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Identifying Dysregulated Genes Induced by Kaposi's Sarcoma-associated Herpesvirus (KSHV)
Published on: September 14, 2010
Unidentified bacterial microorganisms entrapped within blood capillary spaces of tissue from different
1Institute of Molecular Virology, GSF-National Research Center for Environment and Health, Neuherberg, Germany.
Abstract:
Tissue specimens of different epidemiological types of Kaposis sarcoma (KS) from various geographical regions were investigated by transmission electron microscopy. Freshly fixed KS biopsies originated from 9 German patients: 3 classic KS cases, 5 AIDS-associated KS cases, and 1 atypical classic KS case. Additionally, KS autopsy material from the brain of a German AIDS patient was examined. Further biopsies came from 29 Ugandan patients: 16 endemic KS cases and 13 AIDS-associated KS cases. While investigating the ultrastructure, we discovered relatively small-sized bacterial microorganisms within blood capillary spaces of tumor tissue from 5 KS cases of different epidemiological type. The microorganisms often occurred in clusters. They were of coccoid-bacillary form and limited by a wrinkled multilayered cell wall. Many of them were encapsulated. They were not observed outside of the capillary lumen. The bacterial structures were often seen attached to capillary endothelial cells, which sometimes showed blistering into the capillary lumen. The observed bacterial microorganisms obviously represented agents of a bloodstream infection and must have been entrapped and accumulated within capillary spaces of KS tissue. The bacteria, which had an almost identical morphology in all 5 KS cases, could not be identified. If they are of pathogenic significance, it remains unknown.
Insights
Electron microscopy revealed small, encapsulated bacteria within blood capillaries of Kaposis sarcoma (KS) tissue from diverse cases. These microorganisms, possibly from bloodstream infections, were found in 5 KS patients but remain unidentified.
Area of Science:
- Microbiology
- Oncology
- Pathology
Background:
- Kaposis sarcoma (KS) is an opportunistic malignancy.
- KS presents with diverse epidemiological patterns globally.
- Ultrastructural analysis of KS tissue is crucial for understanding its pathogenesis.
Purpose of the Study:
- To investigate the ultrastructure of KS tissue from different epidemiological types and geographical regions.
- To identify any microorganisms present within KS tumor biopsies.
- To determine the potential role of observed microorganisms in KS.
Main Methods:
- Transmission electron microscopy (TEM) was used.
- KS tissue specimens from German and Ugandan patients were analyzed.
- Biopsies included classic, AIDS-associated, and endemic KS cases.
Main Results:
- Small, coccoid-bacillary microorganisms were observed within blood capillary spaces in 5 KS cases.
- These encapsulated bacteria, with a multilayered cell wall, appeared in clusters.
- The bacteria were attached to capillary endothelial cells and not found outside capillaries; their morphology was consistent across cases but they were unidentifiable.
Conclusions:
- Bacterial microorganisms were detected within KS tumor capillaries, suggesting a bloodstream infection.
- The observed bacteria could not be identified and their pathogenic significance in KS remains unknown.
- Further research is needed to identify these bacteria and ascertain their role in Kaposis sarcoma.
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