Pschunder Bernarda, Locati Lucia, López Oriana, Martin Aispuro Pablo, Zurita Eugenia, Stuible Matthew, Durocher Yves, Hozbor Daniela
Laboratorio Vacunas Salud (VacSal), Instituto de Biotecnología y Biología Molecular (IBBM), Facultad de Ciencias Exactas, Universidad Nacional de La Plata, Centro Científico Tecnológico-Consejo Nacional de Investigaciones Científicas y Técnicas (CCT-CONICET) La Plata, La Plata, Argentina.
Human Health Therapeutics Research Center, National Research Council Canada, Montreal, QC, Canada.
Front Immunol. 2024 Apr 8;15:1387534. doi: 10.3389/fimmu.2024.1387534. eCollection 2024.
For several years, we have been committed to exploring the potential of -derived outer membrane vesicles (OMV) as a promising third-generation vaccine against the reemerging pertussis disease. The results of our preclinical trials not only confirm its protective capacity against infection but also set the stage for forthcoming human clinical trials. This study delves into the examination of OMV as an adjuvant. To accomplish this objective, we implemented a two-dose murine schedule to evaluate the specific immune response induced by formulations containing OMV combined with 3 heterologous immunogens: Tetanus toxoid (T), Diphtheria toxoid (D), and the SARS-CoV-2 Spike protein (S). The specific levels of IgG, IgG1, and IgG2a triggered by the different tested formulations were evaluated using ELISA in dose-response assays for OMV and the immunogens at varying levels. These assays demonstrated that OMV exhibits adjuvant properties even at the low concentration employed (1.5 μg of protein per dose). As this effect was notably enhanced at medium (3 μg) and high concentrations (6 μg), we chose the medium concentration to determine the minimum immunogen dose at which the OMV adjuvant properties are significantly evident. These assays demonstrated that OMV exhibits adjuvant properties even at the lowest concentration tested for each immunogen. In the presence of OMV, specific IgG levels detected for the lowest amount of antigen tested increased by 2.5 to 10 fold compared to those found in animals immunized with formulations containing adjuvant-free antigens (p<0.0001). When assessing the adjuvant properties of OMV compared to the widely recognized adjuvant alum, we detected similar levels of specific IgG against D, T and S for both adjuvants. Experiments with OMVs derived from (OMV) reaffirmed that the adjuvant properties of OMVs extend across different bacterial species. Nonetheless, it's crucial to highlight that OMV notably skewed the immune response towards a Th1 profile (p<0.05). These collective findings emphasize the dual role of OMV as both an adjuvant and modulator of the immune response, positioning it favorably for incorporation into combined vaccine formulations.
几年来，我们一直致力于探索源自[细菌名称]的外膜囊泡（OMV）作为一种有前景的第三代百日咳再发疾病疫苗的潜力。我们的临床前试验结果不仅证实了其对感染的保护能力，也为即将开展的人体临床试验奠定了基础。本研究深入探讨了OMV作为佐剂的情况。为实现这一目标，我们实施了两剂小鼠接种方案，以评估含有OMV与3种异源免疫原组合的制剂诱导的特异性免疫反应：破伤风类毒素（T）、白喉类毒素（D）和严重急性呼吸综合征冠状病毒2刺突蛋白（S）。在剂量反应试验中，使用酶联免疫吸附测定（ELISA）评估不同测试制剂触发的IgG、IgG1和IgG2a的特异性水平，该试验针对不同水平的OMV和免疫原进行。这些试验表明，即使在使用的低浓度（每剂1.5μg蛋白质）下，OMV也表现出佐剂特性。由于这种效应在中等浓度（3μg）和高浓度（6μg）下显著增强，我们选择中等浓度来确定OMV佐剂特性明显显现的最低免疫原剂量。这些试验表明，即使在针对每种免疫原测试的最低浓度下，OMV也表现出佐剂特性。在存在OMV的情况下，与用不含佐剂抗原的制剂免疫的动物相比，检测到的最低测试抗原量的特异性IgG水平增加了2.5至10倍（p<0.0001）。当评估OMV与广泛认可的佐剂明矾相比的佐剂特性时，我们检测到两种佐剂针对D、T和S的特异性IgG水平相似。源自[细菌名称]的OMV（OMV）实验再次证实，OMV的佐剂特性跨越不同细菌种类。尽管如此，必须强调的是，OMV显著使免疫反应偏向Th1型（p<0.05）。这些总体发现强调了OMV作为免疫反应的佐剂和调节剂的双重作用，使其有利于纳入联合疫苗制剂。
