From a Drop to Discovery: The Potential of Peripheral Blood for Biomedical Research

Blood samples are dynamic and easily accessible, providing important information about a patient’s health. A blood sample is a minimally invasive tool to study disease mechanisms, monitor response/resistance to therapy, and personalize treatments. Advanced techniques such as next-generation sequencing (NGS), flow cytometry, cytometry by time of flight (CyTOF), and proteomics allow for the comprehensive characterization of the blood-derived components at the DNA, RNA, and protein levels, and assessment of their dynamic changes with treatment. In addition to, for example, tumor markers in cancer patients, circulating tumor cells (CTCs), cell-free DNA (cfDNA), and extracellular vesicles (EVs) are currently important diagnostic, treatment monitoring, and research tools, and can be analyzed through liquid biopsies. Moreover, analysis of immune cells in the blood is important to understand how the peripheral immune system responds to cancer, particularly in the context of immunotherapy, where such analyses can guide therapeutic decisions. By optimizing the use of non-invasive blood samples, clinicians and researchers can improve early detection, refine prognostic models, understand biological mechanisms, and drive personalized treatment approaches.

The scope of this edition is to highlight the potential of peripheral blood as a dynamic and minimally invasive resource for biomedical research. This edition will explore cutting-edge advancements in blood-based diagnostics, biomarker discovery, therapeutic monitoring, personalised treatment, and side effect prediction and management.

Contributions will highlight novel methodologies (e.g. liquid biopsy, single-cell analysis, next-generation sequencing, proteomics, and metabolomics) that expand the enormous possibilities of peripheral blood research, and their clinical applicability. Ethical considerations, standardization challenges (e.g. blood sample collection, processing, and storage), and emerging trends in blood-based research are encouraged and will be key discussion points. This edition is looking for multidisciplinary perspectives from clinical, translational, computational research, and beyond.

The goal of this edition is to position peripheral blood as an “infinite resource” for medical discoveries, reinforcing its role in shaping the future of early diagnostics, monitoring treatment response, and precision medicine with innovative therapeutic approaches.

In this Research Topic, we aim to gather a collection of high-quality original and review articles focusing on how the analysis of the peripheral blood can enhance diagnostic accuracy, predict disease progression, and improve our understanding of immune dynamics. The goal of this edition is to include basic, translational, and clinical research studies that fall into one of these main topics:
1) Liquid biopsies as a non-invasive tool for real-time monitoring of tumor evolution and treatment response;
2) Studies of peripheral immune cell populations, such as T cells, natural killer cells, and monocytes, that can identify immune signatures associated with disease severity and therapy resistance;
3) Blood-based biomarkers, which help stratify patients, personalize treatments, therapy-related side effects, and potentially uncover new therapeutic targets, leading to more precise, patient-centred cancer management.

Topic Editor Inês Pires da Silvar received honoraria speaker fees or advisory roles for Pierre Fabre, Merck Sharpe & Dohme, Roche, Novartis, and Bristol Myers Squibb and has served as consultant on advisory boards for MSD, Regeneron and Strand. Topic Editor Anne Zaremba has received travel support from Novartis, Sanofi Grenzyme, and Bristol-Myers Squibb and has served on advisory boards or received honoraria from MSD. The other Topic Editors declare no competing interests with regard to the Research Topic subject.