Chlamydia pneumoniae infection and inflammation in adults with asthma.
BACKGROUND
Chlamydia pneumoniae infection and immune response to the C. pneumoniae heat shock protein 60 (CpHsp60) have been suggested to be associated with asthma.


OBJECTIVE
To study whether a slightly elevated C-reactive protein (CRP) level as a marker of low-grade systemic inflammation has a role in this association, we collected serum and sputum samples from 103 asthma patients with disease severity ranging from mild to moderate and from 30 healthy volunteers.


METHODS
IgA and IgG antibodies to C. pneumoniae elementary bodies (CpEB) and CpHsp60 were measured by enzyme immunoassay. Serum CRP levels were measured with a rapid two-site ultra-sensitive assay based on time-resolved immunofluorometry.


RESULTS
The asthma patients, especially those with moderate asthma, had higher serum IgA antibody levels to CpHsp60 than the healthy controls (test for trend, p = 0.05), whereas antibody levels to CpEB antigen did not differ between the study groups. CRP levels were higher in both asthma groups compared to the control group and moreover, the patients with moderate asthma had higher CRP levels than those with mild asthma (test for trend, p < 0.01). The subjects with a slightly elevated CRP level, defined as > or =1.8 mg/l, had higher CpEB IgA (p = 0.001), CpEB IgG (p = 0.008) and CpHsp60 IgA (p = 0.023) antibody levels in serum compared to the subjects with lower CRP levels.


CONCLUSIONS
Slightly elevated CRP levels as a marker of low-grade systemic inflammation may be associated with C. pneumoniae infection in asthma patients.
Sävykoski
T
T
Department of Microbiology, National Public Health Institute, University of Oulu, Oulu, Finland.
Harju
T
T
Paldanius
M
M
Kuitunen
H
H
Bloigu
A
A
Wahlström
E
E
Rytilä
P
P
Kinnula
V
V
Saikku
P
P
Leinonen
M
M
D000328:Adult; D001249:Asthma / Q000097:blood / Q000150:complications* / Q000276:immunology; D015415:Biomarkers / Q000032:analysis; D002097:C-Reactive Protein / Q000032:analysis; D018834:Chaperonin 60 / Q000097:blood; D023521:Chlamydophila Infections / Q000097:blood / Q000150:complications* / Q000276:immunology; D016993:Chlamydophila pneumoniae; D005260:Female; D006801:Humans; D007249:Inflammation / Q000150:complications / Q000276:immunology; D008297:Male; D008875:Middle Aged; D018410:Pneumonia, Bacterial / Q000097:blood / Q000150:complications* / Q000276:immunology; D012016:Reference Values; D013183:Sputum / Q000737:chemistry / Q000276:immunology
D015415:Biomarkers; D018834:Chaperonin 60; D002097:C-Reactive Protein