BEGIN:VCALENDAR VERSION:2.0 PRODID:-//132.216.98.100//NONSGML kigkonsult.se iCalcreator 2.20.4// BEGIN:VEVENT UID:20260314T160720EDT-81161JVomk@132.216.98.100 DTSTAMP:20260314T200720Z DESCRIPTION:Integrating large- to high- dimension markers in mechanistic mo dels\n\nMelanie Prague\, Université de Bordeaux\n Tuesday April 14\, 12-1pm \n Zoom Link: https://mcgill.zoom.us/j/87078928687\n In Person: 550 Sherbroo ke\, Room 189\n \n Abstract: Mechanistic models are widely used to describe and explain biological processes over time. However\, they typically rely on a limited number of observable compartments and sparse longitudinal dat a. As a result\, these models are often either too simple to capture compl ex biological phenomena or they face identifiability issues\, particularly when considering interindividual variability in the form of nonlinear mix ed-effects models based on systems of differential equations. In parallel\ , with ongoing technological advances\, longitudinal high-throughput data (e.g.\, -omics\, including transcriptomics and proteomics data) are increa singly available in various contexts and could bring valuable information into mechanistic models to better capture underlying biological processes. However\, integrating such high-dimensional data to inform the dynamics r emains a major challenge\, both mathematically and for broader interpretat ion in public health applications.\n\nIn this talk\, I will present two co mplementary approaches for integrating large- to high-dimensional biomarke rs into mechanistic models. The first approach\, called lasso-SAMBA\, addr esses robust covariate selection in ODE-based non-linear mixed-effect mode ls. It extends the original SAMBA algorithm (which is an iterative model-b uilding algorithm that fastly and sequentially identifies relevant covaria tes on parameters while estimating model using the SAEM algorithm) by repl acing stepwise inclusion with Lasso regression combined with stability sel ection\, ensuring a more reliable identification of relevant covariates wh ile preserving the monotonic decrease of the information criterion. The se cond approach uses observed -omics data to infer the dynamics of unobserve d immune compartments. It relies on an iterative algorithm that alternates between a regularization step\, which identifies the most informative bio markers through penalized likelihood derivatives\, and a mechanistic infer ence step\, where population parameters are estimated using the SAEM algor ithm in Monolix. This framework enables the selection of biomarkers whose temporal patterns best reflect the latent compartments in our model.\n\nTo gether\, these methods provide powerful tools for integrating and selectin g high-dimensional biological data in mechanistic modeling. They will be i llustrated on exemples of immune dynamics after vaccination for Varicella- Zoster virus and immune-viral dynamics after SARS-CoV-2 infection.\n DTSTART:20260414T160000Z DTEND:20260414T170000Z SUMMARY:QLS Seminar Series - Melanie Prague URL:/qls/channels/event/qls-seminar-series-melanie-pra gue-371937 END:VEVENT END:VCALENDAR