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Alias/Synonym: Dendritic Cells, C3d Receptor, B-cells

CPT Code: 88342

Specimen Type, Preferred:
Formalin fixed paraffin embedded tissue
Specimen Type, Alternate:
Sample Quantity, Preferred:
1 block
2 slides
Sample Quantity, Minimum:
Transport Container:
Paraffin block
Unstained slides
Transport Temperature:
Room temperature
Collection Instructions:
Block and slide identifiers should be clearly written and match exactly with the specimen ID and specimen labeling as noted on the requisition.
Slides should be positively charged and cut at 3-4 microns for each stain/antibody ordered.
Specimen Stability:
Rejection Criteria:
No liquid specimens.
Uncharged slides
Clinical Significance:
CD21 antigen is a type I integral membrane glycoprotein of molecular weight 140 kD, which functions as the receptor for the C3d fragment of the third complement component. The CD21 molecule, present on mature B cells, is involved in transmitting growth-promoting signals to the interior of the B cell and acts as a receptor for Epstein-Barr virus. CD21 antigen is reported to be found in B cell chronic lymphocytic leukemias and in a subset of T cell acute lymphocytic leukemias but is absent on T lymphocytes, monocytes and granulocytes. CD21 antigen is also reported to be expressed in follicular dendritic cells and in follicular and mantle cell lymphomas, mature leukemias and lymphomas.
Turnaround Time:
1 day(s)
Reference Ranges: