Oligoclonal populations of T and B cells in a case of angioimmunoblastic T-cell lymphoma predominantly infiltrated by T cells of the VB5.1 family.

AIMS: Immunohistological and molecular characterisation of a case of peripheral T-cell lymphoma (PTCL) of angioimmunoblastic T-cell lymphoma (AILD) type.

METHODS

Frozen and paraffin wax sections of the diagnostic lymph node were stained with a panel of T- and B-cell lineage monoclonal antibodies. DNA was isolated from the paraffin wax embedded biopsy material for T-cell receptor (TCR) and immunoglobulin (Ig) PCR amplification, and resultant PCR products were cloned and sequenced.

RESULTS

Immunohistological analysis of the presenting lymph node was consistent with an extensive infiltrate of pleomorphic CD3+CD8+ lymphocytes. Most (>80%) of these infiltrating CD3+ cells were also positive for the TCR VB5.1 gene family product, and were shown to be oligoclonal by TCRB PCR amplification and sequencing. Three oligoclones of B cells were also demonstrable by PCR amplification with Ig heavy chain primers and sequencing, a finding at variance with the diagnosis of AILD.

CONCLUSIONS

These data demonstrate the complexity and heterogeneity of PTCL which require extensive histological examination and molecular characterisation.