Poorly soluble
photosensitizer, meso-
tetraphenylporphine (TPP), was solubilized using the polymeric
micelles prepared from
polyethylene glycol-phosphatidyl
ethanolamine conjugate (
PEG-PE). TPP-loaded
PEG-PE micelles have been additionally modified with
tumor-specific monoclonal 2C5 antibody (mAb 2C5), which resulted in significantly improved anticancer effect of the
drug under the
PDT conditions against murine
Lewis lung carcinoma (LLC) In vivo in female C57BL/6 mice. Fourteen days after
tumor inoculation, the mice with more than 2 mm diameter
tumors were given an
intravenous injection of 1 mg/kg of free TPP or TPP loaded into control
PEG-PE micelles or into mAb 2C5-PEG-PE
tumor-targeted immunomicelles. Twenty-four hours after the administration, the animals were anesthetized, and
tumor sites were illuminated with light (630 nm) for 12 min. Microscopic evaluation of
tumor response was conducted in some mice 24 h after light irradiation, and
tumor size was followed in the remaining animals for another 35 days. The attachment of mAb 2C5 to TPP-loaded immunomicelles provided the maximum level of
tumor growth inhibition. Enhanced
tumor accumulation of TPP-loaded mAb 2C5-PEG-PE-immunomicelles was confirmed by gamma-imaging studies. The modification of the TPP-loaded polymeric
micelles with
tumor-specific
antibodies could be used as a general approach to enhance the efficacy of
PDT.