Thymopentin
Immune & Anti-InflammatoryAlso known as: TP-5, Timunox, Arg-Lys-Asp-Val-Tyr, Thymopoietin 32-36, Thymopentin Injection
Mechanism
Thymopentin is a synthetic five-amino-acid fragment of thymopoietin, a natural hormone produced by the thymus gland that directs T-cell development. It contains the minimal active sequence needed to drive immature T-cells to become mature, functional immune soldiers. It has been used clinically for immune deficiency, autoimmune conditions (rheumatoid arthritis, lupus), chronic hepatitis B, and as an adjunct to cancer chemotherapy to restore immune function. It represents a more targeted approach than crude thymus extracts.
Technical detail
Thymopentin (Arg-Lys-Asp-Val-Tyr) corresponds to residues 32-36 of thymopoietin, the minimal active sequence retaining full biological activity of the 49-residue parent protein. Binds to specific receptors on T-cell precursors and immature thymocytes, inducing: (1) differentiation of pre-T cells — upregulates CD2, CD3, CD4, and CD8 surface markers; (2) modulation of intracellular cAMP and calcium flux in lymphocytes; (3) increased IL-2 production and IL-2 receptor (CD25) expression; (4) enhanced NK cell activity and macrophage function; (5) normalization of CD4/CD8 ratios in immunocompromised patients. Does not stimulate antibody production directly but enhances T-helper function that supports B-cell responses. Clinical studies: improved immune parameters in primary immunodeficiency, HIV (early), rheumatoid arthritis, and chronic hepatitis B. Half-life ~30 seconds IV, but biological effects persist for days due to T-cell commitment events.
Evidence
- moderate
Friedmann N. (1985) — Surv Immunol Res. — PMID: 3898287
Safety review covering preclinical testing and treated patients across multiple conditions found side-effect rates similar to placebo and reported tolerability even with longer courses and concomitant medications.