Effects of Azospirillum brasilense Sp7 lectin and Phaseolus vulgarus phytohemagglutinin on cytokine activity of lymphocytes in vitro.

We studied the effect of fucose-specific lectin from Azospirillum brasilense Sp7 bacteria and Phaseolus vulgarus phytohemagglutinin (PHA) on activity of IFN-γ, IFN-α, IL-1α, IL-4, IL-8, and TNF-α in human blood in vitro. During the experiment, IFN-γ production increased from 25 pg/ml in controls to 103 and 56 pg/ml under the influence of lectin and PHA, respectively. Agglutinins had similar effects on IFN-α production. Bacterial lectin increased IL-1α level from 2.65±0.08 to 8.45±0.41 pg/ml. PHA also increased IL-1α levels, but this effect was by 1.5-2 times less pronounced. Bacterial lectin and PHA increased production IL-4 by almost 2 times and production of IL-8 by 6 and 5 times, respectively, compared to the control. No differences were found in the effects of bacterial lectin and PHA on TNF-α synthesis. Experiments showed that immunostimulatory and immunomodulatory effects of bacterial lectin are more pronounced than those of PHA.