Which blood component plays a key role in the immune response?

Leukocytes, or white blood cells, are integral to the immune response, serving as the body’s primary defense mechanism against infections, foreign invaders, and other threats. They are responsible for identifying, attacking, and destroying pathogens such as bacteria, viruses, and fungi.

Leukocytes encompass various cell types, including lymphocytes (such as T cells and B cells), neutrophils, monocytes, eosinophils, and basophils. Each of these cell types has specific functions, such as producing antibodies, orchestrating inflammatory responses, and directly attacking infected or malignant cells.

In contrast, red blood cells primarily carry oxygen and carbon dioxide throughout the body, and platelets are essential for blood clotting rather than immune defense. Serum contains antibodies and other proteins that can assist in the immune process, but it is the leukocytes that actively perform the immune functions necessary for protecting the body from infections and diseases.