Neutrophil depletion during Toxoplasma gondii infection leads to impaired immunity and lethal systemic pathology.
The immunomodulatory role of neutrophils during infection with Toxoplasma gondii was investigated. Monoclonal antibody-mediated depletion revealed that neutrophils are essential for survival during the first few days of infection. Moreover, neutrophil depletion was associated with a weaker type 1 immune response as measured by decreased levels of gamma interferon, interleukin-12 (IL-12) and tumor necrosis factor alpha. IL-10 was also decreased in depleted animals. Additionally, splenic populations of CD4(+) T cells, CD8(+) T cells, and NK1.1(+) cells were decreased in depleted mice. Neutrophil-depleted mice exhibited lesions of greater severity in tissues examined and a greater parasite burden as determined by histopathology and reverse transcription-PCR. We conclude that neutrophils are critical near the time of infection because they influence the character of the immune response and control tachyzoite replication.
Bliss
S K
SK
Departments of Microbiology and Immunology, College of Veterinary Medicine, Cornell University, Ithaca, New York 14853-6401, USA.
Gavrilescu
L C
LC
Alcaraz
A
A
Denkers
E Y
EY
D000818:Animals; D002452:Cell Count; D018450:Disease Progression; D005260:Female; D007113:Immunity, Innate / Q000276:immunology; D008221:Lymphoid Tissue / Q000469:parasitology; D051379:Mice; D008810:Mice, Inbred C57BL; D009504:Neutrophils / Q000276:immunology*; D013154:Spleen / Q000166:cytology / Q000276:immunology; D018417:Th1 Cells / Q000276:immunology; D014122:Toxoplasma / Q000276:immunology; D014123:Toxoplasmosis / Q000276:immunology* / Q000469:parasitology