Data/hora: 06/06/2024 05:23:47

Provedor de dados: | 56
País: | Brazil
Título: | Detection of early apoptosis and cell death in T CD4+ and CD8+ cells from lesions of patients with localized cutaneous leishmaniasis
Autores: | Bertho,A.L.; Santiago,M.A.; Da-Cruz,A.M.; Coutinho,S.G.
Data: | 2000-03-01
Ano: | 2000
Palavras-chave: | Apoptosis; Flow cytometry; Human leishmaniasis; Cell death; T cells.
Resumo: | Human localized cutaneous leishmaniasis (LCL), induced by Leishmania braziliensis, ranges from a clinically mild, self-healing disease with localized cutaneous lesions to severe forms which can present secondary metastatic lesions. The T cell-mediated immune response is extremely important to define the outcome of the disease; however, the underlying mechanisms involved are not fully understood. A flow cytometric analysis of incorporation of 7-amino actinomycin D and CD4+ or CD8+ T cell surface phenotyping was used to determine whether different frequencies of early apoptosis or accidental cell death occur at different stages of LCL lesions. When all cells obtained from a biopsy sample were analyzed, larger numbers of early apoptotic and dead cells were observed in lesions from patients with active disease (mean = 39.5 ± 2.7%) as compared with lesions undergoing spontaneous healing (mean = 17.8 ± 2.2%). Cells displaying normal viability patterns obtained from active LCL lesions showed higher numbers of early apoptotic events among CD8+ than among CD4+ T cells (mean = 28.5 ± 3.8 and 15.3 ± 3.0%, respectively). The higher frequency of cell death events in CD8+ T cells from patients with LCL may be associated with an active form of the disease. In addition, low frequencies of early apoptotic events among the CD8+ T cells were observed in two patients with self-healing lesions. Although the number of patients in the latter group was small, it is possible to speculate that, during the immune response, differences in apoptotic events in CD4+ and CD8+ T cell subsets could be responsible for controlling the CD4/CD8 ratio, thus leading to healing or maintenance of disease.
Tipo: | Info:eu-repo/semantics/article
Idioma: | Inglês
Identificador: | http://www.scielo.br/scielo.php?script=sci_arttext&pid=S0100-879X2000000300010
Editor: | Associação Brasileira de Divulgação Científica
Relação: | 10.1590/S0100-879X2000000300010
Formato: | text/html
Fonte: | Brazilian Journal of Medical and Biological Research  v.33 n.3 2000
Fonte: | info:eu-repo/semantics/openAccess