Box plots of the unique sequence numbers of each sub-region and diversity evaluation.

Unique number represents the number of unique sequences within the reads. a The unique number of sub-regions including FR1, CDR1, FR2, CDR2, FR3, CDR3, and FR4 in three samples. b Diversity evaluation using the normalized unique number by length, which equals to unique number divided by average length of each sub-region. Box plot explanation: upper horizontal line of box, 75th percentile; lower horizontal line of box, 25th percentile; horizontal bar within box, the median of the three samples’ data; upper end of the whisker, maximum of the three samples’ data; lower end of the whisker, minimum of the three samples’ data.