Related Experiment Video
Updated: May 25, 2026
Activation and Measurement of NLRP3 Inflammasome Activity Using IL-1β in Human Monocyte-derived Dendritic Cells
Published on: May 22, 2014
Effect of influenza A infection on umbilical cord blood natural killer function regulation with interleukin-15
Syh-Jae Lin1, Po-Jen Cheng, Tzou-Yien Lin
1Division of Asthma, Allergy, and Rheumatology, Chang Gung Memorial Hospital, Taoyuan, Taiwan.
Insights
Infant natural killer (NK) cells show reduced responses to influenza A compared to adults. Interleukin-15 (IL-15) may boost NK cell antiviral activity and interferon-gamma production.
Area of Science:
- Immunology
- Virology
- Infectious Diseases
Background:
- Influenza A poses a pandemic threat, with infants exhibiting increased susceptibility to severe infections.
- Natural killer (NK) cells are crucial for innate immunity against viral infections like influenza A.
- Infant NK cell function may be impaired, contributing to their vulnerability to severe influenza.
Purpose of the Study:
- To compare natural killer (NK) cell responses to influenza A between newborns and adults.
- To investigate the role of interleukin-15 (IL-15) in modulating NK cell activity against influenza.
Main Methods:
- Comparison of NK cell responses using umbilical cord blood (UCB) and adult peripheral blood (APB) mononuclear cells.
- Analysis of NK cell apoptosis, surface marker expression (NKp46, CD69, CD107a), perforin expression, and cytotoxicity.
- Assessment of cytokine production (interferon-gamma, tumor necrosis factor-alpha) by NK cells.
Main Results:
- Influenza A induced dose-dependent NK cell apoptosis and NKp46 down-regulation, more significantly in UCB.
- Both UCB and APB NK cells upregulated CD69 and CD107a upon influenza exposure, enhanced by IL-15.
- IL-15 partially restored UCB NK cell perforin expression and K562 cytotoxicity and boosted interferon-gamma and tumor necrosis factor-alpha production.
Conclusions:
- Neonatal and adult NK cells exhibit distinct responses to influenza A.
- IL-15 demonstrates potential therapeutic benefits by enhancing NK cell cytotoxic function and interferon-gamma production against influenza.
Background:
Influenza A is a major pathogen of humans and has the potential to cause worldwide pandemics. Natural killer (NK) cells are important effector cells in the innate immune response against viruses, including influenza A. Infants are more susceptible to severe influenza A viral infection, possibly attributed in part to their defective NK function.
Methods:
We compared the NK responses to influenza using umbilical cord blood (UCB) and adult peripheral blood (APB) mononuclear cells and purified NK cells.
Results:
Influenza A induced dose-dependent apoptosis of NK cells with down-regulation of NKp46 expression, which was more pronounced in UCB. Both UCB and APB NK cells responded to influenza infection by up-regulating CD69 and CD107a expression, a process further enhanced by interleukin (IL) 15. Influenza exposure also down-regulated perforin expression and K562 cytotoxicity in UCB NK cells, which was partially restored by IL-15. The production of interferon (IFN) γ and tumor necrosis factor (TNF) α by NK cells in responding to influenza was further enhanced by IL-15.
Conclusions:
Our findings show differential NK responses between newborns and adults. IL-15 may be beneficial in combating influenza by enhancing cytotoxic function and IFN-γ production.
Related Concept Videos
01:29Immune Response Against Viral Pathogens
NK Cells
NK cells are a crucial part of our innate immune system, acting as the first line of defense against viral infections. These cells can recognize and kill infected cells without prior exposure to the virus, effectively slowing down the spread of infection. Additionally, NK cells produce proinflammatory...
01:27Influenza