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  1. Article ; Online: Deciphering the code of viral-host adaptation through maximum entropy models

    Di Gioacchino, Andrea / Greenbaum, Benjamin D / Monasson, Remi / Cocco, Simona

    bioRxiv

    Abstract: ... single, di- and tri- nucleotide usage, which can be trained from viral sequences that infect a given host ...

    Abstract Understanding how the genome of a virus evolves depending on the host it infects is an important question that challenges our knowledge about several mechanisms of host-pathogen interactions, including mutational signatures, innate immunity, and codon optimization. A key facet of this general topic is the study of viral genome evolution after a host-jumping event, a topic which has experienced a surge in interest due to the fight against emerging pathogens such as SARS-CoV-2. In this work, we tackle this question by introducing a new method to learn Maximum Entropy Nucleotide Bias models (MENB) reflecting single, di- and tri- nucleotide usage, which can be trained from viral sequences that infect a given host. We show that both the viral family and the host leave a fingerprint in nucleotide usages which MENB models decode. When the task is to classify both the host and the viral family for a sequence of unknown viral origin MENB models outperform state of the art methods based on deep neural networks. We further demonstrate the generative properties of the proposed framework, presenting an example where we change the nucleotide composition of the 1918 H1N1 Influenza A sequence without changing its protein sequence, while manipulating the nucleotide usage, by diminishing its CpG content. Finally we consider two well-known cases of zoonotic jumps, for the H1N1 Influenza A and for the SARS-CoV-2 viruses, and show that our method can be used to track the adaptation to the new host and to shed light on the more relevant selective pressures which have acted on motif usage during this process. Our work has wide-ranging applications, including integration into metagenomic studies to identify hosts for diverse viruses, surveillance of emerging pathogens, prediction of synonymous mutations that effect immunogenicity during viral evolution in a new host, and the estimation of putative evolutionary ages for viral sequences in similar scenarios. Additionally, the computational framework introduced here can be used to assist vaccine design by tuning motif usage with fine-grained control.
    Keywords covid19
    Language English
    Publishing date 2023-10-30
    Publisher Cold Spring Harbor Laboratory
    Document type Article ; Online
    DOI 10.1101/2023.10.28.564530
    Database COVID19

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  2. Article ; Online: A transfer-learning approach to predict antigen immunogenicity and T-cell receptor specificity.

    Bravi, Barbara / Di Gioacchino, Andrea / Fernandez-de-Cossio-Diaz, Jorge / Walczak, Aleksandra M / Mora, Thierry / Cocco, Simona / Monasson, Rémi

    eLife

    2023  Volume 12

    Abstract: Antigen immunogenicity and the specificity of binding of T-cell receptors to antigens are key properties underlying effective immune responses. Here we propose diffRBM, an approach based on transfer learning and Restricted Boltzmann Machines, to build ... ...

    Abstract Antigen immunogenicity and the specificity of binding of T-cell receptors to antigens are key properties underlying effective immune responses. Here we propose diffRBM, an approach based on transfer learning and Restricted Boltzmann Machines, to build sequence-based predictive models of these properties. DiffRBM is designed to learn the distinctive patterns in amino-acid composition that, on the one hand, underlie the antigen's probability of triggering a response, and on the other hand the T-cell receptor's ability to bind to a given antigen. We show that the patterns learnt by diffRBM allow us to predict putative contact sites of the antigen-receptor complex. We also discriminate immunogenic and non-immunogenic antigens, antigen-specific and generic receptors, reaching performances that compare favorably to existing sequence-based predictors of antigen immunogenicity and T-cell receptor specificity.
    MeSH term(s) T-Cell Antigen Receptor Specificity ; Learning ; Amino Acids ; Cell Membrane ; Mitochondrial Membranes
    Chemical Substances Amino Acids
    Language English
    Publishing date 2023-09-08
    Publishing country England
    Document type Journal Article ; Research Support, Non-U.S. Gov't
    ZDB-ID 2687154-3
    ISSN 2050-084X ; 2050-084X
    ISSN (online) 2050-084X
    ISSN 2050-084X
    DOI 10.7554/eLife.85126
    Database MEDical Literature Analysis and Retrieval System OnLINE

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  3. Article ; Online: Retroelement decay by the exonuclease XRN1 is a viral mimicry dependency in cancer.

    Hosseini, Amir / Lindholm, Håvard T / Chen, Raymond / Mehdipour, Parinaz / Marhon, Sajid A / Ishak, Charles A / Moore, Paul C / Classon, Marie / Di Gioacchino, Andrea / Greenbaum, Benjamin / De Carvalho, Daniel D

    Cell reports

    2024  Volume 43, Issue 2, Page(s) 113684

    Abstract: Viral mimicry describes the immune response induced by endogenous stimuli such as double-stranded RNA (dsRNA) from endogenous retroelements. Activation of viral mimicry has the potential to kill cancer cells or augment anti-tumor immune responses. Here, ... ...

    Abstract Viral mimicry describes the immune response induced by endogenous stimuli such as double-stranded RNA (dsRNA) from endogenous retroelements. Activation of viral mimicry has the potential to kill cancer cells or augment anti-tumor immune responses. Here, we systematically identify mechanisms of viral mimicry adaptation associated with cancer cell dependencies. Among the top hits is the RNA decay protein XRN1 as an essential gene for the survival of a subset of cancer cell lines. XRN1 dependency is mediated by mitochondrial antiviral signaling protein and protein kinase R activation and is associated with higher levels of cytosolic dsRNA, higher levels of a subset of Alus capable of forming dsRNA, and higher interferon-stimulated gene expression, indicating that cells die due to induction of viral mimicry. Furthermore, dsRNA-inducing drugs such as 5-aza-2'-deoxycytidine and palbociclib can generate a synthetic dependency on XRN1 in cells initially resistant to XRN1 knockout. These results indicate that XRN1 is a promising target for future cancer therapeutics.
    MeSH term(s) Humans ; Retroelements ; Cell Line ; Cytosol ; Decitabine ; Exonucleases ; Neoplasms/genetics ; RNA, Double-Stranded ; Exoribonucleases ; Microtubule-Associated Proteins
    Chemical Substances Retroelements ; Decitabine (776B62CQ27) ; Exonucleases (EC 3.1.-) ; RNA, Double-Stranded ; XRN1 protein, human (EC 3.1.13.1) ; Exoribonucleases (EC 3.1.-) ; Microtubule-Associated Proteins
    Language English
    Publishing date 2024-01-22
    Publishing country United States
    Document type Journal Article
    ZDB-ID 2649101-1
    ISSN 2211-1247 ; 2211-1247
    ISSN (online) 2211-1247
    ISSN 2211-1247
    DOI 10.1016/j.celrep.2024.113684
    Database MEDical Literature Analysis and Retrieval System OnLINE

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  4. Article: Inflammatory status in pediatric sickle cell disease: Unravelling the role of immune cell subsets.

    Marchesani, Silvio / Bertaina, Valentina / Marini, Olivia / Cossutta, Matilde / Di Mauro, Margherita / Rotulo, Gioacchino Andrea / Palma, Paolo / Sabatini, Letizia / Petrone, Maria Isabella / Frati, Giacomo / Monteleone, Giulia / Palumbo, Giuseppe / Ceglie, Giulia

    Frontiers in molecular biosciences

    2023  Volume 9, Page(s) 1075686

    Abstract: Introduction: ...

    Abstract Introduction:
    Language English
    Publishing date 2023-01-10
    Publishing country Switzerland
    Document type Journal Article
    ZDB-ID 2814330-9
    ISSN 2296-889X
    ISSN 2296-889X
    DOI 10.3389/fmolb.2022.1075686
    Database MEDical Literature Analysis and Retrieval System OnLINE

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  5. Article ; Online: The Heterogeneous Landscape and Early Evolution of Pathogen-Associated CpG Dinucleotides in SARS-CoV-2.

    Di Gioacchino, Andrea / Šulc, Petr / Komarova, Anastassia V / Greenbaum, Benjamin D / Monasson, Rémi / Cocco, Simona

    Molecular biology and evolution

    2021  Volume 38, Issue 6, Page(s) 2428–2445

    Abstract: COVID-19 can lead to acute respiratory syndrome, which can be due to dysregulated immune signaling. We analyze the distribution of CpG dinucleotides, a pathogen-associated molecular pattern, in the SARS-CoV-2 genome. We characterize CpG content by a CpG ... ...

    Abstract COVID-19 can lead to acute respiratory syndrome, which can be due to dysregulated immune signaling. We analyze the distribution of CpG dinucleotides, a pathogen-associated molecular pattern, in the SARS-CoV-2 genome. We characterize CpG content by a CpG force that accounts for statistical constraints acting on the genome at the nucleotidic and amino acid levels. The CpG force, as the CpG content, is overall low compared with other pathogenic betacoronaviruses; however, it widely fluctuates along the genome, with a particularly low value, comparable with the circulating seasonal HKU1, in the spike coding region and a greater value, comparable with SARS and MERS, in the highly expressed nucleocapside coding region (N ORF), whose transcripts are relatively abundant in the cytoplasm of infected cells and present in the 3'UTRs of all subgenomic RNA. This dual nature of CpG content could confer to SARS-CoV-2 the ability to avoid triggering pattern recognition receptors upon entry, while eliciting a stronger response during replication. We then investigate the evolution of synonymous mutations since the outbreak of the COVID-19 pandemic, finding a signature of CpG loss in regions with a greater CpG force. Sequence motifs preceding the CpG-loss-associated loci in the N ORF match recently identified binding patterns of the zinc finger antiviral protein. Using a model of the viral gene evolution under human host pressure, we find that synonymous mutations seem driven in the SARS-CoV-2 genome, and particularly in the N ORF, by the viral codon bias, the transition-transversion bias, and the pressure to lower CpG content.
    MeSH term(s) COVID-19/genetics ; CpG Islands ; Evolution, Molecular ; Genome, Viral ; Humans ; RNA, Viral/genetics ; SARS-CoV-2/genetics ; SARS-CoV-2/pathogenicity
    Chemical Substances RNA, Viral
    Language English
    Publishing date 2021-02-08
    Publishing country United States
    Document type Journal Article ; Research Support, N.I.H., Extramural ; Research Support, Non-U.S. Gov't
    ZDB-ID 998579-7
    ISSN 1537-1719 ; 0737-4038
    ISSN (online) 1537-1719
    ISSN 0737-4038
    DOI 10.1093/molbev/msab036
    Database MEDical Literature Analysis and Retrieval System OnLINE

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  6. Article ; Online: Explaining neural activity in human listeners with deep learning via natural language processing of narrative text

    Andrea G. Russo / Assunta Ciarlo / Sara Ponticorvo / Francesco Di Salle / Gioacchino Tedeschi / Fabrizio Esposito

    Scientific Reports, Vol 12, Iss 1, Pp 1-

    2022  Volume 9

    Abstract: Abstract Deep learning (DL) approaches may also inform the analysis of human brain activity. Here, a state-of-art DL tool for natural language processing, the Generative Pre-trained Transformer version 2 (GPT-2), is shown to generate meaningful neural ... ...

    Abstract Abstract Deep learning (DL) approaches may also inform the analysis of human brain activity. Here, a state-of-art DL tool for natural language processing, the Generative Pre-trained Transformer version 2 (GPT-2), is shown to generate meaningful neural encodings in functional MRI during narrative listening. Linguistic features of word unpredictability (surprisal) and contextual importance (saliency) were derived from the GPT-2 applied to the text of a 12-min narrative. Segments of variable duration (from 15 to 90 s) defined the context for the next word, resulting in different sets of neural predictors for functional MRI signals recorded in 27 healthy listeners of the narrative. GPT-2 surprisal, estimating word prediction errors from the artificial network, significantly explained the neural data in superior and middle temporal gyri (bilaterally), in anterior and posterior cingulate cortices, and in the left prefrontal cortex. GPT-2 saliency, weighing the importance of context words, significantly explained the neural data for longer segments in left superior and middle temporal gyri. These results add novel support to the use of DL tools in the search for neural encodings in functional MRI. A DL language model like the GPT-2 may feature useful data about neural processes subserving language comprehension in humans, including next-word context-related prediction.
    Keywords Medicine ; R ; Science ; Q
    Subject code 401
    Language English
    Publishing date 2022-10-01T00:00:00Z
    Publisher Nature Portfolio
    Document type Article ; Online
    Database BASE - Bielefeld Academic Search Engine (life sciences selection)

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  7. Article ; Online: Generative and interpretable machine learning for aptamer design and analysis of in vitro sequence selection.

    Di Gioacchino, Andrea / Procyk, Jonah / Molari, Marco / Schreck, John S / Zhou, Yu / Liu, Yan / Monasson, Rémi / Cocco, Simona / Šulc, Petr

    PLoS computational biology

    2022  Volume 18, Issue 9, Page(s) e1010561

    Abstract: Selection protocols such as SELEX, where molecules are selected over multiple rounds for their ability to bind to a target of interest, are popular methods for obtaining binders for diagnostic and therapeutic purposes. We show that Restricted Boltzmann ... ...

    Abstract Selection protocols such as SELEX, where molecules are selected over multiple rounds for their ability to bind to a target of interest, are popular methods for obtaining binders for diagnostic and therapeutic purposes. We show that Restricted Boltzmann Machines (RBMs), an unsupervised two-layer neural network architecture, can successfully be trained on sequence ensembles from single rounds of SELEX experiments for thrombin aptamers. RBMs assign scores to sequences that can be directly related to their fitnesses estimated through experimental enrichment ratios. Hence, RBMs trained from sequence data at a given round can be used to predict the effects of selection at later rounds. Moreover, the parameters of the trained RBMs are interpretable and identify functional features contributing most to sequence fitness. To exploit the generative capabilities of RBMs, we introduce two different training protocols: one taking into account sequence counts, capable of identifying the few best binders, and another based on unique sequences only, generating more diverse binders. We then use RBMs model to generate novel aptamers with putative disruptive mutations or good binding properties, and validate the generated sequences with gel shift assay experiments. Finally, we compare the RBM's performance with different supervised learning approaches that include random forests and several deep neural network architectures.
    MeSH term(s) Machine Learning ; Neural Networks, Computer ; Thrombin
    Chemical Substances Thrombin (EC 3.4.21.5)
    Language English
    Publishing date 2022-09-29
    Publishing country United States
    Document type Journal Article ; Research Support, Non-U.S. Gov't ; Research Support, U.S. Gov't, Non-P.H.S.
    ZDB-ID 2193340-6
    ISSN 1553-7358 ; 1553-734X
    ISSN (online) 1553-7358
    ISSN 1553-734X
    DOI 10.1371/journal.pcbi.1010561
    Database MEDical Literature Analysis and Retrieval System OnLINE

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  8. Article ; Online: A transfer-learning approach to predict antigen immunogenicity and T-cell receptor specificity

    Barbara Bravi / Andrea Di Gioacchino / Jorge Fernandez-de-Cossio-Diaz / Aleksandra M Walczak / Thierry Mora / Simona Cocco / Rémi Monasson

    eLife, Vol

    2023  Volume 12

    Abstract: Antigen immunogenicity and the specificity of binding of T-cell receptors to antigens are key properties underlying effective immune responses. Here we propose diffRBM, an approach based on transfer learning and Restricted Boltzmann Machines, to build ... ...

    Abstract Antigen immunogenicity and the specificity of binding of T-cell receptors to antigens are key properties underlying effective immune responses. Here we propose diffRBM, an approach based on transfer learning and Restricted Boltzmann Machines, to build sequence-based predictive models of these properties. DiffRBM is designed to learn the distinctive patterns in amino-acid composition that, on the one hand, underlie the antigen’s probability of triggering a response, and on the other hand the T-cell receptor’s ability to bind to a given antigen. We show that the patterns learnt by diffRBM allow us to predict putative contact sites of the antigen-receptor complex. We also discriminate immunogenic and non-immunogenic antigens, antigen-specific and generic receptors, reaching performances that compare favorably to existing sequence-based predictors of antigen immunogenicity and T-cell receptor specificity.
    Keywords machine learning ; immune response ; immunogenicity ; Medicine ; R ; Science ; Q ; Biology (General) ; QH301-705.5
    Subject code 004
    Language English
    Publishing date 2023-09-01T00:00:00Z
    Publisher eLife Sciences Publications Ltd
    Document type Article ; Online
    Database BASE - Bielefeld Academic Search Engine (life sciences selection)

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  9. Article ; Online: Explaining neural activity in human listeners with deep learning via natural language processing of narrative text.

    Russo, Andrea G / Ciarlo, Assunta / Ponticorvo, Sara / Di Salle, Francesco / Tedeschi, Gioacchino / Esposito, Fabrizio

    Scientific reports

    2022  Volume 12, Issue 1, Page(s) 17838

    Abstract: Deep learning (DL) approaches may also inform the analysis of human brain activity. Here, a state-of-art DL tool for natural language processing, the Generative Pre-trained Transformer version 2 (GPT-2), is shown to generate meaningful neural encodings ... ...

    Abstract Deep learning (DL) approaches may also inform the analysis of human brain activity. Here, a state-of-art DL tool for natural language processing, the Generative Pre-trained Transformer version 2 (GPT-2), is shown to generate meaningful neural encodings in functional MRI during narrative listening. Linguistic features of word unpredictability (surprisal) and contextual importance (saliency) were derived from the GPT-2 applied to the text of a 12-min narrative. Segments of variable duration (from 15 to 90 s) defined the context for the next word, resulting in different sets of neural predictors for functional MRI signals recorded in 27 healthy listeners of the narrative. GPT-2 surprisal, estimating word prediction errors from the artificial network, significantly explained the neural data in superior and middle temporal gyri (bilaterally), in anterior and posterior cingulate cortices, and in the left prefrontal cortex. GPT-2 saliency, weighing the importance of context words, significantly explained the neural data for longer segments in left superior and middle temporal gyri. These results add novel support to the use of DL tools in the search for neural encodings in functional MRI. A DL language model like the GPT-2 may feature useful data about neural processes subserving language comprehension in humans, including next-word context-related prediction.
    MeSH term(s) Humans ; Brain Mapping ; Comprehension ; Brain/diagnostic imaging ; Natural Language Processing ; Deep Learning ; Magnetic Resonance Imaging/methods
    Language English
    Publishing date 2022-10-25
    Publishing country England
    Document type Journal Article
    ZDB-ID 2615211-3
    ISSN 2045-2322 ; 2045-2322
    ISSN (online) 2045-2322
    ISSN 2045-2322
    DOI 10.1038/s41598-022-21782-4
    Database MEDical Literature Analysis and Retrieval System OnLINE

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  10. Article ; Online: Assessment of body composition: Intrinsic methodological limitations and statistical pitfalls.

    Barone, Michele / Losurdo, Giuseppe / Iannone, Andrea / Leandro, Gioacchino / Di Leo, Alfredo / Trerotoli, Paolo

    Nutrition (Burbank, Los Angeles County, Calif.)

    2022  Volume 102, Page(s) 111736

    Abstract: Evaluation of body composition (BC) is crucial for an adequate assessment of nutritional status and its alterations, to ensure the optimal tailoring of nutritional therapies during several pathologic conditions. The need for feasible and reliable methods ...

    Abstract Evaluation of body composition (BC) is crucial for an adequate assessment of nutritional status and its alterations, to ensure the optimal tailoring of nutritional therapies during several pathologic conditions. The need for feasible and reliable methods for BC measurement, which could be applied either in healthcare across the lifespan as well as in clinical research and epidemiologic studies, has led to the development of various techniques. Unfortunately, they have not always produced equivalent results due to the fact that they are based on completely different principles or suffer intrinsic biases related to specific conditions. Furthermore, different population and clinical settings (ethnicity, age, type of disease) may interfere, thereby leading to dissimilar results. Finally, the need to compare the data obtained by new techniques to a reference standard has produced a further bias, due to a systematic misinterpretation of the statistical methods in the attempt to correlate the various techniques. In this context, the most used statistical methods for the comparison between different techniques have been Pearson's correlation test, the more recent intraclass correlation coefficient, Lin's concordance correlation coefficient method, and the Bland-Altman analysis. The aim of this review was to offer a summary of the methods that are mostly used in clinical practice to measure BC with the intent to give appropriate suggestions when statistical methods are used to interpret data, and underline pitfalls and limitations.
    MeSH term(s) Absorptiometry, Photon/methods ; Body Composition ; Body Mass Index ; Electric Impedance ; Ethnicity ; Humans ; Nutritional Status
    Language English
    Publishing date 2022-05-14
    Publishing country United States
    Document type Journal Article ; Review
    ZDB-ID 639259-3
    ISSN 1873-1244 ; 0899-9007
    ISSN (online) 1873-1244
    ISSN 0899-9007
    DOI 10.1016/j.nut.2022.111736
    Database MEDical Literature Analysis and Retrieval System OnLINE

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