The in vivo immunomodulatory and synergistic anti-tumor activity of thymosin α1-thymopentin fusion peptide and its binding to TLR2

In the present study, the immunomodulatory and synergistic anti-tumor activity of thymosin alpha 1-thymopentin fusion peptide (T alpha 1-TP5) was investigated in vivo. In addition, the potential receptor of T alpha 1-TP5 was investigated by surface plasmon resonance (SPR) binding studies. It was found that T alpha 1-TP5 (305 mu g/kg) alleviated immunosuppression induced by hydrocortisone (HC). T alpha 1-TP5 (305 mu g/kg) combined with cyclophosphamide (CY) had a better tumor growth inhibitory effect than CY alone. Furthermore, T alpha 1-TP5 had a higher affinity (K-D = 6.84 mu mol/L) to toll-like receptor 2 (TLR2) than T alpha 1 (K-D = 35.41 mu mol/L), but its affinity was not significantly different from that of TP5. The results of our present work indicate that T alpha 1-TP5 can possibly be developed as a new immunomodulatory agent. (C) 2013 Elsevier Ireland Ltd. All rights reserved.