THE IMPORTANCE OF IMMUNOGLOBULIN-BREAKDOWN SUPPORTING THE GROWTH OF BACTERIA IN ORAL ABSCESSES

Oral bacteria play an important role in the causation of ore-facial ab scesses. However, they can also be involved in brain, liver and lung a bscesses. To persist, it is essential that these bacteria can grow on those sites. The main source of nutrients for growth in abscesses is l ikely to be tissue exudate, which is rich in serum-derived proteins, a nd relatively poor in free amino acids and carbohydrates. Degradation of intact proteins seems a crucial step in providing the peptides nece ssary for energy generation. The aim of this study was to investigate the capacity of microorganisms from asscesses to degrade serum protein s, in particular immunoglobulins. To this end, samples were taken by a spiration from 16 odontogenic abscesses. It was found that pus from ab scesses differed strongly in the concentration of viable bacterial cel ls. The ability of the abscess microflora to degrade serum proteins wa s investigated after growth of the sample in heat-inactivated human se rum. The microflora from abscesses with a high concentration (n=10) of bacteria strongly degraded immunoglobulins, whereas breakdown of immu noglobulins was virtually absent after growth of the microflora from l ow-bacterial concentration (n=6) abscesses. Bacteriological analyses r evealed the presence of at least one proteinase-producing species, lik e Porphyromonas, black-pigmented Prevotella species, or Actinomyces me yeri, in abscesses with a high density of bacteria, but not in those w ith low bacterial density. The results indicate that the capacity to d egrade intact proteins, in particular immunoglobulins, is a major dete rminant of bacterial growth in abscesses.