Peripheral lymphocyte remodeling following sound-based anxiety intervention: prominent alterations in γδ T-cell subsets.

In the context of the COVID-19 pandemic, closed school management has resulted in college students being more prone to anxiety. As a means of stress reduction, music therapy has been widely used as an adjunctive treatment for anxiety disorders and other psychotic disorders. Some studies have shown that music can influence the immune function, however, there is still a lack of comprehensive research on the effects of the increasingly sophisticated music therapy on the function of the immune system. A healthy immune system and a good mood are closely related; therefore, the purpose of this study was to explore the effects of music therapy on the overall immune system of an anxious population. We recruited 14 anxious college students to participate in music therapy and then analyzed changes in lymphocyte subpopulation phenotypes in their peripheral blood before and after treatment using flow cytometry. Our findings suggest that music therapy not only significantly reduces anxiety scores, but also affects various subpopulations of immune cells in the immune system. First, music therapy increased the frequency of double-positive T cells, CD4+/CD8+ terminally differentiated effector T cells and CD8+CD127- effector T cells in the periphery and down-regulated the frequency of Th1 and Th17 subsets. In addition, music therapy affected the homeostasis of B cell subsets by upregulating the frequencies of marginal zone B cells and memory B cells. Further, we also observed more NKG2D+ NK cells in the periphery of subjects after music therapy. Finally, we found that music treatment significantly reduced the frequency of γδ T cells in the periphery and affected their subpopulation frequency making the ratio of Vδ1+/Vδ2+ γδ T elevated. In addition, the frequency of NKG2D+Vδ1+ γδ T was significantly increased after music therapy. These findings suggest that music therapy is associated with reduced anxiety symptoms accompanied by broad changes in peripheral immune-cell composition.