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A polypeptide hormone synthesized and secreted by the endodermally derived reticular cells of the thymus gland. Thymosin exerts its actions in several loci: (1) in the thymus gland, either on precursor stem cells derived from fetal liver or from bone marrow, or on immature thymocytes, and (2) in peripheral sites, on either thymic-derived lymphoid cells or on precursor stem cells. The precursor stem cells, which are immunologically incompetent whether in the thymus or in peripheral sites, have been designated as predetermined T cells or T0 cells, and mature through stages termed T1 and T2, each reflecting varying degrees of immunological competence. Thymosin promotes or accelerates the maturation of T0 cells to T1 cells as well as to the final stage of a T2. In addition to this maturation influence, the hormone also increases the number of total lymphoid cells by accelerating the rate of proliferation of both immature and mature lymphocytes. See Immunity

McGraw-Hill Concise Encyclopedia of Bioscience. © 2002 by The McGraw-Hill Companies, Inc.


Any of a group of hormones secreted by the thymus gland that stimulate lymphocyte production within the thymus and confer on lymphocytes elsewhere in the body the capacity to respond to antigenic stimulation.
McGraw-Hill Dictionary of Scientific & Technical Terms, 6E, Copyright © 2003 by The McGraw-Hill Companies, Inc.
References in periodicals archive ?
In this study, we provide an alternative way to produce [N.sup.[alpha]]-terminal acetylated thymosin a1 by cleaving the recombinant protein with legumain, which should be cheaper for large-scale production; as E.
Bae et al., "Thymosin [beta]4 induces the expression of vascular endothelial growth factor (VEGF) in a hypoxia-inducible factor (HIF)-1[alpha]-dependent manner," Biochimica et Biophysica Acta (BBA)--Molecular Cell Research, vol.
White, "Preparation, assay, and partial purification of a thymic lymphocytopoietic factor (thymosin)," Proceedings of the National Academy of Sciences of the United States of America, vol.
RegeneRx is focused on the development of a novel therapeutic peptide, Thymosin beta 4, or TB4, for tissue and organ protection, repair and regeneration.
Wang et al., "MALAT-1, a novel noncoding RNA, and thymosin beta4 predict metastasis and survival in early-stage non-small cell lung cancer," Oncogene, vol.
United States-based RegeneRx Biopharmaceuticals has enrolled the first patients in a phase three clinical trial (ARISE-2 trial) of RGN-259 (Thymosin beta 4), a sterile, preservative-free eye drop formulation developed for patients with dry eye syndrome, neurotrophic keratopathy besides other corneal disorders, it was reported yesterday.
Gurel et al., "Thymosin alpha 1 attenuates lipid peroxidation and improves fructose-induced steatohepatitis in rats," Clinical Biochemistry, vol.
The human thymus produces at least seven thymic proteins: thymopoietin, thymosin alpha, thymulin, thymic humoral factor, hormonal thymic factor, serum thymic factor, and other thymic factors.
Thymosin, containing thymic extracts, augments T-cell function and stimulates the production of interferons and interleukins [46,47].
M2 PHARMA-January 10, 2017-RegeneRx wins notice of acceptance of Australian patent for treatment of neural injury with Thymosin Beta 4
Thymosin [beta]4 (T[beta]4), although first described as a G-actin sequestering peptide regulating cytoskeletal rearrangement and cellular motility [9], has recently been shown to possess additional functions during cell fate determination and angiogenesis.