Four phases of the primary response a lag phase where no antibody is detected a log phase in which the antibody titer rises logarithmically a plateau phase during which the antibody titer stabilizes a phase(decline)during which the antibody is cleared or catabilizedFour phases of the primary response ◼ a lag phase where no antibody is detected ◼ a log phase in which the antibody titer rises logarithmically ◼ a plateau phase during which the antibody titer stabilizes ◼ a phase (decline) during which the antibody is cleared or catabilized