Influence of the thymic extract (TP2) on some humoral and cell mediated immunity reactions in normal or irradiated animals.

The authors have studied the action of a thymic extract (TP2) containing thymic polypeptides with a molecular weight under 10,000 daltons, on humoral and cell-mediated immunity reactions in normal animals or in animals immunologically depressed by X-ray irradiation. The following were investigated: serum antibodies, such as antiflagelar agglutinins of TH Salmonella and anti-influenza antibodies in the rat, the plaque-forming hemolytic cells in the mouse spleen, delayed hypersensitivity reaction in guinea-pigs innoculated with BCG, the lymphocyte rosetting reaction in the mouse spleen, and the inhibition of macrophages migration in the rats innoculated with TH Salmonella typhi vaccine. The results showed that TP2 stimulates both the humoral and the cell-mediated immunity reactions and has a radioprotecting effect.

Research on the radioprotecting action of thymic polypeptides and timosterin B.

Administration of the TP2 polypeptidic thymic extract results in normalization of the rosette-forming capacity of the T spleen cells in the X-ray irradiated mouse. The radioprotecting effect was also noticed on the inhibition of macrophages migration in the X-ray irradiated rat inoculated with TH Salmonella typhi vaccine and treated with TP2 or with lipidic extract Timosterin B.

Action of thymic polypeptides of low molecular weight on some immune reactions at tissular and humoral level in guinea-pigs and mice.

Administration of the TP2 extract containing thymic polypeptides of low molecular weight (under 10,000 daltons) was found to stimulate the delayed hypersensitivity reaction in guinea-pigs injected with BCG. It was also found to reduce the hemagglutination titre in mice injected with the APR 8 influenza virus and to raise the antiflagellar agglutinins titre in rats injected with TH Salmonella vaccine. The cellular type of immune reactions was stronger than the humoral one.