Humoral Immunity

HUMORAL IMMUNITY R.HEMNATH

BY

IMMUNITY ABILITY TO RESIST ALMOST ALL TYPES OF ORGANISMS OR TOXINS THAT TEND TO DAMAGE THE TISSUES AND ORGANS IMMUNITY INNATE

ACQUIRED

ACQUIRED IMMUNITY

HUMORAL MEDIATED

CELL IMMUNITY

FORMATION OF B LYMPHOCYTE

ROLE OF MACROPHAGE IN ACTIVATING LYMPHOCYTES MACROPHAGES ARE PRESENT IN SINUSOIDS OF EPITHELIUM OF LYMPHOIDAL ORGANS MOST ANTIGENS COME IN CONTACT WITH MACROPHAGE PHAGOSITIZE THEM ANTIGENIC PRODUCTS ARE LIBERATED IN CYTOSOL AND THEY STIMULATE B CELLS BY CELL TO CELL CONTACT

ROLE OF T CELLS T HELPER CELLS SECRETE SUBSTANCES (LYMPOKINES) ACTIVATE B CELLS

SPECIFIC ATTRIBUTES OF HUMORAL IMMUNITY

MEMORY A FEW OF LYMPHOBLAST DONOT FORM PLASMA CELLS INSTEAD BECOME B LYMPHOCYTES THEY REMAIN DORMANT UNTIL THEY ARE ACTIVATED BY SAME ANTIGEN

DIFFERENCE BETWEEEN SECONDARY &PRIMARY RESPONSE THERE IS A WEEK DELAY IN PRIMARY RESPONSE WEAK POTENCY DELAY IN ANTIBODY PRODUCTION

RESPONSE

ANTIBODIES GAMMAGLOBULINS HEAVY & LIGHT CHAINS VARIABLE PORTION & CONSTANT PORTION VARIABLE PORTION SPECIFICITY OF ANTIGEN CONSTANT DIFFFUSIBILITY ADHERENCE ATTACHMENT TO COMPLEMENT SYSTEM

SPECIFICITY OF ANTIBODY DEPENDS ON AA SEQUENCE IN VARIABLE PORTION AMINOACID GIVES STERIC SHAPE  ANTIGEN BINDS TO ANTIBODY BY  HYDROPHIC BONDING  IONIC BONDING  VANDER WALL  HYDROGEN

AFFINITY CONSTANT

Ka=[BOUND ANTIBODY ANTIGEN] [ANTIBODY]*[ANTIGEN] HIGHER Ka STRONGER THE BOND

CLASS OF ANTIBODY IgG IgA IgM IgD IgE Ig IMMUNOGLOBULIN IgG bivalent 75%

IgE ALLERGY IgM MANY BINDING SITES

MECHANISM OF ATTACK DIRECT ATTACK DIRECT COMPLEMENTARY SYSTEM COMPLEMENTARY

DIRECT ACTION DIRECT AGGLUTINISATION AGGLUTINISATION PRECIPITATION PRECIPITATION LYSIS LYSIS

COMPLEMENT SYSTEM 20 PROTEINS 11 proteins are principle actors C1-C9,B,D CONSTANT PORTION ACTIVATES C1 AND A CASCADE OF REACTIONS BEGIN

FUNCTIONS OPONISATION & PHAGOCYTOSIS C3b LYSIS C5b6789 AGGLUTINISTION NEUTALISATION OF VIRUSES CHEMOTAXIS C5a ACTIVATION OF MAST CELLS C3a,C4a,C5a INFLAMMATORY EFFECTS