Donor T cells with identical TCRβ CDR3 nucleotide sequences can be identified in both autoimmune and indirect alloimmune repertoires. (A) Lethally irradiated Balb/c mice were transplanted with B6 BM and B6 spleen cells, and pooled spleen cells were then transferred by IV injection into B6 Rag animals. In a separate experiment, pooled spleen cells from acute GVHD mice were transferred into chimeric B6 Rag BM → Balb/c Rag mice. Vβ2 amino acid sequences derived from the colons of mice from both experiments are depicted. The amino acid sequence that was found in both cohorts of mice is shown in bold. (B) Lethally irradiated Balb/c mice (n = 10) were transplanted with B6 BM and B6 spleen cells. Pooled spleen cells from euthanized GVHD animals 26 days after transplantation were transferred by IV injection into either nonirradiated B6 Rag animals or B6 Rag BM → Balb/c Rag chimeric mice. Pathology scores for colon damage in B6 Rag and chimeric B6 Rag BM → Balb Rag mice (n = 5/group) are shown. NS indicates not significant. (C) Vβ8.1 amino acid sequences derived from the colons of mice. Amino acid sequences found in both cohorts of mice that received the same splenic T-cell inoculum are shown in bold.