PMID- 19426498
OWN - NLM
STAT- MEDLINE
DCOM- 20090709
LR  - 20211020
IS  - 1471-2172 (Electronic)
IS  - 1471-2172 (Linking)
VI  - 10
DP  - 2009 May 8
TI  - Antibody-mediated immunity to the obligate intracellular bacterial pathogen 
      Coxiella burnetii is Fc receptor- and complement-independent.
PG  - 26
LID - 10.1186/1471-2172-10-26 [doi]
AB  - BACKGROUND: The obligate intracellular bacterial pathogen Coxiella burnetii 
      causes the zoonosis Q fever. The intracellular niche of C. burnetii has led to 
      the assumption that cell-mediated immunity is the most important immune component 
      for protection against this pathogen. However, passive immunization with immune 
      serum can protect naive animals from challenge with virulent C. burnetii, 
      indicating a role for antibody (Ab) in protection. The mechanism of this 
      Ab-mediated protection is unknown. Therefore, we conducted a study to determine 
      whether Fc receptors (FcR) or complement contribute to Ab-mediated immunity (AMI) 
      to C. burnetii. RESULTS: Virulent C. burnetii infects and replicates within human 
      dendritic cells (DC) without inducing their maturation or activation. We 
      investigated the effects of Ab opsonized C. burnetii on human monocyte-derived 
      and murine bone marrow-derived DC. Infection of DC with Ab-opsonized C. burnetii 
      resulted in increased expression of maturation markers and inflammatory cytokine 
      production. Bacteria that had been incubated with naive serum had minimal effect 
      on DC, similar to virulent C. burnetii alone. The effect of Ab opsonized C. 
      burnetii on DC was FcR dependent as evidenced by a reduced response of DC from 
      FcR knockout (FcR k/o) compared to C57Bl/6 (B6) mice. To address the potential 
      role of FcR in Ab-mediated protection in vivo, we compared the response of 
      passively immunized FcR k/o mice to the B6 controls. Interestingly, we found that 
      FcR are not essential for AMI to C. burnetii in vivo. We subsequently examined 
      the role of complement in AMI by passively immunizing and challenging several 
      different strains of complement-deficient mice and found that AMI to C. burnetii 
      is also complement-independent. CONCLUSION: Despite our data showing 
      FcR-dependent stimulation of DC in vitro, Ab-mediated immunity to C. burnetii in 
      vivo is FcR-independent. We also found that passive immunity to this pathogen is 
      independent of complement.
FAU - Shannon, Jeffrey G
AU  - Shannon JG
AD  - Coxiella Pathogenesis Section, Laboratory of Intracellular Parasites, Rocky 
      Mountain Laboratories, National Institute of Allergy and Infectious Diseases, 
      National Institutes of Health, Hamilton, Montana, USA. jshannon@niaid.nih.gov
FAU - Cockrell, Diane C
AU  - Cockrell DC
FAU - Takahashi, Kazue
AU  - Takahashi K
FAU - Stahl, Gregory L
AU  - Stahl GL
FAU - Heinzen, Robert A
AU  - Heinzen RA
LA  - eng
GR  - R01 HL052886/HL/NHLBI NIH HHS/United States
GR  - P01 AI052343/AI/NIAID NIH HHS/United States
GR  - P50 DE016191/DE/NIDCR NIH HHS/United States
GR  - DE016191/DE/NIDCR NIH HHS/United States
GR  - HL52886/HL/NHLBI NIH HHS/United States
GR  - ImNIH/Intramural NIH HHS/United States
GR  - HL56068/HL/NHLBI NIH HHS/United States
GR  - DE017821/DE/NIDCR NIH HHS/United States
GR  - AI052343/AI/NIAID NIH HHS/United States
GR  - R01 DE017821/DE/NIDCR NIH HHS/United States
PT  - Journal Article
PT  - Research Support, N.I.H., Extramural
PT  - Research Support, N.I.H., Intramural
DEP - 20090508
PL  - England
TA  - BMC Immunol
JT  - BMC immunology
JID - 100966980
RN  - 0 (Antigen-Antibody Complex)
RN  - 0 (Antigens, Bacterial)
RN  - 0 (Immunoglobulin G)
RN  - 0 (Receptors, Fc)
RN  - 9007-36-7 (Complement System Proteins)
SB  - IM
MH  - Animals
MH  - Antibody-Dependent Cell Cytotoxicity
MH  - Antigen-Antibody Complex/immunology/metabolism
MH  - Antigens, Bacterial/immunology
MH  - Cell Differentiation/genetics/immunology
MH  - Complement Activation/genetics/immunology
MH  - Complement System Proteins/genetics/*metabolism
MH  - Coxiella burnetii/*immunology
MH  - Dendritic Cells/immunology/*metabolism/microbiology/pathology
MH  - Immunization, Passive
MH  - Immunoglobulin G/*metabolism
MH  - Mice
MH  - Mice, Inbred C57BL
MH  - Mice, Knockout
MH  - Q Fever/immunology
MH  - Receptors, Fc/genetics/*metabolism
PMC - PMC2689861
EDAT- 2009/05/12 09:00
MHDA- 2009/07/10 09:00
PMCR- 2009/05/08
CRDT- 2009/05/12 09:00
PHST- 2008/11/28 00:00 [received]
PHST- 2009/05/08 00:00 [accepted]
PHST- 2009/05/12 09:00 [entrez]
PHST- 2009/05/12 09:00 [pubmed]
PHST- 2009/07/10 09:00 [medline]
PHST- 2009/05/08 00:00 [pmc-release]
AID - 1471-2172-10-26 [pii]
AID - 10.1186/1471-2172-10-26 [doi]
PST - epublish
SO  - BMC Immunol. 2009 May 8;10:26. doi: 10.1186/1471-2172-10-26.