Progenitor cells and CD34+ cells are often referred to interchangeably as stem cells. While this oversimplification is technically correct, there are many distinctions between the origins, functions, and uses of progenitor cells and CD34+ cells.

What is the Difference Between Progenitor and CD34+ Cells?

Despite their many similarities, the most significant difference between the two cell types is that progenitor cells have a limited number of divisions, while CD34+ cells can divide and replicate indefinitely.


CD34+ stem cells give rise to all hematopoietic cells in the body, but progenitor cells are more targeted in their differentiation and can only produce a limited set of cells within a particular lineage (erythroid, myeloid, lymphoid). There are several stages of development for a progenitor cell to transform into a fully mature, differentiated cell.


CD34+ cells first originate as embryonic stem cells in the inner cell mass of blastocysts. These stem cells differentiate and give rise to every other cell type found in the human body.

Progenitor cells are descendants of CD34+ cells and are a stepping stone between the parent stem cell and the fully differentiated target cell.

Activation & Collection

Hematopoietic stem cells reside in bone marrow, peripheral blood circulation, and other tissues in adults, as well as cord blood in infants. They generally remain in the bone marrow until they are needed to repair or replenish.

In the case of donor collection, stem cells are collected from peripheral blood or bone marrow in adults. Donors typically receive injections of G-CSF to mobilize the stem cells into the bloodstream for collection.

Alternatively, stem cells can be harvested directly from bone marrow. And in the case of newborns, stem cells are collected from cord blood.



Progenitor vs. CD34+ Cells

Progenitor Cells

Origin: Stem Cells
Function: Repair Cell Damage
Division: Limited
Potency: Unipotent or Oligopotent
Self-Renewability: No

CD34+ Cells

Origin: Inner Cell Mass or Blastocysts
Function: Repair Cell Damage
Division: Unlimited
Potency: Pluripotent or Totipotent
Self-Renewability: Yes

Clinical Applications
Restoration of Bone Marrow Function, Replacement of Leukemic Marrow with Healthy Marrow

Research Applications
Understanding Development of Individual Cell Lineages

1 Comment

  1. Thank You, Anne, Specially for a comparison table, I was reading above and was not able to understand much but the table prescribed things properly and was able to clear my all queries.

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