Activated T cells and natural killer (NK) cells are the primary cells that secrete Interferon-gamma (IFN-γ).
Based on the provided reference, IFN-γ plays several crucial roles in the immune system after being secreted by these cell types.
Key Cells Secreting IFN-gamma
According to the reference, the main secretors of IFN-γ are:
- Activated T Cells: These lymphocytes become activated upon encountering specific antigens and differentiate into various subtypes, some of which are potent IFN-γ producers.
- Natural Killer (NK) Cells: These innate lymphoid cells are part of the innate immune system and can recognize and kill target cells without prior sensitization. They are also significant producers of IFN-γ.
| Cell Type | Primary Secretor of IFN-gamma? |
|---|---|
| Activated T Cells | Yes, primarily |
| Natural Killer (NK) Cells | Yes, primarily |
Functions of IFN-gamma
Once secreted by activated T cells and NK cells, IFN-γ performs multiple functions critical for immune responses. The reference highlights several key roles:
- Macrophage Activation: Promoting the activation state of macrophages, enhancing their ability to engulf and destroy pathogens and cellular debris.
- Antiviral and Antibacterial Immunity: Mediating defense mechanisms against viruses and bacteria.
- Antigen Presentation Enhancement: Improving the capacity of cells to present antigens to T cells, thus boosting adaptive immunity.
- Innate Immune System Activation: Orchestrating and coordinating the activation of other components of the innate immune response.
- Lymphocyte–Endothelium Interaction: Regulating how lymphocytes interact with the endothelial cells lining blood vessels, facilitating their movement to sites of inflammation or infection.
- Th1/Th2 Balance Regulation: Influencing the differentiation and activity of T helper cell subsets (Th1 and Th2), which is crucial for determining the type of immune response mounted.
These functions underscore the importance of IFN-γ, secreted by activated T cells and NK cells, in coordinating both innate and adaptive immunity.
