KARASHIMA R, YAMAKAMI Y, YAMAGATA E, KAMBERI P, NAGAI H, NASU M; Interscience Conference on Antimicrobial Agents and Chemotherapy.
Abstr Intersci Conf Antimicrob Agents Chemother Intersci Conf Antimicrob Agents Chemother. 1999 Sep 26-29; 39: 584 (abstract no. 2011).
2nd Dept. of Internal Med., Otia Med. Univ., Otia, JAPAN.
BACKGROUND: Some of clinically important fungi, such as Candida albicans and Cryptococcus neoformans, have been known to change their phenotypes by in vivo passage. However, there are no reports describing this phenomenon in Trichosporon species. We investigated whether phenotypes of environmental Trichosporon asahii isolates would be changed by in vivo passage.METHODS: Four environmental and 20 clinical T. asahii isolates were used. Each isolate was characterized by colony and cell morphology, glucuronoxylomannan (GXM) and (1[TM] 3)-beta-D-glucan production by using a latex agglutination test and G-test, and virulence for mice. Then, all environmental isolates were passaged 3 times through ICR murine hosts. The passaged isolates were re-characterized and compared with original ones.RESULTS: There were clear differences in cell morphology and GMX production between environmental isolates and clinical isolates. GMX production was significantly higher in clinical isolates than in environmental isolates (titer: log[2]5.18+/-1.03 vs. log[2]9.38+/-0.58, p<0.01). The passaged isolates were shown to differ from their original isolates in their cell morphology, GXM production (titer: log[2]10.0+/-0.63 vs. log[2]5.18+/-1.03, p<0.01), and virulence for mice.CONCLUSION: The results suggest microevolution of T. asahii during infection. This process may allow the fungal population to escape eradication by the immune system because GXM are considered to protect the fungi from phagocytosis by polymorphonuclear cells and monocytes.
Publication Types:
Keywords:
- Animals
- Antigens, Fungal
- Basidiomycota
- Cryptococcosis
- Cryptococcus neoformans
- Mice
- Mice, Inbred ICR
- Monocytes
- Phagocytosis
- Phenotype
- Polysaccharides
- Trichosporon
- Virulence
- genetics
- glucuronoxylomannan
- immunology
Other ID:
UI: 102246858
From Meeting Abstracts