All IHC stains will include a positive control tissue

• CD23 is useful in a panel of immunostains (on frozen and/or paraffin sections) to differentiate between the various types of low grade B-cell lymphoma (CD23 is always positive in CLL/WDLL and only rarely and weakly positive in marginal zone lymphomas, follicular center cell lymphomas)
• CD23 was shown to stain Reed-Sternberg/Hodgkin’s cells in over 80% of cases in some series (nodular sclerosis type, LP, LD types). Approximately 15% of nodular sclerosing cases can be negative. In few cases CD23 was more useful than CD30, generally showing weaker staining. Therefore it should be used as part of a panel
• CD23 has been reported to be positive in rare cases of high grade T-cell lymphoma

Submit a formalin-fixed, paraffin-embedded tissue

Formalin-fixed, paraffin-embedded (FFPE) tissue block

FFPE tissue section mounted on a charged, unstained slide

Ambient (preferred)

• Unlabeled/mislabeled block
• Insufficient tissue
• Slides broken beyond repair

Immunohistochemical staining and microscopic examination

If requested, an interpretive report will be provided

Specifications

• CD23 is a 45 kD membrane glycoprotein identified as the low affinity IgE receptor (FcERII)
• CD23 reacts with activated B lymphocytes and some neoplastic B lymphocytes, dendritic reticulum cells, epidermal Langerhans cells, macrophages, some T lymphocytes, NK cells, Reed-Sternberg/Hodgkin’s cells, mast cells, occasionally endothelial cells

 Staining pattern

• Cell membrane and diffuse cytoplasmic
• Intracellular (‘Golgi pattern’) in Reed-Sternberg/Hodgkin’s cells

References

1. Rowlands et al. Journal of Pathology, 160:239-243, 1990.
2. Murray et al. Journal of Pathology, 16J:125-128, 1991