What type of immunity involves antibodies produced by B-cells?

Humoral immunity specifically refers to the aspect of the immune response that involves B-cells and the antibodies they produce. B-cells are a crucial component of the adaptive immune system, and they respond to specific antigens by differentiating into plasma cells, which then produce antibodies. These antibodies are proteins that can bind to pathogens, neutralizing them or marking them for destruction by other immune cells.

This type of immunity is particularly effective against extracellular pathogens, such as bacteria and viruses that are present outside of cells. The antibodies generated by B-cells circulate in the body's fluids (or humors), hence the term "humoral." Additionally, humoral immunity can also include the memory B-cells created after an initial infection, which enables a faster and more robust response upon subsequent exposures to the same pathogen.

Innate immunity is a general, non-specific defense mechanism that acts as the first line of defense against pathogens, while cell-mediated immunity primarily involves T-cells targeting infected cells and some pathogens that reside within cells. Active immunity involves the development of immunity through exposure to an antigen, which can occur through natural infection or vaccination, but does not inherently specify the role of antibodies produced by B-cells.