Thymosin α1 application augments immune response and down-regulates tumor weight and organ colonization in BALB/c-mice

The immunomodulatory and antimetastatic/antitumor activity of thymosin alpha (1) (T alpha (1)) was evaluated in BALB/c-mice. Daily subcutaneous application (7 consecutive days. 0.01-10 mug of T alpha (1)/injection per mouse) upregulated the number of thymocytes and peripheral blood cells in tumor bearing mice. To check the influence of T alpha (1) treatment on growth of experimental metastases. RAW H10 lymphosarcoma cells or L-1 sarcoma cells were intravenously injected into BALB/c-mice to establish liver or lung metastases. Local tumor growth was induced by subcutaneous injection of L-1 sarcoma cells. T alpha (1) was subcutaneously administered daily for 7 consecutive days starting 24 h after tumor cell challenge. Organ colonization. as well as local tumor growth, were investigated on day 14 after tumor cell inoculation, and demonstrated a statistically significant (P < 0.05 reduction of experimental liver and lung metastases and local tumor growth for T<alpha>(1) treated mice. (C) 2000 Elsevier Science Ireland Ltd. All rights reserved.