Modelling the Innate Immune Response against Avian Influenza Virus in Chicken.

Area of Science:

• * Virology
• * Immunology
• * Mathematical Biology

Background:

• * Limited understanding of the host immune response to avian influenza virus (AIV) in poultry.
• * Innate immune responses are critical for controlling viral infections.
• * Chicken lung immunity dynamics require further elucidation.

Purpose of the Study:

• * To develop a mathematical model of the innate immune response to AIV in chicken lungs.
• * To describe the dynamics of viral load, interferons (IFN-α, -β, -γ), pulmonary cells, and Natural Killer (NK) cells.
• * To validate model predictions using experimental data from infected chickens.

Main Methods:

• * Development of a mathematical model simulating AIV infection dynamics in chicken lungs.
• * Incorporating viral load, immune mediators (interferons), host cells, and NK cell activity.
• * Validation against experimental data on viral load and NK cell degranulation.

Main Results:

• * Model accurately predicts initial exponential viral load increase, consistent with experimental data.
• * Duration to reach a specific viral load correlates linearly with inoculation dose.
• * Viral load decline is attributed to both target-cell limitation and innate immune response.
• * Target-cell limitation alone cannot explain viral load patterns observed in chicken lungs.
• * Model qualitatively matches experimental viral load data up to 4 days post-infection.
• * Discrepancies noted in Natural Killer cell degranulation predictions early in infection.

Conclusions:

• * The innate immune response plays a significant role in controlling AIV replication in chicken lungs.
• * Mathematical modeling provides valuable insights into host-pathogen dynamics during avian influenza.
• * Further refinement of models is needed to fully capture NK cell responses and early infection dynamics.