The relative importance of CD4+ and CD8+T cells in immunity to pulmonary paracoccidioidomycosis
- 作者：Andressa P. Chiarella ; Celina Arruda ; Adriana Pina ; Tâ ; nia A. Costa ; Rita C.V. Ferreira ; Vera L.G. Calich
- 关键词：Paracoccidioidomycosis ; Fungal infection ; Lung ; T cells ; Cytokines ; T-cell deficient mice ; Scid mice
- 刊名：Microbes and Infection
- 出版年：2007
- 期刊代码：65_12864579
- 类别：imm
- 出版时间：July 2007
- 卷：9
- 期：9
- 页码：1078-1088
- 文件大小：1015 K
摘要
Protective immunity in paracoccidioidomycosis (PCM) is believed to be mediated by cellular immunity, but the role of T cell subsets has never been investigated. The aim of this study was to characterize the function of CD4+ and CD8+ T cells in the immunity developed by susceptible, intermediate and resistant mice after P. brasiliensis infection. In susceptible mice, depletion of CD4+ T cells did not alter disease severity and anergy of cellular immunity but diminished antibody production. Anti-CD8 treatment led to increased fungal loads, but restored DTH reactivity. In resistant mice, both CD4+ and CD8+ T cells control fungal burdens and cytokines although only the former regulate DTH reactions and antibody production. In the intermediate strain, deficiency of whole T and CD8+ T cells but not of CD4+ T or B cells led to increased mortality rates. Thus, in pulmonary PCM: (a) irrespective of the host susceptibility pattern, fungal loads are mainly controlled by CD8+ T cells, whereas antibody production and DTH reactions are regulated by CD4+ T cells; (c) CD4+ T cells play a protective role in the resistant and intermediate mouse strains, whereas in susceptible mice they are deleted or anergic; (d) genetic resistance to PCM is associated with concomitant CD4+ and CD8+ T cell immunity secreting type 1 and type 2 cytokines.