Expression of the Ladybird-like homeobox 2 transcription factor in the developing mouse testis and epididymis

<p>Abstract</p> <p>Background</p> <p>Homeoproteins are a class of transcription factors that are well-known regulators of organogenesis and cell differentiation in numerous tissues, including the male reproductive system. Indeed, a handful of homeoproteins have so far been identified in the testis and epididymis where a few were shown to play important developmental roles. Through a degenerate PCR approach aimed at identifying novel homeoproteins expressed in the male reproductive system, we have detected several homeoproteins most of which had never been described before in this tissue. One of these homeoproteins is Ladybird-like homeobox 2 (Lbx2), a homeobox factor mostly known to be expressed in the nervous system.</p> <p>Results</p> <p>To better define the expression profile of Lbx2 in the male reproductive system, we have performed <it>in situ </it>hybridization throughout testicular and epididymal development and into adulthood. Lbx2 expression was also confirmed by real time RT-PCR in those tissues and in several testicular and epididymal cell lines. In the epididymis, a highly segmented tissue, Lbx2 shows a regionalized expression profile, being more expressed in proximal segments of the caput epididymis than any other segment. In the testis, we found that Lbx2 is constitutively expressed at high levels in Sertoli cells. In interstitial cells, Lbx2 is weakly expressed during fetal and early postnatal life, highly expressed around P32-P36, and absent in adult animals. Finally, Lbx2 can also be detected in a population of germ cells in adults.</p> <p>Conclusion</p> <p>Altogether, our data suggest that the homeoprotein Lbx2 might be involved in the regulation of male reproductive system development and cell differentiation as well as in male epididymal segmentation.</p

Ets-1 is a negative regulator of Th17 differentiation

IL-17 is a proinflammatory cytokine that plays a role in the clearance of extracellular bacteria and contributes to the pathology of many autoimmune and allergic conditions. IL-17 is produced mainly by a newly characterized subset of T helper (Th) cells termed Th17. Although the role of Th17 cells in the pathology of autoimmune diseases is well established, the transcription factors regulating the differentiation of Th17 cells remain poorly characterized. We report that Ets-1–deficient Th cells differentiated more efficiently to Th17 cells than wild-type cells. This was attributed to both low IL-2 production and increased resistance to the inhibitory effect of IL-2 on Th17 differentiation. The resistance to IL-2 suppression was caused by a defect downstream of STAT5 phosphorylation, but was not caused by a difference in the level of RORγt. Furthermore, Ets-1–deficient mice contained an abnormally high level of IL-17 transcripts in their lungs and exhibited increased mucus production by airway epithelial cells in an IL-17–dependent manner. Based on these observations, we report that Ets-1 is a negative regulator of Th17 differentiation

326 The anti-TIGIT antibody M6223 induces significant anti-tumor efficacy and immune response via multiple mechanisms of action

BackgroundM6223 is a fully human antagonistic anti-T cell immunoreceptor with immunoglobulin and ITIM domains (TIGIT) antibody in IgG1 format with Fc-mediated effector function.MethodsThe ability of M6223 to block the interaction of TIGIT with its ligands, CD155 and CD112, and the interaction of TIGIT with CD226 was determined by a flow cytometry-based binding assay. The anti-tumor efficacy, immune profile, and effector function of M6223 were investigated in syngeneic tumor models in huTIGIT knock-in mice. M6223 was either formatted with an effector competent mouse IgG2c constant region (M6223-muIgG2c) or formatted with effector null mouse IgG1-D256A constant region (M6223-muIgG1) as two versions of chimeric antibodies for the in vivo studies.ResultsM6223 dose-dependently blocked the binding of TIGIT to its ligands, including CD155 and CD112, thereby inhibiting a TIGIT-mediated immunosuppressive pathway. In addition, M6223 interrupted the interaction of TIGIT with the costimulatory receptor CD226. By blocking the interactions, the chimeric protein M6223-muIgG2c showed anti-tumor efficacy in multiple tumor models, including an MC38 tumor model (figure 1), and generated tumor antigen-specific long-term protective immunity in immunocompetent huTIGIT knock-in mice. M6223 monotherapy dose-dependently elevated the ratio of CD8+ cytotoxic T cells to regulatory T cells and the ratio of CD226 to TIGIT expression in immune cells in the tumor microenvironment. We also found that M6223 selectively depleted suppressive and exhausted TIGIT+ immune cell subsets and the anti-tumor activity of effector null M6223-muIgG1 was significantly lost (p<0.0001), suggesting that Fc-mediated effector function contributes to M6223 anti-tumor activity. Antibody depletion studies demonstrated that CD8+ T cells and natural killer cells contributed to the anti-tumor activity of M6223 in a complementary manner.Abstract 326 Figure 1M6223-muIgG2c displayed dose-dependent anti-tumor efficacy. M6223-muIgG2c displayed dose-dependent anti-tumor efficacy in an MC38 tumor model in hTIGIT knock-in mice.ConclusionsGiven that TIGIT blockade can inhibit an immunosuppressive pathway as well as remove the suppression on a costimulatory pathway, M6223 has the potential to induce an anti-tumor immune response by three complementary mechanisms: direct blockade of the TIGIT pathway, stimulation of CD226 dimerization/activation, and depletion of TIGIT+ immune subsets by Fc-mediated effector function. Our data demonstrate that these complementary mechanisms orchestrate the anti-tumor activity of M6223. A Phase I, first-in-human clinical trial (NCT04457778) is underway to determine the safety, tolerability, maximum tolerated dose and recommended dose for expansion of M6223 as a single agent (Part 1A) and in combination with bintrafusp alfa (Part 1B) in patients with metastatic or locally advanced solid unresectable tumors.Ethics ApprovalAll animal experiments were performed in accordance with EMD Serono Research & Development Institute, Inc., Billerica, MA, USA, an affiliate of Merck KGaA (protocol 17-008, 20-005) and Wuxi AppTec Animal Care and Use Committee (IACUC) guidelines

Análisis de ADN Mitocondrial en restos de hijo putativo de Luis XVI, Rey de Francia y María Antonieta

Carl Wilhelm Naundorff fue sepultado en 1845 en Delft como Luis Charles, Duque de Normandía, “Luis XVII”. Sin embargo, el hijo de Luis XVI y María Antonieta-Luis XVII- falleció oficialmente en el templo de París en 1795. Con el fin de determinar la identidad de Naundorff, se comparó las secuencias de las ondas del ADNmitocondrial (ADNmt) de sus restos con las secuencias obtenidas a partir del cabello de dos hermanas de María Antonieta, de la misma María Antonieta, y con las secuencias obtenidas de las muestras del ADN de dos parientes maternos vivos. La secuencia del ADNmt de una muestra de hueso de Naundorff mostró dos diferencias en los nucleótidos en cuanto a la secuencia del de las tres hermanas y cuatro diferencias en las secuencias de los parientes maternos vivos basado en esta evidencia resulta muy remoto que Naundorff sea el hijo de María Antonieta

Reply to: Ultrafast evolution and transient phases of a prototype out-of-equilibrium Mott-Hubbard material

International audienceReplying to D. Moreno-Mencía et al. Nature Communicationshttps://doi.org/10.1038/s41467-019-11743-3 (2019)

Mutation analysis and characterization of ATR sequence variants in breast cancer cases from high-risk French Canadian breast/ovarian cancer families

BACKGROUND: Ataxia telangiectasia-mutated and Rad3-related (ATR) is a member of the PIK-related family which plays, along with ATM, a central role in cell-cycle regulation. ATR has been shown to phosphorylate several tumor suppressors like BRCA1, CHEK1 and TP53. ATR appears as a good candidate breast cancer susceptibility gene and the current study was designed to screen for ATR germline mutations potentially involved in breast cancer predisposition. METHODS: ATR direct sequencing was performed using a fluorescent method while widely available programs were used for linkage disequilibrium (LD), haplotype analyses, and tagging SNP (tSNP) identification. Expression analyses were carried out using real-time PCR. RESULTS: The complete sequence of all exons and flanking intronic sequences were analyzed in DNA samples from 54 individuals affected with breast cancer from non-BRCA1/2 high-risk French Canadian breast/ovarian families. Although no germline mutation has been identified in the coding region, we identified 41 sequence variants, including 16 coding variants, 3 of which are not reported in public databases. SNP haplotypes were established and tSNPs were identified in 73 healthy unrelated French Canadians, providing a valuable tool for further association studies involving the ATR gene, using large cohorts. Our analyses led to the identification of two novel alternative splice transcripts. In contrast to the transcript generated by an alternative splicing site in the intron 41, the one resulting from a deletion of 121 nucleotides in exon 33 is widely expressed, at significant but relatively low levels, in both normal and tumoral cells including normal breast and ovarian tissue. CONCLUSION: Although no deleterious mutations were identified in the ATR gene, the current study provides an haplotype analysis of the ATR gene polymorphisms, which allowed the identification of a set of SNPs that could be used as tSNPs for large-scale association studies. In addition, our study led to the characterization of a novel Δ33 splice form, which could generate a putative truncated protein lacking several functional domains. Additional studies in large cohorts and other populations will be needed to further evaluate if common and/or rare ATR sequence variants can be associated with a modest or intermediate breast cancer risk

Immunomodulation with toll-like receptor 7 ligands in infections and allergic diseases

Modulation of the immune response to treat various infectious and allergic diseases as well as certain forms of cancer has been employed since William B. Coley injected a mixture of bacteria into patients with large inoperable tumors over 100 years ago. The imidazoquinoline compounds are nucleoside analogs with strong type I interferon inducing activity. Recently, these compounds have been found to mediate their effects through a subset of the Toll-like receptor (TLR) family. A topical cream containing imiquimod, a member of the imidazoquinoline family, is currently employed in humans for the treatment of genital warts caused by the human papilloma virus, against actinic keratosis as well as for topical treatment of primary superficial basal cell carcinoma. The goal of the present study was to determine the potential of imidazoquinolines in the treatment of other infectious and allergic diseases as well as their mechanism of action. Furthermore, the role of possible modulators of response to these chemicals has been studied. We show that imidazoquinoline treatment can increase mycobactericidal activity in mice carrying a resistant (wild type) allele of SLC11A1 (formerly natural resistance associated macrophage protein 1 (NRAMP1)). NRAMP1 affected responsiveness to imidazoquinolines in macrophages by modulating P38 MAPK activation as well as atypical PKC activity both of which are required for optimal immunodulatory activity by these TLR ligands. Imidazoquinoline treatment also prevented development of atopic allergic asthma in mice sensitized and challenged with ovalbumin by preventing inflammatory cytokine production as well as eosinophil infiltration in the lungs. Interestingly, this drug when used as a therapeutic agent against allergic asthma was equally efficient in mice carrying the wild type (resistant) or the susceptible allele of the Nramp1 gene. This suggests that NRAMP1 modulates response to imidazoquinoline treatment in models dependent on macrophage subsets which require NRAMP1 function to become activated to an appropriate degree. Taken together, the presented study broadens the possible applicability of imidazoquinolines to the treatment of mycobacterial infections as well as to allergic asthma treatment and defines an important role for NRAMP1 in regulating responses to this family of pharmaceutical compounds

La place du lecteur dans le texte balzacien

Quelle place le texte balzacien attribue-t-il à son lecteur ? En nous plaçant au croisement des théories de la lecture de Wolfgang Iser et d'Umberto Eco, des approches de la pragmatique, et des recherches sur la poétique balzacienne, nous analysons les mécanismes que Balzac met en place pour " construire " son lecteur et susciter l'adhésion au texte romanesque, et nous tentons ainsi de déterminer le rôle conféré au lecteur et la liberté dont il dispose au sein de La Comédie humaine. Nous étudions tout d'abord la place du lecteur dans les textes romanesques et préfaciels, en privilégiant des approches poétiques, narratologiques et pragmatiques. Un mouvement progressif nous conduit de l'interprétation des procédés de " mise sous tutelle " du lecteur au dévoilement des multiples dispositifs qui l'instituent en foyer d'interprétation indispensable au fonctionnement de la fiction. Nous examinons par ailleurs les pactes de lecture établis dans les préfaces balzaciennes, ainsi que l'évolution des stratégies employées par l'auteur pour y établir un contact avec son public. Quittant le cœur des textes pour entrer dans la construction architecturale de La Comédie humaine, nous analysons ensuite, du point de vue de l'esthétique de la réception, la difficile saisie par les lecteurs du XIXe siècle de la déconcertante " macro-œuvre " balzacienne, ainsi que les effets de lecture qui découlent de ses différentes structurations possibles. Nous interrogeons enfin le dynamisme et le mouvement consubstantiels à l'architecture de La Comédie humaine, en étudiant la navigation des livres et du lecteur au sein du système. Nous examinons, dans une perspective génétique, les déplacements de certains romans dans le classement, et, par des approches poétiques et narratologiques, les différents modes de parcours ouverts au lecteur pour traverser La Comédie humaineST DENIS-BU PARIS8 (930662101) / SudocSudocFranceF

Dynamic Expression of the Homeobox Factor PBX1 during Mouse Testis Development

Members of the pre-B-cell leukemia transcription factor (PBX) family of homeoproteins are mainly known for their involvement in hematopoietic cell differentiation and in the development of leukemia. The four PBX proteins, PBX1, PBX2, PBX3 and PBX4, belong to the three amino acid loop extension (TALE) superfamily of homeoproteins which are important transcriptional cofactors in several developmental processes involving homeobox (HOX) factors. Mutations in the human PBX1 gene are responsible for cases of gonadal dysgenesis with absence of male sex differentiation while Pbx1 inactivation in the mouse causes a failure in Leydig cell differentiation and function. However, no data is available regarding the expression profile of this transcription factor in the testis. To fill this knowledge gap, we have characterized PBX1 expression during mouse testicular development. Real time PCRs and Western blots confirmed the presence Pbx1 mRNA and PBX1 protein in different Leydig and Sertoli cell lines. The cellular localization of the PBX1 protein was determined by immunohistochemistry and immunofluorescence on mouse testis sections at different embryonic and postnatal developmental stages. PBX1 was detected in interstitial cells and in peritubular myoid cells from embryonic life until puberty. Most interstitial cells expressing PBX1 do not express the Leydig cell marker CYP17A1, indicating that they are not differentiated and steroidogenically active Leydig cells. In adults, PBX1 was mainly detected in Sertoli cells. The presence of PBX1 in different somatic cell populations during testicular development further supports a direct role for this transcription factor in testis cell differentiation and in male reproductive function