Oral vaccination of mice against rodent malaria with recombinantLactococcus lactisexpressing MSP-1₁₉

[[[ Aim: ]]] To construct the recombinant Lactococcus lactis as oral delivery vaccination against malaria. [[[ Methods: ]]] The C-terminal 19-ku fragments of MSP1 (MSP-1(19)) of Plasmodium yoelii 265-BY was expressed in L. lactis and the recombinant L. lactis was administered orally to BALB/c and C57BL/6 mice. After seven interval vaccinations within 4 wk, the mice were challenged with P. yoelii 265-BY parasites of erythrocytic stage. The protective efficacy of recombinant L. lactis was evaluated. [[[ Results: ]]] The peak parasitemias in average for the experiment groups of BALB/c and C57BL/6 mice were 0.8+/-0.4% and 20.8+/-26.5%, respectively, and those of their control groups were 12.0+/-0.8% and 60.8+/-9.6%, respectively. None of the BALB/c mice in both experimental group and control group died during the experiment. However, all the C57BL/6 mice in the control group died within 23 d and all the vaccinated mice survived well. [[[ Conclusion: ]]] The results imply the potential of recombinant L. lactis as oral delivery vaccination against malaria.