Exploration of Immunology

Table 2. Single-cell technologies in TIL research.

Technology	Strengths	Limitations	Application in TIL therapy
scRNA-seq	High-resolution transcriptome profiling identifies functional states	No direct protein expression; expensive; complex data analysis	Stratifying patients, identifying exhaustion targets
scTCR-seq	Tracks clinical diversity and neoantigen specificity	Requires integration with scRNA-seq for full functional insights	Selection of tumor-reactive clones for adoptive therapy
CyTOF	Multiplex protein profiling identifies phenotypic subsets	Lower throughput than scRNA-seq; limited to known protein markers	Optimizing TIL enrichment protocols
Spatial transcriptomics	Maps the spatial localization of gene expression in situ	Limited resolution; currently lower gene coverage than scRNA-seq	Targeting TIL-enriched tumor niches

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scRNA-seq: single-cell RNA sequencing; scTCR-seq: single-cell T-cell receptor sequencing; CyTOF: mass cytometry; TIL: tumor-infiltrating lymphocyte.

Declarations

Acknowledgments

We thank Saveetha University and our respective guides and co-guides for their continued support and feedback during the preparation of this manuscript.

Author contributions

CK: Conceptualization, Methodology, Investigation, Formal analysis, Data curation, Visualization, Writing—original draft. RV: Methodology, Writing—review & editing. AS: Writing—review & editing. VVP: Conceptualization, Supervision, Project administration, Writing—review & editing. All authors read and approved the final manuscript.

Conflicts of interest

The authors declare that they have no competing interests.

Ethical approval

Not applicable.

Consent to participate

Not applicable.

Consent to publication

Not applicable.

Availability of data and materials

All the data discussed is publicly available from cited repositories, such as GEO and TCGA.

Funding

This research received no specific grant from any funding agency, commercial entity, or not-for-profit organization. The authors declare that they did not receive any financial support for the preparation of this article.

Copyright

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Open Exploration maintains a neutral stance on jurisdictional claims in published institutional affiliations and maps. All opinions expressed in this article are the personal views of the author(s) and do not represent the stance of the editorial team or the publisher.

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