Selected Grantee Publications
Single-Cell Transcriptomics Predict Novel Potential Regulators of Acute Epithelial Restitution in the Ischemia-Injured Intestine
Rose et al., American Journal of Physiology-Gastrointestinal and Liver Physiology. 2025.
https://pubmed.ncbi.nlm.nih.gov/39853303
Following ischemia in the small intestine, early barrier restoration relies on epithelial restitution to reseal the physical barrier and prevent sepsis. Pigs share a similar gastrointestinal anatomy, physiology, and microbiota with humans. Researchers used neonatal and juvenile, 2- to 6-week-old male and female Yorkshire cross pigs to determine upstream regulators of restitution. Single-cell sequencing of ischemia-injured epithelial cells demonstrated two sub-phenotypes of absorptive enterocytes, with one subset presenting a restitution phenotype. Colony-stimulating factor-1 (CSF1) was the only predicted upstream regulator expressed in juvenile jejunum compared with neonatal jejunum. An in vitro scratch wound assay using IPEC-J2 cells showed that BLZ945, a colony-stimulating factor 1 receptor antagonist, inhibited restitution. Ex vivo ischemia-injured neonatal pig jejunum treated with exogenous CSF1 displayed increased barrier function. This study could inform future research focused on developing novel therapeutics for intestinal barrier injury in patients. Supported by ORIP (T32OD011130, K01OD028207), NCATS, NICHD, and NIDDK.
Large Animal Models Enhance the Study of Crypt-Mediated Epithelial Recovery From Prolonged Intestinal Ischemia Reperfusion Injury
McKinney-Aguirre et al., American Journal of Physiology-Gastrointestinal and Liver Physiology. 2024.
https://pubmed.ncbi.nlm.nih.gov/39404771/
Intestinal ischemia and reperfusion injury (IRI) is a severe pathological alteration that compromises the intestinal epithelial barrier, causing bacterial translocation, shock, sepsis, and potentially death. Preclinical research for IRI has focused on utilizing murine models, but mice demonstrate key anatomical and physiological intestinal differences from humans, such as tissue enzymes, intestinal permeability, and hypoxic response pathways. The researchers compared a 3-hour IRI porcine model to a 3-hour IRI murine model to reveal which demonstrated a stronger translational capacity. Both models demonstrated crypt damage, but only the porcine model showed recovery-associated crypt death expansion and re-epithelialization. At 72 hours post-IRI, mouse mortality was 84.6%, whereas porcine mortality was 0%. A porcine model would be more reliable for future translational studies focused on understanding IRI mechanisms for diagnosis and therapy advancements. Supported by ORIP (T32OD011130, K01OD010199, R03OD026598) and NIDDK.
Potent HPIV3-Neutralizing IGHV5-51 Antibodies Identified from Multiple Individuals Show L Chain and CDRH3 Promiscuity
Abu-Shmais et al., Journal of Immunology. 2024.
https://pubmed.ncbi.nlm.nih.gov/38488511/
Human parainfluenza virus 3 fusion glycoprotein (HPIV3 F), responsible for facilitating viral entry into host cells, is a major target of neutralizing antibodies that inhibit infection. More work is needed to understand these dynamics. Researchers characterized the genetic signatures, epitope specificity, neutralization potential, and publicness of HPIV3-specific antibodies identified across multiple individuals. From this work, they identified 12 potently neutralizing antibodies targeting three nonoverlapping epitopes on HPIV3 F. Six of the antibodies used immunoglobulin heavy variable gene, IGHV 5-51. These antibodies used different L chain variable genes (VL) and diverse H chain CDR 3 (CDRH3) sequences. These findings help elucidate the genetic and functional characteristics of HPIV3-neutralizing antibodies and indicate the existence of a reproducible H chain variable–dependent antibody response associated with VL and CDRH3 promiscuity. Supported by ORIP (K01OD036063), NCATS, NCI, NEI, NIAID, and NIDDK.
HIV-1 Remission: Accelerating the Path to Permanent HIV-1 Silencing
Lyons et al., c. 2023.
https://www.ncbi.nlm.nih.gov/pmc/articles/PMC10674359/
Current HIV treatment strategies are focused on forced proviral reactivation and elimination of reactivated cells with immunological or toxin-based technologies. Researchers have proposed the use of a novel “block-lock-stop” approach, which entails the long-term durable silencing of viral expression and permanent transcriptional deactivation of the latent provirus. In the present study, the authors present this approach and its rationale. More research is needed to understand the (1) epigenetic architecture of integrated provirus, (2) cell types and epigenetic cell states that favor viral rebound, (3) molecular functions of Tat (a protein that controls transcription of HIV) and host factors that prevent permanent silencing, (4) human endogenous retrovirus silencing in the genome, and (5) approaches to generate defective proviruses. Additionally, community engagement is crucial for this effort. Supported by ORIP (K01OD031900), NIAID, NCI, NIDA, NIDDK, NHLBI, NIMH, and NINDS.
Identification of an Anergic BND Cell–Derived Activated B Cell Population (BND2) in Young-Onset Type 1 Diabetes Patients
Stensland et al., The Journal of Experimental Medicine. 2023.
https://pubmed.ncbi.nlm.nih.gov/37184563/
B cells have been shown to play a role in the pathogenesis of type 1 diabetes (T1D), but the specificity, phenotype, and function of B cells in young-onset T1D is not understood fully. The investigators performed a cross-sectional analysis comparing insulin-reactive to tetanus-reactive B cells in the blood of male and female T1D patients and control participants using mass cytometry. They found elevated insulin-reactive BND2 cells in the blood and pancreatic lymph nodes of young-onset T1D donors. This work suggests that an antigen-specific B cell subset could contribute to the rapid progression of young-onset T1D. Supported by ORIP (K01OD028759) 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.
Orthotopic Transplantation of the Full-Length Porcine Intestine After Normothermic Machine Perfusion
Abraham et al., Transplantation Direct. 2022.
https://www.doi.org/10.1097/TXD.0000000000001390
Successful intestinal transplantation currently is hindered by graft injury that occurs during procurement and storage, which contributes to postoperative sepsis and allograft rejection. Improved graft preservation could expand transplantable graft numbers and enhance post-transplant outcomes. Superior transplant outcomes recently have been demonstrated in clinical trials using machine perfusion to preserve the liver. The investigators report the development and optimization of machine perfusion preservation of small intestine and successful transplantation of intestinal allografts in a porcine model. Supported by ORIP (K01OD019911), NIAID, and NIDDK.