Primary immune response

Primary immune response The primary immune response occurs when a pathogen comes in contact with the The process of production of blood cells in the bone marrow is called haematopoiesis . XII Std Zoology Chapter XII Std Zoology Chapter Immunology Within hours after recognition of the antigen, a new army of plasma cells are generated. Within to days, the antibody concentration in the blood rises steeply to reach much higher level than primary response. This is also called as “ booster response ” .