Company: IOBT
Filing Date: 2025-03-31
Form Type: 10-K
Source: 0000950170-25-047744
Chunk: 10

Company: IO Biotech, Inc.
Filing Date: 2025-03-31
Form: 10-K
Item: Item 1
Chunk 10
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 Dendritic cellsBoth termed professional APCs, because of their ability to initiate a T cell response to novel antigens.
    Tumor-associated macrophages (“TAMs”), tolerogenic dendritic cells (“DCs”) and myeloid-derived suppressor cells (“MDSCs”)These are part of the heterogeneous population of APCs that inhibits T cell functions. 

    T cells / T lymphocytesSpecialized white blood cells that recognize and destroy infected or unhealthy cells, such as tumor cells.
    Effector T cellsEffector T cells consists of two main groups: CD4+ T CellsAlso known as helper T cells, CD4+ T cells produce cytokines and help maximize the expansion of the CD8+ T cell population in a primary immune response and facilitate the generation of specific memory CD8+ T cells; and CD8+ T CellsAlso known as cytotoxic T cells, CD8+ T cells kill tumor cells, as well as infected and damaged cells. They express T cell receptors (TCRs), which recognize and bind to specific antigens expressed by cancer cells and infected cells which are presented on the surface of the cells.
    Regulatory T cells (“Tregs”)Tregs suppress activation, proliferation and cytokine production of CD4+ and CD8+ T cells and APCs.

The immune system has the capacity to detect tumor cells and employ a variety of biological mechanisms, or immune effector functions, to specifically target and destroy these cells. However, tumors are adept at undermining the normal immune system functions that allow cancer cells to evade such detection and destruction. 

The Tumor Microenvironment 

Tumors can generate signals that promote tumor growth and suppress immune system functions. The TME is an immunosuppressive environment that surrounds a tumor and includes blood vessels, immune cells, and signaling molecules. A significant portion of the immune reaction against tumors occurs within the TME. There is constant interplay between the TME and the tumor itself, as signals from the tumor can facilitate immunosuppression and tumor growth. In recent years, growing understanding of this interplay has led to the successful development of therapies that modulate specific immunosuppressive mechanisms within the TME to activate the immune system against cancer cells. 

Within the TME, several molecules have been identified that play critical roles in regulating immune functions. These include: 

•PD-1/PD-L1: PD-1 and its ligand, PD-L1, are critical regulators of the immune