IMMUNOGLOBULIN

Course overview

IMMUNOGLOBULINS (IG) OR ANTIBODIES ARE GLYCOPROTEINS THAT ARE PRODUCED BY PLASMA CELLS. B CELLS ARE INSTRUCTED BY SPECIFIC IMMUNOGENS, FOR, EXAMPLE, BACTERIAL PROTEINS, TO DIFFERENTIATE INTO PLASMA CELLS, WHICH ARE PROTEIN-MAKING CELLS THAT PARTICIPATE IN HUMORAL IMMUNE RESPONSES AGAINST BACTERIA, VIRUSES, FUNGI, PARASITES, CELLULAR ANTIGENS, CHEMICALS, AND SYNTHETIC SUBSTANCES. THE IMMUNOGEN OR ANTIGEN REACTS WITH A B-CELL RECEPTOR (BCR) ON THE CELL SURFACE OF B LYMPHOCYTES, AND A SIGNAL IS PRODUCED THAT DIRECTS THE ACTIVATION OF TRANSCRIPTION FACTORS TO STIMULATE THE SYNTHESIS OF ANTIBODIES, WHICH ARE HIGHLY SPECIFIC FOR THE IMMUNOGEN THAT STIMULATED THE B CELL. FURTHERMORE, ONE CLONE OF B CELL MAKES AN IMMUNOGLOBULIN (SPECIFICITY). BESIDES, THE IMMUNE SYSTEM REMEMBERS THE ANTIGENS THAT CAUSED A PREVIOUS REACTION (MEMORY) DUE TO THE DEVELOPMENT OF MEMORY B CELLS. THESE ARE INTERMEDIATE, DIFFERENTIATED B CELLS WITH THE CAPABILITY TO QUICKLY BECOME PLASMA CELLS. CIRCULATING ANTIBODIES RECOGNIZE ANTIGEN IN TISSUE FLUIDS AND SERUM. THIS ACTIVITY DESCRIBES THE PHYSIOLOGY AND PATHOPHYSIOLOGY OF IMMUNOGLOBULINS.