The effect of bacterial polyamines on the production of the class G immunoglobulins in the culture of mononuclear leukocytes from healthy donors

Abstract

Polyamines synthesized by microorganisms during the metabolism of amino acids have a versatile effect on the innate immune system.  Thus, putrescine and cadaverine are able to inhibit the phagocytic activity of mononuclear leukocytes, and act as a "scavenger" of hydroxyl radicals in the focus of inflammation. However, there is no unambiguous data in the modern literature regarding the effect of polyamines of bacterial origin on the subsystem of adaptive immunity. The aim of the study was to evaluate the effect of cadaverine and putrescine on the production of immunoglobulin G in the culture of mononuclear leukocytes from practically healthy donors. Materials and methods. The object of the study was peripheral venous blood leukocytes from 15 practically healthy donors. Laconose mitogen PWM was used as a B-cell stimulator. Cadaverine and putrescine were used in final concentrations of 5, 25, 50, 75 and 100 mmol/l. At the end of the incubation period, the concentration of immunoglobulins G was determined using the enzyme immunoassay method. Results. A direct relationship was revealed between the concentration of cadaverine and putrescine in the samples and the level of immunoglobulins G (r=0.92 and r=0.98, respectively, p<0.05). Both polyamines had a stimulating effect on IgG production only at concentrations of 75 and 100 mmol/L. Thus, at 75 mmol/l of cadaverine, the level of immunoglobulins was 17.8 IU per 1 mg of protein (p=0.047 for control samples), and at 100 mmol/l - 21.8 IU per 1 mg of protein (p=0.001 for control samples). At a putrescine concentration of 75 mmol/l, the immunoglobulin level was 18.9 IU per 1 mg of protein (p=0.004 for control samples), and at 100 mmol/l - 20.6 IU per 1 mg of protein (p=0.003 for control samples). Conclusion. It was found that the bacterial metabolites putrescine and cadaverine have a stimulating effect on the production of class G immunoglobulins by lymphocytes.