Life Sciences Research for Lifelong Health

Publications

The Babraham Institute Publications database contains details of all publications resulting from our research groups and scientific services.

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Title / Authors / Details Open Access Download

Epigenetic control of CD8+ T cell differentiation.
Henning AN, Roychoudhuri R, Restifo NP

Upon stimulation, small numbers of naive CD8+ T cells proliferate and differentiate into a variety of memory and effector cell types. CD8+ T cells can persist for years and kill tumour cells and virally infected cells. The functional and phenotypic changes that occur during CD8+ T cell differentiation are well characterized, but the epigenetic states that underlie these changes are incompletely understood. Here, we review the epigenetic processes that direct CD8+ T cell differentiation and function. We focus on epigenetic modification of DNA and associated histones at genes and their regulatory elements. We also describe structural changes in chromatin organization that affect gene expression. Finally, we examine the translational potential of epigenetic interventions to improve CD8+ T cell function in individuals with chronic infections and cancer.

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Nature reviews. Immunology, , 1474-1741, , 2018

PMID: 29379213

The RNA-binding protein PTBP1 is necessary for B cell selection in germinal centers.
Monzón-Casanova E, Screen M, Díaz-Muñoz MD, Coulson RMR, Bell SE, Lamers G, Solimena M, Smith CWJ, Turner M

Antibody affinity maturation occurs in germinal centers (GCs), where B cells cycle between the light zone (LZ) and the dark zone. In the LZ, GC B cells bearing immunoglobulins with the highest affinity for antigen receive positive selection signals from helper T cells, which promotes their rapid proliferation. Here we found that the RNA-binding protein PTBP1 was needed for the progression of GC B cells through late S phase of the cell cycle and for affinity maturation. PTBP1 was required for proper expression of the c-MYC-dependent gene program induced in GC B cells receiving T cell help and directly regulated the alternative splicing and abundance of transcripts that are increased during positive selection to promote proliferation.

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Nature immunology, , 1529-2916, , 2018

PMID: 29358707

PI3K induces B-cell development and regulates B cell identity.
Abdelrasoul H, Werner M, Setz CS, Okkenhaug K, Jumaa H

Phosphoinositide-3 kinase (PI3K) signaling is important for the survival of numerous cell types and class IA of PI3K is specifically required for the development of B cells but not for T cell development. Here, we show that class IA PI3K-mediated signals induce the expression of the transcription factor Pax5, which plays a central role in B cell commitment and differentiation by activating the expression of central B cell-specific signaling proteins such as SLP-65 and CD19. Defective class IA PI3K function leads to reduction in Pax5 expression and prevents B cell development beyond the stage expressing the precursor B cell receptor (pre-BCR). Investigating the mechanism of PI3K-induced Pax5 expression revealed that it involves a network of transcription factors including FoxO1 and Irf4 that directly binds to the Pax5 gene. Together, our results suggest that PI3K signaling links survival and differentiation of developing B cells with B cell identity and that decreased PI3K activity in pre-B cells results in reduced Pax5 expression and lineage plasticity.

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Scientific reports, 8, 2045-2322, 1327, 2018

PMID: 29358580

Open Access

RNA-binding proteins control gene expression and cell fate in the immune system.
Turner M, Díaz-Muñoz MD

RNA-binding proteins (RBPs) are essential for the development and function of the immune system. They interact dynamically with RNA to control its biogenesis and turnover by transcription-dependent and transcription-independent mechanisms. In this Review, we discuss the molecular mechanisms by which RBPs allow gene expression changes to occur at different speeds and to varying degrees, and which RBPs regulate the diversity of the transcriptome and proteome. These proteins are nodes for integration of transcriptional and signaling networks and are intimately linked to intermediary metabolism. They are essential components of regulatory feedback mechanisms that maintain immune tolerance and limit inflammation. The role of RBPs in malignancy and autoimmunity has led to their emergence as targets for the development of new therapeutic modalities.

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Nature immunology, , 1529-2916, , 2018

PMID: 29348497

Regulatory T Cell Migration Is Dependent on Glucokinase-Mediated Glycolysis.
Kishore M, Cheung KCP, Fu H, Bonacina F, Wang G, Coe D, Ward EJ, Colamatteo A, Jangani M, Baragetti A, Matarese G, Smith DM, Haas R, Mauro C, Wraith DC, Okkenhaug K, Catapano AL, De Rosa V, Norata GD, Marelli-Berg FM

Migration of activated regulatory T (Treg) cells to inflamed tissue is crucial for their immune-modulatory function. While metabolic reprogramming during Treg cell differentiation has been extensively studied, the bioenergetics of Treg cell trafficking remains undefined. We have investigated the metabolic demands of migrating Treg cells in vitro and in vivo. We show that glycolysis was instrumental for their migration and was initiated by pro-migratory stimuli via a PI3K-mTORC2-mediated pathway culminating in induction of the enzyme glucokinase (GCK). Subsequently, GCK promoted cytoskeletal rearrangements by associating with actin. Treg cells lacking this pathway were functionally suppressive but failed to migrate to skin allografts and inhibit rejection. Similarly, human carriers of a loss-of-function GCK regulatory protein gene-leading to increased GCK activity-had reduced numbers of circulating Treg cells. These cells displayed enhanced migratory activity but similar suppressive function, while conventional T cells were unaffected. Thus, GCK-dependent glycolysis regulates Treg cell migration.

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Immunity, 47, 1097-4180, 875-889.e10, 2017

PMID: 29166588

Open Access

TFR cells trump autoimmune antibody responses to limit sedition.
Linterman MA, Toellner KM

Nature immunology, 18, 1529-2916, 1185-1186, 2017

PMID: 29044242

Tia1 dependent regulation of mRNA subcellular location and translation controls p53 expression in B cells.
Díaz-Muñoz MD, Kiselev VY, Novère NL, Curk T, Ule J, Turner M

Post-transcriptional regulation of cellular mRNA is essential for protein synthesis. Here we describe the importance of mRNA translational repression and mRNA subcellular location for protein expression during B lymphocyte activation and the DNA damage response. Cytoplasmic RNA granules are formed upon cell activation with mitogens, including stress granules that contain the RNA binding protein Tia1. Tia1 binds to a subset of transcripts involved in cell stress, including p53 mRNA, and controls translational silencing and RNA granule localization. DNA damage promotes mRNA relocation and translation in part due to dissociation of Tia1 from its mRNA targets. Upon DNA damage, p53 mRNA is released from stress granules and associates with polyribosomes to increase protein synthesis in a CAP-independent manner. Global analysis of cellular mRNA abundance and translation indicates that this is an extended ATM-dependent mechanism to increase protein expression of key modulators of the DNA damage response.Sequestering mRNA in cytoplasmic stress granules is a mechanism for translational repression. Here the authors find that p53 mRNA, present in stress granules in activated B lymphocytes, is released upon DNA damage and is translated in a CAP-independent manner.

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Nature communications, 8, 2041-1723, 530, 2017

PMID: 28904350

Open Access

RNA-binding protein ZFP36L1 maintains posttranscriptional regulation of bile acid metabolism.
Tarling EJ, Clifford BL, Cheng J, Morand P, Cheng A, Lester E, Sallam T, Turner M, de Aguiar Vallim TQ

Bile acids function not only as detergents that facilitate lipid absorption but also as signaling molecules that activate the nuclear receptor farnesoid X receptor (FXR). FXR agonists are currently being evaluated as therapeutic agents for a number of hepatic diseases due to their lipid-lowering and antiinflammatory properties. FXR is also essential for maintaining bile acid homeostasis and prevents the accumulation of bile acids. Elevated bile acids activate FXR, which in turn switches off bile acid synthesis by reducing the mRNA levels of bile acid synthesis genes, including cholesterol 7α-hydroxylase (Cyp7a1). Here, we show that FXR activation triggers a rapid posttranscriptional mechanism to degrade Cyp7a1 mRNA. We identified the RNA-binding protein Zfp36l1 as an FXR target gene and determined that gain and loss of function of ZFP36L1 reciprocally regulate Cyp7a1 mRNA and bile acid levels in vivo. Moreover, we found that mice lacking hepatic ZFP36L1 were protected from diet-induced obesity and steatosis. The reduced adiposity and antisteatotic effects observed in ZFP36L1-deficient mice were accompanied by impaired lipid absorption that was consistent with altered bile acid metabolism. Thus, the ZFP36L1-dependent regulation of bile acid metabolism is an important metabolic contributor to obesity and hepatosteatosis.

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The Journal of clinical investigation, , 1558-8238, , 2017

PMID: 28891815

Open Access

Chromosome contacts in activated T cells identify autoimmune disease candidate genes.
Burren OS, Rubio García A, Javierre BM, Rainbow DB, Cairns J, Cooper NJ, Lambourne JJ, Schofield E, Castro Dopico X, Ferreira RC, Coulson R, Burden F, Rowlston SP, Downes K, Wingett SW, Frontini M, Ouwehand WH, Fraser P, Spivakov M, Todd JA, Wicker LS, Cutler AJ, Wallace C

Autoimmune disease-associated variants are preferentially found in regulatory regions in immune cells, particularly CD4(+) T cells. Linking such regulatory regions to gene promoters in disease-relevant cell contexts facilitates identification of candidate disease genes.

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Genome biology, 18, 1474-760X, 165, 2017

PMID: 28870212

Open Access

Human blood Tfr cells are indicators of ongoing humoral activity not fully licensed with suppressive function.
Fonseca VR, Agua-Doce A, Maceiras AR, Pierson W, Ribeiro F, Romão VC, Pires AR, da Silva SL, Fonseca JE, Sousa AE, Linterman MA, Graca L

Germinal center (GC) responses are controlled by T follicular helper (Tfh) and T follicular regulatory (Tfr) cells and are crucial for the generation of high-affinity antibodies. Although the biology of human circulating and tissue Tfh cells has been established, the relationship between blood and tissue Tfr cells defined as CXCR5(+)Foxp3(+) T cells remains elusive. We found that blood Tfr cells are increased in Sjögren syndrome, an autoimmune disease with ongoing GC reactions, especially in patients with high autoantibody titers, as well as in healthy individuals upon influenza vaccination. Although blood Tfr cells correlated with humoral responses, they lack full B cell-suppressive capacity, despite being able to suppress T cell proliferation. Blood Tfr cells have a naïve-like phenotype, although they are absent from human thymus or cord blood. We found that these cells were generated in peripheral lymphoid tissues before T-B interaction, as they are maintained in B cell-deficient patients. Therefore, blood CXCR5(+)Foxp3(+) T cells in human pathology indicate ongoing humoral activity but are not fully competent circulating Tfr cells.

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Science immunology, 2, 2470-9468, , 2017

PMID: 28802258

Cellular Stress in the Context of an Inflammatory Environment Supports TGF-β-Independent T Helper-17 Differentiation.
Brucklacher-Waldert V, Ferreira C, Stebegg M, Fesneau O, Innocentin S, Marie JC, Veldhoen M

T helper-17 (Th17) cells are associated with inflammatory disorders and cancer. We report that environmental conditions resulting in cellular stress, such as low oxygen, glucose, and isotonic stress, particularly enhance the generation of Th17 cells. Pharmacological inhibition of cell stress reduces Th17 cell differentiation while stress inducers enhance the development of Th17 cells. The cellular stress response results in Th17 cell development via sustained cytoplasmic calcium levels and, in part, XBP1 activity. Furthermore, in an inflammatory environment, conditions resulting in cell stress can bring about de novo Th17 cell differentiation, even in the absence of transforming growth factor β (TGF-β) signaling. In vivo, cell stress inhibition enhances resistance to Th17-mediated autoimmunity while stress-exposed T cells enhance disease severity. Adverse metabolic environments during inflammation provide a link between adaptive immunity and inflammation and may represent a risk factor for the development of chronic inflammatory conditions by facilitating Th17 cell differentiation.

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Cell reports, 19, 2211-1247, 2357-2370, 2017

PMID: 28614720

Characterization of the B Cell Transcriptome Bound by RNA-Binding Proteins with iCLIP.
Díaz-Muñoz MD, Monzón-Casanova E, Turner M

Posttranscriptional regulation of gene expression shapes the B cell transcriptome and controls messenger RNA (mRNA) translation into protein. Recent reports have highlighted the importance of RNA binding proteins (RBPs) for mRNA splicing, subcellular location, stability, and translation during B lymphocyte development, activation, and differentiation. Here we describe individual-nucleotide resolution UV cross-linking and immunoprecipitation (iCLIP) in primary lymphocytes, a method that maps RNA-protein interactions in a genome-wide scale allowing mechanistic analysis of RBP function. We discuss the latest improvements in iCLIP technology and provide some examples of how integration of the RNA-protein interactome with other high-throughput mRNA sequencing methodologies uncovers the important role of RBP-mediated RNA regulation in key biological cell processes.

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Methods in molecular biology (Clifton, N.J.), 1623, 1940-6029, 159-179, 2017

PMID: 28589356

Identifying Follicular Regulatory T Cells by Confocal Microscopy.
Vanderleyden I, Linterman MA

Follicular regulatory T cells are a subset of Foxp3(+) regulatory T cells that migrate into the B cell follicle after infection or immunization and modulate the germinal center response. The anatomical positioning of follicular regulatory T cells within the germinal center is a defining characteristic of this subset of regulatory T cells; because of this, it is critical that studies of follicular regulatory T cells are able to identify them in situ. In this chapter we describe an immunofluorescence staining method to visualize follicular regulatory T cells in frozen secondary lymphoid tissue sections by confocal imaging.

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Methods in molecular biology (Clifton, N.J.), 1623, 1940-6029, 87-93, 2017

PMID: 28589349

No Functional Role for microRNA-342 in a Mouse Model of Pancreatic Acinar Carcinoma.
Dooley J, Lagou V, Pasciuto E, Linterman MA, Prosser HM, Himmelreich U, Liston A

The intronic microRNA (miR)-342 has been proposed as a potent tumor-suppressor gene. miR-342 is found to be downregulated or epigenetically silenced in multiple different tumor sites, and this loss of expression permits the upregulation of several key oncogenic pathways. In several different cell lines, lower miR-342 expression results in enhanced proliferation and metastasis potential, both in vitro and in xenogenic transplant conditions. Here, we sought to determine the function of miR-342 in an in vivo spontaneous cancer model, using the Ela1-TAg transgenic model of pancreatic acinar carcinoma. Through longitudinal magnetic resonance imaging monitoring of Ela1-TAg transgenic mice, either wild-type or knockout for miR-342, we found no role for miR-342 in the development, growth rate, or pathogenicity of pancreatic acinar carcinoma. These results indicate the importance of assessing miR function in the complex physiology of in vivo model systems and indicate that further functional testing of miR-342 is required before concluding it is a bona fide tumor-suppressor-miR.

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Frontiers in oncology, 7, , 101, 2017

PMID: 28573106

Open Access

Escherichia coli Heat-Labile Enterotoxin B Limits T Cells Activation by Promoting Immature Dendritic Cells and Enhancing Regulatory T Cell Function.
Bignon A, Watt AP, Linterman MA

Treatments to limit T cell activation are essential for managing autoimmune and inflammatory disorders. The B subunit of Escherichia coli heat-labile enterotoxin (EtxB) is known to ameliorate inflammatory disease in vivo but the mechanism by which this is mediated is not well understood. Here, we show that following intranasal administration, EtxB acts on two key cellular regulators of T cell activation: regulatory T cells and dendritic cells (DCs). EtxB enhances the proliferation of lung regulatory T cells and doubles their suppressive function, likely through an increase in expression of the Treg effector molecule CTLA-4. EtxB supports the generation of interleukin-10-producing DCs that are unable to activate T cells. These data show, for the first time, that mucosal EtxB treatment limits T cells activation by acting jointly on two distinct types of immune cells.

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Frontiers in immunology, 8, , 560, 2017

PMID: 28555139

Open Access

BACH2 immunodeficiency illustrates an association between super-enhancers and haploinsufficiency.
Afzali B, Grönholm J, Vandrovcova J, O'Brien C, Sun HW, Vanderleyden I, Davis FP, Khoder A, Zhang Y, Hegazy AN, Villarino AV, Palmer IW, Kaufman J, Watts NR, Kazemian M, Kamenyeva O, Keith J, Sayed A, Kasperaviciute D, Mueller M, Hughes JD, Fuss IJ, Sadiyah MF, Montgomery-Recht K, McElwee J, Restifo NP, Strober W, Linterman MA, Wingfield PT, Uhlig HH, Roychoudhuri R, Aitman TJ, Kelleher P, Lenardo MJ, O'Shea JJ, Cooper N, Laurence ADJ

The transcriptional programs that guide lymphocyte differentiation depend on the precise expression and timing of transcription factors (TFs). The TF BACH2 is essential for T and B lymphocytes and is associated with an archetypal super-enhancer (SE). Single-nucleotide variants in the BACH2 locus are associated with several autoimmune diseases, but BACH2 mutations that cause Mendelian monogenic primary immunodeficiency have not previously been identified. Here we describe a syndrome of BACH2-related immunodeficiency and autoimmunity (BRIDA) that results from BACH2 haploinsufficiency. Affected subjects had lymphocyte-maturation defects that caused immunoglobulin deficiency and intestinal inflammation. The mutations disrupted protein stability by interfering with homodimerization or by causing aggregation. We observed analogous lymphocyte defects in Bach2-heterozygous mice. More generally, we observed that genes that cause monogenic haploinsufficient diseases were substantially enriched for TFs and SE architecture. These findings reveal a previously unrecognized feature of SE architecture in Mendelian diseases of immunity: heterozygous mutations in SE-regulated genes identified by whole-exome/genome sequencing may have greater significance than previously recognized.

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Nature immunology, , 1529-2916, , 2017

PMID: 28530713

BACH transcription factors in innate and adaptive immunity.
Igarashi K, Kurosaki T, Roychoudhuri R

BTB and CNC homology (BACH) proteins are transcriptional repressors of the basic region leucine zipper (bZIP) transcription factor family. Recent studies indicate widespread roles of BACH proteins in controlling the development and function of the innate and adaptive immune systems, including the differentiation of effector and memory cells of the B and T cell lineages, CD4(+) regulatory T cells and macrophages. Here, we emphasize similarities at a molecular level in the cell-type-specific activities of BACH factors, proposing that competitive interactions of BACH proteins with transcriptional activators of the bZIP family form a common mechanistic theme underlying their diverse actions. The findings contribute to a general understanding of how transcriptional repressors shape lineage commitment and cell-type-specific functions through repression of alternative lineage programmes.

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Nature reviews. Immunology, , 1474-1741, , 2017

PMID: 28461702

Multi-tissue DNA methylation age predictor in mouse.
Stubbs TM, Bonder MJ, Stark AK, Krueger F, Bolland D, Butcher G, Chandra T, Clark SJ, Corcoran A, Eckersley-Maslin M, Field L, Frising UC, Gilbert C, Guedes J, Hernando-Herraez I, Houseley J, Kemp F, MacQueen A, Okkenhaug K, Rhoades M, Santbergen MJC, Stebegg M, von Meyenn F, Stegle O, Reik W

DNA methylation changes at a discrete set of sites in the human genome are predictive of chronological and biological age. However, it is not known whether these changes are causative or a consequence of an underlying ageing process. It has also not been shown whether this epigenetic clock is unique to humans or conserved in the more experimentally tractable mouse.

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Genome biology, 18, 1474-760X, 68, 2017

PMID: 28399939

Open Access

Maintenance of the marginal-zone B cell compartment specifically requires the RNA-binding protein ZFP36L1.
Newman R, Ahlfors H, Saveliev A, Galloway A, Hodson DJ, Williams R, Besra GS, Cunningham AF, Bell SE, Turner M

RNA-binding proteins of the ZFP36 family are best known for inhibiting the expression of cytokines through binding to AU-rich elements in the 3' untranslated region and promoting mRNA decay. Here we identified an indispensable role for ZFP36L1 as the regulator of a post-transcriptional hub that determined the identity of marginal-zone B cells by promoting their proper localization and survival. ZFP36L1 controlled a gene-expression program related to signaling, cell adhesion and locomotion; it achieved this in part by limiting expression of the transcription factors KLF2 and IRF8, which are known to enforce the follicular B cell phenotype. These mechanisms emphasize the importance of integrating transcriptional and post-transcriptional processes by RNA-binding proteins for maintaining cellular identity among closely related cell types.

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Nature immunology, , 1529-2916, , 2017

PMID: 28394372

Stromal networking: cellular connections in the germinal centre.
Denton AE, Linterman MA

Secondary lymphoid organs are organized into distinct zones, governed by different types of mesenchymal stromal cells. These stromal cell subsets are critical for the generation of protective humoral immunity because they direct the migration of, and interaction between, multiple immune cell types to form the germinal centre. The germinal centre response generates long-lived antibody-secreting plasma cells and memory B cells which can provide long-term protection against re-infection. Stromal cell subsets mediate this response through control of immune cell trafficking, activation, localization and antigen access within the secondary lymphoid organ. Further, distinct populations of stromal cells underpin the delicate spatial organization of immune cells within the germinal centre. Because of this, the interactions between immune cells and stromal cells in secondary lymphoid organs are fundamental to the germinal centre response. Herein we review how this unique relationship leads to effective germinal centre responses.

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Current opinion in immunology, 45, 1879-0372, 103-111, 2017

PMID: 28319729

Cell cycle RNA regulons coordinating early lymphocyte development.
Galloway A, Turner M

Lymphocytes undergo dynamic changes in gene expression as they develop from progenitor cells lacking antigen receptors, to mature cells that are prepared to mount immune responses. While transcription factors have established roles in lymphocyte development, they act in concert with post-transcriptional and post-translational regulators to determine the proteome. Furthermore, the post-transcriptional regulation of RNA regulons consisting of mRNAs whose protein products act cooperatively allows RNA binding proteins to exert their effects at multiple points in a pathway. Here, we review recent evidence demonstrating the importance of RNA binding proteins that control the cell cycle in lymphocyte development and discuss the implications for tumorigenesis. For further resources related to this article, please visit the WIREs website.

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Wiley interdisciplinary reviews. RNA, , 1757-7012, , 2017

PMID: 28231639

Obesity-Induced Metabolic Stress Leads to Biased Effector Memory CD4(+) T Cell Differentiation via PI3K p110δ-Akt-Mediated Signals.
Mauro C, Smith J, Cucchi D, Coe D, Fu H, Bonacina F, Baragetti A, Cermenati G, Caruso D, Mitro N, Catapano AL, Ammirati E, Longhi MP, Okkenhaug K, Norata GD, Marelli-Berg FM

Low-grade systemic inflammation associated to obesity leads to cardiovascular complications, caused partly by infiltration of adipose and vascular tissue by effector T cells. The signals leading to T cell differentiation and tissue infiltration during obesity are poorly understood. We tested whether saturated fatty acid-induced metabolic stress affects differentiation and trafficking patterns of CD4(+) T cells. Memory CD4(+) T cells primed in high-fat diet-fed donors preferentially migrated to non-lymphoid, inflammatory sites, independent of the metabolic status of the hosts. This was due to biased CD4(+) T cell differentiation into CD44(hi)-CCR7(lo)-CD62L(lo)-CXCR3(+)-LFA1(+) effector memory-like T cells upon priming in high-fat diet-fed animals. Similar phenotype was observed in obese subjects in a cohort of free-living people. This developmental bias was independent of any crosstalk between CD4(+) T cells and dendritic cells and was mediated via direct exposure of CD4(+) T cells to palmitate, leading to increased activation of a PI3K p110δ-Akt-dependent pathway upon priming.

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Cell metabolism, , 1932-7420, , 2017

PMID: 28190771

Open Access

Defective germinal center B-cell response and reduced arthritic pathology in microRNA-29a-deficient mice.
van Nieuwenhuijze A, Dooley J, Humblet-Baron S, Sreenivasan J, Koenders M, Schlenner SM, Linterman M, Liston A

MicroRNA (miR) are short non-coding RNA sequences of 19-24 nucleotides that regulate gene expression by binding to mRNA target sequences. The miR-29 family of miR (miR-29a, b-1, b-2 and c) is a key player in T-cell differentiation and effector function, with deficiency causing thymic involution and a more inflammatory T-cell profile. However, the relative roles of different miR-29 family members in these processes have not been dissected. We studied the immunological role of the individual members of the miR-29 family using mice deficient for miR-29a/b-1 or miR-29b-2/c in homeostasis and during collagen-induced arthritis. We found a definitive hierarchy of immunological function, with the strong phenotype of miR-29a-deficiency in thymic involution and T-cell activation being reduced or absent in miR-29c-deficient mice. Strikingly, despite elevating the Th1 and Th17 responses, loss of miR-29a conferred near-complete protection from collagen-induced arthritis (CIA), with profound defects in B-cell proliferation and antibody production. Our results identify the hierarchical structure of the miR-29 family in T-cell biology, and identify miR-29a in B cells as a potential therapeutic target in arthritis.

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Cellular and molecular life sciences : CMLS, , 1420-9071, , 2017

PMID: 28124096

RNA-binding proteins mind the GAPs.
Turner M, Monzón-Casanova E

Nature immunology, 18, 1529-2916, 146-148, 2017

PMID: 28102216

Diet-Derived Short Chain Fatty Acids Stimulate Intestinal Epithelial Cells To Induce Mucosal Tolerogenic Dendritic Cells.
Goverse G, Molenaar R, Macia L, Tan J, Erkelens MN, Konijn T, Knippenberg M, Cook EC, Hanekamp D, Veldhoen M, Hartog A, Roeselers G, Mackay CR, Mebius RE

The gastrointestinal tract is continuously exposed to many environmental factors that influence intestinal epithelial cells and the underlying mucosal immune system. In this article, we demonstrate that dietary fiber and short chain fatty acids (SCFAs) induced the expression of the vitamin A-converting enzyme RALDH1 in intestinal epithelial cells in vivo and in vitro, respectively. Furthermore, our data showed that the expression levels of RALDH1 in small intestinal epithelial cells correlated with the activity of vitamin A-converting enzymes in mesenteric lymph node dendritic cells, along with increased numbers of intestinal regulatory T cells and a higher production of luminal IgA. Moreover, we show that the consumption of dietary fiber can alter the composition of SCFA-producing microbiota and SCFA production in the small intestines. In conclusion, our data illustrate that dietary adjustments affect small intestinal epithelial cells and can be used to modulate the mucosal immune system.

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Journal of immunology (Baltimore, Md. : 1950), , 1550-6606, , 2017

PMID: 28100682