Chagas' disease: TCRBV9 over-representation and sequence oligoclonality in the fine specificity of T lymphocytes in target tissues of damage

The TCRBV9 segment was systematically over-represented in the target tissues for each T. cruzi strain: sciatic nerve and spinal cord in RA and skeletal muscle in CA-I-infected mice. The analysis of CDR3 sequence polymorphism in the same tissues showed a high proportion of identical TCRBV9 clones in RA-infected mice: 66.6% of the TCRBV9 clones found in sciatic nerve and spinal cord expressed one out of four major CDR3 rearrangements. Sequence identity was shared among clones from sciatic nerve and spinal cord, tissues that are also damaged by passive transfer of CD8 + TL. Those observations are consistent with an antigen driven T-cell expansion sequestered at the inflammation site and demonstrate - for the first time - the presence of an oligoclonal repertoire in the antigen recognition site of over-represented T cells in nervous system tissues in chronic Chagas' disease.