27/10/2026
white cell
White blood cells (leukocytes) are color-free immune cells produced in the bone marrow that protect your body from infections, viruses, bacteria, and foreign invaders.
You can read more about blood cell definitions on the National Cancer Institute.
Types of White Blood Cells
• Neutrophils: First-responder cells that act fast to destroy bacteria and fungi.
• Lymphocytes: T cells and B cells that target viral infections and create antibodies for long-term immunity.
• Monocytes: Scavenger cells that clean up damaged tissue and swallow germs.
• Eosinophils: Cells that fight parasites and play a role in allergic reactions.
• Basophils: Cells that release chemicals like histamine during allergic or inflammatory responses.
Normal and Abnormal Counts
• Normal Range: Typically between 4,000 and 11,000 cells per microliter of blood in adults.
• High Count (Leukocytosis): Counts above 11,000 cells per microliter can indicate an infection, inflammation, stress, or conditions like leukemia.
• Low Count (Leukopenia): Counts below 4,000 cells per microliter can raise your risk of infection due to bone marrow issues, autoimmune diseases, or medication.
You can check details on testing procedures via the MedlinePlus Medical Test Guide or review clinical criteria through the Cleveland Clinic Overview.
Are you looking at a complete blood count (CBC) lab result, or do you need information on a specific high or low cell type?
Cleveland Clinic
White Blood Cells: Types, Function & Normal Ranges
Definition: White blood cells (leukocytes) are colorless immune cells originating in bone marrow, comprising 1% of blood. Types & Functions: Neutrophils (kill b...
MedlinePlus (.gov)
White Blood Count (WBC): MedlinePlus Medical Test
Definition: A white blood count (WBC) measures leukocytes produced in bone marrow that fight infections and diseases. Five Major Types: Neutrophils, lymphocytes...
Mayo Clinic
High white blood cell count - Causes and definition - Mayo Clinic
Definition: A high white blood cell count is an infection-fighting cell increase, typically exceeding 11,000 cells per microliter of blood in adults, though ref...
YouTube·Peekaboo Kidz
3m
What Are White Blood Cells? - Learn with Dr. Binocs
National Cancer Institute (.gov)
Definition of white blood cell
white blood cell Listen to pronunciation (hwite blud sel) A type of blood cell that is made in the bone marrow and found in the blood and lymph tissue. White bl...
Cedars-Sinai
What Are White Blood Cells? - Cedars
What Are White Blood Cells? Your blood is made up of red blood cells, white blood cells, platelets, and plasma. Your white blood cells account for only about 1%
Al-Mustaqbal University
Types of White Blood Cells
Lymphocytes are one main type of immune cells produced by the immune system. They are white blood cells present in the blood. There are three types of lymphocyt...
Cleveland Clinic
White Blood Cells: Types, Function & Normal Ranges
Definition: White blood cells (leukocytes) are colorless immune cells originating in bone marrow, comprising 1% of blood. Types & Functions: Neutrophils (kill b...
Cedars-Sinai
What Are White Blood Cells? - Cedars
What Are White Blood Cells? Your blood is made up of red blood cells, white blood cells, platelets, and plasma. Your white blood cells account for only about 1%
National Cancer Institute (.gov)
Definition of white blood cell
white blood cell Listen to pronunciation (hwite blud sel) A type of blood cell that is made in the bone marrow and found in the blood and lymph tissue. White bl...
YouTube·Peekaboo Kidz
3m
What Are White Blood Cells? - Learn with Dr. Binocs
Al-Mustaqbal University
Types of White Blood Cells
Lymphocytes are one main type of immune cells produced by the immune system. They are white blood cells present in the blood. There are three types of lymphocyt...
MedlinePlus (.gov)
White Blood Count (WBC): MedlinePlus Medical Test
Definition: A white blood count (WBC) measures leukocytes produced in bone marrow that fight infections and diseases. Five Major Types: Neutrophils, lymphocytes...
Mayo Clinic
High white blood cell count - Causes and definition - Mayo Clinic
Definition: A high white blood cell count is an infection-fighting cell increase, typically exceeding 11,000 cells per microliter of blood in adults, though ref...
