Phl p 5 or Bet v 1) expressed on BM cells as membrane-anchored full-length proteins leads to permanent tolerance at the T-cell, B-cell, and effector-cell levels. Since the exposure of complete allergens bears the risk of inducing anaphylaxis, we investigated here whether expression of Phl p 5 in the cytoplasm (rather than on the cell surface) is sufficient for tolerance induction. Transplantation of BALB/c BM retrovirally transduced to express Phl p 5 in the cytoplasm led to stable and durable molecular chimerism in syngeneic recipients (∼20% chimerism at 6 months). Chimeras showed allergen-specific T-cell hyporesponsiveness. Further, Phl p 5-specific TH1-dependent humoral responses were tolerized in several chimeras. Surprisingly, Phl p 5-specific IgE and IgG1 levels were significantly reduced but still detectable in sera of chimeric mice, indicating incomplete B-cell tolerance. No Phl p 5-specific sIgM developed in cytoplasmic chimeras, which is in marked contrast to mice transplanted with BM expressing membrane-anchored Phl p 5. Thus, the expression site of the allergen substantially influences the degree and quality of tolerance achieved with molecular chimerism in IgE-mediated allergy
TCR-engineered T cells: A model of inducible TCR expression to dissect the interrelationship between two TCRs

TCR gene modified T cells for adoptive therapy simultaneously express the Tg TCR and the endogenous TCR, which might lead to mispaired TCRs with harmful unknown specificity and to a reduced function of TCR-Tg T cells. We generated dual TCR T cells in two settings in which either TCR was constitutively expressed by a retroviral promoter while the second TCR expression was regulable by a Tet-on system. Constitutively expressed TCR molecules were reduced on the cell surface depending on the induced TCR expression leading to strongly hampered function. Besides that, using fluorescence resonance energy transfer we detected mispaired TCR dimers and different pairing behaviors of individual TCR chains with a mutual influence on TCR chain expression. The loss of function and mispairing could not be avoided by changing the TCR expression level or by introduction of an additional cysteine bridge. However, in polyclonal T cells, optimized TCR formats (cysteineization, codon optimization) enhanced correct pairing and function. We conclude from our data that (i) the level of mispairing depends on the individual TCRs and is not reduced by increasing the level of one TCR, and (ii) modifications (cysteineization, codon optimization) improve correct pairing but do not completely exclude mispairing (cysteineization)
Differential post-transcriptional regulation of IL-10 by TLR2 and TLR4-activated macrophages

The activation of TLRs by microbial molecules triggers intracellular-signaling cascades and the expression of cytokines such as IL-10. Il10 expression is tightly controlled to ensure effective immune responses, while preventing pathology. Maximal TLR-induction of Il10 transcription in macrophages requires signaling through the MAPKs, ERK, and p38. Signals via p38 downstream of TLR4 activation also regulate IL-10 at the post-transcriptional level, but whether this mechanism operates downstream of other TLRs is not clear. We compared the regulation of IL-10 production in TLR2 and TLR4-stimulated BM-derived macrophages and found different stability profiles for the Il10 mRNA. TLR2 signals promoted a rapid induction and degradation of Il10 mRNA, whereas TLR4 signals protected Il10 mRNA from rapid degradation, due to the activation of Toll/IL-1 receptor domain-containing adaptor inducing IFN-ß (TRIF) and enhanced p38 signaling. This differential post-transcriptional mechanism contributes to a stronger induction of IL-10 secretion via TLR4. Our study provides a molecular mechanism for the differential IL-10 production by TLR2- or TLR4-stimulated BMMs, showing that p38-induced stability is not common to all TLR-signaling pathways. This mechanism is also observed upon bacterial activation of TLR2 or TLR4 in BMMs, contributing to IL-10 modulation in these cells in an infection setting.Fundação para a Ciência e a Tecnologia (FCT
MyD88 signalling in myeloid cells is sufficient to prevent chronic mycobacterial infection

Tuberculosis is a chronic infectious disease caused by Mycobacterium tuberculosis that is responsible for almost 1.5 million deaths per year. Sensing of mycobacteria by the host's immune system relies on different families of receptors present on innate immune cells. Amongst them, several members of the TLR family are involved in the activation of immune cells by mycobacteria, yet the in vivo contribution of individual TLRs to the protective immune response remains controversial. On the contrary, MyD88, the adaptor molecule for most TLRs, plays a non-redundant role in the protection against tuberculosis and mice with a complete germline deletion of MyD88 succumb very early to infection. MyD88 is expressed in both immune and non-immune cells, but it is not clear whether control of mycobacteria requires ubiquitous or cell-type specific MyD88 expression. Therefore, using novel conditional switch-on mouse models, we aimed to investigate the importance of MyD88 signalling in DCs and macrophages for the induction of protective effector mechanisms against mycobacterial infection. We conclude that specific reactivation of MyD88 signalling in CD11c- or lysozyme M-expressing myeloid cells during Mycobacterium bovis Bacille Calmette-Guerin infection is sufficient to restore systemic and local inflammatory cytokine production and to control pathogen burden.Fil: Berod, Luciana. Helmholtz Centre for Infection Research; Alemania. Medical School Hanover; AlemaniaFil: Stüve, Philipp. Medical School Hanover; Alemania. Helmholtz Centre for Infection Research; AlemaniaFil: Swallow, Maxine. Medical School Hanover; Alemania. Helmholtz Centre for Infection Research; AlemaniaFil: Arnold Schrauf, Catharina. Medical School Hanover; Alemania. Helmholtz Centre for Infection Research; AlemaniaFil: Kruse, Friederike. Medical School Hanover; Alemania. Helmholtz Centre for Infection Research; AlemaniaFil: Gentilini, Maria Virginia. Consejo Nacional de Investigaciones Científicas y Técnicas; Argentina. Helmholtz Centre for Infection Research; Alemania. Medical School Hanover; AlemaniaFil: Freitag, Jenny. Medical School Hanover; Alemania. Helmholtz Centre for Infection Research; AlemaniaFil: Holzmann, Bernhard. Universitat Technical Zu Munich; Alemania. Helmholtz Centre for Infection Research; AlemaniaFil: Sparwasser, Tim. Medical School Hanover; Alemania. Helmholtz Centre for Infection Research; Alemani
Exacerbated experimental arthritis in Wiskott–Aldrich syndrome protein deficiency: Modulatory role of regulatory B cells

Patients deficient in the cytoskeletal regulator Wiskott–Aldrich syndrome protein (WASp) are predisposed to varied autoimmunity, suggesting it has an important controlling role in participating cells. IL-10-producing regulatory B (Breg) cells are emerging as important mediators of immunosuppressive activity. In experimental, antigen-induced arthritis WASp-deficient (WASp knockout [WAS KO]) mice developed exacerbated disease associated with decreased Breg cells and regulatory T (Treg) cells, but increased Th17 cells in knee-draining LNs. Arthritic WAS KO mice showed increased serum levels of B-cell-activating factor, while their B cells were unresponsive in terms of B-cell-activating factor induced survival and IL-10 production. Adoptive transfer of WT Breg cells ameliorated arthritis in WAS KO recipients and restored a normal balance of Treg and Th17 cells. Mice with B-cell-restricted WASp deficiency, however, did not develop exacerbated arthritis, despite exhibiting reduced Breg- and Treg-cell numbers during active disease, and Th17 cells were not increased over equivalent WT levels. These findings support a contributory role for defective Breg cells in the development of WAS-related autoimmunity, but demonstrate that functional competence in other regulatory populations can be compensatory. A properly regulated cytoskeleton is therefore important for normal Breg-cell activity and complementation of defects in this lineage is likely to have important therapeutic benefits
IL-33 attenuates the development of experimental autoimmune uveitis

Interleukin-33 (IL-33) is associated with several important immune-mediated disorders. However, its role in uveitis, an important eye inflammatory disease, is unknown. Here, we investigated the function of IL-33 in the development of experimental autoimmune uveitis (EAU). IL-33 and IL-33 receptor (ST2) were expressed in murine retinal pigment epithelial (RPE) cells in culture, and IL-33 increased the expression of Il33 and Mcp1 mRNA in RPE cells. In situ, IL-33 was highly expressed in the inner nuclear cells of the retina of naïve mice, and its expression was elevated in EAU mice. ST2-deficient mice developed exacerbated EAU compared with WT mice, and administration of IL-33 to WT mice significantly reduced EAU severity. The attenuated EAU in IL-33-treated mice was accompanied by decreased frequency of IFN-γ+ and IL-17(+) CD4+ T cells and reduced IFN-γ and IL-17 production but with increased frequency of IL-5(+) and IL-4(+) CD4 T cells and IL-5 production in the draining lymph node and spleen. Macrophages from the IL-33-treated mice show a significantly higher polarization toward an alternatively activated macrophage phenotype. Our results therefore demonstrate that the endogenous IL-33/ST2 pathway plays an important role in EAU, and suggest that IL-33 represents a potential option for treatment of uveitis
Rapid CD4⁺ T-cell responses to bacterial flagellin require dendritic cell expression of Syk and CARD9

Toll‐like receptors (TLRs) can recognize microbial patterns and utilize adaptor molecules, such as‐MyD88 or (TRIF TIR‐domain‐containing adapter‐inducing interferon‐β), to initiate downstream signaling that ultimately affects the initiation of adaptive immunity. In addition to this inflammatory role, TLR5 expression on dendritic cells can favor antigen presentation of flagellin peptides and thus increase the sensitivity of flagellin‐specific T‐cell responses in vitro and in vivo. Here, we examined the role of alternative signaling pathways that might regulate flagellin antigen presentation in addition to MyD88. These studies suggest a requirement for spleen tyrosine kinase, a noncanonical TLR‐signaling adaptor molecule, and its downstream molecule CARD9 in regulating the sensitivity of flagellin‐specific CD4⁺ T‐cell responses in vitro and in vivo. Thus, a previously unappreciated signaling pathway plays an important role in regulating the dominance of flagellin‐specific T‐cell responses
Innate immunity in atherosclerosis : the role of pattern recognition receptors

The pathogenesis of atherosclerosis is greatly influenced by the activities of both innate and 
adaptive immunity. Danger signals such as cholesterol crystals, oxidized LDL, and modified 
phospholipids may trigger sterile inflammation in atherosclerosis. Systemic infection or 
transient release of pathogen associated molecules in the circulation might also activate 
immune system and affect atherosclerosis. Activation of the innate immunity relies on a set of pattern recognition receptors (PRRs). Thus, PRRs are fundamental for activating the innate immunity in atherosclerosis.



This thesis focuses on the role of three different PRRs in atherosclerosis, including NOD1, 
NOD2 and TLR9. We hypothesized that these PRRs regulate immune responses in the 
pathogenesis of atherosclerosis.



We found that NOD2 is expressed in endothelial cells and macrophages in atherosclerotic 
plaques, and lesional NOD2 signal leads to activation of PGE2 pathway via NF-kB and 
MAPK p38. NOD2 activation in vivo promotes the development of vulnerable atherosclerotic 
plaques, characterized by enlarged necrotic core in the atherosclerotic plaques and enhanced 
vascular inflammation. Furthermore, NOD2 induces lipid retention in macrophages may 
contribute to the necrotic core formation.



Although belonging to the same family, NOD1 signal promotes another lesional phenotype 
characterized by occlusive atherosclerosis with elastin degradation and vascular smooth 
muscle cell (VSMC) activation. In vitro stimulation of SMCs with NOD1 ligand induces 
chemokine and MMP production as well as enhances migration ability. Our data point to a 
possible mechanism via NOD1 in the development of occlusive atherosclerotic lesions.



Unlike NOD1 and NOD2, TLR9 stimulation decreases atherosclerosis and necrotic core 
albeit activates local and systemic inflammation. Two important anti-inflammatory mediators 
IL-10 and IDO are induced by TLR9 activation and are potential contributors to the 
mechanisms that TLR9 restrains atherosclerosis.



In summary, we identified three innate immune pathways linked to the distinct features of 
atherosclerosis. NOD2 leads to formation of vulnerable plaques with big necrotic cores. NOD1 promotes severe occlusive atherosclerosis. TLR9 signal restrains the development of atherosclerosis
Signal regulatory protein alpha (SIRPα) regulates the homeostasis of CD103⁺CD11b⁺ DCs in the intestinal lamina propria

Signal regulatory protein alpha (SIRP alpha/CD172a) is a conserved transmembrane protein thought to play an inhibitory role in immune function by binding the ubiquitous ligand CD47. SIRP alpha expression has been used to identify dendritic cell subsets across species and here we examined its expression and function on intestinal DCs in mice. Normal mucosa contains four subsets of DCs based on their expression of CD103 and CD11b and three of these express SIRP alpha. However, loss of SIRP alpha signaling in mice leads to a selective reduction in the CD103(+)CD11b(+) subset of DCs in the small intestine, colon, and amongmigratory DCs in the mesenteric lymph node. In parallel, these mice have reduced numbers of T(H)17 cells in steady-state intestinal mucosa, and a defective T(H)17 response to Citrobacter infection. Identical results were obtained in CD47KO mice. DC precursors from SIRP alpha mutant mice had an enhanced ability to generate CD103(+)CD11b(+) DCs in vivo, but CD103(+)CD11b(+) DCs from mutant mice were more prone to die by apoptosis. These data show a previously unappreciated and crucial role for SIRP alpha in the homeostasis of CD103(+)CD11b(+) DCs in the intestine, as well as providing further evidence that this subset of DCs is critical for the development of mucosal T(H)17 responses