Modulation of lymphocyte subpopulations in the small intestine of mice treated with probiotic bacterial strains and infected with Trichinella spiralis.

AIMS

To study the local intestinal lymphocyte immunity in mice with trichinellosis affected by probiotic bacteria.

METHODS AND RESULTS

Enterococcus faecium CCM8558, Enterococcus durans ED26E/7, Limosilactobacillus fermentum CCM7421 and Lactiplantibacillus plantarum 17 L/1 were administered daily (10  CFU ml ) and mice were infected with Trichinella spiralis (400 larvae) on the 7th day of treatment. T. spiralis infection significantly inhibited lymphocyte subpopulations from 5 to 25 days postinfection (dpi). L. fermentum CCM7421 and L. plantarum 17 L/1 restored the CD4 T cell numbers in the epithelium and lamina propria at the control level from 11 dpi. All strains stimulated the CD8 T cells numbers in infected mice, which were restored in the lamina propria on 11 dpi and in the epithelium only on 32 dpi. B cells (CD19 ) inhibition after T. spiralis infection was not affected by treatment till 25 dpi.

CONCLUSIONS

The strain-specific immunomodulatory effect of tested bacteria was confirmed. L. fermentum CCM7421 and L. plantarum 17 L/1 showed the greatest immunomodulatory potential on CD4 and CD8 T lymphocytes in trichinellosis. E. faecium CCM8558 and E. durans ED26E/7 activated only CD8 T cells in the lamina propria.

SIGNIFICANCE AND IMPACT OF THE STUDY

Positive modulation of the gut lymphocyte immunity in T. spiralis infection with bacterial strains showed their beneficial effect with the host's antiparasitic defence.