# CD57

Source: https://onco.cc/targets/cd57/  
OnCo record `cd57` (Target). Data CC BY-NC 4.0, attribute "Data from OnCo (onco.cc)"; commercial use needs a licence.

## TL;DR

CD57 appears on immune cells that have divided many times and are near the end of their working life. It is the usual way of telling a worn-out T cell from a fresh one.

## Summary

CD57 is the carbohydrate epitope made by the glucuronyltransferase B3GAT1, and it accumulates on lymphocytes that have gone through many rounds of division. It marks terminal differentiation and replicative senescence rather than exhaustion proper, and the distinction matters: a senescent cell has run out of divisions, whereas an exhausted cell is being actively restrained by checkpoints and may be released by blocking them. CD57 is usually read alongside the loss of CD28, and on natural killer cells it marks the most mature, most cytotoxic population.

## Fields

- Kind: Target
- Last checked: 2026-10-16
- Also known as: B3GAT1; HNK-1
- Tags: immune-marker
- Symbol: B3GAT1
- Class: surface-antigen
- Biology: Glucuronyltransferase making the HNK-1 carbohydrate epitope; accumulates on repeatedly divided lymphocytes.
- Where found: Terminally differentiated T cells; Mature natural killer cells

## Sources

- Wikipedia: https://en.wikipedia.org/wiki/CD57
- HGNC:921: https://www.genenames.org/data/gene-symbol-report/#!/hgnc_id/HGNC:921

## Connected records

- targets: [CD28](https://onco.cc/targets/cd28/), [CD8](https://onco.cc/targets/cd8/)
- terms: [NK cell](https://onco.cc/terms/nk-cell/), [T-cell exhaustion and CAR-T persistence](https://onco.cc/terms/t-cell-exhaustion-term/)

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JSON: https://onco.cc/api/v1/entities/cd57.json