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The intracellular survival and growth of gonococci in human phagocytes
Abstract:
In reassessment of previous tests for intracellular survival, results have been confirmed and additional evidence obtained indicating that some gonococci can survive and multiply in human phagocytes. Use was made of the ability of penicillin to penetrate phagocytes and to kill only actively growing organisms. In microscopic counts on 33 urethral exudate smears, an average of 49% of gonococci were associated with polymorphonuclear phagocytes. The organisms were unevenly distributed amongst the phagocytes, with most cells uninfected and some containing large numbers. Many phagocytes also remained uninfected in tests in vitro with low gonococcal inocula although experiments with large inocula showed that most phagocytes could ingest gonococci. It is proposed that ingestion of one gonococcus may stimulate the phagocytes to take up more. Phagocytes were killed and disintegrated after ingesting large numbers of gonococci and similar effect in vivo may be responsible for the large clumps of organisms seen in urethral exudate. These results underline the probable importance in the pathogenesis of gonorrhoea of intracellular survival in phagocytes.
Insights
Gonococci survive and multiply within human phagocytes, challenging previous assumptions. This intracellular survival is crucial to understanding the pathogenesis of gonorrhea.
Area of Science:
- Microbiology
- Immunology
- Pathogenesis
Background:
- Previous studies on Neisseria gonorrhoeae intracellular survival were reassessed.
- Evidence suggests gonococci can survive and multiply within human phagocytes.
Purpose of the Study:
- To confirm and provide additional evidence for intracellular survival of gonococci within human phagocytes.
- To investigate the role of phagocyte interaction in gonococcal pathogenesis.
Main Methods:
- Utilized penicillin's ability to penetrate phagocytes and target actively growing bacteria.
- Performed microscopic counts on 33 urethral exudate smears.
- Conducted in vitro experiments with varying gonococcal inocula.
Main Results:
- An average of 49% of gonococci were found associated with polymorphonuclear phagocytes in urethral exudates.
- Gonococcal distribution within phagocytes was uneven; some cells contained large numbers, while many remained uninfected.
- Large gonococcal inocula led to phagocyte death and disintegration, potentially explaining in vivo observations.
Conclusions:
- Intracellular survival and multiplication of gonococci in human phagocytes are confirmed.
- Phagocyte stimulation to ingest more gonococci after initial contact is proposed.
- Intracellular gonococcal survival is likely a significant factor in the pathogenesis of gonorrhea.