Why does the immune system sometimes fail to eradicate established tumors, despite exhibiting an initial anti-tumor response?

💡 Explanation

Tumor-induced T-cell tolerance develops because tumors can express ligands that engage inhibitory receptors on T cells, leading to T-cell exhaustion or anergy. Therefore, the immune system can fail to eliminate the tumor, rather than being due to initial high cytotoxicity or increased MHC expression which would promote tumor cell destruction.

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