* Virally infected cells: This is the primary source of interferons. When a cell becomes infected with a virus, it produces and releases interferons as a defense mechanism.
* Immune cells:
* Natural Killer (NK) cells: These cells kill infected cells and also secrete interferons.
* Macrophages: These cells engulf and destroy pathogens and can also produce interferons.
* Dendritic cells: These cells present antigens to T cells and also contribute to interferon production.
* T cells: Certain types of T cells, like NK T cells, can also produce interferons.
Important Note: Different types of cells produce different types of interferons (alpha, beta, and gamma). For example, most virally infected cells produce interferon-alpha and -beta, while immune cells like NK cells primarily produce interferon-gamma.
