What is a white blood cell (WBC)?

William Lee Dubois
Endocrinology Diabetes & Metabolism
White blood cells (WBC) are like an army. They patrol your body constantly, on the lookout for attacks from viruses, bacteria, and other infections. If the scouts find a problem, they sound the alarm and the troops swarm to the site of the attack.

And just like a military is made up of Army, Navy, Marines, and Air Forces, the WBC army also has specialists with names like Neutrophil, Esoniophil, Basophil, Lymphocyte, and Macrophage.

Each "branch" of the WBC military specializes in fighting different kinds of invaders.

One cool thing about blood cells in general is that, unlike most cells that reproduce by dividing, blood cells are manufactured in the bone marrow.

A WBC count is part of a blood test called a Complete Blood Count. An elevated WBC would serve as a marker of infection, as an unusual number of "troops" shows an invasion has taken place.

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Important: This content reflects information from various individuals and organizations and may offer alternative or opposing points of view. It should not be used for medical advice, diagnosis or treatment. As always, you should consult with your healthcare provider about your specific health needs.