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White Blood Cells

White blood cells protect the body against infection. Some types of white blood cells include lymphocytes, monocytes, and eosinophils.

Each type of white blood cell plays a different role in protecting the body. The numbers of each type of white blood cells give important information about the immune system. Too many or too few of the different types of white blood cells can help find an infection, an allergic or toxic reaction to medicines or chemicals, and many conditions, such as leukemia.

By	Healthwise Staff
Primary Medical Reviewer	Sarah Marshall, MD - Family Medicine
Specialist Medical Reviewer	Douglas A. Stewart, MD - Medical Oncology
Last Revised	June 28, 2011

WebMD Medical Reference from Healthwise

Last Updated: June 28, 2011

This information is not intended to replace the advice of a doctor. Healthwise disclaims any liability for the decisions you make based on this information.