Effect of anaerobiosis and sulfide on killing of bacteria by polymorphonuclear leukocytes.

Anaerobic microorganisms in periodontal pockets produce toxic amounts of hydrogen sulfide. The capacity of polymorphonuclear leukocytes to kill a capsulated and a non-capsulated variant of a group B streptococcal strain was studied in presence and absence of sulfide. The killing was equally efficient under aerobic and anaerobic conditions.

Adherence and surface properties of buoyant density subpopulations of group B streptococci, type III.

From clinical isolates of group B streptococci, buoyant density subpopulations with variable amounts of type-specific polysaccharide can be derived. The ability of these subpopulations to adhere to vaginal epithelial cells and to glass was assessed by using [3H]-labeled bacteria. Subpopulations with no or minute amounts of capsule showed good adherence capacity and a hydrophobic cell surface.

Effect of sulfide ions on complement factor C3.

In infected sites such as the gingival pockets of patients with periodontal disease, sulfide levels up to 1 mmol/liter may be reached. There is little information, however, on how sulfide may interact with the host defense. In a previous study (R.

Demonstration and characterization of buoyant-density subpopulations of group B Streptococcus type III.

Group B Streptococcus (GBS) type III (18 strains) was investigated for the presence of buoyant-density subpopulations; 10 strains originated from invasive isolates causing early-onset septicemia, and 8 were colonizing isolates from pregnant women. By repeated processing in hypotonic density gradients of Percoll, high- (HD) and low-density (LD) subpopulations were recovered from all strains. Synthesis of type-specific polysaccharide (TPS) was increased in the invasive isolates and their respective LD variants compared with the colonizing strains and their LD subpopulations.

Activity of polymorphonuclear leukocytes in the presence of sulfide.

Polymorphonuclear leukocytes (PMN) isolated from human blood were exposed to various levels of hydrogen sulfide. The effect on respiratory burst, myeloperoxidase activity, and capacity to phagocytose and kill bacteria were studied. A 1-h exposure of the PMN to 1 mM sulfide did not decrease their myeloperoxidase activity or their capacity to initiate a respiratory burst.