Naslov
Characterisation of novel porphyrin-antibody conjugates for use in photoimmunotherapy of cancer

Autori
Smith, Karen A. ; Pesa, Nela ; Staneloudi, Chrysovalanto ; Swann, Joanne ; Hudson, Robert ; Savoie, Huguette ; Boyle, Ross W. ; Greenman, John

Vrsta, podvrsta i kategorija rada
Sažeci sa skupova, sažetak, znanstveni

Izvornik
Anticancer Research / Delinassios, John G. - Atena : Int. Inst. Anticancer research, 2004, 3637-3638

Skup
7th International Conference of Anticancer Research

Mjesto i datum
Krf, Grčka, 25.10.2004. - 30.10.2004

Vrsta sudjelovanja
Predavanje

Vrsta recenzije
Međunarodna recenzija

Ključne riječi
Photodynamic therapy; Porphyrin; Monoclonal antibodies; Bioconjugation

Sažetak
Photodynamic therapy has become a useful tool in oncology but is often limited by side-effects caused by a lack of targeting of the photosensitiser. This problem can be circumvented by the conjugation of photosensitisers, such as porphyrins, to tumour-specific monoclonal antibodies (mAb). We have developed a simple method for the conjugation of porphyrin isothiocyanate molecules to proteins via the lysine residues. Here a panel of novel porphyrin isothiocyanate molecules were conjugated to a selection of mAb to allow targeted delivery of photosensitiser to tumour cells. Successful conjugation was verified by polyacrylamide gel electrophoresis, which also confirmed no disruption of the antibody after conjugation. Flow cytometry confirmed that there was no change in antibody binding or specificity caused by the conjugation procedure. Cytotoxicity was assesed by MMT assay after incubation of immunoconjugates with carcinoma cell lines and irradiation with non-thermal red light (>600 nm). The porphyrin LD50 concentrations showed that the antibody conjugates were more significantly effective at killing than the drug alone. Further investigation into the mode of cell death revealed that cell death resulted from the rapid onset of apoptosis after irradiation. In addition, confocal microscopy was used to visualise the localisation of the conjugates within the cell. It was shown that porphyrins can be conjugated to antibodies using a simple, widely applicable method that does not affect antibody binding. The lower LD50 concentrations of the bioconjugates, together with minimal non-specific bidning, means that these novel PDT reagents have potential as anti-tumour drugs.

Izvorni jezik
Engleski

Znanstvena područja
Kemija, Biologija, Temeljne medicinske znanosti

POVEZANOST RADA