The lung is a portal of entry for numerous microbial pathogens, against
which evolution has created an adequate innate and adaptive immune
response. Dendritic cells (DCs) are central to the integration of innate
and specific immunity. These cells are located within the epithelium and
interstitium of the lung where they are influenced by the innate immune
system. Upon recognition and internalization of microbial antigens, DCs
migrate to the draining lymph nodes of the lung to initiate the specific
cellular and humoral immune response. By their capacity to integrate
stimuli derived from the pathogen, the host and the environment, they are
specialized to induce a protective immune response while at the same time
avoiding damage to the host. It is becoming increasingly clear that
dendritic cells are involved in the induction of immunity to viruses,
bacteria, mycobacteria and fungi. Some pathogens subvert the function of
dendritic cells to escape immune recognition. Not surprisingly, if
dendritic cell function fails, the consequence for the host is
immunodeficiency
