VMC 221: Veterinary Immunology and Serology (1+1)

INTRODUCTION- SECONDARY BINDING TESTS

• Here the reaction between antigen and antibody is commonly followed by a second reaction.
• The antigen antibody complex formed a stable complex which can be visualized.
• Thus if antibody combine with soluble antigens in solution, the resulting complexes may precipitate.
• If the antigens are particulate (eg: bacteria, RBCs), then antibodies will make them clump or agglutinate.
• If the antibody can activate the classical complement pathway and the antigen is on a cell surface, then lysis of the cell may result.
• The secondary binding tests are
  • Precipitation test
  • Agglutination test