White Blood Cell, Types, Function, Range and More

 

Your immune system's white blood cells help shield your body from illness. These cells move through your tissues and bloodstream, combating any foreign organisms that enter your body in response to disease or damage.

White Blood Cells: What are They?

Leukocytes, another name for white blood cells, are what keep your body free from illness. White blood cells circulate in your bloodstream and react to damage or disease as a component of your immune system.

The bone marrow produces white blood cells. Your lymphatic and blood tissues hold them. Your bone marrow produces neutrophils constantly because these white blood cells have a short lifespan—less than a day.

Function:

What do White Blood Cells do?

Your body is protected from infection by white blood cells. Your white blood cells find the infection site as they move through your tissues and bloodstream. They then function as an army general, alerting other white blood cells to their position so they can help protect your body from an unknown organism's onslaught. Your army of white blood cells will battle the intruder by creating antibody proteins that will adhere to and destroy the invader once it has arrived.

Anatomy:

Where are White Blood Cells Located? 

Your white blood cells are in your bloodstream and travel through blood vessel walls and tissues to locate the site of an infection.

 What do White Blood Cells Look Like?

 Contrary to their name, white blood cells are colorless but can appear as a very light purple to pink color when examined under a microscope and colored with dye. These extremely tiny cells have a round shape with a distinct center membrane (nucleus).

Also Read: Blood Cell, Types and Functions

White Blood Cell Types:

White blood cells are divided into five categories mostly according to whether or not they have granules.

Granulocytes: They belong to the category of white blood cells that have granules in their cytoplasm. Among the granular cells are:

• Neutrophils
• Basophil
• Eosinophi

Agranulocytes: are white blood cells that do not contain granules in their cytoplasm. Among the a-granulated cells are:

• Monocytes
• Lymphocytes

Neutrophils:

 By eliminating bacteria, fungus, and foreign debris, neutrophils aid in the body's defense against infections.

Approximately 50% of the white blood cells in the body are neutrophils. When bacteria or viruses penetrate the body, these immune system cells typically react to them first.

In addition to acting as first responders, they also send out signals requesting assistance from other immune system cells. The primary cells in pus, the white substance that may be visible inside a wound or pimple, are neutrophils. 

The cells are only viable for roughly eight hours after being taken out of the bone marrow. Approximately 100 billion of these cells are produced daily by your body.

The Typical Range and Prevalence of Neutrophils:

About 40–75% of all white blood cells in an adult body are of this kind, which is the most prevalent kind.

A complete blood count includes a neutrophil count. Neutrophils typically have a count of between 2500 and 7500 per microliter of blood.

An Illness that Impacts Neutrophils:

Neutropenia is a disorder in which the body's neutrophil count is abnormally low compared to normal limits, leading to recurrent infections and edema. Neutropenia is primarily caused by cancer treatment, infections (hepatitis, tuberculosis, sepsis, Lyme disease), bone marrow disorders, vitamin deficiencies, and autoimmune diseases or infections.

Neutrophilia, also known as neutrophilic leukocytosis, is a condition in which neutrophil count is greater than normal ranges. The main causes of neutrophilia are bacterial infection, inflammation, injury, medication reactions, and immature neutrophils that leave the bone marrow too fast and enter the bloodstream.

Eosinophils: 

Eosinophils are involved in the defense against bacterial and parasitic illnesses (worms, for example).

The most well-known function of eosinophils is to cause allergic symptoms. When developing an immune reaction against something that is truly innocuous, these white blood cells tend to overreact. Eosinophils, for instance, may misinterpret pollen for an alien invasion and cause symptoms associated with seasonal allergies. Additional symptoms of eosinophilia include fever, sweats during the night, exhaustion, and weight loss.

The percentage of white blood cells in your blood that are eosinophils is just approximately 5%. Eosinophil concentrations are quite high in the digestive tract.

Eosinophil Normal Ranges and Prevalence:

One to four percent of all white blood cells are eosinophils.

A full blood count includes the measurement of eosinophils; the typical range for neutrophil counts is 100–400 per microliter of blood.

A Condition that Affects: 

 Eosinopenia: It is the condition of eosinophils counts lower than the normal range in our body. Cushing’s syndrome and sepsis are common causes of Eosinopenia. 

Eosinophilia: It is the condition of eosinophils counts higher than the normal range. Alcohol intoxication, allergies, gastrointestinal disorders, leukemia, overproduction of cortisol, and parasitic infection are causes of eosinophil condition.

Basophils:

 Cause an allergic reaction that manifests as runny nose, coughing, or sneezing.

Although basophils make up only 1% of white blood cells, they play a major role in asthma and are a component of your body's basic immune response to pathogenic organisms. When basophils are stimulated, they release chemicals such as histamine that cause inflammation in the body and narrowing of the airways.

The Typical Range and Prevalence of Basophils:

 White blood cells, or leukocytes, make up only 0.5 to 1% of total blood cells; the usual range of counts is 25–200 per µl.

A Condition that Impacts Basophils: 

Basopenia: The disorder known as basopenia is caused by the body producing insufficient amounts of basophil.  Perhaps basopenia is a comorbidity of hyperthyroidism.

Basophilia: When the body creates an excessive number of basophil cells, it is known as basophilia. Basophilia is a disorder associated with leukemia, polycythemia vera, myelofibrosis, hypothyroidism, and autoimmune diseases.

Monocytes:

 Repair damaged cells to prevent infection.

Approximately 5% to 12% of the white blood cells in your blood are monocytes. Their primary function is to eliminate dead cells from the body; they function as the immune system's "garbage trucks."

Monocyte Prevalence and Normal Ranges:

 It is the largest type of white blood cell but they form only in a small proportion; it consists of 2-8% of all white blood cells in an adult body. Monocyte count is part of a complete blood count; the normal range of monocyte counts ranges from 100-700 per µl of blood.

A Condition that Affects Monocytes:

Monocytopenia: When our monocyte count is too low, monocytopenia occurs. This condition occurs as a result of decreases in our leukocytes. Aplastic anemia, blood infection, burn injuries, HIV, and reaction to chemotherapy are common causes of monocytopenia.

Monocytosis: It is the condition when the monocyte count is too high. Autoimmune disease (lupus disease, rheumatoid arthritis), blood disorders, cancer, cardiovascular disease, infection, and inflammatory disease are common causes of monocytosis.

Lymphocytes:

 B cells and T cells make up lymphocytes, which help create antibodies to combat infection and protect against viral infections.

The immune response mediated by antibodies is known as humoral immunity, and it is primarily the function of B lymphocytes (B cells). Antibodies that "remember" an infection are produced by B cells. These antibodies are always prepared if your body comes into contact with the same infection again.

T cells identify and eliminate particular foreign invaders. After an infection, "memory" T cells also recall the invader and react fast if it resurfaces.

Part of what makes immunizations effective is lymphocytes. After receiving a vaccination, your body produces B and T cells that will enable you to identify the pathogen and prepare you to fight it off if you are ever exposed.

The Typical Range and Prevalence of Lymphocytes:

The usual range of lymphocytes, which make up about 20–30% of all white blood cells, is 1500–2700 per microliter of blood.

Lymphocytes can live anywhere from a few days to many years. Long-lived lymphocytes are essential for immune memory preservation. 

An Illness that Impacts Lymphocytes:

Lymphocytopenia: Low levels of lymphocytes are known as lymphocytopenia. Low lymphocyte counts can be brought on by the flu, a minor infection, a viral infection, TB, autoimmune diseases, blood disorders, radiation, and chemotherapy treatment.

Lymphocytosis: The condition known as lymphocytosis is characterized by a high lymphocyte count. Higher lymphocyte counts can be caused by blood cancer, syphilis, mononucleosis, TB, viral infections, hypothyroidism, etc.

Disorders and Conditions:

A low white blood cell count increases your risk of leukopenia or infections. You might have an infection or an underlying medical disease such as leukemia, lymphoma, or an immunological disorder if your white blood cell count is very high, also known as leukocytosis.

What are Typical Indicators or Symptoms of Disorders Affecting White Blood Cells?

White blood cell disorders can cause you to have an abnormally high or low count. Some symptoms include:

• Chills, fever, and body aches.
• A wound that is pus-filled, red, bloated, or refusing to heal.
• Frequent infections.
• Breathing difficulties or persistent coughing.

What Percentage of White Blood Cells is Normal?

It's typical for you to generate close to 100 billion white blood cells daily. A test counts your white blood cells, or the amount of cells per microliter of blood after the blood draw is finished. White blood cells typically have a density of 4,000–11,000 per microliter.

Which Tests are Frequently Used to Measure White Blood Cell Counts?

The results of a complete blood count (CBC) test reveal details about the cells in your blood. After a medical practitioner takes your blood and counts your white and red blood cells, a lab performs this test.

A white blood cell scan looks for infections or abscesses in the soft tissues of your body. In this test, your blood is drawn, the white blood cells are separated from the sample, labeled with a radioactive isotope, and then the white blood cells are put back into your body. An imaging test is then performed to find any locations on your body that exhibit signs of infection or abscess.

Why is the White Blood Cell Count Low?

Low white blood cell counts can be caused by the following factors:

• Failure of the bone marrow (aplastic anemia).
• Cancer cells attacking the bone marrow (leukemia).
• Exposure to drugs (chemotherapy).
• A shortage of vitamins (B12).
• HIV/AIDS.

Low white blood cell counts are identified by a blood test that finds less than 4,000 cells per microliter of blood.

Why is the Count of White Blood Cells High?

High white blood cell counts can be caused by the following factors:

• Autoimmune diseases, such as rheumatoid arthritis and lupus.
• Viral diseases (mononucleosis, TB).
• Infections with bacteria (sepsis).
• Physical harm or tension.
• Either Hodgkin's disease or leukemia.
• Allergies.

High white blood cell counts are identified by a blood test that finds more than 11,000 cells per microliter of blood.

What Common Treatments Exist for Conditions Involving White Blood Cells?

The severity and diagnosis of white blood cell abnormalities determine the course of treatment. The spectrum of treatment includes:

• Taking vitamins.
• Taking antibiotics.
• Bone marrow replacement or repair surgery.
• Transfusion of blood.
• Transplant of stem cells.