RESUMO
This study was done on four cases of fibrohistiocytic tumors, two benign fibrous histiocytoma and two malignant storiform fibrous histiocytoma. It was believed that growth fraction with Ki 67 increased relatively and respectively with the advanced steps of tumor progression which were generally characterized by an increased growth fraction with neoplastic cell population. This work aimed to study the growth fraction determined with Ki 67 antigen in some fibrohistiocytic lesions
Assuntos
Humanos , Histiocitoma Fibroso Benigno/imunologia , Antígeno Ki-67RESUMO
Tumour necrosis factor (TNF) has been purified from the sera of animals in which the rat histiocytoma AK-5, was rejected spontaneously. Purified TNF-alpha is cytotoxic to AK-5 cells in vitro and the cytotoxic activity of TNF is completely neutralized by anti TNF antiserum. The circulating TNF levels are high by day 10 after the tumour transplantation. Animals which do not regress the tumour have very low levels of TNF in serum. Production of TNF by tumour regressing animals is part of the host immune response to the AK-5 tumour. Also, spleenomegaly in the animals which reject the AK-5 tumour is observed.
Assuntos
Animais , Citotoxicidade Imunológica , Rejeição de Enxerto/imunologia , Histiocitoma Fibroso Benigno/imunologia , Camundongos , Camundongos Endogâmicos BALB C , Transplante de Neoplasias , Ratos , Ratos Wistar , Fator de Necrose Tumoral alfa/isolamento & purificaçãoRESUMO
Status of CD4 and CD8 positive T-lymphocytes, natural killer cells and macrophages has been studied in animals which reject AK-5 histiocytoma. Analysis of immune cells which enter the tumour showed higher number of CD8 positive and NK cells around day 25 after tumour transplantation, suggesting their participation in tumour rejection.
Assuntos
Animais , Histiocitoma Fibroso Benigno/imunologia , Células Matadoras Naturais/imunologia , Linfócitos do Interstício Tumoral/imunologia , Regressão Neoplásica Espontânea/imunologia , Ratos , Ratos Wistar , Baço/imunologiaRESUMO
T lymphocytes from rats with malignant fibrous histiocytoma at different stages of tumor growth were investigated for sensitization to bovine myelin basic protein (MBP). The immunological reactivity was assessed by a leukocyte adherence inhibition assay as an in vitro correlate of celular immunity. We found that only T lymphocytes oobtained 4 and 6 days after tumor transplantation are reactive to MBP (1-2 microng/ml) Since the sequence of the antigenic determinats from MBP is known, our finding may make it possible to select synthetic epitopes for generating cytotoxic T lymphocytes to these tumor cells