Long-term safety of granulocyte colony-stimulating factor in normal donors: is it all clear?

Pre-Treatment of Transplant Donors with Hydrogen Sulfide to Protect against Warm and Cold Ischemia-Reperfusion Injury in Kidney and Other Transplantable Solid Organs

Ischemia-reperfusion injury (IRI), a pathological condition resulting from prolonged cessation and subsequent restoration of blood flow to a tissue, is an inevitable consequence of solid organ transplantation. Current organ preservation strategies, such as static cold storage (SCS), are aimed at reducing IRI. However, prolonged SCS exacerbates IRI. Recent research has examined pre-treatment approaches to more effectively attenuate IRI. Hydrogen sulfide (H₂S), the third established member of a family of gaseous signaling molecules, has been shown to target the pathophysiology of IRI and thus appears to be a viable candidate that can overcome the transplant surgeon's enemy. This review discusses pre-treatment of renal grafts and other transplantable organs with H₂S to mitigate transplantation-induced IRI in animal models of transplantation. In addition, ethical principles of pre-treatment and potential applications of H₂S pre-treatment in the prevention of other IRI-associated conditions are discussed.

Cancer incidence in healthy Swedish peripheral blood stem cell donors

Granulocyte colony-stimulating factor (G-CSF) has been used for over 20 years to obtain peripheral blood stem cells from healthy donors for allogeneic stem cell transplantation. Concerns have been raised about a potentially increased cancer incidence in donors after donation, especially regarding haematological malignancies. In a prospective Swedish national cohort study, we studied the cancer incidence after donation in 1082 Swedish peripheral blood stem cell donors, donating between 1998 and 2014. The primary objective was to evaluate if the cancer incidence increased for donors treated with G-CSF. With a median follow-up time of 9.8 years, the incidence of haematological malignancies was 0.85 cases per 1000 person-years, and did not significantly differ from the incidence in age-, sex- and residence-matched population controls (hazard ratio 1.70, 95% confidence interval (CI) 0.79-3.64, p value 0.17), bone marrow donors or non-donating siblings. The total cancer incidence for peripheral blood stem cell donors was 6.0 cases per 1000 person-years, equal to the incidence in matched population controls (hazard ratio 1.03, 95% CI 0.78-1.36, p value 0.85), bone marrow donors or non-donating siblings. In this study of healthy peripheral blood stem cell donors, the cancer incidence was not increased after treatment with G-CSF.

Allogeneic Peripheral Blood Stem Cell Transplant: Correlation of Donor Factors with Yield, Engraftment, Chimerism, and Outcome: Retrospective Review of a Single Institute During a 3-Year Period

BACKGROUND

Donor factors have a variable correlation with cluster of differentiation (CD)34+ cell dose in allogeneic peripheral blood stem cell (PBSC) harvests. CD34+ cell dose affects the speed of hematopoietic recovery and percentage of donor chimerism in the recipient.

METHODS

A total of 25 allogeneic PBSC transplants performed during a 3-year period were included. All donors underwent mobilization with filgrastim. Leukapheresis, flowcytometric CD34+ cell enumeration, and chimerism analysis were performed and correlated with recipient outcome.

RESULTS

Besides age, all other donor parameters had a positive correlation with CD34+ cell count. Engraftment kinetics and chimerism had a positive correlation with the CD34+ yield of the PBSC product. Acute graft-vs-host disease (GVHD) was observed in patients with complete chimerism at day 30 after transplantation.

CONCLUSION

Adequate CD34+ cell yield happens in healthy donors, independent of donor demographic patterns with G-CSF only. A diverse population of donors can thus be approached for Matched Unrelated Donor (MUD) transplants. An accurate quantitative analysis of early donor chimerism in the recipient (at day 30) is an excellent tool for post-transplant monitoring for acute GvHD.

Absence of damaging effects of stem cell donation in unrelated donors assessed by FISH and gene variance screening

ASTRACT

Granulocyte-Colony-Stimulating factor (G-CSF) is currently the standard mobilising agent for peripheral blood stem cell (PBSC) donation. Concerns that it may trigger chromosome aberrations similar to those observed in leukaemia patients were refuted but long-term effects of G-CSF mobilisation on genome integrity remains unclear. In the setting of a multi-centre clinical trial we screened blood samples from 50 PBSC donors at cellular and gene level for aberrations common in haematological malignancies using fluorescence in situ hybridisation (FISH) and next generation sequencing (NGS) assays. Analysis of samples collected before, on the day of donation, 90 and 180 days after G-CSF admission confirmed the absence of short-term effects in PBSC donors on both quiescent and dividing cells. This data did not differ from the results of 50 individuals tested 3-5 years after bone marrow donation and 50 healthy persons. NGS using a panel targeting 54 genes recurrently affected in myeloid disorders (TruSight Myeloid panel, Illumina) showed that the gene profiles of samples from 48 PBSC donors remained stable throughout the study period. These data strongly indicate absence of detrimental effects on the genome integrity caused by PBSC donation.

How Could We Slow or Reverse the Human Aging Process and Extend the Healthy Life Span with Heterochronous Autologous Hematopoietic Stem Cell Transplantation

The senescence of the immune system contributes considerably to the age-related diseases that are the main causes of death after the age of 65. In this study, we present an appealing option for the prevention of immune senescence and slowing or reversing the aging process, which can be achieved by heterochronous autologous hematopoietic stem cell transplantation (haHSCT), where healthy autologous bone marrow stem cells are collected from donors while young, cryopreserved and stored for a long period, and reinfused at a later time when indicated. After reinfusion and homing, these young HSCs could participate in normal hemato- and immunopoiesis and improve several immune functions by expanding the immune- as well as hematopoietic cell repertoire. Several animal studies have already confirmed the feasibility of this procedure, which extended the longevity of the treated animals. If translated to human medicine, haHSCT could prevent or mitigate age-related immune defects and extend the healthy life span. In this review, we describe the concept of haHSCT, recent studies that confirm its feasibility, and discuss the further research needed to translate this heterochronous methodology.

Protecting the Health and Safety of Cell and Tissue Donors

Centers involved with collecting the starting material for cell and tissue therapies are obligated to protect the recipient's and donor's health and safety. All donors face risks during and after the collection which can be minimized by prescreening donors and excluding those that the collection would place at increased risk of physical harm. Another important part of protecting donors is the use of appropriate collection facilities. Donor risk can also be reduced by using specially designed collection devices and ancillary equipment, using only trained collection staff and limiting the volume or quantity of biologic material collected. Donors should be monitored during and after the collection for adverse events, and should adverse events occur, they should be promptly and appropriately treated. Protecting the safety of cell, gene and tissue donors is particularly difficult because of the wide variety in the types of donors and material collected. Biological material used to manufacture cell and tissue therapies is collected from healthy volunteers, matched-related, matched-unrelated and autologous donors. Precautions should be taken to ensure that the team of medical professionals evaluating related donors is not the same as the team caring for the transplant recipient in order to be sure that the donor evaluation is not biased and the donor is not coerced into donating. In conclusion, protecting cell and tissue donors requires the use of the practices developed to protect blood donors and the implementation of many other measures.

Angiogenic factors in chronic lymphocytic leukaemia (CLL): Where do we stand?

The role of angiogenesis in haematological malignancies such as chronic lymphocytic leukaemia (CLL) is difficult to envision, because leukaemia cells are not dependent on a network of blood vessels to support basic physiological requirements. Regardless, CLL cells secrete high levels of major angiogenic factors, such as vascular endothelial growth factor (VEGF), basic fibroblast growth factor (bFGF), and platelet derived growth factor (PDGF). Nonetheless, it remains unclear how most angiogenic factors regulate accumulation and delayed apoptosis of CLL cells. Angiogenic factors such as leptin, granulocyte colony-stimulating factor (G-CSF), follistatin, angiopoietin-1 (Ang1), angiogenin (ANG), midkine (MK), pleiotrophin (PTN), progranulin (PGRN), proliferin (PLF), placental growth factor (PIGF), and endothelial locus-1 (Del-1), represent novel therapeutic targets of future CLL research but have remained widely overlooked. This review aims to outline our current understanding of angiogenic growth factors and their relationship with CLL, a still uncured haematopoietic malignancy.

Granulocyte colony-stimulating factor off-target effect on nerve outgrowth promotes prostate cancer development

The hematopoietic growth factor granulocyte colony-stimulating factor (G-CSF) has a role in proliferation, differentiation and migration of the myeloid lineage and in mobilizing hematopoietic stem and progenitor cells into the bloodstream. However, G-CSF has been newly characterized as a neurotrophic factor in the brain. We recently uncovered that autonomic nerve development in the tumor microenvironment participates actively in prostate tumorigenesis and metastasis. Here, we found that G-CSF constrains cancer to grow and progress by, respectively, supporting the survival of sympathetic nerve fibers in 6-hydroxydopamine-sympathectomized mice and also, promoting the aberrant outgrowth of parasympathetic nerves in transgenic or xenogeneic prostate tumor models. This provides insight into how neurotrophic growth factors may control tumor neurogenesis and may lead to new antineurogenic therapies for prostate cancer.

Granulocyte-colony stimulating factor decreases the extent of ovarian damage caused by cisplatin in an experimental rat model

Objective

To investigate whether granulocyte-colony stimulating factor (G-CSF) can decrease the extent of ovarian follicle loss caused by cisplatin treatment.

Methods

Twenty-one adult female Sprague-Dawley rats were used. Fourteen rats were administered 2 mg/kg/day cisplatin by intraperitoneal injection twice per week for five weeks (total of 20 mg/kg). Half of the rats (n=7) were treated with 1 mL/kg/day physiological saline, and the other half (n=7) were treated with 100 µg/kg/day G-CSF. The remaining rats (n=7, control group) received no therapy. The animals were then euthanized, and both ovaries were obtained from all animals, fixed in 10% formalin, and stored at 4℃ for paraffin sectioning. Blood samples were collected by cardiac puncture and stored at -30℃ for hormone assays.

Results

All follicle counts (primordial, primary, secondary, and tertiary) and serum anti-Müllerian hormone levels were significantly increased in the cisplatin+G-CSF group compared to the cisplatin+physiological saline group.

Conclusion

G-CSF was beneficial in decreasing the severity of follicle loss in an experimental rat model of cisplatin chemotherapy.

G-CSF enhances resolution of Staphylococcus aureus wound infection in an age-dependent manner

This study tested the hypothesis that heightened bacterial colonization and delayed wound closure in aged mice could be attenuated by granulocyte colony-stimulating factor (G-CSF) treatment. Previously, we reported that aged mice had elevated bacterial levels, protracted wound closure, and reduced wound neutrophil accumulation after Staphylococcus aureus wound infection relative to young mice. In aseptic wound models, G-CSF treatment improved wound closure in aged mice to rates observed in young mice. Given these data, our objective was to determine if G-CSF could restore age-associated differences in wound bacterial burden and closure by increasing wound neutrophil recruitment. Young (3- to 4-month) and aged (18- to 20-month) BALB/c mice received three dorsal subcutaneous injections of G-CSF (250 ng/50 μL per injection) or saline control (50 μL per injection) 30 min after wound infection. Mice were killed at days 3 and 7 after wound infection, and bacterial colonization, wound size, wound leukocyte accumulation, and peripheral blood were evaluated. At days 3 and 7 after wound infection, bacterial colonization was significantly reduced in G-CSF-treated aged mice to levels observed in saline-treated young animals. Wound size was reduced in G-CSF-treated aged animals, with no effect on wound size in G-CSF-treated young mice. Local G-CSF treatment significantly enhanced neutrophil wound accumulation in aged mice, whereas there was no G-CSF-induced change in young mice. These data demonstrate that G-CSF enhances bacterial clearance and wound closure in an age-dependent manner. Moreover, G-CSF may be of therapeutic potential in the setting of postoperative wound infection or chronic nonhealing wounds in elderly patients.