Recombinant cytokines and hematopoietic growth factors in allogeneic and autologous bone marrow transplantation

New cancer therapies. Are haematopoietic cell transplants a dead duck?

Recent therapy advances for haematological cancers including new drugs and targeted and immune therapies raise the question whether there is a future for haematopoietic cell transplants. Although encouraging, the survival improvements achieved with these new modalities in persons who might otherwise receive a transplant are modest. Furthermore, these modalities are likely to be complementary, not competitive. For example, randomised trials in multiple myeloma, the most common transplants, indicate an ongoing role for transplant despite new anti-myeloma drugs. Targeted therapies in myeloid cancers are estimated to be effective in only about 10 percent of persons with these cancers. The potential impact of current immune therapies on transplant activity is also limited because: (1) they predominately target B-cell rather than myeloid cancers; (2) many successful immune therapy recipients subsequently receive a transplant; (3) considerable data indicate much of the efficacy of allotransplants results from allogeneic rather than cancer-specific immunity not expected to operate with current immune therapies; and (4) they are at an early development stage with unknown long-term safety and efficacy. These data suggest an ongoing role for haematopoietic cell transplants in diverse haematological and genetic disorders.

Systemic and local delivery of mesenchymal stem cells for heart renovation: Challenges and innovations

In the beginning stage of heart disease, the blockage of blood flow frequently occurs due to the persistent damage and even death of myocardium. Cicatricial tissue developed after the death of myocardium can affect heart function, which ultimately leads to heart failure. In recent years, several studies carried out about the use of stem cells such as embryonic, pluripotent, cardiac and bone marrow-derived stem cells as well as myoblasts to repair injured myocardium. Current studies focus more on finding appropriate measures to enhance cell homing and survival in order to increase paracrine function. Until now, there is no universal delivery route for mesenchymal stem cells (MSCs) for different diseases. In this review, we summarize the advantages and challenges of the systemic and local pathways of MSC delivery. In addition, we also describe some advanced measures of cell delivery to improve the efficiency of transplantation. The combination of cells and therapeutic substances could be the most reliable method, which allows donor cells to deliver sufficient amounts of paracrine factors and provide long-lasting effects. The cardiac support devices or tissue engineering techniques have the potential to facilitate the controlled release of stem cells on local tissue for a sustained period. A novel promising epicardial drug delivery system is highlighted here, which not only provides MSCs with a favorable environment to promote retention but also increases the contact area and a number of cells recruited in the heart muscle.

Factors affecting neutrophil and platelet reconstitution following T cell-depleted bone marrow transplantation: differential effects of growth factor type and role of CD34(+) cell dose

We have performed univariate and multivariate analysis to determine the factors that affect the kinetics of neutrophil and platelet recovery in 546 recipients of T cell-depleted (TCD) marrow allografts. All patients received marrow depleted of mature CD3(+) T cells by complement-mediated lysis using T(10)B(9)-1A3 (n = 489) or Muromonab-Orthoclone OKT3 (n = 57) monoclonal antibodies. Neutrophil engraftment to 0.5 x 10(9)/1 and platelet engraftment to 20 x 10(9)/l were assessed as endpoints. Factors significantly affecting neutrophil or platelet engraftment in the univariate analysis included patient age, T cell dose, anti-thymocyte globulin use, gender, diagnosis at transplant, CMV serostatus, HLA mismatch, CD34 cell dose (n = 249), and growth factor use and type. These variables were included in the multivariate Cox proportional hazards regression model. The results showed that a faster rate of neutrophil engraftment was independently associated with CD34(+) cell dose > or = 5 x 10(6)/kg and most strongly with growth factor administration. Faster platelet engraftment was associated with transplantation for chronic leukemia, CD34(+) cell dose > or = 2 x 10(6)/kg, an HLA matched related donor, and the absence of growth factor use. G-CSF had a higher relative risk (RR) of enhancing neutrophil engraftment than GM-CSF and significantly delayed platelet engraftment. The combined use of G-CSF + GM-CSF was similar to G-CSF alone. The enhancing effect of G-CSF for neutrophil recovery was most striking for patients who engrafted to 0.5 x 10(9)/1 at or before day 12 (RR = 9.5, P < 0.0001) compared to patients who received no growth factor. Conversely, the delaying effect of G-CSF on platelet engraftment was strongest for patients engrafting on or before day 25 (RR = 0.4, P = 0.0004). Of the independent variables affecting engraftment kinetics in recipients of TCD marrow allografts only growth factor, and to a limited extent, CD34(+) cell dose can be controlled by the clinician. A higher CD34(+) cell dose enhances the rate of both neutrophil and platelet engraftment whereas for G-CSF the benefits of myeloid growth factor use in enhancing neutrophil recovery may be partly offset by a delay in platelet engraftment.