Intravenous Infusion of Autologous Plasma and Buffy Coat Components Enhances Natural Killer Cell Activity: A Case Report

Immune enhancement is increasingly recognized as an important goal not only for patients with chronic illnesses but also for healthy individuals seeking preventive health. Natural killer (NK) cell activity serves as a sensitive biomarker of immune competence, and subclinical deficits may exist even in asymptomatic, otherwise healthy adults. We report a case of a young, female, asymptomatic adult with no underlying disease, in whom markedly decreased NK cell activity was incidentally detected during routine immune function assessment. She had a history of persistent leukopenia, prompting further laboratory testing despite being apparently healthy. No clinical symptoms were present. The patient received intravenous autologous blood therapy, including plasma and buffy coat components, at regular intervals. Serial laboratory monitoring revealed a dramatic and progressive increase in NK cell activity, from a subclinical baseline to well above the normal reference range. Leukocyte and platelet counts remained stable, and no adverse events or subjective symptoms were observed. This case suggests that intravenous autologous blood therapy may enhance NK cell activity in selected individuals with subclinical immune deficits. However, the clinical significance and potential broader applications, including preventive or anti-aging benefits, remain uncertain and require further investigation.