46 research outputs found

    Comparable cellular and humoral immunity upon homologous and heterologous COVID-19 vaccination regimens in kidney transplant recipients

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    BackgroundKidney transplant recipients (KTRs) are at high risk for a severe course of coronavirus disease 2019 (COVID-19); thus, effective vaccination is critical. However, the achievement of protective immunogenicity is hampered by immunosuppressive therapies. We assessed cellular and humoral immunity and breakthrough infection rates in KTRs vaccinated with homologous and heterologous COVID-19 vaccination regimens.MethodWe performed a comparative in-depth analysis of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2)–specific T-cell responses using multiplex Fluorospot assays and SARS-CoV-2-specific neutralizing antibodies (NAbs) between three-times homologously (n = 18) and heterologously (n = 8) vaccinated KTRs.ResultsWe detected SARS-CoV-2-reactive T cells in 100% of KTRs upon third vaccination, with comparable frequencies, T-cell expression profiles, and relative interferon γ and interleukin 2 production per single cell between homologously and heterologously vaccinated KTRs. SARS-CoV-2-specific NAb positivity rates were significantly higher in heterologously (87.5%) compared to homologously vaccinated (50.0%) KTRs (P < 0.0001), whereas the magnitudes of NAb titers were comparable between both subcohorts after third vaccination. SARS-CoV-2 breakthrough infections occurred in equal numbers in homologously (38.9%) and heterologously (37.5%) vaccinated KTRs with mild-to-moderate courses of COVID-19.ConclusionOur data support a more comprehensive assessment of not only humoral but also cellular SARS-CoV-2-specific immunity in KTRs to provide an in-depth understanding about the COVID-19 vaccine–induced immune response in a transplant setting

    BLOOM: A 176B-Parameter Open-Access Multilingual Language Model

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    Large language models (LLMs) have been shown to be able to perform new tasks based on a few demonstrations or natural language instructions. While these capabilities have led to widespread adoption, most LLMs are developed by resource-rich organizations and are frequently kept from the public. As a step towards democratizing this powerful technology, we present BLOOM, a 176B-parameter open-access language model designed and built thanks to a collaboration of hundreds of researchers. BLOOM is a decoder-only Transformer language model that was trained on the ROOTS corpus, a dataset comprising hundreds of sources in 46 natural and 13 programming languages (59 in total). We find that BLOOM achieves competitive performance on a wide variety of benchmarks, with stronger results after undergoing multitask prompted finetuning. To facilitate future research and applications using LLMs, we publicly release our models and code under the Responsible AI License

    AREG contributes to the diminished PICD of neonatal monocytes by EGFR-mediated apoptosis suppression

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    Neonates are highly susceptible to microbial infections, resulting in nearly 1 million neonatal deaths per year. This predisposition is particularly referable to distinct differences between the immune system of adults and neonates. The process of inflammation is usually triggered as a protective response to infection or tissue injury. The accurate resolution of the inflammatory response is essential to return to tissue homeostasis since a prolonged inflammation with ongoing cytokine release can result in tissue damage, organ dysfunctions and mortality. This is of particular importance for newborns, since various neonatal diseases, including periventricular leukomalacia, necrotizing enterocolitis or bronchopulmonary dysplasia, are characterized by sustained inflammation. One factor known to control length and extent of the inflammatory response, is the regulation of effector cell apoptosis. A special type of apoptosis is the phagocytosis-induced cell death (PICD) of phagocytic immune cells. Previous studies demonstrated that PICD is less frequently triggered in neonatal monocytes than in adult monocytes. Hence, a rescue of monocyte PICD could be a potential therapeutic approach to target the sustained inflammation in neonates. The EGF receptor is capable of blocking the initiation of apoptosis upon activation by its specific ligands. One ligand is the cytokine amphiregulin (AREG), which is increasingly shedded in response to bacterial infection and was shown to mediate apoptosis resistance. Therefore, it was hypothesized that AREG might contribute to the reduced PICD of neonatal monocytes by affecting the apoptosis signaling of monocytes. In this study, a well-established in vitro E. coli infection model was used to analyze PICD in primary monocytes from peripheral (PBMO) or cord blood (CBMO). The results indicate that CBMO show remarkably higher AREG surface expression as well as soluble levels in response to infection which could function as anti-apoptotic stimulus. Flow cytometry experiments were conducted to analyze intrinsic and extrinsic apoptosis signaling in dependence on AREG. Strikingly, AREG was proven to affect both pathways through EGFR downstream trafficking. With regard to extrinsic apoptosis, AREG increases intracellular MMP-2 and MMP-9 levels through EGFR activation, whereby inducing cleavage of membrane-bound FasL. Intrinsic apoptosis signaling is supressed by AREG function via EGFR-mediated phosphorylation of ERK1/2, Akt and BAD, resulting in increased intracellular Bcl-2 and Bcl-XL levels and decreased cleavage of pro-caspase-9 and -3. Furthermore, the results indicate that AREG may have regulatory function on T cells, which are of special importance for the immune response as they perform key effector functions during inflammation. AREG potentially reduces T cell proliferation through the suppressed costimulatory capacity of monocytes, since surface expression of CD80, CD86 und HLA-DR was found downregulated. The temporary presence during the newborn period might identify AREG as endogenous immune regulator. Targeting inflammatory diseases in neonates is of central clinical relevance and a better understanding of the regulatory elements involved in PICD could be essential to find new therapeutic strategies. Inhibition of AREG rescued the PICD of neonatal monocytes, thereby identifying AREG as potential target to reduce sustained inflammation in neonates

    Comparative analysis of postural control and vertical jump performance between three different measurement devices.

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    ObjectivesThe aim of this study was to examine the concurrent validity of the HUMAC Balance System (HBS) and Balance Trainer BTG4 (BTG) in comparison to a laboratory-grade force platform (FP) for postural control (PC) and vertical jump performance (VJP) assessment. In addition, reliability of the three devices was measured for PC.MethodsOverall 22 participants (age = 37.8 ± 13.3 years; gender = 9 male, 13 female; height = 174.1 ± 10.5 cm; body mass = 75.3 ± 17.6 kg) were recruited to participate. Double and single leg standing balance tests with eyes open or closed and counter movement jumps (CMJ) were performed on two separate occasions. Reliability and concurrent validity for COP parameters and VJP were examined using intraclass correlation coefficients (ICC), Bland-Altman plots (BAP), standard error of measurement (SEM) and minimum detectable change (MDC).ResultsCOP path length test-retest reliability was predominantly good to excellent for all three devices (ICC = 0.80-0.95). SEM and MDC values were high for all plates (SEM% = 8.0-15.2; MDC% = 22.8-44.5), with the HBS MDC values higher than the KIS and BTG in three of the four trials. ICC scores for concurrent validity were good to excellent for the BTG (ICC = 0.76-0.93) and moderate to good for the HBS (0.49-0.83). Band-Altman plots revealed a systematic bias for the HBS towards higher COP path length values under all conditions and for the BTG in two out of four trials towards lower values. Validity of VJP was excellent for the BTG (ICC = 1.0) and poor for the HBS (0.34), with a systematic bias towards lower values.ConclusionThe comparative analysis of PC and VJP revealed reliable and valid results for the BTG in comparison to a laboratory-grade force plate. The HBS showed reliable results for PC assessment with restrictions regarding its validity. Results of VJP showed that the HBS revealed deficits in the assessment of activities that require rapid, high force movements such as jumping and running. Due to the variable results of all three devices, it is recommended not to use them interchangeably

    Amphiregulin Regulates Phagocytosis-Induced Cell Death in Monocytes via EGFR and Matrix Metalloproteinases

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    Neonates are highly susceptible to microbial infections which is partially attributable to fundamental phenotypic and functional differences between effector cells of the adult and neonatal immune system. The resolution of the inflammation is essential to return to tissue homeostasis, but given that various neonatal diseases, such as periventricular leukomalacia, necrotizing enterocolitis, or bronchopulmonary dysplasia, are characterized by sustained inflammation, newborns seem predisposed to a dysregulation of the inflammatory response. Targeted apoptosis of effector cells is generally known to control the length and extent of the inflammation, and previous studies have demonstrated that phagocytosis-induced cell death (PICD), a special type of apoptosis in phagocytic immune cells, is less frequently triggered in neonatal monocytes than in adult monocytes. We concluded that a rescue of monocyte PICD could be a potential therapeutic approach to target sustained inflammation in neonates. The EGFR ligand amphiregulin (AREG) is shed in response to bacterial infection and was shown to mediate cellular apoptosis resistance. We hypothesized that AREG might contribute to the reduced PICD of neonatal monocytes by affecting apoptosis signaling. In this study, we have examined a cascade of signaling events involved in extrinsic apoptosis by using a well-established in vitro E. coli infection model in monocytes from human peripheral blood (PBMO) and cord blood (CBMO). We found that CBMO shows remarkably higher pro-AREG surface expression as well as soluble AREG levels in response to infection as compared to PBMO. AREG increases intracellular MMP-2 and MMP-9 levels and induces cleavage of membrane-bound FasL through engagement with the EGF receptor. Our results demonstrate that loss of AREG rescues PICD in CBMO to the level comparable to adult monocytes. These findings identify AREG as a potential target for the prevention of prolonged inflammation in neonates

    PONE-D-16-46185_R2 cumulative data

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    Metalloproteinases TACE and MMP-9 Differentially Regulate Death Factors on Adult and Neonatal Monocytes After Infection with <i>Escherichia coli</i>

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    Background: Cleaving ligands and receptors of the tumor necrosis factor (TNF) superfamily can critically regulate the induction of apoptosis. Matrix metalloproteinases (MMPs) such as MMP-9 and tumor necrosis factor-&#945;-converting enzyme (TACE) have been shown to cleave CD95-Ligand (CD95L) and TNF/(TNF receptor-1) TNFR1 which induce phagocytosis induced cell death (PICD) in adult monocytes. This process is reduced in neonatal monocytes. Methods: Here we tested in vitro, whether Escherichia coli infection mounts for activation of MMP-9 and TACE in monocytes and whether this process regulates PICD. Results: The surface expression of TACE was most prominent on infected adult monocytes. In contrast, surface presentation of MMP-9 was highest on infected neonatal monocytes. Selective blocking of MMP-9 decreased CD95L secretion, while inhibition of TACE left CD95L secretion unaltered. Blocking of MMP-9 increased surface CD95L (memCD95L) expression on infected neonatal monocytes to levels comparable to infected adult monocytes. Moreover, MMP-9 inhibition raised PICD of infected neonatal monocytes to levels observed for infected adult monocytes. In contrast, TACE inhibition decreased PICD in infected monocytes. Addition of extracellular TNF effectively induced memCD95L presentation and PICD of adult monocytes and less of neonatal monocytes. Conclusion: MMP-9 activity is crucial for downregulating cell-contact dependent PICD in E. coli infected neonatal monocytes. By this mechanism, MMP-9 could contribute to reducing sustained inflammation in neonates

    Data from: Reduced PICD in monocytes mounts altered neonate immune response to Candida albicans

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    Background: Invasive fungal infections with Candida albicans (C. albicans) occur frequently in extremely low birthweight (ELBW) infants and are associated with poor outcome. Phagocytosis of C.albicans initializes apoptosis in monocytes (phagocytosis induced cell death, PICD). PICD is reduced in neonatal cord blood monocytes (CBMO). Hypothesis: Phagocytosis of C. albicans causes PICD which differs between neonatal monocytes (CBMO) and adult peripheral blood monocytes (PBMO) due to lower stimulation of TLR-mediated immune responses. Methods: The ability to phagocytose C. albicans, expression of TLRs, the induction of apoptosis (assessment of sub-G1 and nick-strand breaks) were analyzed by FACS. TLR signalling was induced by agonists such as lipopolysaccharide (LPS), Pam3Cys, FSL-1 and Zymosan and blocked (neutralizing TLR2 antibodies and MYD88 inhibitor). Results: Phagocytic indices of PBMO and CBMO were similar. Following stimulation with agonists and C. albicans induced up-regulation of TLR2 and consecutive phosphorylation of MAP kinase P38 and expression of TNF-alpha which were stronger on PBMO compared to CBMO (p < 0.005). Downstream, TLR2 signalling initiated caspase-3-dependent PICD which was found reduced in CBMO (p < 0.05 vs PBMO). Conclusion: Our data suggest direct involvement of TLR2-signalling in C. albicans-induced PICD in monocytes and an alteration of this pathway in CBMO

    Data Sets DOI10.1371journal.pone.0166648

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