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Abstract Background: Photobiomodulation (PBM) therapy has demonstrated therapeutic potential in promoting cellular repair, modulating inflammation, and enhancing mitochondrial function. Platelet-rich plasma (PRP) is widely used in regenerative medicine due to its concentration of growth factors and cytokines. Very small embryonic-like stem cells (VSELs), a rare population of pluripotent stem cells present in adult tissues, have emerged as a potential contributor to tissue regeneration. While PBM and PRP are increasingly used in combination, the biological mechanisms underlying their synergistic effects remain incompletely characterized. Objective: This exploratory pilot study aimed to evaluate whether application of the MD Biophysics laser to autologous PRP is associated with measurable changes in VSEL-related antibody marker expression, and to identify directional trends to inform future controlled studies. Methods: PRP samples were collected from participants across seven test dates (July 2024 to February 2025), yielding 18 participant-session datasets. Samples were analyzed before (Pre) and after (Post) laser application using flow cytometry conducted at the UCLA Flow Cytometry Laboratory. Four VSEL-associated antibody markers were assessed: CD45⁻CD34⁺, CXCR4⁺, CD133⁺, and SSEA-4⁺. Analyses were descriptive and focused on paired differences and directional trends due to the exploratory design and absence of a control group. Results: Three of four VSEL-associated markers (CXCR4⁺, CD133⁺, and SSEA-4⁺) demonstrated a group-level increase in median paired differences following laser application. Directional increases were observed in 12/18 sessions for CXCR4⁺, 10/18 for CD133⁺, and 9/18 for SSEA-4⁺. CD45⁻CD34⁺ showed a near-equal distribution of increases and decreases. Ki-67 positivity indicated the presence of viable, proliferative cells. While no findings reached statistical significance due to limited sample size, consistent directional trends were observed across multiple markers. Conclusion: Application of PBM to autologous PRP was associated with directional increases in multiple VSEL-associated antibody markers, suggesting a potential role for stem cell activation or mobilization in the mechanism of action. Although preliminary and not statistically powered, these findings provide hypothesis-generating evidence supporting further investigation. The observed trends informed iterative protocol refinement and establish a foundation for future controlled, adequately powered studies to evaluate clinical efficacy and underlying biological mechanisms.