Active antibodies are antibodies induced in organisms by exposure to antigens. This is mediated by two well-defined mechanisms:
What is Humoral Immunity?
Humoral immune activity is one of the functional mechanisms of the immune system and unlike antibodies it is associated with circulating antibodies Various immune functions they quickly reactivate antigen-specific B cells during infection to increase antibody levels with increased engagement with the stimulus and another directed effective response. .
What is Cell-Mediated Immunity?
Cell-mediated immunity is a type of adaptive immune response that does not involve antibodies but involves the activation of NK cells and macrophages and the production of antigen-specific cytotoxic T-lymphocytes and the release of several cytokines in response to foreign antigens.
Cell-mediated immunity plays an important role in controlling protozoan infections such as virus, chlamydia, rickettsia and trypanosomes because antibodies cannot penetrate and attack pathogens in proliferating cells within host cells.
Difference Between Humoral And Cell Mediated Immunity
| Cell-mediated Immunity | Humoral Immunity |
| It is mediated by T-cells. | It is mediated by B-cells. |
| No formation of antibodies. | Formation of antibodies. |
| Receptors are made used to identify antigens. | Antibodies are made used to identify antigens. |
| T-cell receptors bind to the T-cell, and the T-cells stick to the antigens. | The antibodies produced by B-cells stick to the antigen. |
| It protects against viruses, fungi and other intracellular bacterial pathogens. | It protects against extracellular viruses and bacteria. |
| It can eliminate tumour cells and thus protects against cancer. | It cannot eliminate tumour cells. |
| Both CD4+ and CD8+ cells participate in cell-mediated immunity. | Only TH cells participate in humoral immunity. |
| Mediates hypersensitivity type IV. | Mediates hypersensitivity I, II and III. |
| It shows a delayed response. | It is quick in response. |
Following are the similarities between cell-mediated and humoral immunity:
- Both humoral and cell-mediated immunity are active immunities.
- Both have a lag period.
- Both are active against a wide variety of pathogens.
- Both possess immunological memories.
- Both systems are not effective in immune-deficient individuals.
