Fig. 1.

Protection from PsV16 infection, one year after immunization with reconstituted spray-dried (SD) VLPs. A) Mice were intramuscularly immunized once with 5 μg of spray-dried MS2-16L2 VLPs (stored at room temperature or 37 °C for 14 months) or control MS2 VLPs without alum hydroxide. One year after immunization, mice were vaginally infected with a high dose of HPV PsV16. Luciferase activity was measured forty-eight hours post challenge and average radiance (p/s/cm²/sr) values for each mouse was determined using Living Image 3.2 software. Each datum represents the average radiance of an individual mouse and each line represents the geometric mean radiance for each group. Statistical analysis was done using one-tailed unpaired t-test. B) IVIS images of bioluminescence signal in the genitals of mice. Average radiance values in A were determined from these images. Control MS2 mice (left image) compared to experimental mice showed high-saturated bioluminescence signal following infection with HPV PsV16.