Inflammatory- and immune responses in relation to bacterial replication in mice following re-infections with Chlamydophila pneumoniae.
OBJECTIVE
Investigation of chronic infections with Chlamydophila pneumoniae.


METHODS
BALB/c mice were repeatedly infected with C. pneumoniae and tested during a 1-year period. Production of histamine, IFN-gamma, IL-6 and antibodies was monitored by ELISA. Live bacteria were cultured and DNA was detected by PCR. Cellular immunity was tested by ELISPOT.


RESULTS
After re-infections, culture positivity and persistence of DNA in lungs and blood were shorter. Detection of DNA at late time points indicated persistent infection in a few mice. Histamine was produced after primary and re-infections, and the level correlated with the number of viable bacteria in lung. IFN-gamma, IL-6 levels, IgG2/IgG1 ratio, IgA titres, and level of chlamydial heat-shock protein antibodies were higher after re-infections. IgM antibodies were demonstrated even after re-infections. High number of IFN-gamma-producing splenocytes was observed after the third inoculation.


CONCLUSIONS
These results promote an understanding of the patho- and immune mechanisms after C. pneumoniae re-infections.
Kis
Z
Z
Division of Virology, National Center for Epidemiology, Budapest, Hungary.
Burian
K
K
Treso
B
B
Acs
K
K
Prohaszka
Z
Z
Fust
G
G
Gonczol
E
E
Endresz
V
V
D000818:Animals; D023521:Chlamydophila Infections / Q000276:immunology* / Q000503:physiopathology; D016993:Chlamydophila pneumoniae / Q000235:genetics / Q000276:immunology* / Q000502:physiology*; D005260:Female; D006632:Histamine / Q000276:immunology; D007371:Interferon-gamma / Q000276:immunology; D015850:Interleukin-6 / Q000276:immunology; D008168:Lung / Q000276:immunology; D051379:Mice; D008807:Mice, Inbred BALB C; D013154:Spleen / Q000276:immunology
D015850:Interleukin-6; D006632:Histamine; D007371:Interferon-gamma