- Human pathology

Home > A. Molecular pathology > CD34


MIM.142230 1q32

Wednesday 25 May 2005

Definition: CD34 is a monomeric cell surface sialomucin with a molecular mass of approximately 110 kD that is selectively expressed on human hematopoietic progenitor cells.


At least three endothelial cell ligands can bind L-selectin:
- glycan-bearing cell adhesion molecule-1 (GlyCAM-1), a secreted proteoglycan found on HEVs of lymph node
- mucosal addressin cell adhesion molecule-1 (MadCAM-1), expressed on endothelial cells in gut-associated lymphoid tissues
- CD34, a proteoglycan on endothelial cells (and bone marrow cells).

The protein backbones of all these ligands are modified by specific carbohydrates, which are the molecules actually recognized by the selectins (SELs).

Expression in normal cells

- human hematopoietic progenitor cells
- endothelial cells
- adipocytes

Expression in tumors : CD34+ tumors

- lipomas
- solitary fibrous tumors
- dermatofibrosarcoma protuberans and giant cell fibroblastoma
- +/- acute leukemias
- nodular hairy dendritic hamartoma of the newborn
- smooth muscle hamartoma

Diagnostic use in IHC

- Differential diagnosis neurofibroma vs desmoplatic melanoma

Open references


Paywall References

- CD61, CD31, and CD34 improve diagnostic accuracy in gastric antral vascular ectasia and portal hypertensive gastropathy: An immunohistochemical and digital morphometric study. Westerhoff M, Tretiakova M, Hovan L, Miller J, Noffsinger A, Hart J. Am J Surg Pathol. 2010 Apr;34(4):494-501. PMID: 20351488