Exploration of Immunology

Table 1. Studies investigating the immunological effects of PRF, along with key findings, emerged from these selected publications.

Study	References	Study characteristics	PRF type	Summary of the evidence
1	Sam et al., 2021 [21]	Narrative review	Low-voltage PRF	Modulation of immune activity and synaptic function
2	Vallejo et al., 2013 [22]	Experimental trial	PRF	Pain gene expression modulation
3	Yeh et al., 2015 [23]	Randomized trial	Immediate postoperative PRF administration	Reduction in allodynia via ERK inhibition
4	Cho et al., 2020 [24]	Animal model	Intra-articular PRF	Cartilage protection and pain reduction
5	De la Cruz et al., 2023 [25]	Systematic review	Low-voltage PRF	Neuromodulation mechanisms overview
6	de Moraes Ferreira Jorge et al., 2022 [26]	Review	Orthobiologic PRF	Synergy between PRF and orthobiologics
7	Sluijter et al., 2023 [27]	Exploratory study	PRF	Anti-inflammatory systemic effects
8	Liu et al., 2018 [28]	Controlled trial	DRG PRF	Reduced microglial activity and inflammation
9	Lin et al., 2021 [29]	Clinical evaluation	Lumbar PRF	MAPK activation and inflammatory pain
10	Chen et al., 2024 [30]	Experimental trial	High-voltage PRF	Enhanced autophagy, reduced neuroinflammation
11	Xu et al., 2024 [31]	Experimental trial	High-voltage PRF	GRK2 pathway modulation, reduced depression
12	Xu et al., 2019 [32]	Randomized trial	DRG PRF	Suppressed spinal microglial activity

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PRF: pulsed radiofrequency; ERK: extracellular signal-regulated kinase; DRG: dorsal root ganglia; GRK2: G protein-coupled receptor kinase 2; MAPK: mitogen-activated protein kinase.

Declarations

Acknowledgments

The authors extend their gratitude to the Fondazione Paolo Procacci for its invaluable support, which facilitated constructive discussions and revisions during the preparation of this review.

Author contributions

JM, MLGL: Conceptualization, Investigation, Writing—original draft, Writing—review & editing. RG: Investigation, Writing—original draft, Writing—review & editing. FO, AP, MC: Validation, Writing—review & editing, Supervision. GV: Validation, Writing—review & editing, Supervision, Visualization. All authors read and approved the submitted version.

Conflicts of interest

Giustino Varrassi and Matteo Luigi Giuseppe Leoni, who are the Guest Editors of Exploration of Immunology, had no involvement in the decision-making or the review process of this manuscript. The other authors declare no conflicts of interest.

Ethical approval

Not applicable.

Consent to participate

Not applicable.

Consent to publication

Not applicable.

Availability of data and materials

Not applicable.

Funding

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Copyright

Publisher’s note

Open Exploration maintains a neutral stance on jurisdictional claims in published institutional affiliations and maps. All opinions expressed in this article are the personal views of the author(s) and do not represent the stance of the editorial team or the publisher.

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