Limits...
Pathogenic diversity amongst serotype C VGIII and VGIV Cryptococcus gattii isolates.

Rodrigues J, Fonseca FL, Schneider RO, Godinho RM, Firacative C, Maszewska K, Meyer W, Schrank A, Staats C, Kmetzsch L, Vainstein MH, Rodrigues ML - Sci Rep (2015)

Bottom Line: This great phenotypic diversity reflected in differential pathogenicity.VGIV isolates WM 779 and 106.97 were similar in their ability to cause lethality and produced higher pulmonary fungal burden in a murine model of cryptococcosis, while isolate ATCC 24066 (VGIII) was unable to reach the brain and caused reduced lethality in intranasally infected mice.These results demonstrate a high diversity in the pathogenic potential of isolates of C. gattii belonging to the molecular types VGIII and VGIV.

View Article: PubMed Central - PubMed

Affiliation: Instituto de Microbiologia Paulo de Góes, Federal University of Rio de Janeiro, Rio de Janeiro, Brazil.

ABSTRACT
Cryptococcus gattii is one of the causative agents of human cryptococcosis. Highly virulent strains of serotype B C. gattii have been studied in detail, but little information is available on the pathogenic properties of serotype C isolates. In this study, we analyzed pathogenic determinants in three serotype C C. gattii isolates (106.97, ATCC 24066 and WM 779). Isolate ATCC 24066 (molecular type VGIII) differed from isolates WM 779 and 106.97 (both VGIV) in capsule dimensions, expression of CAP genes, chitooligomer distribution, and induction of host chitinase activity. Isolate WM 779 was more efficient than the others in producing pigments and all three isolates had distinct patterns of reactivity with antibodies to glucuronoxylomannan. This great phenotypic diversity reflected in differential pathogenicity. VGIV isolates WM 779 and 106.97 were similar in their ability to cause lethality and produced higher pulmonary fungal burden in a murine model of cryptococcosis, while isolate ATCC 24066 (VGIII) was unable to reach the brain and caused reduced lethality in intranasally infected mice. These results demonstrate a high diversity in the pathogenic potential of isolates of C. gattii belonging to the molecular types VGIII and VGIV.

No MeSH data available.


Related in: MedlinePlus

Capsular dimensions and expression of CAP genes in C. gattii.A. India ink counter-staining (left panels) and corresponding capsular dimensions (right panels) of C. gattii after growth in Sabouraud or minimal media. Capsular dimensions of the ATCC 24066 isolate were significantly smaller than those observed for 106.97 and WM 779 isolates (***p = <0.0005). Scale bar: 5 μm. B. Expression of CAP genes under the conditions used for determination of capsular dimensions. CAP59 and CAP60 had their expression significantly altered in the ATCC 24066 isolate (***p = <0.0001; **p = <0.005).
© Copyright Policy - open-access
Related In: Results  -  Collection

License
getmorefigures.php?uid=PMC4495446&req=5

f5: Capsular dimensions and expression of CAP genes in C. gattii.A. India ink counter-staining (left panels) and corresponding capsular dimensions (right panels) of C. gattii after growth in Sabouraud or minimal media. Capsular dimensions of the ATCC 24066 isolate were significantly smaller than those observed for 106.97 and WM 779 isolates (***p = <0.0005). Scale bar: 5 μm. B. Expression of CAP genes under the conditions used for determination of capsular dimensions. CAP59 and CAP60 had their expression significantly altered in the ATCC 24066 isolate (***p = <0.0001; **p = <0.005).

Mentions: Results obtained from serological, morphological and glycosidic composition analyses clearly indicated a high diversity in capsular structures of the herein analyzed C. gattii isolates. To investigate the possibility of additional diversity at the molecular level, we analyzed the relationship between capsular dimensions and expression of CAP genes in the three isolates after 48 of cultivation in either Sabouraud broth or minimal medium. Cultivation of cryptococci in Sabouraud’s medium is known to repress capsule formation, while large capsules are usually formed by cryptococcal cells in minimal medium36. In comparison with the ATCC 24066 isolate, 106.97 and WM 779 cells showed larger capsular diameters after growth in both Sabouraud and minimal media (Fig. 5A). To further explore these differences, we used q-RT-PCR to determine the relative expression of the CAP family of capsule-related genes (CAP59, CAP10, CAP60 and CAP64; Fig. 5B). CAP64 and CAP10 were similarly expressed in all isolates and conditions. On the other hand, expression of CAP59 was reduced in isolate ATCC 24066, in both Sabouraud and minimal media. The same isolate showed enhanced expression of CAP60 under similar conditions (Fig. 5B).


Pathogenic diversity amongst serotype C VGIII and VGIV Cryptococcus gattii isolates.

Rodrigues J, Fonseca FL, Schneider RO, Godinho RM, Firacative C, Maszewska K, Meyer W, Schrank A, Staats C, Kmetzsch L, Vainstein MH, Rodrigues ML - Sci Rep (2015)

Capsular dimensions and expression of CAP genes in C. gattii.A. India ink counter-staining (left panels) and corresponding capsular dimensions (right panels) of C. gattii after growth in Sabouraud or minimal media. Capsular dimensions of the ATCC 24066 isolate were significantly smaller than those observed for 106.97 and WM 779 isolates (***p = <0.0005). Scale bar: 5 μm. B. Expression of CAP genes under the conditions used for determination of capsular dimensions. CAP59 and CAP60 had their expression significantly altered in the ATCC 24066 isolate (***p = <0.0001; **p = <0.005).
© Copyright Policy - open-access
Related In: Results  -  Collection

License
Show All Figures
getmorefigures.php?uid=PMC4495446&req=5

f5: Capsular dimensions and expression of CAP genes in C. gattii.A. India ink counter-staining (left panels) and corresponding capsular dimensions (right panels) of C. gattii after growth in Sabouraud or minimal media. Capsular dimensions of the ATCC 24066 isolate were significantly smaller than those observed for 106.97 and WM 779 isolates (***p = <0.0005). Scale bar: 5 μm. B. Expression of CAP genes under the conditions used for determination of capsular dimensions. CAP59 and CAP60 had their expression significantly altered in the ATCC 24066 isolate (***p = <0.0001; **p = <0.005).
Mentions: Results obtained from serological, morphological and glycosidic composition analyses clearly indicated a high diversity in capsular structures of the herein analyzed C. gattii isolates. To investigate the possibility of additional diversity at the molecular level, we analyzed the relationship between capsular dimensions and expression of CAP genes in the three isolates after 48 of cultivation in either Sabouraud broth or minimal medium. Cultivation of cryptococci in Sabouraud’s medium is known to repress capsule formation, while large capsules are usually formed by cryptococcal cells in minimal medium36. In comparison with the ATCC 24066 isolate, 106.97 and WM 779 cells showed larger capsular diameters after growth in both Sabouraud and minimal media (Fig. 5A). To further explore these differences, we used q-RT-PCR to determine the relative expression of the CAP family of capsule-related genes (CAP59, CAP10, CAP60 and CAP64; Fig. 5B). CAP64 and CAP10 were similarly expressed in all isolates and conditions. On the other hand, expression of CAP59 was reduced in isolate ATCC 24066, in both Sabouraud and minimal media. The same isolate showed enhanced expression of CAP60 under similar conditions (Fig. 5B).

Bottom Line: This great phenotypic diversity reflected in differential pathogenicity.VGIV isolates WM 779 and 106.97 were similar in their ability to cause lethality and produced higher pulmonary fungal burden in a murine model of cryptococcosis, while isolate ATCC 24066 (VGIII) was unable to reach the brain and caused reduced lethality in intranasally infected mice.These results demonstrate a high diversity in the pathogenic potential of isolates of C. gattii belonging to the molecular types VGIII and VGIV.

View Article: PubMed Central - PubMed

Affiliation: Instituto de Microbiologia Paulo de Góes, Federal University of Rio de Janeiro, Rio de Janeiro, Brazil.

ABSTRACT
Cryptococcus gattii is one of the causative agents of human cryptococcosis. Highly virulent strains of serotype B C. gattii have been studied in detail, but little information is available on the pathogenic properties of serotype C isolates. In this study, we analyzed pathogenic determinants in three serotype C C. gattii isolates (106.97, ATCC 24066 and WM 779). Isolate ATCC 24066 (molecular type VGIII) differed from isolates WM 779 and 106.97 (both VGIV) in capsule dimensions, expression of CAP genes, chitooligomer distribution, and induction of host chitinase activity. Isolate WM 779 was more efficient than the others in producing pigments and all three isolates had distinct patterns of reactivity with antibodies to glucuronoxylomannan. This great phenotypic diversity reflected in differential pathogenicity. VGIV isolates WM 779 and 106.97 were similar in their ability to cause lethality and produced higher pulmonary fungal burden in a murine model of cryptococcosis, while isolate ATCC 24066 (VGIII) was unable to reach the brain and caused reduced lethality in intranasally infected mice. These results demonstrate a high diversity in the pathogenic potential of isolates of C. gattii belonging to the molecular types VGIII and VGIV.

No MeSH data available.


Related in: MedlinePlus