Jeffery S Miller's scientific contributionswhile working at University of Minnesota Duluth, Duluth, Minnesota, United Statesand other institutions
- [Show abstract] ABSTRACT: B cell anti-host antibody production plays a central role in chronic graft-vs-host disease (cGVHD). T follicular helper (TFH) cells drive B cell responses and are implicated in this process. Given differences in cGVHD incidence between umbilical cord blood (UCB) and adult donor transplant recipients, we evaluated TFH cell reconstitution kinetics to define graft source differences and their potential pathogenic role in cGVHD. Although we observed significantly fewer TFH cells in the blood of UCB recipients (vs. matched related donors (MRD)) early after transplantation, by 1 year the numbers of TFH cells were similar. Additionally, at both early (day 60) and late (1 year) time points, TFH cell phenotype was predominantly central memory cells in both cohorts. TFH cells were functional and able to produce multiple cytokines (INF-γ, TNF-α, IL-2, IL-17 and IL-21) following stimulation. In contrast to mouse models where an enhanced frequency of splenic TFH cells contributes to cGVHD, patients with cGVHD showed significantly depleted circulating TFH cells following both UCB and MRD transplantation. Low numbers of TFH cells early after UCB transplantation could directly contribute to less cGVHD in this cohort. Additionally, systemic therapy (including steroids and calcineurin inhibitors) may contribute to decreases in TFH cells in patients with cGVHD. These data provide further evidence supporting the importance of TFH cells in cGVHD pathogenesis.
- [Show abstract] ABSTRACT: 1,25-Dihydroxyvitamin D3 [1,25(OH)2D3] is the biologically active form of vitamin D and is immunoregulatory. 1,25(OH)2D3 binds the vitamin D receptor complex present in many immune populations and can illicit transcriptional responses that vary among different immune subsets. The effects of 1,25(OH)2D3 on mature and developing human NK cells are not well characterized. In the present study, we examined the influence of 1,25(OH)2D3 using an established NK cell differentiation system. Briefly, umbilical cord blood CD34(+) cells were isolated and cultured in conditions optimal for NK cell differentiation, and varying concentrations of 1,25(OH)2D3 were administered. At physiological concentrations (10 nM), 1,25(OH)2D3 impaired NK cell development. Moreover, the NK cells that did develop under the influence of 1,25(OH)2D3 showed a significant reduction in function (cytotoxicity and cytokine production). Conversely, 1,25(OH)2D3 strongly induced hematopoietic stem cells to differentiate along a myeloid pathway, giving rise to CD14(+) cells. Mechanistically, 1,25(OH)2D3 drives hematopoietic progenitor cells to rapidly upregulate monocyte genes (i.e., C/EBP-α and CD14). There were no effects of 1,25(OH)2D3 on mature NK cytotoxicity or cytokine production. Collectively, these studies provide novel data showing the negative regulatory effect of 1,25(OH)2D3 on NK cell development.
- [Show abstract] ABSTRACT: Early after umbilical cord blood transplantation, patients show marked differences in bone marrow (BM) hematogone percentages. Little is known about whether these differences are clinically relevant. We hypothesized that early recovery of hematogones may be associated with improved transplantation outcomes. BM aspirates were assessed from 88 patients with acute myeloid leukemia by two independent reviewers at day 21 and 100 after umbilical cord blood transplantation. Interobserver variability for BM hematogone percentages at these time points showed correlation coefficients of 0.83 and 0.98, respectively (P ≤ .01 for both). A high percentage of hematogones at day 21 was associated with less acute graft-versus-host disease grade 3 to 4 (P = .01). At day 100, a high percentage of BM hematogones was associated with improved overall survival (P = .02) and lower treatment-related mortality (P ≤ .01). This study shows that BM hematogone percentages may be useful prognostic indicators in patients with acute myeloid leukemia after umbilical cord blood transplantation and should be routinely reported in BM differential counts.
- [Show abstract] ABSTRACT: Human secondary lymphoid tissues (SLTs) contain interleukin-22 (IL-22)-producing cells with an immature NK phenotype. Given their location, these cells are difficult to study. We have generated large numbers of NK22 cells from hematopoietic stem cells. HSC-derived NK22 cells show a CD56(+)CD117(high)CD94(-) phenotype, consistent with stage III NK progenitors. Like freshly isolated SLT stage III cells, HSC-derived NK22 cells express NKp44, CD161, CCR6, IL1 receptor, AHR, and ROR-γτ. IL-1β and IL-23 stimulation results in significant IL-22 but not interferon-γ production. Supernatant from these cells increases CD54 expression on mesenchymal stem cells. Thus, IL-22-producing NK cells can be generated in the absence of SLT. HSC-derived NK22 cells will be valuable in understanding this rare NK subset and create the opportunity for human translational clinical trials.
- [Show abstract] ABSTRACT: Hematopoietic stem cells (HSCs) by definition can differentiate into all types of blood cells.The development of multipotent hematopoietic cells into NK cells is a complex process. It is guided by environmental cues and intrinsic responsiveness of precursor cells to external signals. As hematopoietic progenitors progress in differentiation towards NK lineage, two concomitant processes occur: acquisition of NK specific gene expression pattern and gradual loss of the ability to express genes characteristic for other lineages. Transcription factors play a critical role in guiding lineage determination. There are several factors and events that promote HSC differentiation into the natural killer (NK) cell lineage. These include soluble factors, with a prominent role for interleukin 15, as well as contact- or gradient-dependent signals, such as Gas6/Tyro family of ligands and factors activating Wnt pathway. A complete understanding of the factors that control NK cell differentiation may allow for manipulation of NK cell reconstitution following hematopoietic cell transplantation and efficient ex vivo generation of NK cells for adoptive immune therapy. Interactions of hematopoietic progenitors with the environment provides growth factors and morphogenic signals that affect lineage fate and guide functional maturation via the triggering of inhibitory and/or activating receptors. The progression from multipotent hematopoietic precursors to mature NK cells can be described on the basis of stages of NK cell development. The development of any hematopoietic lineage can follow heterogenous pathways that lead to a common final point—a mature cell. As precursors traverse an individual developmental pathway, they are exposed to distinct sets of transcription factors, differing in magnitude and time of exposure.
- [Show abstract] ABSTRACT: Natural killer (NK) cells can alter the outcome of hematopoietic cell transplantation (HCT) if donor alloreactivity targets the recipient. Since most NK cells express inhibitory killer-immunoglobulin receptors (KIRs), we hypothesized that the susceptibility of recipient cells to donor NK cell-mediated lysis is genetically predetermined by the absence of known KIR ligands. We analyzed data from 2062 patients undergoing unrelated donor HCT for acute myeloid leukemia (AML; n = 556), chronic myeloid leukemia (CML; n = 1224), and myelodysplastic syndrome (MDS; n = 282). Missing 1 or more KIR ligands versus the presence of all ligands protected against relapse in patients with early myeloid leukemia (relative risk [RR] = 0.54; n = 536, 95% confidence interval [CI] 0.30-0.95, P = .03). In the subset of CML patients that received a transplant beyond 1 year from diagnosis (n = 479), missing a KIR ligand independently predicted a greater risk of developing grade 3-4 acute graft-versus-host disease (GVHD; RR = 1.58, 95% CI 1.13-2.22; P = .008). These data support a genetically determined role for NK cells following unrelated HCT in myeloid leukemia.
University of Minnesota DuluthDuluth, Minnesota, United States
Indiana University-Purdue University Indianapolis
Indianapolis, Indiana, United States
- Division of Hematology/Oncology