Aseptic cure of pulmonary paracoccidioidomycosis can be achieved after a previous subcutaneous immunization of susceptible but not resistant mice.
The murine model of paracoccidioidomycosis, the most important South American endemic mycosis, mimics the human disease: resistance is associated with preserved cellular immunity while T-cell anergy is related with susceptibility. In the present study we asked whether a previous s.c. infection which induces strong cellular immunity would protect mice against a lethal pulmonary challenge. It was found that susceptible but not resistant mice developed immunoprotection and aseptic cure of infection. Immunoprotection led to reversal of DTH anergy, increased levels of antibodies and pulmonary IL-12, IL-2 and IL-4 indicating a balanced type 1/type 2 response. On the contrary, no marked differences in A/Sn infection and immunity were observed. Depletion experiments showed that immunoprotection required the cooperative action of CD4(+) and CD8(+) T cells in association with IFN-gamma and IL-12. Altogether, these observations demonstrated that susceptible hosts can develop sterilizing immunity and defined the main immunological requirements to control secondary paracoccidioidomycosis.
Arruda
Celina
C
Departamento de Imunologia, Instituto de Ciências Biomédicas da Universidade de São Paulo, Av. Prof. Lineu Prestes 1730, CEP 05508-900 São Paulo, SP, Brazil.
Vaz
Celidéia A C
CA
Calich
Vera L G
VL
D000818:Animals; D000908:Antibodies, Fungal / Q000097:blood; D015496:CD4-Positive T-Lymphocytes / Q000276:immunology; D018414:CD8-Positive T-Lymphocytes / Q000276:immunology; D004198:Disease Susceptibility / Q000276:immunology; D005657:Fungal Vaccines / Q000008:administration & dosage*; D020022:Genetic Predisposition to Disease; D006968:Hypersensitivity, Delayed; D007114:Immunization; D007279:Injections, Subcutaneous; D007371:Interferon-gamma / Q000276:immunology; D007378:Interleukins / Q000276:immunology; D008168:Lung / Q000276:immunology; D008172:Lung Diseases, Fungal / Q000097:blood / Q000235:genetics* / Q000276:immunology / Q000517:prevention & control*; D008297:Male; D051379:Mice; D010228:Paracoccidioides / Q000276:immunology*; D010229:Paracoccidioidomycosis / Q000097:blood / Q000235:genetics* / Q000276:immunology / Q000517:prevention & control*; D016176:T-Lymphocyte Subsets
D000908:Antibodies, Fungal; D005657:Fungal Vaccines; D007378:Interleukins; D007371:Interferon-gamma