Pathogenesis and immunology of Listeria monocytogenes.

Listeriosis is primarily a foodborne disease and the pathogenesis of infection is determined by passage of the organism from the gastrointestinal lumen to the reticuloendothelial cells of the liver and spleen. Subsequent invasive events such as sepsis and meningitis develop. The immune response to Listeria is characterized by early macrophage mediated killing followed by the development of a brisk cell mediated immune response. Humoral immunity appears to play no role in infection in the protected response. Organism specific virulence factors such as hemolysin and actin polymerization factor may play important roles in pathogenesis and also illicit specific immune responses. Immunization against listeriosis has been carried in animals but does not appear feasible for this rare infection in human populations.