ProPACC: Protocol for a Trial of Integrated Specialty Palliative Care for Critically Ill Older Adults.

BACKGROUND: Each year, approximately one million older adults die in American intensive care units (ICUs) or survive with significant functional impairment. Inadequate symptom management, surrogates' psychological distress and inappropriate healthcare use are major concerns. Pioneering work by Dr. J. Randall Curtis paved the way for integrating palliative care (PC) specialists to address these needs, but convincing proof of efficacy has not yet been demonstrated. DESIGN: We will conduct a multicenter patient-randomized efficacy trial of integrated specialty PC (SPC) vs. usual care for 500 high-risk ICU patients over age 60 and their surrogate decision-makers from five hospitals in Pennsylvania. INTERVENTION: The intervention will follow recommended best practices for inpatient PC consultation. Patients will receive care from a multidisciplinary SPC team within 24 hours of enrollment that continues until hospital discharge or death. SPC clinicians will meet with patients, families, and the ICU team every weekday. SPC and ICU clinicians will jointly participate in proactive family meetings according to a predefined schedule. Patients in the control arm will receive routine ICU care. OUTCOMES: Our primary outcome is patient-centeredness of care, measured using the modified Patient Perceived Patient-Centeredness of Care scale. Secondary outcomes include surrogates' psychological symptom burden and health resource utilization. Other outcomes include patient survival, as well as interprofessional collaboration. We will also conduct prespecified subgroup analyses using variables such as PC needs, measured by the Needs of Social Nature, Existential Concerns, Symptoms, and Therapeutic Interaction scale. CONCLUSIONS: This trial will provide robust evidence about the impact of integrating SPC with critical care on patient, family, and health system outcomes.

Cyclophosphamide resets dendritic cell homeostasis and enhances antitumor immunity through effects that extend beyond regulatory T cell elimination.

Using a model of established malignancy, we found that cyclophosphamide (Cy), administered at a dose not requiring hematopoietic stem cell support, is superior to low-dose total body irradiation in augmenting antitumor immunity. We observed that Cy administration resulted in expansion of tumor antigen-specific T cells and transient depletion of CD4(+)Foxp3(+) regulatory T cells (Tregs). The antitumor efficacy of Cy was not improved by administration of anti-CD25 monoclonal antibody given to induce more profound Treg depletion. We found that Cy, through its myelosuppressive action, induced rebound myelopoiesis and perturbed dendritic cell (DC) homeostasis. The resulting DC turnover led to the emergence of tumor-infiltrating DCs that secreted more IL-12 and less IL-10 compared to those from untreated tumor-bearing animals. These newly recruited DCs, originating from proliferating early DC progenitors, were fully capable of priming T cell responses and ineffective in inducing expansion of Tregs. Together, our results show that Cy-mediated antitumor effects extend beyond the well-documented cytotoxicity and lymphodepletion and include resetting the DC homeostasis, thus providing an excellent platform for integration with other immunotherapeutic strategies.

Factors governing the activation of adoptively transferred donor T cells infused after allogeneic bone marrow transplantation in the mouse.

Murine models of bone marrow transplantation were used to study the mechanisms governing the activation of donor lymphocyte infusions (DLIs) manifesting as lymphohematopoietic graft-versus-host (LH-GVH) and graft-versus-leukemia (GVL) reactivities. We demonstrate here that established mixed chimerism influences the potency of DLI-mediated alloreactivity only in the MHC-mismatched but not MHC-matched setting. In the MHC-matched setting, high levels (>or= 40%) of residual host chimerism correlated negatively with DLI-mediated alloreactivity irrespective of the timing of their administration, the donor's previous sensitization to host antigens, or the level of residual host APCs. In vivo administration of Toll-like receptor (TLR) ligands was required to maximize DLI-mediated LH-GVH and GVL reactivities in chimeras with low levels (

Host-derived Langerhans cells persist after MHC-matched allografting independent of donor T cells and critically influence the alloresponses mediated by donor lymphocyte infusions.

Mouse models of minor histocompatibility Ag-mismatched bone marrow transplantation were used to study donor dendritic cell (DC) reconstitution after conditioning, variables influencing the persistence of residual host DCs in different compartments, their phenotype, and their role in governing donor lymphocyte infusion (DLI)-mediated alloresponses. Reconstitution of all splenic DC subsets occurred rapidly after bone marrow transplantation and before T cell reconstitution. However, in contrast to MHC-mismatched chimeras, residual host-derived DCs persisted in the cutaneous lymph nodes (CLNs) of MHC-matched chimeras despite the presence or addition of donor T cells to the graft. The phenotype of these residual host-derived DCs in CLNs was consistent with Langerhans' cells (LCs). We confirmed their skin origin and found near-complete preservation of host-derived LCs in the skin. Host-derived LCs retained their ability to continuously traffic to the CLNs, expressed homogeneously increased levels of costimulatory molecules, and could capture and carry epicutaneously applied Ags. To determine the role of residual host LCs in governing DLI-mediated alloresponses, we administered DLI alone or after topical application of the TLR7 ligand imiquimod, which is known to enhance the LC emigration from the skin. DLI administration resulted in a decrease in host-derived DCs in the CLNs and increased recruitment of donor-derived DCs to the skin, whereas imiquimod augmented their alloreactivity. These results suggest uniqueness of the MHC-matched setting in relation to the persistence of host-derived DCs in the skin and points to a previously unrecognized role of host-derived LCs in the induction of DLI-mediated graft-vs-host alloresponses.