Immunoengineering can overcome the glycocalyx armor of cancer cells. The glycocalyx, a protective layer on cancer cells, shields them from immune attack by modulating interactions with cytotoxic immune cells like NK and T cells. This study shows that the thickness of the glycocalyx, regulated by mucin expression and glycosylation, significantly affects immune cell-mediated cytotoxicity. Mucins, particularly Muc1, form a thick, brush-like layer that protects cancer cells from immune recognition. The thickness of this layer can be altered by modifying mucin expression or glycosylation, which in turn affects immune cell interactions. Using advanced techniques like Scanning Angle Interference Microscopy (SAIM), the study demonstrates that the nanoscale thickness of the glycocalyx is a critical factor in determining resistance to immune cell attack. By engineering immune cells to express enzymes that can degrade the glycocalyx, such as mucinases and sialidases, the protective barrier can be overcome, enhancing immune cell-mediated cytotoxicity. The study also shows that the protective effect of the glycocalyx is not solely dependent on sialic acid-containing glycans but can be influenced by the physical structure and properties of the mucin layer. By manipulating mucin expression and glycosylation, the thickness and structure of the glycocalyx can be altered, affecting immune cell interactions. Furthermore, the study highlights the potential of using chimeric antigen receptors (CARs) to enhance immune cell killing of mucin-expressing cancer cells. CARs can be engineered to target specific antigens on cancer cells, improving the effectiveness of immune cell-mediated cytotoxicity. Overall, the study provides a framework for understanding how the glycocalyx contributes to immune evasion and how immunoengineering strategies can be developed to overcome this protective barrier. The findings suggest that targeting the glycocalyx through enzymatic degradation or modifying immune cell receptors could be effective strategies for improving cancer immunotherapy.Immunoengineering can overcome the glycocalyx armor of cancer cells. The glycocalyx, a protective layer on cancer cells, shields them from immune attack by modulating interactions with cytotoxic immune cells like NK and T cells. This study shows that the thickness of the glycocalyx, regulated by mucin expression and glycosylation, significantly affects immune cell-mediated cytotoxicity. Mucins, particularly Muc1, form a thick, brush-like layer that protects cancer cells from immune recognition. The thickness of this layer can be altered by modifying mucin expression or glycosylation, which in turn affects immune cell interactions. Using advanced techniques like Scanning Angle Interference Microscopy (SAIM), the study demonstrates that the nanoscale thickness of the glycocalyx is a critical factor in determining resistance to immune cell attack. By engineering immune cells to express enzymes that can degrade the glycocalyx, such as mucinases and sialidases, the protective barrier can be overcome, enhancing immune cell-mediated cytotoxicity. The study also shows that the protective effect of the glycocalyx is not solely dependent on sialic acid-containing glycans but can be influenced by the physical structure and properties of the mucin layer. By manipulating mucin expression and glycosylation, the thickness and structure of the glycocalyx can be altered, affecting immune cell interactions. Furthermore, the study highlights the potential of using chimeric antigen receptors (CARs) to enhance immune cell killing of mucin-expressing cancer cells. CARs can be engineered to target specific antigens on cancer cells, improving the effectiveness of immune cell-mediated cytotoxicity. Overall, the study provides a framework for understanding how the glycocalyx contributes to immune evasion and how immunoengineering strategies can be developed to overcome this protective barrier. The findings suggest that targeting the glycocalyx through enzymatic degradation or modifying immune cell receptors could be effective strategies for improving cancer immunotherapy.