CD79a
From haematologyetc.co.uk
DETAILS
CD38 helps mobilise intracellular calcium to activate a wide array of cell functions. In haematological cell types CD38 it is widely expressed by lymphoid cells )B, T and NK) as well as myeloid precursor cells and mature myeloid cells. It has particular diagnostic importance for lymphocytes where CD38 expression is acquired as stem cells commit to B-cell lineage, then is lost as mature B cells emerge from bone marrow before being re-acquired at the time of plasma cell differentiation.
What is its diagnostic role?
The wide expression of CD38 limits its diagnostic value except in very specific circumstances:
- The co-expression of CD38 with CD138 can identify normal or neoplastic plasma cells
- Expression of CD38 in chronic lymphocytic leukaemia (>20% of cells) may associated with poorer outcome
Other relevant information: CD38 is a therapeutic target, daratumumab is a monoclonal antibody which binds to CD38 and is used in the treatment of myeloma.
SUMMARY TABLES
| Expression of CD38 by primitive lymphoid cells: ALL and haematogones | |||||||
|---|---|---|---|---|---|---|---|
| pro-B ALL | early pre-B ALL | pre-B ALL | B-ALL | pro-T ALL | mature-T ALL | AML | Haematogones |
| * | stg | ||||||
* low expression correlates with subtype e.g. APML
| Expression of CD38 by mature B cells: B-lymphoproliferative disorders | |||||||
|---|---|---|---|---|---|---|---|
| CLL | MCL | FL | HCL | HCv | MZL | LPL | PCL |
| * | ** | stg/mod | |||||
*May indicate adverse prognostic when present on more than 20% of cells
**May be weak