The 'Nanopatch' (NP) comprises arrays of densely packed projections with a defined geometry and distribution designed to physically target vaccines directly to thousands of epidermal and dermal antigen presenting cells (APCs). These miniaturized arrays are two orders of magnitude smaller than standard needles-which deliver most vaccines-and are also much smaller than current microneedle arrays. The NP is dry-coated with antigen, adjuvant, and/or DNA payloads. After the NP was pressed onto mouse skin, a protein payload co-localized with 91.4 + or - 4.1 APC mm(-2) (or 2925 in total) representing 52% of the delivery sites within the NP contact area, agreeing well with a probability-based model used to guide the device design; it then substantially increases as the antigen diffuses in the skin to many more cells. APC co-localizing with protein payloads rapidly disappears from the application area, suggesting APC migration. The NP also delivers DNA payloads leading to cutaneous expression of encoded proteins within 24 h. The efficiency of NP immunization is demonstrated using an inactivated whole chikungunya virus vaccine and a DNA-delivered attenuated West Nile virus vaccine. The NP thus offers a needle-free, versatile, highly effective vaccine delivery system that is potentially inexpensive and simple to use.

Chemically synthesized combinatorial libraries of unmodified or modified nucleic acids have not previously been used in methods to rapidly select oligonucleotides binding to target biomolecules such as proteins. Phosphorothioate oligonucleotides (S-ODNs) or phosphorodithioate oligonucleotides (S2-ODNs) with sulfurs replacing one or both of the non-bridging phosphate oxygens bind to proteins more tightly than unmodified oligonucleotides and have the potential to be used as diagnostic reagents and therapeutics. We have applied a split synthesis methodology to create one-bead one-S-ODN and one-bead one-S2-ODN libraries. Binding and selection of specific beads to the transcription factor NF-kappaB p50/p50 protein were demonstrated. Sequencing both the nucleic acid bases and the positions of any 3'-O-thioate/dithioate linkages was carried out by using a novel PCR-based identification tag of the selected beads. This approach allows us to rapidly and conveniently identify S-ODNs or S2-ODNs that bind to proteins.

An immunofluorescence assay was developed to identify proteins specifically binding to oligonucleoside phosphorodithioate (ODN) aptamers from a bead-bound ODN library. Accordingly, NF-kappaB p50 protein was incubated with either bead-bound NF-kappaB consensus sequence or a bead-bound ODN combinatorial library and adsorption was then assessed using a specific primary antibody and a secondary antibody conjugated with Alexa 488 fluorescent dye. This assay avoids any problems related to fluorescently labeling target proteins. The method is straightforward and readily applicable to other transcription factors and proteins, and the feasibility of its application for high-throughput screening of large aptamer bead-based libraries by flow cytometry is demonstrated.

We describe the development of a sub-millimetre skin punch biopsy device for painless and suture-free skin sampling for molecular diagnosis and research. Conventional skin punch biopsies range from 2-4 mm in diameter. Local anaesthesia is required and sutures are usually used to close the wound. Our microbiopsy is 0.50 mm wide and 0.20 mm thick. The microbiopsy device is fabricated from three stacked medical grade stainless steel plates tapered to a point and contains a chamber within the centre plate to collect the skin sample. We observed that the application of this device resulted in a 0.21 ± 0.04 mm wide puncture site in volunteer skin using reflectance confocal microscopy. Histological sections from microbiopsied skin revealed 0.22 ± 0.12 mm wide and 0.26 ± 0.09 mm deep puncture sites. Longitudinal observation in microbiopsied volunteers showed that the wound closed within 1 day and was not visible after 7 days. Reflectance confocal microscope images from these same sites showed the formation of a tiny crust that resolved by 3 weeks and was completely undetectable by the naked eye. The design parameters of the device were optimised for molecular analysis using sampled DNA mass as the primary end point in volunteer studies. Finally, total RNA was characterized. The optimised device extracted 5.9 ± 3.4 ng DNA and 9.0 ± 10.1 ng RNA. We foresee that minimally invasive molecular sampling will play an increasingly significant role in diagnostic dermatology and skin research.

In vivo reflectance confocal microscopy (RCM) is a relatively novel non-invasive tool for microscopic evaluation of the skin used prevalently for diagnosis and management of skin tumour. Its axial resolution, its non-invasive and easy clinical application represents the goals for a large diffusion of this technique. During the last 15 years, RCM has been demonstrated to be able to increase the sensibility and sensitivity of dermoscopy in the diagnosis of skin tumours integrating in real time clinic, dermoscopic and microscopic information useful for the definition of malignancy. Despite to date, no large comparative studies on inflammatory skin diseases has been published in the literature, several papers already showed that RCM has a potential for the evaluation of the descriptive features of the most common inflammatory skin diseases as psoriasis, lupus erythematosus, contact dermatitis and others. The aim of the application of this technique in non-neoplastic skin diseases has been prevalently focused on the possibility of clinical diagnosis confirmation, as well as therapeutic management. Moreover, the use of RCM as driver for an optimised skin biopsy has been also followed in order to reduce the number of unsuccessful histopathological examination. In this review article we describe the confocal features of the major groups of inflammatory skin disorders focusing on psoriasiform dermatitis, interface dermatitis and spongiotic dermatitis.

Reflectance confocal microscopy (RCM) is a powerful tool for in-vivo examination of a variety of skin diseases. However, current use of RCM depends on qualitative examination by a human expert to look for specific features in the different strata of the skin. Developing approaches to quantify features in RCM imagery requires an automated understanding of what anatomical strata is present in a given en-face section. This work presents an automated approach using a bag of features approach to represent en-face sections and a logistic regression classifier to classify sections into one of four classes (stratum corneum, viable epidermis, dermal-epidermal junction and papillary dermis). This approach was developed and tested using a dataset of 308 depth stacks from 54 volunteers in two age groups (20-30 and 50-70 years of age). The classification accuracy on the test set was 85.6%. The mean absolute error in determining the interface depth for each of the stratum corneum/viable epidermis, viable epidermis/dermal-epidermal junction and dermal-epidermal junction/papillary dermis interfaces were 3.1

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