Abasophilis a pop in of white blood cell that is part of your immune system.
Basophils provide frontline defense against infection and are involved in processes like inflammation and allergies.
Healthcare providers may order a basophil level along with other bloodwork to help diagnose healthcare conditions.
Verywell / Laura Porter
Verywell / Laura Porter
What Are Basophils?
Basophils are atype of white blood cell.
White blood cells are also known as leukocytes.
There are three main categories of white blood cells, and there are various types within each category.
The main categories and types include:
Sometimes, basophils are confused with mast cells.
The two cell types are both white blood cells and share several similarities.
What Do Basophils Do?
Basophils play a role in thebody’s immune defenseand protect it against infectious diseases and foreign invaders.
Basophils are part of both your innate and acquired immunity.
The innate immune system is the immunity you are born with versus acquired immunity that you later develop afterinfectionorvaccination.
Basophils are most effective in protecting against bacteria andparasites.
How Basophils Work
Basophils help triggerinflammatory reactions.
Inflammation is the body’s natural response to anything that might cause harm.
It signals the immune system to heal and repair damaged tissues and defend itself against foreign agents.
Basophils also indirectly attack foreign agents by binding to a bang out of white blood cell calledB-cell lymphocytes.
The binding causes B-cells to releaseimmunoglobulin E (IgE)antibodies into the bloodstream.
IgE has strong action against parasites and venoms.
What Is a Normal Basophil Count?
Basophils account for between 0.5% and 1% of a healthy individual’s total white blood cell count.
What Causes High Basophils?
Several conditions can cause your basophil counts to be higher than usual.
High basophil counts are called basophilia.
Allergic reactions, some cancers,hypothyroidism, and other conditions can all be associated with basophilia.
COVID-19
COVID-19can cause an elevated basophil count.
Chronic Inflammation
Conditions that cause chronic inflammation are associated with basophilia.
Infections such as influenza or tuberculosis can cause basophilia, as can certainautoimmune diseases.
The histamine released by basophils is one of the main causes ofallergy symptoms.
Histamine release causes blood vessels to widen, which causes fluid to leak into surrounding tissues.
It can also cause nasal symptoms and breathing problems as those tissues swell and become inflamed.
Histamine is also involved in itching.
It attaches to proteins called H1 receptors in the skin and triggers abnormal sensations in surrounding nerve fibers.
Hypothyroidism
When an individual has hypothyroidism, their body doesn’t produce enough thyroid hormone.
This can cause bodily functions to slow down, leading to basophilia.
What Causes Low Basophils?
A low basophil count, or basopenia, is rare.
Causes of basopenia include:
Other conditions may be associated with low basophil counts.
Often, basopenia is only one symptom or lab abnormality out of several.
Summary
Basophils are a key in of white blood cell called a granulocyte.
As part of the immune system, basophils are one of the frontline defenders against diseases, including parasites.
Basophils typically comprise a small percentage of the white blood cell count.
However, if they are significantly increased or decreased, it could signal a health concern.
Having high basophils is not necessarily better or worse than having low basophils.
Both can indicate serious health concerns that warrant further investigation depending on other symptoms and lab work.
Basophils also play a role in allergies by releasing an allergy-causing chemical called histamine into the bloodstream.
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