Related Experiment Video
Updated: May 25, 2026
Two Flow Cytometric Approaches of NKG2D Ligand Surface Detection to Distinguish Stem Cells from Bulk Subpopulations in Acute Myeloid Leukemia
Published on: February 21, 2021
Cervical cancer cell lines expressing NKG2D-ligands are able to down-modulate the NKG2D receptor on NKL cells with
Miriam I Jimenez-Perez1, Luis F Jave-Suarez, Pablo C Ortiz-Lazareno
1Departamento de Fisiología, Centro Universitario de Ciencias de la Salud, Universidad de Guadalajara, Guadalajara, Jalisco, Mexico.
Background:
Cervical cancer represents the third most commonly diagnosed cancer and the fourth leading cause of cancer-related deaths in women worldwide. Natural killer (NK) cells play an important role in the defense against viruses, intracellular bacteria and tumors. NKG2D, an activating receptor on NK cells, recognizes MHC class I chain-related molecules, such as MICA/B and members of the ULBP/RAET1 family. Tumor-derived soluble NKG2D-ligands have been shown to down-modulate the expression of NKG2D on NK cells. In addition to the down-modulation induced by soluble NKG2D-ligands, it has recently been described that persistent cell-cell contact can also down-modulate NKG2D expression. The goal of this study was to determine whether the NKG2D receptor is down-modulated by cell-cell contact with cervical cancer cells and whether this down-modulation might be associated with changes in NK cell activity.
Results:
We demonstrate that NKG2D expressed on NKL cells is down-modulated by direct cell contact with cervical cancer cell lines HeLa, SiHa, and C33A, but not with non-tumorigenic keratinocytes (HaCaT). Moreover, this down-modulation had functional implications. We found expression of NKG2D-ligands in all cervical cancer cell lines, but the patterns of ligand distribution were different in each cell line. Cervical cancer cell lines co-cultured with NKL cells or fresh NK cells induced a marked diminution of NKG2D expression on NKL cells. Additionally, the cytotoxic activity of NKL cells against K562 targets was compromised after co-culture with HeLa and SiHa cells, while co-culture with C33A increased the cytotoxic activity of the NKL cells.
Conclusions:
Our results suggest that differential expression of NKG2D-ligands in cervical cancer cell lines might be associated with the down-modulation of NKG2D, as well as with changes in the cytotoxic activity of NKL cells after cell-cell contact with the tumor cells.
Insights
Cervical cancer cells reduce natural killer (NK) cell NKG2D receptor expression through cell contact. This impacts NK cell activity, with some cancer cells decreasing and others increasing NK cell cytotoxicity.
Area of Science:
- Immunology
- Oncology
Background:
- Cervical cancer is a major global health concern for women.
- Natural killer (NK) cells are crucial in anti-tumor immunity.
- NKG2D is an activating receptor on NK cells that targets tumor cells via ligands like MICA/B and ULBP/RAET1.
Purpose of the Study:
- To investigate if cervical cancer cells down-modulate NKG2D expression on NK cells through cell-cell contact.
- To determine if this down-modulation affects NK cell activity.
Main Methods:
- Co-culture of NK-like cells (NKL) and primary NK cells with cervical cancer cell lines (HeLa, SiHa, C33A) and non-tumorigenic keratinocytes (HaCaT).
- Analysis of NKG2D receptor expression on NK cells post co-culture.
- Assessment of NK cell cytotoxic activity against K562 target cells.
Main Results:
- Direct contact with cervical cancer cell lines, but not HaCaT cells, down-modulated NKG2D on NKL cells.
- All tested cervical cancer cell lines expressed NKG2D-ligands, with varied distribution patterns.
- Co-culture with HeLa and SiHa cells reduced NK cell cytotoxicity, while C33A co-culture enhanced it.
Conclusions:
- Differential NKG2D-ligand expression in cervical cancer cells influences NKG2D down-modulation on NK cells.
- Cell-cell contact with cervical cancer cells alters NK cell cytotoxic function.
- These interactions may play a role in immune evasion by cervical tumors.
Related Concept Videos
01:15Receptor Downregulation in MVBs
The EGFR can initiate signaling pathways that lead to cell proliferation, migration, and differentiation. Overexpression of EGFR stimulates cells to proliferate. Excessive EGFR activation may...
01:27Cytotoxic T Cells-mediated Immune Response
Immunological surveillance is the ability of immune cells to monitor and eliminate infected cells with intracellular pathogens, neoplastically transformed cells, and cells with non-self antigens. Cytotoxic T cells and NK...
01:28Cells of the Innate Immune Response
Phagocytes
Phagocytes police the peripheral tissues by removing cellular debris and responding to the invasion of foreign substances or pathogens. Many phagocytes attack and remove microorganisms even before lymphocytes detect them. The human body has two general...
01:28Chemotherapy-Induced Nausea and Vomiting: Neurokinin-1 Receptor Antagonists
02:38Mitogens and the Cell Cycle
02:34Inhibition of Cdk Activity