Donor serostatus and CMV infection and disease among recipients of prophylactic granulocyte transfusions

Granulocyte Transfusion Therapy

Bacterial and fungal infections continue to be a major cause of morbidity and mortality in severely neutropenic patients undergoing aggressive chemotherapy regimens or hematopoietic stem cell transplantation. Traditional granulocyte transfusion therapy, a logical approach in treating these infections, has been available for many years, and several controlled studies have shown this therapy to be useful. However, granulocyte transfusion therapy fell out of favor because the results were not clinically impressive, and adverse results were reported. These disappointing results were felt to be, in part, because of the low doses of granulocytes provided. More recent studies have attempted to increase the numbers of transfused cells by stimulating normal granulocyte donors with G-CSF (+/-corticosteroids). With these techniques, the number of granulocytes transfused can be increased 3-4 fold. The cells have been shown to circulate in recipients, and daily transfusions are capable of maintaining normal or near-normal blood neutrophil counts in previously severely neutropenic patients. The cells appear to function normally by a variety of in vitro and in vivo tests. Clinical benefit, as defined by survival or clearance of infection, has not been definitively determined. Results of an ongoing randomized controlled clinical trial should be available in the near future.

Cytomegalovirus viral load and virus-specific immune reconstitution after peripheral blood stem cell versus bone marrow transplantation

Peripheral blood stem cell (PBSC) products contain more T cells and monocytes when compared with bone marrow (BM), leading to fewer bacterial and fungal infections. Cytomegelovirus (CMV) viral load and disease as well as CMV-specific immune reconstitution were compared in patients enrolled in a randomized trial comparing PSBC and BM transplantation. There was a higher rate of CMV infection and disease during the first 100 days after transplantation among PBSC recipients (any antigenemia/DNAemia: PBSC, 63% vs BM, 42%, P = .04; CMV disease: PBSC, 17% vs BM, 4%, P = .03). By 2 years, CMV disease rates were similar. The early increase in CMV events correlated temporarily with lower CMV-specific CD4(+) T helper and CD8(+) cytotoxic T lymphocyte function at 30 days after transplantation in PBSC recipients. By 3 months after transplantation and thereafter, CMV-specific immune responses were similar between BM and PBSC recipients. In conclusion, higher CMV infection and disease rates occurred in PBSC transplant recipients early after transplantation. These differences may be because of a transient delay in CMV-specific immune reconstitution following PBSC transplantation.

Granulocyte transfusions in the G-CSF era. Where do we stand?

The efficacy of granulocytes transfusions (GTX) in either the prevention or treatment of neutropenic sepsis has been a controversial issue. Early studies employing steroid mobilised GTX showed variable, dose-dependent results and significant pulmonary toxicity was reported. With the introduction of the recombinant myeloid growth factor, granulocyte-colony stimulating factor (G-CSF), the quantity of granulocytes that could be harvested was substantially increased leading to renewed interest in the clinical application of GTX. The administration of G-CSF to normal donors leads to significantly higher pre-harvest neutrophil counts and consequently larger granulocyte harvests. Infusion of G-CSF stimulated GTX results in measurable increases in the recipients' neutrophil count and may reduce the duration and severity of neutropenia. However, the efficacy of these GTX in treating or preventing established neutropenic sepsis remains to be established in prospective controlled clinical trials.

Granulocyte?colony-stimulating factor?mobilized prophylactic granulocyte transfusions given after allogeneic peripheral blood progenitor cell transplantation result in a modest reduction of febrile days and intravenous antibiotic usage

BACKGROUND

It was hypothesized that transfusion of two granulocyte-colony-stimulating factor (G-CSF)-mobilized prophylactic granulocyte components into allogeneic peripheral blood progenitor cell (PBPC) transplant patients during the regimen-related neutropenic interval would result in clinical benefit.

STUDY DESIGN AND METHODS

HLA-matched sibling PBPC donors (n=151) were biologically randomized based on ABO mismatch to donate granulocyte components (Cohort G) or not donate granulocytes (control group, Cohort C). ABO-matched donors who did not meet other study-specific criteria were reassigned to Cohort C.

RESULTS

Feasibility, defined as the proportion of ABO-matched donors who underwent granulocyte collections, was 42 percent (53 of 125). The percentage of patients who developed fever during the initial hospitalization was greater in Cohort C versus Cohort G (82.7% vs. 64.2%; p=0.03). In the interval from when granulocyte transfusions were initially given in Cohort G (Day +3 or Day +5) until neutrophil engraftment, the number of febrile days was less in Cohort G versus Cohort C (median, 0 vs. 1; Mann-Whitney p=0.003). The median number of days of intravenous antibiotics given during the initial hospitalization was less in Cohort G versus Cohort C (9 vs. 11; Mann-Whitney p=0.03), a difference accounted for in the interval from Day +3 or Day +5 to neutrophil recovery. There was no significant difference in length of the initial hospital stay, acute graft-versus-host disease rates, or 100-day survival between the two cohorts.

CONCLUSION

This prospective study demonstrates a modest, but significant, benefit of G-CSF-mobilized HLA-matched prophylactic granulocyte transfusions in neutropenic allogeneic PBPC recipients.

The role of granulocyte transfusions in neutropenic patients

The precise role for donor granulocyte infusions remains to be delineated, partly because of the lack of defined clinical trials. The aim of this article is to summarize the studies undertaken so far and highlight the logistical problems associated with undertaking future studies. We also aim to provide a practical guide to the application of this therapeutic approach.