Question

What is cell mediated immunity?

Hint:

Antibody-based defense = Humoral immunity. T-cell based defense = Cell mediated immunity.

Answer 1

Step 1: Definition.
Cell-mediated immunity (CMI) is an immune response that does not involve antibodies but instead uses T-lymphocytes to destroy infected or abnormal cells.
Step 2: Mechanism.
1. Antigen-presenting cells present antigens to T-helper cells.
2. Cytotoxic T-cells are activated.
3. These T-cells destroy virus-infected cells, tumor cells, or transplanted tissues.
Step 3: Importance.
CMI provides defense against intracellular pathogens (viruses, some bacteria) and cancer cells.
Step 4: Conclusion.
CMI is an essential defense mechanism mediated by T-cells rather than antibodies.