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Levy, O.

Publications and source records attributed to Levy, O..

At least 37 records · Page 2Linked to original sources

Adjuvant Discovery via a High Throughput Screen using Human Primary Mononuclear Cells

We describe a methodology utilizing high-throughput and high-content screening for novel adjuvant candidates that was used to screen a library of [~]2,500 small molecules via a 384-well quantitative combined cytokine and flow cytometry immunoassay in primary human peripheral blood mononuclear cells (PBMCs) from 4 healthy adult study participants. Hits were identified based on their induction of soluble cytokine (TNF, IFN{gamma} and IL-10) secretion and PBMC maturation (CD 80/86, Ox40, and HLA-DR) in at least two of the four donors screened. From an initial set of 197 compounds identified using these biomarkers--an 8.6% hit rate--we downselected to five scaffolds that demonstrated robust efficacy and potency in vitro and evaluated the top hit, vinblastine sulfate, for adjuvanticity in vivo. Vinblastine sulfate significantly enhanced murine humoral responses to recombinant SARS-CoV-2 spike protein, including a four-fold enhancement of IgG titer production when compared to treatment with the spike antigen alone. Overall, we outline a methodology for discovering immunomodulators with adjuvant potential via high-throughput screening of PBMCs in vitro that yielded a lead compound with in vivo adjuvanticity. MotivationVaccines are a key biomedical intervention to prevent the spread of infectious diseases, but their efficacy can be limited by insufficient immunogenicity and nonuniform reactogenic profiles. Adjuvants are molecules that potentiate vaccine responses by inducing innate immune activation. However, there are a limited number of adjuvants in approved vaccines, and current approaches for preclinical adjuvant discovery and development are inefficient. To enhance adjuvant identification, we developed a protocol based on in vitro screening of human primary leukocytes.

immunology↗

Shaping neonatal immunization by tuning delivery of synergistic adjuvants via nanocarriers

Adjuvanted nanocarrier-based vaccines hold substantial potential for applications in novel early-life immunization strategies. Here, via mouse and human age-specific in vitro modelling, we identified the combination of a small molecule STING agonist (2'3'-cyclic GMP-AMP, cGAMP) and a TLR7/8 agonist (CL075) to drive synergistic activation of neonatal dendritic cells and precision CD4 Th cell expansion via the IL-12/IFN{gamma} axis. We further demonstrate that vaccination of neonatal mice with quadrivalent influenza recombinant hemagglutinin (rHA) and an admixture of two polymersome (PS) nanocarriers separately encapsulating-cGAMP (cGAMP-PS) and CL075 (CL075-PS) drove robust T helper (Th)1 bias, high frequency of T follicular helper (TFH) cells and germinal center B (GC B) cells along with IgG2c-skewed humoral response in vivo. Dual loaded cGAMP/CL075-PSs did not outperform admixed cGAMP-PSs and CL075-PSs in vivo. These data validate an optimally designed adjuvantation system, via age-selected small molecule synergy and a multi-component nanocarrier formulation, as an effective approach to induce type 1 immune responses in early life.

immunology↗

Transcriptional atlas of the human immune response to 13 vaccines reveals a common predictor of vaccine-induced antibody responses

Systems biology approaches have been used to define molecular signatures and mechanisms of immunity to vaccination. However, most such studies have been done with single vaccines, and comparative analysis of the response to different vaccines is lacking. We integrated temporal transcriptional data of over 3,000 samples, obtained from 820 healthy adults across 28 studies of 13 different vaccines and analyzed vaccination-induced signatures associated with the antibody response. Most vaccines induced similar kinetics of shared transcriptional signatures, including signatures of innate immunity occurring 1-3 days post-vaccination, as well as the canonical plasmablast and cell cycle signatures appearing 7 days post-vaccination. However, the yellow fever vaccine YF-17D uniquely induced an early transient signature of T and B cell activation at Day 1, followed by delayed antiviral/interferon and plasmablast signatures that peaked at Days 7 and 14-21, respectively. Thus, despite the shared transcriptional response to most vaccines, at any given time point there was no evidence for a "universal signature" that could be used to predict the antibody response to all vaccines. However, accounting for the asynchronous nature of responses led to the identification of a time-adjusted signature that improved prediction antibody of responses across vaccines. These results provide a transcriptional atlas of the human immune response to vaccination and define a common, time-adjusted signature of antibody responses to vaccination.

immunology↗

Determinants of precocious B-cell aging in European adolescences living with perinatally acquired HIV-1 after over 10 years of suppressive therapy

HIV infection results in a state of chronic immune activation leading to premature immune aging, B-cells dysfunction, that persists despite prolonged virological suppression. In this scenario, adolescence living with perinatally acquired HIV (PHIV), deserve a peculiar attention since potentially exposed for their entire life to chronic immune activation. Here we identified determinants of precocious aging B cells in 40 PHIV undergoing suppressive antiretroviral therapy (ART) for median 13.5 years. All individuals started ART by 2nd year of life and achieved virus suppression within the 1st year of ART, with majority of patient maintaining suppression until analysis and 5/40 experiencing viral Spike (transient elevation of HIV-1 VL, 50-999 copies/ml). We employed a multiomics approach including deep immunological B and T cell phenotype in PBMC, with aging B cells defined by the expression of T-bet and CD11c; plasma proteomics analysis by mass spectrometry and serum level of anti-measles antibodies as correlates of humoral response. We found that individuals with expansion of aging B cell, defined by the expression of T-bet+CD11c+, were those starting treatment later, presenting detectable levels of cell-associated HIV-1 RNA, history of Spikes, and a higher frequency of exhausted T-cells, including those expressing PD-1, LAG3, TIGIT. Accordingly, the proteomic analysis revealed that subjects with expansion of aging B cells and exhausted T cells had enrichment of proteins involved in immune inflammation and complement activation pathways, such as CLU and APCS which are also involved in tumor progression. Signs of precocious aging were associated with a reduced capacity to maintain virological memory against measles vaccination. To our knowledge, this is the first study focusing on precocious B-cell aging and dysfunctionality in PHIV with long-term virological suppression. Our experimental strategy enabled identification of clinical, viral, cellular and plasma soluble markers associated with B-cells aging. Our results pave the way to further define risk of disease progression or lymphoproliferative disorders in PHIV. Author summaryDespite a successful antiretroviral therapy (ART), adolescence living with perinatally acquired HIV (PHIV) experience B-cells dysfunction, including loss of vaccine-induced immunological memory and higher risk of developing B-cells associated tumors. It is thus paramount to define novel and precise correlates of precious aging B cell for the definition of novel therapeutic strategies. Here, we studied 40 PHIV who started treatment by 2nd year of life and maintain virological suppression for 13.5 years, with 5/40 patients experiencing transient elevation of the HIV-1 load in the plasma (Spike). We applied a multi-omics approach including immunological B and T cell phenotype, plasma proteomics analysis and serum level of anti-measles antibodies as functional correlates of vaccine-induced immunity. We found that levels of aging B cells were positively associated with age at ART start, cell associated HIV-1 RNA (caHIV-1 RNA) and the presence of Spikes. Individuals with increased proportions of aging B cells had concomitant expansion of exhausted T cells and were unable to maintain vaccine-induced immunity over time. B-cell aging, and T-cell exhaustion were also associated with proteins involved in immune inflammation. The factors found here to be associated with aging B-cell could inform further therapeutic studies.

immunology↗

The Immune Signatures Data Resource: A compendium of systems vaccinology datasets

Vaccines are among the most cost-effective public health interventions for preventing infection-induced morbidity and mortality, yet much remains to be learned regarding the mechanisms by which vaccines protect. Systems immunology combines traditional immunology with modern omic profiling techniques and computational modeling to promote rapid and transformative advances in vaccinology and vaccine discovery. The NIH/NIAID Human Immunology Project Consortium (HIPC) has leveraged systems immunology approaches to identify molecular signatures associated with the immunogenicity of many vaccines, including those targeting seasonal influenza, yellow fever, and hepatitis B. These data are made available to the broader scientific community through the ImmuneSpace data portal and analysis engine leveraging the NIH/NIAID ImmPort repository1,2. However, a barrier to progress in this area is that comparative analyses have been limited by the distributed nature of some data, potential batch effects across studies, and the absence of multiple relevant studies from non-HIPC groups in ImmPort. To support comparative analyses across different vaccines, we have created the Immune Signatures Data Resource, a compendium of standardized systems vaccinology datasets. This data resource is available through ImmuneSpace, along with code to reproduce the processing and batch normalization starting from the underlying study data in ImmPort and the Gene Expression Omnibus (GEO). The current release comprises 1405 participants from 53 cohorts profiling the response to 24 different vaccines and includes transcriptional profiles and antibody response measurements. This novel systems vaccinology data release represents a valuable resource for comparative and meta-analyses that will accelerate our understanding of mechanisms underlying vaccine responses. [Table 1]

systems biology↗

An innate immune activation state prior to vaccination predicts responsiveness to multiple vaccines

Many factors determine whether an individual responding to vaccination will generate an immune response that can lead to protection. Several studies have shown that the pre-vaccination immune state is associated with the antibody response to vaccines. However, the generalizability and mechanisms that underlie this association remain poorly defined. Here, we sought to identify a common pre-vaccination signature and mechanisms that could predict the immune response across a wide variety of vaccines. We leveraged the "Immune Signatures Data Resource" created by the NIH Human Immunology Project Consortium (HIPC) to integrate data from 28 studies involving 13 different vaccines and associate the blood transcriptional status of 820 healthy young adults with their responses. An unsupervised analysis of blood transcriptional profiles across studies revealed three distinct pre-vaccination states, characterized by the differential expression of genes associated with a pro-inflammatory response, cell proliferation, and metabolism alterations downstream of NF{kappa}B and IRF7. Innate and adaptive immune cell subset-specific genes were also associated with the three pre-vaccination states. Importantly, individuals whose pre-vaccination state was enriched in pro-inflammatory response genes known to be downstream of NF{kappa}B tended to have higher serum antibody responses one month after vaccination. A supervised analysis of the same data resulted in a single classifier, also enriched for NF{kappa}B regulated genes, that predicted the antibody response across most of the vaccines. Projection into single-cell RNA-sequencing data suggested that this pre-vaccination state was attributable to the signature of activation of non-classical monocytes and myeloid dendritic cells. Transcriptional signatures of acute responses to bacterial and not viral infections were enriched in the high pro-inflammatory pre-vaccination state and also included NF{kappa}B regulated genes. The pro-inflammatory pre-vaccination state was highly reminiscent of the innate activation state triggered by TLR ligands or adjuvants. These results demonstrate that wide variations in the transcriptional state of the immune system in humans can be a key determinant of responsiveness to vaccination. They also define a transcriptional signature NF{kappa}B activation at baseline, that is associated with a greater magnitude of antibody response to multiple vaccines, and suggest that modulation of the innate immune system by next-generation adjuvants targeting NF{kappa}B before vaccine administration may improve vaccine responsiveness.

systems biology↗

An adjuvanted SARS-CoV-2 RBD nanoparticle elicits neutralizing antibodies and fully protective immunity in aged mice

Development of affordable and effective vaccines that can also protect vulnerable populations such as the elderly from COVID-19-related morbidity and mortality is a public health priority. Here we took a systematic and iterative approach by testing several SARS-CoV-2 protein antigens and adjuvants to identify a combination that elicits neutralizing antibodies and protection in young and aged mice. In particular, SARS-CoV-2 receptorbinding domain (RBD) displayed as a protein nanoparticle (RBD-NP) was a highly effective antigen, and when formulated with an oil-in-water emulsion containing Carbohydrate fatty acid MonoSulphate derivative (CMS) induced the highest levels of cross-neutralizing antibodies compared to other oil-in-water emulsions or AS01B. Mechanistically, CMS induced antigen retention in the draining lymph node (dLN) and expression of cytokines, chemokines and type I interferon-stimulated genes at both injection site and dLN. Overall, CMS:RBD-NP is effective across multiple age groups and is an exemplar of a SARS-CoV-2 subunit vaccine tailored to the elderly.

immunology↗

Alum:CpG adjuvant enables SARS-CoV-2 RBD-induced protection in aged mice and synergistic activation of human elder type 1 immunity

Global deployment of vaccines that can provide protection across several age groups is still urgently needed to end the COVID-19 pandemic especially for low- and middle-income countries. While vaccines against SARS-CoV-2 based on mRNA and adenoviral-vector technologies have been rapidly developed, additional practical and scalable SARS-CoV-2 vaccines are needed to meet global demand. In this context, protein subunit vaccines formulated with appropriate adjuvants represent a promising approach to address this urgent need. Receptor-binding domain (RBD) is a key target of neutralizing antibodies (Abs) but is poorly immunogenic. We therefore compared pattern recognition receptor (PRR) agonists, including those activating STING, TLR3, TLR4 and TLR9, alone or formulated with aluminum hydroxide (AH), and benchmarked them to AS01B and AS03-like emulsion-based adjuvants for their potential to enhance RBD immunogenicity in young and aged mice. We found that the AH and CpG adjuvant formulation (AH:CpG) demonstrated the highest enhancement of anti-RBD neutralizing Ab titers in both age groups ([~]80-fold over AH), and protected aged mice from the SARS-CoV-2 challenge. Notably, AH:CpG-adjuvanted RBD vaccine elicited neutralizing Abs against both wild-type SARS-CoV-2 and B.1.351 variant at serum concentrations comparable to those induced by the authorized mRNA BNT162b2 vaccine. AH:CpG induced similar cytokine and chemokine gene enrichment patterns in the draining lymph nodes of both young adult and aged mice and synergistically enhanced cytokine and chemokine production in human young adult and elderly mononuclear cells. These data support further development of AH:CpG-adjuvanted RBD as an affordable vaccine that may be effective across multiple age groups. One Sentence SummaryAlum and CpG enhance SARS-CoV-2 RBD protective immunity, variant neutralization in aged mice and Th1-polarizing cytokine production by human elder leukocytes.

immunology↗

Cellular pathways during spawning induction in the starlet sea anemone Nematostella vectensis

In cnidarians, long-term ecological success relies on sexual reproduction. The sea anemone Nematostella vectensis, which has emerged as an important model organism for developmental studies, can be induced for spawning by temperature elevation and light exposure. To uncover molecular mechanisms and pathways underlying spawning, we characterized the transcriptome of Nematostella females before and during spawning induction. We identified an array of processes involving numerous receptors, circadian clock components, cytoskeleton, and extracellular transcripts that are upregulated upon spawning induction. Concurrently, processes related to the cell cycle, fatty acid metabolism, and other housekeeping functions are downregulated. Real-time qPCR revealed that light exposure has a minor effect on expression levels of most examined transcripts, implying that temperature change is a stronger inducer for spawning in Nematostella. Our findings reveal the mechanisms that may enable the mesenteries to serve as a gonad-like tissue for the developing oocytes and expand our understanding of sexual reproduction in cnidarians. Summary statementAnalysis of transcriptional changes during spawning induction in Nematostella vectensis, revealed upregulation of processes related to signal perception and cytoskeleton rearrangement and downregulation of fatty acid metabolism and housekeeping processes.

ecology↗

Proteomics on longitudinal serum samples differentiates localized and disseminated Lyme disease

Lyme disease (LD) is the most prevalent vector-borne disease in North America, with ~300,000 new cases annually in the USA alone. LD is most often recognized by the appearance of the skin lesion erythema migrans (EM) at the tick bite site but also can present with signs of disseminated infection manifesting as multiple EM lesions and/or involvement of the heart, nervous system or joints. In this study, we examined the serum proteome of study participants presenting with either a single EM (localized LD) or early disseminated infection (disseminated LD). Samples collected at the time of diagnosis and at convalescent time points were assessed using our in-house developed MStern blotting-based serum proteomics platform. After technical validation of our platform, the temporal analysis from diagnosis to clinical resolution of the infection demonstrates LD stage-associated pathways activation such as a temporary upregulation of acute phase response specific to the participants with disseminated LD. In addition, we identified the members of the serum amyloid A protein family as potentially promising candidate biomarkers to identify those with disseminated LD. The results of this pilot study demonstrate the feasibility of using our time- and cost-effective sample sparing MStern blotting-based serum proteomics platform to efficiently interrogate proteome changes over time in those suffering infections such as LD. These observations establish a new approach to human serum proteomics, provide fresh insight into the host immune responses associated with disease severity (localized versus disseminated infection) and suggest novel biomarker candidate panels for LD stages. ImportanceWe investigated the proteome changes of Borrelia burgdorferi-infected participants with either a single erythema migrans or early disseminated Lyme disease infection. Using our in-house time-and cost-effective proteomics platform, the temporal analysis from diagnosis to clinical resolution of the infection shows a temporary upregulation of the acute phase response specific to the participants with disseminated infection. Finally, specific protein panels were identified as possible biomarker candidates to categorize those having an initial diagnosis of disseminated manifestation using a reference cohort of acute localized infection and a clinically resolved convalescent phase disease samples from the same Lyme disease participants.

immunology↗

Efficient 5-OP-RU-induced enrichment of Mucosal-associated invariant T cells in the murine lung does not enhance control of aerosol Mycobacterium tuberculosis infection.

Mucosal-associated invariant T (MAIT) cells are an innate-like T cell subset in mammals that recognize microbial vitamin B metabolites presented by the evolutionarily conserved MHC I-related molecule MR1. Emerging data suggest that MAIT cells may be an attractive target for vaccine-induced protection against bacterial infections because of their rapid cytotoxic responses at mucosal services to a widely conserved bacterial ligand. In this study, we tested whether a MAIT cell priming strategy could protect against aerosol Mycobacterium tuberculosis (Mtb) infection in mice. Intranasal co-stimulation with the lipopeptide TLR 2/6 agonist, Pam2Cys (P2C), and the synthetic MR1 ligand, 5-OP-RU, resulted in robust expansion of MAIT cells in lung. Although MAIT cell priming significantly enhanced MAIT cell activation and expansion early after Mtb challenge, these MAIT cells did not restrict Mtb bacterial load. MAIT cells were depleted later in infection, with decreased detection of granzyme B+ and IFN{gamma}+ MAIT cells relative to uninfected P2C/5-OP-RU-treated mice. Decreasing the infectious inoculum, varying the time between priming and aerosol infection, and testing MAIT cell priming in NOS2 deficient mice all failed to reveal an effect of P2C/5-OP-RU induced MAIT cells on Mtb control. We conclude that intranasal MAIT cell priming in mice induces early MAIT cell activation and expansion after Mtb exposure, without attenuating M. tuberculosis growth, suggesting that Mtb evades MAIT cell-dependent immunity.

immunology↗

Early birds, late owls, and the ecological role of intra-population chronotype variation

While the molecular mechanisms underlying variation in chronotypes within populations have been studied extensively, the ultimate selective forces governing it are poorly understood. The proximate cause is variation in clock genes and protein expression, which produces variation in tau (period length of the circadian clock), with early individuals having shorter tau. We studied within-population variation in foraging activity times of two Acomys species in the field. This variation manifested in a regular and consistent sequence of individual foraging activity that is positively and strongly correlated with variation in tau. Thus, variation in circadian clock period length (tau) appears to be the mechanism underlying the regular pattern of intraspecific temporal partitioning. Late chronotypes also spent more time torpid than earlier ones, suggesting an energetic cost to this strategy and possible tradeoffs. We suggest that variation in tau is an adaptive mechanism to reduce competition between individuals within a population.

ecology↗

Lymph node follicle formation and vaccination responses reconstituted in vitro in a human Organ Chip

Lymphoid follicles (LFs) are responsible for generation of adaptive immune responses in secondary lymphoid organs and form ectopically during chronic inflammation. A human model of LF formation would provide a tool to understand LF development and an alternative to non-human primate models for preclinical evaluation of vaccines. Here, we show that primary human blood B- and T-lymphocytes autonomously assemble into ectopic LFs when cultured in a three-dimensional (3D) extracellular matrix gel within an organ-on-a-chip microfluidic device. Dynamic fluid flow is required for LF formation and prevention of lymphocyte autoactivation. These germinal center-like LFs contain B cells expressing Activation-Induced Cytidine Deaminase and exhibit plasma cell (PC) differentiation upon activation. To explore their utility for vaccine testing, autologous monocyte-derived dendritic cells were integrated into LF Chips. The human LF chips demonstrated improved antibody responses to split virion influenza vaccination compared to 2D cultures, which were enhanced by addition of a squalene-in-water emulsion adjuvant, and this was accompanied by increases in LF size and number. When inoculated with commercial influenza vaccine, PC formation and production of anti-hemagglutinin IgG were observed, as well as secretion of cytokines similar to those observed in vaccinated humans over clinically relevant timescales.

immunology↗

Human colon-on-a-chip enables continuous in vitro analysis of colon mucus layer accumulation and physiology

Background & AimsThe mucus layer in the human colon protects against commensal bacteria and pathogens, and defects in its unique bilayered structure contribute to intestinal disorders, such as ulcerative colitis. However, our understanding of colon physiology is limited by the lack of in vitro models that replicate human colonic mucus layer structure and function. Here, we investigated if combining organ-on-a-chip and organoid technologies can be leveraged to develop a human-relevant in vitro model of colon mucus physiology. MethodsA human colon-on-a-chip (Colon Chip) microfluidic device lined by primary patient-derived colonic epithelial cells was used to recapitulate mucus bilayer formation, and to visualize mucus accumulation in living cultures non-invasively. ResultsThe Colon Chip supports spontaneous goblet cell differentiation and accumulation of a mucus bilayer with impenetrable and penetrable layers, and a thickness similar to that observed in human colon, while maintaining a subpopulation of proliferative epithelial cells. Live imaging of the mucus layer formation on-chip revealed that stimulation of the colonic epithelium with prostaglandin E2, which is elevated during inflammation, causes rapid mucus volume expansion via an NKCC1 ion channel-dependent increase in its hydration state, but no increase in de novo mucus secretion. ConclusionThis study is the first to demonstrate production of colonic mucus with a physiologically relevant bilayer structure in vitro, which can be analyzed in real-time non-invasively. The Colon Chip may offer a new preclinical tool to analyze the role of mucus in human intestinal homeostasis as well as diseases, such as ulcerative colitis and cancer.

cell biology↗

Analysis of common and rare VPS13C variants in late onset Parkinson disease

ObjectiveWe aimed to study the role of coding VPS13C variants in a large cohort of late-onset PD (LOPD) patients.\n\nMethodsVPS13C and its untranslated regions were sequenced using targeted next-generation sequencing in 1,567 PD patients and 1,667 controls from 3 cohorts. Association tests of rare potential homozygous and compound heterozygous variants and burden tests for rare heterozygous variants were performed. Common variants were analyzed using logistic regression adjusted for age and sex in each of the cohorts, followed by a meta-analysis.\n\nResultsNo bi-allelic carriers of rare VPS13C variants were found among patients and two carriers of compound heterozygous variants were found in two controls. There was no statistically significant burden of rare (MAF<1%) or very rare (MAF<0.1%) coding VPS13C variants in PD. A VPS13C haplotype including the p.R153H-p.I398I-p.I1132V-p.Q2376Q variants was nominally associated with a reduced risk for PD (meta-analysis of the tagging SNP p.I1132V (OR=0.48, 95%CI=0.28-0.82, p=0.0052). This haplotype was not in linkage disequilibrium (LD) with the known genome-wide association study (GWAS) top hit.\n\nConclusionsOur results do not support a role for rare heterozygous or bi-allelic VPS13C variants in LOPD. Additional genetic replication and functional studies are needed to examine the role of the haplotype identified here associated with reduced risk for PD.

genetics↗

Analysis of 19 Heliconiine Butterflies Shows Rapid TE-based Diversification and Multiple SINE Births and Deaths

Transposable elements (TEs) play major roles in the evolution of genome structure and function. However, because of their repetitive nature, they are difficult to annotate and discovering the specific roles they may play in a lineage can be a daunting task. Heliconiine butterflies are models for the study of multiple evolutionary processes including phenotype evolution and hybridization. We attempted to determine how TEs may play a role in the diversification of genomes within this clade by performing a detailed examination of TE content and accumulation in 19 species whose genomes were recently sequenced. We found that TE content has diverged substantially and rapidly in the time since several subclades shared a common ancestor with each lineage harboring a unique TE repertoire. Several novel SINE lineages have been established that are restricted to a subset of species. Furthermore, the previously described SINE, Metulj, appears to have gone extinct in two subclades while expanding to significant numbers in others. Finally, a burst of TE origination corresponds temporally to a burst of speciation in the clade, potentially providing support to hypotheses that TEs are drivers of genotypic and phenotypic diversification. This diversity in TE content and activity has the potential to impact how heliconiine butterflies continue to evolve and diverge.

evolutionary biology↗

The TLR5 agonist flagellin modifies phenotypical and enhances functional activation of lung mucosal antigen presenting cells in neonatal mice

Intranasal mucosal vaccines are of interest in that they may induce protective mucosal immune responses. Activation of lung antigen presenting cells (APCs), a phenotyoically and functionally heterogeneous cell population located at distinct mucosal sites, may be key to the immunogenicity of such vaccines. Characterizing responsiveness of newborn lung APCs to adjuvants may inform design of efficacious intranasal vaccines for early life, when most infections occur. We characterized APCs from neonatal (<7 days of life) and adult (6-8 weeks of age) mice. Neonatal mice displayed a relatively high abundance of alveolar macrophages (AMs), with lower percentages of plasmacytoid dendritic cells (pDCs), CD103+ (cDC1) and CD11b+ (cDC2) DCs. Furthermore, neonatal CD103+ and CD11b+ DC subsets demonstrated an inverse expression of maturation markers as compared to adult mice. Upon stimulation of lung APC subsets with a panel of pattern recognition receptor (PRR), including TLR and STING, agonists, CD11c+ enriched cells from neonatal and adult mice lungs demonstrated distinct maturation profiles. The TLR5 ligand, flagellin, was most effective at activating neonatal lung APCs, inducing significantly higher expression of maturation markers on CD103+ (cDC1) and CD11b+ (cDC2) subsets. Intranasal administration of flagellin induced a distinct migration of CD103+ and CD11b+ DC subsets to the mediastinal lymph nodes (mLNs) of neonatal mice. Overall, these findings highlight age specific differences in the maturation and responsiveness of lung APC subsets to different PRR agonists. The unique efficacy of flagellin in enhancing lung APC activity suggests that it may serve as an effective adjuvant for early life mucosal vaccines.

immunology↗

12h-clock control of central dogma information flow by XBP1s

Our group recently discovered a cell-autonomous mammalian 12h-clock regulating physiological unfolded protein response. Xbp1s ablation impairs 12h-transcript oscillations in vitro, and we now show liver-specific deletion of XBP1s globally impaired murine 12h-transcriptome, but not the circadian rhythms in vivo. XBP1s-dependent 12h-transcriptome is enriched for transcription, mRNA processing, ribosome biogenesis, translation, and protein ER-Golgi processing/sorting in a temporal order consistent with the progressive molecular processing sequence described by the central dogma information flow (CEDIF). The 12h-rhythms of CEDIF are cell-autonomous and evolutionarily conserved in circatidal marine animals. Mechanistically, we found the motif stringency of promoter XBP1s binding sites, but not necessarily XBP1s expression, dictates its ability to drive 12h-rhythms of transcription and further identified GABP as putative novel transcriptional regulator of 12h-clock. We hypothesize the 12h-rhythms of CEDIF allows rush hours gene expression and processing, with the particular genes processed at each rush hour regulated by circadian and/or tissue specific pathways.

systems biology↗