Most cited article - PubMed ID 3924801
Protective activity of Streptococcus faecalis against pathogenic action of Escherichia coli O55 in gnotobiotic pigs
The concentration of active phagocytes in peripheral blood remained in germfree pigs up to the age of one year approximately at the same level as found at the age of 7 d and did not exceed 0.3 X 10(9)/L of blood, whereas a steady increase was established in conventional pigs. Monoassociation of gnotobiotic piglets with Streptococcus faecalis increased during 24 h the concentration of circulating granulocytes and the concentration of active phagocytes. An even more pronounced effect was obtained when formolized S. faecalis cells were applied intraperitoneally to germfree piglets. This treatment elevated the phagocytosis index also in conventional piglets, as well as in germfree piglets previously given cyclophosphamide. Escherichia coli O 83 or a mixture of anaerobic bacteria did not cause any serious changes in the activity of phagocytosis in gnotobiotic piglets. S. faecalis seems to be a natural factor stimulating both the release of granulocytes from their depots as well as their phagocytic activity.
14-d-old conventional piglets were picked from normal piggery, washed with disinfectants, placed into isolators suitable for germfree work, fed a sterile diet and treated with peroral antibiotics (nalidixic acid, kanamycin, and nystatin). Beginning with day 5 or 7, Enterobacteriaceae were not found in feces. The absence of these bacteria was proved by inoculation of germfree newborn piglets with caecal content. In selectively decontaminated piglets, the white blood cell count in blood had fallen to 6 X 10(9)/L; this decrease was due to an extremely low number of granulocytes (to 0.8 X 10(9)/L). On day 35, IgG-positive cells almost disappeared from the spleen, whereas IgA cells were found in an unusually great amount. Corresponding changes in serum levels were established. The colonization resistance effect in Enterobacteriaceae-deprived piglets was confirmed; settling of introduced various E. coli strains did not occur or was delayed.
- MeSH
- Germ-Free Life * MeSH
- Immunoglobulin A, Secretory analysis MeSH
- Leukocyte Count MeSH
- Swine immunology microbiology MeSH
- Spleen immunology MeSH
- Digestive System microbiology MeSH
- Animals MeSH
- Check Tag
- Animals MeSH
- Publication type
- Journal Article MeSH
- Names of Substances
- Immunoglobulin A, Secretory MeSH