Deficient interferon-alpha response of newborns in comparison to adults.
Human peripheral blood mononuclear cells (PBMC) respond efficiently to viral infections with interferon (IFN)-alpha production. Using Newcastle disease virus (NDV) and Sendai virus as inducers, our experiments with purified mononuclear cell populations of healthy adult volunteers showed that monocytes were the main IFN-alpha producers in these systems. Using an ELISA, which specifically recognized IFN-alpha 2, and a bioassay, in which all subtypes were detected, IFN-alpha 2 was a major subtype expressed. Furthermore, IFN-alpha release was higher after induction with NDV than after stimulation with Sendai virus. To compare the IFN-alpha response of adult PBMC to human cord blood mononuclear cells the cells were stimulated with NDV or Sendai virus. The IFN-alpha response of cord blood mononuclear cells to Sendai virus was slightly reduced compared to that of adult cells. However, IFN-alpha 2 was a major subtype produced. In contrast, when cord blood mononuclear cells were stimulated with NDV the IFN-alpha release was strongly diminished. Furthermore, IFN-alpha 2 was not the major subtype expressed. By in situ hybridization the number of IFN-alpha-producing cells was quantified. We found that 1% of adult PBMC and newborn leukocytes showed detectable IFN-alpha mRNA after stimulation with either Sendai virus or NDV. In conclusion, these data suggest that the ability of cord blood mononuclear cells to produce IFN-alpha is diminished compared to adult PBMC. This impaired IFN-alpha response is not based on a reduced number of IFN-alpha-producing cells, but rather due to underlying control mechanisms of the newborns that are different from the regulation of adult PBMC.
Institute of Immunology and Transfusion Medicine, University of Lübeck Medical School, FRG.
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P
Neustock
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A
Kruse
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S
Bock
B
B
St Pierre
H
H
Kirchner
D000328:Adult; D005312:Fetal Blood / Q000276:immunology; D005786:Gene Expression Regulation / Q000276:immunology*; D006801:Humans; D007231:Infant, Newborn; D016898:Interferon-alpha / Q000172:deficiency*; D009000:Monocytes / Q000276:immunology; D009522:Newcastle disease virus / Q000276:immunology; D010222:Parainfluenza Virus 1, Human / Q000276:immunology; D012333:RNA, Messenger / Q000032:analysis
D016898:Interferon-alpha; D012333:RNA, Messenger