Study of the T-cell receptor repertoire by CDR3 spectratyping.

The T-cell receptor (TCR) is the key player within the so called immunological synapse and the analysis of its repertoire offers a picture of both versatility and wideness of the whole immune T-cell compartment. Among the different approaches applied to its study the so-called spectratyping identifies the pattern of the third complementarity determining region (CDR3) length distribution in each one of the beta variable (TRBV) subfamilies encoded by the corresponding genes. This technique consists in a CDR3 fragment analysis through capillary electrophoresis, performed after cell separation, RNA extraction and reverse transcriptase PCR. This review will run through the most relevant studies which have tried to dissect the TCR repertoire usage in patients with different immune-mediated and infective diseases as well as solid or haematologic malignancies.