Humoral Immunity & Cell-Mediated Immunity

Humoral Immunity Vs. Cell-Mediated Immunity

The main differences between humoral immunity & cell-mediated immunity involve activation of varying types of immune cells & response times.

The humoral immune response consists of antibody-mediated immunity. It  involves the B cells & antibodies. Since plasma cells produce antibodies, this is why this type of immunity gets its name. The Greek word “humor” refers to body fluid.

Humoral immunity provides immediate protection against many bacteria and viruses. It produces the five classes of antibodies (IgG, IgA, IgM, IgD, & IgE). Each antibody performs various and specific functions. 

Once a pathogen enters the body, then either the primary or secondary immune response occurs as we reviewed in this video:

When a large molecule enters the body, it usually comes with many different antigens. As a result, antibodies recognize very specific areas on that molecule which are called epitopes or antigenic determinants. The matching area on the antibody is called a paratope or antigen binding site.

Examples of the humoral immune response include anaphylactic shock, eczema, transfusion reactions, and bacterial/viral infections.  

A cell-mediated response happens after a T cell recognizes a specific antigen. This can also be called delayed hypersensitivity. The main immune cells involved are the T cells, macrophages, and natural killer (NK) cells.

Like humoral immunity, cell-mediated immunity protects against bacteria & viruses. It also protects against tumor cells and fungi. The following conditions cause a cell-mediated immune response: toenail fungus, tuberculosis, contact dermatitis, and transplant rejection.

For more details regarding immunology, check out these nursing notes.