ABSTRACT
In this study, we report on the safety and skin delayed-type hypersensitivity (DTH), responses of the Leishmania donovani whole cell sonicate antigen delivered in conjunction with alum-BCG (AlBCG), Montanide ISA 720 (MISA) or Monophosphoryl lipid A (MPLA) in groups of vervet monkeys. Following three intradermal injections of the inoculums on days 0, 28 and 42, safety and DTH responses were assessed. Preliminary tumor necrosis factor alpha (TNF-α) and interferon gamma (IFN-γ) levels were also measured and these were compared with DTH. Only those animals immunized with alum-BCG reacted adversely to the inoculum by producing ulcerative erythematous skin indurations. Non-parametric analysis of variance followed by a post-test showed significantly higher DTH responses in the MISA+Ag group compared with other immunized groups (p < 0.001). The MPLA+Ag group indicated significantly lower DTH responses to the sonicate antigen compared with the AlBCG+Ag group. There was a significant correlation between the DTH and cytokine responses (p < 0.0001). Based on this study we conclude that Leishmania donovani sonicate antigen containing MISA 720 is safe and is associated with a strong DTH reaction following immunization.
Neste estudo reportamos segurança e resposta de hipersensibilidade tardia (DTH) do antígeno sonicado de células totais de Leishmania donovani introduzidos juntamente com alume-BCG (AIBCG) Montanide ISA 720 (MISA) ou lípide A monofosforilado (MPLA) em grupos de macacos vervet. Depois de três injeções intradérmicas do inóculo nos dias 0, 28 e 42 segurança e resposta DTH foram avaliados. Preliminarmente níveis de fator de necrose tumoral alfa (TNF-α) e interferon gama (IFN-γ) foram também medidos e comparados com o DTH. Somente os animais imunizados com alume-BCG reagiram de maneira diversa ao inóculo produzindo indurações ulceradas e eritematosas na pele. Análise não paramétrica de variação seguida por um teste posterior mostraram resposta significantemente mais alta do DTH no grupo MISA + Ag quando comparado com outros grupos imunizados (p < 0.001). O grupo MPLA + Ag demonstrou resposta DTH significantemente menor do antígeno sonicado comparado com o grupo AIBCG + Ag. Houve correlação significante entre o DTH e a resposta às citocinas (p < 0.0001). Baseados neste estudo concluímos que o antígeno sonicado de Leishmania donovani contendo MISA 720 é seguro e está associado com forte reação DTH após imunização.
Subject(s)
Animals , Female , Male , Adjuvants, Immunologic/administration & dosage , Antigens, Protozoan/administration & dosage , Hypersensitivity, Delayed/immunology , Leishmania donovani/immunology , Leishmaniasis, Visceral/immunology , Lipid A/analogs & derivatives , Adjuvants, Immunologic/adverse effects , Chlorocebus aethiops , Enzyme-Linked Immunosorbent Assay , Interferon-gamma/blood , Lipid A/administration & dosage , Lipid A/adverse effects , Tumor Necrosis Factor-alpha/bloodABSTRACT
Staphylococcal enterotoxin B [SEB] is a potent inducer of cytotoxic T-cell activity, cytokine production and necrosis induction in vivo. Monophosphoryl lipid A [MPL] is an adjuvant derived from the lipopolysaccharide of E.coli, Salmonella Minnesota Re595 and other gram negative bacteria. In this research, The antitumor and antimetastatic effect of intra-venus injection of Monophosphoryl Lipid A [MPL], Staphylococcal enterotoxin B [SEB] and SEB+ MPL was evaluated using Balb/C male mice bearing inoculable mice Fibrosarcoma. The anti tumor effect of SEB+ MPL, SEB and MPL in mice with inoculated fibrosarchoma tumor [Wehi-164] was examined by IV injection and the sizes of the inoculated tumors were determined. The inoculated tumors were also examined histologically. Moreover, histophatologic study in lung tissue didn't showed any metastasis. In the mice IV injected group with SEB4- MPL, reduction of tumor size show a significant difference compared with mice in the SEB and MPL injected and negative control group. A significantly higher frequency of necrosis in tumor tissues was also observed in mice in the IV [SEB+ MPL]-injected group in comparison with other group. Moreover, histophatologic study in lung tissue didn't show any metastasis Our findings suggest that tumor cell death and the prevention of metastasis be caused by increased Cytotoxic T-cell activity in response to IV injection of SEB+ MPL that need to more investigation
Subject(s)
Animals, Laboratory , Male , Lipid A/analogs & derivatives , Staphylococcus aureus , Adjuvants, Immunologic , Fibrosarcoma , Lung Neoplasms , Neoplasm Metastasis/prevention & control , Mice, Inbred BALB CABSTRACT
Tumor immunity is primarily mediated by cells as CD8+ cytotoxic T lymphocytes (CTL) recognize tumor antigen by MHC class I molecules. But most tumors are associated with a decreased expression of MHC class I to escape the antitumor immunity of the host. Our previous data have demonstrated that MPL has an antitumor effect on metastatic lung cancer of B16 melanoma with enhancing cytotoxicity due to increase of IFN-gamma and IL-2, and decrease of IL-4, which indicates the stimulation of type 1 helper T cells (Th1). To determine the effects of MPL, IFN-gamma, TNF-alpha, and IL-1 alpha on MHC class I expression of B16 melanoma cells, we evaluated the expression of MHC class I molecules with treatments of MPL, IFN-gamma, TNF-alpha, and IL-1 alpha by flow cytometry. The supernatant of MPL-treated spleen cells in vitro upregulated the expression of MHC class I molecules of B16 melanoma cells compared to the control supernatant of spleen cells. The MHC class I expression of B16 melanoma cells treated with IFN-gamma, but not TNF-alpha or IL-1 alpha, increased in a time-dependent manner. In conclusion, MPL upregulated MHC class I expression of B16 melanoma cells by activating spleen cells via IFN-gamma. These data suggest that increased IFN-gamma by MPL is responsible for the upregulation of MHC class I expression to augment cytotoxicity. Therefore, we suggest that MPL could play an important role in immunotherapy.