Asunto(s)
Equipos y Suministros de Hospitales , Iluminación , Equipo Quirúrgico , Diseño de Equipo , HumanosRESUMEN
A human single-chain Fv (scFv) library as fusion to phage was constructed from donors with a high titer of autoantibodies. The library was subjected to three rounds of positive selection on human melanoma cells and negative selection on human peripheral blood mononuclear cells. Two scFv clones, B3 and B4, were isolated that bound melanoma cells in cell ELISA and fluorescence-activated cell sorting. The scFvs were characterized further by immunohistochemistry on a large number of normal human tissues. No cross-reactivity with normal tissues was observed. On the other hand, the target antigens were expressed in sections from several different melanoma patients and in some breast cancer and basal cell carcinoma sections. The unusually high tumor specificity of the B3 and B4 antigens makes them attractive targets for the specific therapy of melanoma. The selection strategy used should be generally applicable to the identification of novel cell surface antigens by antibody phage display.
Asunto(s)
Anticuerpos Antineoplásicos/aislamiento & purificación , Anticuerpos Antineoplásicos/metabolismo , Melanoma/inmunología , Neoplasias Cutáneas/inmunología , Anticuerpos Antineoplásicos/genética , Especificidad de Anticuerpos/inmunología , Antígenos de Neoplasias/inmunología , Bacteriófagos/genética , Línea Celular , Ensayo de Inmunoadsorción Enzimática , Citometría de Flujo , Técnica del Anticuerpo Fluorescente Indirecta , Humanos , Región Variable de Inmunoglobulina/genética , Región Variable de Inmunoglobulina/metabolismo , Biblioteca de PéptidosRESUMEN
Single-chain antibody fragments (scFvs) have superior pharmacokinetic and biodistribution characteristics compared with larger antibody fragments when used for radioimaging of human tumours. An scFv specific for malignant melanoma (B4 scFv) was tested in a mouse xenograft model for human melanoma and compared with the monoclonal antibody (MAb) LHM2. LHM2 is specific for the high molecular weight proteoglycan melanoma-associated antigen (HMW-MAA), while B4 scFv binds a novel melanoma-specific antigen. The B4 scFv was cleared rapidly from the circulation (t(1/2)alpha = 7 min) compared with LHM2 MAb (t(1/2)alpha = 37 min). However, the B4 scFv had an unusually long t(1/2)beta (437 min compared with 384 min for LHM2 MAb). Biodistribution studies showed that B4 accumulated specifically in the tumour grafts. Although non-specific accumulation in the liver, lung, spleen and blood was lower than with LHM2, non-specific accumulation of B4 in the kidney was higher. Despite this, the overall targeting efficiency in this study, as determined by tumour:normal tissue ratios, showed that B4 was superior to whole antibody. Immunoscintigraphy images showed good correlation with the biodistribution data for B4 and LHM2. This study represents the first use of an anti-melanoma scFv in vivo.
Asunto(s)
Fragmentos de Inmunoglobulinas/inmunología , Melanoma Experimental/inmunología , Animales , Anticuerpos Monoclonales/inmunología , Afinidad de Anticuerpos , Rayos gamma , Humanos , Fragmentos de Inmunoglobulinas/metabolismo , Inmunoterapia , Melanoma Experimental/diagnóstico , Melanoma Experimental/diagnóstico por imagen , Melanoma Experimental/terapia , Tasa de Depuración Metabólica , Ratones , Ratones Endogámicos BALB C , Ratones Desnudos , Trasplante de Neoplasias , Cintigrafía , Distribución Tisular , Células Tumorales CultivadasRESUMEN
We describe a series of six cases exploring the limits of reliability of the dorsal ulnar artery fasciocutaneous flap as described by Becker and Gilbert (1988a; b). Although the territory supplied by the dorsal ulnar artery is 10 cm to 20 cm long by 5 cm to 9 cm wide, Becker and Gilbert suggested that flaps should be confined to smaller dimensions. We have found that larger flaps (15 to 20 cm long and 5 to 8 cm wide) are feasible, extending the use of the flap to the radial side of the wrist and hand. However, problems were encountered with venous drainage and these larger flaps should be used with caution.
Asunto(s)
Mano/cirugía , Colgajos Quirúrgicos , Arteria Cubital , Muñeca/cirugía , Adulto , Anciano , Femenino , Traumatismos de la Mano/cirugía , Humanos , Masculino , Persona de Mediana Edad , Neoplasias Cutáneas/cirugía , Úlcera Cutánea/cirugía , Traumatismos de la Muñeca/cirugíaRESUMEN
A 13-year-old girl of Pakistani origin presented with a non-tender, fluctuant swelling over her left parietal area and an underlying skull defect. At the apex of the swelling there was a sinus. Cultures of the discharge were positive for Mycobacterium tuberculosis. We present a case report of tuberculosis of the skull and review of the literature. We highlight the difficulty which still exists in establishing a diagnosis of tuberculosis in countries where it is uncommon.