Vilon belongs to a class of short bioregulatory peptides developed through Russian gerontology research[4]. In vitro studies demonstrate that the Lys‑Glu dipeptide can modulate lymphocyte populations and cytokine gene expression. Specifically, Vilon has been observed to increase CD5+ cell counts in thymus cell cultures[1] and upregulate interleukin‑2 (IL‑2) mRNA expression in splenocyte preparations[2]. Additional preclinical work suggests effects on TGF‑β1 and vascular permeability in renal models[3]. The pulsed 5‑day monthly regimen is analogized from related short peptide protocols such as Epitalon[5].