Reproducibility of the new Leishmania vaccine: Changes in T1, T2 and spleen white pulp responses after re- exposure to live promastigote of Leishmania major

Abstract

Introduction: Human leishmaniasis is distributed worldwide and is mainly in the tropics and subtropics, with a prevalence of 12 million cases and an approximately incidence of 0.5 million cases of VL and 1.5 million cases of cutaneous leishmaniasis (CL). Leishmania parasites are vector-born protozoan pathogens found in tropical and subtropical regions of both the old and new world. The disease in human can be divided into cutaneous, visceral, and mucosal syndromes. The aim of this study was more experiments over our previous new formulation leishmania major vaccine which had satisfactory experiments results. Method: For detail procedure refers to author’s previous publications. Briefly, hundred and twenty Balb/cmice were randomly divided into four groups as LT, LB, LBT and control groups. LT, LB and LBT injected subcutaneously with the antigen and the same booster doses with two weeks intervals. The expansion rates of the spleen white pulp size was evaluated using a light microscope and the levels of the serum Th1 (IFN- γ, IL-12) and Th2 (IL-4, IL-10) cytokines measured with the ELISA method. Results: Comparing to the LT and LB groups, the LBT group had highest levels of serum IL12, lowest levels of IL10 and highest increase in the spleen white pulp size. Significant correlation was observed between IL12 and IL10 but not IFN gamma or IL4. Conclusion: present study indicated that the LBT group which received crude cocktail leishmania antigen plus alcoholic extract of Teucrium polium and BCG as adjuvant showed satisfactory cytokines profile comparing to groups LT and LB,since highest levels of IL12 and lower levels of IL10 which could help the infected subjects to inhibit or eradication the intracellular leishmania amastigotes, and also was seen highest increase in the spleen white-pulp size which pointed to the synergistic effects of alcoholic extract of T. polium and BCG.