Stages of T-cell receptor protein expression in T-cell acute lymphoblastic
leukemia
D Campana, JJ van Dongen, A Mehta, E Coustan-Smith, IL Wolvers-Tettero, K Ganeshaguru and G Janossy
Department of Immunology and Haematology, Royal Free Hospital, School of
Medicine, London, UK.
In this study five monoclonal antibodies (MoAbs) to T-cell receptor (TCR)
proteins (WT31, alpha F1, beta F1, TCR delta-1 and delta TCS-1) were used
to identify discrete maturative stages in 40 cases of T-cell acute
lymphoblastic leukemia (T-ALL). These MoAbs reacted exclusively with CD3+ T
cells and did not label B-lineage and myeloid cells. In 17 of the 40 T-ALL
cases studied the leukemic blasts lacked membrane and cytoplasmic TCR
chains (group I). In 12 cases cells did not have membrane CD3/TCR but
expressed cytoplasmic TCR proteins heterogenously: nine cases had
cytoplasmic TCR beta chains (beta F1+, alpha F1-; group II), one case had
cytoplasmic TCR alpha chains (alpha F1+, beta F1-; group III), and two
cases were labeled by both alpha F1 and beta F1 MoAbs (group IV). The
remaining 11 cases were mCD3+: nine were TCR alpha beta+ (group Va) and two
exhibited TCR gamma delta (TCR delta-1+, delta TCS-1+; group Vb). The
analysis of the TCR beta, -gamma, and - delta gene configurations in 23 of
the 40 T-ALLs showed that: (1) the lack of TCR protein expression was due
to the lack of TCR gene rearrangements only in one of nine cases; (2) five
of five TCR beta+, TCR alpha- cases studied had germline TCR alpha genes
(ie, no detectable TCR delta gene deletions); (3) seven of eight cases with
TCR delta gene deletions expressed TCR alpha proteins, whereas in 12 of 20
of the T-ALLs with TCR beta gene rearrangements the synthesis of the
corresponding protein occurred; only 2 of 16 cases with rearranged TCR
delta genes expressed TCR delta chains. The T-ALL categories identified
with anti-TCR MoAbs did not have additional characteristic phenotypic
patterns and may correspond to the normal stages of T-cell development more
precisely than those defined by other differentiation antigens.
Volume 77,
Issue 7,
pp. 1546-1554,
04/01/1991
Copyright © 1991 by The American Society of Hematology
