Graft-versus-leukemia effect of nonmyeloablative stem cell transplantation

The role of embryonic stem cells, transcription and growth factors in mammals: A review

Mammals represent a relevant species in worldwide cultures with significant commercial value. These animals are considered an attractive large animal model for biomedical and biotechnology research. The development of large animal experimental models may open alternative strategies for investigating stem cells (SCs) physiology and potential application in the veterinary field. The embryonic stem cells (ESCs) are known to possess natural pluripotency that confers the ability to differentiate into various tissues in vivo and in vitro. These notable characteristics can be useful for research and innovative applications, including biomedicine, agriculture and industry. Transcription factors play a crucial role in preserving stem cell self-renewal, whereas growth factors are involved in both growth and differentiation. However, to date, many questions concerning pluripotency, cellular differentiation regulator genes, and other molecules such as growth factors and their interactions in many mammalian species remain unresolved. The purpose of this review is to provide an overall review regarding the study of ESCs in mammals and briefly discuss the role of transcription and growth factors.

Equine Mesenchymal Stem Cells: Properties, Sources, Characterization, and Potential Therapeutic Applications

Properties like sustained multiplication and self-renewal, and homing and multilineage differentiation to undertake repair of the damaged tissues make stem cells the lifeline for any living system. Therefore, stem cell therapy is regarded to carry immense therapeutic potential. Though the dearth of understanding about the basic biological properties and pathways involved in therapeutic benefits currently limit the application of stem cells in humans as well as animals, there are innumerable reports that suggest clinical benefits of stem cell therapy in equine. Among various stem cell sources, currently adult mesenchymal stem cells (MSCs) are preferred for therapeutic application in horse owing to their easy availability, capacity to modulate inflammation, and promote healing. Also the cells carry very limited teratogenic risk compared to the pluripotent stem cells. Mesenchymal stem cells were earlier considered mainly for musculoskeletal tissues, but now may also be utilized in other diverse clinical problems in horse, and the results may be extrapolated even for human medicine. The current review highlights biological properties, sources, mechanisms, and potential therapeutic applications of stem cells in equine practice.

Advances in the Use of Stem Cells in Veterinary Medicine: From Basic Research to Clinical Practice

Today, several veterinary diseases may be treated with the administration of stem cells. This is possible because these cells present a high therapeutic potential and may be injected as autologous or allogenic, freshly isolated, or previously cultured. The literature supports that the process is safe and brings considerable benefits to animal health. Knowledge about how adult stem cells modulate the molecular signals to activate cell homing has also been increasingly determined, evidencing the mechanisms which enable cells to repair and regenerate injured tissues. Preclinical studies were designed for many animal models and they have contributed to the translation to the human clinic. This review shows the most commonly used stem cell types, with emphasis on mesenchymal stem cells and their mechanistic potential to repair, as well as the experimental protocols, studied diseases, and species with the highest amount of studies and applications. The relationship between stem cell protocols utilized on clinics, molecular mechanisms, and the physiological responses may offer subsidies to new studies and therefore improve the therapeutic outcome for both humans and animals.

Adoptive therapy with donor lymphocyte infusion after allogenic hematopoietic SCT in pediatric patients

The aim of this study was to analyse the experience of Polish Pediatric Group for Hematopoietic Stem Cell Transplantation in respect to donor lymphocyte infusion procedure. The study included 51 pediatric patients with malignant (45) and non-malignant (6) diseases treated with DLI in the period 1993-2012. The indications for DLI were as follows: (1) increasing recipient chimerism after non-ablative hematopoietic SCT (18 patients); (2) immunomodulation after a reduced intensity conditioning regimen (2 patients); (3) increase in minimal residual disease detection (3 patients); and (4) relapse (28 patients). DLI was carried out at a median of 6 (0.5-79) months after SCT. DLI was administered as either a single-dose (in 19 cases) or in escalating-dose regimens (in 32 cases). The median total dose of CD3-positive T cells was 28.0 (0.1-730.0) × 10(6)/kg body weight. The time for assessment of DLI efficacy ranged from 0 to 70 (median 3) months. At evaluation, 18 patients experienced CR, 3 achieved PR, 19 showed relapse and 11 rejected the graft. DLI was found to be effective in 39% of cases. Complications of the procedure occurred in 18 patients; of these, 2 died. To sum up DLI shows efficacy in a significant percentage of children. Mortality related to the therapy adverse effects is low. However, this method requires standardization.

Feasibility of non-TBI conditioning with busulfan and fludarabine for allogeneic stem cell transplantation in lymphoid malignancy

BACKGROUND/AIMS

This retrospective study evaluated the transplantation outcomes of patients with adult lymphoid malignancies who received chemotherapy-based conditioning with busulfan and fludarabine (BuFlu) and busulfan and cyclophosphamide (BuCy2).

METHODS

Thirty-eight patients (34 with acute lymphoblastic leukemia and 4 with lymphoblastic lymphoma) were included in the current study. The conditioning regimen was BuCy2 for 14 patients and BuFlu for the remaining 24 patients. Eight and 13 patients were high risk disease in the BuCy2 and BuFlu groups, respectively.

RESULTS

The cumulative incidence of grade II-IV acute graft-versus-host disease (GVHD) was 56.5% and 55.2% and that of extensive chronic GVHD 17.0% and 55.6% (p = 0.018) for the BuFlu and BuCy2 groups, respectively. The 3-year relapse rate was 27.8% and 31.4% and 3-year overall survival 34.3% and 46.8% for the BuFlu and BuCy2 groups, respectively. Treatment-related mortality (TRM) was significantly lower in the BuFlu group (16.9%) than in the BuCy2 group (57.1%, p = 0.010). In multivariate analyses, the BuFlu regimen was identified as an independent favorable risk factor for TRM (hazard ratio [HR], 0.036; p = 0.017) and extensive chronic GVHD (HR, 0.168; p = 0.034).

CONCLUSIONS

Our BuFlu regimen would appear to be an acceptable conditioning option for lymphoid malignancies, including high-risk diseases. It was safely administered with a lower TRM rate than BuCy2 conditioning.