Phagocytic WBCs recognize invaders, then track and pursue them. At the same time, the blood vessel walls become porous, allowing the phagocytes easier access to the affected tissue. Enzymes within the phagocyte help digest and neutralize them. When digestion is complete, some debris may leak from the phagocyte into the extracellular fluid. This WBC migration, phagocytosis, and leakage all contribute to inflammation.
Specific immunity is more complicated .
When pathogens enter the body, certain types of lymphocytes see them as antigens, then bind to them and produce antibodies against them. Immunity is specific because the antibodies target only the antigen that triggered their production. If the antigen is one that formerly triggered antibody production, other lymphocytes recognize it and call out antibodies that were produced during the patient's initial exposure. Assessing the pattern of play To balance its defenses, the body normally produces predictable patterns of WBCs. Specific changes in WBC patterns characterize certain problems.