Young child as a donor of cells for transplantation and lymphocyte based therapies

Living with the threat of losing a child: Parents' experiences of the transplantation process with a severely ill child who received stem cells from a sibling

PURPOSE

When a child needs a hematopoietic stem cell transplant, the seriousness of the child's illness is highlighted. The purpose of this study was to explore parents' experiences of the transplantation process when two children in the family are involved, one severely ill child as the recipient and the other as the donor.

METHODS

In this qualitative study, interviews were conducted with 18 parents of 13 healthy minor donors after successful stem cell transplants. Qualitative content analysis was used to explore parents' experiences.

FINDINGS

The parents described they were living with the threat of losing a child. They lived with an uncertain future as they were confronted with life-changing information. Whether the ill child would survive or not could not be predicted; thus, parents had to endure unpredictability, and to cope with this they chose to focus on positives. Finally, the parents managed family life in the midst of chaos, felt an inadequacy and a perception that the family became a fragmented although close team during hospital stays. They expressed a need for both tangible and emotional support.

CONCLUSIONS

When a child needs a stem cell transplant, the parents feel inadequate to their healthy children including the donating child. It is obvious that they experience an uncertain future and struggle to keep the family together amid the chaos.

PRACTICE IMPLICATIONS

Considering these results, psychosocial support should be mandatory for parents in connection with pediatric HSCT, to enable a process where parents can prepare for the outcome, whether successful or not.

Adverse events related to central venous catheters (CVC) and the influence of CVC characteristics on peripheral blood hematopoietic progenitor cell collection in children

Introduction

The use of peripheral blood progenitor cells (PBPCs) as a source for hematopoietic stem cell transplantation (HSCT) in pediatric healthy donors is still under debate. The risk of a central venous catheter (CVC) placement and catheter-related complications continue to be the main arguments to discourage its use.

Methods

we present a retrospective analysis of 140 PBPC collections in pediatric patients and donors, describing adverse events (AE) related to CVCs as well as the influence of catheterrelated variables on the efficiency of the leukapheresis.

Results

14 CVC-related AEs were recorded (10%). The most common was fever in 5 patients, 4 of which had a catheter-related bacteriemia. Thrombotic events were only observed in 3 patients with active malignancy. A healthy donor presented a moderate bleeding after catheter withdrawal that resolved with local measures, and none of the rest presented any AE. Regarding variables related to the development of AEs, the subject group (patient or donor) was the only one significantly associated (p < 0.0001). Of interest, efficiency was also related to catheter location, being worse in those located in the femoral vein than in into the jugular or the subclavian veins (p < 0.05). In a multivariate analysis, the only variable significantly associated was catheter size (beta 0.238, p < 0.01).

Discussion

Placing a CVC for PBPC collection in pediatric subjects is overall safe; CVC-related complications in pediatric healthy donors are very rare. Furthermore, we should try to place catheters of the largest caliber possible, since the efficiency of the collection is related to this variable.

Peripheral blood stem and progenitor cell collection in pediatric candidates for ex vivo gene therapy: a 10-year series

Hematopoietic stem and progenitor cell (HSPC)-based gene therapy (GT) requires the collection of a large number of cells. While bone marrow (BM) is the most common source of HSPCs in pediatric donors, the collection of autologous peripheral blood stem cells (PBSCs) is an attractive alternative for GT. We present safety and efficacy data of a 10-year cohort of 45 pediatric patients who underwent PBSC collection for backup and/or purification of CD34⁺ cells for ex vivo gene transfer. Median age was 3.7 years and median weight 15.8 kg. After mobilization with lenograstim/plerixafor (n = 41) or lenograstim alone (n = 4) and 1−3 cycles of leukapheresis, median collection was 37 × 10⁶ CD34⁺ cells/kg. The procedures were well tolerated. Patients who collected ≥7 and ≥13 × 10⁶ CD34⁺ cells/kg in the first cycle had pre-apheresis circulating counts of at ≥42 and ≥86 CD34⁺ cells/μL, respectively. Weight-adjusted CD34⁺ cell yield was positively correlated with peripheral CD34⁺ cell counts and influenced by female gender, disease, and drug dosage. All patients received a GT product above the minimum target, ranging from 4 to 30.9 × 10⁶ CD34⁺ cells/kg. Pediatric PBSC collection compares well to BM harvest in terms of CD34⁺ cell yields for the purpose of GT, with a favorable safety profile.

Collection of hematopoietic stem cells and immune effector cells in small children

Apheresis procedures are standard of care for a wide range of indications in children, collection of hematopoietic stem cells being the most frequent one. With increasing numbers of hematopoietic stem cell transplants, advances in graft manipulation techniques and the development of innovative therapies using immune effector cells and gene therapy, apheresis within the pediatric population is growing in demand. While young children have higher circulating white blood cell counts and robustly mobilize hematopoietic stem cells, apheresis machines were designed for use within the adult population and apheresis procedures in children, particularly small children, can be more challenging as vascular access, collection techniques and impact of extracorporeal volumes increase the rate of adverse events. In this article we review topics of particular relevance to hematopoietic stem cell and immune effector cell collections in small children.