SOUNDARYA .V I BDS 2009-2010
- Is defined as the capacity of the body to resist the pathogenic agents.
- Ability of the body to resist the entry of different foreign substances like bacteria, virus , toxic substances.
- Precursors in the bone marrow.
- During fetal development.
- Released into circulation.
- T - Lymphocytes and B- Lymphocytes.
- Formation during period between birth and few months after birth .
- 60-80% of the circulating lymphocytes.
- Receptors are present on the surface.
- Form a series of a protein mediators called L YMPHOKINES.
- Stimulation & growth of killer cells.
- Feedback stimulation of other helper cells.
- Activation of macrophages system.
- Kill and attack the micro-organisms.
- Are activated by the helper T –cells.
- Have receptors present on the membrane which bind to the antigens.
- Cells release a lysosomal enzyme which punctures holes on the antigens.
- Suppresses the functions of both the cytotoxic and helper cells .
- Prevent excessive immune reactions that may harm the body.
- Memory cells identify the organism for the second time and activate the other T –cells.
- Plasma cell & Memory cells.
- Third type – non T , non-B cells.
- Hydrolytic enzymes - lysis
- Substances that induce specific immune reactions.
- Antigenicity- more molecular weight, more antigenic.
- Proteins / Polysaccharides, complex lipids.
- Produced due to antigenic stimulus and react specifically with it.
- Formerly known as gamma globulins.
- All antibodies are Immunoglobulin and all immunoglobulin are not antibodies
- Linked by di -Sulphide bonds.
- Variable & Constant region.
- Due to protein in circulation called
- Insulin Dependent Diabetes Mellitus.