[Soluble regulators produced by the lymphocytes].

Data are given on lymphokins, the biologically active substances lymphocytes when the latter are stimulated with specific antigens or unspecific mitogens. Discussed are their essence, antigen specificity, cell origin, and the methods of purification, standardization, and evaluation of biologic importance. It is believed that the lymphokins appear to be the products of primary activation of T lymphocytes.

[Effect of physical and chemical factors on the antigenic activity of the cell walls of Brucella abortus 99].

Studied was the effect of some physical and chemical factors--heating, acidity, treatment with ultraviolet rays, and enzyme treatment--on the activity of the Brucella abortus 99 cell wall antigen. The activity of the antigen was determined through the microreaction of complement-fixing after Kolmer. It was found that the antigen was most sensitive to acid treatment and treatment with ultraviolet rays, and was more slightly sensitive to the effect of alkaline agents and pronase.

[Chemical and immunologic study of the bacterial wall of Brucella abortus 99].

The investigations were carried out through the CFT serologic activity of some of the Brucella abortus 99 cell components. It was found that only 0.6 per cent of the weight of the bacterial walls could be extracted by means of physiologic saline.

[Determination of biologically active protein fractions and their polypeptide chains in pseudoplague virus (NDV)].

The protein fractions of the intact Newcastle disease virus as well as those of a disintegrated NDV (treatment with tween 80, ether and triton times 100) were separated through electrophoresis on polyacrylamid gel. Determined were the biologic activity, molecular weight and number of polypeptid chains of each fraction. It was found that 5 of the fractions obtained are composed of aggregates of 3 polypeptid chains, and 2 of the fractions represent single polypeptide chains.