Laser-facilitated powder-allergen delivery for epicutaneous immunotherapy

描述(由申请人提供)：这项提案的总体目标是开发一种基于激光的技术，用于微输送粉状过敏原，以实现更安全和更快的皮肤免疫治疗，名为？EPIT。到目前为止，过敏原特异性免疫疗法仍然是对IgE介导的过敏反应长期临床受益的唯一治疗方法，但只有不到5%的患者因为过敏反应和不便的风险而选择这种治疗方法。EPIT可能会缩短治疗时间，降低过敏风险，因为表皮不仅含有丰富的抗原提呈细胞(APC)，而且是一种非血管化组织。不幸的是，通过完整皮肤的表皮传递变应原面临着许多挑战，因为皮肤对大分子是不渗透的，而打破皮肤屏障通常会触发不想要的Th2免疫反应。我们与其他人一起，使用消融性微分数激光(A？FL)在皮肤中产生一系列自我更新的微通道(MC)，用于疫苗输送，并引发强大的Th1免疫反应。这些MC为EPIT提供了独特的优势，因为它们不仅充当粉状过敏原进入表皮的“自由”路径，而且还维持表皮中的过敏原，不断刺激有利于免疫耐受的免疫系统。此外，由于过敏原主要局限于MC内，因此可以很好地预防过敏反应。我们创造了一种简单的方法来制造一种基于粉末的微阵列贴片(PMP)，当应用于激光处理的皮肤上时，这种贴片可以产生高效的表皮递送。我们推测，激光促进的粉状变应原/佐剂的表皮递送可以极大地增强EPIT的疗效，而不会引起过敏反应的风险。我们将用花生蛋白提取物(PPE)和Th1或免疫抑制佐剂制造PMP。通过激光穿孔皮肤的PPE/佐剂的表皮给药将在幼鼠和致敏的C3H/HeJ小鼠以及致敏的新生猪中得到优化(目标1.1)。将在接种现场检测局部先天免疫，并在血样中检测针对花生变应原的体液免疫反应。我们还将研究Th1、Th2和T调节(Treg)细胞，以证实Th1/Treg对过敏原的主导免疫(目标1.2)。最后，我们将在小鼠花生过敏模型中寻找三种剂量的EPIT在治疗花生过敏方面是否优于传统的18剂皮下免疫疗法(目标2)。在工业化国家，免疫球蛋白E介导的过敏症的发生率越来越高。如果成功，这种EPIT将导致花生过敏的更安全和更快的治疗，并可以很容易地扩展到其他由IgE介导的过敏，这将对公共卫生系统产生深远影响。

DESCRIPTION (provided by applicant): The overall objective of this proposal is to develop a laser-based technology for micro-delivering powdered allergens for safer and faster epicutaneous immunotherapy, named ¿EPIT. To date, allergen specific immunotherapy remains the only treatment for long-lasting clinical benefit to IgE-mediated allergies, but fewer than 5% o patients choose the treatment because of a risk of anaphylaxis and inconvenience. EPIT can potentially shorten the duration of the treatment and reduce anaphylactic risk because the epidermis is not only rich in antigen-presenting cells (APCs), but also a non-vascularized tissue. Unfortunately, epidermic delivery of allergen via intact skin faces numerous challenges as the skin is impermeable for macromolecules, whereas breaking skin barrier often triggers unwanted Th2 immune responses. We, along with others, have used ablative micro-fractional laser (A¿FL) to generate an array of self-renewable microchannels (MCs) in the skin for vaccine delivery and to elicit strong Th1 immune responses. These MCs offer unique advantages for EPIT as they not only serve as "free" paths for powdered allergens to enter the epidermis but also sustain the allergen in the epidermis constantly stimulating immune system that favors immune tolerance. Moreover, because the allergen is largely restricted inside the MCs anaphylaxis can be well prevented. We have created a simple way to fabricate a powder-based microarray patch (PMP), which gave rise to efficient epidermic delivery when applied onto laser-treated skin. We hypothesize that the laser-facilitated epidermic ¿-delivery of powdered allergens/adjuvants can greatly augment efficacy of EPIT without incurring a risk of anaphylaxis. We will fabricate PMP with peanut protein extract (PPE), along with Th1 or immunosuppressant adjuvants. Epidermic delivery of PPE/adjuvants via laser-perforated skin will be optimized in naive and sensitized C3H/HeJ mice as well as in sensitized newborn pigs (Aim 1.1). Local innate immunity will be measured at the inoculation site and humoral immune responses against peanut allergens will be assayed in blood samples. We will also investigate Th1, Th2 and T regulatory (Treg) cells to corroborate Th1/Treg-predominant immunity against the allergen (Aim 1.2). Finally, we will seek in a murine peanut allergy model whether three doses of ¿EPIT are superior to conventional 18 doses of subcutaneous immunotherapy in treatment of peanut allergy (Aim 2). IgE-mediated allergy occurs at an increasing rate in industrialized countries. This ¿EPIT, if successful, would result in safer and faster treatments of peanut allergy and can be readily extended to other IgE-mediated allergies, which will have profound impact on public health systems.