Expression of B lymphocyte-induced maturation protein 1 (Blimp-1) in keratinocyte and cytokine signalling drives human Th17 response in psoriasis.

Transcriptional factor B lymphocyte-induced maturation protein 1 (Blimp-1) is pivotally implicated in T helper 17 (Th17) cell differentiation. This study investigated expression of the Blimp-1 protein, positive regulatory domain 1 (PRDM1), and cytokine genes in psoriasis (PsO). Affected (AS-PsO) and non-affected skin (nAS-PsO) samples were used to assess gene and protein expressions by reverse transcription-quantitative PCR (RT-qPCR), and immunostaining and confocal microscopy, respectively; the normalised public transcriptomic data permitted differential gene expression analyses. On RT-qPCR, PRDM1 and IL17A transcripts showed higher expression in AS-PsO than in nAS-PsO (n = 34) (p < 0.001; p < 0.0001, respectively). Confocal microscopy showed Blimp-1 protein expression in epidermal layer keratinocytes in AS-PsO, but not in nAS-PsO. Bioinformatic analysis of the transcriptomic dataset GSE13355 corroborated the increased PRDM1, signal transducer and activator of transcription 3 (STAT3), IL12B, TNF, IL17A, IL6, IL1B, IL22, and IL10 gene expression in AS-PsO, when compared to normal skin and nAS-PsO (p < 0.001). PRDM1 expression correlated positively (p < 0.0001) with that of IL17A (r = 0.7), IL1B (r = 0.67), IL12B (r = 0.6), IL6 (r = 0.59), IL22 (r = 0.53), IL23A (r = 0.47), IL21 (r = 0.47), IL27 (r = 0.34), IL23R (r = 0.32), S100 calcium binding protein A9 (r = 0.63), and lipocalin 2 (r = 0.50), and negatively with that of TGFB1 (r = - 0.28) and RORC (r = - 0.60). Blimp-1 may be critical in the pathogenesis of PsO dysregulation involving the Th17 inflammatory pathway. This knowledge may accelerate the development of new treatments.

Blimp-1 is essential for allergen-induced asthma and Th2 cell development in the lung.

A Th2 immune response is central to allergic airway inflammation, which afflicts millions worldwide. However, the mechanisms that augment GATA3 expression in an antigen-primed developing Th2 cell are not well understood. Here, we describe an unexpected role for Blimp-1, a transcriptional repressor that constrains autoimmunity, as an upstream promoter of GATA3 expression that is critical for Th2 cell development in the lung to inhaled but not systemically delivered allergens but is dispensable for TFH function and IgE production. Mechanistically, Blimp-1 acts through Bcl6, leading to increased GATA3 expression in lung Th2 cells. Surprisingly, the anti-inflammatory cytokine IL-10, but not the pro-inflammatory cytokines IL-6 or IL-21, is required via STAT3 activation to up-regulate Blimp-1 and promote Th2 cell development. These data reveal a hitherto unappreciated role for an IL-10-STAT3-Blimp-1 circuit as an initiator of an inflammatory Th2 response in the lung to allergens. Thus, Blimp-1 in a context-dependent fashion can drive inflammation by promoting rather than terminating effector T cell responses.

Human B-1 Cells and B-1 Cell Antibodies Change With Advancing Age.

Age-related deficits in the immune system have been associated with an increased incidence of infections, autoimmune diseases, and cancer. Human B cell populations change quantitatively and qualitatively in the elderly. However, the function of human B-1 cells, which play critical anti-microbial and housekeeping roles, have not been studied in the older age population. In the present work, we analyzed how the frequency, function and repertoire of human peripheral blood B-1 cells (CD19+CD20+CD27+CD38low/intCD43+) change with age. Our results show that not only the percentage of B-1 cells but also their ability to spontaneously secrete IgM decreased with age. Further, expression levels of the transcription factors XBP-1 and Blimp-1 were significantly lower, while PAX-5, characteristic of non-secreting B cells, was significantly higher, in healthy donors over 65 years (old) as compared to healthy donors between 20 and 45 years (young). To further characterize the B-1 cell population in older individuals, we performed single cell sequencing analysis of IgM heavy chains from healthy young and old donors. We found reduced repertoire diversity of IgM antibodies in B-1 cells from older donors as well as differences in usage of certain VH and DH specific genes, as compared to younger. Overall, our results show impairment of the human B-1 cell population with advancing age, which might impact the quality of life and onset of disease within the elderly population.

B lymphocyte-induced maturation protein 1 controls TH9 cell development, IL-9 production, and allergic inflammation.

BACKGROUND: The transcriptional repressor B lymphocyte-induced maturation protein 1 (Blimp-1) has a key role in terminal differentiation in various T-cell subtypes. However, whether Blimp-1 regulates TH9 differentiation and its role in allergic inflammation are unknown. OBJECTIVE: We aimed to investigate the role of Blimp-1 in TH9 differentiation and in the pathogenesis of allergic airway inflammation. METHODS: In vitro TH9 differentiation, flow cytometry, ELISA, and real-time PCR were used to investigate the effects of Blimp-1 on TH9 polarization. T cell-specific Blimp-1-deficient mice, a model of allergic airway inflammation, and T-cell adoptive transfer to recombination-activating gene 1 (Rag-1)-/- mice were used to address the role of Blimp-1 in the pathogenesis of allergic inflammation. RESULTS: We found that Blimp-1 regulates TH9 differentiation because deleting Blimp-1 increased IL-9 production in CD4+ T cells in vitro. In addition, we showed that in T cell-specific Blimp-1-deficient mice, deletion of Blimp-1 in T cells worsened airway disease, and this worsening was inhibited by IL-9 neutralization. In asthmatic patients CD4+ T cells in response to TGF-ß plus IL-4 increased IL-9 expression and downregulated Blimp-1 expression compared with expression in healthy control subjects. Blimp-1 overexpression in human TH9 cells inhibited IL-9 expression. CONCLUSION: Blimp-1 is a pivotal negative regulator of TH9 differentiation and controls allergic inflammation.

Análise da forma fosforilada do fator de choque térmico 1 (pHSF 1) em carcinomas de células escamosas de língua oral / Analysis of the phosphorylated form of heat shock factor 1 (pHSF 1) in oral tongue squamous cell carcinomas

O carcinoma de células escamosas de língua oral (CCELO) apresenta altas taxas de morbimortalidade, apesar dos avanços recentes no tratamento das neoplasias. Assim, várias pesquisas vêm tentando detectar alterações morfológicas ou identificar biomarcadores que possam apresentar poder preditivo de recidiva e metástase e novas estratégias e/ou opções terapêuticas mais individualizadas com intuito de melhorar o prognóstico destes pacientes. O fator do choque térmico 1 (HSF1) atua de diferentes formas na progressão tumoral, favorecendo o surgimento, desenvolvimento e invasividade tumoral e sua superexpressão vem sendo pesquisada em neoplasias. Esta pesquisa objetivou analisar se a forma fosforilada do fator de choque térmico 1 (p-HSF1) exerce alguma influência na patogênese do CCELO. Foi realizado um estudo imunoistoquímico em 69 casos de CCELO, verificando-se a expressão do p-HSF1 e correlacionado esta imunoexpressão com alguns parâmetros clinicopatológicos e sobrevida dos pacientes. Foi avaliado e comparado o escore de imunopositividade do p-HSF1 entre CCELO e mucosa oral normal (MON) e esta expressão foi ainda correlacionada aos sistemas de gradação histológica propostos por Brandwein-Gensler et al. (2005) e pelo modelo BD (ALMANGUSH et al., 2014). As curvas de associação de análise de sobrevida aos outros parâmetros foram realizadas pelo método Kaplan Meier e as diferenças dessas curvas submetidas ao teste log-rank (p<0,05). Verificou-se maior escore de imunoexpressão (p<0,001) de p-HSF1 em CCELOs em relação a MON, sugerindo que esse fator pode influenciar a patogênese destes tumores. A imunoexpressão do p-HSF1 não foi associada aos parâmetros clinicopatológicos pesquisados nesta amostra. O tamanho do tumor (T) T3/T4 foi associado ao alto risco tanto pelo sistema de Brandwein-Gensler et al. (2005) quanto pelo modelo BD (ALMANGUSH et al., 2014), sugerindo que tumores maiores podem ser associados a piores parâmetros histopatológicos. Os resultados da análise por meio do método BD, mostraram relevância prognóstica, uma vez que pacientes classificados como de alto risco por este sistema, foram associados a uma menor sobrevida global e maior número de óbitos, sugerindo sua possível inclusão como uma ferramenta útil na determinação do prognóstico de pacientes com CCELO (AU).

The squamous cell carcinoma (SCC) of the oral tongue presents morbimortality high levels although recent achievements of malignancies treatment. This way, a lot of researches are trying to detect morphological alterations or identify biomarkers that may present recurrence prediction power and metastasis and new strategies and/or more individualized therapeutic options in order to improve the prognosis of these patients. The Heat shock factor 1 (HSF1) acts in different ways of tumoral progressing, facilitating the appearance, development and tumoral invasiveness and its overexpression has been researched in malignancies. This research had the aim to analize if the phosphorylated form of Heat shock factor 1 (p-HSF1) carries some influence in the SCC of the oral tongue pathogenesis. There was an immunohistochemical study in 69 cases of oral tongue squamous cell carcinoma observing the p-HSF1 expression and correlating this immunoexpression with some clinicopathological parameters and patients' survival. It was evaluated and compared the immunohistochemical score of the p-HSF1 between the squamous cell carcinoma (SCC) of the oral tongue and normal oral mucosa (MON) and this expression was correlated to the histological gradation systems proposed by Brandwein-Gensler et al. (2005) and by the model BD (ALMANGUSH et al., 2014). Survival analysis of association curves with the other parameters were carried out with the Kaplan Meier method and the differences of these curves submitted to the test logrank (p<0,05). It was found a bigger immunoexpression score (p<0,001) of p-HSF1 in squamous cell carcinoma (SCC) of the oral tongue in relation to the MON, suggesting this factor may influence the tumors pathogenesis.. The tumor size ( T ) T3/ T4 was associated to the high risk not only by system of Brandwein-Gensler et al. (2005) as by model BD (ALMANGUSH et al., 2014), suggesting bigger tumors may be associated to worse histopathological parameters. The analysis result through the BD method, showed prognostic implication, since as patients classified as high risk by this system were associated to a smaller global survival and bigger death number, suggesting its possible inclusion as a useful tool in the prognosis determination of patients with squamous cell carcinoma (SCC) of the oral tongue (AU).

New Insights into the Genetic Basis of Monge's Disease and Adaptation to High-Altitude.

Human high-altitude (HA) adaptation or mal-adaptation is explored to understand the physiology, pathophysiology, and molecular mechanisms that underlie long-term exposure to hypoxia. Here, we report the results of an analysis of the largest whole-genome-sequencing of Chronic Mountain Sickness (CMS) and nonCMS individuals, identified candidate genes and functionally validated these candidates in a genetic model system (Drosophila). We used PreCIOSS algorithm that uses Haplotype Allele Frequency score to separate haplotypes carrying the favored allele from the noncarriers and accordingly, prioritize genes associated with the CMS or nonCMS phenotype. Haplotypes in eleven candidate regions, with SNPs mostly in nonexonic regions, were significantly different between CMS and nonCMS subjects. Closer examination of individual genes in these regions revealed the involvement of previously identified candidates (e.g., SENP1) and also unreported ones SGK3, COPS5, PRDM1, and IFT122 in CMS. Remarkably, in addition to genes like SENP1, SGK3, and COPS5 which are HIF-dependent, our study reveals for the first time HIF-independent gene PRDM1, indicating an involvement of wider, nonHIF pathways in HA adaptation. Finally, we observed that down-regulating orthologs of these genes in Drosophila significantly enhanced their hypoxia tolerance. Taken together, the PreCIOSS algorithm, applied on a large number of genomes, identifies the involvement of both new and previously reported genes in selection sweeps, highlighting the involvement of multiple hypoxia response systems. Since the overwhelming majority of SNPs are in nonexonic (and possibly regulatory) regions, we speculate that adaptation to HA necessitates greater genetic flexibility allowing for transcript variability in response to graded levels of hypoxia.

Galectin-3 mediates IL-4-induced survival and differentiation of B cells: functional cross-talk and implications during Trypanosoma cruzi infection.

The role of transcription factors in B cell survival and differentiation has been delineated during the last years. However, little is known about the intermediate signals and the intracellular pathways that control these events. In this study, we provide evidence both in vitro and in vivo, showing that galectin-3 (Gal-3), a beta-galactoside-binding protein, is a critical mediator of B cell differentiation and survival. Although Gal-3 is not expressed in resting B cells from normal mice, its expression is markedly induced after activation with stimuli such as IL-4 and CD40 cross-linking. These signals promote survival and block the final differentiation of these cells, thus allowing the rising of a memory B cell phenotype. In addition, Gal-3 is expressed in B cells from Trypanosoma cruzi-infected mice, which received signals for activation and differentiation in vivo. By using an antisense strategy, we determined that Gal-3 is a critical signal mediating the effects of IL-4 on B cell fate. Blockade of intracellular Gal-3 in vitro abrogated IL-4-induced survival of activated B cells, favoring the differentiation toward a plasma cell pathway. Moreover, B cells with restrained endogenous Gal-3 expression failed to down-regulate the Blimp-1 transcription factor after IL-4 stimulation. Finally, inhibition of Gal-3 in vivo skewed the balance toward plasma cell differentiation, which resulted in increased Ig production and parasite clearance during T. cruzi infection. Thus, the present study provides evidence of a novel role for Gal-3 as an intracellular mediator of B cell survival and a checkpoint in IL-4-induced B cell commitment toward a memory phenotype.