Low-density (LD) lipoproteins inhibit phytohaemagglutinin-enhanced turnover of phosphatidylinositol in human peripheral lymphocytes. Turnover was assessed by 32p incorporation into phospholipids and by loss of 32p from [32P]phosphatidylinositol. Inhibition of lipid turnover by LD lipoproteins is not the result of a change in the amount of phytohaemagglutinin required for maximum cellular respon...

Myelin Basic Protein, one of the major membrane protein component of the central nervous system, was used to probe the molecular mechanism of cellular activation by phytohaemagglutinin. Pre-treatment of human lymphocytes with myelin basic protein results in a lower rising of cytosolic concentration of free calcium after stimulation with phytohaemagglutinin. This effect is dependent on myelin ba...

The lectin, phytohaemagglutinin, present in beans survives passage through the gastrointestinal tract in a biologically and immunologically intact form. It is known that by binding to the brush border membranes of the small intestine phytohaemagglutinin induces its hyperplastic growth. However, its effect on the other parts of the gut are not known. This study considered the dose and time depen...

1. Phytohaemagglutinin stimulates the transformation into blast cells of human lymphocytes incubated in vitro. This transformation is accompanied by an increase in the incorporation of [(14)C]leucine into protein and [(3)H]uridine into RNA. 2. The incorporation of [(14)C]leucine by cultures grown in the presence or absence of phytohaemagglutinin is inhibited to the same extent by cycloheximide,...

Pre-treatment of human lymphocytes with 17 beta-estradiol diminishes the increase in concentration of cytosolic free calcium after stimulation with phytohaemagglutinin. The effect is dependent on 17 beta-estradiol concentration and on the preincubation time. The effect is not due to an interaction between 17 beta-estradiol and phytohaemagglutinin, but appears to be a consequence of the binding ...

1. Phytohaemagglutinin induced early changes in the catabolism of glucose by normal human lymphocytes suspended in a bicarbonate buffer. During 4hr. incubation glucose utilization was almost doubled. 2. The rates of several reactions in the metabolism of glucose were estimated. Total pyruvate formation, lactate production and fatty acid synthesis were stimulated to the same degree as was glucos...

To evaluate the effect of storage conditions of blood on the direct relationship between radiation-induced chromosome aberrations and apoptosis in human peripheral blood lymphocytes, whole blood was irradiated with 3Gy X-rays. Directly after irradiation, a sample of blood was analyzed for chromosome damage and proliferation index, after phytohaemagglutinin stimulation and incubation at 37 degre...