title: Ontogeny of macrophage function to release superoxide anion in conventional and germfree mice.
abstract: To determine whether the presence of bacterial flora contributes to the ontogenic development of macrophage function, the ability of macrophages to release superoxide anion (O2-) in response to stimulation with phorbol myristate acetate was compared in conventional and germfree mice of various ages after birth. One-week-old conventional mice showed a very low level of O2- release by their macrophages, and gradual increases were observed in 2-, 3-, and 4-week-old mice in an age-dependent manner. Macrophages from germfree mice always showed a significantly lower level of O2- release compared with conventional mice of the same age; however, age-dependent functional development was seen also in the germfree group. The poor level of O2- release by macrophages from adult germfree mice could be restored to more than the level by conventional mice when the mice were conventionalized for 3 weeks. These results suggested that the ontogenic development of macrophage function is not controlled by the presence of bacterial flora but that the full-scale expression of function at each age is under the influence of microflora.
mesh_terms: D000367:Age Factors; D000818:Animals; D005856:Germ-Free Life; D007111:Immunity, Cellular; D008264:Macrophages / Q000502:physiology*; D051379:Mice; D010529:Peritoneal Cavity / Q000166:cytology; D013481:Superoxides / Q000378:metabolism*
chemical_list: D013481:Superoxides