cik细胞回输=nk细胞和cik细胞的区别

Cytokine-induced killer (CIK) cells and natural killer (NK) cells are both types of immune cells that play a crucial role in the body's defense against cancer and infections. Although they share some similarities in their functions, there are distinct differences between CIK cells and NK cells. In this article, we will explore these differences in terms of their origin, activation, cytotoxicity, specificity, and clinical applications.

1. Origin:

CIK cells are generated from peripheral blood mononuclear cells (PBMCs), which include T cells, while NK cells are derived from lymphoid progenitor cells in the bone marrow. CIK cells are induced to differentiate into effector cells by incubation with cytokines, such as interferon-gamma (IFN-γ) and monoclonal antibodies, whereas NK cells mature in the bone marrow and circulate throughout the body.

CIK cells can be easily expanded in vitro, resulting in a higher number of effector cells for therapeutic purposes. On the other hand, NK cells require complex protocols for expansion, limiting their clinical applications.

2. Activation:

CIK cells are activated by cytokines, such as IFN-γ, interleukin-2 (IL-2), and interleukin-15 (IL-15). These cytokines stimulate the proliferation and cytotoxicity of CIK cells. In contrast, NK cells are activated through a balance of inhibitory and activating signals. The inhibitory signals prevent NK cells from attacking healthy cells, while the activating signals trigger their cytotoxic activity against infected or cancerous cells.

3. Cytotoxicity:

CIK cells exhibit both T cell-like and NK cell-like cytotoxicity. They can directly kill target cells through the release of cytotoxic molecules, such as perforin and granzyme B. Additionally, CIK cells can induce apoptosis in target cells by expressing death ligands, such as Fas ligand (FasL) and tumor necrosis factor-related apoptosis-inducing ligand (TRAIL).

NK cells primarily rely on their cytotoxic activity to eliminate target cells. They release perforin and granzyme B, which induce apoptosis in target cells. Moreover, NK cells can also mediate antibody-dependent cellular cytotoxicity (ADCC) by binding to antibodies attached to target cells.

4. Specificity:

CIK cells have a broad spectrum of target recognition. They can recognize and kill a wide range of tumor cells, regardless of the major histocompatibility complex (MHC) expression. This non-MHC-restricted recognition allows CIK cells to target cancer cells that have downregulated or altered MHC molecules.

In contrast, NK cells exhibit a certain degree of specificity. They can recognize and kill target cells that lack or have reduced expression of MHC class I molecules, a phenomenon known as "missing self-recognition." Additionally, NK cells can also recognize stress-induced ligands on target cells, such as MHC class I chain-related proteins (MICs) and UL16-binding proteins (ULBPs).

5. Clinical Applications:

CIK cell therapy has shown promising results in the treatment of various cancers, including lung cancer, liver cancer, and leukemia. It has been used as an adjuvant therapy after surgery or chemotherapy to eliminate residual cancer cells and prevent relapse. CIK cell therapy has also been explored in the treatment of viral infections, such as hepatitis B and human immunodeficiency virus (HIV).

NK cell therapy has been primarily investigated in the context of hematopoietic stem cell transplantation (HSCT). NK cells can be infused into patients after HSCT to enhance graft-versus-leukemia (GVL) effects and prevent relapse. Additionally, NK cell therapy has shown potential in the treatment of solid tumors, such as ovarian cancer and neuroblastoma.

In conclusion, CIK cells and NK cells are both important components of the immune system with distinct characteristics. CIK cells are derived from T cells and can be easily expanded in vitro, while NK cells originate from lymphoid progenitor cells in the bone marrow. CIK cells are activated by cytokines and exhibit both T cell-like and NK cell-like cytotoxicity. They have a broad spectrum of target recognition, making them suitable for the treatment of various cancers. On the other hand, NK cells rely on a balance of inhibitory and activating signals for activation and exhibit a certain degree of specificity in target recognition. NK cell therapy has been primarily investigated in the context of HSCT and shows potential in the treatment of solid tumors. Both CIK cells and NK cells hold promise for future immunotherapies and warrant further research and clinical development.