Biochemical aspects of immunomodulation by Propionibacterium acnes

The present paper deals with the effect of indomethacin and/or Propionibacterium acnes (Pa) on the cytochrome P-450 content in liver microsomal fraction, free fatty acids and lipase concentration in serum with respect to the phagocytic activities of monocytomacrophage system, changes in weight of the spleen and liver, survival after LD100 of Klebsiella pneumoniae, and histology of the spleen and liver. The results obtained indicate that INDO acts as an inhibitor of cytochrome P-450 and at the same time stimulates functions of the monocytomacrophage system in all the parameters studied. Pa, a classical immunomodulator, inhibits cytochrome P-450. After the initial suppression phase (3rd day after administration), it stimulates significantly the activity of monocytomacrophage system and increases the amount of FFA in the serum. The combination of both preparations also inhibits the cytochrome P-450 concentration in the liver and stimulates functions of the monocytomacrophage system in all the studied parameters. However, no temporary suppression of phagocytic activities was observed on the 3rd day of the experiment, in contrast to the animals administered Pa alone. Serum FFA concentration increased significantly. The application of both preparations accelerated markedly the onset of proliferation and differentiation processes in lymphatic follicles of the spleen.