Recombinant interleukin-6 protects mice against experimental bacterial infection.
Because of reports of high levels of interleukin-6 (IL-6) in patients during infection, we studied the role of IL-6 in experimental infection. Mice infected with the facultative intracellular pathogen Listeria monocytogenes displayed high levels of IL-6 in their sera and tissues, particularly the spleen, 1 to 3 days after infection. At this time, the IL-6 titers correlated with bacterial numbers in individual mice and in groups of mice given graded doses of Listeria organisms. However, the presence of IL-6 in serum declined after 4 days, even when a large initial dose of bacteria meant that bacterial numbers were still increasing at this time. Recombinant mouse IL-6 injected intraperitoneally before infection protected mice in a dose-dependent manner. It was effective when given 4 h before infection but not when administration was delayed for 24 h postinfection. It is therefore believed that IL-6 plays a role in early priming of the immune response to infection. Its exact function in this model is being investigated.
Liu
Z
Z
Department of Microbiology, University of Melbourne, Parkville, Victoria, Australia.
Simpson
R J
RJ
Cheers
C
C
D000818:Animals; D005260:Female; D015850:Interleukin-6 / Q000096:biosynthesis / Q000627:therapeutic use*; D008088:Listeriosis / Q000378:metabolism / Q000517:prevention & control*; D051379:Mice; D008810:Mice, Inbred C57BL; D011994:Recombinant Proteins / Q000627:therapeutic use
D015850:Interleukin-6; D011994:Recombinant Proteins