Immune response of Balb C mice against genetic vaccination with Leismania major GP63 gene (lmajgp63)‎

Abstract EN

Leishmania major glycoprotein 63 (lmajgp63) gene was used in this study as DNA vaccine candidates.

Gene was inserted into VR1012 plasmid by using standard molecular biology protocols, resulting in preparation of lmajgp63/VR1012 plasmid.

Vaccine either used as naked or gold particles coated DNA vaccine in immunization of females Balb/c mice.

Animals were immunized at week 0, 2 weeks and 6 weeks.

Dermojet needle free injector had been used to deliver gold particles coated DNA vaccine intradermally (I/D) while ordinary needle injection was used to deliver naked vaccine intramuscularly (I/M).

Immune response for each vaccinated group were detected, two weeks after the third administration of the vaccines, by estimation of serum concentration of IL-2, IL-4, IL-10 and INF-γ, as well as anti-soluble Leismania antigen (anti-SLA) IgG titer, by ELISA test.

The results demonstrated the effectiveness of DNA vaccines in induction immune response comparing to control groups (P<0.05).

The highest serum concentrations of IL-2, INF-γ and anti-SLA IgG OD value observed in mice group which immunized with gold particles coated vaccine injected I/D (182.10 pg/ml, 1699.20 pg/ml and 0.6101 respectively), while the lowest titer was observed in group vaccinated with naked plasmids injected I/M (103.60 pg/ml, 1183.20 pg/ml and 0.3395 respectively).

On the other hand group treated with naked plasmid I/M shows the highest titer of IL-4 and IL-10 concentration (85.30 pg/ml and 53.10 pg/ml respectively), while the lowest titer observed in group injected I/D by gold coated plasmid (50.90 pg/ml and 41.88 pg/ml respectively).

The results also demonstrated that I/D injection of gold particles coated DNA vaccine induced the highest Th1/Th2 response [IL-2/IL-10 (4.348) and INF-γ/IL-4 (33.383)], while I/M injection of naked vaccine gave the lowest results [IL-2/IL-10 (1.951) and INF-γ/IL-4 (13.879)].