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Biology subjects

Coimbra, N. A. d. R.

Publications and source records attributed to Coimbra, N. A. d. R..

2 recordsLinked to original sources

SeekNSee: A Rule-Based Framework for Prioritizing Proteotypic Peptides

Selecting peptides candidates for target proteomics requires integrating a multicriteria problem, particularly when users lack prior experimental data, programming expertise, or stable access to external repositories. We development SeekNSee, a locally executed R/Shiny application designed to improve the reproducibility and auditability of peptide-candidate screening through enzyme-aware in silico digestion, configurable and traceable rule-level decision tracking. Starting from a user provided reference proteome and target sequences, SeekNSee generates peptides-candidates using nine digestion configurations and evaluates them with 12 rules configured as ignore, apply, or block. Numerical score and retained/blocking status are stored independently, and every candidate-rule outcome is preserved in a rule-level trace. Computational validation confirmed the specified behavior in controlled cases through 198 passing automated assertions, complemented by successful operational and processing tests on Windows and Ubuntu. Proteome-wide application covered all 20,416 reviewed human proteins, generating 733,864 peptide-candidate and 581,026 unique peptides sequences while preserving data integrity, decision traceability, and candidate-specific context. DIA, DDA, and deep-fractionated proteomics benchmarking showed strong associations between SeekNSee scores categories, peptide observation, and multiple analytical measurements. Together, these results support that SeekNSee provides a transparent and traceable screening layer for generating peptide-candidates for subsequent assay and experimental validation.

molecular biology↗

Single-cell proteomics maps circulating monocyte dynamics in advanced head and neck squamous cell carcinoma

It remains unclear whether metastatic progression in head and neck squamous cell carcinoma (HNSCC) is accompanied by functional remodeling of circulating immune cells at the proteome level. To address this question, we applied single-cell proteomics (SCP) to cryopreserved peripheral blood mononuclear cells (PBMCs) from three patients with HNSCC representing distinct stages of metastatic progression and two healthy donors. Proteomic analysis of 619 individual PBMCs resolved major immune cell populations, with up to 1,638 proteins quantified per cell. Trajectory inference, clustering, and differential abundance analyses revealed proteomic remodeling associated with disease progression, with the most pronounced changes occurring within a monocyte cluster composed exclusively of cells from patients with nodal metastasis. This population showed increased abundance of interferon-related proteins, HLA molecules, and myeloid immunoregulatory signatures, consistent with an activated, interferon-associated monocyte state. In parallel, lymphocytes showed reduced coordinated abundance of proteins associated with activation, cytotoxicity, and degranulation, consistent with altered cytotoxic effector programs across disease stages. Overall, these findings reveal distinct proteomic states in circulating monocytes and lymphocytes associated with HNSCC progression and identify selective remodeling of the monocyte compartment in nodal metastatic disease.

cancer biology↗