TY - JOUR
T1 - Radiation- and age-associated changes in peripheral blood dendritic cell populations among aging atomic bomb survivors in Japan
AU - Kajimura, Junko
AU - Lynch, Heather E.
AU - Geyer, Susan
AU - French, Benjamin
AU - Yamaoka, Mika
AU - Shterev, Ivo D.
AU - Sempowski, Gregory D.
AU - Kyoizumi, Seishi
AU - Yoshida, Kengo
AU - Misumi, Munechika
AU - Ohishi, Waka
AU - Hayashi, Tomonori
AU - Nakachi, Kei
AU - Kusunoki, Yoichiro
N1 - Publisher Copyright:
© 2018 by Radiation Research Society.
PY - 2018/1/1
Y1 - 2018/1/1
N2 - Previous immunological studies in atomic bomb survivors have suggested that radiation exposure leads to long-lasting changes, similar to immunological aging observed in T-cell-adaptive immunity. However, to our knowledge, late effects of radiation on dendritic cells (DCs), the key coordinators for activation and differentiation of T cells, have not yet been investigated in humans. In the current study, we hypothesized that numerical and functional decreases would be observed in relationship to radiation dose in circulating conventional DCs (cDCs) and plasmacytoid DCs (pDCs) among 229 Japanese A-bomb survivors. Overall, the evidence did not support this hypothesis, with no overall changes in DCs or functional changes observed with radiation dose. Multivariable regression analysis for radiation dose, age and gender effects revealed that total DC counts as well as subpopulation counts decreased in relationship to increasing age. Further analyses revealed that in women, absolute numbers of pDCs showed significant decreases with radiation dose. A hierarchical clustering analysis of gene expression profiles in DCs after Toll-like receptor stimulation in vitro identified two clusters of participants that differed in age-associated expression levels of genes involved in antigen presentation and cytokine/chemokine production in cDCs. These results suggest that DC counts decrease and expression levels of gene clusters change with age. More than 60 years after radiation exposure, we also observed changes in pDC counts associated with radiation, but only among women.
AB - Previous immunological studies in atomic bomb survivors have suggested that radiation exposure leads to long-lasting changes, similar to immunological aging observed in T-cell-adaptive immunity. However, to our knowledge, late effects of radiation on dendritic cells (DCs), the key coordinators for activation and differentiation of T cells, have not yet been investigated in humans. In the current study, we hypothesized that numerical and functional decreases would be observed in relationship to radiation dose in circulating conventional DCs (cDCs) and plasmacytoid DCs (pDCs) among 229 Japanese A-bomb survivors. Overall, the evidence did not support this hypothesis, with no overall changes in DCs or functional changes observed with radiation dose. Multivariable regression analysis for radiation dose, age and gender effects revealed that total DC counts as well as subpopulation counts decreased in relationship to increasing age. Further analyses revealed that in women, absolute numbers of pDCs showed significant decreases with radiation dose. A hierarchical clustering analysis of gene expression profiles in DCs after Toll-like receptor stimulation in vitro identified two clusters of participants that differed in age-associated expression levels of genes involved in antigen presentation and cytokine/chemokine production in cDCs. These results suggest that DC counts decrease and expression levels of gene clusters change with age. More than 60 years after radiation exposure, we also observed changes in pDC counts associated with radiation, but only among women.
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U2 - 10.1667/RR4854
DO - 10.1667/RR4854
M3 - Article
C2 - 29324175
AN - SCOPUS:85042350001
SN - 0033-7587
VL - 189
SP - 84
EP - 94
JO - Radiation Research
JF - Radiation Research
IS - 1
ER -