Cd34+ progenitor cells likely are involved in the good functional recovery after intracerebral hemorrhage in humans.

Bone marrow-derived stem/progenitor cells (CD34(+) progenitor cells) were demonstrated to play an important role in the regeneration of damaged brain tissue. Our aim was to study the influence of CD34(+) progenitor cells in the outcome of intracerebral hemorrhage (ICH). Thirty-two patients with primary ICH (64.0% male, mean age 67.1 ± 10.8 years) were prospectively included in the study within 12 hr of symptom onset. The main outcome variable was good functional outcome at 3 months (modified Rankin scale ≤ 2). Circulating CD34(+) progenitor cell levels were measured by flow cytometry at admission and at 7 ± 1 days, and serum levels of growth factors (determined by ELISA) were measured at admission and at 24 and 72 hr. Circulating levels of CD34(+) progenitor cells at day 7 were independently associated with good functional outcome at 3 months (OR 1.17, CI95% 1.06-1.39, P = 0.012). On the other hand, CD34(+) progenitor cells at day 7 were negatively correlated with residual cavity volume at 3 months (r = -0.607, P = 0.001). Serum levels of vascular endothelial growth factor (r = 0.386), angiopoietin 1 (r = 0.518), brain-derived neurotrophic factor (r = 0.484), and stromal cell-derived factor-1α (r = 0.837) but not granulocyte-colony stimulating factor (r = -0.038) at 72 hr showed a strong correlation with CD34(+) progenitor cell levels at day 7. These findings suggest that CD34(+) progenitor cells may participate in the functional recovery of ICH patients.