Transmission of Toxoplasma gondii from infected dendritic cells to natural killer cells.
The obligate intracellular parasite Toxoplasma gondii can actively infect any nucleated cell type, including cells from the immune system. In the present study, we observed that a large number of natural killer (NK) cells were infected by T. gondii early after intraperitoneal inoculation of parasites into C57BL/6 mice. Interestingly, one mechanism of NK cell infection involved NK cell-mediated targeting of infected dendritic cells (DC). Perforin-dependent killing of infected DC led to active egress of infectious parasites that rapidly infected adjacent effector NK cells. Infected NK cells were not efficiently targeted by other NK cells. These results suggest that rapid transfer of T. gondii from infected DC to effector NK cells may contribute to the parasite's sequestration and shielding from immune recognition shortly after infection.
Persson
Catrine M
CM
Department of Medicine, Center for Infectious Medicine, Karolinska Institutet, F59, Karolinska University Hospital Huddinge, Stockholm, Sweden.
Lambert
Henrik
H
Vutova
Polya P
PP
Dellacasa-Lindberg
Isabel
I
Nederby
Joanna
J
Yagita
Hideo
H
Ljunggren
Hans-Gustaf
HG
Grandien
Alf
A
Barragan
Antonio
A
Chambers
Benedict J
BJ
D000818:Animals; D003713:Dendritic Cells / Q000276:immunology / Q000469:parasitology*; D005434:Flow Cytometry; D006801:Humans; D007694:Killer Cells, Natural / Q000276:immunology / Q000469:parasitology*; D051379:Mice; D008810:Mice, Inbred C57BL; D018613:Microscopy, Confocal; D014122:Toxoplasma / Q000276:immunology; D014123:Toxoplasmosis / Q000276:immunology / Q000635:transmission*