%0 Journal Article
%T Immune response to Candida albicans Resposta imune a Candida albicans
%A Ivete Conchon Costa
%A Ionice Felipe
%A Luis Carlos Jabur Gaziri
%J Semina : Ci¨ºncias Biol¨®gicas e da Sa¨²de
%D 2008
%I Universidade Estadual de Londrina
%X Candida albicans causes infections of the skin, oral cavity and esophagus, gastrointestinal tract, vagina and vascular system. Most infections occur in immunocompromised hosts or debilitated patients. More than 90% of HIV positive patients suffer from mucosal candidiasis at least once in the course of this disease. The overall severity and chronicity of oral candidiasis in patients with AIDS are mainly attributed to the HIV-induced immune deficiency in the affected individuals, namely, the loss of T-helper cells and reduction in the number of CD4+ T lymphocytes. In mucosal colonization and systemic infections of mice by this fungus, Th1 cells mediate phagocyte-dependent protection, whose most important cytokines are IL-2, IFN- , TNF-¨¢ and IL-12. In contrast, production of inhibitory cytokines such as IL-4 and IL- 10 by Th2 cells are associated with disactivation of phagocytes and disease progression. Possibly, the growth of filamentous forms is better adapted to evade the cells of the immune system, whereas the yeast form may be the mode of proliferation in infected tissues. By the discriminative production of IL- 12 or IL-4 in response to the yeast or filamentous forms respectively, dendritic cells acquire the capacity of inducing the differentiation of CD4+ cells towards the Th1 or Th2 phenotypes. Candida albicans causa infec  es na pele, cavidade oral e es fago, trato gastrointestinal, vagina e sistema vascular de humanos. As infec  es ocorrem em hospedeiros imunocomprometidos ou pacientes debilitados. Acima de 90% dos pacientes HIV+ sofrem de candid¨ªase de mucosas ao menos uma vez no decorrer da doen a. A severidade e cronicidade da candid¨ªase oral em pacientes com AIDS s o atribu¨ªdas, principalmente, ¨¤ imunodefici¨ºncia induzida pelo HIV nos indiv¨ªduos afetados, a saber, perda de fun  es de c¨¦lula T auxiliar e redu  o do n¨²mero de linf¨®citos T CD4. Na coloniza  o de mucosas e infec  es sist¨ºmicas de camundongos por este fungo, c¨¦lulas Th1 medeiam a prote  o dependente de fag¨®citos, cujas citocinas mais importantes s o IL-2, IFN-  e IL-12, TNF-¨¢. Ao contrario, produ  o de citocinas inibidoras tais como, IL-4 e IL-10 por c¨¦lulas Th2 est o associadas ¨¤ desativa  o de fag¨®citos e ¨¤ progress o da doen a. Possivelmente, o crescimento de formas filamentosas est¨¢ melhor adaptado para evadir das c¨¦lulas do sistema imune, enquanto a forma de levedura pode ser o modo de prolifera  o em tecidos infectados. Pela produ  o discriminativa de IL-12 em resposta a levedura e de IL-4 a hifa, as c¨¦lulas dendr¨ªticas adquirem a capacidade para induzir a diferencia  o de c
%K Candida albicans
%K Resposta immune.Infec  s
%K sist¨ºmicas.
%U http://www.uel.br/revistas/uel/index.php/seminabio/article/view/3419