Skin is a highly immunogenic site for vaccine delivery due to its richness of antigen-presenting cells. Several vaccines have been approved for skin delivery and in particular intradermal delivery in the last two decades. Yet intradermal delivery often causes frequent and severe local reactions, preventing the incorporation of adjuvants to further boost skin vaccination. Here we describe a novel skin delivery technology, called micro-fractional epidermal powder delivery or EPD, with minimized local reactions for improved skin vaccination. EPD is based on laser or microneedle treatment to generate microchannel arrays in the epidermis followed by topical application of powder vaccine-coated array patches to deliver vaccines into the skin via microchannels. Due to the fractional delivery, EPD significantly reduces vaccine/adjuvant-induced local reactions without compromising vaccine immunogenicity and adjuvant potency. EPD also eliminates needle injection-associated pain and is promising to improve vaccine stability due to the direct powder delivery. This chapter describes detailed methods for the advantageous EPD in preclinical animal models.

中文翻译：

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用于皮肤疫苗接种的微分数表皮粉末输送。

皮肤由于其抗原呈递细胞的丰富性而成为疫苗接种的高度免疫原性位点。在过去的二十年中，已经批准了几种疫苗用于皮肤递送，尤其是皮内递送。然而，皮内递送通常引起频繁和严重的局部反应，从而阻止了佐剂的掺入以进一步促进皮肤疫苗接种。在这里，我们描述了一种新颖的皮肤递送技术，称为微分数表皮粉末递送或EPD，具有最小化的局部反应，可改善皮肤疫苗接种。EPD基于激光或微针治疗，以在表皮中生成微通道阵列，然后局部应用粉末疫苗涂层的阵列贴片，以通过微通道将疫苗递送到皮肤中。由于分批投放，EPD可显着降低疫苗/佐剂诱导的局部反应，而不会损害疫苗的免疫原性和佐剂效力。EPD还可以消除针头注射相关的疼痛，并且由于直接粉末输送，有望改善疫苗的稳定性。本章介绍在临床前动物模型中有利的EPD的详细方法。