High-throughput sequencing and analyses of the TCR repertoire

We co-cultured T cells with Mo-DCs exposed to ConA for 24 h and used multiplex PCR and next-generation sequencing to detect the TCRa repertoire.The length of the amino acids of CDR3 in each group was 4–59 amino acids, and all presented a normal distribution. Moreover, the length of the amino acids of CDR3 was not different between ConA and control groups. The number of clonotypes and unique clonotypes in the ConA group was increased significantly compared with that in control groups. However, the difference of high-frequency CDR3 amino-acid clonotypes between ConA and control groups was not significant (cutoff = 0.2%). Our results for the V and J gene segments of TCR diversity showed a marked increase in the number of clonotypes in the ConA group. The Shannon–Wiener Diversity Index of ConA was lower than that in the control group, and the top-20 V and J gene segments of ConA showed a higher usage frequency than that in the control group, but the difference between ConA and the control group was not significant. Collectively, these data indicated that ConA could reduce CDR3 diversity and augment usage of high-frequency CDR3. Overall design: 3 samples of ConA, 3 samples of Cim, 3 samples of Cy, 3 samples of DNCB,3 samples of SDS and 3 samples of Control