# HHLA2 (B7-H7)

Source: https://onco.cc/targets/hhla2/  
OnCo record `hhla2` (Target). Data CC BY-NC 4.0, attribute "Data from OnCo (onco.cc)"; commercial use needs a licence.

## TL;DR

HHLA2 is a B7 relative found on gut, kidney and lung tissue and on many tumours; it can both encourage and restrain T cells depending on the receptor. No drug against it is in the corpus yet.

## Summary

HHLA2 (chromosome 3q13.13) costimulates T cells through TMIGD2 in the context of TCR-mediated activation, enhancing proliferation and cytokine production through an AKT-dependent cascade; it is expressed at high levels in colon, kidney, testis, lung and pancreas, at lower levels in small intestine, liver and skeletal muscle, and among immune cells in B cells, dendritic cells and macrophages but not T cells (UniProt Q9UM44). B7-H3, B7x and HHLA2 form the third group of the B7-CD28 family, with antagonistic antibodies and agonistic fusion proteins emerging (Janakiram et al. 2017, Immunol Rev).

## Fields

- Kind: Target
- Last checked: 2026-09-24
- Also known as: B7-H7; B7H7; B7-H5; B7y; HHLA2 member of B7 family
- Tags: checkpoint-map
- Symbol: HHLA2
- Class: checkpoint
- Biology: A group III B7 family member; its costimulatory receptor is TMIGD2 (CD28H).
- Where found: Colon, kidney, testis, lung, pancreas; B cells, dendritic cells, macrophages (UniProt Q9UM44)

## Notes

- Prevalence not recorded: HGNC and UniProt carry no positivity rates.

## Sources

- HGNC HGNC:4905: https://www.genenames.org/data/gene-symbol-report/#!/hgnc_id/HGNC:4905
- UniProt Q9UM44: https://www.uniprot.org/uniprotkb/Q9UM44/entry
- NCBI Gene 11148: https://www.ncbi.nlm.nih.gov/gene/11148
- Janakiram et al. 2017, Immunol Rev (Europe PMC): https://europepmc.org/article/MED/28258693

## Connected records

- targets: [B7-H3](https://onco.cc/targets/b7h3/), [B7-H4 (VTCN1)](https://onco.cc/targets/b7h4/), [CD28](https://onco.cc/targets/cd28/)
- pathways: [The cancer-immunity cycle](https://onco.cc/pathways/cancer-immunity-cycle/)
- terms: [Checkpoint (two meanings)](https://onco.cc/terms/checkpoint/)

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JSON: https://onco.cc/api/v1/entities/hhla2.json