Novel Oral Adjuvant for Dental Vaccines

牙齿和牙龈的细菌感染通常会导致蛀牙和牙周病，但也可能导致严重的全身性疾病，如心内膜炎。疫苗已证明具有预防传染病的潜力。通常需要将抗原与称为“佐剂”的免疫刺激剂共同施用，以刺激保护性免疫的发展，而不是耐受性，特别是对口服抗原的反应。菠萝蛋白酶是从菠萝茎中提取的一种天然的蛋白酶混合物。虽然摄入大多数蛋白质会导致免疫耐受，但我们的初步数据显示，口服菠萝蛋白酶会产生强烈的全身免疫反应。因此，菠萝蛋白酶可以作为诱导抗菠萝蛋白酶抗体的自佐剂。我们的数据表明菠萝蛋白酶通过与广谱蛋白酶抑制剂α -2-巨球蛋白（α - 2m）的复合物捕获而受到抑制。α - 2m复合物被存在于抗原呈递细胞上的受体有效地吸收。我们假设口服具有蛋白水解活性的菠萝蛋白酶在体内与α - 2m相互作用，形成有效诱导免疫反应的复合物。基于这一假设，在α - 2m复合物中与菠萝蛋白酶共捕获的抗原也应该具有很强的免疫原性。本研究的目的是研究菠萝蛋白酶蛋白水解活性在小鼠口腔病原体口服疫苗中诱导针对自身和共同给药抗原的抗体反应中的作用。菠萝蛋白酶的水解活性可以通过抗酸剂的配方来提高，或者通过还原和烷基化来永久灭活。菠萝蛋白酶将与抗原混合或与抗原共价连接的小鼠口服。测定针对菠萝蛋白酶和抗原的特异性血清IgG和唾液IgG和IgA抗体反应。如果这些研究证实了菠萝蛋白酶作为佐剂的潜力，那么含有菠萝蛋白酶和相关抗原混合物的制剂可以被开发出来，作为“嗖嗖和吞咽”疫苗定期给药，以诱导和维持对牙齿病原体的免疫力。

DESCRIPTION: Bacterial infections of the teeth and gingiva commonly cause tooth decay and periodontal disease, but may also cause serious systemic diseases such as endocarditis. Vaccines have a demonstrated potential to prevent infectious diseases. Co-administration of antigen with an immune stimulant called an "adjuvant" is usually necessary to stimulate the development of protective immunity rather than tolerance, particularly in response to oral antigens. Bromelain is a natural mixture of proteinases derived from pineapple stem. Although ingestion of most proteins results in immune tolerance, our preliminary data show that bromelain generates strong systemic immune responses when administered orally. Thus bromelain may serve as a self-adjuvant for induction of anti-bromelain antibodies. Our data show that bromelain is inhibited by trapping in complexes with the broad spectrum proteinase inhibitor alpha-2-macroglobulin (alpha-2M). Alpha-2M complexes are efficiently taken up by receptors that are present on antigen-presenting cells. We posit that proteolytically active bromelain given orally interacts with alpha-2M in vivo to form complexes that efficiently induce immune responses. Based upon this hypothesis, antigens co-trapped with bromelain in alpha-2M complexes should also be strongly immunogenic. The Aim of this study is to investigate the role of bromelain proteolytic activity in induction of antibody responses against itself and co-administered antigens, using an oral vaccine against Dental pathogens in mice. Bromelain proteolytic activity will be increased by formulation in antacid or permanently inactivated by reduction and alkylation. Bromelain will be administered orally to mice mixed with or covalently linked to antigen. Specific serum IgG and salivary IgG and IgA antibody responses against bromelain and antigen will be determined. If these studies confirm the potential of bromelain as an adjuvant, preparations containing bromelain and a mixture of relevant antigens could be developed for periodic administration as "swish and swallow" vaccines to induce and maintain immunity against Dental pathogens.