Activated B-cell

An activated B-cell is a type of immune cell that has been stimulated to respond to a specific threat, like a pathogen or infection. When your body detects an invader, B-cells recognize it and become activated, meaning they start to grow and divide. These activated B-cells produce antibodies—special proteins that help identify and neutralize the harmful invader. Essentially, activated B-cells are the immune system's way of mounting a targeted defense, remembering the threat, and preventing future infections by quickly responding if the same invader appears again.