Long-Term Safety and Efficacy of Gene-Pulmonary Macrophage Transplantation Therapy of PAP in Csf2ra−/− Mice

Abstract

Hereditary pulmonary alveolar proteinosis (PAP) is a genetic lung disease characterized by surfactant accumulation and respiratory failure arising from disruption of GM-CSF signaling. While mutations in either CSF2RA or CSF2RB (encoding GM-CSF receptor a or b chains, respectively) can cause PAP, a chain mutations are responsible in most patients. Pulmonary macrophage transplantation (PMT) is a promising new cell therapy in development; however, no studies have evaluated this approach for hereditary PAP (hPAP) caused by Csf2ra mutations. Here, we report on the preclinical safety, tolerability, and efficacy of lentiviral-vector (LV)-mediated Csf2ra expression in macrophages and PMT of gene-corrected macrophages (gene-PMT therapy) in Csf2ra gene-ablated (Csf2ra À/À) mice. Gene-PMT therapy resulted in a stable transgene integration and correction of GM-CSF signaling and functions in Csf2ra À/À macrophages in vitro and in vivo and resulted in engraftment and long-term persistence of gene-corrected macrophages in alveoli; restoration of pulmonary surfactant homeostasis; correction of PAP-specific cytologic, histologic, and biomarker abnormalities; and reduced inflammation associated with disease progression in untreated mice. No adverse consequences of gene-PMT therapy in Csf2ra À/À mice were observed. Results demonstrate that gene-PMT therapy of hPAP in Csf2ra À/À mice was highly efficacious, durable, safe, and well tolerated.

Integrative Identification of Hub Genes Associated With Immune Cells in Atrial Fibrillation Using Weighted Gene Correlation Network Analysis

“…The activating hotspot mutation in CSFR2B was identified in myeloid leukemia in Down syndrome ( 36 ). The mutation in CSF2RB can also cause hereditary pulmonary alveolar proteinosis (PAP) ( 37 ). In CSF2RB -/- mice, statin therapy reduces cholesterol accumulation in alveolar macrophages and ameliorates PAP ( 38 ).…”

Pulmonary Alveolar Proteinosis Syndrome

“…Pulmonary macrophage transplantation, a process whereby healthy-donor or gene-corrected bonemarrow-derived macrophages were delivered directly to the lungs of Csf2rb À/À and Csf2ra À/À mice, resulting in improved lung disease and reduced mortality. 115,116,119,120 The transplanted macrophages persisted for more than 1 year after transplantation and retained therapeutic efficacy throughout this period. Moreover, it is now possible to genetically correct macrophages from patient-derived induced pluripotent stemcells, 121,122 opening the possibility of translating this into clinical trials in humans with hereditary PAP.…”

Role of GM-CSF in regulating metabolism and mitochondrial functions critical to macrophage proliferation

“…Systemic overexpression of GM-CSF in mice results in marked accumulation of macrophages in tissues throughout the body and increased mortality (Lang et al, 1987). In contrast, disruption of GM-CSF signaling results in another lung disease, pulmonary alveolar proteinosis (PAP), characterized by functional impairment of AMs including reduced pulmonary surfactant clearance and numerous other functions (Arumugam et al, 2019; Suzuki et al, 2014; Suzuki et al, 2008; Suzuki et al, 2010; Trapnell and Whitsett, 2002; Willinger et al, 2011). Of note, the manifestations of this lung disease are similar regardless of whether disruption of GM-CSF signaling occurs by ablation of the gene encoding GM-CSF, its receptor alpha or beta subunits, or neutralizing GM-CSF autoantibodies (Arumugam et al, 2019; Berclaz et al, 2007; Dranoff et al, 1994; Shibata et al, 2001; Suzuki et al, 2014; Suzuki et al, 2011; Tanaka et al, 2011).…”

“…In contrast, disruption of GM-CSF signaling results in another lung disease, pulmonary alveolar proteinosis (PAP), characterized by functional impairment of AMs including reduced pulmonary surfactant clearance and numerous other functions (Arumugam et al, 2019; Suzuki et al, 2014; Suzuki et al, 2008; Suzuki et al, 2010; Trapnell and Whitsett, 2002; Willinger et al, 2011). Of note, the manifestations of this lung disease are similar regardless of whether disruption of GM-CSF signaling occurs by ablation of the gene encoding GM-CSF, its receptor alpha or beta subunits, or neutralizing GM-CSF autoantibodies (Arumugam et al, 2019; Berclaz et al, 2007; Dranoff et al, 1994; Shibata et al, 2001; Suzuki et al, 2014; Suzuki et al, 2011; Tanaka et al, 2011). Disruption of GM-CSF signaling in mice, monkeys, and man is associated with decreased expression of the master transcriptional regulator, PU.l, in all three species, as well as the downstream transcription factor, PPARγ that is required for the AM differentiation and specification (Berclaz et al, 2002b; Bonfield et al, 2003; Carey et al, 2007; Gonzalez-Juarrero et al, 2005; Sakagami et al, 2010; Sallese et al, 2017; Suzuki et al, 2014; Suzuki et al, 2011; Suzuki et al, 2008; Suzuki et al, 2010; Trapnell and Whitsett, 2002; Uchida et al, 2009; Uchida et al, 2004).…”

“…This model system has been extensively studied in a program to develop this approach – pulmonary macrophage transplantation (PMT) – as therapy of hereditary PAP caused by genetic mutations in CSF2RA or CSF2RB. A cornerstone of the treatment approach is that the transplanted macrophages self-renew, thereby contributing to the long-term persistence and durability of the treatment (Arumugam et al, 2019; Suzuki et al, 2014). These studies also identified a reciprocal feedback loop through which pulmonary GM-CSF has been demonstrated to regulate the size of the AM population in mice (Suzuki et al, 2014).…”