- Old Rhesus Macaques Treated with Interleukin-7 Show Increased TREC Levels And Respond Well to Influenza Vaccination. Aspinall, R., Pido-Lopez, J., Imami, N., Henson, S.M., Ngom, P.T., Morre, M., Niphuis, H., Remarque, E., Rosenwirth, B., Heeney, J.L. Rejuvenation research (2007)