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Alias/Synonym: Helper/Inducer T-cells, Thymocyte and Monocyte Subsets

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:
The CD4 molecule (T4) is a single chain transmembrane glycoprotein that is associated with HLA class II antigen recognition. It defines the helper subset of T-lymphocytes, and is present on monocytic cells. It is the receptor for HIV to enter the cells. Most cases of T-cell lymphoma/leukemia, with some exceptions, express CD4. It is also present in histiocytic sarcoma, LCH, blastic plasmacydoid dendritic cell neoplasm, some cases of AML and some inflammatory conditions.
Turnaround Time:
1 day(s)
Reference Ranges: