carbocyanines and Teratocarcinoma

Here we present the efficiency and versatility of newly developed core-multishell nanoparticles (CMS NPs), to encapsulate and transport the antitumor drugs doxorubicin hydrochloride (Dox), methotrexate (Mtx) and sodium ibandronate (Ibn) as well as dye molecules, i.e., a tetrasulfonated indotricarbocyanine (ITCC) and nile red. Structurally, the CMS NPs are composed of hyperbranched poly(ethylene imine) core functionalized by alkyl diacids connected to monomethyl poly(ethylene glycol). In order to evaluate their transport in aqueous media in vitro, we have used and compared SEC, UV, ITC, and NMR techniques. We observed that the CMS NPs were able to spontaneously encapsulate and transport Dox, Mtx and nile red in both organic and aqueous media as determined by SEC and UV-VIS spectroscopy. For the VIS transparent Ibn Isothermal Titration Calorimetric (ITC) experiments show an exothermic interaction with the CMS NPs. The enthalpic stabilization (DeltaH) upon encapsulation was in the order of approximately 7 kcals/mol which indicates stable interaction between Ibn and nanoparticles. A T(1) inversion recovery NMR experiment was carried out for 31P and 1H nuclei of Ibn and an increment of spin-lattice relaxation time for respective nuclei was observed upon encapsulation. CMS NPs were also found to encapsulate ITCC dye with stoichiometry of 6-8 molecules/nanocarrier. For in vivo imaging studies the dye loaded CMS NPs were injected to F9 teratocarcinoma bearing mice and a strong contrast was observed in the tumor tissues compared to free dye after 6 h of administration.

Topics: Animals; Antineoplastic Agents; Calorimetry; Carbocyanines; Chemistry, Pharmaceutical; Chromatography, Gel; Coloring Agents; Diphosphonates; Doxorubicin; Drug Carriers; Drug Compounding; Ibandronic Acid; Injections, Intravenous; Magnetic Resonance Spectroscopy; Methotrexate; Mice; Nanoparticles; Oxazines; Polyethylene Glycols; Polyethyleneimine; Spectrophotometry, Ultraviolet; Technology, Pharmaceutical; Teratocarcinoma

Optical technologies are evolving in many biomedical areas including the biomedical imaging disciplines. Regarding the absorption properties of physiological molecules in living tissue, the optical window ranging from 700 to 900 nm allows to use fluorescent dyes for novel diagnostic solutions. Here we investigate the potential of two different carbocyanine-based dyes fluorescent in the near infrared as contrast agents for in vivo imaging of subcutaneously grown tumours in laboratory animals. The primary aim was to modify the physicochemical properties of the previously synthesized dye SIDAG to investigate the effect on the in vivo imaging properties.

Topics: Animals; Carbocyanines; Female; Fluorescent Dyes; Infrared Rays; Male; Mice; Mice, Nude; Microscopy, Fluorescence; Molecular Structure; Neoplasm Transplantation; Optics and Photonics; Teratocarcinoma

Monoclonal antibodies to two different targetable antigens were conjugated to each of four commercially available cyanine fluorochromes. Equal amounts of all four antibodies were coinjected into tumor-bearing animals and imaged. Small, superficial tumors were adequately labeled using all four fluorochromes. Large tumors were labeled well only by Cy7, probably due to self-masking and dilution effects. Cy7 was superior to other cyanine fluorochromes for visualizing structures located deep within the animal.

Topics: Animals; Antibodies, Monoclonal; Antigens, Neoplasm; Benzothiazoles; Carbocyanines; Fluorescent Dyes; Humans; Mice; Mice, Inbred BALB C; Nucleolin; Phosphoproteins; RNA-Binding Proteins; Teratocarcinoma; Tumor Cells, Cultured

Far-red-emitting cyanine fluorochromes have many properties desirable for in vivo imaging: absorption and emission at wavelengths where blood and tissue are relatively transparent, high quantum yields, and good solubility even at high molar ratios of fluorochrome to antibody. Potentially, conjugation by multiple linkages should minimize hydrolysis in vivo. We conjugated two tumor-targeting monoclonal antibodies: anti-SSEA-1 (IgM, kappa) at ratios of 1.2-35 mol dye/mol antibody and 9.2.27 (IgG2a, kappa) at 0.6-6 mol dye/mol antibody, using the cyanine fluorochromes Cy3.18, Cy5.18, and Cy5.5.18. Nude mice were inoculated using the SSEA-1-expressing MH-15 teratocarcinoma or the 9.2.27 antigen-expressing SK-MEL-2 melanoma to give tumors at several sites. Conjugated antibody was injected, and mice were imaged immediately after injection and at appropriate intervals thereafter using a standard camera lens, dissecting microscope, or endoscopes. Images were acquired using either an image-intensified video camera or cooled CCD cameras. Immediately after injection, major blood vessels and the heart, liver, and kidneys were readily visualized. After 1 day, tumor-targeting antibody conjugates were concentrated in tumors and there was little circulating conjugate; however, the bladder and kidneys were still visible. Tumors labeled by specific antibody were the most fluorescent tissues at 2 days after injection, but non-specific antibody conjugates did not concentrate in the tumors. The small intestine was weakly visualized by both specific and non-specific antibody conjugates. These data support the possibility of visualizing tumor metastasis by optical means, including currently available endoscopes.

Topics: Animals; Antibodies, Monoclonal; Antibodies, Neoplasm; Antigens, Neoplasm; Carbocyanines; Diagnostic Imaging; Fluorescent Antibody Technique; Humans; Melanoma; Mice; Mice, Inbred BALB C; Mice, Nude; Neoplasms, Experimental; Teratocarcinoma