title: Levels of antibodies to microorganisms implicated in atherosclerosis and of C-reactive protein among atomic bomb survivors.
abstract: 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.
authors.affiliation: Department of Clinical Studies, Radiation Effects Research Foundation, Hiroshima, Japan. ikashi@cc.hirosaki-u.ac.jp
authors.forename: Masayuki
authors.initials: M
authors.lastname: Hakoda
authors.forename: Fumiyoshi
authors.initials: F
authors.lastname: Kasagi
authors.forename: Yoichiro
authors.initials: Y
authors.lastname: Kusunoki
authors.forename: Shinsuke
authors.initials: S
authors.lastname: Matsuura
authors.forename: Tomonori
authors.initials: T
authors.lastname: Hayashi
authors.forename: Seishi
authors.initials: S
authors.lastname: Kyoizumi
authors.forename: Masazumi
authors.initials: M
authors.lastname: Akahoshi
authors.forename: Gen
authors.initials: G
authors.lastname: Suzuki
authors.forename: Kazunori
authors.initials: K
authors.lastname: Kodama
authors.forename: Saeko
authors.initials: S
authors.lastname: Fujiwara
mesh_terms: 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
chemical_list: D000907:Antibodies, Bacterial; D000914:Antibodies, Viral; D002097:C-Reactive Protein