immunology of infectious and parasitic diseases - XXXVII Congress ...

COMPARISON OF VIRULENCE AND IMMUNE RESPONSE OF DIFFERENT
STRAINS IN EXPERIMENTAL SPOROTRICHOSIS.
JOSÉ ROBERTO FOGAÇA DE ALMEIDA (PG) (1) ; GRASIELLE PEREIRA
JANNUZZI (PG) (1) ; GILBERTO HIDEO KAIHAMI (PG) (2) ; SANDRO ROGERIO
DE ALMEIDA (1).
(1) Department of Clinical and Toxicological Analysis, Faculty of Pharmaceutical
Sciences, University of São Paulo.
(2) Department of Biochemistry, Institute of Chemistry, University of São Paulo.
Introduction and Objects: Sporotrichosis, a disease caused by the dimorphic
fungus Sporothrix schenckii, is a chronic subcutaneous mycosis. In previous
studies the homogenate of organs from mice infected with the strain M-64
produced a mixed Th1/Th2 response, where the serum of infected mice reacted
only with a 70 kDa glycoprotein (GP70) identified as adhesin and as important
virulence factor. More studies are needed on the analysis of the difference of
immune response in others strains of S. schenckii, giving the possibility to
elucidate the relationship between the virulence of the fungus with the immune
response.
Methods and Results: Three groups of 20 BALB/c mice were infected
intraperitoneally with 5x10 6 S. schenckii yeast strain 1099-18 (lymphatic
sporotrichosis-less virulence) and strain 15383 (disseminated sporotrichosismore
virulence), and sterile PBS as negative control. Each 7 days, the spleen
and liver of these animals were taken for evaluation of the infection by CFU and
ELISA. The serum was obtained to perform Western blot using two strains
exoantigens. Infection performed with strain 1099-18 has a decrease on fungal
load in the spleen in the end of the infection time, but in the liver remained
unchanged over time of infection. Cytokine production analyze of the strain
15383, showed a typical Th1 response where was detected high levels of IFN-γ.
In the mice infected with the strain 1099-18 was detected high level of IL-10 and
IL-4 in organs of these animals. In the Western blot accomplished with the
exoantigens by strain 15383 was observed the appearance between 50 kDa
and 70 kDa band from the 14 th day of infection. All Significance test was carried
out by two-way ANOVA Bonferroni post test.