Our body defense system can be:
- Non-specific or
Will defend the same no matter what they are, or where they are.
There are some types of Non-Specific
- Physical Barrier
- Phagocyte cells
- Immunological surveillance
- Skin (epithelium with its multiple layers of keratinized cells and desmosomes intercellular connections.
- Cilia - Hairs prevent insects from having easy access to the surface of the body.
- Secreations (from sebaceous and sudoriferous glands not only flush the surface to keep it washed clean of microbes but they also contain antibodies, enzymes (lysozyme) and bactericidal chemicals.
- Epithelia of the digestive, respiratory, urinary and reproductive tract are delicate.
- Mucus bathes the srufaces of the distrive tract ad the stomach has very low pH which will kill bacteria. Alos moves over the lining of the respiratory tract, urine flushes out the urinary tract and glandular secretions clean the reproductive tract.
- Engulf microorganisms and damaged cells.
- Neutrophils and eosinophils leave the bloodstream and enter into the peripheral tissue.
- Neutrophils are abundant, mobile and phagocyte
- Eosinophils target foreign compounds or pathogens which have been coated with antibodies.
- Mostly are Monocytes
- Macrophage phagocytoses foreign objects or secrete lysozyme, hydrogen peroxide or several other factors into the interstitial fluid to destroy the foreign body.
- There are 2 types of macrophages:
- Fixed Macrophages
- Free Macrophages
- Known as : Microglia and Kupffer cells or stellate reticuloendothelial cells)
- Are stationary in their tissue and do not leave them (lung, liver, brain, spleen, lypmph nodes, and bone marrow
- Travel through the body
- They are derived from monocytes of the blood.
The movement of macrophages and microphages through the capillary walls and into the surrounding tissues.
The attraction or repelling of macrophages by chemicals in the surrounding fluids is
The initial binding that occurs between the macrophage and the target just prior to phagocytosis
- It is the constant monitoring of the tissue by NK cells.
- NK Cells will phagocytose any cell which contains abnormal antigens which are not native to your system.
- Small protein which are released by activated lymphocytes and macrophages and by tissues infected with viruses.
- IT DO NOT prevent viruses from entering a cell, BUT they do interfere with the viruses ability to replicate.
- They also attract NK Cells,
- Increase phagocytic activity and
- slow inflammation in a damaged area to slow the spread of a viral infection