Plant Exosome Injections for Hair Follicle Proliferation and Immune Modulation: An Immunohistochemical Study.

BACKGROUND

Plant-derived exosomes have demonstrated clinical efficacy in hair restoration, yet the cellular and molecular mechanisms underlying their effects in the human scalp remain poorly defined. This study investigates follicular proliferation, stem cell activation, and local immune modulation following intradermal injections of plant-based exosomes in adults with early-stage alopecia.

METHODS

Thirty participants received intradermal plant-derived exosome injections. Punch biopsies of 3.5 mm were collected at baseline and 6 months and processed in both vertical and horizontal orientations. Immunohistochemistry was performed for β-catenin to assess Wnt signaling, CD34 for stem cell populations, and CD68, CD3, CD20, and CD138 for immune cell profiling. Quantitative evaluation measured follicular cellular activity and immune cell distribution across multiple follicular units.

RESULTS

Posttreatment biopsies demonstrated significantly increased β-catenin expression within the follicular epithelium, indicating activation of Wnt-mediated regenerative pathways. CD34-positive stem cells surrounding follicles were markedly enhanced, suggesting recruitment of progenitor populations. Immune profiling revealed a significant reduction in CD68-positive macrophages and CD3positive T cells, whereas B cells and plasma-cell populations remained stable, confirming the anti-inflammatory effect of plant-derived exosomes. These cellular changes were accompanied by qualitative clinical improvement observed on standardized photography and dermoscopic evaluation.

CONCLUSIONS

Plant-based exosome injections were associated with increased stem cell activity, activation of Wnt signaling, and modulation of the local immune environment, providing mechanistic insight into hair follicle regeneration. The findings highlight the cellular and molecular basis for botanical exosome therapy and support further investigation as a novel regenerative approach for human hair restoration.