
Coxiella burnetii-Infected NK Cells Release Infectious Bacteria by Degranulation
Author(s) -
Svea Matthiesen,
Luca M. Zaeck,
Kati Franzke,
Rico Jahnke,
Charlie Fricke,
Michael Mauermeir,
Stefan Finke,
Anja Lührmann,
Michael R. Knittler
Publication year - 2020
Publication title -
infection and immunity
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 1.508
H-Index - 220
eISSN - 1070-6313
pISSN - 0019-9567
DOI - 10.1128/iai.00172-20
Subject(s) - coxiella burnetii , biology , microbiology and biotechnology , intracellular parasite , chlamydia psittaci , immune system , rickettsiaceae , degranulation , interleukin 12 , bacteria , q fever , rickettsiales , innate immune system , immunity , virology , chlamydia , immunology , cytotoxic t cell , in vitro , biochemistry , genetics , receptor
Natural killer (NK) cells are critically involved in the early immune response against various intracellular pathogens, including Coxiella burnetii and Chlamydia psittaci Chlamydia -infected NK cells functionally mature, induce cellular immunity, and protect themselves by killing the bacteria in secreted granules. Here, we report that infected NK cells do not allow intracellular multiday growth of Coxiella , as is usually observed in other host cell types. C. burnetii -infected NK cells display maturation and gamma interferon (IFN-γ) secretion, as well as the release of Coxiella -containing lytic granules. Thus, NK cells possess a potent program to restrain and expel different types of invading bacteria via degranulation. Strikingly, though, in contrast to Chlamydia , expulsed Coxiella organisms largely retain their infectivity and, hence, escape the cell-autonomous self-defense mechanism in NK cells.