CD34
CD34 is an antigen selectively expressed on human lymphoid and myeloid hematopoietic progenitor/early
precursor cells. The antigen is also expressed on vascular endothelium. We have found that the antibody
that is most reliable in paraffin sections is QBEND10, a monoclonal antibody made in mice against human
endothelial cells. We use the antibody with a microwen-based heat induced epitope retrieval technique.
CD34 works well both in formalin fixed and in B5 fixed material and does not appear to be materially
inhibited by decalcification.
We have had a particular interest in studying CD34 in human bone marrows. The antigen is found expressed in
1-2% of the total nucleated cells in normal human bone marrows. Reactive marrow conditions and the
administration of hematopoietic cytokines which are known to increase the number of CD34+ peripheral blood
cells, do not measurably increase this percentage. About two-thirds of all cases of ALL and about one-third
of AML are CD34+. We and others have demonstrated that there is a good correlation between the percentages
of CD34 positivity in marrow by flow cytometry and immunohistochemistry. As a result, we have found the
CD34 immunostain to be a value in assessing minimal residual disease in patients with acute leukemias that
are CD34+, and have demonstrated that there is good correlation between the presence of minimal residual
disease as documented by cytogenetics and by CD34 immunostaining. In addition we have shown that CD34
immunostain may be used to subclassify the different phases of CML. CD34 immunostain may also be useful in
discriminating between aplastic anemia and hypoplastic myelodysplastic syndrome.
References
- Orazi A, Cattoretti G, Schiro' R, et al: rhIL-3 and rhGM-CSF administered in vivo after high dose
cyclophosphamide cancer chemotherapy: Effect on the hematopoiesis and microenvironment in the human bone
marrow. Blood 1992;79:2610.
- Orazi A, Neiman RS, Cualing H, et al: CD34 immunostaining of bone marrow biopsies is a reliable way to
classify the phases of chronic myeloid leukemia. Am J Clin Pathol 1994;101:426.
- Orazi A, Gordon MS, Neiman RS, et al: In vivo effects of recombinant human stem cell factor treatment:
a morphologic and immunohistochemical study of bone marrow biopsies. Am J Clin Pathol 1995;103:177.
- Orazi A. CD34 immunoperoxidase staining for the diagnosis of myelodysplastic syndromes and chronic
myeloid leukemia (Letter) J Clin Pathol 1995;48:884.
- Orazi A, Albitar M, Heerema NA, et al: Hypoplastic myelodysplastic syndromes can be distinguished from
acquired aplastic anemia by CD34 and PCNA immunostaining of bone marrow biopsy specimens. Am J Clin Pathol
1997;107:268. (Editorial: Am J Clin Pathol, 1997;107:261.)
- Soligo D, Delia D, Oriani A, et al: Identification of CD34+ cells in normal and pathological bone
marrow biopsies by QBEnd10 monoclonal antibody. Leukemia 1991;5:1026.
- Soligo DA, Oriani A, Annaloro C, et al: CD34 Immunohistochemistry of bone marrow biopsies: Prognostic
significance in primary myelodysplastic syndromes. Am J Hematol 1994;46:9.
- Rimsza LM, Viswanatha DS, Winter SS, Leith CP, Frost JD, Foucar K. The presence of CD34+ cell clusters
impending relapse in children with acute lymphoblastic leukemia receiving maintenance chemotherapy. Am J
Clin Pathol 1998;110:313.
- Tong J, Gordon MS, Srour EF, et al: The effect of in vivo administration of recombinant methionyl human
stem cell factor on the number of human marrow hematopoietic stem cells. Trans Assoc Amer Phys
1993;106:134.
- Worapongpaiboon S, Budke H, Orazi A, et al: Immunohistologic assessment of CD34 expression in pediatric
bone marrow sections, a potentially useful technique to assess minimal residual disease (MRD) in acute
leukemias. United States and Canadian Academy of Pathology Meeting, Washington, D.C., March 23-29, 1996.
Lab Inv 1996;74:152A.
|
