Related Experiment Videos
Mobilization and selection of peripheral blood hematopoietic progenitors in children with systemic sclerosis
F Locatelli1, C Perotti, L Torretta
1Dipartimento di Scienze Pediatriche, Università di Pavia, IRCCS Policlinico San Matteo, P.le Golgi 2, 27100 Pavia, Italy. f.locatelli@smatteo.pv.it
Insights
This study demonstrates that mobilizing, collecting, and selecting hematopoietic stem cells is safe and feasible in children with autoimmune diseases. These procedures are crucial for autologous transplantation in treating severe autoimmune conditions in pediatric patients.
Area of Science:
- Pediatric Hematology
- Immunology
- Stem Cell Transplantation
Background:
- Autologous stem cell transplantation is a potential treatment for severe autoimmune diseases.
- Data on stem cell collection and selection safety in pediatric autoimmune disease patients were previously lacking.
- This study focuses on three pediatric patients with systemic sclerosis and lung involvement.
Purpose of the Study:
- To evaluate the safety and feasibility of stem cell mobilization, collection, and selection in pediatric patients with autoimmune disease.
- To assess the efficacy of the mobilization and selection process for autologous peripheral blood stem cells.
- To report on the outcomes of hematopoietic stem cell transplantation in this cohort.
Main Methods:
- Patients received chemotherapy and granulocyte colony-stimulating factor (G-CSF) for stem cell mobilization.
- Leukapheresis was performed to collect peripheral blood progenitors.
- CD34+ cells were selected, with T-cell depletion using positive and negative selection methods.
- Patients underwent a preparative regimen followed by transplantation with cryopreserved, lymphocyte-depleted progenitor cells.
Main Results:
- The mobilization and priming regimen was well-tolerated by all pediatric patients.
- Successful stem cell collection was achieved, with adequate CD34+ cell counts.
- The selection process resulted in significant T-cell depletion (at least 2.6-log) while preserving CD34+ cell recovery (21-44%).
- All patients showed prompt hematopoietic engraftment post-transplantation.
Conclusions:
- Mobilization, collection, and selection of hematopoietic progenitors are safe and feasible in children with autoimmune disease.
- These findings support the use of autologous stem cell transplantation in pediatric autoimmune conditions.
- The described methods enable effective stem cell processing for transplantation in this vulnerable population.
Background And Objective:
Autologous transplant of lymphocyte-depleted peripheral blood stem cells has been proposed for treatment of patients with severe autoimmune disease. However, until now, no data are available on the safety and feasibility of both stem cell collection and selection in pediatric patients with these disorders. We report on three children affected by systemic sclerosis with lung involvement, who received chemotherapy and granulocyte colony-stimulating factor (G-CSF) to mobilize autologous peripheral blood progenitors.
Design And Methods:
The priming regimen consisted of cyclophosphamide (CY, 4 g/m(2)) and G-CSF (lenograstim, 10 microg/kg/day starting 2 days after cyclophosphamide administration until stem cell collection). Leukapheresis was performed when WBC and CD34+ cell count were at least 2 x 10(9)/L and 0.03 x 10(9)/L, respectively. In the first patient, positive selection of CD34+ cells was performed through the Ceprate SC stem cell concentrator (CellPro, Bothell, WA, USA). In the remaining 2 children, progenitor cells were also purged with negative selection of CD4+ and CD8+ lymphocytes performed by means of the Isolex 300i device (Baxter).
Results:
All patients tolerated the priming regimen well and did not present any sign of autoimmune disease exacerbation. Collection was successful in all children and the number of CD34+ cells before selection ranged between 10.7 x 10(6) and 17.6 x 10(6)/kg of patient body weight. The selection of haematopoietic stem cells in the 3 patients resulted in at least 2. 6-log T-cell depletion of the cell content, with a recovery of the initial value of CD34+ cells comprised between 21 and 44%. After, a preparative regimen consisting of CY (200 mg/kg over 4 days) and Campath-1 G in vivo (10 mg/day for 2 consecutive days), patients were transplanted using cryopreserved lymphocyte-depleted progenitor cells. In all cases, a prompt hematopoietic engraftment was observed.
Interpretation And Conclusions:
Taken together these data suggest that mobilization, collection and selection of hematopoietic progenitors are safe and feasible in children with autoimmune disease.