Spleen
- It’s in the upper left part of your belly.
- It has cells called T-cells.
- When you get a sickness like infectious mononucleosis (from the EBV virus), your spleen can get bigger because of more T-cells.
Thymus
- This part helps T-cells grow up.
- T-cells are made in your bones but learn in the thymus.
- Some people are born without a thymus, which is called DiGeorge syndrome.
Antibodies (Germ Fighters)
- IgG: These are important for fighting sickness the second time you get it. They can go from a mother to her baby. They also help other germ fighters work.
- IgA: Found in body fluids like spit and tears.
- IgE: This antibody is involved in allergies and fighting worms.
Immunity (How Your Body Fights Sickness)
- Innate Immunity: This is your body’s first way to fight germs. It’s always ready and doesn’t remember past germs. Things like skin and certain cells (neutrophils, macrophages) are part of this.
- Adaptive Immunity: This part of your body’s defense remembers germs it has fought before. It uses special cells (T-cells, B-cells) to fight specific germs.
Transplants (Putting Something from One Body to Another)
- Autograft: From your own body.
- Isograft: Between twins.
- Allograft: Between people of the same type.
- Xenograft: Between different kinds of animals.
Transplant Rejection (When the Body Doesn’t Like the Transplant)
- Hyperacute: Happens very fast (minutes).
- Acute: Happens in weeks or months.
- Chronic: Happens over many months or years.
Allergies (When Your Body Reacts Too Much)
- Allergies can be caused by certain genes.
- Examples are asthma, skin rashes, and runny nose.
- Mast cells are important in allergies.
Complement System (Germ-Fighting Helpers)
- These are proteins that help fight infections.
- They become active when there’s an infection.
- They help in different ways, like making it easier for other cells to eat germs and creating holes in germs.
- If some of these proteins don’t work right, it can lead to certain infections.
Therapeutic Antibodies (Special Medicines)
- These are man-made antibodies used as medicine for different sicknesses.
- Denosumab: For weak bones.
- Omalizumab: For asthma.
- Pavilizumab: For a lung sickness in babies.
- Eculizumab: For a blood problem.
- Efalizumab: For a skin problem.
- Natalizumab: For a brain and spinal cord problem.
- Trastuzumab: For a type of breast cancer.