Cutaneous leishmaniasis in Syria is caused mainly by Leishmania tropica. It represents a serious health problem, which has aggravated further after the civil war in the country. Until now, there are no effective protective strategies, safe
therapy, or efficacious
vaccine to protect from this
infection.
DNA vaccines represent a promising approach for achieving protection against
leishmaniasis. The L5
ribosomal protein plays fundamental roles in the assembly process of the ribosome subunits, so this study has chosen the
ribosomal protein L5 gene to design
a DNA vaccine against Leishmania tropica
infection. After proving the existence of the
ribosomal protein L5 gene in a Syrian strain of Leishmania tropica (LCED Syrian 01), it was sequenced and cloned into a pCI plasmid, and the designed
DNA vaccine was administered to BALB/c mice. The protective response was evaluated by measuring lesion development in immunized BALB/c mice for 6 weeks after challenging mice with the parasite. RT-qPCR was used to quantify
IL-12, IFN-γ, and
IL-4 in draining lymph nodes (DLNs) of immunized mice. In the final week, the parasite burden was determined in footpad lesions and local draining lymph nodes (DLNs). This study demonstrated the presence and expression of the
ribosomal protein L5 gene in the Syrian strain of Leishmania tropica promastigotes. The sequence of the
ribosomal protein cDNA L5 gene was determined and published in Genbank. The gene size was 918 bp. Expression was also demonstrated at the level of
cDNA. This study also demonstrated that vaccination with the
ribosomal protein L5 gene induces TH1 response in immunized mice. This response prevents the partial development of a skin lesion of Leishmania.