RESUMO
Different spleen and tumor cell factors modifying tumoral and metastatic growth were studied. Spleen cell culture supernatants (SCS) from small and large tumor-bearing mice enhanced tumor growth. After tumor surgery, tumor enhancement was only mediated by supernatants from large tumor resected mice. Tumor facilitation and angiogenic response were mediated by the same supernatants; different fractions for these two activities were characterized. T and non-T cells, depending on tumor burden, were responsible for the enhancing activity; but angiogenesis depended only on T cells. While augmentation of metastatic spread was produced by tumor antigens (soluble tumor extracts, tumor-cell supernatants, formolized tumor cells), primary tumor development was not modified by tumor-cell supernatants. Increased incidence of metastases was also mediated by SCS from tumor resected mice which had previously been inoculated with tumor antigens. Immune status of tumor-resected mice was evaluated by delayed-type hypersensitivity reaction. Tumor cell membranes enriched with cholesterol-hemisuccinate were able to increase anti-tumor immune response.
Assuntos
Adenocarcinoma/imunologia , Neoplasias Mamárias Experimentais/imunologia , Adenocarcinoma/patologia , Adenocarcinoma/secundário , Animais , Antígenos de Neoplasias/imunologia , Membrana Celular/efeitos dos fármacos , Ésteres do Colesterol/farmacologia , Linfócitos/fisiologia , Neoplasias Mamárias Experimentais/patologia , Neoplasias Mamárias Experimentais/secundário , Camundongos , Metástase Neoplásica , Baço/patologiaRESUMO
Different spleen and tumor cell factors modifying tumoral and metastatic growth were studied. Spleen cell culture supernatants (SCS) from small and large tumor-bearing mice enhanced tumor growth. After tumor surgery, tumor enhancement was only mediated by supernatants from large tumor resected mice. Tumor facilitation and angiogenic response were mediated by the same supernatants; different fractions for these two activities were characterized. T and non-T cells, depending on tumor burden, were responsible for the enhancing activity; but angiogenesis depended only on T cells. While augmentation of metastatic spread was produced by tumor antigens (soluble tumor extracts, tumor-cell supernatants, formolized tumor cells), primary tumor development was not modified by tumor-cell supernatants. Increased incidence of metastases was also mediated by SCS from tumor resected mice which had previously been inoculated with tumor antigens. Immune status of tumor-resected mice was evaluated by delayed-type hypersensitivity reaction. Tumor cell membranes enriched with cholesterol-hemisuccinate were able to increase anti-tumor immune response.
RESUMO
The interferon induction by Rous sarcoma DNA in an homologous culture system and a further insight of its kinetics and antimetabolites action were the principal aim of the present study. There was a direct relation between the dose of the inducer and the protection against the cytoplathogenic effect of the challenging virus (VSV) reaching the highest activity (68-75% CPE inhibition) with 100 mug RS-DNA. The kinetics of the induction revealed a peak inhibition by 18 hours after the inducer. Treatment with Actinomycin D evidenced that both interferon production and activity are modified. Its early addition resulted in a poor protection; but an accentuated interferon release was observed when antimetabolite was added 18 hours after the inducer. Similar results were obtained when its effect was studied on the activity of exogenous interferon. Interferon induction by Rous sarcoma DNA in an homologous system, allows the detection of a difference between tumoral and normal DNA at a biological level.
