Serum thymosin alpha 1 levels in normal and pathological conditions

ABSTRACT

Introduction: Thymosin alpha 1 (Ta1) is a natural occurring peptide hormone that is crucial for the maintenance of the organism homeostasis. It has been chemically synthesized and used in diseases where the immune system is hindered or malfunctioning.

Areas covered: Many clinical trials investigate the Ta1 effects in patients with cancer, infectious diseases and as a vaccine enhancer. The number of diseases that could benefit from Ta1 treatment is increasing. To date, questions remain about the physiological basal levels of Ta1 and the most effective dose and schedule of treatment. Evidence is growing that diseases characterized by deregulation of immune and/or inflammatory responses are associated with serum levels of Ta1 significantly lower than those of healthy individuals: to date, B hepatitis, psoriatic arthritis, multiple sclerosis and sepsis. The sputum of cystic fibrosis patients contains lower levels of Ta1 than healthy controls. These data are consistent with the role of Ta1 as a regulator of immunity, tolerance and inflammation.

Expert opinion: Low serum Ta1 levels are predictive and/or associated with different pathological conditions. In case of Ta1 treatment, it is crucial to know the patient’s baseline serum Ta1 level to establish effective treatment protocols and monitor their effectiveness over time.

KEYWORDS:

• Serum thymosin a 1
• immune-deficiency
• immune system
• infectious diseases
• cancer
• chronic inflammatory autoimmune diseases

Article highlights

• Thymosin alpha 1 (Ta1) is a naturally occurring 28 aa polypeptide originally isolated from thymus

• Ta1 derives from the N-terminus tract of Prothymosin alpha (ProTa) that is cleaved by legumain, a lysosomal asparagine endopeptidase present in mammals

• ProTa processing to yield Ta1 represents a generalized process in mammals

• Ta1 plays a key role in the control of immunity, tolerance and inflammation

• Physiological levels of Ta1 are crucial for the maintenance of the normal organism homeostasis during the whole life span, even after the thymic involution

• Serum Ta1 levels are measurable, can be predictive of pathology and can be restored by exogenous Ta1 administration

• Monitoring serum Ta1 levels before and during treatments can be helpful in order to develop rational and personalized treatment protocols and increase their therapeutic efficacy.

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Declaration of interest

E. Garaci is a Thymosin patent holder. The authors have no other relevant affiliations or financial involvement with any organization or entity with a financial interest in or financial conflict with the subject matter or materials discussed in the manuscript apart from those disclosed. Peer reviewers on this manuscript have no relevant financial or other relationships to disclose.

Additional information

Funding

This paper has been published as part of a supplement issue covering the proceedings of the Fifth International Symposium on Thymosins in Health and Disease and is funded by SciClone Pharmaceuticals.