Role of tumor necrosis factor alpha in pathogenesis of pneumococcal pneumonia in mice.
The production and role of tumor necrosis factor alpha (TNF-alpha) in pneumococcal pneumonia were investigated in a mouse pneumonia model. When approximately 10(6) CFU of Streptococcus pneumoniae TUM19 were used to inoculate CBA/J mice intranasally, TNF-alpha levels in the lungs and serum began to increase from 1 and 3 days after infection, respectively, concomitantly with the increase in bacterial counts in the lungs. Anti-TNF-alpha antibody accelerated bacterial proliferation in the blood and the death of the mice. Although serum levels of immunoglobulin G antibody against the infecting bacteria were not affected by the anti-TNF-alpha antibody treatment, neutrophil counts in the blood were decreased by the treatment. These results suggest that TNF-alpha produced in the course of pneumococcal pneumonia prevents bacteremia by increasing the number of neutrophils in the blood.
Takashima
K
K
Department of Microbiology, Toho University School of Medicine, Tokyo, Japan. takasima@lab.takeda.co.jp
Tateda
K
K
Matsumoto
T
T
Iizawa
Y
Y
Nakao
M
M
Yamaguchi
K
K
D000818:Animals; D000906:Antibodies / Q000494:pharmacology; D001769:Blood / Q000382:microbiology; D015169:Colony Count, Microbial; D005260:Female; D008168:Lung / Q000382:microbiology; D051379:Mice; D008808:Mice, Inbred CBA; D011018:Pneumonia, Pneumococcal / Q000209:etiology* / Q000401:mortality; D016019:Survival Analysis; D014409:Tumor Necrosis Factor-alpha / Q000276:immunology / Q000378:metabolism*
D000906:Antibodies; D014409:Tumor Necrosis Factor-alpha