RESUMO
Cell-based therapy for cancer is a promising new field. Among cell types that can be used for this purpose, mesenchymal stem cells (MSCs) appear to hold great advantage for reasons including easier propagation in culture, possible genetic modification to express therapeutic proteins and preferential homing to sites of cancer growth upon in vivo transfer. The present study evaluated the potential of genetically modified MSC, constitutively expressing interferon (IFN)-beta, in an immunocompetent mouse model of prostate cancer lung metastasis. A recombinant adeno-associated virus (rAAV) encoding mouse IFN-beta was constructed and initially tested in vitro for high-level expression and bioactivity of the transgenic protein. MSCs were transduced by the rAAV-IFN-beta or green fluorescent protein ex vivo and used as cellular vehicles to target lung metastasis of TRAMP-C2 prostate cancer cells in a therapy model. Cohorts of mice were killed on days 30 and 75 to determine the effect of therapy by measurement of tumor volume, histology, immunohistochemistry, enzyme-linked immunosorbent assay and flow cytometry. Results indicated a significant reduction in tumor volume in lungs following IFN-beta-expressing MSC therapy. Immunohistochemistry of the lung demonstrated increased tumor cell apoptosis and decreased tumor cell proliferation and blood vessel counts. A significant increase in the natural kill cell activity was observed following IFN-beta therapy correlating the antitumor effect. Systemic level of IFN-beta was not significantly elevated from this targeted cell therapy. These data demonstrate the potential of MSC-based IFN-beta therapy for prostate cancer lung metastasis.
Assuntos
Transferência Adotiva/métodos , Interferon beta/genética , Neoplasias Pulmonares/secundário , Neoplasias Pulmonares/terapia , Células-Tronco Mesenquimais/imunologia , Neoplasias da Próstata/terapia , Animais , Linhagem Celular , Linhagem Celular Tumoral , Movimento Celular , Dependovirus/genética , Expressão Gênica , Terapia Genética/métodos , Vetores Genéticos/administração & dosagem , Vetores Genéticos/genética , Imuno-Histoquímica , Interferon beta/sangue , Interferon beta/imunologia , Células Matadoras Naturais/imunologia , Ativação Linfocitária , Masculino , Transplante de Células-Tronco Mesenquimais/métodos , Células-Tronco Mesenquimais/patologia , Camundongos , Camundongos Endogâmicos C57BL , Neoplasias da Próstata/patologia , Transdução Genética/métodosRESUMO
Immunoglobulin A1 (IgA1) protease, an enzyme that selectively cleaves human IgA1, may be a virulence factor for pathogenic organisms such as Neisseria gonorrhoeae. Host protection from the effects of IgA1 protease includes antibody-mediated inhibition of IgA1 protease activity, and it is believed that the relative balance between IgA1 protease and inhibitory antibodies contributes to the pathogenesis of disease caused by IgA1 protease-producing organisms. We have examined the levels of these two opposing factors in genital tract secretions and sera from women with uncomplicated infection with N. gonorrhoeae. When IgA1 in cervical mucus was examined by Western blotting, no evidence of cleavage fragments characteristic of IgA1 protease activity was seen in gonococcus-infected or control patients. Cleavage fragments typical of IgA1 protease were detected, however, after the addition of exogenous IgA1 protease to cervical mucus. Degraded IgA1 was detected in some vaginal wash samples, but the fragment pattern was not typical of IgA1 protease activity. All N. gonorrhoeae isolates from the infected patients produced IgA1 protease in vitro. All but two serum samples and 16 of 65 cervical mucus samples displayed inhibitory activity against gonococcal IgA1 protease, but there was no significant difference in the level of inhibitory activity between gonococcus-infected and noninfected patients in either cervical mucus or serum. There was no difference in the levels of IgA1 protease-inhibitory activity in serum or cervical mucus collected from patients at recruitment and 2 weeks later. These results suggest that cleavage of IgA1 by gonococcal IgA1 protease within the lumen of the female lower genital tract is unlikely to be a significant factor in the pathogenesis of infections by N. gonorrhoeae.
Assuntos
Genitália Feminina/química , Gonorreia/metabolismo , Imunoglobulina A/metabolismo , Serina Endopeptidases/metabolismo , Inibidores de Serina Proteinase/isolamento & purificação , Adolescente , Adulto , Anticorpos Antibacterianos/análise , Muco do Colo Uterino/química , Muco do Colo Uterino/imunologia , Feminino , Genitália Feminina/imunologia , Gonorreia/imunologia , Humanos , Pessoa de Meia-Idade , Serina Endopeptidases/imunologia , Inibidores de Serina Proteinase/sangue , Vagina/química , Vagina/imunologiaRESUMO
The case of a patient with the new type Bjørk-Shiley aortic and mitral valve prosthesis is described. Three months after implant she suffered acute heart failure and died. Post-mortem examination revealed a fractured outlet strut in the mitral valve prosthesis with dislocation of the disc. The fracture was regarded as due to excessive brittleness caused by demonstrated deposition of chromium-tungsten-carbide.
