The molecular signal then triggers a chain reaction that calls E7 to the immune system s attention, prompting an attack on all cells that contain the protein, including the cancer cells. To test whether the vaccine is effective against metastatic cervical cancer, Ji and her fellow researchers developed a line of tumor cells by genetically altering mouse lung cells to include E7, which made the cells similar to cervical cancer cells. A tail vein injection of these cancer cells caused lung tumors in mice in two weeks, and tests showed that the vaccine could prevent this process in a significant portion of the mice, and that it eliminated pre-established lung tumors. The main disadvantage to this vaccine, Ji notes, is that it may not be possible to use it more than one time in the same patient. One exposure may sensitize the immune system to vaccinia, causing it to sweep up the second dose before it begins the chain reaction.
Plans are also under way for an initial human trial of the current vaccine.
Qualifying research studies must involve experimental procedures not husbandry practices that use rodents or rabbits. Applicants should send detailed, double-spaced, previously unpublished manuscripts that explain how pain and distress were reduced in test subjects, the criteria used to assess pain and distress levels, and the reasons for pursuing particular refinement projects. Candidates should also discuss potential impact of their work, and the potential number of animals that could benefit. Formal application forms are not required. For further information, contact Ken Bryer, tel.