15 research outputs found

    Búsqueda y selección de una proteasa fúngica con potencial aplicación en la restauración de documentos históricos en el archivo de bogotá

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    Título en ingles: Screening for a fungal protease with potential in the biorestoration of historical valuable documents in Bogota Archive Resumen: Se ha buscado y seleccionado sistemáticamente una proteasa que pudiese ser usada en la eliminación “limpia” de encolantes sobre soportes documentales con valor de patrimonio histórico de forma eficiente y económica, a partir de la colección de hongos filamentosos del Archivo de Bogotá. De 74 morfotipos viables evaluados sobre placas selectivas, 32 morfotipos presentaron formación de halos de hidrólisis evidentes sobre placas diferenciales. De ellos, se evaluó el perfil isoenzimático de 8 morfotipos provenientes de muestreos documentales directos y de 2 morfotipos proteolíticos promisorios provenientes de un trabajo previo. Los 10 morfotipos seleccionados fueron representativos de los géneros Penicillium, Stachybotrys, Chaetomium, y Eladia. Luego de inducir la producción de proteasas extracelulares en medios líquidos diferenciales bajo tres fases de fermentación, se realizaron isoelectroénfoques analíticos tendientes a la observación de isoformas en el gradiente de pH establecido (3.0-10.0). Solo los morfotipos 8D (Chaetomium sp.) y 21D (Eladia saccula) presentaron una isoforma alcalina extrema, de puntos isoeléctricos 8.5 y 8.8, respectivamente, susceptible de selección con miras a su purificación y caracterización parcial de forma económica y eficiente. Los demás morfotipos, representativos de los géneros Penicillium sp., y Stachybotrys sp., presentaron unicamente isoformas proteolíticas en el rango acido de pH con puntos isoeléctricos que oscilan entre 4.0 y 5.0. Palabras clave: biodeterioro; hongo filamentoso; proteasa; halo de hidrólisis; punto isoeléctrico. Abstract: Studies on a protease as an efficient, environmental friendly and relatively economical remover of residual proteins for historical valuable documents were performed and was selected for this work, from the filamentous fungi collection of the Bogota Archive. 32 morphotypes of 74 evaluated show hydrolytic activities over differential solid media. From them, 8 morphotypes obtained directly from documental samples and representative of the genera Penicillium and Stachybotrys were selected and their isoenzyme profile were tested. Also 2 previous morphotypes with promisorius proteolytic activities and representative of the genera Chaetomium and Eladia were analysed. Extracelullar proteases production was induced in differential liquid media on three fermentation steps and analitycal isoelectrofocusing were performed over pH 3.0-10.0 ranges. Only the morphotypes 8D (Chaetomium sp.), and 21D (Eladia sp.), showed an alkaline isoform with pIs 8.5 and 8.8, respectly, suceptible of selection for its purification and characterization through efficient and economical way. The others morphotypes only showed acid isoforms with pIs in the range of 4.0 and 5.0. Key words: biodeterioration; filamentous fungi; protease; hydrolytic halo; isoelectric poin

    Resolving the intersection of HIV and F-actin in the context of cell-cell viral spread

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    HIV has evolved elaborate mechanisms to manipulate the host cell’s actin cytoskeleton. This supports specific steps of the viral life cycle but also leads to cell-type specific changes in leukocyte shape and behaviour that promote overall spread of the infection. In particular, actin manipulation is important for direct cell-cell transfer of HIV (CCTH), which is now recognized as a highly efficient mode of viral spread.This study aimed to further resolve the molecular players and mechanisms involved in this process.Through the use of CRISPR–Cas9-mediated gene editing, herein we systematically interrogated the loss-of-function phenotype of over 50 cytoskeletal regulators, in both HIV-donor and target cells during CCTH. This was then combined with a portfolio of complementary assays ranging from live cell microscopy through to the ultrastructural resolution of focused ion beam scanning electron microscopy. This approach identified several core actin regulators to be required on both sides of viral transfer, including the Rho-GTPases Cdc42/Rac1 (signalling), upstream of the Arp2/3 complex (actin nucleator), and Profilin (which indirectly supports F-actin elongation, e.g. via Formins). In infected myeloid cells, Cdc42-Arp2/3 and Formins collaborated to form distinct “HIV-Filopodia”, which were shown to be important for CCTH. The overall findings of this work support that, while HIV uses diverse strategies to influence numerous cytoskeletal targets, there is a high tolerance for the individual loss of many manipulated regulators in the context of CCTH. However, core regulators that secure the cellular ability to mediate F-actin polymerization remain essential to this process, in particular via their contribution to cortical F-actin membrane protrusions that facilitate intercellular contacts and later maturation of the virological synapse. To conclude, we have mapped a landscape of complex interactions between HIV and the actin cytoskeleton. This not only builds on our understanding of F-actin regulation in cells of our immune system but will also facilitate the continued development of host-directed therapeutics for lentiviral and/or other pathogenic infections

    Búsqueda y selección de una proteasa fúngica con potencial aplicación en la restauración de documentos históricos en el Archivo de Bogotá

    No full text
    Studies on a protease as an efficient, environmental friendly and relatively economical remover of residual proteins for historical valuable documents were performed and was selected for this work, from the filamentous fungi collection of the Bogota Archive. 32 morphotypes of 74 evaluated show hydrolytic activities over differential solid media. From them, 8 morphotypes obtained directly from documental samples and representative of the genera Penicillium and Stachybotrys were selected and their isoenzyme profile were tested. Also 2 previous morphotypes with promisorius proteolytic activities and representative of the genera Chaetomium and Eladia were analysed. Extracelullar proteases production was induced in differential liquid media on three fermentation steps and analitycal isoelectrofocusing were performed over pH 3.0-10.0 ranges. Only the morphotypes 8D (Chaetomium sp.), and 21D (Eladia sp.), showed an alkaline isoform with pIs 8.5 and 8.8, respectly, suceptible of selection for its purification and characterization through efficient and economical way. The others morphotypes only showed acid isoforms with pIs in the range of 4.0 and 5.0.Se ha buscado y seleccionado sistemáticamente una proteasa que pudiese ser usada en la eliminación limpia de encolantes sobre soportes documentales con valor de patrimonio histórico de forma eficiente y económica, a partir de la colección de hongos filamentosos del Archivo de Bogotá. De 74 morfotipos viables evaluados sobre placas selectivas, 32 morfotipos presentaron formación de halos de hidrólisis evidentes sobre placas diferenciales. De ellos, se evaluó el perfil isoenzimático de 8 morfotipos provenientes de muestreos documentales directos y de 2 morfotipos proteolíticos promisorios provenientes de un trabajo previo. Los 10 morfotipos seleccionados fueron representativos de los géneros Penicillium, Stachybotrys, Chaetomium, y Eladia. Luego de inducir la producción de proteasas extracelulares en medios líquidos diferenciales bajo tres fases de fermentación, se realizaron isoelectroénfoques analíticos tendientes a la observación de isoformas en el gradiente de pH establecido (3.0-10.0). Solo los morfotipos 8D (Chaetomium sp.) y 21D (Eladia saccula) presentaron una isoforma alcalina extrema, de puntos isoeléctricos 8.5 y 8.8, respectivamente, susceptible de selección con miras a su purificación y caracterización parcial de forma económica y eficiente. Los demás morfotipos, representativos de los géneros Penicillium sp., y Stachybotrys sp., presentaron unicamente isoformas proteolíticas en el rango acido de pH con puntos isoeléctricos que oscilan entre 4.0 y 5.0

    LRRC15 suppresses SARS-CoV-2 infection and controls collagen production

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    The coronavirus pandemic has given everyone in society an education on the harms of spread of respiratory illness. Young healthy athletes are far less likely to suffer severe adverse consequences of viral illnesses than the elderly and frail, but they are not completely immune. Chronic fatigue (overtraining) is an uncommon outcome and myocarditis a rare one, but they both warrant due consideration. It is, therefore, a sensible individual strategy to 'stay home when sick' if only for these risks. Traditionally though, athletes have tended to push through (train and play when ill) because of competing concerns, such as key events/matches and 'not wanting to let teammates down'. Data from both low COVID-19 and high COVID-19 countries show that the number of cardiovascular deaths in a society correlates with the number of respiratory deaths at the same time, further linking respiratory viruses to cardiovascular deaths. We are now more aware of public health obligations to prevent the spread of respiratory illnesses, in particular to protect the more vulnerable members the community. This hopefully will correspond with a change in the culture of sport to one where it is considered 'the right thing to do', to 'stay home when sick'

    Patients with treated indolent lymphomas immunized with BNT162b2 have reduced anti‐spike neutralizing IgG to SARS‐CoV‐2 variants, but preserved antigen‐specific T cell responses

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    Patients with indolent lymphoma undertaking recurrent or continuous B cell suppression are at risk of severe COVID-19. Patients and healthy controls (HC; N=13) received 2 doses of BNT162b2: Follicular Lymphoma (FL; N=35) who were treatment naïve (TN; N=11) or received immunochemotherapy (ICT; N=23) and Waldenström's Macroglobulinemia (WM; N=37) including TN (N=9), ICT (N=14), or treated with Bruton's Tyrosine Kinase inhibitors (BTKi; N=12). Anti-spike IgG was determined by a high-sensitivity flow-cytometric assay, in addition to live-virus neutralization. Antigen-specific T cells were identified by co-expression of CD69/CD137 and CD25/CD134 on T cells. A subgroup (N=29) were assessed for third mRNA vaccine response, including omicron neutralization. One month after second BNT162b2, median anti-spike IgG mean fluorescence intensity (MFI) in FL ICT patients (9977) was 25-fold lower than TN (245898) and HC (228255, p=0.0002 for both). Anti-spike IgG correlated with lymphocyte count (r=0.63; p=0.002), and time from treatment, (r=0.56; p=0.007) on univariate analysis, but only with lymphocyte count on multivariate analysis (p=0.03). In the WM cohort, median anti-spike IgG MFI in BTKi patients (39039) was reduced compared to TN (220645, p=0.0008) and HC (p<0.0001). Anti-spike IgG correlated with neutralization of the delta variant (r=0.62, p<0.0001). Median neutralization titer for WM BTKi (0) was lower than HC (40, p<0.0001) for early-clade and delta. All cohorts had functional T cell responses. Median anti-spike IgG decreased 4-fold from second to third dose (p=0.004). Only 5/29 poor initial responders assessed after third vaccination demonstrated seroconversion and improvement in neutralization activity, including to the omicron variant. This article is protected by copyright. All rights reserved

    Fibroblast-expressed LRRC15 is a receptor for SARS-CoV-2 spike and controls antiviral and antifibrotic transcriptional programs.

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    Although ACE2 is the primary receptor for Severe Acute Respiratory Syndrome Coronavirus 2 (SARS-CoV-2) infection, a systematic assessment of host factors that regulate binding to SARS-CoV-2 spike protein has not been described. Here, we use whole-genome CRISPR activation to identify host factors controlling cellular interactions with SARS-CoV-2. Our top hit was a TLR-related cell surface receptor called leucine-rich repeat-containing protein 15 (LRRC15). LRRC15 expression was sufficient to promote SARS-CoV-2 spike binding where they form a cell surface complex. LRRC15 mRNA is expressed in human collagen-producing lung myofibroblasts and LRRC15 protein is induced in severe Coronavirus Disease 2019 (COVID-19) infection where it can be found lining the airways. Mechanistically, LRRC15 does not itself support SARS-CoV-2 infection, but fibroblasts expressing LRRC15 can suppress both pseudotyped and authentic SARS-CoV-2 infection in trans. Moreover, LRRC15 expression in fibroblasts suppresses collagen production and promotes expression of IFIT, OAS, and MX-family antiviral factors. Overall, LRRC15 is a novel SARS-CoV-2 spike-binding receptor that can help control viral load and regulate antiviral and antifibrotic transcriptional programs in the context of COVID-19 infection

    Maintenance of Broad Neutralising Antibodies and Memory B Cells 12 Months Post-Infection Is Predicted by SARS-CoV-2 Specific CD4+ T Cell Responses

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    Understanding the long-term maintenance of SARS-CoV-2 immunity is critical for prediction of protection against reinfection. In a cohort of 24 participants, the association of disease severity and early immunological measurements on the maintenance of humoral immune responses 12 months post-infection were examined. All severely affected participants maintained a stable subset of SARS-CoV-2 receptor-binding domain (RBD) specific memory B cells (MBCs) and good neutralising antibody breadth against the majority of the variants of concern, including the Delta variant. Modelling these immune responses on vaccine efficacy data indicated a level equivalent to a vaccine efficacy of approximately 45-76% against symptomatic reinfection (variant dependent). Overall, these findings indicate durable humoral responses in most participants, provide an estimate of the level of protection and identifies the magnitude and phenotype of baseline antigen-specific CD4+ T cell response as a predictor of maintenance of both antibody neutralisation breadth and RBD-specific MBC levels at 12 months post-infection.Funding: The Kirby Institute is funded by the Australian Government Department of Health and Ageing. The views expressed in this publication do not necessarily represent the position of the Australian Government. Research reported in this publication was supported by Snow Medical Foundation as an investigator-initiated study. The content is solely the responsibility of the authors. RAB, MM, CR and ARL are fellows funded by National Health and Medical Research Council (NHMRC). MWAC is in part funded by the Research Infrastructure Programme of UNSW.Declaration of Interests: The authors declare no competing interests.Ethics Approval Statement: The protocol was approved by the Human Research Ethics Committees of the Northern Sydney Local Health District and the University of New South Wales, NSW Australia (ETH00520) and was conducted according to the Declaration of Helsinki and International Conference on Harmonization Good Clinical Practice (ICH/GCP) guidelines and local regulatory requirements. Written informed consent was obtained from all participants before study procedures
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