Increased interleukin-10 expression is not responsible for failure of T helper 1 immunity to resolve airborne Mycobacterium tuberculosis infection in mice.
With a view to determining whether failure of mice to resolve Mycobacterium tuberculosis (Mtb) infection is a consequence of downregulation of T helper 1 (Th1) immunity by interleukin (IL)-10, mice deleted of the gene for IL-10 were compared with wild-type (WT) mice in terms of their ability to make IL-10 mRNA, generate Th1-mediated immunity [as measured by synthesis of mRNA for interferon-gamma (IFN-gamma)], IL-12p40 and inducible nitric oxide synthase (iNOS), and to control lung infection. It was found that the response of WT mice to infection included a substantial and sustained increase in IL-10 mRNA synthesis in the lungs. A Th1 response in the lungs of WT and IL-10-/- mice was evidenced by a large and sustained increase in the synthesis of mRNA for IFN-gamma, IL-12p40 and iNOS, with somewhat higher levels of these mRNA species being made in the lungs of IL-10-/- mice, particularly at an early stage of infection. However, IL-10-/- mice were no more capable than WT mice at combating infection.
Jung
Yu-Jin
YJ
The Trudeau Institute, Saranac Lake, New York, 12983 USA.
Ryan
Lynn
L
LaCourse
Ronald
R
North
Robert J
RJ
D000818:Animals; D007108:Immune Tolerance; D007371:Interferon-gamma / Q000096:biosynthesis / Q000235:genetics; D016753:Interleukin-10 / Q000235:genetics / Q000276:immunology* / Q000378:metabolism; D018664:Interleukin-12 / Q000096:biosynthesis / Q000235:genetics; D008297:Male; D051379:Mice; D008810:Mice, Inbred C57BL; D019001:Nitric Oxide Synthase / Q000096:biosynthesis / Q000235:genetics; D052247:Nitric Oxide Synthase Type II; D012333:RNA, Messenger / Q000235:genetics; D020133:Reverse Transcriptase Polymerase Chain Reaction; D018417:Th1 Cells / Q000276:immunology*; D014397:Tuberculosis, Pulmonary / Q000276:immunology*
D012333:RNA, Messenger; D016753:Interleukin-10; D018664:Interleukin-12; D007371:Interferon-gamma; D019001:Nitric Oxide Synthase; D052247:Nitric Oxide Synthase Type II; C496317:Nos2 protein, mouse