Your browser doesn't support javascript.
Show: 20 | 50 | 100
Results 1 - 5 de 5
An. bras. dermatol ; 94(1): 52-55, Jan.-Feb. 2019. tab, graf
Article in English | LILACS | ID: biblio-983741


Abstract: Background: Pityriasis rosea is a common papulosquamous disorder. However, its etiology and pathogenesis remain unclear. Objective: We investigate the types of inflammatory cells infiltrating the lesional skin of pityriasis rosea and demonstrate whether T-cell-mediated immunity is involved in the pathogenesis of this condition or not. Methods: The biopsies were taken from the lesional skin of 35 cases of patients diagnosed with pityriasis rosea. The specimens were prepared in paraffin sections, then submitted to routine immunohistochemistry procedures using monoclonal antibodies directed against CD3, CD4, CD8, CD20 and CD45RO and horseradish peroxidase-labeled goat anti-human antibodies. The positive sections were determined by the ratio and staining intensity of positive inflammatory cells. Results: The mean score of positive CD3, CD4, CD8, and CD45RO staining was respectively 3.74±3.88, 5.67±4.40, 2.94±3.42 and 7.68±4.33 in these pityriasis rosea patients (P<0.001). The percentage of positive staining was 54.29% (19/35), 69.7% (23/33), 40% (14/35) and 79.41% (27/34) (P<0.05). However, the staining of CD20 was negative in all samples. The mean score of CD3 staining in patients with time for remission ≤60 days (4.90±4.21) was higher than that in patients with time for remission >60 days (2.00±2.5) (P<0.05), whereas no statistical difference in the mean score of CD4, CD8 and CD45RO staining was observed. study liMitations: The sample size and the selected monoclonal antibody are limited, so the results reflect only part of the cellular immunity in the pathogenesis of pityriasis rosea. Conclusion: Our findings support a predominantly T-cell mediated immunity in the development of pityriasis rosea.

Humans , Male , Female , Adolescent , Adult , Middle Aged , Young Adult , T-Lymphocyte Subsets/pathology , Pityriasis Rosea/pathology , Reference Values , Staining and Labeling , Time Factors , Biopsy , Immunohistochemistry , CD4-Positive T-Lymphocytes/pathology , T-Lymphocyte Subsets/immunology , Pityriasis Rosea/immunology , Leukocyte Common Antigens/analysis , CD3 Complex/analysis , CD8-Positive T-Lymphocytes/pathology , Immunity, Cellular
Arq. neuropsiquiatr ; 74(1): 5-9, Jan. 2016. graf
Article in English | LILACS | ID: lil-772601


The mechanisms involved in the symptoms of Sydenham’s chorea (SC) remain obscure. Taking into account the autoreactive antibody-mediated hypothesis of SC pathogenesis, the persistence of chorea may be associated with increased levels of B1 lymphocytes and other lymphocyte subsets. We evaluated lymphocyte subsets, including B1 and T cells, in patients with remitted (RSC) and persistent (PSC) SC by flow cytometry. Our results showed neither difference in the frequency of T and B lymphocytes subpopulations nor in their activation and functional states. These findings undermine the view of PSC as a sustained cytotoxic cellular-mediated condition. Alternative mechanisms may explain the pathogenesis of PSC.

Os mecanismos subjacentes aos sintomas da coreia de Sydenham (CS) permanecem desconhecidos. Considerando-se a hipótese de que a patogênese da CS é mediada por anticorpos autorreativos, a persistência da coreia está provavelmente associada a níveis aumentados de linfócitos B1 e outros subtipos de linfócitos. No presente trabalho, foram avaliados subtipos de linfócitos B e T em pacientes com CS em remissão (CSR) e persistente (CSP), por citometria de fluxo. Nossos resultados demonstraram que não há diferença na frequência das subpopulações de linfócitos T e B circulantes e no perfil de ativação e estado funcional dessas células. Esses resultados enfraquecem a hipótese de que a CSP seja uma condição imune sustentada mediada por células citotóxicas. São necessários estudos que investiguem mecanismos alternativos que expliquem a patogênese da CSP.

Adolescent , Adult , Female , Humans , Male , Young Adult , Autoimmunity/physiology , B-Lymphocyte Subsets/pathology , Chorea/immunology , T-Lymphocyte Subsets/pathology , B-Lymphocyte Subsets/immunology , Flow Cytometry , Lymphocyte Count , T-Lymphocyte Subsets/immunology
Indian J Dermatol Venereol Leprol ; 2008 Mar-Apr; 74(2): 145-7
Article in English | IMSEAR | ID: sea-52536


Nasal NK/T cell lymphomas are aggressive, locally destructive, midfacial, necrotizing lesions. The nonspecific clinical symptoms constitute a major stumbling block in the early diagnosis and management of these lymphomas. We report here a case of probable nasal NK/T cell lymphoma in an apparently healthy male that progressed rapidly in a short span of time and was managed subsequently with chemotherapy and external beam irradiation with which the lesion regressed.

Aged , Diagnosis, Differential , Granuloma, Lethal Midline/diagnosis , Humans , Killer Cells, Natural/pathology , Lymphoma, T-Cell/diagnosis , Male , Nose Neoplasms/diagnosis , T-Lymphocyte Subsets/pathology
Braz. j. med. biol. res ; 31(1): 77-84, Jan. 1998. ilus, graf
Article in English | LILACS | ID: lil-212541


Cellular immune responses are a critical part of the host's defense against intracellular bacterial infections. Immunity to Brucella abortus crucially depends on antigen-specific T cell-mediated activation of macrophages, which are the major effectors of cell-mediated killing of this organism. T lymphocytes that proliferate in response to B. abortus were characterized for phenotype and cytokine activity. Human, murine, and bovine T lymphocytes exhibited a type 1 cytokine profile, suggesting an analogous immune response in these different hosts. In vivo protection afforded by a particular cell type is dependent on the antigen presented and the mechanism of antigen presentation. Studies using MHC class I and class II knockout mice infected with B. abortus have demonstrated that protective immunity to brucellosis is especially dependent on CD8+ T cells. To target MHC class I presentation we transfected ex vivo a murine macrophage cell line with B. abortus genes and adoptively transferred them to BALB/c mice. These transgenic macrophage clones induced partial protection in mice against experimental brucellosis. Knowing the cells required for protection, vaccines can be designed to activate the protective T cell subset. Lastly, as a new strategy for priming a specific class I-restricted T cell response in vivo, we used genetic immunization by particle bombardment-mediated gene transfer.

Mice , Animals , Bacterial Infections/physiopathology , Cytokines/physiology , In Vitro Techniques , T-Lymphocyte Subsets/pathology , T-Lymphocyte Subsets/physiology