Related Experiment Videos
Newcastle disease virus-induced functional impairments and biochemical changes in chicken heterophils
K M Lam1, M B Kabbur, J P Eiserich
1Department of Population Health and Reproduction, University of California, Davis 95616, USA. klam@ucdavis.edu
Abstract:
The GB strain of Newcastle disease virus (NDV) is used to infect chicken heterophils in vitro. Heterophils have a decreased ability to phagocytize bacteria 3 h after infection, and those that did engulfed fewer bacteria relative to non-infected heterophils. Infected heterophils have a decreased H2O2 production as shown by flow cytometry, but an increased nitric oxide production, suggesting that NDV can stimulate heterophils to produce and/or utilize nitrogen intermediates but not oxygen intermediates. DNA extracted from the infected heterophils shows a marked fragmentation, suggesting that NDV infection may cause heterophils to undergo apoptosis.
Insights
Newcastle disease virus (NDV) infection impairs chicken heterophil functions, reducing bacterial phagocytosis and promoting DNA fragmentation. This suggests NDV may induce apoptosis in these immune cells.
Area of Science:
- * Avian immunology
- * Virology
- * Cellular microbiology
Background:
- * Newcastle disease virus (NDV) is a significant pathogen affecting poultry worldwide.
- * Chicken heterophils are crucial innate immune cells involved in combating bacterial infections.
- * The impact of NDV infection on heterophil function remains incompletely understood.
Purpose of the Study:
- * To investigate the in vitro effects of the GB strain of NDV on chicken heterophil functions.
- * To assess changes in phagocytic activity, reactive oxygen species (ROS), and nitric oxide (NO) production.
- * To evaluate potential NDV-induced apoptosis in heterophils.
Main Methods:
- * Infection of chicken heterophils with the GB strain of NDV in vitro.
- * Assessment of bacterial phagocytosis via quantitative analysis.
- * Flow cytometry used to measure hydrogen peroxide (H2O2) and nitric oxide (NO) production.
- * DNA fragmentation analysis to detect apoptosis.
Main Results:
- * NDV-infected heterophils exhibited significantly reduced bacterial phagocytosis 3 hours post-infection.
- * A decrease in hydrogen peroxide (H2O2) production was observed, while nitric oxide (NO) production increased.
- * Marked DNA fragmentation was evident in NDV-infected heterophils, indicative of apoptosis.
Conclusions:
- * NDV infection impairs critical functions of chicken heterophils, including phagocytosis.
- * NDV modulates heterophil's oxidative and nitrogen intermediate metabolism, favoring NO over O2 intermediates.
- * The observed DNA fragmentation suggests that NDV infection can induce apoptosis in chicken heterophils.