TNFRSF9 and systemic lupus erythematosus: In the study by Foell et al., three i.p. injections of agonistic anti-CD137 antibody given to NZB x NZW F1 lupus-prone mice between the ages of 26 and 35 weeks reversed acute SLE, abrogated chronic disease and lengthened the survival of the mice from the mean of 10 months to more than 2 years [34].