The appropriate sequencing depth for single-cell V(D)J sequencing depends on several factors, including sample complexity, sequencing depth, and experimental design.

Generally, the goal of single-cell V(D)J sequencing is to obtain comprehensive clonotype information, requiring sufficient sequencing depth to support high-quality rearrangement and clonotype identification. As a rule of thumb, each single cell should ideally have at least 4,000 reads to ensure high-quality V(D)J analysis results.

It's important to consider the specific experimental design and research question when choosing the appropriate sequencing depth. Some studies may require deeper sequencing, while others may need less. Therefore, the sequencing depth should be chosen based on the actual needs of the study.