Tumor-associated immune cells (TAICs)

Tumor-associated immune cells (TAICs) comprise a heterogeneous group of leukocytes that infiltrate the tumor microenvironment and significantly influence cancer progression and therapeutic response [1]. These cells include effector populations, such as CD8+ cytotoxic T cells and natural killer cells, which are capable of identifying and destroying malignant cells [2]. Conversely, the environment often contains immunosuppressive populations like regulatory T cells (Tregs), myeloid-derived suppressor cells (MDSCs), and M2-polarized tumor-associated macrophages (TAMs) that facilitate immune evasion [3]. While TAICs are not a single molecular target, they serve as the biological context for various immunotherapies, including checkpoint inhibitors and cell-based therapies [4]. Drugs like pembrolizumab and nivolumab function by blocking inhibitory receptors on these cells to restore their anti-tumor activity [5]. The composition and spatial distribution of TAICs, often referred to as the "Immunoscore," serve as critical prognostic indicators and help predict patient responses to treatment [6]. Consequently, therapeutic strategies often aim to shift the balance of TAICs from a pro-tumorigenic to an anti-tumorigenic state [7].

Other names

Tumor-infiltrating leukocytesTILsTumor-infiltrating immune cellsImmune microenvironmentTumor-associated inflammatory cells

Modulation of the tumor microenvironment through the activation of effector immune cells or the inhibition of immunosuppressive cell populations.