Allogeneic hematopoietic stem cell transplantation

The impact of NKG2A and NKG2D receptors and HLA-E and MICA ligands polymorphisms on post-transplant complications after paediatric allogeneic HSCT: a single-centre experience

Introduction: Natural Killer cells are the first subpopulation of lymphocytes that reconstitute after allogeneic haematopoietic stem cell transplantation (HSCT). Their activity is regulated by various receptor-ligand interactions, including stimulation of the activating NKG2D receptor by the MICA molecule, and inhibitory NKG2A receptor interacting with the HLA-E. In this study the research effort focused on the effect of selected NKG2A and NKG2D receptors and their ligands (HLA-E and MICA molecules) polymorphisms that may affect the pathomechanisms of post-transplant complications after HSCT in children. Methods: One hundred donor-recipient pairs from a single paediatric transplantation centre were investigated. Altogether six single nucleotide substitutions (NKG2A rs7301582; NKG2D rs1049174, rs1154831; HLA-E rs1264457; MICA rs1051792, rs1063635) were genotyped, and the influence of polymorphisms was analysed on acute and chronic graft-versus-host disease (GvHD), cytomegalovirus (CMV) infection incidence, disease relapse and survival. Results: The distribution of the evaluated polymorphisms did not differ between patients and their donors. The results showed a significant influence of HLA-E rs1264457 polymorphism in patients' HLA-E*01:01 allele, which was associated with increased risk of CMV infection (p = 0.050), especially in children positive for CMV IgG before transplantation (p = 0.001). Furthermore, the effect of HLA-E*01:01 allele on CMV infections was more evident in children above the age of 7 years (p = 0.031). Strong tendencies (0.05 < p < 0.10) towards association with the risk of acute GvHD were also observed for the NKG2A or MICA polymorphisms of the recipients. In addition, NKG2D rs1154831 AA and MICA rs1063635 GG might play a protective role as they were not present in any recipient who died after transplantation. Conclusion: In summary, there is emerging evidence that genotyping results of NKG2 receptors and their ligands, may have prognostic value for the outcome of paediatric allogeneic HSCT, but more extensive studies performed on larger groups of donors and transplant recipients are required to confirm these observations.

The immediate impact of physical function and quality of life after hematopoietic stem cell transplantation

PURPOSE

Although hematopoietic stem cell transplantation (HSCT) is a curative treatment for hematologic malignancies, HSCT survivors often experience declined physical function and quality of life (QoL). However, the physical function and QoL changes in acute post-transplant patients remain unclear. This study aimed to investigate the impact of HSCT on physical function.

METHOD

This retrospective control study included 107 HSCT patients. Physical function was evaluated weekly from admission to discharge using the de Morton Mobility Index (DEMMI). Impaired physical function was defined as a baseline raw ordinal DEMMI score of < 17 and a decrease of ≥ 2 points. We collected the Visual Analog Scale (VAS), European Organization for Research and Treatment of Cancer Quality of Life Questionnaire (EORTC QLQ-C30), and Zung Self-rating Depression Scale (SDS) at enrollment and discharge.

RESULTS

Based on the DEMMI scores, 41 patients (38.3%) showed impaired physical function. A notable decrease in the DEMMI score was found in the first week after HSCT. In the EORTC QLQ-C30, physical function differed between the groups at admission and discharge. The good physical function group showed better cognitive function and social function. For the SDS, the impaired physical function group showed significantly higher depression at discharge.

CONCLUSION

A third of the patients showed physical impairment during the acute transplant period. Patients with low physical function suffered more from depression and lower QoL. Evaluating patients' pre-transplant physical function and early detection is needed as impaired physical function mainly occurs at 1 week post-transplant.

Update on clinical trials: genetic targets in breast cancer

Breast cancer is the most commonly diagnosed cancer in women in United States. From data of American Cancer Society from 2007 reported total of 178,480 women diagnosed with breast cancer. The death rate from breast cancer has decreased in North America over time, but still accounts for second highest cancer death, following lung cancer. Breast cancer is staged based on tumor size, nodal involvement, and distant metastasis like any other solid tumors. However clinical staging is not the only important factor in management of breast cancer. Various molecular features divides breast cancer into many subgroups - that act differently, and respond differently from therapy. Thus the focus of breast cancer treatment has evolved focusing on specific targets. The most important biologic markers in subtyping of breast cancer so far are hormone receptor positivity and HER2/neu protein expression. Five molecular subtypes using intrinsic gene set include Basal mRNA, HER2 + mRNA, Luminal AmRNA, Luminal B mRNA, and Normal-like mRNA. In addition, better understanding of genetic target of breast cancer has given us arsenal of personalized, and more effective treatment approach.This review will focus on examples that highlight several mechanism of tumorigenesis, giving us not just understanding of gene pathways and the molecular biology, that could lead us to therapeutic target. Several important molecular targets have been investigated in preclinical and clinical trials, others are yet to be explored. We will also describe genetic mechanisms discovery related to overcoming resistance to current targeted therapies in breast cancer, including hormone receptor expression and HER 2- neu amplification. We will also review other exciting developments in understanding of breast cancer, the tumor microenvironment and cancer stem cells, and targeting agents in that area.

Enhanced angiogenesis by multiple release of platelet-rich plasma contents and basic fibroblast growth factor from gelatin hydrogels

The objective of this study is to evaluate the angiogenic effects induced by biodegradable gelatin hydrogel granules incorporating mixed platelet-rich plasma (PRP) growth factor mixture (PGFM) and bioactive basic fibroblast growth factor (bFGF). The PRP was prepared by a double-spinning technique for isolating animal bloods, followed by treatment with different concentrations of calcium chloride (CaCl(2)) solution. The CaCl(2) solution treatment activated the platelets of PRP, allowing the release of various growth factors, such as platelet-derived growth factor (PDGF)-BB, vascular endothelial growth factor (VEGF), transforming growth factor (TGF)-β(1), and epithelial growth factor (EGF). In the PRP treated with different CaCl(2) solutions, high amounts of representative platelet growth factor, PDGF-BB, VEGF, EGF, and TGF-β(1) were detected in the CaCl(2) concentrations of 1, 2, and 4 wt.% compared with higher or lower ones. The PRP treated was impregnated into gelatin hydrogel granules freeze-dried at 37°C for 1h, and then the percentage of PGFM desorbed from the gelatin hydrogel granules was evaluated. The percentages of PDGF-BB, VEGF, EGF, and TGF-β(1) desorbed tended to decrease with decreasing CaCl(2) concentration. Taken together, the CaCl(2) concentration to activate PRP for PGFM release was fixed at 2 wt.%. In vitro release tests demonstrated that the PGFM was released from the gelatin hydrogel granules with time. For the gelatin hydrogels incorporating PGFM and bFGF, the time profile of PDGF-BB or bFGF release was in good correspondence with that of gelatin hydrogel degradation. The gelatin hydrogel granules incorporating mixed PGFM and bFGF were prepared and intramuscularly injected to a mouse leg ischemia model to evaluate the angiogenic effects in terms of histological and laser Doppler perfusion imaging examinations. As controls, hydrogel granules incorporating bFGF, PGFM, and platelet-poor plasma were used for the angiogenic evaluation. The number of blood vessels newly formed and the percentage of anti-α-smooth muscle actin antibody-positive cells increased around ischemic sites injected with the gelatin hydrogel granules incorporating mixed PGFM and bFGF, in marked contrast to other control groups. The blood reperfusion level of ischemic tissues was enhanced by the hydrogel granules incorporating mixed PGFM and bFGF, whereas no enhancement was observed for other groups. It is concluded that the dual-release system of PGFM and bFGF from gelatin hydrogel granules shows promise as a method to enhance angiogenic effects.

CD133+ cell content does not influence recovery time after hematopoietic stem cell transplantation

BACKGROUND

Infusion of an adequate dose of CD34+ mononuclear hematopoietic stem cells (HSCs) is the single most important variable to assure success in hematopoietic grafting. CD133+ HSCs constitute the CD34+ subgroup with higher differentiation potential. The number of granulocyte-colony-stimulating factor (G-CSF)-mobilized CD133+ HSCs administered during hematopoietic grafting and its relationship with the number of days needed to regain hematopoiesis was determined.

STUDY DESIGN AND METHODS

Thirty-eight patients with malignant hematologic diseases who received an autologous (n = 15) or allogeneic (n = 23) HSC transplant were prospectively evaluated. G-CSF was administered for 5 days at 10 microg/kg/day. Hematopoietic progenitors were recovered from peripheral blood on day 5 by leukopheresis. CD34+ and CD133+/CD34+ cell populations were quantified by flow cytometry; the number of days to hematologic recovery was documented.

RESULTS

A median dose of 4.56 x 10(6)/kg CD34+ HSCs (range, 1.35 x 10(6)-14.6 x 10(6)) was recovered and transplanted; of these grafted cells, a median 3.25 x 10(6) were also CD133+ (range, 1.25 x 10(6)-14.3 x 10(6)). In the autologous group, the median number of days to reach a platelet (PLT) count of 20 x 10(9)/L or greater was 12, and 15 days to obtain a neutrophil count of 0.5 x 10(9)/L or greater; in the allogeneic group 13 and 16 days, respectively, were required (p > 0.05). A median 76.5% of G-CSF-mobilized CD34+ HSCs coexpressed the CD133+ antigen (range, 23.1-97.9).

CONCLUSIONS

A higher number of CD133+/CD34+ HSCs in the graft was not clearly associated with a shorter neutrophil or PLT recovery time in either allogeneic or autologous recipients.

Platelet characteristic antigens of CD34+ cells in cryopreserved cord blood: a study of platelet-derived microparticles in transplant processing

BACKGROUND AND OBJECTIVES

In previous studies, we found that platelet microparticles (PMPs) bind to cord blood (CB) CD34+ cells and transfer adhesion molecules to them, which enhances their engraftment. Before applying this phenomenon in actual transplants, we investigated the effect of PMPs on cryopreserved CD34+ cells in CB.

MATERIALS AND METHODS

We cryopreserved 18 CB units, then evaluated the binding of PMPs to CD34+ cells after thawing, by varying the expression of platelet characteristic antigens (CD41a, CD61, CD62P and CXCR4) on these cells. Adherence of the CD34+ cells, coated with freeze/thaw-induced PMPs, to endothelium and fibronectin was also studied, as were the effects of thrombin-induced PMPs from both fresh and preserved CB platelets.

RESULTS

PMPs induced by freezing and thawing adhered less well to CD34+ cells than did those from fresh CB, and cells coated with these PMPs had poor adherence. However, thrombin-induced PMPs from both fresh and preserved CB platelets bound equally well to cryopreserved CD34+ cells and improved their adhesion properties.

CONCLUSIONS

PMPs could be a useful tool for enhancing engraftment after CB transplantation.