title: Modulation of the peripheral immune system after low-dose radon spa therapy: Detailed longitudinal immune monitoring of patients within the RAD-ON01 study.
abstract: The pain-relieving effects of low-dose radon therapies on patients suffering from chronic painful inflammatory diseases have been described for centuries. Even though it has been suggested that low doses of radiation may attenuate chronic inflammation, the underlying mechanisms remain elusive. Thus, the RAD-ON01 study was initiated to examine the effects of radon spa therapy and its low doses of alpha radiation on the human immune system. In addition to an evaluation of pain parameters, blood was drawn from 100 patients suffering from chronic painful degenerative musculoskeletal diseases before as well as 6, 12, 18, and 30 weeks after the start of therapy. We verified significant long-term pain reduction for the majority of patients which was accompanied by modulations of the peripheral immune cells. Detailed immune monitoring was performed using a multicolor flow cytometry-based whole blood assay. After therapy, the major immune cells were only marginally affected. Nevertheless, a small but long-lasting increase in T cells and monocytes was observed. Moreover, neutrophils, eosinophils and, in particular, dendritic cells were temporarily modulated after therapy. Regarding the immune cell subsets, cytotoxic T and NK cells, in particular, were altered. However, the most prominent effects were identified in a strong reduction of the activation marker CD69 on T, B, and NK cells. Simultaneously, the percentage of HLA-DR+T cells was elevated after therapy. The RAD-ON01 study showed for the first time a modulation of the peripheral immune cells following standard radon spa therapy. These modulations are in line with attenuation of inflammation.
authors.affiliation: a Department of Radiation Oncology , Universitätsklinikum Erlangen, Friedrich-Alexander-Universität Erlangen-Nürnberg , Erlangen , Germany.
authors.forename: Paul F
authors.initials: PF
authors.lastname: Rühle
authors.affiliation: a Department of Radiation Oncology , Universitätsklinikum Erlangen, Friedrich-Alexander-Universität Erlangen-Nürnberg , Erlangen , Germany.|b Research Unit of Radiation Cytogenetics, Helmholtz Center Munich , Neuherberg , Germany.
authors.forename: Roland
authors.initials: R
authors.lastname: Wunderlich
authors.affiliation: a Department of Radiation Oncology , Universitätsklinikum Erlangen, Friedrich-Alexander-Universität Erlangen-Nürnberg , Erlangen , Germany.
authors.forename: Lisa
authors.initials: L
authors.lastname: Deloch
authors.affiliation: c GSI Helmholtzzentrum für Schwerionenforschung , Darmstadt , Germany , and.
authors.forename: Claudia
authors.initials: C
authors.lastname: Fournier
authors.affiliation: c GSI Helmholtzzentrum für Schwerionenforschung , Darmstadt , Germany , and.
authors.forename: Andreas
authors.initials: A
authors.lastname: Maier
authors.affiliation: d Practice for Cardiology , Bad Steben , Germany.
authors.forename: Gerhart
authors.initials: G
authors.lastname: Klein
authors.affiliation: a Department of Radiation Oncology , Universitätsklinikum Erlangen, Friedrich-Alexander-Universität Erlangen-Nürnberg , Erlangen , Germany.
authors.forename: Rainer
authors.initials: R
authors.lastname: Fietkau
authors.affiliation: a Department of Radiation Oncology , Universitätsklinikum Erlangen, Friedrich-Alexander-Universität Erlangen-Nürnberg , Erlangen , Germany.
authors.forename: Udo S
authors.initials: US
authors.lastname: Gaipl
authors.affiliation: a Department of Radiation Oncology , Universitätsklinikum Erlangen, Friedrich-Alexander-Universität Erlangen-Nürnberg , Erlangen , Germany.
authors.forename: Benjamin
authors.initials: B
authors.lastname: Frey
mesh_terms: D000328:Adult; D000368:Aged; D015415:Biomarkers; D059350:Chronic Pain / Q000175:diagnosis / Q000209:etiology / Q000532:radiotherapy; D005260:Female; D006801:Humans; D007107:Immune System / Q000166:cytology / Q000276:immunology / Q000378:metabolism / Q000528:radiation effects*; D056747:Immunomodulation / Q000528:radiation effects*; D008213:Lymphocyte Activation / Q000276:immunology / Q000528:radiation effects; D018655:Lymphocyte Count; D008297:Male; D008875:Middle Aged; D009140:Musculoskeletal Diseases / Q000150:complications / Q000276:immunology; D059408:Pain Management; D011886:Radon / Q000009:adverse effects*; D016176:T-Lymphocyte Subsets / Q000276:immunology / Q000378:metabolism / Q000528:radiation effects
chemical_list: D015415:Biomarkers; D011886:Radon
keywords: Radon spa; attenuation of inflammation; chronic painful musculoskeletal diseases; immune monitoring; immune system