Stem cell harvesting protocol research in autologous transplantation setting: Large volume vs. conventional cytapheresis

Rapid Cytoreduction by Plateletapheresis in the Treatment of Thrombocythemia

The objective of this chapter is to provide a systematic overview of current knowledge regarding therapeutic apheresis—primarily therapeutic plateletapheresis (TP)—and to summarize evidence-based practical approaches related to cytapheresis treatment of “hyperthrombocytosis” or “extreme thrombocytosis” (ETC). Our results of platelet (Plt) quantitative/qualitative analyses and evaluation of efficacy of apheresis systems/devices—on the basis of Plt removal and in vivo Plt depletion—will be presented. Our preclinical researches confirmed that in Plt concentrates, the initial ratio of discoid shapes was 70%, spherical 20%, and less valuable (dendritic/balloonized) shapes 10%—with morphological score of platelets (MSP = 300–400). After storage, the ratio of discoid and spherical shapes was decreased, while the less valuable ones progressively increased (MSP = 200). Electron microscopy has shown discoid shapes with typical ultrastructural properties. Spherical shapes with reduced electron density and peripheral location of granules/organelles were detected. Also, dendritic shapes with cytoskeletal “rearrangement,” membrane system integrity damages, and pseudopodia formations were documented. Our clinical study demonstrated that TP was useful in ETC treatment and should help prevention of “thrombo-hemorrhagic” events—until chemotherapy, antiplatelet drugs, and other medication take effect. During TP treatment, Plt count and morphology/ultrastructure were examined. Plt functions by multiplate analyzer were evaluated. We concluded that intensive TP was an effective, safe, and rapid cytoreductive treatment for ET.

Prospective identification of potential factors influencing stem cell mobilization and the necessity for plerixafor use in newly diagnosed multiple myeloma patients undergoing autologous stem cell transplantation

Introduction

To study the efficacy and safety of single large volume leukapheresis by using generic G-CSF or G-CSF plus Plerixafor in achieving adequate stem cell yield and various factors influencing thereof in newly diagnosed multiple myeloma patients undergoing autologous stem cell transplant .

Method

This prospective study was undertaken among 55 newly diagnosed multiple myeloma patients undergoing autologous stem cell transplant and aged between 18 and 75 years. Mobilization and harvesting of stem cells were performed by using GCSF or GCSF plus Plerixafor and large volume leukapheresis, respectively. A stem cell yield of ≥2 × 10⁶ kg^–1 and the number of apheresis procedures were primary efficacy endpoints, while the ideal stem cells yield >5 × 10⁶ kg^–1, the engraftment day and D100 response/graft sustainability were secondary endpoints.

Result

The primary endpoint was achieved in all cases in both the groups by using a single LVL leukapheresis procedure. Fulfillment of all the secondary endpoints was satisfactory and comparable in both the groups. Age, pre-apheresis CD34+ count and number of interruptions during the LVL were significant factors influencing the stem cell yield (p < 0.05). Adverse drug reactions during the apheresis and post-ASCT period were manageable.

Conclusion

The LVL is safe and cost-effective in attaining a minimum of CD34+ cells in a single procedure with manageable adverse reactions. Judicious intervention during the procedure may be helpful in ensuring the adequate yield.

Stem cells: Haemobiology and clinical data summarising: A critical review

Stem cells (SC) are the unique and "key-cells" in the human body "working" as a source of producing a large number (proliferation) of mature (differentiation) cells inside different tissues ("cytopoiesis") - while at the same time maintaining the ability to "reproduce" themselves (self-renewal). These events are balanced by interactive signals from the extracellular matrix, as well as microenvironment provided by stromal cells. On the other hand, SC plasticity (so-called "inter-systemic plasticity") is the ability of the most "primitive" (immature) adult SCs to switch to novel identities. The phrase SC plasticity also involves phenotypic potential of these cells, broader than spectrum of phenotypes of differentiated cells in their original tissues. Recent increasing clinical use of cell-mediated therapeutic approaches has resulted in enlarged needs for both, higher quantity of SCs and improved operating procedures during extracorporeal manipulations. The aim of harvesting procedures is to obtain the best SC yield and viability. The goal of optimised cryopreservation is to minimise cellular thermal damages during freeze/thaw process (cryoinjury). Despite the fact that different SC collection, purification and cryopreservation protocols are already in routine use - a lot of problems related to the optimal SC extracorporeal manipulations are still unresolved. The objective of this paper is to provide an integral review of early haemobiological and cryobiological research in the unlimited "SC-field" with emphasis on their entities, recent cell-concepts, extracorporeal manipulative and "graft-engineering" systems. Their therapeutic relevance and efficacy in "conventional" SC transplants or regenerative medicine will be briefly summarised. Finally, in this paper original results will not be pointed out - related to neither SC transplants nor regenerative medicine - but a light will be shed on some of them.

Autologous transplant in the treatment of severe aplastic anemia--a case report

The initial use of immunosuppressive therapy (IST) in severe aplastic anemia (sAA) or reapplication of IST-centered methods following disease relapse is successful only in well-selected patients. The potential treatment by autologous stem cell (SC) transplant in sAA is still an innovative/pioneering therapeutic approach. To our best knowledge, this is the second published case of autologous SC transplant in sAA. The aim of this work was to optimize mobilization and timing for SC harvesting - using our own controlled-rate cryopreservation - with higher CD34(+)/CD90(+) subset yield and recovery in order to obtain complete and long-term hematopoietic reconstitution following autologous SC transplant. We report a 35 year-old sAA male patient who initially underwent IST using rabbit ATG and Cyclosporine A (CsA). He was supportive transfusion dependent for the whole period of IST-phase. After the second IST-cycle, polymorphonuclear (PMN) cell count increase (>2.0 × 10(9)/L) was observed, when SC mobilization, two large volume leukapheresis procedures and following autologous transplant were performed. The yields of harvested CD34(+) and CD34(+)/CD90(+) cells were 5.75 × 10(6)/kgbm and 1.7 × 10(6)/kgbm, respectively. The quantity of applied CD34(+) and CD34(+)/CD90(+) cells in autologous SC transplant were 5.45 × 10(6)/kgbm (7-AAD(CD34)(+)(viability)=95.42%) and 1.63 × 10(6)/kgbm (7-AAD(CD34)(+)(/CD90)(+)(viability)=95.42%), respectively. Hematopoietic reconstitution registered due to second month after autologous SC transplant and he is 24 months in complete medullar, hematological and clinical remission, with normal cytogenetic status - applying only continuous CsA therapy. The results obtained strongly confirm that in sAA, with no allogeneic SC donor, autologous transplant can result in a successful clinical outcome. We suggest that CD34(+)/CD90(+) subset count in peripheral blood and/or cell-harvest could be more valuable predictive factor than total CD34(+) quantity of optimized collection-timing and superior treatment efficacy of autologous SC transplant in sAA.