Levels of antibodies to microorganisms implicated in atherosclerosis and of C-reactive protein among atomic bomb survivors.
Although it has been suggested that cardiovascular disease incidence is increased among atomic bomb survivors, the existence of a causal relationship between radiation exposure and atherosclerosis is unclear. Microbial infections, including those caused by Chlamydia pneumoniae, Helicobacter pylori and cytomegalovirus, have recently been implicated in atherosclerosis. Since immune function is somewhat impaired among atomic bomb survivors, their immune defense against such infections might be diminished. To investigate this possibility, we measured antibody levels to the above microorganisms in the sera of survivors. We found that the levels of IgG and IgA antibodies to Chlamydia pneumoniae decreased significantly with radiation dose, whereas the levels of IgG antibodies to Helicobacter pylori or cytomegalovirus remained unchanged. The inflammation marker C-reactive protein was significantly and positively associated with level of antibodies to Chlamydia pneumoniae only in heavily exposed (>or=1000 mGy) survivors. These results may suggest that among atomic bomb survivors, immune response to Chlamydia pneumoniae is diminished and chronic inflammatory reactions related to Chlamydia pneumoniae infection are present.
Hakoda
Masayuki
M
Department of Clinical Studies, Radiation Effects Research Foundation, Hiroshima, Japan. ikashi@cc.hirosaki-u.ac.jp
Kasagi
Fumiyoshi
F
Kusunoki
Yoichiro
Y
Matsuura
Shinsuke
S
Hayashi
Tomonori
T
Kyoizumi
Seishi
S
Akahoshi
Masazumi
M
Suzuki
Gen
G
Kodama
Kazunori
K
Fujiwara
Saeko
S
D000368:Aged; D000907:Antibodies, Bacterial / Q000097:blood* / Q000276:immunology; D000914:Antibodies, Viral / Q000097:blood* / Q000276:immunology; D050197:Atherosclerosis / Q000097:blood* / Q000150:complications / Q000453:epidemiology / Q000276:immunology*; D002097:C-Reactive Protein / Q000378:metabolism*; D023521:Chlamydophila Infections / Q000097:blood / Q000453:epidemiology / Q000276:immunology / Q000382:microbiology; D016993:Chlamydophila pneumoniae / Q000276:immunology / Q000528:radiation effects; D003587:Cytomegalovirus / Q000276:immunology / Q000528:radiation effects; D004307:Dose-Response Relationship, Radiation; D005260:Female; D016480:Helicobacter pylori / Q000276:immunology / Q000528:radiation effects; D006801:Humans; D008297:Male; D009689:Nuclear Warfare; D017741:Survivors; D047789:World War II
D000907:Antibodies, Bacterial; D000914:Antibodies, Viral; D002097:C-Reactive Protein