# CD22 expression (CD22-positive)

Source: https://onco.cc/biomarkers/cd22-expression/  
OnCo record `cd22-expression` (Biomarker). Data CC BY-NC 4.0, attribute "Data from OnCo (onco.cc)"; commercial use needs a licence.

## TL;DR

CD22 is a second B-cell antigen, kept even when CD19 is lost. Inotuzumab ozogamicin is labelled for CD22-positive acute lymphoblastic leukaemia.

## Summary

CD22 is measured by flow cytometry on blasts; more than 90 percent of B-ALL is CD22-positive. Inotuzumab ozogamicin (Besponsa) is a CD22-directed antibody-drug conjugate labelled for relapsed or refractory CD22-positive B-cell precursor ALL in adults and children aged one and over. CD22-directed CAR-T cells are in trials for CD19-negative relapse after blinatumomab or CD19 CAR-T.

## Fields

- Kind: Biomarker
- Last checked: 2026-09-23
- Also known as: CD22-positive; CD22+; CD22 expression; CD22 positive ALL
- Tags: biomarker; surface-antigen

## Sources

- Besponsa prescribing information (DailyMed): https://dailymed.nlm.nih.gov/dailymed/drugInfo.cfm?setid=cc7014b1-c775-411d-b374-8113248b4077

## Connected records

- biomarkers: [CD19 expression (CD19-positive)](https://onco.cc/biomarkers/cd19-expression/), [CD20 expression (CD20-positive)](https://onco.cc/biomarkers/cd20-expression/)
- cancers: [Acute lymphoblastic leukaemia](https://onco.cc/cancers/all-leukemia/), [Relapsed and refractory acute lymphoblastic leukaemia in children](https://onco.cc/cancers/all-paediatric-relapsed/)
- drugs: [Inotuzumab ozogamicin](https://onco.cc/drugs/inotuzumab-ozogamicin/)
- terms: [Antigen escape (antigen loss, lineage switch)](https://onco.cc/terms/antigen-escape/), [Flow cytometry (immunophenotyping)](https://onco.cc/terms/flow-cytometry/)
- targets: [CD22](https://onco.cc/targets/cd22/)

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JSON: https://onco.cc/api/v1/entities/cd22-expression.json