immunity
TRANSCRIPT
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.
Produced in the thymus .Formation during period between
birth and few months after birth .Thymosin – hormone.60-80% of the circulating
lymphocytes.Cell-mediated immunity.Receptors are present on the
surface.
75% of T-cells.
Form a series of a protein mediators called LYMPHOKINES.
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.
20-25 %.Short life span.Bone marrow.Plasma cell & Memory cells.Humoral immunity.
10-15%Third type – non T , non-B cells.Hydrolytic enzymes - lysis
FUNCTIONS :Destroy malignant cells.Attack viruses.
Substances that induce specific immune reactions.
Antigenicity- more molecular weight, more antigenic.
Proteins / Polysaccharides, complex lipids.
ANTIGENS: Auto antigensForeign antigens
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
STRUCTURE:
Y-shaped. Light chains. Heavy chains. Linked by di -Sulphide
bonds. Variable & Constant
region.
Direct action:Agglutination, Precipitation, Neutralization &Lysis
Complement system:Classical pathway-o C1 binds with antibodies
Alternate pathway-o Due to protein in circulation calledo FACTOR 1.o Activates C3 and C5 .
Insulin Dependent Diabetes Mellitus.Myasthenia Gravis .Grave’s Disease.Rheumatoid Arthritis.