1. |
- Berglund, Rasmus, et al.
(author)
-
Microglial autophagy-associated phagocytosis is essential for recovery from neuroinflammation
- 2020
-
In: Science Immunology. - Stockholm : Karolinska Institutet, Dept of Clinical Neuroscience. - 2470-9468.
-
Journal article (peer-reviewed)abstract
- Multiple sclerosis (MS) is a leading cause of incurable progressive disability in young adults caused by inflammation and neurodegeneration in the central nervous system (CNS). The capacity of microglia to clear tissue debris is essential for maintaining and restoring CNS homeostasis. This capacity diminishes with age, and age strongly associates with MS disease progression, although the underlying mechanisms are still largely elusive. Here, we demonstrate that the recovery from CNS inflammation in a murine model of MS is dependent on the ability of microglia to clear tissue debris. Microglia-specific deletion of the autophagy regulator Atg7, but not the canonical macroautophagy protein Ulk1, led to increased intracellular accumulation of phagocytosed myelin and progressive MS-like disease. This impairment correlated with a microglial phenotype previously associated with neurodegenerative pathologies. Moreover, Atg7-deficient microglia showed notable transcriptional and functional similarities to microglia from aged wild-type mice that were also unable to clear myelin and recover from disease. In contrast, induction of autophagy in aged mice using the disaccharide trehalose found in plants and fungi led to functional myelin clearance and disease remission. Our results demonstrate that a noncanonical form of autophagy in microglia is responsible for myelin degradation and clearance leading to recovery from MS-like disease and that boosting this process has a therapeutic potential for age-related neuroinflammatory conditions.
|
|
2. |
|
|
3. |
|
|
4. |
- Bastard, P, et al.
(author)
-
Vaccine breakthrough hypoxemic COVID-19 pneumonia in patients with auto-Abs neutralizing type I IFNs
- 2022
-
In: Science immunology. - : American Association for the Advancement of Science (AAAS). - 2470-9468. ; 78:7490, s. eabp8966-
-
Journal article (peer-reviewed)abstract
- Life-threatening ‘breakthrough’ cases of critical COVID-19 are attributed to poor or waning antibody response to the SARS-CoV-2 vaccine in individuals already at risk. Pre-existing autoantibodies (auto-Abs) neutralizing type I IFNs underlie at least 15% of critical COVID-19 pneumonia cases in unvaccinated individuals; however, their contribution to hypoxemic breakthrough cases in vaccinated people remains unknown. Here, we studied a cohort of 48 individuals (age 20-86 years) who received 2 doses of an mRNA vaccine and developed a breakthrough infection with hypoxemic COVID-19 pneumonia 2 weeks to 4 months later. Antibody levels to the vaccine, neutralization of the virus, and auto-Abs to type I IFNs were measured in the plasma. Forty-two individuals had no known deficiency of B cell immunity and a normal antibody response to the vaccine. Among them, ten (24%) had auto-Abs neutralizing type I IFNs (aged 43-86 years). Eight of these ten patients had auto-Abs neutralizing both IFN-α2 and IFN-ω, while two neutralized IFN-ω only. No patient neutralized IFN-β. Seven neutralized 10 ng/mL of type I IFNs, and three 100 pg/mL only. Seven patients neutralized SARS-CoV-2 D614G and the Delta variant (B.1.617.2) efficiently, while one patient neutralized Delta slightly less efficiently. Two of the three patients neutralizing only 100 pg/mL of type I IFNs neutralized both D61G and Delta less efficiently. Despite two mRNA vaccine inoculations and the presence of circulating antibodies capable of neutralizing SARS-CoV-2, auto-Abs neutralizing type I IFNs may underlie a significant proportion of hypoxemic COVID-19 pneumonia cases, highlighting the importance of this particularly vulnerable population.
|
|
5. |
- Bianchini, F, et al.
(author)
-
Human neutralizing antibodies to cold linear epitopes and subdomain 1 of the SARS-CoV-2 spike glycoprotein
- 2023
-
In: Science immunology. - : American Association for the Advancement of Science (AAAS). - 2470-9468. ; 8:81, s. eade0958-
-
Journal article (peer-reviewed)abstract
- Emergence of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) variants diminishes the efficacy of vaccines and antiviral monoclonal antibodies. Continued development of immunotherapies and vaccine immunogens resilient to viral evolution is therefore necessary. Using coldspot-guided antibody discovery, a screening approach that focuses on portions of the virus spike glycoprotein that are both functionally relevant and averse to change, we identified human neutralizing antibodies to highly conserved viral epitopes. Antibody fp.006 binds the fusion peptide and cross-reacts against coronaviruses of the four genera, including the nine human coronaviruses, through recognition of a conserved motif that includes the S2′ site of proteolytic cleavage. Antibody hr2.016 targets the stem helix and neutralizes SARS-CoV-2 variants. Antibody sd1.040 binds to subdomain 1, synergizes with antibody rbd.042 for neutralization, and, similar to fp.006 and hr2.016, protects mice expressing human angiotensin-converting enzyme 2 against infection when present as a bispecific antibody. Thus, coldspot-guided antibody discovery reveals donor-derived neutralizing antibodies that are cross-reactive with Orthocoronavirinae, including SARS-CoV-2 variants.
|
|
6. |
- Bianchini, F, et al.
(author)
-
Human neutralizing antibodies to cold linear epitopes and subdomain 1 of the SARS-CoV-2 spike glycoprotein
- 2023
-
In: Science immunology. - : American Association for the Advancement of Science (AAAS). - 2470-9468. ; 8:81, s. eade0958-
-
Journal article (peer-reviewed)abstract
- Emergence of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) variants diminishes the efficacy of vaccines and antiviral monoclonal antibodies. Continued development of immunotherapies and vaccine immunogens resilient to viral evolution is therefore necessary. Using coldspot-guided antibody discovery, a screening approach that focuses on portions of the virus spike glycoprotein that are both functionally relevant and averse to change, we identified human neutralizing antibodies to highly conserved viral epitopes. Antibody fp.006 binds the fusion peptide and cross-reacts against coronaviruses of the four genera, including the nine human coronaviruses, through recognition of a conserved motif that includes the S2′ site of proteolytic cleavage. Antibody hr2.016 targets the stem helix and neutralizes SARS-CoV-2 variants. Antibody sd1.040 binds to subdomain 1, synergizes with antibody rbd.042 for neutralization, and, similar to fp.006 and hr2.016, protects mice expressing human angiotensin-converting enzyme 2 against infection when present as a bispecific antibody. Thus, coldspot-guided antibody discovery reveals donor-derived neutralizing antibodies that are cross-reactive with Orthocoronavirinae, including SARS-CoV-2 variants.
|
|
7. |
|
|
8. |
|
|
9. |
|
|
10. |
|
|
11. |
|
|
12. |
|
|
13. |
- Gribonika, Inta, et al.
(author)
-
Peyer's patch TH17 cells are dispensable for gut IgA responses to oral immunization.
- 2022
-
In: Science immunology. - : American Association for the Advancement of Science (AAAS). - 2470-9468. ; 7:73
-
Journal article (peer-reviewed)abstract
- T helper 17 (TH17) cells located at the Peyer's patch (PP) inductive site and at the lamina propria effector site of the intestinal immune system are responsive to both pathogenic and commensal bacteria. Their plasticity to convert into follicular helper T (TFH) cells has been proposed to be central to gut immunoglobulin A (IgA) responses. Here, we used an IL-17A fate reporter mouse and an MHC-II tetramer to analyze antigen-specific CD4+ T cell subsets and isolate them for single-cell RNA sequencing after oral immunization with cholera toxin and ovalbumin. We found a TFH-dominated response with only rare antigen-specific TH17 cells (<8%) in the PP. A clonotypic analysis provided little support that clonotypes were shared between TFH and TH17 cells, arguing against TH17 plasticity as a major contributor to TFH differentiation. Two mouse models of TH17 deficiency confirmed that gut IgA responses to oral immunization do not require TH17 cells, with CD4CreRorcfl/fl mice exhibiting normal germinal centers in PP and unperturbed total IgA production in the intestine.
|
|
14. |
- Hait, A. S., et al.
(author)
-
Defects in LC3B2 and ATG4A underlie HSV2 meningitis and reveal a critical role for autophagy in antiviral defense in humans
- 2020
-
In: Science Immunology. - : American Association for the Advancement of Science (AAAS). - 2470-9468. ; 5:54
-
Journal article (peer-reviewed)abstract
- Recurrent herpesvirus infections can manifest in different forms of disease, including cold sores, genital herpes, and encephalitis. There is an incomplete understanding of the genetic and immunological factors conferring susceptibility to recurrent herpes simplex virus 2 (HSV2) infection in the central nervous system (CNS). Here, we describe two adult patients with recurrent HSV2 lymphocytic Mollaret's meningitis that each carry a rare monoallelic variant in the autophagy proteins ATG4A or LC3B2. HSV2-activated autophagy was abrogated in patient primary fibroblasts, which also exhibited significantly increased viral replication and enhanced cell death. HSV2 antigen was captured in autophagosomes of infected cells, and genetic inhibition of autophagy by disruption of autophagy genes, including ATG4A and LC3B2, led to enhanced viral replication and cell death in primary fibroblasts and a neuroblastoma cell line. Activation of autophagy by HSV2 was sensitive to ultraviolet (UV) irradiation of the virus and inhibited in the presence of acyclovir, but HSV2-induced autophagy was independent of the DNA-activated STING pathway. Reconstitution of wild-type ATG4A and LC3B2 expression using lentiviral gene delivery or electroporation of in vitro transcribed mRNA into patient cells restored virus-induced autophagy and the ability to control HSV2 replication. This study describes a previously unknown link between defective autophagy and an inborn error of immunity that can lead to increased susceptibility to HSV2 infection, suggesting an important role for autophagy in antiviral immunity in the CNS.
|
|
15. |
|
|
16. |
|
|
17. |
|
|
18. |
|
|
19. |
|
|
20. |
- Joeris, Thorsten, et al.
(author)
-
Intestinal cDC1 drive cross-tolerance to epithelial-derived antigen via induction of FoxP3+CD8+ Tregs
- 2021
-
In: Science Immunology. - : American Association for the Advancement of Science (AAAS). - 2470-9468. ; 6:60
-
Journal article (peer-reviewed)abstract
- Although CD8+ T cell tolerance to tissue-specific antigen (TSA) is essential for host homeostasis, the mechanisms underlying peripheral cross-tolerance and whether they may differ between tissue sites remain to be fully elucidated. Here, we demonstrate that peripheral cross-tolerance to intestinal epithelial cell (IEC)–derived antigen involves the generation and suppressive function of FoxP3+CD8+ T cells. FoxP3+CD8+ Treg generation was dependent on intestinal cDC1, whose absence led to a break of tolerance and epithelial destruction. Mechanistically, intestinal cDC1-derived PD-L1, TGFβ, and retinoic acid contributed to the generation of gut-tropic CCR9+CD103+FoxP3+CD8+ Tregs. Last, CD103-deficient CD8+ T cells lacked tolerogenic activity in vivo, indicating a role for CD103 in FoxP3+CD8+ Treg function. Our results describe a role for FoxP3+CD8+ Tregs in cross-tolerance in the intestine for which development requires intestinal cDC1.
|
|
21. |
- Kaku, Chengzi I., et al.
(author)
-
Recall of preexisting cross-reactive B cell memory after Omicron BA.1 breakthrough infection
- 2022
-
In: Science immunology. - : American Association for the Advancement of Science. - 2470-9468. ; 7:73
-
Journal article (peer-reviewed)abstract
- Understanding immune responses after severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) breakthrough infection will facilitate the development of next-generation vaccines. Here, we profiled spike (S)-specific B cell responses after Omicron/BA.1 infection in messenger RNA-vaccinated donors. The acute antibody response was characterized by high levels of somatic hypermutation and a bias toward recognition of ancestral SARS-CoV-2 strains, suggesting the early activation of vaccine-induced memory B cells. BA.1 breakthrough infection induced a shift in B cell immunodominance hierarchy from the S2 subunit, which is highly conserved across SARS-CoV-2 variants of concern (VOCs), and toward the antigenically variable receptor binding domain (RBD). A large proportion of RBD-directed neutralizing antibodies isolated from BA.1 breakthrough infection donors displayed convergent sequence features and broadly recognized SARS-CoV-2 VOCs. Together, these findings provide insights into the role of preexisting immunity in shaping the B cell response to heterologous SARS-CoV-2 variant exposure.
|
|
22. |
- Karlsson, AC, et al.
(author)
-
The known unknowns of T cell immunity to COVID-19
- 2020
-
In: Science immunology. - : American Association for the Advancement of Science (AAAS). - 2470-9468. ; 5:53
-
Journal article (peer-reviewed)abstract
- Unanswered questions remain about the contributions of T cell immunity to protective and dysfunctional responses in COVID-19.
|
|
23. |
- Kokkinou, Efthymia, et al.
(author)
-
CD45RA(+)CD62L(-) ILCs in human tissues represent a quiescent local reservoir for the generation of differentiated ILCs
- 2022
-
In: Science immunology. - : AMER ASSOC ADVANCEMENT SCIENCE. - 2470-9468. ; 7:70
-
Journal article (peer-reviewed)abstract
- Innate lymphoid cells (ILCs) are highly plastic and predominantly mucosal tissue-resident cells that contribute to both homeostasis and inflammation depending on the microenvironment. The discovery of naive-like ILCs suggests an ILC differentiation process that is akin to naive T cell differentiation. Delineating the mechanisms that underlie ILC differentiation in tissues is crucial for understanding ILC biology in health and disease. Here, we showed that tonsillar ILCs expressing CD45RA lacked proliferative activity, indicative of cellular quiescence. CD62L distinguished two subsets of CD45RA(+) ILCs. CD45RA(+)CD62L(+) ILCs (CD62L(+) ILCs) resembled circulating naive ILCs because they lacked the transcriptional, metabolic, epigenetic, and cytokine production signatures of differentiated ILCs. CD45RA(+)CD62L(-) ILCs (CD62L(-) ILCs) were epigenetically similar to CD62L(+) ILCs but showed a transcriptional, metabolic, and cytokine production signature that was more akin to differentiated ILCs. CD62L(+) and CD62L(-) ILCs contained uni- and multipotent precursors of ILC1s/NK cells and ILC3s. Differentiation of CD62L(+) and CD62L(-) ILCs led to metabolic reprogramming including up-regulation of genes associated with glycolysis, which was needed for their effector functions after differentiation. CD62L(-) ILCs with preferential differentiation capacity toward IL-22-producing ILC3s accumulated in the inflamed mucosa of patients with inflammatory bowel disease. These data suggested distinct differentiation potential of CD62L(+) and CD62L(-) ILCs between tissue microenvironments and identified that manipulation of these cells is a possible approach to restore tissue-immune homeostasis.
|
|
24. |
- Krishnaswamy, Jayendra Kumar, et al.
(author)
-
Migratory CD11b+ conventional dendritic cells induce T follicular helper cell-dependent antibody responses.
- 2017
-
In: Science immunology. - : American Association for the Advancement of Science (AAAS). - 2470-9468. ; 2:18
-
Journal article (peer-reviewed)abstract
- T follicular helper (Tfh) cells are a subset of CD4+ T cells that promote antibody production during vaccination. Conventional dendritic cells (cDCs) efficiently prime Tfh cells; however, conclusions regarding which cDC instructs Tfh cell differentiation have differed between recent studies. We found that these discrepancies might exist because of the unusual sites used for immunization in murine models, which differentially bias which DC subsets access antigen. We used intranasal immunization as a physiologically relevant route of exposure that delivers antigen to all tissue DC subsets. Using a combination of mice in which the function of individual DC subsets is impaired and different antigen formulations, we determined that CD11b+ migratory type 2 cDCs (cDC2s) are necessary and sufficient for Tfh induction. DC-specific deletion of the guanine nucleotide exchange factor DOCK8 resulted in an isolated loss of CD11b+ cDC2, but not CD103+ cDC1, migration to lung-draining lymph nodes. Impaired cDC2 migration or development in DC-specific Dock8 or Irf4 knockout mice, respectively, led to reduced Tfh cell priming, whereas loss of CD103+ cDC1s in Batf3-/- mice did not. Loss of cDC2-dependent Tfh cell priming impaired antibody-mediated protection from live influenza virus challenge. We show that migratory cDC2s uniquely carry antigen into the subanatomic regions of the lymph node where Tfh cell priming occurs-the T-B border. This work identifies the DC subset responsible for Tfh cell-dependent antibody responses, particularly when antigen dose is limiting or is encountered at a mucosal site, which could ultimately inform the formulation and delivery of vaccines.
|
|
25. |
- Kvedaraite, E, et al.
(author)
-
Human dendritic cells in cancer
- 2022
-
In: Science immunology. - 2470-9468. ; 7:70, s. eabm9409-
-
Journal article (peer-reviewed)
|
|
26. |
- Kvedaraite, E, et al.
(author)
-
Human dendritic cells in cancer
- 2022
-
In: Science immunology. - : American Association for the Advancement of Science (AAAS). - 2470-9468. ; 7:70, s. eabm9409-
-
Journal article (peer-reviewed)abstract
- Dendritic cells (DCs) are professional antigen-presenting cells, orchestrating innate and adaptive immunity during infections, autoimmune diseases, and malignancies. Since the discovery of DCs almost 50 years ago, our understanding of their biology in humans has increased substantially. Here, we review both antitumor and tolerogenic DC responses in cancer and discuss lineage-specific contributions by their functionally specialized subsets, including the conventional DC (cDC) subsets cDC1 and cDC2, the newly described DC3, and the plasmacytoid DCs (pDCs), focusing on the human setting. In addition, we review the lineage-unrestricted “mature DCs enriched in immunoregulatory molecules” (mregDC) state recently described across different human tumors.
|
|
27. |
- Kvedaraite, E, et al.
(author)
-
Notch-dependent cooperativity between myeloid lineages promotes Langerhans cell histiocytosis pathology
- 2022
-
In: Science immunology. - : American Association for the Advancement of Science (AAAS). - 2470-9468. ; 7:78, s. eadd3330-
-
Journal article (peer-reviewed)abstract
- Langerhans cell histiocytosis (LCH) is a potentially fatal neoplasm characterized by the aberrant differentiation of mononuclear phagocytes, driven by mitogen-activated protein kinase (MAPK) pathway activation. LCH cells may trigger destructive pathology yet remain in a precarious state finely balanced between apoptosis and survival, supported by a unique inflammatory milieu. The interactions that maintain this state are not well known and may offer targets for intervention. Here, we used single-cell RNA-seq and protein analysis to dissect LCH lesions, assessing LCH cell heterogeneity and comparing LCH cells with normal mononuclear phagocytes within lesions. We found LCH discriminatory signatures pointing to senescence and escape from tumor immune surveillance. We also uncovered two major lineages of LCH with DC2- and DC3/monocyte-like phenotypes and validated them in multiple pathological tissue sites by high-content imaging. Receptor-ligand analyses and lineage tracing in vitro revealed Notch-dependent cooperativity between DC2 and DC3/monocyte lineages during expression of the pathognomonic LCH program. Our results present a convergent dual origin model of LCH with MAPK pathway activation occurring before fate commitment to DC2 and DC3/monocyte lineages and Notch-dependent cooperativity between lineages driving the development of LCH cells.
|
|
28. |
|
|
29. |
- Lönnberg, Tapio, et al.
(author)
-
Single-cell RNA-seq and computational analysis using temporal mixture modelling resolves Th1/Tfh fate bifurcation in malaria
- 2017
-
In: Science immunology. - : American Association for the Advancement of Science (AAAS). - 2470-9468. ; 2:9
-
Journal article (peer-reviewed)abstract
- Differentiation of naïve CD4(+) T cells into functionally distinct T helper subsets is crucial for the orchestration of immune responses. Due to extensive heterogeneity and multiple overlapping transcriptional programs in differentiating T cell populations, this process has remained a challenge for systematic dissection in vivo. By using single-cell transcriptomics and computational analysis using a temporal mixtures of Gaussian processes model, termed GPfates, we reconstructed the developmental trajectories of Th1 and Tfh cells during blood-stage Plasmodium infection in mice. By tracking clonality using endogenous TCR sequences, we first demonstrated that Th1/Tfh bifurcation had occurred at both population and single-clone levels. Next, we identified genes whose expression was associated with Th1 or Tfh fates, and demonstrated a T-cell intrinsic role for Galectin-1 in supporting a Th1 differentiation. We also revealed the close molecular relationship between Th1 and IL-10-producing Tr1 cells in this infection. Th1 and Tfh fates emerged from a highly proliferative precursor that upregulated aerobic glycolysis and accelerated cell cycling as cytokine expression began. Dynamic gene expression of chemokine receptors around bifurcation predicted roles for cell-cell in driving Th1/Tfh fates. In particular, we found that precursor Th cells were coached towards a Th1 but not a Tfh fate by inflammatory monocytes. Thus, by integrating genomic and computational approaches, our study has provided two unique resources, a database www.PlasmoTH.org, which facilitates discovery of novel factors controlling Th1/Tfh fate commitment, and more generally, GPfates, a modelling framework for characterizing cell differentiation towards multiple fates.
|
|
30. |
|
|
31. |
|
|
32. |
|
|
33. |
|
|
34. |
- Niessl, Julia, et al.
(author)
-
Identification of resident memory CD8+ T cells with functional specificity for SARS-CoV-2 in unexposed oropharyngeal lymphoid tissue
- 2021
-
In: Science immunology. - : American Association for the Advancement of Science (AAAS). - 2470-9468. ; 6:64
-
Journal article (peer-reviewed)abstract
- Cross-reactive CD4+ T cells that recognize severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) are more commonly detected in the peripheral blood of unexposed individuals compared with SARS-CoV-2–reactive CD8+ T cells. However, large numbers of memory CD8+ T cells reside in tissues, feasibly harboring localized SARS-CoV-2–specific immune responses. To test this idea, we performed a comprehensive functional and phenotypic analysis of virus-specific T cells in tonsils, a major lymphoid tissue site in the upper respiratory tract, and matched peripheral blood samples obtained from children and adults before the emergence of COVID-19 (coronavirus disease 2019). We found that SARS-CoV-2–specific memory CD4+ T cells could be found at similar frequencies in the tonsils and peripheral blood in unexposed individuals, whereas functional SARS-CoV-2–specific memory CD8+ T cells were almost only detectable in the tonsils. Tonsillar SARS-CoV-2–specific memory CD8+ T cells displayed a follicular homing and tissue-resident memory phenotype, similar to tonsillar Epstein-Barr virus–specific memory CD8+ T cells, but were functionally less potent than other virus-specific memory CD8+ T cell responses. The presence of preexisting tissue-resident memory CD8+ T cells in unexposed individuals could potentially enable rapid sentinel immune responses against SARS-CoV-2.
|
|
35. |
|
|
36. |
- Perez-Shibayama, Christian, et al.
(author)
-
Type I interferon signaling in fibroblastic reticular cells prevents exhaustive activation of antiviral CD8+ T cells.
- 2020
-
In: Science immunology. - 2470-9468. ; 5:51
-
Journal article (peer-reviewed)abstract
- Fibroblastic reticular cells (FRCs) are stromal cells that actively promote the induction of immune responses by coordinating the interaction of innate and adaptive immune cells. However, whether and to which extent immune cell activation is determined by lymph node FRC reprogramming during acute viral infection has remained unexplored. Here, we genetically ablated expression of the type I interferon-α receptor (Ifnar) in Ccl19-Cre+ cells and found that sensing of type I interferon imprints an antiviral state in FRCs and thereby preserves myeloid cell composition in lymph nodes of naive mice. During localized lymphocytic choriomeningitis virus infection, IFNAR signaling precipitated profound phenotypic adaptation of all FRC subsets enhancing antigen presentation, chemokine-driven immune cell recruitment, and immune regulation. The IFNAR-dependent shift of all FRC subsets toward an immunostimulatory state reduced exhaustive CD8+ T cell activation. In sum, these results unveil intricate circuits underlying type I IFN sensing in lymph node FRCs that enable protective antiviral immunity.
|
|
37. |
- Pröbstel, Anne-Katrin, et al.
(author)
-
Gut microbiota-specific IgA+ B cells traffic to the CNS in active multiple sclerosis
- 2020
-
In: Science immunology. - : American Association for the Advancement of Science. - 2470-9468. ; 5:53
-
Journal article (peer-reviewed)abstract
- Changes in gut microbiota composition and a diverse role of B cells have recently been implicated in multiple sclerosis (MS), a central nervous system (CNS) autoimmune disease. Immunoglobulin A (IgA) is a key regulator at the mucosal interface. However, whether gut microbiota shape IgA responses and what role IgA+ cells have in neuroinflammation are unknown. Here, we identify IgA-bound taxa in MS and show that IgA-producing cells specific for MS-associated taxa traffic to the inflamed CNS, resulting in a strong, compartmentalized IgA enrichment in active MS and other neuroinflammatory diseases. Unlike previously characterized polyreactive anti-commensal IgA responses, CNS IgA cross-reacts with surface structures on specific bacterial strains but not with brain tissue. These findings establish gut microbiota-specific IgA+ cells as a systemic mediator in MS and suggest a critical role of mucosal B cells during active neuroinflammation with broad implications for IgA as an informative biomarker and IgA-producing cells as an immune subset to harness for therapeutic interventions.
|
|
38. |
- Rosa, Fábio F., et al.
(author)
-
Direct reprogramming of fibroblasts into antigen-presenting dendritic cells
- 2018
-
In: Science Immunology. - : American Association for the Advancement of Science (AAAS). - 2470-9468. ; 3:30
-
Journal article (peer-reviewed)abstract
- Ectopic expression of transcription factors has been used to reprogram differentiated somatic cells toward pluripotency or to directly reprogram them to other somatic cell lineages. This concept has been explored in the context of regenerative medicine. Here, we set out to generate dendritic cells (DCs) capable of presenting antigens from mouse and human fibroblasts. By screening combinations of 18 transcription factors that are expressed in DCs, we have identified PU.1, IRF8, and BATF3 transcription factors as being sufficient to reprogram both mouse and human fibroblasts to induced DCs (iDCs). iDCs acquire a conventional DC type 1-like transcriptional program, with features of interferon-induced maturation. iDCs secrete inflammatory cytokines and have the ability to engulf, process, and present antigens to T cells. Furthermore, we demonstrate that murine iDCs generated here were able to cross-present antigens to CD8+ T cells. Our reprogramming system should facilitate better understanding of DC specification programs and serve as a platform for the development of patient-specific DCs for immunotherapy.
|
|
39. |
- Rosa, Fábio F, et al.
(author)
-
Single-cell transcriptional profiling informs efficient reprogramming of human somatic cells to cross-presenting dendritic cells
- 2022
-
In: Science Immunology. - : American Association for the Advancement of Science (AAAS). - 2470-9468. ; 7:69, s. 1-18
-
Journal article (peer-reviewed)abstract
- Type 1 conventional dendritic cells (cDC1s) are rare immune cells critical for the induction of antigen-specific cytotoxic CD8+ T cells, although the genetic program driving human cDC1 specification remains largely unexplored. We previously identified PU.1, IRF8, and BATF3 transcription factors as sufficient to induce cDC1 fate in mouse fibroblasts, but reprogramming of human somatic cells was limited by low efficiency. Here, we investigated single-cell transcriptional dynamics during human cDC1 reprogramming. Human induced cDC1s (hiDC1s) generated from embryonic fibroblasts gradually acquired a global cDC1 transcriptional profile and expressed antigen presentation signatures, whereas other DC subsets were not induced at the single-cell level during the reprogramming process. We extracted gene modules associated with successful reprogramming and identified inflammatory signaling and the cDC1-inducing transcription factor network as key drivers of the process. Combining IFN-γ, IFN-β, and TNF-α with constitutive expression of cDC1-inducing transcription factors led to improvement of reprogramming efficiency by 190-fold. hiDC1s engulfed dead cells, secreted inflammatory cytokines, and performed antigen cross-presentation, key cDC1 functions. This approach allowed efficient hiDC1 generation from adult fibroblasts and mesenchymal stromal cells. Mechanistically, PU.1 showed dominant and independent chromatin targeting at early phases of reprogramming, recruiting IRF8 and BATF3 to shared binding sites. The cooperative binding at open enhancers and promoters led to silencing of fibroblast genes and activation of a cDC1 program. These findings provide mechanistic insights into human cDC1 specification and reprogramming and represent a platform for generating patient-tailored cDC1s, a long-sought DC subset for vaccination strategies in cancer immunotherapy.
|
|
40. |
|
|
41. |
- Sekine, Takuya, et al.
(author)
-
TOX is expressed by exhausted and polyfunctional human effector memory CD8(+) T cells
- 2020
-
In: Science immunology. - : American Association for the Advancement of Science (AAAS). - 2470-9468. ; 5:49
-
Journal article (peer-reviewed)abstract
- CD8(+) T cell exhaustion is a hallmark of many cancers and chronic infections. In mice, T cell factor 1 (TCF-1) maintains exhausted CD8(+) T cell responses, whereas thymocyte selection-associated HMG box (TOX) is required for the epigenetic remodeling and survival of exhausted CD8(+) T cells. However, it has remained unclear to what extent these transcription factors play analogous roles in humans. In this study, we mapped the expression of TOX and TCF-1 as a function of differentiation and specificity in the human CD8(+) T cell landscape. Here, we demonstrate that circulating TOX+ CD8(+) T cells exist in most humans, but that TOX is not exclusively associated with exhaustion. Effector memory CD8(+) T cells generally expressed TOX, whereas naive and early-differentiated memory CD8(+) T cells generally expressed TCF-1. Cytolytic gene and protein expression signatures were also defined by the expression of TOX. In the context of a relentless immune challenge, exhausted HIV-specific CD8(+) T cells commonly expressed TOX, often in clusters with various activation markers and inhibitory receptors, and expressed less TCF-1. However, polyfunctional memory CD8(+) T cells specific for cytomegalovirus (CMV) or Epstein-Barr virus (EBV) also expressed TOX, either with or without TCF-1. A similar phenotype was observed among HIV-specific CD8(+) T cells from individuals who maintained exceptional immune control of viral replication. Collectively, these data demonstrate that TOX is expressed by most circulating effector memory CD8(+) T cell subsets and not exclusively linked to exhaustion.
|
|
42. |
- Siu, Jacqueline H Y, et al.
(author)
-
Two subsets of human marginal zone B cells resolved by global analysis of lymphoid tissues and blood.
- 2022
-
In: Science immunology. - : American Association for the Advancement of Science (AAAS). - 2470-9468. ; 7:69
-
Journal article (peer-reviewed)abstract
- B cells generate antibodies that are essential for immune protection, but their subgroups are poorly defined. Here, we perform undirected deep profiling of B cells in matched human lymphoid tissues from deceased transplant organ donors and blood. In addition to identifying unanticipated features of tissue-based B cell differentiation, we resolve two subsets of marginal zone B (MZB) cells differing in cell surface and transcriptomic profiles, clonal relationships to other subsets, enrichment of genes in the NOTCH pathway, distribution bias within splenic marginal zone microenvironment, and immunoglobulin repertoire diversity and hypermutation frequency. Each subset is present in spleen, gut-associated lymphoid tissue, mesenteric lymph nodes, and blood. MZB cells and the lineage from which they are derived are depleted in lupus nephritis. Here, we show that this depletion is of only one MZB subset. The other remains unchanged as a proportion of total B cells compared with health. Thus, it is important to factor MZB cell heterogeneity into studies of human B cell responses and pathology.
|
|
43. |
- Strunz, B., et al.
(author)
-
Continuous human uterine NK cell differentiation in response to endometrial regeneration and pregnancy
- 2021
-
In: Science Immunology. - : American Association for the Advancement of Science (AAAS). - 2470-9468. ; 6:56
-
Journal article (peer-reviewed)abstract
- Immune cell differentiation is critical for adequate tissue-specific immune responses to occur. Here, we studied differentiation of human uterine natural killer cells (uNK cells). These cells reside in a tissue undergoing constant regeneration and represent the major leukocyte population at the maternal-fetal interface. However, their physiological response during the menstrual cycle and in pregnancy remains elusive. By surface proteome and transcriptome analysis as well as using humanized mice, we identify a differentiation pathway of uNK cells in vitro and in vivo with sequential acquisition of killer cell immunoglobulin-like receptors and CD39. uNK cell differentiation occurred continuously in response to the endometrial regeneration and was driven by interleukin-15. Differentiated uNK cells displayed reduced proliferative capacity and immunomodulatory function including enhanced angiogenic capacity. By studying human uterus transplantation and monozygotic twins, we found that the uNK cell niche could be replenished from circulation and that it was under genetic control. Together, our study uncovers a continuous differentiation pathway of human NK cells in the uterus that is coupled to profound functional changes in response to local tissue regeneration and pregnancy.
|
|
44. |
|
|
45. |
|
|
46. |
- Vanhee, Stijn, et al.
(author)
-
Lin28b controls a neonatal to adult switch in B cell positive selection
- 2019
-
In: Science immunology. - : AMER ASSOC ADVANCEMENT SCIENCE. - 2470-9468. ; 4:39
-
Journal article (peer-reviewed)abstract
- The ability of B-1 cells to become positively selected into the mature B cell pool, despite being weakly self-reactive, has puzzled the field since its initial discovery. Here, we explore changes in B cell positive selection as a function of developmental time by exploiting a link between CD5 surface levels and the natural occurrence of self-reactive B cell receptors (BCRs) in BCR wild-type mice. We show that the heterochronic RNA binding protein Lin28b potentiates a neonatal mode of B cell selection characterized by enhanced overall positive selection in general and the developmental progression of CD5(+) immature B cells in particular. Lin28b achieves this by amplifying the CD19/PI3K/c-Myc positive feedback loop, and ectopic Lin28b expression restores both positive selection and mature B cell numbers in CD19(-/-) adult mice. Thus, the temporally restricted expression of Lin28b relaxes the rules for B cell selection during ontogeny by modulating tonic signaling. We propose that this neonatal mode of B cell selection represents a cell-intrinsic cue to accelerate the de novo establishment of the adaptive immune system and incorporate a layer of natural antibody-mediated immunity throughout life.
|
|
47. |
|
|
48. |
|
|
49. |
- Zhang, Biyan, et al.
(author)
-
Divergent T follicular helper cell requirement for IgA and IgE production to peanut during allergic sensitization
- 2020
-
In: Science Immunology. - : American Association for the Advancement of Science (AAAS). - 2470-9468. ; 5:47
-
Journal article (peer-reviewed)abstract
- Immunoglobulin A (IgA) is the dominant antibody isotype in the gut and has been shown to regulate microbiota. Mucosal IgA is also widely believed to prevent food allergens from penetrating the gut lining. Even though recent work has elucidated how bacteria-reactive IgA is induced, little is known about how IgA to food antigens is regulated. Although IgA is presumed to be induced in a healthy gut at steady state via dietary exposure, our data do not support this premise. We found that daily food exposure only induced low-level, cross-reactive IgA in a minority of mice. In contrast, induction of significant levels of peanut-specific IgA strictly required a mucosal adjuvant. Although induction of peanut-specific IgA required T cells and CD40L, it was T follicular helper (TFH) cell, germinal center, and T follicular regulatory (TFR) cell-independent. In contrast, IgG1 and IgE production to peanut required TFH cells. These data suggest an alternative paradigm in which the cellular mechanism of IgA production to food antigens is distinct from IgE and IgG1. We developed an equivalent assay to study this process in stool samples from healthy, nonallergic humans, which revealed substantial levels of peanut-specific IgA that were stable over time. Similar to mice, patients with loss of CD40L function had impaired titers of gut peanut-specific IgA. This work challenges two widely believed but untested paradigms about antibody production to dietary antigens: (i) the steady state/tolerogenic response to food antigens includes IgA production and (ii) TFH cells drive food-specific gut IgA.
|
|
50. |
- Zimmermannova, Olga, et al.
(author)
-
Restoring tumor immunogenicity with dendritic cell reprogramming
- 2023
-
In: Science Immunology. - 2470-9468. ; 8:85
-
Journal article (peer-reviewed)abstract
- Decreased antigen presentation contributes to the ability of cancer cells to evade the immune system. We used the minimal gene regulatory network of type 1 conventional dendritic cells (cDC1) to reprogram cancer cells into professional antigen-presenting cells (tumor-APCs). Enforced expression of the transcription factors PU.1, IRF8, and BATF3 (PIB) was sufficient to induce the cDC1 phenotype in 36 cell lines derived from human and mouse hematological and solid tumors. Within 9 days of reprogramming, tumor-APCs acquired transcriptional and epigenetic programs associated with cDC1 cells. Reprogramming restored the expression of antigen presentation complexes and costimulatory molecules on the surfaces of tumor cells, allowing the presentation of endogenous tumor antigens on MHC-I and facilitating targeted killing by CD8 + T cells. Functionally, tumor-APCs engulfed and processed proteins and dead cells, secreted inflammatory cytokines, and cross-presented antigens to naïve CD8 + T cells. Human primary tumor cells could also be reprogrammed to increase their capability to present antigen and to activate patient-specific tumor-infiltrating lymphocytes. In addition to acquiring improved antigen presentation, tumor-APCs had impaired tumorigenicity in vitro and in vivo. Injection of in vitro generated melanoma-derived tumor-APCs into subcutaneous melanoma tumors delayed tumor growth and increased survival in mice. Antitumor immunity elicited by tumor-APCs was synergistic with immune checkpoint inhibitors. Our approach serves as a platform for the development of immunotherapies that endow cancer cells with the capability to process and present endogenous tumor antigens.
|
|