通过在明矾/纳洛酮佐剂中配制来提高灭活新冠病毒疫苗效力；强大的T细胞和抗受体结合域IgG反应

Improvement of the inactivated SARS-CoV-2 vaccine potency through formulation in alum/naloxone adjuvant; Robust T cell and anti-RBD IgG responses.

作者信息

Haghighi Melika, Khorasani Akbar, Karimi Pegah, Mahdavi Mehdi

机构信息

Advanced Therapy Medicinal Product (ATMP) Department, Breast Cancer Research Center, Motamed Cancer Institute, Academic Center for Education, Culture and Research (ACECR), Tehran, Iran.

Recombinant Vaccine Research Center, Tehran University of Medical Sciences, Tehran, Iran.

出版信息

Iran J Basic Med Sci. 2022 May;25(5):554-561. doi: 10.22038/IJBMS.2022.63527.14015.

OBJECTIVES

SARS-CoV-2, emerging as a major threat to public health, has to be controlled through vaccination. Naloxone (NLX), an opioid receptor antagonist, demonstrated its adjuvant activity for microbial vaccines. In this study, inactivated SARS-CoV-2 was developed in the Alum/NLX adjuvant to increase the potency of the inactivated SARS-CoV-2 vaccine.

MATERIALS AND METHODS

BALB/c mice were immunized on days 0 and 14 with inactivated SARS-CoV-2-Alum, -Alum + NLX 3 mg/kg, -Alum + NLX 10 mg/kg, and -Freund adjuvant, as well as PBS. IFN-γ and IL-4 cytokines and Granzyme-B release were assessed with ELISA. In addition, specific total IgG, IgG1/IgG2a isotypes, and ratio as well as anti-RBD IgG responses were assessed with an optimized ELISA.

RESULTS

SARS-CoV-2-Alum-NLX10 group showed a significant increase in the IFN-γ cytokine response versus SARS-CoV-2-Alum, SARS-CoV-2-Alum-NLX3, and PBS groups. The SARS-CoV-2-Alum-NLX3 group exhibited a significant decrease in IL-4 cytokine versus SARS-CoV-2-Alum. The mice immunized with SARS-CoV-2-Alum-NLX10 showed a significant increase in CTL activity versus SARS-CoV-2-Alum and PBS. In addition, mice immunized with SARS-CoV-2-Alum-NLX3, SARS-CoV-2-Alum-NLX10 and SARS-CoV-2-Freund demonstrated an increase in IgG response, as compared with SARS-CoV-2-Alum and PBS group. Furthermore, all formulations of SARS-CoV-2 vaccines could induce both IgG1 and IgG2a isotypes. But, the IgG2a/IgG1 ratio in SARS-CoV-2-Freund and SARS-CoV-2-Alum-NLX10 revealed an increase as compared with that of the SARS-CoV-2-Alum group. Anti-RBD IgG response in the SARS-CoV-2-Alum-NLX10 group showed a significant increase as compared with the Alum-based vaccine.

CONCLUSION

Formulation of inactivated SARS-CoV-2 virus in NLX/alum adjuvant improved the potency of humoral and, especially, cellular responses.

目的

严重急性呼吸综合征冠状病毒2（SARS-CoV-2）已成为对公众健康的重大威胁，必须通过接种疫苗来加以控制。纳洛酮（NLX）作为一种阿片受体拮抗剂，已证明其对微生物疫苗具有佐剂活性。在本研究中，在铝盐/纳洛酮佐剂中制备了灭活的SARS-CoV-2，以提高灭活SARS-CoV-2疫苗的效力。

材料与方法

在第0天和第14天，用灭活的SARS-CoV-2-铝盐、铝盐+3mg/kg纳洛酮、铝盐+10mg/kg纳洛酮、弗氏佐剂以及磷酸盐缓冲液（PBS）对BALB/c小鼠进行免疫接种。采用酶联免疫吸附测定（ELISA）法评估干扰素-γ（IFN-γ）、白细胞介素-4（IL-4）细胞因子以及颗粒酶B的释放情况。此外，还采用优化的ELISA法评估特异性总免疫球蛋白G（IgG）、IgG1/IgG2a亚型及其比例以及抗受体结合域（RBD）IgG反应。

结果

与SARS-CoV-2-铝盐组、SARS-CoV-2-铝盐-NLX3组和PBS组相比，SARS-CoV-2-铝盐-NLX10组的IFN-γ细胞因子反应显著增加。与SARS-CoV-2-铝盐组相比，SARS-CoV-2-铝盐-NLX3组的IL-4细胞因子显著减少。与SARS-CoV-2-铝盐组和PBS组相比，用SARS-CoV-2-铝盐-NLX10免疫的小鼠的细胞毒性T淋巴细胞（CTL）活性显著增加。此外，与SARS-CoV-2-铝盐组和PBS组相比，用SARS-CoV-2-铝盐-NLX3、SARS-CoV-2-铝盐-NLX10和SARS-CoV-2-弗氏佐剂免疫的小鼠的IgG反应有所增加。此外，所有SARS-CoV-2疫苗制剂均可诱导IgG1和IgG2a亚型产生。但是，与SARS-CoV-2-铝盐组相比，SARS-CoV-2-弗氏佐剂组和SARS-CoV-2-铝盐-NLX10组的IgG2a/IgG1比例有所增加。与基于铝盐的疫苗相比，SARS-CoV-2-铝盐-NLX10组的抗RBD IgG反应显著增加。