The Trp-2 AuNVs were calculated to have 24.6 μg of peptide per 1011 particles based on UV–vis absorbance measurements. After subtraction of the standard curves, the conjugation yield was calculated to be approximately 90% (Q-VD-Oph datasheet Additional file 1: Figure S1). Dendritic cell uptake of AuNVs After characterization of the AuNVs, the next step was to evaluate DMXAA manufacturer their interaction with dendritic cells. Using dark-field imaging, the DCs loaded with AuNVs showed significantly more scattering due to the AuNPs compared to untreated DCs with the same imaging exposure (4 ms). The hyperspectral data

showed that the loaded DCs had a spectral shift toward 550 nm, close to the absorbance peak at 529 nm of AuNVs in solution, suggesting that the enhanced scattering was caused by AuNPs (Figure  3). The shift in the peak plasmon resonance wavelength of AuNVs in cells compared to that in solution may be attributed to the higher refractive index within cells and clustering of AuNVs within endosomes or the cytosol. Figure 3 Image and hyperspectral analysis of BMDC loaded AuNVs. (A) Dark-field and hyperspectral images of DCs loaded with AuNVs or DCs only. Only DCs loaded with AuNVs appeared in

selleck the dark-field images with the same exposure time. The hyperspectral images show a spectral shift from purple blue to yellow green when the DCs were loaded with AuNVs (scale bars = 10 um). (B) The average spectral data for BMDCs with or without AuNVs, using each cell as regions of interest. The intensities were calibrated to the lamp spectra baseline. Nanocarrier toxicity GABA Receptor has been a significant limitation for traditional formulations, such as liposomal or polymeric nanocarriers. To evaluate whether the

AuNVs induced cytotoxicity in the DCs, we conducted alamarBlue viability assays using a murine bone marrow-derived dendritic cell line (JAWS II) after incubation with OVA or gp100 AuNVs at various concentrations for 24 h. The fluorescence intensities indicate cellular health and were normalized to the cell control (media only). The viability did not decrease following the addition of AuNVs (ranging from 127% to 155%) when compared to the media-only control (100%) (Additional file 1: Figure S2). Interestingly, the fluorescence intensities for all of the particle-treated JAWS II conditions were significantly higher than the media-only controls (p < 0.0015). alamarBlue measures cellular health by cleavage of the metabolite into fluorescent molecules. Improved metabolic activity may increase the amount of fluorescent by-product. Hence, the results suggest that AuNVs may have caused dendritic cell activation by increasing cellular activity, which can also enhance anti-tumor immune responses.