How do leukocytes fight infection

White blood cells are also called leukocytes. They protect you against illness and disease. Think of white blood cells as your immunity cells. In a sense, they are always at war. They flow through your bloodstream to fight viruses, bacteria, and other foreign invaders that threaten your health. When your body is in distress and a particular area is under attack, white blood cells rush in to help destroy the harmful substance and prevent illness.

White blood cells are made in the bone marrow. They are stored in your blood and lymph tissues. Because some white blood cells called neutrophils have a short life less than a day, your bone marrow is always making them. They have a longer lifespan than many white blood cells and help to break down bacteria.

They create antibodies to fight against bacteria, viruses, and other potentially harmful invaders. Stem cells in the bone marrow are responsible for producing white blood cells. When an infection or inflammatory condition occurs, the body releases white blood cells to help fight the infection.

Health professionals have identified three main categories of white blood cell: granulocytes, lymphocytes, and monocytes. The sections below discuss these in more detail. Granulocytes are white blood cells that have small granules containing proteins. There are three types of granulocyte cells:.

These are present when the body fights off chronic infections. According to an article in American Family Physician , the normal range per cubic millimeter of white blood cells based on age are:. Doctors may continually monitor white blood cells to determine if the body is mounting an immune response to an infection.

During a physical examination, a doctor may perform a white blood cell count WBC using a blood test. They may order a WBC to test for, or rule out, other conditions that may affect white blood cells. Although a blood sample is the most common approach to testing for white blood cells, a doctor can also test other body fluids, such as cerebrospinal fluid, for the presence of white blood cells.

The following are conditions that may impact how many white blood cells a person has in their body. Immunoglobulins commonly known as antibodies are used to treat people who are unable to make enough of their own, or whose antibodies do not work properly. This treatment is known as immunoglobulin therapy. Until recently, immunoglobulin therapy in Australia mostly involved delivery of immunoglobulins through a drip into the vein — known as intravenous immunoglobulin IVIg therapy.

Now, subcutaneous immunoglobulin SCIg can be delivered into the fatty tissue under the skin, which may offer benefits for some patients. This is known as subcutaneous infusion or SCIg therapy. Subcutaneous immunoglobulin is similar to intravenous immunoglobulin. It is made from plasma — the liquid part of blood containing important proteins like antibodies.

Download the SCIg introduction fact sheet to read more about this type of treatment. Many health services are now offering SCIg therapy to eligible patients with specific immune conditions. If you are interested, please discuss your particular requirements with your treating specialist.

Immunisation works by copying the body's natural immune response. A vaccine a small amount of a specially treated virus, bacterium or toxin is injected into the body.

The body then makes antibodies to it. If a vaccinated person is exposed to the actual virus, bacterium or toxin, they won't get sick because their body will recognise it and know how to attack it successfully. Vaccinations are available against many diseases, including measles and tetanus. The immunisations you may need are decided by your health, age, lifestyle and occupation.

Together, these factors are referred to as HALO, which is defined as:. View the HALO graphic to find out more. This page has been produced in consultation with and approved by:. For unexpected after-hours medical issues, there are telephone helplines, pharmacies, after-hours medical clinics or doctors who can visit you at home. Severe allergic reactions anaphylaxis and asthma attacks need urgent emergency first aid. In an emergency, always call triple zero Allergy occurs when the body overreacts to a 'trigger' that is harmless to most people.

Allergies to insect stings and bites range from milder allergic reactions to life-threatening, severe allergic reactions anaphylaxis. All medication has the potential to cause allergies but some people can have allergic reactions to specific prescription or over-the-counter medications.

Content on this website is provided for information purposes only. Information about a therapy, service, product or treatment does not in any way endorse or support such therapy, service, product or treatment and is not intended to replace advice from your doctor or other registered health professional.

The information and materials contained on this website are not intended to constitute a comprehensive guide concerning all aspects of the therapy, product or treatment described on the website. Infections usually cause an elevated white blood cell count, but there are also other possible causes. WBC counts can be increased by overproduction. In other words, the body may release white blood cells early from the bone marrow.

Stress of any form can result in this release of white blood cells. Some causes of an increased white blood cell count include:. In severe infections, immature white blood cells called blasts may be present. Blasts often appear when the body attempts to get white blood cells on the scene quickly. Conditions that may result in a low white blood cell count include:.

On its own, a low WBC count doesn't have symptoms. But a low count will often lead to an infection, because not enough white cells are present to fight off the invader. Symptoms of infection may include:. One of chemotherapy's most common and dangerous side effects is its effect on white blood cells known as neutrophils. Recall that neutrophils are the first responders of our immune system. A decrease in neutrophils during chemotherapy, known as chemotherapy-induced neutropenia , increases the risk of serious infection.

Neutropenia makes it more difficult for the body to fight off infections. As a result, bacteria that are normally not very harmful can cause serious illness. White blood cells are an important part of our immune system. Different types of white blood cells perform different functions in the body.

Overall, white blood cells help to protect us against bacteria, viruses, and parasites. A high white blood cell count is usually a sign of an infection or illness. A low white blood cell count can indicate another type of problem. Low white blood cell counts can leave you vulnerable to serious infections. Chemotherapy is a common cause of low white blood cell counts. Sign up for our Health Tip of the Day newsletter, and receive daily tips that will help you live your healthiest life.

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