Aluminum adjuvant fibrin ETs are not required to maintain an antigen depot. C57BL/6 mice, and FibA Het (+/−), or FibA KO (−/−) recipient mice were vaccinated with 3K-OVA plus alum. Spleen and lymph node cells from 508 mice and OT-I mice, containing TCR Tg T cells specific for I-A^b-3K, and K^b-SIINFEKL, respectively, were isolated from TCR Tg mice, pooled, labeled with CFSE, and adoptively transferred into recipients. Two days later, mice were killed and splenic TCR Tg T cells were analyzed by fluorescence-activated cell sorting for proliferation of Tg CD4 T cells (A) and Tg CD8 T cells (B). The genotype of the recipient mouse is indicated in each histogram. The gray histogram indicates staining of T cells transferred to control mice that were vaccinated 12 days previously with soluble 3K-OVA. Similar results were obtained from the inguinal lymph node (not shown). There were 3 mice per group and the mouse with median CFSE dilution is shown from each group. Transfers were done on 3 days, 2 of which are shown (day 12 and day 19).