T-cell receptor beta constant 1 (TRBC1) (TRBC1)

T-cell receptor beta constant 1 (TRBC1) is one of two mutually exclusive constant regions of the T-cell receptor (TCR) beta chain, the other being TRBC2 [11]. In healthy individuals, the T-cell population is a polyclonal mixture of approximately 40% TRBC1-positive and 60% TRBC2-positive cells [15]. Because T-cell malignancies are clonal expansions, the malignant cells uniformly express either TRBC1 or TRBC2, but not both [3, 11]. This biological exclusivity allows for a unique therapeutic strategy where targeting TRBC1 can eliminate the malignant clone while preserving the TRBC2-positive healthy T-cell compartment [1, 3]. This approach maintains a degree of cellular immunity and avoids the profound, life-threatening immunosuppression associated with pan-T-cell depletion [11]. Current therapeutic developments include CAR-T cell therapies such as AUTO4 and novel antibody-drug conjugates (ADCs) that utilize TRBC1 as a lineage-specific, clonotype-stable marker for treating peripheral T-cell lymphomas and leukemias [1, 7, 12].

Other names

TCR beta constant 1T-cell receptor beta-1 chain C regionTRBC1T-cell receptor constant beta chain-1

Selective depletion of TRBC1-positive T cells (both malignant and healthy) while sparing the TRBC2-positive healthy T-cell compartment to maintain host immune competence [1, 3, 11].