Immune and inflammatory processes occurring within tissues are often undetectable by blood cell counts, standard circulating biomarkers, or imaging, representing an unmet biomedical need. Here, we outline recent advances indicating that liquid biopsies can broadly inform human immune system dynamics. Nucleosome-size fragments of cell-free DNA (cfDNA) released from dying cells into blood contain rich epigenetic information such as methylation, fragmentation, and histone mark patterns. This information allows to infer the cfDNA cell of origin, as well as pre-cell death gene expression patterns. We propose that the analysis of epigenetic features of immune cell-derived cfDNA can shed light on immune cell turnover dynamics in healthy people, and inform the study and diagnosis of cancer, local inflammation, infectious or autoimmune diseases, as well as responses to vaccination.
Bibliographical noteFunding Information:
I.F.F. was supported by a fellowship from the Glassman Hebrew University Diabetes Center and the Foulkes foundation . Y.D. was supported by grants from the Ernest and Bonnie Beutler Research Program of Excellence in Genomic Medicine , JDRF , the BrightFocus Foundation , The Israel Science Foundation , the Waldholtz/Pakula family , the Robert M. and Marilyn Sternberg Family Charitable Foundation , the Helmsley Charitable Trust, and Grail . Y.D. holds the Walter and Greta Stiel Chair and Research grant in Heart studies.
© 2023 Elsevier Ltd
- DNA methylation
- cell-free DNA
- immune cell death
- liquid biopsy