Tehran University of Medical Sciences Iranian Journal of Microbiology 2008-3289 12 5 2020 10 31 417 423 Ava Behrouzi Department of Mycobacteriology and Pulmonary Research, Pasteur Institute of Iran, Tehran, Iran Reza Arabi Mianroodi Department of R&D, Research and Production Complex, Pasteur Institute of Iran, Tehran, Iran Parviz Afrough Department of Mycobacteriology and Pulmonary Research, Pasteur Institute of Iran, Tehran, Iran Ahmad Ayadi Department of Mycobacteriology and Pulmonary Research, Pasteur Institute of Iran, Tehran, Iran Amirarsalan Serajian Department of Health Education, ACECR, Khuzestan, Ahvaz, Iran 2019 03 02 2020 10 31 Background and Objectives: Nontypeable Haemophilus influenzae (NTHi) are major causes of non-invasive infections, including otitis media and sinusitis and it can also contribute to respiratory infections of all ages. Currently, there is no licensed vaccine against NTHi commercially available. Many studies have been conducted on the use of OMV as a vaccine against NTHi. The purpose of this study is to achieve an immunogenic vaccine against NTHi. Materials and Methods: In this study, standard OMV Haemophilus (ATCC49766) with adjuncts CpG and MPLA was used and after infusion into BALB/c mice, the levels of antibodies and cytokines were measured on serum of immunized mice. Results: The results showed that total IgG antibody and IgG1 and IgG2a isotypes in OMV immunized mice with mixture of CpG-MPLA adjuvant had a significant increase. Also, the results of cytokines (IL-10, IL-4 and IFN-γ) showed that IL-4 had the highest rate. Conclusion: These findings indicate that OMVs derived from NTHi strains have a high potential to act as a vaccine against NTHi infections. https://ijm.tums.ac.ir/index.php/ijm/article/view/2049 https://ijm.tums.ac.ir/index.php/ijm/article/download/2049/1276