All IHC stains will include a positive control tissue

• CD1a can be used in conjunction with S-100 to differentiate between the various malignant and benign histiocytic proliferations:

* This pattern of staining is seen in both benign (e.g. dermatopathic lymphadenopathy) and malignant (histiocytic) LC proliferations. However, LC's in histiocytosis X have been found to be CD4 positive, while benign LC's are CD4 negative.

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

• CD1a is a 49kDa cell surface glycoprotein found on human Langerhans cells and thymocytes, but not on peripheral T-cells

Staining pattern

• Cell membrane and/or diffuse cytoplasmic

References

1. Ornvold et al, Virchows Archiv-A, 416(5):403-10, 1990.
2. Shamoto et al, Advances in Exp. Med & Biology, 378:139-41, 1995.