Immune regulation in mitochondrial transfer: knowledge structure and emerging trends from a bibliometric perspective

Background: Mitochondrial transfer has emerged as an important form of intercellular communication with growing relevance to immune regulation, inflammation, tissue repair, and tumor immunity. However, the knowledge structure, developmental trajectory, and emerging hotspots of this field remain unclear. Methods: We conducted a bibliometric analysis of studies on mitochondrial transfer and immune regulation published between 2016 and 2025. Publications were retrieved from PubMed, Embase, the Cochrane Library, Scopus, and Web of Science, and analyzed using bibliometrix in R and CiteSpace. Annual publication trends, contributions of countries, institutions, authors, and journals, as well as keyword co-occurrence, clustering, burst detection, and co-citation patterns were evaluated. Results: A total of 967 publications were included. Annual publication output increased steadily, with faster growth after 2020. China and the United States were the leading contributors and occupied central positions in international collaboration networks. Keyword and co-citation analyses showed that early studies mainly focused on mitochondrial DNA-associated inflammatory sensing, innate immunity, and inflammatory injury, whereas recent studies increasingly emphasized intercellular mitochondrial transfer, mitochondrial transplantation, T-cell function, tumor-associated macrophages, cancer immunotherapy, metabolic rewiring, and autophagy-associated mitochondrial quality control. Mitochondrial transplantation and tunneling nanotube were among the most prominent burst terms. Co-citation analysis identified major knowledge domains related to mitochondrial danger signaling, intercellular transfer mechanisms, mesenchymal stem cell-mediated immune regulation, tumor immunity, and translational applications. Conclusion: Bibliometric mapping shows a clear shift from mitochondrial danger signaling toward intercellular transfer and immune-cell metabolic remodeling. Current evidence suggests that immune outcomes are shaped by mitochondrial source, transfer route, recipient-cell state, and disease context. More source-defined and context-specific studies are needed to clarify the therapeutic potential of mitochondrial transfer.