Abstract

The immunomodulatory effect of nine strains of Lactobacillus plantarum by stimulation of human peripheral blood mononuclear cells (hPBMCs) from healthy donors was investigated. The production of pro-inflammatory, anti-inflammatory and regulatory cytokines by mononuclear cells following exposure of live bacterial cells was measured using multiplex analysis Luminex. The stimulation and production of cytokine by hPBMCs was evaluated to be strain specific and dependent on the density of cells used for stimulation. A significant increase of IL-6 and IL-1β secretion was demonstrated following stimulation of hPMBCs by high densities of lactobacilli (P < 0.05). By contrast, low density of lactobacilli strains increased the production of TNF-α (P < 0.05) in seven out of nine strains tested. The results have also shown the importance of testing probiotics with using multiplex methods that can help to explain the effectiveness/ineffectiveness of probiotics in the treatment and prevention of gastrointestinal diseases and allergies.

Key words: Lactobacillus plantarum, immunomodulation, cytokine.