The effects of CpG-ODNs and Chitosan adjuvants on the elicitation of immune responses induced by the HIV-1-Tat-based candidate vaccines in mice

• Published in: Pathogens and disease 2017-03, Vol.75 (2)
• Main Authors: Alipour, Samira, Mahdavi, Atiyeh, Abdoli, Asghar
• Format: Article
• Language: English
• Subjects: Acquired immune deficiency syndrome; Adjuvants; Adjuvants, Immunologic; AIDS; AIDS Vaccines - immunology; Alum; Aluminum sulfate; Animals; Cell-mediated immunity; Chitosan; Chitosan - immunology; CpG islands; Cytotoxicity, Immunologic; Disease Models, Animal; Female; Formulations; HIV; HIV Antibodies - blood; HIV Antibodies - immunology; HIV Infections - immunology; HIV Infections - prevention & control; HIV-1 - immunology; Human immunodeficiency virus; Humoral immunity; Immune response (humoral); Immunity; Immunization; Immunogenicity; Interferon-gamma - biosynthesis; Lymphocyte Activation; Lymphocytes - immunology; Lymphocytes - metabolism; Lymphocytes T; Mice; Oligodeoxyribonucleotides - immunology; Proteins; Recombinant Proteins - immunology; T cell receptors; tat Gene Products, Human Immunodeficiency Virus - immunology; Tat protein; Vaccines
• ISSN: 2049-632X; 2049-632X
• DOI: 10.1093/femspd/ftx013

Abstract HIV1-Tat-based vaccines could elicit broad, durable and neutralizing immune responses and are considered as potential AIDS vaccines. The present study aims to formulate CpG-ODNs adjuvant and Chitosan with Tat protein to enhance the immunogenicity of HIV-1-Tat-based candidate vaccines and to investigate their efficacies in mice. To this end, we added CpG-ODNs, Chitosan and Alum as adjuvants to the Tat-based candidate vaccine formulations. Then, we compared frequency and magnitude of both humoral and cellular immune responses from mice immunized with the adjuvant-formulated Tat candidate vaccines against those obtained from mice immunized with recombinant Tat protein alone. Mice were subcutaneously immunized three times at 2-week intervals with the candidate vaccines. Measurements of anti-Tat immune responses showed that all vaccinated groups had a good immunity compared to the control groups and developed high levels of both humoral and cellular responses. However, immunized mice with CpG-ODNs, and Chitosan-adjuvanted Tat vaccines elicited stronger T-cell responses (both humoral and cellular immunity) compared to the others. These data suggest that co-administration of recombinant Tat protein with CpG-ODNs and Chitosan may serve as a potential formulation for enhancing of the Tat vaccine-induced immunity and might have effects on shaping Th polarization induced by HIV1-Tat protein vaccines. Immunized mice with CpG-ODNs, and Chitosan-adjuvanted Tat vaccines elicited stronger T-cell responses (both humoral and cellular immunity) compared to mice immunized with Alum-adjuvanted Tat and recombinant Tat protein alone.