Search bioRxiv⌕ Search

Biology subjects

Mami-Chouaib, F.

Publications and source records attributed to Mami-Chouaib, F..

2 recordsLinked to original sources

PP-MAPS: dynamic pharmacophore signatures of protein-peptide interfaces from molecular dynamics trajectories

Protein-peptide interactions underlie many cellular signaling and regulatory processes and are increasingly exploited in drug discovery. Characterizing such interfaces often requires the analysis of ensembles of conformations obtained by molecular modeling or molecular dynamics (MD) simulations, where transient contacts and alternative binding modes can be critical. Pharmacophore models provide an intuitive, transferable representation of molecular interactions. Dynophore i.e. "dynamic pharmacophore" approaches have been developed for small-molecule ligands with MD information. We present PP-MAPS (Protein-Peptide Molecular dynamics Assisted Pharmacophore Signatures), an open-source workflow that extracts and aggregates pharmacophore interactions along MD trajectories of protein-peptide complexes. PP-MAPS produces per-residue interaction frequencies and pharmacophore heatmaps that facilitate comparison of peptides, binding sites and receptor variants. PP-MAPS is implemented in Python and is available under an open-source license at https://github.com/camilledepenveiller/PP-MAPS. The workflow relies on GROMACS for trajectory processing and can use either LigandScout or the Chemical Data Processing Toolkit (CDPKit) for pharmacophore feature detection.

bioinformatics↗

Differential predictive value of resident memory CD8+T cell subpopulations in non-small-cell lung cancer patients treated by immunotherapy

A high density of resident memory T cells (TRM) in tumors correlates with improved clinical outcomes in immunotherapy-treated patients. However, in preclinical models, only some subpopulations of TRM are associated with cancer vaccine efficacy. We identified two main TRM subpopulations in tumor-infiltrating lymphocytes derived from non-small cell lung cancer (NSCLC) patients: one co-expressing CD103 and CD49a (DP), and the other expressing only CD49a (MP); both exhibiting additional TRM surface markers like CD69. DP TRM exhibited greater functionality compared to MP TRM. Analysis of T-cell receptor (TCR) repertoire and of the stemness marker TCF-1 revealed shared TCRs between populations, with the MP subset appearing more progenitor-like phenotype. In two NSCLC patient cohorts, only DP TRM predicted PD-1 blockade response. Multivariate analysis, including various biomarkers (CD8, TCF1+CD8+T cells, and PD-L1) associated with responses to anti-PD(L)1, showed that only intra-tumoral infiltration by DP TRM remained significant. This study highlights the non-equivalence of TRM populations and emphasizes the importance of distinguishing between them to better define their role in antitumor immunity and as a biomarker of response to immunotherapy.

immunology↗