Extensive Transformation of Lymphocytes by a Mycoplasma Organism

Abstract

THERE are several agents known to be capable of inducing blast transformation of small lymphocytes. The mitogens phytohaemagglutinin (PHA), concanavalin A (con A) and pokeweed mitogen (PWM) are good examples of such agents¹. The mitogenic activity of these agents is generally considered to be ‘non-specific’ since they transform a high proportion of lymphocytes taken from normal unimmunised animals². In spite of extensive study, the immunological significance of lymphocyte transformation by mitogens is not yet clearly understood. It is possible that blast cells of a similar nature function, in the case of infection, as a defence against intracellular organisms³. It is therefore surprising that only few products from infectious organisms have been reported to induce high lymphocyte transformation. Ling and Husband⁴ transformed lymphocyte with a staphylococcus filtrate and Hirschhorn et at.⁵ obtained a similar effect using streptolysin-S. Recently it has been shown that a heat-stable lipopolysaccharide extract obtained from Escherichia coil will induce a transformation of B lymphocytes in the mouse^{6, 7}.