Selected Grantee Publications
A Germ-Free Humanized Mouse Model Shows the Contribution of Resident Microbiota to Human-Specific Pathogen Infection
Wahl et al., Nature Biotechnology. 2023.
https://www.nature.com/articles/s41587-023-01906-5
Germ-free (GF) mice are of limited value in the study of human-specific pathogens because they do not support their replication. In this report, investigators developed a GF humanized mouse model using the bone marrow–liver–thymus platform to provide a robust and flexible in vivo model that can be used to study the role of resident microbiota in human health and disease. They demonstrated that resident microbiota promote viral acquisition and pathogenesis by using two human-specific pathogens, Epstein–Barr virus and HIV. Supported by ORIP (P40OD010995), FIC, NIAID, NCI, and NIDDK.
SALL1 Enforces Microglia-Specific DNA Binding and Function of SMADs to Establish Microglia Identity
Fixsen et al., Nature Immunology. 2023.
https://doi.org/10.1038/s41590-023-01528-8
Microglia function is thought to play a role in neurodevelopmental, psychiatric, and neurodegenerative diseases. Using knockout mice, investigators explored functional interactions between spalt-like transcription factor 1 (SALL1) and SMAD4, which demonstrated that interactions are mediated by a conserved microglia-specific SALL1 super-enhancer and result in direct activation of regulatory elements. The concerted interactions induce a microglia lineage determining program of gene expression. These findings indicate that expression of SALL1 and associated genes could contribute to phenotypes of aging and neurodegenerative diseases. Supported by ORIP (S10OD026929), NIA, NIMH, and NINDS.
Phytochemical Compound PB125 Attenuates Skeletal Muscle Mitochondrial Dysfunction and Impaired Proteostasis in a Model of Musculoskeletal Decline
Musci et al., Journal of Physiology. 2023.
https://physoc.onlinelibrary.wiley.com/doi/10.1113/JP282273
Age-related musculoskeletal decline contributes to disability and cardiometabolic diseases and is linked to impaired mitochondrial function and disrupted proteostasis. Using male and female Hartley guinea pigs, investigators tested a purported phytochemical activator of nuclear factor erythroid 2-related factor 2, which helps promote redox homeostasis, proteome maintenance, and mitochondrial energetics. They reported that the activator, PB125, improved mitochondrial respiration and attenuated disease- and age-related declines in skeletal muscle protein synthesis. This study provides insights for the development of interventions in humans. Supported by ORIP (T32OD010437) and NIA.
p38MAPKα Stromal Reprogramming Sensitizes Metastatic Breast Cancer to Immunotherapy
Faget et al., Cancer Discovery. 2023.
https://www.ncbi.nlm.nih.gov/pmc/articles/PMC10238649/
This study emphasizes the importance of the metastatic tumor microenvironment in metastatic breast cancer growth and the identification of effective antimetastatic therapies. Using a stromal labeling approach and single-cell RNA sequencing, the authors showed that a combination of p38MAPK inhibition (p38i) and anti-OX40 synergistically reduced metastatic tumor growth and increased overall survival. Further engagement of cytotoxic T cells cured all metastatic disease in mice and produced durable immunologic memory. The Cancer Genome Atlas data analysis revealed that patients with p38i metastatic stromal signature and a high tumor mutational burden (TMB) had increased overall survival. These findings suggest that patients with high TMB would benefit the most from the p38i plus anti-OX40 approach. Supported by ORIP (S10OD028483), NIA, NCI, and NIGMS.
Simultaneous Evaluation of Treatment Efficacy and Toxicity for Bispecific T-Cell Engager Therapeutics in a Humanized Mouse Model
Yang et al., The FASEB Journal. 2023.
https://faseb.onlinelibrary.wiley.com/doi/10.1096/fj.202300040R
Immuno-oncology–based therapies are an evolving powerful treatment strategy that targets the immune system and harnesses it to kill tumor cells directly. Investigators describe the novel application of a humanized mouse model that can simultaneously evaluate the efficacy of bispecific T cell engagers to control tumor burden and the development of cytokine release syndrome. The model also captures variability in responses for individual patients. Supported by ORIP (R24OD026440), NIAID, NCI, and NIDDK.
A LGR5 Reporter Pig Model Closely Resembles Human Intestine for Improved Study of Stem Cells in Disease
Schaaf et al., The FASEB Journal. 2023.
https://faseb.onlinelibrary.wiley.com/doi/10.1096/fj.202300223R
The constant epithelial regeneration in the intestine is the sole responsibility of intestinal epithelial stem cells (ISCs), which reside deep in the intestinal crypt structures. To effectively study ISCs, tools to identify this cell population are necessary. This study validates ISC isolation in a new porcine Leucine Rich Repeat Containing G Protein–Coupled Receptor 5 (LGR5) reporter line and demonstrates the use of these pigs as a novel colorectal cancer model. Overall, this novel porcine model provides critical advancement to the field of translational gastrointestinal research. Supported by ORIP (R21OD019738, K01OD019911), NCI, and NIDDK.
Lymph-Node-Based CD3+ CD20+ Cells Emerge From Membrane Exchange Between T Follicular Helper Cells and B Cells and Increase Their Frequency Following Simian Immunodeficiency Virus Infection
Samer et al., Journal of Virology. 2023.
https://www.doi.org/10.1128/jvi.01760-22
CD4+ T follicular helper cells are known to persist during antiretroviral therapy (ART) and have been identified as key targets for viral replication and persistence. Researchers identified a lymphocyte population that expresses CD3 (i.e., T cell lineage marker) and CD20 (i.e., B cell lineage marker) on the cellular surface in lymphoid tissues from rhesus macaques of both sexes and humans of male and female sexes. In macaques, the cells increased following simian immunodeficiency virus infection, were reduced with ART, and increased in frequency after ART interruption. These cells represent a potential area for future therapeutic strategies. Supported by ORIP (P51OD011132, U42OD011023), NIAID, NCI, NIDDK, NIDA, NHLBI, and NINDS.
Giardia Hinders Growth by Disrupting Nutrient Metabolism Independent of Inflammatory Enteropathy
Giallourou et al., Nature Communications. 2023.
https://www.nature.com/articles/s41467-023-38363-2
Giardia lamblia is one of the most common intestinal pathogens among children in low- and middle-income countries. Investigators performed translational investigations using the Malnutrition and Enteric Diseases (MAL-ED) male and female cohort, as well as mice of both sexes, to identify mechanistic pathways that might explain Giardia-induced effects on early childhood growth. They identified signatures in the urinary metabolome of young children, suggesting that host growth restriction during infection is mediated by dysregulated amino acid metabolism. Supported by ORIP (P40OD010995), NIAID, and NIDDK.
Association of Age at Menopause and Hormone Therapy Use With Tau and β-Amyloid Positron Emission Tomography
Coughlan et al., JAMA Neurology. 2023.
https://pubmed.ncbi.nlm.nih.gov/37010830/
To understand the predominance (70%) of women among individuals with Alzheimer’s disease, the investigators studied regional tau and β-amyloid (Aβ) in relation to age at menopause and hormone therapy (HT) in postmenopausal women and age-matched men using positron emission tomography. The study demonstrated that females exhibited higher tau deposition compared with age-matched males, particularly in the setting of elevated Aβ; earlier age at menopause and late initiation of HT were associated with increased tau vulnerability. This study suggests female individuals with these conditions may be at higher risk of pathological burden. Supported by ORIP (S10OD025245), NIA, and NICHD.
CD8+ T Cells Promote HIV Latency by Remodeling CD4+ T Cell Metabolism to Enhance Their Survival, Quiescence, and Stemness
Mutascio et al., Immunity. 2023.
https://www.doi.org/10.1016/j.immuni.2023.03.010
An HIV reservoir persists following antiretroviral therapy, representing the main barrier to an HIV cure. Using a validated in vitro model, investigators explored the mechanism by which CD8+ T cells promote HIV latency and inhibit latency reversal in HIV-infected CD4+ T cells. They reported that CD8+ T cells favor the establishment of HIV latency by modulating metabolic, stemness, and survival pathways that correlate with the downregulation of HIV expression and promote HIV latency. In future studies, comparative analyses may provide insight into common molecular mechanisms in the silencing of HIV expression by CD8+ T cells and macrophages, which can be applied to new intervention strategies that target the HIV reservoir. Supported by ORIP (P51OD011132, S10OD026799), NIAID, NIDDK, NIDA, NHLBI, and NINDS.