Response: Natalizumab-induced mobilization of CD34⁺ hematopoietic progenitor cells

We thank Vuaillat et al for reading our paper¹  carefully with great interest.

Within this short correspondence we hope to elucidate the questions raised:

1. All 5 untreated patients met both the McDonald and the Barkhoff criteria and were diagnosed between 2002 and 2006 with the relapsing-remitting form of the disease. Therefore they had experienced more than one relapse episode of the disease.

2. The patients had the following blood-circulating CD34⁺ counts: 0.57/μL; 0.8/μL; 1.06/μL; 1.44/μL and 1.68/μL.

3. For CD34⁺ subset analysis we performed dual-color phenotyping, and all circulating CD34⁺ cells belonged to the subset of more committed progenitors coexpressing CD38.