Utilization of LppX protein from Mycobacterium tuberculosis for development of recombinant tuberculosis vaccine

Tuberculosis (TB) is a contagious disease caused by the bacterium Mycobacterium tuberculosis (MTB). Today, BCG is the only vaccine used against TB. However, the protection of this vaccine in adults is insufficient. The purpose of this study was to clone the lppX gene from MTB isolate and to purify recombinant LppX protein for development of recombinant TB vaccine. The lppX gene from MTB strain, isolated from a TB patient in our country, was cloned into first pGEM-T and then pET28a vectors and transferred to E. coli BL21 strain. His-tag recombinant LppX protein expressed in E. coli was purified using nickel columns, and a 7: 3 vaccine formulation was prepared with Montanide ISA 720 VG adjuvant. Vaccine formulation, adjuvant and BCG vaccine, weres. c injected to 5 Balb/c miceand serum samples were collected at regular intervals from mice. The Western blot assay was performed to qualitatively screen the recombinant protein. While bands of the expected size were observed using the recombinant protein and the BCG vaccine-specific serum, the band was not observed only when the adjuvant-specific serum was used. When the IgG values were compared before and after immunization, the vaccine formulationwas significantly increased the humoral immune response. The capacity of these formulations to induce cellular immunity in Balb/c mice was measured by serum interferon-gamma (IFN-γ) and interleukin-12 (IL-12) levels. It was observed that the LppX formulation was as effective as the BCG vaccine in increasing the level of IFN-γ but it was not sufficient to boost IL-12 levels. In future studies, it is thought that double or triple fusions to be formed with different immunogenic proteins may be more effective.