Identity
unlike the synthetic single peptides elsewhere in this register, Thymalin is a polypeptide complex extracted from the thymus of young calves (by mild acid extraction) and standardized as a pharmaceutical. The thymus is the organ that "educates" T-lymphocytes; Thymalin is positioned as a thymic immune-restorative / immunocorrector. It's the prototype of the "peptide bioregulator" concept — the idea that short peptides act as precise regulators of gene expression in specific tissues rather than as blunt pharmacological agents.
Mechanism (as proposed)
Thymalin's activity is attributed to its short peptides — KE (Lys-Glu), EW (Glu-Trp), EDP (Glu-Asp-Pro) — which are proposed to bind directly to double-stranded DNA and/or histone proteins and thereby regulate gene expression: the synthesis of immune-system proteins, cytokines, heat-shock proteins, "gerontogenes," and the differentiation/proliferation of stem and immune cells (while reducing apoptosis). Functionally, the pitch is restoring the aging thymus's T-cell output and thus pushing back on immunosenescence — and, in the geroprotection framing, "normalizing" cardiovascular/endocrine/immune/nervous-system indices. This "short peptides as epigenetic gene-expression regulators" model is the theoretical heart of the entire bioregulator school. It is mechanistically coherent and supported by the group's own molecular work, but — like the clinical claims — not broadly validated by independent labs.