Human thymic hormones increase in vitro IL-4 production in atopic patients

There is little information about the relationship between thymic hormones and atopy.

Human thymostimulin was obtained from thymus of children who died in car crashes. These polypeptides were purified by a Sephadex G-50 column fractionation and incubated in vitro with human lymphocytes obtained from atopic and non-atopic subjects of different ages. The SDS-PAGE revealed at least the presence of three broad bands of proteins with 20, 30 and 60 kDa of molecular weight approximately. Levels of IL-4 from lymphocytic cultures were measured by ELISA and correlated with atopic and non-atopic status and with age. The non-atopic controls showed 5.20 UI/ml +/- 1.14 UI/ml of IL-4 meanwhile the non-atopic cells stimulated showed 8.15 UI/ml +/- 2.438 UI/ml. On the other hand, the atopic cells revealed a spontaneous release of 12 +/- 1.812 UI/ml meanwhile those stimulated by the thymostimulin showed 18.53 UI/ml +/- 1.40 UI/ml.

Thymic polypeptides were able to increase the levels of IL-4 in both groups although the atopic subjects showed the greater increase (p > 0.001) independently of their age.

As it has been suggested that these hormones could be used therapeutically in atopic subjects, our results warn about the adverse effects that could be produced with them.