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Updated: Aug 9, 2026
Generation of Neural Stem Cells from Discarded Human Fetal Cortical Tissue
Published on: May 25, 2011
Natural killer activity against cultured human neural tumor and fetal brain cells
Abstract:
Ten human neural tumor lines and three established from normal human brain were analyzed for sensitivities to natural killer (NK) cytolysis. Compared to MOLT-4, fetal brain cells were sensitive, but those from adult brain and eight of ten neural tumor cell lines demonstrated marked NK resistance. The frequencies of target-binding cells (TBC) and single-cell lysis of glioma cells bound within tumor cell conjugates demonstrated that the resistance of two lines was explained either by a decrease in the frequencies of TBC or reduced ability of bound NK cells to lyse the tumor cell conjugates. A third resistant line demonstrated decreases in both TBC and tumor cell conjugate lysis. Two glioma lines with less NK resistance had greater frequencies of TBC or conjugate lysis than the resistant lines. Thus, NK resistance can result from decreased recognition of targets, diminished NK lysis of bound targets, or a combination of both.
Insights
Neural tumor cells often resist natural killer (NK) cell attacks. This resistance stems from reduced target recognition, impaired NK cell lysis, or both mechanisms, impacting immune evasion strategies.
Area of Science:
- Immunology
- Neuro-oncology
- Cellular Biology
Background:
- Natural killer (NK) cells are crucial for innate immunity, targeting abnormal cells like tumors.
- Neural tumors exhibit varied responses to NK cell-mediated killing, suggesting underlying resistance mechanisms.
Purpose of the Study:
- To investigate the sensitivity of human neural tumor lines and normal brain cells to NK cell-mediated cytolysis.
- To elucidate the mechanisms contributing to NK cell resistance in neural tumors.
Main Methods:
- Analysis of NK cell sensitivity in ten human neural tumor lines and three normal human brain cell lines.
- Assessment of target-binding cell (TBC) frequencies and single-cell lysis assays for bound tumor cell conjugates.
Main Results:
- Fetal brain cells were sensitive to NK cytolysis, while adult brain cells and eight of ten neural tumor lines showed significant resistance.
- NK resistance in some tumor lines was attributed to decreased TBC frequencies or reduced lysis of bound targets.
- One resistant line exhibited defects in both TBC formation and conjugate lysis, while less resistant lines showed higher TBC frequencies or lysis.
Conclusions:
- Neural tumor resistance to NK cell-mediated killing is multifactorial.
- Mechanisms include impaired target recognition (reduced TBC) and/or diminished cytotoxic function against bound tumor cells.
- Understanding these resistance pathways is vital for developing effective immunotherapies for brain tumors.
