Immunotherapy 12.1: The Logic of Immunity Quiz

• Dendritic cells are key players in the immune system, they engage with pathogens, they migrate to lymph nodes and activate naive T-cells.
• Activated T-cells can respond specifically to the pathogen, they mature, proliferate and differentiate into effector T-cells and memory T-cells.
• B-cells, activated by helper T-cells, generate antibodies to neutralize, opsonize and complement pathogens.
• T-cells are a crucial part of the immune system, they are our last line of defense against pathogens and cancer. Effector T-cells kill infected cells and activate other immune cells.
• Helper T-cells stimulate immune responses by activating other immune cells such as B-cells and macrophages. Regulatory T-cells suppress immune responses to prevent autoimmunity.
• The immune system has to deal with various challenges, including recognizing self vs foreign, active vs suppressed, and specific mechanisms to control immune responses.
• Pathogens can evade the immune system by mutating, hiding, or inducing immunosuppression.
• Immunotherapies aim to engineer the "right type of response" rather than a "strong response," using mechanisms such as immunosuppression, immune-stimulation, and full replacement of immune cells.
• CAR-T therapy, a type of immunotherapy, involves engineering a patient's T-cells to recognize and attack cancer cells. It's effective against liquid tumors but less so against solid tumors and can have side effects like cytokine storm, CAR lymphomas, and safety concerns.
• Checkpoint blockade therapy, another type of immunotherapy, uses antibodies to block "off switches" on T-cells, allowing them to attack cancer cells. It has seen great success in solid tumors but can have safety concerns, such as rare fatal autoimmune reactions and variable responses depending on the cancer.
• Immunotherapies using memory T-cells and engineered responses like natural killer cells and checkpoint blockade therapy in macrophages are also being explored. The immune system has a short window of time to reverse "exhausted" T-cells back to effector T-cells before they reach a point of irreversibility.

Test your knowledge on the general logic of immunology and the multi-layered defense system. Explore concepts such as innate and adaptive immunity, the first line of immunity, and the requirements for triggering adaptive immunity.