Transfusable neutrophil progenitors as cellular therapy for the prevention of invasive fungal infections

The use of mature neutrophil (granulocyte) transfusions for the treatment of neutropenic patients with invasive fungal infections (IFIs) has been the focus of multiple clinical trials. Despite these efforts, the transfusion of mature neutrophils has resulted in limited clinical benefit, likely owing to problems of insufficient numbers and the very short lifespan of these donor cells. In this report, we employed a system of conditionally immortalized murine neutrophil progenitors that are capable of continuous expansion, allowing for the generation of unlimited numbers of homogenous granulocyte-macrophage progenitors (GMPs). These GMPs were assayed in vivo to demonstrate their effect on survival in 2 models of IFI: candidemia and pulmonary aspergillosis. Mature neutrophils derived from GMPs executed all cardinal functions of neutrophils. Transfused GMPs homed to the bone marrow and spleen, where they completed normal differentiation to mature neutrophils. These neutrophils were capable of homing and extravasation in response to inflammatory stimuli using a sterile peritoneal challenge model. Furthermore, conditionally immortalized GMP transfusions significantly improved survival in models of candidemia and pulmonary aspergillosis. These data confirm the therapeutic benefit of prophylactic GMP transfusions in the setting of neutropenia and encourage development of progenitor cellular therapies for the management of fungal disease in high-risk patients.

Cytokine Augmentation Reverses Transplant Recipient Neutrophil Dysfunction against the human fungal pathogen, Candida albicans

BACKGROUND

Solid organ (SOT) and stem cell transplant (SCT) recipients are at increased risk of invasive fungal disease despite normal neutrophil counts. Here, we measure neutrophil anti-Candida activity.

METHODS

Twenty-one SOT and 19 SCT recipients were enrolled 2-4 months post-transplant and compared to 23 healthy control patients (HC). Neutrophils were co-incubated with C. albicans and percent killing, and swarming responses were measured.

RESULTS

Neutrophils from transplant patients had decreased fungicidal capacity compared to HC (42%, 43%, 72%; SCT, SOT, and HC respectively; SCT vs. HC p<0.0001, SOT vs. HC p<0.0001, SOT vs. SCT p=0.8) including diminished ability to control hyphal growth (HC vs SOT and HC vs. SCT, 0.1455 vs. 0.3894, p ≤0.001, 0.1455 vs. 0.6295, p ≤0.0001, respectively). Serum from SCT, but not SOT recipients, inhibited the ability of HC neutrophils to control C. albicans (37%, 45%, 55%; SCT, SOT, and HC, respectively). Neutrophils control of hyphal growth was partially restored with G-CSF or GM-CSF.

CONCLUSION

Despite normal circulating numbers, our data suggests that neutrophils from SOT and SCT recipients mount dysfunctional responses against C. albicans. Intrinsic neutrophil changes and extrinsic serum factors may be responsible for the dysfunction, which is partially reversed with cytokine augmentation.

Development of a protocol to prevent opioid-induced constipation in patients with cancer: a research utilization project

Opioids are the major class of analgesics used in the management of moderate to severe cancer pain, and constipation is a common side effect of opioid administration. While monitoring for quality-assurance, nurses found that 95% of patients interviewed on a 28-bed oncology unit of a Midwestern hospital reported constipation as the major side effect of their opioid regimen for pain control. Through the efforts of a nursing research utilization committee, a protocol to prevent opioid-induced constipation in patients with cancer was developed and implemented.