It is proposed thatIn this context, the present work was carried out in order to investigate humoral and cellular immune response to brain tissues, in children with West syndrome and its related condidion, the Lennox-Gastaut syndrome. MATERIAL AND METHODSThe test group consisted of 24 children, aged between 4 months and 18 years, whose clinical and eletroencephalographic (EEG) features allowed the diagnosis of West and Lennox-Gastaut syndromes. Twenty healthy children, 12 male and 8 female (age range, 6 months to 8 years) formed the control group. Remarkable clinical characteristics and EEG alterations at the moment of immunological evaluation are detailed in table 1.

-Natural killer (NK) cells play an important role in immune surveillance against tumors. The present work aimed to study the cytotoxic activity of NK cells and T cell subsets in peripheral blood of 13 patients with primary tumors in central nervous system (CNS). As controls 29 healthy subjects with the age range equivalent to the patients were studied. The methods employed were: a) determination of cytotoxic activity of NK cells towards K562 target cells, evaluated by single cell-assay; b) enumeration of CD3+ lymphocytes and their CD4+ and CD8+ subsets defined by monoclonal antibodies; c) the identification of tumors were done by histologic and immunochemistry studies. The results indicated that adults and children with tumor in CNS display reduced percentage of total T cells, helper/inducer subset and low helper/suppressor ratio. The cytotoxic activity of NK cells was decreased in patients with CNS tumors due mainly to a decrease in the proportion of targetbinding lymphocytes. These results suggest that cytotoxic activity of NK cells may be affected by the immunoregulatory disturbances observed in patients with primary tumors in CNS. KEY WORDS: brain tumors, NK cells, T cell subsets.Alterações imunológicas em pacientes com tumores primários no sistema nervoso central RESUMO -As células natural killer (NK) desempenham importante papel na vigilância imunológica contra tumores. O objetivo do presente trabalho foi estudar a atividade citotóxica de células NK e as subpopulações de células T no sangue periférico de 13 pacientes com tumores primários no sistema nervoso central (SNC). Como controle foram estudados 29 indivíduos saudáveis com faixa etária equivalente aos pacientes. Os métodos empregados foram: a) determinação da atividade citotóxica de células NK contra células alvo K562; b) quantificação de linfócitos CD3+ e subpopulações CD4+ e CD8+ por meio de anticorpos monoclonais; c) identificação dos tumores por análise histológica e imuno-histoquímica. Os resultados indicaram que adultos e crianças com tumores no SNC apresentam diminuição na percentagem de linfócitos T, da subpopulação de células T auxiliares e da relação células auxiliares/supressoras. A atividade citotóxica de células NK esteve deprimida em pacientes com tumores devido principalmente à diminuição da capacidade de formar conjugados com a célula alvo K562. Os resultados sugerem que a atividade de células NK pode ser afetada por distúrbios imunorregulatórios observados em pacientes com tumores primários no SNC. PALAVRAS-CHAVE: tumores cerebrais, células NK, subpopulações de células T.Most cancers result from interaction of genetic and environment factors; however, genetic factors by themselves explains only about 5% of all cancer. The others have been atributed to environmental factors, that may interact with genetic cancer susceptibility and individual response 1 .

Depressed natural killer (NK) cell activity has been showed in family members of patients with different types of cancer. The present work aimed to evaluate T cell subsets and NK cell cytotoxic activity in 15 members of a family with high incidence of tumors, such as glioblastoma, gastric, pancreas and colon rectal carcinoma, chronic myelocitic leukemia, melanoma and osteoblastoma. As controls, 19 healthy subjects with the age range equivalent were studied. The enumeration of CD3+ lymphocytes and their CD4+ and CD8+ subsets were defined by monoclonal antibodies and NK cell cytotoxicity towards K562 target cells were evaluated by single cell-assay. The results showed in family members low percentage of total T cells (CD3+), and their CD4+ subset and impairment of CD4/CD8 ratio in relation to control group. All family members presented percentage of NK-target cell conjugate formation bellow the minimum value observed in control group. Thirteen people were examined and followed up during five years, in order to assure that there was no undiagnosed or unsuspected disease at the moment of evaluation. One of them developed osteoblastoma and other malignant melanoma. Two cancer patients, with glioblastoma and chronic myelocytic leukemia were studied during illness. All the corresponding values were comparable. The persistence of low percentage of conjugate formation may be related to a defect on adhesion molecules expression in the surface of NK cells that was probably responsible for the low activity of these cells presented by the family group. Thus, the inheritance mechanism of low adherence of NK cells should have a prognostic value in determining the risk of developing tumors.

-Study objective: : :: : The purpose of this study was to assess the extent of immune dysfunction in a well-defined group of epileptic patients: children with diagnosis of West syndrome (WS) or with transitions to another age-related EEG patterns, the multifocal independent spikes (MIS), and the slow spike-wave complexes (Lennox-Gastaut syndrome -LGS). Thus, WS was studied at different points of the natural evolutive history of the disease. Method: A group of 50 patients (33 with WS, 10 with LGS and 7 with MIS) and 20 age-matched healthy controls were submitted to enumeration of T lymphocyte subsets: CD1, CD3, CD4, CD8, CD4/CD8 ratio and lymphocyte proliferation assay to phytohaemagglutinin (PHA), in the presence of autologous and AB, homologous plasma. Dinitrochlorobenzene (DNCB) skin test sensitization was performed only in patients. Determinations of IgG, IgA, and IgM serum levels were compared to standard values for Brazilian population in different age ranges. Results: Sensitization to DNCB showed absent or low skin reactions in 76% of the patients. High levels of IgG (45.7%) and IgM (61.4%), and lower levels of IgA (23.9%) were detected in the serum of the patients. Enumeration of lymphocyte subsets in peripheral blood showed: low CD3+ (p<0.05), low CD4+ (p<0.05), high CD8+ (p<0.01) and low CD4+ / CD8+ ratio (p<0.001). The proportion of CD1+ cells in the control group was less than 3%, while ranged between 6 and 11 % in 18% of the patients. The in vitro PHA-induced T cell proliferation showed significantly low blastogenic indices only when patients , cells were cultured in presence of their own plasma. No differences in blastogenic indices were observed when the cells of patients and controls were cultured with human AB plasma. Conclusion: The immunodeficiency in WS was mainly characterized by anergy, impaired cell-mediated immunity, altered levels of immunoglobulins, presence of immature thymocytes in peripheral blood and functional impairment of T lymphocytes induced by plasma inhibitory factors.KEY WORDS: dinitrochlorobenzene, West syndrome, Lennox-Gastaut syndrome, multifocal-independent spike syndrome, T-lymphocytes subsets, immunoglobulins, proliferation assay, T cells, CD1, CD3, CD4, CD8.Aspectos imunológicos da síndrome de W Aspectos imunológicos da síndrome de W Aspectos imunológicos da síndrome de W Aspectos imunológicos da síndrome de W Aspectos imunológicos da síndrome de West e evidência de efeitos inibitórios do plasma sobre a função est e evidência de efeitos inibitórios do plasma sobre a função est e evidência de efeitos inibitórios do plasma sobre a função est e evidência de efeitos inibitórios do plasma sobre a função est e evidência de efeitos inibitórios do plasma sobre a função de células T de células T de células T de células T de células T RESUMO -Objetivo: O objetivo deste estudo foi determinar o perfil da deficiência imune em um grupo bem definido de epilepsia: crianças com síndrome de West (SW) e seus padrões EEG de evolução, idade-dependentes, como os complexos onda-agud...